Binding and Translocation of Termination Factor Rho Studied at the Single-Molecule Level

Science.gov (United States)

Koslover, Daniel J.; Fazal, Furqan M.; Mooney, Rachel A.; Landick, Robert; Block, Steven M.

2012-01-01

Rho termination factor is an essential hexameric helicase responsible for terminating 20–50% of all mRNA synthesis in E. coli. We used single- molecule force spectroscopy to investigate Rho-RNA binding interactions at the Rho- utilization (rut) site of the ? tR1 terminator. Our results are consistent with Rho complexes adopting two states, one that binds 57 ±2 nucleotides of RNA across all six of the Rho primary binding sites, and another that binds 85 ±2 nucleotides at the six primary sites plus a single secondary site situated at the center of the hexamer. The single-molecule data serve to establish that Rho translocates 5′-to-3′ towards RNA polymerase (RNAP) by a tethered-tracking mechanism, looping out the intervening RNA between the rut site and RNAP. These findings lead to a general model for Rho binding and translocation, and establish a novel experimental approach that should facilitate additional single- molecule studies of RNA-binding proteins. PMID:22885804

A Salmonella typhimurium-translocated Glycerophospholipid:Cholesterol Acyltransferase Promotes Virulence by Binding to the RhoA Protein Switch Regions

Energy Technology Data Exchange (ETDEWEB)

LaRock, Doris L.; Brzovic, Peter S.; Levin, Itay; Blanc, Marie-Pierre; Miller, Samuel I.

2012-08-24

Salmonella enterica serovar typhimurium translocates a glycerophospholipid: cholesterol acyltransferase (SseJ) into the host cytosol after its entry into mammalian cells. SseJ is recruited to the cytoplasmic face of the host cell phagosome membrane where it is activated upon binding the small GTPase, RhoA. SseJ is regulated similarly to cognate eukaryotic effectors, as only the GTP-bound form of RhoA family members stimulates enzymatic activity. Using NMR and biochemistry, this work demonstrates that SseJ competes effectively with Rhotekin, ROCK, and PKN1 in binding to a similar RhoA surface. The RhoA surface that binds SseJ includes the regulatory switch regions that control activation of mammalian effectors. These data were used to create RhoA mutants with altered SseJ binding and activation. This structure-function analysis supports a model in which SseJ activation occurs predominantly through binding to residues within switch region II. We further defined the nature of the interaction between SseJ and RhoA by constructing SseJ mutants in the RhoA binding surface. These data indicate that SseJ binding to RhoA is required for recruitment of SseJ to the endosomal network and for full Salmonella virulence for inbred susceptible mice, indicating that regulation of SseJ by small GTPases is an important virulence strategy of this bacterial pathogen. The dependence of a bacterial effector on regulation by a mammalian GTPase defines further how intimately host pathogen interactions have coevolved through similar and divergent evolutionary strategies.

RHO Mutations (p.W126L and p.A346P in Two Japanese Families with Autosomal Dominant Retinitis Pigmentosa

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Satoshi Katagiri

2014-01-01

Full Text Available Purpose. To investigate genetic and clinical features of patients with rhodopsin (RHO mutations in two Japanese families with autosomal dominant retinitis pigmentosa (adRP. Methods. Whole-exome sequence analysis was performed in ten adRP families. Identified RHO mutations for the cosegregation analysis were confirmed by Sanger sequencing. Ophthalmic examinations were performed to evaluate the RP phenotypes. The impact of the RHO mutation on the rhodopsin conformation was examined by molecular modeling analysis. Results. In two adRP families, we identified two RHO mutations (c.377G>T (p.W126L and c.1036G>C (p.A346P, one of which was novel. Complete cosegregation was confirmed for each mutation exhibiting the RP phenotype in both families. Molecular modeling predicted that the novel mutation (p.W126L might impair rhodopsin function by affecting its conformational transition in the light-adapted form. Clinical phenotypes showed that patients with p.W126L exhibited sector RP, whereas patients with p.A346P exhibited classic RP. Conclusions. Our findings demonstrated that the novel mutation (p.W126L may be associated with the phenotype of sector RP. Identification of RHO mutations is a very useful tool for predicting disease severity and providing precise genetic counseling.

Rickettsia parkeri invasion of diverse host cells involves an Arp2/3 complex, WAVE complex and Rho-family GTPase-dependent pathway.

Science.gov (United States)

Reed, Shawna C O; Serio, Alisa W; Welch, Matthew D

2012-04-01

Rickettsiae are obligate intracellular pathogens that are transmitted to humans by arthropod vectors and cause diseases such as spotted fever and typhus. Although rickettsiae require the host cell actin cytoskeleton for invasion, the cytoskeletal proteins that mediate this process have not been completely described. To identify the host factors important during cell invasion by Rickettsia parkeri, a member of the spotted fever group (SFG), we performed an RNAi screen targeting 105 proteins in Drosophila melanogaster S2R+ cells. The screen identified 21 core proteins important for invasion, including the GTPases Rac1 and Rac2, the WAVE nucleation-promoting factor complex and the Arp2/3 complex. In mammalian cells, including endothelial cells, the natural targets of R. parkeri, the Arp2/3 complex was also crucial for invasion, while requirements for WAVE2 as well as Rho GTPases depended on the particular cell type. We propose that R. parkeri invades S2R+ arthropod cells through a primary pathway leading to actin nucleation, whereas invasion of mammalian endothelial cells occurs via redundant pathways that converge on the host Arp2/3 complex. Our results reveal a key role for the WAVE and Arp2/3 complexes, as well as a higher degree of variation than previously appreciated in actin nucleation pathways activated during Rickettsia invasion. © 2011 Blackwell Publishing Ltd.

Involvement of the actin cytoskeleton and p21rho-family GTPases in the pathogenesis of the human protozoan parasite Entamoeba histolytica

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G.D. Godbold

1998-08-01

Full Text Available It has been estimated that infection with the enteric protozoan parasite Entamoeba histolytica kills more than 50,000 people a year. Central to the pathogenesis of this organism is its ability to directly lyse host cells and cause tissue destruction. Amebic lesions show evidence of cell lysis, tissue necrosis, and damage to the extracellular matrix. The specific molecular mechanisms by which these events are initiated, transmitted, and effected are just beginning to be uncovered. In this article we review what is known about host cell adherence and contact-dependent cytolysis. We cover the involvement of the actin cytoskeleton and small GTP-binding proteins of the p21rho-family in the process of cell killing and phagocytosis, and also look at how amebic interactions with molecules of the extracellular matrix contribute to its cytopathic effects.

Identification of a negative regulatory region for the exchange activity and characterization of T332I mutant of Rho guanine nucleotide exchange factor 10 (ARHGEF10).

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Chaya, Taro; Shibata, Satoshi; Tokuhara, Yasunori; Yamaguchi, Wataru; Matsumoto, Hiroshi; Kawahara, Ichiro; Kogo, Mikihiko; Ohoka, Yoshiharu; Inagaki, Shinobu

2011-08-26

The T332I mutation in Rho guanine nucleotide exchange factor 10 (ARHGEF10) was previously found in persons with slowed nerve conduction velocities and thin myelination of peripheral nerves. However, the molecular and cellular basis of the T332I mutant is not understood. Here, we show that ARHGEF10 has a negative regulatory region in the N terminus, in which residue 332 is located, and the T332I mutant is constitutively active. An N-terminal truncated ARHGEF10 mutant, ARHGEF10 ΔN (lacking amino acids 1-332), induced cell contraction that was inhibited by a Rho kinase inhibitor Y27632 and had higher GEF activity for RhoA than the wild type. The T332I mutant also showed the phenotype similar to the N-terminal truncated mutant. These data suggest that the ARHGEF10 T332I mutation-associated phenotype observed in the peripheral nerves is due to activated GEF activity of the ARHGEF10 T332I mutant.

Identification of a Negative Regulatory Region for the Exchange Activity and Characterization of T332I Mutant of Rho Guanine Nucleotide Exchange Factor 10 (ARHGEF10)*

Science.gov (United States)

Chaya, Taro; Shibata, Satoshi; Tokuhara, Yasunori; Yamaguchi, Wataru; Matsumoto, Hiroshi; Kawahara, Ichiro; Kogo, Mikihiko; Ohoka, Yoshiharu; Inagaki, Shinobu

2011-01-01

The T332I mutation in Rho guanine nucleotide exchange factor 10 (ARHGEF10) was previously found in persons with slowed nerve conduction velocities and thin myelination of peripheral nerves. However, the molecular and cellular basis of the T332I mutant is not understood. Here, we show that ARHGEF10 has a negative regulatory region in the N terminus, in which residue 332 is located, and the T332I mutant is constitutively active. An N-terminal truncated ARHGEF10 mutant, ARHGEF10 ΔN (lacking amino acids 1–332), induced cell contraction that was inhibited by a Rho kinase inhibitor Y27632 and had higher GEF activity for RhoA than the wild type. The T332I mutant also showed the phenotype similar to the N-terminal truncated mutant. These data suggest that the ARHGEF10 T332I mutation-associated phenotype observed in the peripheral nerves is due to activated GEF activity of the ARHGEF10 T332I mutant. PMID:21719701

Signaling efficiency of Gαq through its effectors p63RhoGEF and GEFT depends on their subcellular location.

Science.gov (United States)

Goedhart, Joachim; van Unen, Jakobus; Adjobo-Hermans, Merel J W; Gadella, Theodorus W J

2013-01-01

The p63RhoGEF and GEFT proteins are encoded by the same gene and both members of the Dbl family of guanine nucleotide exchange factors. These proteins can be activated by the heterotrimeric G-protein subunit Gαq. We show that p63RhoGEF is located at the plasma membrane, whereas GEFT is confined to the cytoplasm. Live-cell imaging studies yielded quantitative information on diffusion coefficients, association rates and encounter times of GEFT and p63RhoGEF. Calcium signaling was examined as a measure of the signal transmission, revealing more efficient signaling through the membrane-associated p63RhoGEF. A rapamycin dependent recruitment system was used to dynamically alter the subcellular location and concentration of GEFT, showing efficient signaling through GEFT only upon membrane recruitment. Together, our results show efficient signal transmission through membrane located effectors, and highlight a role for increased concentration rather than increased encounter times due to membrane localization in the Gαq mediated pathways to p63RhoGEF and PLCβ.

Solo, a RhoA-targeting guanine nucleotide exchange factor, is critical for hemidesmosome formation and acinar development in epithelial cells.

Science.gov (United States)

Fujiwara, Sachiko; Matsui, Tsubasa S; Ohashi, Kazumasa; Deguchi, Shinji; Mizuno, Kensaku

2018-01-01

Cell-substrate adhesions are essential for various physiological processes, including embryonic development and maintenance of organ functions. Hemidesmosomes (HDs) are multiprotein complexes that attach epithelial cells to the basement membrane. Formation and remodeling of HDs are dependent on the surrounding mechanical environment; however, the upstream signaling mechanisms are not well understood. We recently reported that Solo (also known as ARHGEF40), a guanine nucleotide exchange factor targeting RhoA, binds to keratin8/18 (K8/K18) intermediate filaments, and that their interaction is important for force-induced actin and keratin cytoskeletal reorganization. In this study, we show that Solo co-precipitates with an HD protein, β4-integrin. Co-precipitation assays revealed that the central region (amino acids 330-1057) of Solo binds to the C-terminal region (1451-1752) of β4-integrin. Knockdown of Solo significantly suppressed HD formation in MCF10A mammary epithelial cells. Similarly, knockdown of K18 or treatment with Y-27632, a specific inhibitor of Rho-associated kinase (ROCK), suppressed HD formation. As Solo knockdown or Y-27632 treatment is known to disorganize K8/K18 filaments, these results suggest that Solo is involved in HD formation by regulating K8/K18 filament organization via the RhoA-ROCK signaling pathway. We also showed that knockdown of Solo impairs acinar formation in MCF10A cells cultured in 3D Matrigel. In addition, Solo accumulated at the site of traction force generation in 2D-cultured MCF10A cells. Taken together, these results suggest that Solo plays a crucial role in HD formation and acinar development in epithelial cells by regulating mechanical force-induced RhoA activation and keratin filament organization.

A Steric-inhibition model for regulation of nucleotide exchange via the Dock180 family of GEFs.

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Lu, Mingjian; Kinchen, Jason M; Rossman, Kent L; Grimsley, Cynthia; Hall, Matthew; Sondek, John; Hengartner, Michael O; Yajnik, Vijay; Ravichandran, Kodi S

2005-02-22

CDM (CED-5, Dock180, Myoblast city) family members have been recently identified as novel, evolutionarily conserved guanine nucleotide exchange factors (GEFs) for Rho-family GTPases . They regulate multiple processes, including embryonic development, cell migration, apoptotic-cell engulfment, tumor invasion, and HIV-1 infection, in diverse model systems . However, the mechanism(s) of regulation of CDM proteins has not been well understood. Here, our studies on the prototype member Dock180 reveal a steric-inhibition model for regulating the Dock180 family of GEFs. At basal state, the N-terminal SH3 domain of Dock180 binds to the distant catalytic Docker domain and negatively regulates the function of Dock180. Further studies revealed that the SH3:Docker interaction sterically blocks Rac access to the Docker domain. Interestingly, ELMO binding to the SH3 domain of Dock180 disrupted the SH3:Docker interaction, facilitated Rac access to the Docker domain, and contributed to the GEF activity of the Dock180/ELMO complex. Additional genetic rescue studies in C. elegans suggested that the regulation of the Docker-domain-mediated GEF activity by the SH3 domain and its adjoining region is evolutionarily conserved. This steric-inhibition model may be a general mechanism for regulating multiple SH3-domain-containing Dock180 family members and may have implications for a variety of biological processes.

An extracellular-matrix-specific GEF-GAP interaction regulates Rho GTPase crosstalk for 3D collagen migration.

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Kutys, Matthew L; Yamada, Kenneth M

2014-09-01

Rho-family GTPases govern distinct types of cell migration on different extracellular matrix proteins in tissue culture or three-dimensional (3D) matrices. We searched for mechanisms selectively regulating 3D cell migration in different matrix environments and discovered a form of Cdc42-RhoA crosstalk governing cell migration through a specific pair of GTPase activator and inhibitor molecules. We first identified βPix, a guanine nucleotide exchange factor (GEF), as a specific regulator of migration in 3D collagen using an affinity-precipitation-based GEF screen. Knockdown of βPix specifically blocks cell migration in fibrillar collagen microenvironments, leading to hyperactive cellular protrusion accompanied by increased collagen matrix contraction. Live FRET imaging and RNAi knockdown linked this βPix knockdown phenotype to loss of polarized Cdc42 but not Rac1 activity, accompanied by enhanced, de-localized RhoA activity. Mechanistically, collagen phospho-regulates βPix, leading to its association with srGAP1, a GTPase-activating protein (GAP), needed to suppress RhoA activity. Our results reveal a matrix-specific pathway controlling migration involving a GEF-GAP interaction of βPix with srGAP1 that is critical for maintaining suppressive crosstalk between Cdc42 and RhoA during 3D collagen migration.

Rac1 and RhoA: Networks, loops and bistability.

Science.gov (United States)

Nguyen, Lan K; Kholodenko, Boris N; von Kriegsheim, Alex

2016-08-17

Cell migration requires a precise temporal and spatial coordination of several processes which allow the cell to efficiently move. The extension and retraction of membrane protrusion, as well as adhesion are controlled by the Rho-family small GTPases. Two members of the family, Rac1 and RhoA, can show opposite behaviors and spatial localisations, with RhoA being active toward the rear of the cell and regulating its retraction during migration, whereas Rac1 is active toward the front of the cell. In addition to the spatial segregation, RhoA and Rac1 activity at the leading edge of the cells has an element of temporal segregation, with RhoA and Rac1 activities peaking at separate points during the migratory cycle of protrusion and retraction. Elements of this separation have been explained by the presence of 2 mutually inhibitory feedbacks, where Rac1 inhibits RhoA and RhoA in turn can inhibit Rac1. Recently, it was shown that Rac1 and RhoA activity and downstream signaling respond in a bistable manner to perturbations of this network.

Differential binding of RhoA, RhoB, and RhoC to protein kinase C-related kinase (PRK) isoforms PRK1, PRK2, and PRK3: PRKs have the highest affinity for RhoB.

Science.gov (United States)

Hutchinson, Catherine L; Lowe, Peter N; McLaughlin, Stephen H; Mott, Helen R; Owen, Darerca

2013-11-12

Protein kinase C-related kinases (PRKs) are members of the protein kinase C superfamily of serine-threonine kinases and can be activated by binding to members of the Rho family of GTPases via a Rho-binding motif known as an HR1 domain. Three tandem HR1 domains reside at the N-terminus of the PRKs. We have assessed the ability of the HR1a and HR1b domains from the three PRK isoforms (PRK1, PRK2, and PRK3) to interact with the three Rho isoforms (RhoA, RhoB, and RhoC). The affinities of RhoA and RhoC for a construct encompassing both PRK1 HR1 domains were similar to those for the HR1a domain alone, suggesting that these interactions are mediated solely by the HR1a domain. The affinities of RhoB for both the PRK1 HR1a domain and the HR1ab didomain were higher than those of RhoA or RhoC. RhoB also bound more tightly to the didomain than to the HR1a domain alone, implicating the HR1b domain in the interaction. As compared with PRK1 HR1 domains, PRK2 and PRK3 domains bind less well to all Rho isoforms. Uniquely, however, the PRK3 domains display a specificity for RhoB that requires both the C-terminus of RhoB and the PRK3 HR1b domain. The thermal stability of the HR1a and HR1b domains was also investigated. The PRK2 HR1a domain was found to be the most thermally stable, while PRK2 HR1b, PRK3 HR1a, and PRK3 HR1b domains all exhibited lower melting temperatures, similar to that of the PRK1 HR1a domain. The lower thermal stability of the PRK2 and PRK3 HR1b domains may impart greater flexibility, driving their ability to interact with Rho isoforms.

The atypical Rho GTPase RhoD is a regulator of actin cytoskeleton dynamics and directed cell migration

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Blom, Magdalena; Reis, Katarina [Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm (Sweden); Heldin, Johan [Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala SE-751 22 Uppsala (Sweden); Kreuger, Johan [Department of Medical Cell Biology, Science for Life Laboratory, Uppsala University, SE-751 23 Uppsala (Sweden); Aspenström, Pontus, E-mail: pontus.aspenstrom@ki.se [Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm (Sweden)

2017-03-15

RhoD belongs to the Rho GTPases, a protein family responsible for the regulation and organization of the actin cytoskeleton, and, consequently, many cellular processes like cell migration, cell division and vesicle trafficking. Here, we demonstrate that the actin cytoskeleton is dynamically regulated by increased or decreased protein levels of RhoD. Ectopic expression of RhoD has previously been shown to give an intertwined weave of actin filaments. We show that this RhoD-dependent effect is detected in several cell types and results in a less dynamic actin filament system. In contrast, RhoD depletion leads to increased actin filament-containing structures, such as cortical actin, stress fibers and edge ruffles. Moreover, vital cellular functions such as cell migration and proliferation are defective when RhoD is silenced. Taken together, we present data suggesting that RhoD is an important component in the control of actin dynamics and directed cell migration. - Highlights: • Increased RhoD expression leads to loss of actin structures, e.g. stress fibers and gives rise to decreased actin dynamics. • RhoD knockdown induces various actin-containing structures such as edge ruffles, stress fibers and cortical actin, in a cell-type specific manner. • RhoD induces specific actin rearrangements depending on its subcellular localization. • RhoD knockdown has effects on cellular processes, such as directed cell migration and proliferation.

The atypical Rho GTPase RhoD is a regulator of actin cytoskeleton dynamics and directed cell migration

International Nuclear Information System (INIS)

Blom, Magdalena; Reis, Katarina; Heldin, Johan; Kreuger, Johan; Aspenström, Pontus

2017-01-01

RhoD belongs to the Rho GTPases, a protein family responsible for the regulation and organization of the actin cytoskeleton, and, consequently, many cellular processes like cell migration, cell division and vesicle trafficking. Here, we demonstrate that the actin cytoskeleton is dynamically regulated by increased or decreased protein levels of RhoD. Ectopic expression of RhoD has previously been shown to give an intertwined weave of actin filaments. We show that this RhoD-dependent effect is detected in several cell types and results in a less dynamic actin filament system. In contrast, RhoD depletion leads to increased actin filament-containing structures, such as cortical actin, stress fibers and edge ruffles. Moreover, vital cellular functions such as cell migration and proliferation are defective when RhoD is silenced. Taken together, we present data suggesting that RhoD is an important component in the control of actin dynamics and directed cell migration. - Highlights: • Increased RhoD expression leads to loss of actin structures, e.g. stress fibers and gives rise to decreased actin dynamics. • RhoD knockdown induces various actin-containing structures such as edge ruffles, stress fibers and cortical actin, in a cell-type specific manner. • RhoD induces specific actin rearrangements depending on its subcellular localization. • RhoD knockdown has effects on cellular processes, such as directed cell migration and proliferation.

Guanine nucleotide exchange factor αPIX leads to activation of the Rac 1 GTPase/glycogen phosphorylase pathway in interleukin (IL)-2-stimulated T cells

DEFF Research Database (Denmark)

Llavero, Francisco; Urzelai, Bakarne; Osinalde, Nerea

2015-01-01

Recently, we have reported that the active form of Rac 1 GTPase binds to the glycogen phosphorylase muscle isoform (PYGM) and modulates its enzymatic activity leading to T cell proliferation. In the lymphoid system, Rac 1 and in general other small GTPases of the Rho family participate...... in the signaling cascades that are activated after engagement of the T cell antigen receptor. However, little is known about the IL-2-dependent Rac 1 activator molecules. For the first time, a signaling pathway leading to the activation of Rac 1/PYGM in response to IL-2-stimulated T cell proliferation is described....... More specifically, αPIX, a known guanine nucleotide exchange factor for the small GTPases of the Rho family, preferentially Rac 1, mediates PYGM activation in Kit 225 T cells stimulated with IL-2. Using directed mutagenesis, phosphorylation of αPIX Rho-GEF serines 225 and 488 is required for activation...

Gα12/13 signaling promotes cervical cancer invasion through the RhoA/ROCK-JNK signaling axis

International Nuclear Information System (INIS)

Yuan, Bo; Cui, Jinquan; Wang, Wuliang; Deng, Kehong

2016-01-01

Several reports have indicated a role for the members of the G12 family of heterotrimeric G proteins (Gα12 and Gα13) in oncogenesis and tumor cell growth. The aims of the present study were to evaluate the role of G12 signaling in cervical cancer. We demonstrated that expression of the G12 proteins was highly upregulated in cervical cancer cells. Additionally, expression of the activated forms of Gα12/Gα13 but not expression of activated Gαq induced cell invasion through the activation of the RhoA family of G proteins, but had no effect on cell proliferation in the cervical cancer cells. Inhibition of G12 signaling by expression of the RGS domain of the p115-Rho-specific guanine nucleotide exchange factor (p115-RGS) blocked thrombin-stimulated cell invasion, but did not inhibit cell proliferation in cervical cells, whereas the inhibition of Gαq (RGS2) had no effect. Furthermore, G12 signaling was able to activate Rho proteins, and this stimulation was inhibited by p115-RGS, and Gα12-induced invasion was blocked by an inhibitor of RhoA/B/C (C3 toxin). Pharmacological inhibition of JNK remarkably decreased G12-induced JNK activation. Both a JNK inhibitor (SP600125) and a ROCK inhibitor (Y27632) reduced G12-induced JNK and c-Jun activation, and markedly inhibited G12-induced cellular invasion. Collectively, these findings demonstrate that stimulation of G12 proteins is capable of promoting invasion through RhoA/ROCK-JNK activation. -- Highlights: •Gα12/Gα13 is upregulated in cervical cancer cell lines. •Gα12/Gα13 is not involved in cervical cancer cell proliferation. •Gα12/Gα13 promotes cervical cancer cell invasion. •The role of Rho G proteins in G12-promoted cervical cancer cell invasion. •G12 promotes cell invasion through activation of the ROCK-JNK signaling axis.

RhoG regulates anoikis through a phosphatidylinositol 3-kinase-dependent mechanism

International Nuclear Information System (INIS)

Yamaki, Nao; Negishi, Manabu; Katoh, Hironori

2007-01-01

In normal epithelial cells, cell-matrix interaction is required for cell survival and proliferation, whereas disruption of this interaction causes epithelial cells to undergo apoptosis called anoikis. Here we show that the small GTPase RhoG plays an important role in the regulation of anoikis. HeLa cells are capable of anchorage-independent cell growth and acquire resistance to anoikis. We found that RNA interference-mediated knockdown of RhoG promoted anoikis in HeLa cells. Previous studies have shown that RhoG activates Rac1 and induces several cellular functions including promotion of cell migration through its effector ELMO and the ELMO-binding protein Dock180 that function as a Rac-specific guanine nucleotide exchange factor. However, RhoG-induced suppression of anoikis was independent of the ELMO- and Dock180-mediated activation of Rac1. On the other hand, the regulation of anoikis by RhoG required phosphatidylinositol 3-kinase (PI3K) activity, and constitutively active RhoG bound to the PI3K regulatory subunit p85α and induced the PI3K-dependent phosphorylation of Akt. Taken together, these results suggest that RhoG protects cells from apoptosis caused by the loss of anchorage through a PI3K-dependent mechanism, independent of its activation of Rac1

Molecular characterization of a novel RhoGAP, RRC-1 of the nematode Caenorhabditis elegans

International Nuclear Information System (INIS)

Delawary, Mina; Nakazawa, Takanobu; Tezuka, Tohru; Sawa, Mariko; Iino, Yuichi; Takenawa, Tadaomi; Yamamoto, Tadashi

2007-01-01

The GTPase-activating proteins for Rho family GTPases (RhoGAP) transduce diverse intracellular signals by negatively regulating Rho family GTPase-mediated pathways. In this study, we have cloned and characterized a novel RhoGAP for Rac1 and Cdc42, termed RRC-1, from Caenorhabditis elegans. RRC-1 was highly homologous to mammalian p250GAP and promoted GTP hydrolysis of Rac1 and Cdc42 in cells. The rrc-1 mRNA was expressed in all life stages. Using an RRC-1::GFP fusion protein, we found that RRC-1 was localized to the coelomocytes, excretory cell, GLR cells, and uterine-seam cell in adult worms. These data contribute toward understanding the roles of Rho family GTPases in C. elegans

TrkB-T1 regulates the RhoA signaling and actin cytoskeleton in glioma cells

International Nuclear Information System (INIS)

Ohira, Koji; Homma, Koichi J.; Hirai, Hirohisa; Nakamura, Shun; Hayashi, Motoharu

2006-01-01

Recently, the truncated TrkB receptor, T1, has been reported to be involved in the control of cell morphology via the regulation of Rho proteins, through which T1 binds Rho guanine nucleotide dissociation inhibitor (Rho GDI) 1 and dissociates it in a brain-derived neurotrophic factor (BDNF)-dependent manner. However, it is unclear whether T1 signaling regulates the downstream of Rho signaling and the actin cytoskeleton. In this study, we investigated this question using C6 rat glioma cells, which express T1 endogenously. Rho GDI1 was dissociated from T1 in a BDNF-dependent manner, which also causes decreases in the activities of Rho-signaling molecules such as RhoA, Rho-associated kinase, p21-activated kinase, and extracellular-signal regulated kinase1/2. Moreover, BDNF treatment resulted in the disappearance of stress fibers in the cells treated with lysophosphatidic acid, an activator of RhoA, and in morphological changes in cells. Furthermore, a competitive assay with cyan fluorescent protein fusion proteins of T1-specific sequences reduced the effects of BDNF. These results suggest that T1 regulates the Rho-signaling pathways and the actin cytoskeleton

Nucleotide Sequence and Characterization of the Broad-Host-Range Lactococcal Plasmid pWVO1

NARCIS (Netherlands)

Leenhouts, Cornelis; Tolner, Berend; Bron, Sierd; Kok, Jan; Venema, Gerhardus; Seegers, Jozef

The nucleotide sequence of the Lactococcus lactis broad-host-range plasmid pWVO1, replicating in both gram-positive and gram-negative bacteria, was determined. This analysis revealed four open reading frames (ORFs). ORF A appeared to encode a trans-acting 26.8-kDa protein (RepA), necessary for

RhoA determines disease progression by controlling neutrophil motility and restricting hyperresponsiveness

DEFF Research Database (Denmark)

Jennings, Richard T; Strengert, Monika; Hayes, Patti

2014-01-01

Neutrophil responses are central to host protection and inflammation. Neutrophil activation follows a two-step process where priming amplifies responses to activating stimuli. Priming is essential for life span extension, chemotaxis and respiratory burst activity. Here we show that the cytoskeletal...... organizer RhoA suppresses neutrophil priming via formins. Premature granule exocytosis in Rho-deficient neutrophils activated numerous signaling pathways and amplified superoxide generation. Deletion of Rho altered front-to-back coordination by simultaneously increasing uropod elongation, leading edge...... neutrophils exacerbated LPS-mediated lung injury, deleting Rho in innate immune cells was highly protective in Influenza A virus infection. Hence, Rho is a key regulator of disease progression by maintaining neutrophil quiescence and suppressing hyperresponsiveness....

RhoA/Rho-Kinase in the Cardiovascular System.

Science.gov (United States)

Shimokawa, Hiroaki; Sunamura, Shinichiro; Satoh, Kimio

2016-01-22

Twenty years ago, Rho-kinase was identified as an important downstream effector of the small GTP-binding protein, RhoA. Thereafter, a series of studies demonstrated the important roles of Rho-kinase in the cardiovascular system. The RhoA/Rho-kinase pathway is now widely known to play important roles in many cellular functions, including contraction, motility, proliferation, and apoptosis, and its excessive activity induces oxidative stress and promotes the development of cardiovascular diseases. Furthermore, the important role of Rho-kinase has been demonstrated in the pathogenesis of vasospasm, arteriosclerosis, ischemia/reperfusion injury, hypertension, pulmonary hypertension, and heart failure. Cyclophilin A is secreted by vascular smooth muscle cells and inflammatory cells and activated platelets in a Rho-kinase-dependent manner, playing important roles in a wide range of cardiovascular diseases. Thus, the RhoA/Rho-kinase pathway plays crucial roles under both physiological and pathological conditions and is an important therapeutic target in cardiovascular medicine. Recently, functional differences between ROCK1 and ROCK2 have been reported in vitro. ROCK1 is specifically cleaved by caspase-3, whereas granzyme B cleaves ROCK2. However, limited information is available on the functional differences and interactions between ROCK1 and ROCK2 in the cardiovascular system in vivo. Herein, we will review the recent advances about the importance of RhoA/Rho-kinase in the cardiovascular system. © 2016 American Heart Association, Inc.

Convergent use of RhoGAP toxins by eukaryotic parasites and bacterial pathogens.

Directory of Open Access Journals (Sweden)

Dominique Colinet

2007-12-01

Full Text Available Inactivation of host Rho GTPases is a widespread strategy employed by bacterial pathogens to manipulate mammalian cellular functions and avoid immune defenses. Some bacterial toxins mimic eukaryotic Rho GTPase-activating proteins (GAPs to inactivate mammalian GTPases, probably as a result of evolutionary convergence. An intriguing question remains whether eukaryotic pathogens or parasites may use endogenous GAPs as immune-suppressive toxins to target the same key genes as bacterial pathogens. Interestingly, a RhoGAP domain-containing protein, LbGAP, was recently characterized from the parasitoid wasp Leptopilina boulardi, and shown to protect parasitoid eggs from the immune response of Drosophila host larvae. We demonstrate here that LbGAP has structural characteristics of eukaryotic RhoGAPs but that it acts similarly to bacterial RhoGAP toxins in mammals. First, we show by immunocytochemistry that LbGAP enters Drosophila immune cells, plasmatocytes and lamellocytes, and that morphological changes in lamellocytes are correlated with the quantity of LbGAP they contain. Demonstration that LbGAP displays a GAP activity and specifically interacts with the active, GTP-bound form of the two Drosophila Rho GTPases Rac1 and Rac2, both required for successful encapsulation of Leptopilina eggs, was then achieved using biochemical tests, yeast two-hybrid analysis, and GST pull-down assays. In addition, we show that the overall structure of LbGAP is similar to that of eukaryotic RhoGAP domains, and we identify distinct residues involved in its interaction with Rac GTPases. Altogether, these results show that eukaryotic parasites can use endogenous RhoGAPs as virulence factors and that despite their differences in sequence and structure, eukaryotic and bacterial RhoGAP toxins are similarly used to target the same immune pathways in insects and mammals.

Mouse macrophages completely lacking Rho (RhoA, RhoB and RhoC) have severe lamellipodial retraction defects, but robust chemotactic navigation and increased motility

DEFF Research Database (Denmark)

Koenigs, Volker; Jennings, Richard; Vogl, Thomas

2014-01-01

RhoA is thought to be essential for coordination of the membrane protrusions and retractions required for immune cell motility and directed migration. Whether the subfamily of Rho (Ras homolog) GTPases (RhoA, RhoB and RhoC) is actually required for the directed migration of primary cells is diffi...

NMR characterization of weak interactions between RhoGDI2 and fragment screening hits.

Science.gov (United States)

Liu, Jiuyang; Gao, Jia; Li, Fudong; Ma, Rongsheng; Wei, Qingtao; Wang, Aidong; Wu, Jihui; Ruan, Ke

2017-01-01

The delineation of intrinsically weak interactions between novel targets and fragment screening hits has long limited the pace of hit-to-lead evolution. Rho guanine-nucleotide dissociation inhibitor 2 (RhoGDI2) is a novel target that lacks any chemical probes for the treatment of tumor metastasis. Protein-observed and ligand-observed NMR spectroscopy was used to characterize the weak interactions between RhoGDI2 and fragment screening hits. We identified three hits of RhoGDI2 using streamlined NMR fragment-based screening. The binding site residues were assigned using non-uniformly sampled C α - and H α -based three dimensional NMR spectra. The molecular docking to the proposed geranylgeranyl binding pocket of RhoGDI2 was guided by NMR restraints of chemical shift perturbations and ligand-observed transferred paramagnetic relaxation enhancement. We further validated the weak RhoGDI2-hit interactions using mutagenesis and structure-affinity analysis. Weak interactions between RhoGDI2 and fragment screening hits were delineated using an integrated NMR approach. Binders to RhoGDI2 as a potential anti-cancer target have been first reported, and their weak interactions were depicted using NMR spectroscopy. Our work highlights the powerfulness and the versatility of the integrative NMR techniques to provide valuable structural insight into the intrinsically weak interactions between RhoGDI2 and the fragment screening hits, which could hardly be conceived using other biochemical techniques. Copyright © 2016 Elsevier B.V. All rights reserved.

Yersinia outer protein YopE affects the actin cytoskeleton in Dictyostelium discoideum through targeting of multiple Rho family GTPases

LENUS (Irish Health Repository)

Vlahou, Georgia

2009-07-14

Abstract Background All human pathogenic Yersinia species share a virulence-associated type III secretion system that translocates Yersinia effector proteins into host cells to counteract infection-induced signaling responses and prevent phagocytosis. Dictyostelium discoideum has been recently used to study the effects of bacterial virulence factors produced by internalized pathogens. In this study we explored the potential of Dictyostelium as model organism for analyzing the effects of ectopically expressed Yersinia outer proteins (Yops). Results The Yersinia pseudotuberculosis virulence factors YopE, YopH, YopM and YopJ were expressed de novo within Dictyostelium and their effects on growth in axenic medium and on bacterial lawns were analyzed. No severe effect was observed for YopH, YopJ and YopM, but expression of YopE, which is a GTPase activating protein for Rho GTPases, was found to be highly detrimental. GFP-tagged YopE expressing cells had less conspicuous cortical actin accumulation and decreased amounts of F-actin. The actin polymerization response upon cAMP stimulation was impaired, although chemotaxis was unaffected. YopE also caused reduced uptake of yeast particles. These alterations are probably due to impaired Rac1 activation. We also found that YopE predominantly associates with intracellular membranes including the Golgi apparatus and inhibits the function of moderately overexpressed RacH. Conclusion The phenotype elicited by YopE in Dictyostelium can be explained, at least in part, by inactivation of one or more Rho family GTPases. It further demonstrates that the social amoeba Dictyostelium discoideum can be used as an efficient and easy-to-handle model organism in order to analyze the function of a translocated GAP protein of a human pathogen.

Expression of a Rho guanine nucleotide exchange factor, Ect2, in the developing mouse pituitary.

Science.gov (United States)

Islam, M S; Tsuji, T; Higashida, C; Takahashi, M; Higashida, H; Koizumi, K

2010-05-01

The pituitary gland is a highly mitotically active tissue after birth. Various cell types are known to undergo proliferation in the anterior pituitary. However, little is known about the mechanisms regulating mitotic activity in this tissue. When searching for genes specifically expressed in the pituitary gland among those that we previously screened in Drosophila, we found epithelial cell-transforming gene 2 (Ect2). Ect2 is a guanine nucleotide exchange factor for Rho GTPases, which is known to play an essential role in cytokinesis. Although there have been many cellular studies regarding the function of Ect2, the temporal and spatial expression patterns of Ect2 in vivo have not been determined. In the present study, we examined the postnatal developmental expression of Ect2 in the mouse pituitary. Enhanced Ect2 expression was detected in the mouse pituitary gland during the first 3 weeks after birth, which coincided well with the period of rapid pituitary expansion associated with increased growth rate. Immunostaining analysis showed that Ect2-expressing cells were distributed in the anterior and intermediate lobes, but not the posterior lobe, of the pituitary. These Ect2-expressing cells frequently incorporated the thymidine analogue, EdU (5-ethynyl-2'-deoxyuridine), indicating that these cells were mitotically active. Taken together, the results demonstrate the functional role of Ect2 in postnatal proliferating cells in the two lobes of the pituitary, thereby suggesting roles in developmental growth of the mammalian pituitary.

Comparative transcriptomics reveal host-specific nucleotide variation in entomophthoralean fungi

DEFF Research Database (Denmark)

de Fine Licht, Henrik Hjarvard; Jensen, Annette Bruun; Eilenberg, Jørgen

2017-01-01

of toxins that interfere with the host immune response. Phylogenetic comparison with the nonobligate generalist insect-pathogenic fungus Conidiobolus coronatus revealed a gene-family expansion of trehalase enzymes in E. muscae. The main sugar in insect haemolymph is trehalose, and efficient sugar...

High energy photoproduction of the rho and rho' vector mesons

International Nuclear Information System (INIS)

Bronstein, J.M.

1977-01-01

In an experiment in the broad band photon beam at Fermilab diffractive production of 2π + and 4π +- states from Be, Al, Cu, and Pb targets was observed. The 2π + data are dominated by the rho(770) and the 4π +- is dominated by the rho'(1500). The energy dependence of rho photoproduction from Be was measured, and no evidence was seen for energy variation of the forward cross section in the range 30 to 160 GeV. The forward cross section is consistent with its average value d sigma/dtlt. slash 0 = 3.42 +- 0.28 μb/GeV 2 over the entire range. For the /sub rho'// a mass of 1487 +- 20 MeV and a width of 675 +- 60 MeV are obtained. All quoted errors are statistical. A standard optical model analysis of the A dependence of the rho and rho'/ photoproduction yields the following results. f/sub rho'/ 2 /f/sub rho/ 2 = 3.7 +- 0.7, sigma /sub rho'//sigma /sub rho/ = 1.05 +- 0.18. Results for the photon coupling constants are in good agreement with GVMD and with the e + e - storage ring results. The approximate equality of the rho-nucleon and rho'-nucleon total cross sections is inconsistent with the diagonal version of GVMD and provides strong motivation for including transitions between different vector mesons in GVMD

AKAP13 Rho-GEF and PKD-binding domain deficient mice develop normally but have an abnormal response to β-adrenergic-induced cardiac hypertrophy.

Directory of Open Access Journals (Sweden)

Matthew J Spindler

Full Text Available A-kinase anchoring proteins (AKAPs are scaffolding molecules that coordinate and integrate G-protein signaling events to regulate development, physiology, and disease. One family member, AKAP13, encodes for multiple protein isoforms that contain binding sites for protein kinase A (PKA and D (PKD and an active Rho-guanine nucleotide exchange factor (Rho-GEF domain. In mice, AKAP13 is required for development as null embryos die by embryonic day 10.5 with cardiovascular phenotypes. Additionally, the AKAP13 Rho-GEF and PKD-binding domains mediate cardiomyocyte hypertrophy in cell culture. However, the requirements for the Rho-GEF and PKD-binding domains during development and cardiac hypertrophy are unknown.To determine if these AKAP13 protein domains are required for development, we used gene-trap events to create mutant mice that lacked the Rho-GEF and/or the protein kinase D-binding domains. Surprisingly, heterozygous matings produced mutant mice at Mendelian ratios that had normal viability and fertility. The adult mutant mice also had normal cardiac structure and electrocardiograms. To determine the role of these domains during β-adrenergic-induced cardiac hypertrophy, we stressed the mice with isoproterenol. We found that heart size was increased similarly in mice lacking the Rho-GEF and PKD-binding domains and wild-type controls. However, the mutant hearts had abnormal cardiac contractility as measured by fractional shortening and ejection fraction.These results indicate that the Rho-GEF and PKD-binding domains of AKAP13 are not required for mouse development, normal cardiac architecture, or β-adrenergic-induced cardiac hypertrophic remodeling. However, these domains regulate aspects of β-adrenergic-induced cardiac hypertrophy.

Measurement of exclusive $\\rho^{+}\\rho^{-}$ production in mid-virtuality two-photon interactions and study of the $\\gamma \\gamma^{*} \\to \\rho\\rho$ process at LEP

CERN Document Server

Achard, P.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M.G.; Anderhub, H.; Andreev, Valery P.; Anselmo, F.; Arefiev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay, L.; Baldew, S.V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillere, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B.L.; Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J.J.; Blyth, S.C.; Bobbink, G.J.; Bohm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J.G.; Brochu, F.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Chamizo, M.; Chang, Y.H.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G.M.; Chen, H.F.; Chen, H.S.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; de la Cruz, B.; Cucciarelli, S.; de Asmundis, R.; Deglon, P.; Debreczeni, J.; Degre, A.; Dehmelt, K.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M.T.; Duchesneau, D.; Duda, M.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.; Engler, A.; Eppling, F.J.; Extermann, P.; Falagan, M.A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fesefeldt, H.; Fiandrini, E.; Field, J.H.; Filthaut, F.; Fisher, P.H.; Fisher, W.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Iouri; Ganguli, S.N.; Garcia-Abia, Pablo; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z.F.; Grenier, Gerald Jean; Grimm, O.; Gruenewald, M.W.; Guida, M.; Gupta, V.K.; Gurtu, A.; Gutay, L.J.; Haas, D.; Hatzifotiadou, D.; Hebbeker, T.; Herve, Alain; Hirschfelder, J.; Hofer, H.; Hohlmann, M.; Holzner, G.; Hou, S.R.; Jin, B.N.; Jindal, P.; Jones, Lawrence W.; de Jong, P.; Josa-Mutuberria, I.; Kaur, M.; Kienzle-Focacci, M.N.; Kim, J.K.; Kirkby, Jasper; Kittel, W.; Klimentov, A.; Konig, A.C.; Kopal, M.; Koutsenko, V.; Kraber, M.; Kraemer, R.W.; Kruger, A.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Le Goff, J.M.; Leiste, R.; Levtchenko, M.; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C.H.; Lin, W.T.; Linde, F.L.; Lista, L.; Liu, Z.A.; Lohmann, W.; Longo, E.; Lu, Y.S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W.G.; Malgeri, L.; Malinin, A.; Mana, C.; Mans, J.; Martin, J.P.; Marzano, F.; Mazumdar, K.; McNeil, R.R.; Mele, S.; Merola, L.; Meschini, M.; Metzger, W.J.; Mihul, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G.B.; Muanza, G.S.; Muijs, A.J.M.; Musicar, B.; Musy, M.; Nagy, S.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Kluge, Hannelies; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.; Passaleva, G.; Patricelli, S.; Paul, Thomas Cantzon; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Piccolo, D.; Pierella, F.; Pioppi, M.; Piroue, P.A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofiev, D.; Rahal-Callot, G.; Rahaman, Mohammad Azizur; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P.G.; Ranieri, R.; Raspereza, A.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Riemann, S.; Riles, Keith; Roe, B.P.; Romero, L.; Rosca, A.; Rosemann, C.; Rosenbleck, C.; Rosier-Lees, S.; Roth, Stefan; Rubio, J.A.; Ruggiero, G.; Rykaczewski, H.; Sakharov, A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schafer, C.; Schegelsky, V.; Schopper, H.; Schotanus, D.J.; Sciacca, C.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.; Steuer, M.; Stickland, D.P.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L.Z.; Sushkov, S.; Suter, H.; Swain, J.D.; Szillasi, Z.; Tang, X.W.; Tarjan, P.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, Charles; Ting, Samuel C.C.; Ting, S.M.; Tonwar, S.C.; Toth, J.; Tully, C.; Tung, K.L.; Ulbricht, J.; Valente, E.; Van de Walle, R.T.; Vasquez, R.; Veszpremi, V.; Vesztergombi, G.; Vetlitsky, I.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobiev, I.; Vorobyov, A.A.; Wadhwa, M.; Wang, Q.; Wang, X.L.; Wang, Z.M.; Weber, M.; Wynhoff, S.; Xia, L.; Xu, Z.Z.; Yamamoto, J.; Yang, B.Z.; Yang, C.G.; Yang, H.J.; Yang, M.; Yeh, S.C.; Zalite, An.; Zalite, Yu.; Zhang, Z.P.; Zhao, J.; Zhu, G.Y.; Zhu, R.Y.; Zhuang, H.L.; Zichichi, A.; Zimmermann, B.; Zoller, M.

2005-01-01

Exclusive rho+rho- production in two-photon collisions between a quasi-real photon, gamma, and a mid-virtuality photon, gamma*, is studied with data collected at LEP at centre-of-mass energies root(s)=183-209GeV with a total integrated luminosity of 684.8pb^-1. The cross section of the gamma gamma* -> rho+ rho- process is determined as a function of the photon virtuality, Q^2, and the two-photon centre-of-mass energy, W_gg, in the kinematic region: 0.2GeV^2 rho rho process over the Q^2-region 0.2GeV^2 < Q^2 < 30 GeV^2.

[Effect of antepartum taurine supplementation in regulating the activity of Rho family factors and promoting the proliferation of neural stem cells in neonatal rats with fetal growth restriction].

Science.gov (United States)

Li, Xiang-Wen; Li, Fang; Liu, Jing; Wang, Yan; Fu, Wei

2016-11-01

To study the possible effect of antepartum taurine supplementation in regulating the activity of Rho family factors and promoting the proliferation of neural stem cells in neonatal rats with fetal growth restriction (FGR), and to provide a basis for antepartum taurine supplementation to promote brain development in children with FGR. A total of 24 pregnant Sprague-Dawley rats were randomly divided into three groups: control, FGR, and taurine (n=8 each ). A rat model of FGR was established by food restriction throughout pregnancy. RT-PCR, immunohistochemistry, and Western blot were used to measure the expression of the specific intracellular markers for neural stem cells fatty acid binding protein 7 (FABP7), Rho-associated coiled-coil containing protein kinase 2 (ROCK2), ras homolog gene family, member A (RhoA), and Ras-related C3 botulinum toxin substrate (Rac). The FGR group had significantly lower OD value of FABP7-positive cells and mRNA and protein expression of FABP7 than the control group, and the taurine group had significantly higher OD value of FABP7-positive cells and mRNA and protein expression of FABP7 than the FGR group (Ptaurine group had significantly higher mRNA expression of RhoA and ROCK2 than the control group and significantly lower expression than the FGR group (Ptaurine group had significantly higher mRNA expression of Rac than the FGR and control groups (Ptaurine group had significantly lower protein expression of RhoA and ROCK2 than the FGR group (Ptaurine supplementation can promote the proliferation of neural stem cells in rats with FGR, and its mechanism may be related to the regulation of the activity of Rho family factors.

Alteration of Pituitary Tumor Transforming Gene-1 Regulates Trophoblast Invasion via the Integrin/Rho-Family Signaling Pathway.

Directory of Open Access Journals (Sweden)

Seung Mook Lim

Full Text Available Trophoblast invasion ability is an important factor in early implantation and placental development. Recently, pituitary tumor transforming gene 1 (PTTG1 was shown to be involved in invasion and proliferation of cancer. However, the role of PTTG1 in trophoblast invasion remains unknown. Thus, in this study we analyzed PTTG1 expression in trophoblasts and its effect on trophoblast invasion activity and determined the mechanism through which PTTG1 regulates trophoblast invasion. Trophoblast proliferation and invasion abilities, regardless of PTTG1 expression, were analyzed by quantitative real-time polymerase chain reaction, fluorescence-activated cell sorting analysis, invasion assay, western blot, and zymography after treatment with small interfering RNA against PTTG1 (siPTTG1. Additionally, integrin/Rho-family signaling in trophoblasts by PTTG1 alteration was analyzed. Furthermore, the effect of PTTG1 on trophoblast invasion was evaluated by microRNA (miRNA mimic and inhibitor treatment. Trophoblast invasion was significantly reduced through decreased matrix metalloproteinase (MMP-2 and MMP-9 expression when PTTG1 expression was inhibited by siPTTG1 (p < 0.05. Furthermore, knockdown of PTTG1 increased expression of integrin alpha 4 (ITGA4, ITGA5, and integrin beta 1 (ITGB1; otherwise, RhoA expression was significantly decreased (p < 0.05. Treatment of miRNA-186-5p mimic and inhibitor controlled trophoblast invasion ability by altering PTTG1 and MMP expression. PTTG1 can control trophoblast invasion ability via regulation of MMP expression through integrin/Rho-family signaling. In addition, PTTG1 expression and its function were regulated by miRNA-186-5p. These results help in understanding the mechanism through which PTTG1 regulates trophoblast invasion and thereby implantation and placental development.

The small GTPase RhoH is an atypical regulator of haematopoietic cells

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Kubatzky Katharina F

2008-09-01

Full Text Available Abstract Rho GTPases are a distinct subfamily of the superfamily of Ras GTPases. The best-characterised members are RhoA, Rac and Cdc42 that regulate many diverse actions such as actin cytoskeleton reorganisation, adhesion, motility as well as cell proliferation, differentiation and gene transcription. Among the 20 members of that family, only Rac2 and RhoH show an expression restricted to the haematopoietic lineage. RhoH was first discovered in 1995 as a fusion transcript with the transcriptional repressor LAZ3/BCL6. It was therefore initially named translation three four (TTF but later on renamed RhoH due to its close relationship to the Ras/Rho family of GTPases. Since then, RhoH has been implicated in human cancer as the gene is subject to somatic hypermutation and by the detection of RHOH as a translocation partner for LAZ3/BCL6 or other genes in human lymphomas. Underexpression of RhoH is found in hairy cell leukaemia and acute myeloid leukaemia. Some of the amino acids that are crucial for GTPase activity are mutated in RhoH so that the protein is a GTPase-deficient, so-called atypical Rho GTPase. Therefore other mechanisms of regulating RhoH activity have been described. These include regulation at the mRNA level and tyrosine phosphorylation of the protein's unique ITAM-like motif. The C-terminal CaaX box of RhoH is mainly a target for farnesyl-transferase but can also be modified by geranylgeranyl-transferase. Isoprenylation of RhoH and changes in subcellular localisation may be an additional factor to fine-tune signalling. Little is currently known about its signalling, regulation or interaction partners. Recent studies have shown that RhoH negatively influences the proliferation and homing of murine haematopoietic progenitor cells, presumably by acting as an antagonist for Rac1. In leukocytes, RhoH is needed to keep the cells in a resting, non-adhesive state, but the exact mechanism has yet to be elucidated. RhoH has also been

RhoA/Rho Kinase Mediates Neuronal Death Through Regulating cPLA2 Activation.

Science.gov (United States)

Wu, Xiangbing; Walker, Chandler L; Lu, Qingbo; Wu, Wei; Eddelman, Daniel B; Parish, Jonathan M; Xu, Xiao-Ming

2017-11-01

Activation of RhoA/Rho kinase leads to growth cone collapse and neurite retraction. Although RhoA/Rho kinase inhibition has been shown to improve axon regeneration, remyelination and functional recovery, its role in neuronal cell death remains unclear. To determine whether RhoA/Rho kinase played a role in neuronal death after injury, we investigated the relationship between RhoA/Rho kinase and cytosolic phospholipase A 2 (cPLA 2 ), a lipase that mediates inflammation and cell death, using an in vitro neuronal death model and an in vivo contusive spinal cord injury model performed at the 10th thoracic (T10) vertebral level. We found that co-administration of TNF-α and glutamate induced spinal neuron death, and activation of RhoA, Rho kinase and cPLA 2 . Inhibition of RhoA, Rho kinase and cPLA 2 significantly reduced TNF-α/glutamate-induced cell death by 33, 52 and 43 %, respectively (p < 0.001). Inhibition of RhoA and Rho kinase also significantly downregulated cPLA 2 activation by 66 and 60 %, respectively (p < 0.01). Furthermore, inhibition of RhoA and Rho kinase reduced the release of arachidonic acid, a downstream substrate of cPLA 2 . The immunofluorescence staining showed that ROCK 1 or ROCK 2 , two isoforms of Rho kinase, was co-localized with cPLA 2 in neuronal cytoplasm. Interestingly, co-immunoprecipitation (Co-IP) assay showed that ROCK 1 or ROCK 2 bonded directly with cPLA 2 and phospho-cPLA 2 . When the Rho kinase inhibitor Y27632 was applied in mice with T10 contusion injury, it significantly decreased cPLA 2 activation and expression and reduced injury-induced apoptosis at and close to the lesion site. Taken together, our results reveal a novel mechanism of RhoA/Rho kinase-mediated neuronal death through regulating cPLA 2 activation.

Rasp21 sequences opposite the nucleotide binding pocket are required for GRF-mediated nucleotide release

DEFF Research Database (Denmark)

Leonardsen, L; DeClue, J E; Lybaek, H

1996-01-01

The substrate requirements for the catalytic activity of the mouse Cdc25 homolog Guanine nucleotide Release Factor, GRF, were determined using the catalytic domain of GRF expressed in insect cells and E. coli expressed H-Ras mutants. We found a requirement for the loop 7 residues in Ras (amino ac...... and the human Ras like proteins RhoA, Rap1A, Rac1 and G25K revealed a strict Ras specificity; of these only S. pombe Ras was GRF sensitive....

Rho GTPases in ameloblast differentiation

Directory of Open Access Journals (Sweden)

Keishi Otsu

2016-05-01

Full Text Available During tooth development, ameloblasts differentiate from inner enamel epithelial cells to enamel-forming cells by modulating the signal pathways mediating epithelial–mesenchymal interaction and a cell-autonomous gene network. The differentiation process of epithelial cells is characterized by marked changes in their morphology and polarity, accompanied by dynamic cytoskeletal reorganization and changes in cell–cell and cell–matrix adhesion over time. Functional ameloblasts are tall, columnar, polarized cells that synthesize and secrete enamel-specific proteins. After deposition of the full thickness of enamel matrix, ameloblasts become smaller and regulate enamel maturation. Recent significant advances in the fields of molecular biology and genetics have improved our understanding of the regulatory mechanism of the ameloblast cell life cycle, mediated by the Rho family of small GTPases. They act as intracellular molecular switch that transduce signals from extracellular stimuli to the actin cytoskeleton and the nucleus. In our review, we summarize studies that provide current evidence for Rho GTPases and their involvement in ameloblast differentiation. In addition to the Rho GTPases themselves, their downstream effectors and upstream regulators have also been implicated in ameloblast differentiation.

Identification of a GTP-bound Rho specific scFv molecular sensor by phage display selection

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Chinestra Patrick

2008-03-01

Full Text Available Abstract Background The Rho GTPases A, B and C proteins, members of the Rho family whose activity is regulated by GDP/GTP cycling, function in many cellular pathways controlling proliferation and have recently been implicated in tumorigenesis. Although overexpression of Rho GTPases has been correlated with tumorigenesis, only their GTP-bound forms are able to activate the signalling pathways implicated in tumorigenesis. Thus, the focus of much recent research has been to identify biological tools capable of quantifying the level of cellular GTP-bound Rho, or determining the subcellular location of activation. However useful, these tools used to study the mechanism of Rho activation still have limitations. The aim of the present work was to employ phage display to identify a conformationally-specific single chain fragment variable (scFv that recognizes the active, GTP-bound, form of Rho GTPases and is able to discriminate it from the inactive, GDP-bound, Rho in endogenous settings. Results After five rounds of phage selection using a constitutively activated mutant of RhoB (RhoBQ63L, three scFvs (A8, C1 and D11 were selected for subsequent analysis. Further biochemical characterization was pursued for the single clone, C1, exhibiting an scFv structure. C1 was selective for the GTP-bound form of RhoA, RhoB, as well as RhoC, and failed to recognize GTP-loaded Rac1 or Cdc42, two other members of the Rho family. To enhance its production, soluble C1 was expressed in fusion with the N-terminal domain of phage protein pIII (scFv C1-N1N2, it appeared specifically associated with GTP-loaded recombinant RhoA and RhoB via immunoprecipitation, and endogenous activated Rho in HeLa cells as determined by immunofluorescence. Conclusion We identified an antibody, C1-N1N2, specific for the GTP-bound form of RhoB from a phage library, and confirmed its specificity towards GTP-bound RhoA and RhoC, as well as RhoB. The success of C1-N1N2 in discriminating activated

Small G proteins in insulin action: Rab and Rho families at the crossroads of signal transduction and GLUT4 vesicle traffic.

Science.gov (United States)

Ishikura, S; Koshkina, A; Klip, A

2008-01-01

Insulin stimulates glucose uptake into muscle and adipose tissues through glucose transporter 4 (GLUT4). GLUT4 cycles between the intracellular compartments and the plasma membrane. GLUT4 traffic-regulating insulin signals are largely within the insulin receptor-insulin receptor substrate-phosphatidylinositol 3-kinase (IR-IRS-PI3K) axis. In muscle cells, insulin signal bifurcates downstream of the PI3K into one arm leading to the activation of the Ser/Thr kinases Akt and atypical protein kinase C, and another leading to the activation of Rho family protein Rac1 leading to actin remodelling. Activated Akt inactivates AS160, a GTPase-activating protein for Rab family small G proteins. Here we review the roles of Rab and Rho proteins, particularly Rab substrates of AS160 and Rac1, in insulin-stimulated GLUT4 traffic. We discuss: (1) how distinct steps in GLUT4 traffic may be regulated by discrete Rab proteins, and (2) the importance of Rac1 activation in insulin-induced actin remodelling in muscle cells, a key element for the net gain in surface GLUT4.

Enhancing the Homestay: Study Abroad from the Host Family's Perspective.

Science.gov (United States)

Knight, Susan M.; Schmidt-Rinehart, Barbara C.

2002-01-01

Analyzes interview data with 24 host families of home stay students in study abroad situations to determine salient, recurring topics. Discusses the study design and major themes that emerged. Concludes with hosts' recommendations on how students, programs, and the native families themselves can work together to enhance the homestay experience.…

Implications of Rho GTPase signaling in glioma cell invasion and tumor progression

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Shannon Patricia Fortin Ensign

2013-10-01

Full Text Available Glioblastoma (GB is the most malignant of primary adult brain tumors, characterized by a highly locally-invasive cell population, as well as abundant proliferative cells, neoangiogenesis, and necrosis. Clinical intervention with chemotherapy or radiation may either promote or establish an environment for manifestation of invasive behavior. Understanding the molecular drivers of invasion in the context of glioma progression may be insightful in directing new treatments for patients with GB. Here, we review current knowledge on Rho family GTPases, their aberrant regulation in GB, and their effect on GB cell invasion and tumor progression. Rho GTPases are modulators of cell migration through effects on actin cytoskeleton rearrangement; in non-neoplastic tissue, expression and activation of Rho GTPases are normally under tight regulation. In GB, Rho GTPases are deregulated, often via hyperactivity or overexpression of their activators, Rho GEFs. Downstream effectors of Rho GTPases have been shown to promote invasiveness and, importantly, glioma cell survival. The study of aberrant Rho GTPase signaling in GB is thus an important investigation of cell invasion as well as treatment resistance and disease progression.

BAR domain proteins regulate Rho GTPase signaling.

Science.gov (United States)

Aspenström, Pontus

2014-01-01

BAR proteins comprise a heterogeneous group of multi-domain proteins with diverse biological functions. The common denominator is the Bin-Amphiphysin-Rvs (BAR) domain that not only confers targeting to lipid bilayers, but also provides scaffolding to mold lipid membranes into concave or convex surfaces. This function of BAR proteins is an important determinant in the dynamic reconstruction of membrane vesicles, as well as of the plasma membrane. Several BAR proteins function as linkers between cytoskeletal regulation and membrane dynamics. These links are provided by direct interactions between BAR proteins and actin-nucleation-promoting factors of the Wiskott-Aldrich syndrome protein family and the Diaphanous-related formins. The Rho GTPases are key factors for orchestration of this intricate interplay. This review describes how BAR proteins regulate the activity of Rho GTPases, as well as how Rho GTPases regulate the function of BAR proteins. This mutual collaboration is a central factor in the regulation of vital cellular processes, such as cell migration, cytokinesis, intracellular transport, endocytosis, and exocytosis.

The Role of RhoA, RhoB and RhoC GTPases in Cell Morphology, Proliferation and Migration in Human Cytomegalovirus (HCMV Infected Glioblastoma Cells

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Melpomeni Tseliou

2016-01-01

Full Text Available Background/Aims: Rho GTPases are crucial regulators of the actin cytoskeleton, membrane trafficking and cell signaling and their importance in cell migration and invasion is well- established. The human cytomegalovirus (HCMV is a widespread pathogen responsible for generally asymptomatic and persistent infections in healthy people. Recent evidence indicates that HCMV gene products are expressed in over 90% of malignant type glioblastomas (GBM. In addition, the HCMV Immediate Early-1 protein (IE1 is expressed in >90% of tumors analyzed. Methods: RhoA, RhoB and RhoC were individually depleted in U373MG glioblastoma cells as well as U373MG cells stably expressing the HCMV IE1 protein (named U373MG-IE1 cells shRNA lentivirus vectors. Cell proliferation assays, migration as well as wound-healing assays were performed in uninfected and HCMV-infected cells. Results: The depletion of RhoA, RhoB and RhoC protein resulted in significant alterations in the morphology of the uninfected cells, which were further enhanced by the cytopathic effect caused by HCMV. Furthermore, in the absence or presence of HCMV, the knockdown of RhoB and RhoC proteins decreased the proliferation rate of the parental and the IE1-expressing glioblastoma cells, whereas the knockdown of RhoA protein in the HCMV infected cell lines restored their proliferation rate. In addition, wound healing assays in U373MG cells revealed that depletion of RhoA, RhoB and RhoC differentially reduced their migration rate, even in the presence or the absence of HCMV. Conclusion: Collectively, these data show for the first time a differential implication of Rho GTPases in morphology, proliferation rate and motility of human glioblastoma cells during HCMV infection, further supporting an oncomodulatory role of HCMV depending on the Rho isoforms' state.

Host Families Matter: The Homestay Manual.

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Peace Corps, Washington, DC. Information Collection and Exchange Div.

This manual provides guidelines, sample documents, and sample lesson plans for the trainers, trainees, and host families involved in homestays for Peace Corps volunteers. The manual contains 11 sections that deal with the following topics: (1) introduction; (2) policy, timelines, and responsibilities; (3) medical and financial issues; (4) host…

Rho GTPases, their post-translational modifications, disease-associated mutations and pharmacological inhibitors.

Science.gov (United States)

Olson, Michael F

2018-05-04

The 20 members of the Rho GTPase family are key regulators of a wide-variety of biological activities. In response to activation, they signal via downstream effector proteins to induce dynamic alterations in the organization of the actomyosin cytoskeleton. In this review, post-translational modifications, mechanisms of dysregulation identified in human pathological conditions, and the ways that Rho GTPases might be targeted for chemotherapy will be discussed.

Home on the Range: Host Families for Developmental Disabilities in Wyoming.

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Walling, Teresa; Potts, Bridget; Fortune, Jon; Cobb, Ginny L.; Fortune, Barbara

This report describes the outcomes of a Wyoming program that provides host families for individuals with developmental disabilities. Host families work with certified Medicaid providers of home and community-based services for people with developmental disabilities and provide residential habilitation to an adult who is accepted as a member of…

The interdependence of the Rho GTPases and apicobasal cell polarity.

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Mack, Natalie Ann; Georgiou, Marios

2014-01-01

Signaling via the Rho GTPases provides crucial regulation of numerous cell polarization events, including apicobasal (AB) polarity, polarized cell migration, polarized cell division and neuronal polarity. Here we review the relationships between the Rho family GTPases and epithelial AB polarization events, focusing on the 3 best-characterized members: Rho, Rac and Cdc42. We discuss a multitude of processes that are important for AB polarization, including lumen formation, apical membrane specification, cell-cell junction assembly and maintenance, as well as tissue polarity. Our discussions aim to highlight the immensely complex regulatory mechanisms that encompass Rho GTPase signaling during AB polarization. More specifically, in this review we discuss several emerging common themes, that include: 1) the need for Rho GTPase activities to be carefully balanced in both a spatial and temporal manner through a multitude of mechanisms; 2) the existence of signaling feedback loops and crosstalk to create robust cellular responses; and 3) the frequent multifunctionality that exists among AB polarity regulators. Regarding this latter theme, we provide further discussion of the potential plasticity of the cell polarity machinery and as a result the possible implications for human disease.

Loss of RhoB expression enhances the myelodysplastic phenotype of mammalian diaphanous-related Formin mDia1 knockout mice.

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Aaron D DeWard

Full Text Available Myelodysplastic syndrome (MDS is characterized by ineffective hematopoiesis and hyperplastic bone marrow. Complete loss or interstitial deletions of the long arm of chromosome 5 occur frequently in MDS. One candidate tumor suppressor on 5q is the mammalian Diaphanous (mDia-related formin mDia1, encoded by DIAPH1 (5q31.3. mDia-family formins act as effectors for Rho-family small GTP-binding proteins including RhoB, which has also been shown to possess tumor suppressor activity. Mice lacking the Drf1 gene that encodes mDia1 develop age-dependent myelodysplastic features. We crossed mDia1 and RhoB knockout mice to test whether the additional loss of RhoB expression would compound the myelodysplastic phenotype. Drf1(-/-RhoB(-/- mice are fertile and develop normally. Relative to age-matched Drf1(-/-RhoB(+/- mice, the age of myelodysplasia onset was earlier in Drf1(-/-RhoB(-/- animals--including abnormally shaped erythrocytes, splenomegaly, and extramedullary hematopoiesis. In addition, we observed a statistically significant increase in the number of activated monocytes/macrophages in both the spleen and bone marrow of Drf1(-/-RhoB(-/- mice relative to Drf1(-/-RhoB(+/- mice. These data suggest a role for RhoB-regulated mDia1 in the regulation of hematopoietic progenitor cells.

Arhgap28 is a RhoGAP that inactivates RhoA and downregulates stress fibers.

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Ching-Yan Chloé Yeung

Full Text Available The small GTPase RhoA is a major regulator of actin reorganization during the formation of stress fibers; thus identifying molecules that regulate Rho activity is necessary for a complete understanding of the mechanisms that determine cell contractility. Here, we have identified Arhgap28 as a Rho GTPase activating protein (RhoGAP that switches RhoA to its inactive form. We generated an Arhgap28-LacZ reporter mouse that revealed gene expression in soft tissues at E12.5, pre-bone structures of the limb at E15.5, and prominent expression restricted mostly to ribs and limb long bones at E18.5 days of development. Expression of recombinant Arhgap28-V5 in human osteosarcoma SaOS-2 cells caused a reduction in the basal level of RhoA activation and disruption of actin stress fibers. Extracellular matrix assembly studies using a 3-dimensional cell culture system showed that Arhgap28 was upregulated during Rho-dependent assembly of the ECM. Taken together, these observations led to the hypothesis that an Arhgap28 knockout mouse model would show a connective tissue phenotype, perhaps affecting bone. Arhgap28-null mice were viable and appeared normal, suggesting that there could be compensation from other RhoGAPs. Indeed, we showed that expression of Arhgap6 (a closely related RhoGAP was upregulated in Arhgap28-null bone tissue. An upregulation in RhoA expression was also detected suggesting that Arhgap28 may be able to additionally regulate Rho signaling at a transcriptional level. Microarray analyses revealed that Col2a1, Col9a1, Matn3, and Comp that encode extracellular matrix proteins were downregulated in Arhgap28-null bone. Although mutations in these genes cause bone dysplasias no bone phenotype was detected in the Arhgap-28 null mice. Together, these data suggest that the regulation of Rho by RhoGAPs, including Arhgap28, during the assembly and development of mechanically strong tissues is complex and may involve multiple RhoGAPs.

Rho family GTP binding proteins are involved in the regulatory volume decrease process in NIH3T3 mouse fibroblasts

DEFF Research Database (Denmark)

Pedersen, Stine F; Beisner, Kristine H; Willumsen, Berthe M

2002-01-01

The role of Rho GTPases in the regulatory volume decrease (RVD) process following osmotic cell swelling is controversial and has so far only been investigated for the swelling-activated Cl- efflux. We investigated the involvement of RhoA in the RVD process in NIH3T3 mouse fibroblasts, using wild......-type cells and three clones expressing constitutively active RhoA (RhoAV14). RhoAV14 expression resulted in an up to fourfold increase in the rate of RVD, measured by large-angle light scattering. The increase in RVD rate correlated with RhoAV14 expression. RVD in wild-type cells was unaffected by the Rho...

ARHGEF7 (Beta-PIX acts as guanine nucleotide exchange factor for leucine-rich repeat kinase 2.

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Karina Haebig

Full Text Available BACKGROUND: Mutations within the leucine-rich repeat kinase 2 (LRRK2 gene are a common cause of familial and sporadic Parkinson's disease. The multidomain protein LRRK2 exhibits overall low GTPase and kinase activity in vitro. METHODOLOGY/PRINCIPAL FINDINGS: Here, we show that the rho guanine nucleotide exchange factor ARHGEF7 and the small GTPase CDC42 are interacting with LRRK2 in vitro and in vivo. GTPase activity of full-length LRRK2 increases in the presence of recombinant ARHGEF7. Interestingly, LRRK2 phosphorylates ARHGEF7 in vitro at previously unknown phosphorylation sites. We provide evidence that ARHGEF7 might act as a guanine nucleotide exchange factor for LRRK2 and that R1441C mutant LRRK2 with reduced GTP hydrolysis activity also shows reduced binding to ARHGEF7. CONCLUSIONS/SIGNIFICANCE: Downstream effects of phosphorylation of ARHGEF7 through LRRK2 could be (i a feedback control mechanism for LRRK2 activity as well as (ii an impact of LRRK2 on actin cytoskeleton regulation. A newly identified familial mutation N1437S, localized within the GTPase domain of LRRK2, further underlines the importance of the GTPase domain of LRRK2 in Parkinson's disease pathogenesis.

Measurement of Exclusive $\\rho^+ \\rho^-$ Production in High-$Q^2$ Two-Photon Collisions at LEP

CERN Document Server

Achard, P.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M.G.; Anderhub, H.; Andreev, Valery P.; Anselmo, F.; Arefev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay, L.; Baldew, S.V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillere, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B.L.; Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J.J.; Blyth, S.C.; Bobbink, G.J.; Bohm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J.G.; Brochu, F.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Chamizo, M.; Chang, Y.H.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G.M.; Chen, H.F.; Chen, H.S.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; de la Cruz, B.; Cucciarelli, S.; van Dalen, J.A.; de Asmundis, R.; Deglon, P.; Debreczeni, J.; Degre, A.; Dehmelt, K.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M.T.; Duchesneau, D.; Duda, M.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.; Engler, A.; Eppling, F.J.; Extermann, P.; Falagan, M.A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fesefeldt, H.; Fiandrini, E.; Field, J.H.; Filthaut, F.; Fisher, P.H.; Fisher, W.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Iouri; Ganguli, S.N.; Garcia-Abia, Pablo; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z.F.; Grenier, Gerald Jean; Grimm, O.; Gruenewald, M.W.; Guida, M.; Gupta, V.K.; Gurtu, A.; Gutay, L.J.; Haas, D.; Hatzifotiadou, D.; Hebbeker, T.; Herve, Alain; Hirschfelder, J.; Hofer, H.; Hohlmann, M.; Holzner, G.; Hou, S.R.; Hu, Y.; Jin, B.N.; Jones, Lawrence W.; de Jong, P.; Josa-Mutuberria, I.; Kaur, M.; Kienzle-Focacci, M.N.; Kim, J.K.; Kirkby, Jasper; Kittel, W.; Klimentov, A.; Konig, A.C.; Kopal, M.; Koutsenko, V.; Kraber, M.; Kraemer, R.W.; Kruger, A.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Le Goff, J.M.; Leiste, R.; Levtchenko, M.; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C.H.; Lin, W.T.; Linde, F.L.; Lista, L.; Liu, Z.A.; Lohmann, W.; Longo, E.; Lu, Y.S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W.G.; Malgeri, L.; Malinin, A.; Mana, C.; Mans, J.; Martin, J.P.; Marzano, F.; Mazumdar, K.; McNeil, R.R.; Mele, S.; Merola, L.; Meschini, M.; Metzger, W.J.; Mihul, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G.B.; Muanza, G.S.; Muijs, A.J.M.; Musicar, B.; Musy, M.; Nagy, S.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Kluge, Hannelies; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.; Passaleva, G.; Patricelli, S.; Paul, Thomas Cantzon; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.; Pioppi, M.; Piroue, P.A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofev, D.; Quartieri, J.; Rahal-Callot, G.; Rahaman, Mohammad Azizur; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P.G.; Ranieri, R.; Raspereza, A.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Riemann, S.; Riles, Keith; Roe, B.P.; Romero, L.; Rosca, A.; Rosemann, C.; Rosenbleck, C.; Rosier-Lees, S.; Roth, Stefan; Rubio, J.A.; Ruggiero, G.; Rykaczewski, H.; Sakharov, A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schafer, C.; Schegelsky, V.; Schopper, H.; Schotanus, D.J.; Sciacca, C.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.; Steuer, M.; Stickland, D.P.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L.Z.; Sushkov, S.; Suter, H.; Swain, J.D.; Szillasi, Z.; Tang, X.W.; Tarjan, P.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, Charles; Ting, Samuel C.C.; Ting, S.M.; Tonwar, S.C.; Toth, J.; Tully, C.; Tung, K.L.; Ulbricht, J.; Valente, E.; Van de Walle, R.T.; Vasquez, R.; Veszpremi, V.; Vesztergombi, G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobev, I.; Vorobyov, A.A.; Wadhwa, M.; Wang, Q.; Wang, X.L.; Wang, Z.M.; Weber, M.; Wilkens, H.; Wynhoff, S.; Xia, L.; Xu, Z.Z.; Yamamoto, J.; Yang, B.Z.; Yang, C.G.; Yang, H.J.; Yang, M.; Yeh, S.C.; Zalite, An.; Zalite, Yu.; Zhang, Z.P.; Zhao, J.; Zhu, G.Y.; Zhu, R.Y.; Zhuang, H.L.; Zichichi, A.; Zimmermann, B.; Zoller, M.

2004-01-01

Exclusive rho^+ rho^- production in two-photon collisions involving a single highly-virtual photon is studied with data collected at LEP at centre-of-mass energies 89 GeV rho^+ rho^- is determined as a function of the photon virtuality, Q^2, and the two-photon centre-of-mass energy, W_gg, in the kinematic region: 1.2 GeV^2 rho^0 rho^0, measured in the same kinematic region by L3, and to have similar W_gg and Q^2 dependences.

Effects of chronic Δ9-tetrahydrocannabinol treatment on Rho/Rho-kinase signalization pathway in mouse brain

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Halil Mahir Kaplan

2017-11-01

Full Text Available Δ9-Tetrahydrocannabinol (Δ9-THC shows its effects by activating cannabinoid receptors which are on some tissues and neurons. Cannabinoid systems have role on cell proliferation and development of neurons. Furthermore, it is interesting that cannabinoid system and rho/rho-kinase signalization pathway, which have important role on cell development and proliferation, may have role on neuron proliferation and development together. Thus, a study is planned to investigate rhoA and rho-kinase enzyme expressions and their activities in the brain of chronic Δ9-THC treated mice. One group of mice are treated with Δ9-THC once to see effects of acute treatment. Another group of mice are treated with Δ9-THC three times per day for one month. After this period, rhoA and rho-kinase enzyme expressions and their activities in mice brains are analyzed by ELISA method. Chronic administration of Δ9-THC decreased the expression of rhoA while acute treatment has no meaningful effect on it. Administration of Δ9-THC did not affect expression of rho-kinase on both chronic and acute treatment. Administration of Δ9-THC increased rho-kinase activity on both chronic and acute treatment, however, chronic treatment decreased its activity with respect to acute treatment. This study showed that chronic Δ9-THC treatment down-regulated rhoA expression and did not change the expression level of rho-kinase which is downstream effector of rhoA. However, it elevated the rho-kinase activity. Δ9-THC induced down-regulation of rhoA may cause elevation of cypin expression and may have benefit on cypin related diseases. Furthermore, use of rho-kinase inhibitors and Δ9-THC together can be useful on rho-kinase related diseases.

A Point Mutation in p190A RhoGAP Affects Ciliogenesis and Leads to Glomerulocystic Kidney Defects.

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Katherine Stewart

2016-02-01

Full Text Available Rho family GTPases act as molecular switches regulating actin cytoskeleton dynamics. Attenuation of their signaling capacity is provided by GTPase-activating proteins (GAPs, including p190A, that promote the intrinsic GTPase activity of Rho proteins. In the current study we have performed a small-scale ENU mutagenesis screen and identified a novel loss of function allele of the p190A gene Arhgap35, which introduces a Leu1396 to Gln substitution in the GAP domain. This results in decreased GAP activity for the prototypical Rho-family members, RhoA and Rac1, likely due to disrupted ordering of the Rho binding surface. Consequently, Arhgap35-deficient animals exhibit hypoplastic and glomerulocystic kidneys. Investigation into the cystic phenotype shows that p190A is required for appropriate primary cilium formation in renal nephrons. P190A specifically localizes to the base of the cilia to permit axoneme elongation, which requires a functional GAP domain. Pharmacological manipulations further reveal that inhibition of either Rho kinase (ROCK or F-actin polymerization is able to rescue the ciliogenesis defects observed upon loss of p190A activity. We propose a model in which p190A acts as a modulator of Rho GTPases in a localized area around the cilia to permit the dynamic actin rearrangement required for cilia elongation. Together, our results establish an unexpected link between Rho GTPase regulation, ciliogenesis and glomerulocystic kidney disease.

Silencing of RhoA and RhoC expression by RNA interference suppresses human colorectal carcinoma growth in vivo

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Wang Haibo

2010-09-01

Full Text Available Abstract Background RhoA and RhoC have been proved to be over-expressed in many solid cancers, including colorectal cancer. The reduction of RhoA and RhoC expression by RNA interference (RNAi resulted growth inhibition of cancer cells. The present study was to evaluate the effect of silencing of RhoA and RhoC expression by RNAi on growth of human colorectal carcinoma (CRC in tumor-bearing nude mice in vivo. Methods To establish HCT116 cell transplantable model, the nude mice were subcutaneously inoculated with 1.0 × 107 HCT116 cells and kept growing till the tumor xenografts reached 5-7 mm in diameter. Then the mice were randomly assigned to three groups(seven mice in each group: (1 normal saline(NS group, (2replication-defective recombinant adenovirus carrying the negative control shRNA (Ad-HK group and (3replication-defective recombinant adenovirus carrying the 4-tandem linked RhoA and RhoC shRNAs (Ad-RhoA-RhoC group. Ad-HK (4 × 108 pfu, 30 ul/mouse, Ad-RhoA-RhoC (4 × 108 pfu, 30 ul/mouse or PBS (30 ul/mouse was injected intratumorally four times once every other day. The weight and volumes of tumor xenografts were recorded. The levels of RhoA and RhoC mRNA transcripts and proteins in tumor xenografts were detected by reverse quantitative transcription polymerase chain reaction (QRT-PCR and immunohistochemical staining respectively. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL assay was used to detect the death of cells. Results The xenografts in mice could be seen at 5th day from the implantation of HCT116 cells and all had reached 5-7 mm in size at 9th day. After injection intratumorally, the growth speed of tumor xenografts in Ad-RhoA-RhoC group was significantly delayed compared with those in NS and Ad-HK group(P RhoA and RhoC reduced more in Ad-RhoA-RhoC group than those in NS and Ad-HK group. The relative RhoA and RhoC mRNA transcripts were decreased to 48% and 43% respectively (P RhoA and Rho

The Bcl-2 Family in Host-Virus Interactions.

Science.gov (United States)

Kvansakul, Marc; Caria, Sofia; Hinds, Mark G

2017-10-06

Members of the B cell lymphoma-2 (Bcl-2) family are pivotal arbiters of mitochondrially mediated apoptosis, a process of fundamental importance during tissue development, homeostasis, and disease. At the structural and mechanistic level, the mammalian members of the Bcl-2 family are increasingly well understood, with their interplay ultimately deciding the fate of a cell. Dysregulation of Bcl-2-mediated apoptosis underlies a plethora of diseases, and numerous viruses have acquired homologs of Bcl-2 to subvert host cell apoptosis and autophagy to prevent premature death of an infected cell. Here we review the structural biology, interactions, and mechanisms of action of virus-encoded Bcl-2 proteins, and how they impact on host-virus interactions to ultimately enable successful establishment and propagation of viral infections.

Rnd3 induces stress fibres in endothelial cells through RhoB

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Undine Gottesbühren

2012-12-01

Rnd proteins are atypical Rho family proteins that do not hydrolyse GTP and are instead regulated by expression levels and post-translational modifications. Rnd1 and Rnd3/RhoE induce loss of actin stress fibres and cell rounding in multiple cell types, whereas responses to Rnd2 are more variable. Here we report the responses of endothelial cells to Rnd proteins. Rnd3 induces a very transient decrease in stress fibres but subsequently stimulates a strong increase in stress fibres, in contrast to the reduction observed in other cell types. Rnd2 also increases stress fibres whereas Rnd1 induces a loss of stress fibres and weakening of cell–cell junctions. Rnd3 does not act through any of its known signalling partners and does not need to associate with membranes to increase stress fibres. Instead, it acts by increasing RhoB expression, which is then required for Rnd3-induced stress fibre assembly. Rnd2 also increases RhoB levels. These data indicate that the cytoskeletal response to Rnd3 expression is dependent on cell type and context, and identify regulation of RhoB as a new mechanism for Rnd proteins to affect the actin cytoskeleton.

A bacterial cytotoxin identifies the RhoA exchange factor Net1 as a key effector in the response to DNA damage.

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Lina Guerra

Full Text Available BACKGROUND: Exposure of adherent cells to DNA damaging agents, such as the bacterial cytolethal distending toxin (CDT or ionizing radiations (IR, activates the small GTPase RhoA, which promotes the formation of actin stress fibers and delays cell death. The signalling intermediates that regulate RhoA activation and promote cell survival are unknown. PRINCIPAL FINDINGS: We demonstrate that the nuclear RhoA-specific Guanine nucleotide Exchange Factor (GEF Net1 becomes dephosphorylated at a critical inhibitory site in cells exposed to CDT or IR. Expression of a dominant negative Net1 or Net1 knock down by iRNA prevented RhoA activation, inhibited the formation of stress fibers, and enhanced cell death, indicating that Net1 activation is required for this RhoA-mediated responses to genotoxic stress. The Net1 and RhoA-dependent signals involved activation of the Mitogen-Activated Protein Kinase p38 and its downstream target MAPK-activated protein kinase 2. SIGNIFICANCE: Our data highlight the importance of Net1 in controlling RhoA and p38 MAPK mediated cell survival in cells exposed to DNA damaging agents and illustrate a molecular pathway whereby chronic exposure to a bacterial toxin may promote genomic instability.

Host-defense and trefoil factor family peptides in skin secretions of the Mawa clawed frog Xenopus boumbaensis (Pipidae).

Science.gov (United States)

Conlon, J Michael; Mechkarska, Milena; Kolodziejek, Jolanta; Leprince, Jérôme; Coquet, Laurent; Jouenne, Thierry; Vaudry, Hubert; Nowotny, Norbert; King, Jay D

2015-10-01

Peptidomic analysis of norepinephrine-stimulated skin secretions from the octoploid Mawa clawed frog Xenopus boumbaensis Loumont, 1983 led to the identification and characterization of 15 host-defense peptides belonging to the magainin (two peptides), peptide glycine-leucine-amide (PGLa; three peptides), xenopsin precursor fragment (XPF; three peptides), caerulein precursor fragment (CPF; two peptides), and caerulein precursor fragment-related peptide (CPF-RP; five peptides) families. In addition, caerulein and three peptides with structural similarity to the trefoil factor family (TFF) peptides, xP2 and xP4 from Xenopus laevis were also present in the secretions. Consistent with data from comparisons of the nucleotides sequence of mitochondrial and nuclear genes, the primary structures of the peptides suggest a close phylogenetic relationship between X. boumbaensis and the octoploid frogs Xenopus amieti and Xenopus andrei. As the three species occupy disjunct ranges within Cameroon, it is suggested that they diverged from a common ancestor by allopatric speciation. Copyright © 2015 Elsevier Inc. All rights reserved.

Structural basis for antagonizing a host restriction factor by C7 family of poxvirus host-range proteins

OpenAIRE

Meng, Xiangzhi; Krumm, Brian; Li, Yongchao; Deng, Junpeng; Xiang, Yan

2015-01-01

Productive viral replication requires overcoming many barriers posed by the host innate immune system. Human sterile alpha motif domain-containing 9 (SAMD9) is a newly identified antiviral factor that is specifically targeted by poxvirus proteins belonging to the C7 family of host-range factors. Here we provide the first, to our knowledge, atomic view of two functionally divergent proteins from the C7 family and determine the molecular basis that dictates whether they can target SAMD9 effecti...

Exchange mechanisms for $\\pi^{-}p\\rightarrow\\rho^{0}$n and $\\rho-\\omega$ interference

CERN Document Server

Estabrooks, P G; Michael, C

1974-01-01

The 17 GeV/c pi /sup -/p to rho /sup 0/n production amplitudes are decomposed into pi , A/sub 2/ and non-evasive exchange contributions. Independent support for this description comes from the observed rho - omega interference effects and from the energy dependence of rho /sup 0/ production data. (18 refs).

Rac and Rho GTPases in cancer cell motility control

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Parri Matteo

2010-09-01

Full Text Available Abstract Rho GTPases represent a family of small GTP-binding proteins involved in cell cytoskeleton organization, migration, transcription, and proliferation. A common theme of these processes is a dynamic reorganization of actin cytoskeleton which has now emerged as a major switch control mainly carried out by Rho and Rac GTPase subfamilies, playing an acknowledged role in adaptation of cell motility to the microenvironment. Cells exhibit three distinct modes of migration when invading the 3 D environment. Collective motility leads to movement of cohorts of cells which maintain the adherens junctions and move by photolytic degradation of matrix barriers. Single cell mesenchymal-type movement is characterized by an elongated cellular shape and again requires extracellular proteolysis and integrin engagement. In addition it depends on Rac1-mediated cell polarization and lamellipodia formation. Conversely, in amoeboid movement cells have a rounded morphology, the movement is independent from proteases but requires high Rho GTPase to drive elevated levels of actomyosin contractility. These two modes of cell movement are interconvertible and several moving cells, including tumor cells, show an high degree of plasticity in motility styles shifting ad hoc between mesenchymal or amoeboid movements. This review will focus on the role of Rac and Rho small GTPases in cell motility and in the complex relationship driving the reciprocal control between Rac and Rho granting for the opportunistic motile behaviour of aggressive cancer cells. In addition we analyse the role of these GTPases in cancer progression and metastatic dissemination.

The TAM-family receptor Mer mediates production of HGF through the RhoA-dependent pathway in response to apoptotic cells.

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Park, Hyun-Jung; Baen, Ji-Yeon; Lee, Ye-Ji; Choi, Youn-Hee; Kang, Jihee Lee

2012-08-01

The TAM receptor protein tyrosine kinases Tyro3, Axl, and Mer play important roles in macrophage function. We investigated the roles of the TAM receptors in mediating the induction of hepatocyte growth factor (HGF) during the interaction of macrophages with apoptotic cells. Mer-specific neutralizing antibody, small interfering RNA (siRNA), and a recombinant Mer protein (Mer/Fc) inhibited HGF mRNA and protein expression, as well as activation of RhoA, Akt, and specific mitogen-activated protein (MAP) kinases in response to apoptotic cells. Inhibition of Axl or Tyro3 with specific antibodies, siRNA, or Fc-fusion proteins did not prevent apoptotic cell-induced HGF mRNA and protein expression and did not inhibit activation of the postreceptor signaling molecules RhoA and certain MAP kinases, including extracellular signal-regulated protein kinase and c-Jun NH(2)-terminal kinase. However, Axl- and Tyro3-specific blockers did inhibit the activation of Akt and p38 MAP kinase in response to apoptotic cells. In addition, none of the TAM receptors mediated the effects of apoptotic cells on transforming growth factor-β or epidermal growth factor mRNA expression. However, they were involved in the induction of vascular endothelial growth factor mRNA expression. Our data provide evidence that when macrophages interact with apoptotic cells, only Mer of the TAM-family receptors is responsible for mediating transcriptional HGF production through a RhoA-dependent pathway.

Membrane depolarization-induced RhoA/Rho-associated kinase activation and sustained contraction of rat caudal arterial smooth muscle involves genistein-sensitive tyrosine phosphorylation

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Mita, Mitsuo; Tanaka, Hitoshi; Yanagihara, Hayato; Nakagawa, Jun-ichi; Hishinuma, Shigeru; Sutherland, Cindy; Walsh, Michael P.; Shoji, Masaru

2013-01-01

Rho-associated kinase (ROK) activation plays an important role in K+-induced contraction of rat caudal arterial smooth muscle (Mita et al., Biochem J. 2002; 364: 431–40). The present study investigated a potential role for tyrosine kinase activity in K+-induced RhoA activation and contraction. The non-selective tyrosine kinase inhibitor genistein, but not the src family tyrosine kinase inhibitor PP2, inhibited K+-induced sustained contraction (IC50 = 11.3 ± 2.4 µM). Genistein (10 µM) inhibited the K+-induced increase in myosin light chain (LC20) phosphorylation without affecting the Ca2+ transient. The tyrosine phosphatase inhibitor vanadate induced contraction that was reversed by genistein (IC50 = 6.5 ± 2.3 µM) and the ROK inhibitor Y-27632 (IC50 = 0.27 ± 0.04 µM). Vanadate also increased LC20 phosphorylation in a genistein- and Y-27632-dependent manner. K+ stimulation induced translocation of RhoA to the membrane, which was inhibited by genistein. Phosphorylation of MYPT1 (myosin-targeting subunit of myosin light chain phosphatase) was significantly increased at Thr855 and Thr697 by K+ stimulation in a genistein- and Y-27632-sensitive manner. Finally, K+ stimulation induced genistein-sensitive tyrosine phosphorylation of proteins of ∼55, 70 and 113 kDa. We conclude that a genistein-sensitive tyrosine kinase, activated by the membrane depolarization-induced increase in [Ca2+]i, is involved in the RhoA/ROK activation and sustained contraction induced by K+. Ca2+ sensitization, myosin light chain phosphatase, RhoA, Rho-associated kinase, tyrosine kinase PMID:24133693

Exploring Conditions to Enhance Student/Host Family Interaction Abroad

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Knight, Susan M.; Schmidt-Rinehart, Barbara C.

2010-01-01

This study investigates the role of task-based learning in the study abroad experience in order to enhance interaction with the host family. Tasks were incorporated into a Family Interaction Journal and implemented under four evolving, though different, conditions over a 5-year period. The conditions were: (1) home campus administered/student…

Structural basis for antagonizing a host restriction factor by C7 family of poxvirus host-range proteins.

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Meng, Xiangzhi; Krumm, Brian; Li, Yongchao; Deng, Junpeng; Xiang, Yan

2015-12-01

Human sterile alpha motif domain-containing 9 (SAMD9) protein is a host restriction factor for poxviruses, but it can be overcome by some poxvirus host-range proteins that share homology with vaccinia virus C7 protein. To understand the mechanism of action for this important family of host-range factors, we determined the crystal structures of C7 and myxoma virus M64, a C7 family member that is unable to antagonize SAMD9. Despite their different functions and only 23% sequence identity, the two proteins have very similar overall structures, displaying a previously unidentified fold comprised of a compact 12-stranded antiparallel β-sandwich wrapped in two short α helices. Extensive structure-guided mutagenesis of C7 identified three loops clustered on one edge of the β sandwich as critical for viral replication and binding with SAMD9. The loops are characterized with functionally important negatively charged, positively charged, and hydrophobic residues, respectively, together forming a unique "three-fingered molecular claw." The key residues of the claw are not conserved in two C7 family members that do not antagonize SAMD9 but are conserved in distantly related C7 family members from four poxvirus genera that infect diverse mammalian species. Indeed, we found that all in the latter group of proteins bind SAMD9. Taken together, our data indicate that diverse mammalian poxviruses use a conserved molecular claw in a C7-like protein to target SAMD9 and overcome host restriction.

Nanofibrillar scaffolds induce preferential activation of Rho GTPases in cerebral cortical astrocytes

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Tiryaki, Volkan Mujdat; Ayres, Virginia M; Khan, Adeel A; Ahmed, Ijaz; Shreiber, David I; Meiners, Sally

2012-01-01

Cerebral cortical astrocyte responses to polyamide nanofibrillar scaffolds versus poly-L-lysine (PLL)-functionalized planar glass, unfunctionalized planar Aclar coverslips, and PLL-functionalized planar Aclar surfaces were investigated by atomic force microscopy and immunocytochemistry. The physical properties of the cell culture environments were evaluated using contact angle and surface roughness measurements and compared. Astrocyte morphological responses, including filopodia, lamellipodia, and stress fiber formation, and stellation were imaged using atomic force microscopy and phalloidin staining for F-actin. Activation of the corresponding Rho GTPase regulators was investigated using immunolabeling with Cdc42, Rac1, and RhoA. Astrocytes cultured on the nanofibrillar scaffolds showed a unique response that included stellation, cell–cell interactions by stellate processes, and evidence of depression of RhoA. The results support the hypothesis that the extracellular environment can trigger preferential activation of members of the Rho GTPase family, with demonstrable morphological consequences for cerebral cortical astrocytes. PMID:22915841

QCD factorizations in {gamma}*{gamma}*->{rho}{sub L}{sup 0}{rho}{sub L}{sup 0}

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Pire, B. [CPHT, Unite mixte 7644 du CNRS, Ecole Polytechnique, 91128 Palaiseau (France)]. E-mail: pire@cpht.polytechnique.fr; Segond, M. [LPT, Unite mixte 8627 du CNRS, Universite Paris-Sud, 91405 Orsay (France); Szymanowski, L. [LPT, Unite mixte 8627 du CNRS, Universite Paris-Sud, 91405 Orsay (France); Universite de Liege, B-4000 Liege (Belgium); Soltan Institute for Nuclear Studies, Hoza 69, 00-681 Warsaw (Poland); Wallon, S. [LPT, Unite mixte 8627 du CNRS. , Universite Paris-Sud, 91405 Orsay (France)

2006-08-24

We calculate the lowest order QCD amplitude, i.e. the quark exchange contribution, to the forward production amplitude of a pair of longitudinally polarized {rho} mesons in the scattering of two virtual photons {gamma}*(Q{sub 1}){gamma}*(Q{sub 2})->{rho}{sub L}{sup 0}{rho}{sub L}{sup 0}. We show that the scattering amplitude simultaneously factorizes in two quite different ways: the part with transverse photons is described by the QCD factorization formula involving the generalized distribution amplitude of two final {rho} mesons, whereas the part with longitudinally polarized photons takes the QCD factorized form with the {gamma}{sub L}*->{rho}{sub L}{sup 0} transition distribution amplitude. Perturbative expressions for these, in general, non-perturbative functions are obtained in terms of the {rho}-meson distribution amplitude.

Multilocus Sequence Analysis of Cercospora spp. from Different Host Plant Families

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Floreta Fiska Yuliarni

2014-06-01

Full Text Available Identification of the genus Cercospora is still complicated due to the host preferences often being used as the main criteria to propose a new name. We determined the relationship between host plants and multilocus sequence variations (ITS rDNA including 5.8S rDNA, elongation factor 1-α, and calmodulin in Cercospora spp. to investigate the host specificity. We used 53 strains of Cercospora spp. infecting 12 plant families for phylogenetic analysis. The sequences of 23 strains of Cercospora spp. infecting the plant families of Asteraceae, Cucurbitaceae, and Solanaceae were determined in this study. The sequences of 30 strains of Cercospora spp. infecting the plant families of Fabaceae, Amaranthaceae, Apiaceae, Plumbaginaceae, Malvaceae, Cistaceae, Plantaginaceae, Lamiaceae, and Poaceae were obtained from GenBank. The molecular phylogenetic analysis revealed that the majority of Cercospora species lack host specificity, and only C. zinniicola, C. zeina, C. zeae-maydis, C. cocciniae, and C. mikaniicola were found to be host-specific. Closely related species of Cercospora could not be distinguished using molecular analyses of ITS, EF, and CAL gene regions. The topology of the phylogenetic tree based on the CAL gene showed a better topology and Cercospora species separation than the trees developed based on the ITS rDNA region or the EF gene.

Rho GTPase expression in human myeloid cells.

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Suzanne F G van Helden

Full Text Available Myeloid cells are critical for innate immunity and the initiation of adaptive immunity. Strict regulation of the adhesive and migratory behavior is essential for proper functioning of these cells. Rho GTPases are important regulators of adhesion and migration; however, it is unknown which Rho GTPases are expressed in different myeloid cells. Here, we use a qPCR-based approach to investigate Rho GTPase expression in myeloid cells.We found that the mRNAs encoding Cdc42, RhoQ, Rac1, Rac2, RhoA and RhoC are the most abundant. In addition, RhoG, RhoB, RhoF and RhoV are expressed at low levels or only in specific cell types. More differentiated cells along the monocyte-lineage display lower levels of Cdc42 and RhoV, while RhoC mRNA is more abundant. In addition, the Rho GTPase expression profile changes during dendritic cell maturation with Rac1 being upregulated and Rac2 downregulated. Finally, GM-CSF stimulation, during macrophage and osteoclast differentiation, leads to high expression of Rac2, while M-CSF induces high levels of RhoA, showing that these cytokines induce a distinct pattern. Our data uncover cell type specific modulation of the Rho GTPase expression profile in hematopoietic stem cells and in more differentiated cells of the myeloid lineage.

Identification and characterization of a lymphocytic Rho-GTPase effector: rhotekin-2

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Collier, F.M.; Gregorio-King, C.C.; Gough, T.J.; Talbot, C.D.; Walder, K.; Kirkland, M.A.

2004-01-01

Rhotekin belongs to the group of proteins containing a Rho-binding domain that are target peptides (effectors) for the Rho-GTPases. We previously identified a novel cDNA with homology to human rhotekin and in this study we cloned and characterized the coding region of this novel 12-exon gene. The ORF encodes a 609 amino-acid protein comprising a Class I Rho-binding domain and pleckstrin homology (PH) domain. Cellular cDNA expression of this new protein, designated Rhotekin-2 (RTKN2), was shown in the cytosol and nucleus of CHO cells. Using bioinformatics and RTPCR we identified three major splice variants, which vary in both the Rho-binding and PH domains. Real-time PCR studies showed exclusive RTKN2 expression in pooled lymphocytes and further purification indicated sole expression in CD4 pos T-cells and bone marrow-derived B-cells. Gene expression was increased in quiescent T-cells but negligible in activated proliferating cells. In malignant samples expression was absent in myeloid leukaemias, low in most B-cell malignancies and CD8 pos T-cell malignancies, but very high in CD4 pos /CD8 pos T-lymphoblastic lymphoma. As the Rho family is critical in lymphocyte development and function, RTKN2 may play an important role in lymphopoiesis

The atypical structure and function of newborn arterial endothelium is mediated by Rho/Rho kinase signaling.

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Flavahan, Sheila; Flavahan, Nicholas A

2014-08-15

Endothelium of fetal or newborn arteries is atypical, displaying actin stress fibers and reduced nitric oxide (NO)-mediated dilatation. This study tested the hypothesis that Rho/Rho kinase signaling, which promotes endothelial stress fibers and inhibits endothelial dilatation, contributed to this phenotype. Carotid arteries were isolated from newborn [postnatal day 1 (P1)], P7, and P21 mice. Endothelial dilatation to acetylcholine (pressure myograph) was minimal at P1, increased at P7, and further increased at P21. Inhibition of Rho (C3 transferase) or Rho kinase (Y27632, fasudil) significantly increased dilatation to acetylcholine in P1 arteries but had no effect in P7 or P21 arteries. After inhibition of NO synthase (N(G)-nitro-l-arginine methyl ester), Rho kinase inhibition no longer increased acetylcholine responses in P1 arteries. Rho kinase inhibition did not affect dilatation to the NO donor DEA-NONOate. The endothelial actin cytoskeleton was labeled with phalloidin and visualized by laser-scanning microscopy. In P1 arteries, the endothelium had prominent transcytoplasmic stress fibers, whereas in P7 and P21 arteries, the actin fibers had a significantly reduced intensity and were restricted to cell borders. Phosphorylation of myosin light chains, a Rho kinase substrate, was highest in P1 endothelium and significantly reduced in P7 and P21 endothelium (laser-scanning microscopy). In P1 arteries, inhibition of Rho (C3 transferase) or Rho kinase (Y27632) significantly reduced the intensity of actin fibers, which were restricted to cell borders. Similarly, in P1 arteries, Rho inhibition significantly reduced endothelial levels of phosphorylated myosin light chains. These results indicate that the atypical function and morphology of newborn endothelium is mediated by Rho/Rho kinase signaling. Copyright © 2014 the American Physiological Society.

RhoE deficiency produces postnatal lethality, profound motor deficits and neurodevelopmental delay in mice.

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Enric Mocholí

Full Text Available Rnd proteins are a subfamily of Rho GTPases involved in the control of actin cytoskeleton dynamics and other cell functions such as motility, proliferation and survival. Unlike other members of the Rho family, Rnd proteins lack GTPase activity and therefore remain constitutively active. We have recently described that RhoE/Rnd3 is expressed in the Central Nervous System and that it has a role in promoting neurite formation. Despite their possible relevance during development, the role of Rnd proteins in vivo is not known. To get insight into the in vivo function of RhoE we have generated mice lacking RhoE expression by an exon trapping cassette. RhoE null mice (RhoE gt/gt are smaller at birth, display growth retardation and early postnatal death since only half of RhoE gt/gt mice survive beyond postnatal day (PD 15 and 100% are dead by PD 29. RhoE gt/gt mice show an abnormal body position with profound motor impairment and impaired performance in most neurobehavioral tests. Null mutant mice are hypoactive, show an immature locomotor pattern and display a significant delay in the appearance of the hindlimb mature responses. Moreover, they perform worse than the control littermates in the wire suspension, vertical climbing and clinging, righting reflex and negative geotaxis tests. Also, RhoE ablation results in a delay of neuromuscular maturation and in a reduction in the number of spinal motor neurons. Finally, RhoE gt/gt mice lack the common peroneal nerve and, consequently, show a complete atrophy of the target muscles. This is the first model to study the in vivo functions of a member of the Rnd subfamily of proteins, revealing the important role of Rnd3/RhoE in the normal development and suggesting the possible involvement of this protein in neurological disorders.

RhoA-Mediated Functions in C3H10T1/2 Osteoprogenitors Are Substrate Topography Dependent.

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Ogino, Yoichiro; Liang, Ruiwei; Mendonça, Daniela B S; Mendonça, Gustavo; Nagasawa, Masako; Koyano, Kiyoshi; Cooper, Lyndon F

2016-03-01

Surface topography broadly influences cellular responses. Adherent cell activities are regulated, in part, by RhoA, a member of the Rho-family of GTPases. In this study, we evaluated the influence of surface topography on RhoA activity and associated cellular functions. The murine mesenchymal stem cell line C3H10T1/2 cells (osteoprogenitor cells) were cultured on titanium substrates with smooth topography (S), microtopography (M), and nanotopography (N) to evaluate the effect of surface topography on RhoA-mediated functions (cell spreading, adhesion, migration, and osteogenic differentiation). The influence of RhoA activity in the context of surface topography was also elucidated using RhoA pharmacologic inhibitor. Following adhesion, M and N adherent cells developed multiple projections, while S adherent cells had flattened and widespread morphology. RhoA inhibitor induced remarkable longer and thinner cytoplasmic projections on all surfaces. Cell adhesion and osteogenic differentiation was topography dependent with S topography roughness dependent (S topography. Smooth surface adherent cells appear highly sensitive to RhoA function, while nano-scale topography adherent cell may utilize alternative cellular signaling pathway(s) to influence adherent cellular functions regardless of RhoA activity. © 2015 Wiley Periodicals, Inc.

A negative modulatory role for rho and rho-associated kinase signaling in delamination of neural crest cells

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Kalcheim Chaya

2008-10-01

Full Text Available Abstract Background Neural crest progenitors arise as epithelial cells and then undergo a process of epithelial to mesenchymal transition that precedes the generation of cellular motility and subsequent migration. We aim at understanding the underlying molecular network. Along this line, possible roles of Rho GTPases that act as molecular switches to control a variety of signal transduction pathways remain virtually unexplored, as are putative interactions between Rho proteins and additional known components of this cascade. Results We investigated the role of Rho/Rock signaling in neural crest delamination. Active RhoA and RhoB are expressed in the membrane of epithelial progenitors and are downregulated upon delamination. In vivo loss-of-function of RhoA or RhoB or of overall Rho signaling by C3 transferase enhanced and/or triggered premature crest delamination yet had no effect on cell specification. Consistently, treatment of explanted neural primordia with membrane-permeable C3 or with the Rock inhibitor Y27632 both accelerated and enhanced crest emigration without affecting cell proliferation. These treatments altered neural crest morphology by reducing stress fibers, focal adhesions and downregulating membrane-bound N-cadherin. Reciprocally, activation of endogenous Rho by lysophosphatidic acid inhibited emigration while enhancing the above. Since delamination is triggered by BMP and requires G1/S transition, we examined their relationship with Rho. Blocking Rho/Rock function rescued crest emigration upon treatment with noggin or with the G1/S inhibitor mimosine. In the latter condition, cells emigrated while arrested at G1. Conversely, BMP4 was unable to rescue cell emigration when endogenous Rho activity was enhanced by lysophosphatidic acid. Conclusion Rho-GTPases, through Rock, act downstream of BMP and of G1/S transition to negatively regulate crest delamination by modifying cytoskeleton assembly and intercellular adhesion.

Rho GTPasas como blancos terapéuticos relevantes en cáncer y otras enfermedades humanas Rho GTPases as therapeutic targets in cancer and other human diseases

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Pablo Lorenzano Menna

2010-12-01

Full Text Available Las Rho GTPasas son una familia de proteínas clave en la transmisión de señales provenientes del exterior celular hacia efectores intracelulares tanto citoplasmáticos como nucleares. En los últimos año ha habido un desarrollo vertiginoso de múltiples herramientas genéticas y farmacológicas, lo que ha permitido establecer de manera mucho más precisa las funciones específicas de estas proteínas. El objetivo de la presente revisión es hacer foco en las múltiples funciones celulares reguladas por las Rho GTPasas, describiendo en detalle el mecanismo molecular involucrado. Se discute además la participación de estas proteínas en diversas enfermedades humanas haciendo énfasis en su vinculación con el cáncer. Por último, se hace una actualización detallada sobre las estrategias terapéuticas en experimentación que tienen a las Rho GTPasas como blancos moleculares.Rho GTPases are a key protein family controlling the transduction of external signals to cytoplasmatic and nuclear effectors. In the last few years, the development of genetic and pharmacological tools has allowed a more precise definition of the specific roles of Rho GTPases. The aim of this review is to describe the cellular functions regulated by these proteins with focus on the molecular mechanism involved. We also address the role of Rho GTPases in the development of different human diseases such as cancer. Finally, we describe different experimental therapeutic strategies with Rho GTPases as molecular targets.

DMPD: The interferon regulatory factor family in host defense: mechanism of action. [Dynamic Macrophage Pathway CSML Database

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Full Text Available 17502370 The interferon regulatory factor family in host defense: mechanism of acti....html) (.csml) Show The interferon regulatory factor family in host defense: mechanism of action. PubmedID 1...7502370 Title The interferon regulatory factor family in host defense: mechanism

Rho GTPase function in tumorigenesis

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Karlsson, R; Pedersen, Esben Ditlev Kølle; Wang, Zhipeng

2009-01-01

, for that reason, Rho GTPases, their regulators, and their effectors have been suggested to control tumor formation and progression in humans. However, while the tumor-relevant functions of Rho GTPases are very well documented in vitro, we are only now beginning to assess their contribution to cancer in human...... patients and in animal models. This review will give a very brief overview of Rho GTPase function in general and then focus on in vivo evidence for a role of Rho GTPases in malignant tumors, both in human patients and in genetically modified mice....

Ornithine decarboxylase regulates the activity and localization of rhoA via polyamination

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Maekitie, Laura T.; Kanerva, Kristiina; Andersson, Leif C.

2009-01-01

Ornithine decarboxylase (ODC) is the rate-limiting enzyme of polyamine synthesis. Polyamines and ODC are connected to cell proliferation and transformation. Resting cells display a low ODC activity while normal, proliferating cells display fluctuations in ODC activity that coincide with changes in the actin cytoskeleton during the cell cycle. Cancerous cells display constitutively elevated ODC activity. Overexpression of ODC in NIH 3T3 fibroblasts induces a transformed phenotype. The cytoskeletal rearrangements during cytokinesis and cell transformation are intimately coupled to the ODC activity but the molecular mechanisms have remained elusive. In this study we investigated how ODC and polyamines influence the organization of the cytoskeleton. Given that the small G-proteins of the rho family are key modulators of the actin cytoskeleton, we investigated the molecular interactions of rhoA with ODC and polyamines. Our results show that transglutaminase-catalyzed polyamination of rhoA regulates its activity. The polyamination status of rhoA crucially influences the progress of the cell cycle as well as the rate of transformation of rat fibroblasts infected with temperature-sensitive v-src. We also show that ODC influences the intracellular distribution of rhoA. These findings provide novel insights into the mechanisms by which ODC and polyamines regulate the dynamics of the cytoskeleton during cell proliferation and transformation

A Bacterial Pathogen Targets a Host Rab-Family GTPase Defense Pathway with a GAP.

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Spanò, Stefania; Gao, Xiang; Hannemann, Sebastian; Lara-Tejero, María; Galán, Jorge E

2016-02-10

Cell-autonomous defense mechanisms are potent strategies that protect individual cells against intracellular pathogens. The Rab-family GTPase Rab32 was previously shown to restrict the intracellular human pathogen Salmonella Typhi, but its potential broader role in antimicrobial defense remains unknown. We show that Rab32 represents a general cell-autonomous, antimicrobial defense that is counteracted by two Salmonella effectors. Mice lacking Rab-32 or its nucleotide exchange factor BLOC-3 are permissive to S. Typhi infection and exhibit increased susceptibility to S. Typhimurium. S. Typhimurium counters this defense pathway by delivering two type III secretion effectors, SopD2, a Rab32 GAP, and GtgE, a specific Rab32 protease. An S. Typhimurium mutant strain lacking these two effectors exhibits markedly reduced virulence, which is fully restored in BLOC-3-deficient mice. These results demonstrate that a cell-autonomous, Rab32-dependent host defense pathway plays a central role in the defense against vacuolar pathogens and describe a mechanism evolved by a bacterial pathogen to counter it. Copyright © 2016 Elsevier Inc. All rights reserved.

Measurement of Exclusive $\\rho^{0}\\rho^{0}$ Production in Mid-Virtuality Two-Photon Interactions at LEP

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Achard, P.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M.G.; Anderhub, H.; Andreev, Valery P.; Anselmo, F.; Arefev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay, L.; Baldew, S.V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillere, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B.L.; Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J.J.; Blyth, S.C.; Bobbink, G.J.; Bohm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J.G.; Brochu, F.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Chamizo, M.; Chang, Y.H.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G.M.; Chen, H.F.; Chen, H.S.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; de la Cruz, B.; Cucciarelli, S.; de Asmundis, R.; Deglon, P.; Debreczeni, J.; Degre, A.; Dehmelt, K.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M.T.; Duchesneau, D.; Duda, M.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.; Engler, A.; Eppling, F.J.; Extermann, P.; Falagan, M.A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fesefeldt, H.; Fiandrini, E.; Field, J.H.; Filthaut, F.; Fisher, P.H.; Fisher, W.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Iouri; Ganguli, S.N.; Garcia-Abia, Pablo; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z.F.; Grenier, Gerald Jean; Grimm, O.; Gruenewald, M.W.; Guida, M.; Gupta, V.K.; Gurtu, A.; Gutay, L.J.; Haas, D.; Hatzifotiadou, D.; Hebbeker, T.; Herve, Alain; Hirschfelder, J.; Hofer, H.; Hohlmann, M.; Holzner, G.; Hou, S.R.; Jin, B.N.; Jindal, P.; Jones, Lawrence W.; de Jong, P.; Josa-Mutuberria, I.; Kaur, M.; Kienzle-Focacci, M.N.; Kim, J.K.; Kirkby, Jasper; Kittel, W.; Klimentov, A.; Konig, A.C.; Kopal, M.; Koutsenko, V.; Kraber, M.; Kraemer, R.W.; Kruger, A.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Le Goff, J.M.; Leiste, R.; Levtchenko, M.; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C.H.; Lin, W.T.; Linde, F.L.; Lista, L.; Liu, Z.A.; Lohmann, W.; Longo, E.; Lu, Y.S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W.G.; Malgeri, L.; Malinin, A.; Mana, C.; Mans, J.; Martin, J.P.; Marzano, F.; Mazumdar, K.; McNeil, R.R.; Mele, S.; Merola, L.; Meschini, M.; Metzger, W.J.; Mihul, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G.B.; Muanza, G.S.; Muijs, A.J.M.; Musicar, B.; Musy, M.; Nagy, S.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Kluge, Hannelies; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.; Passaleva, G.; Patricelli, S.; Paul, Thomas Cantzon; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Piccolo, D.; Pierella, F.; Pioppi, M.; Piroue, P.A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofev, D.; Quartieri, J.; Rahal-Callot, G.; Rahaman, Mohammad Azizur; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P.G.; Ranieri, R.; Raspereza, A.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Riemann, S.; Riles, Keith; Roe, B.P.; Romero, L.; Rosca, A.; Rosemann, C.; Rosenbleck, C.; Rosier-Lees, S.; Roth, Stefan; Rubio, J.A.; Ruggiero, G.; Rykaczewski, H.; Sakharov, A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schafer, C.; Schegelsky, V.; Schopper, H.; Schotanus, D.J.; Sciacca, C.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.; Steuer, M.; Stickland, D.P.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L.Z.; Sushkov, S.; Suter, H.; Swain, J.D.; Szillasi, Z.; Tang, X.W.; Tarjan, P.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, Charles; Ting, Samuel C.C.; Ting, S.M.; Tonwar, S.C.; Toth, J.; Tully, C.; Tung, K.L.; Ulbricht, J.; Valente, E.; Van de Walle, R.T.; Vasquez, R.; Veszpremi, V.; Vesztergombi, G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobev, I.; Vorobyov, A.A.; Wadhwa, M.; Wang, Q.; Wang, X.L.; Wang, Z.M.; Weber, M.; Wynhoff, S.; Xia, L.; Xu, Z.Z.; Yamamoto, J.; Yang, B.Z.; Yang, C.G.; Yang, H.J.; Yang, M.; Yeh, S.C.; Zalite, An.; Zalite, Yu.; Zhang, Z.P.; Zhao, J.; Zhu, G.Y.; Zhu, R.Y.; Zhuang, H.L.; Zichichi, A.; Zimmermann, B.; Zoller, M.

2004-01-01

Exclusive rho^0 rho^0 production in two-photon collisions between a quasi-real and a mid-virtuality photon is studied with data collected at LEP at centre-of-mass energies 183GeV rho^0 rho^0 is determined as a function of the photon virtuality, q^2, and the two-photon centre-of-mass energy, Wgg, in the kinematic region: 0.2GeV^2 < q^2 < 0.85GeV^2 and 1.1GeV < Wgg < 3GeV.

Viral activation of MK2-hsp27-p115RhoGEF-RhoA signaling axis causes cytoskeletal rearrangements, p-body disruption and ARE-mRNA stabilization.

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Jennifer A Corcoran

2015-01-01

Full Text Available Kaposi's sarcoma-associated herpesvirus (KSHV is the infectious cause of several AIDS-related cancers, including the endothelial cell (EC neoplasm Kaposi's sarcoma (KS. KSHV-infected ECs secrete abundant host-derived pro-inflammatory molecules and angiogenic factors that contribute to tumorigenesis. The precise contributions of viral gene products to this secretory phenotype remain to be elucidated, but there is emerging evidence for post-transcriptional regulation. The Kaposin B (KapB protein is thought to contribute to the secretory phenotype in infected cells by binding and activating the stress-responsive kinase MK2, thereby selectively blocking decay of AU-rich mRNAs (ARE-mRNAs encoding pro-inflammatory cytokines and angiogenic factors. Processing bodies (PBs are cytoplasmic ribonucleoprotein foci in which ARE-mRNAs normally undergo rapid 5' to 3' decay. Here, we demonstrate that PB dispersion is a feature of latent KSHV infection, which is dependent on kaposin protein expression. KapB is sufficient to disperse PBs, and KapB-mediated ARE-mRNA stabilization could be partially reversed by treatments that restore PBs. Using a combination of genetic and chemical approaches we provide evidence that KapB-mediated PB dispersion is dependent on activation of a non-canonical Rho-GTPase signaling axis involving MK2, hsp27, p115RhoGEF and RhoA. PB dispersion in latently infected cells is likewise dependent on p115RhoGEF. In addition to PB dispersion, KapB-mediated RhoA activation in primary ECs caused actin stress fiber formation, increased cell motility and angiogenesis; these effects were dependent on the activity of the RhoA substrate kinases ROCK1/2. By contrast, KapB-mediated PB dispersion occurred in a ROCK1/2-independent manner. Taken together, these observations position KapB as a key contributor to viral reprogramming of ECs, capable of eliciting many of the phenotypes characteristic of KS tumor cells, and strongly contributing to the post

Insight into pattern of codon biasness and nucleotide base usage in serotonin receptor gene family from different mammalian species.

Science.gov (United States)

Dass, J Febin Prabhu; Sudandiradoss, C

2012-07-15

5-HT (5-Hydroxy-tryptamine) or serotonin receptors are found both in central and peripheral nervous system as well as in non-neuronal tissues. In the animal and human nervous system, serotonin produces various functional effects through a variety of membrane bound receptors. In this study, we focus on 5-HT receptor family from different mammals and examined the factors that account for codon and nucleotide usage variation. A total of 110 homologous coding sequences from 11 different mammalian species were analyzed using relative synonymous codon usage (RSCU), correspondence analysis (COA) and hierarchical cluster analysis together with nucleotide base usage frequency of chemically similar amino acid codons. The mean effective number of codon (ENc) value of 37.06 for 5-HT(6) shows very high codon bias within the family and may be due to high selective translational efficiency. The COA and Spearman's rank correlation reveals that the nucleotide compositional mutation bias as the major factors influencing the codon usage in serotonin receptor genes. The hierarchical cluster analysis suggests that gene function is another dominant factor that affects the codon usage bias, while species is a minor factor. Nucleotide base usage was reported using Goldman, Engelman, Stietz (GES) scale reveals the presence of high uracil (>45%) content at functionally important hydrophobic regions. Our in silico approach will certainly help for further investigations on critical inference on evolution, structure, function and gene expression aspects of 5-HT receptors family which are potential antipsychotic drug targets. Copyright © 2012 Elsevier B.V. All rights reserved.

Overexpression of GEFT, a Rho family guanine nucleotide exchange factor, predicts poor prognosis in patients with rhabdomyosarcoma.

Science.gov (United States)

Sun, Chao; Liu, Chunxia; Li, Shugang; Li, Hongan; Wang, Yuanyuan; Xie, Yuwen; Li, Bingcheng; Cui, Xiaobin; Chen, Yunzhao; Zhang, Wenjie; Li, Feng

2014-01-01

Rhabdomyosarcoma (RMS) is one of the most common soft-tissue sarcomas in children and adolescents with poor prognosis. Yet, there is lack of effective prognostic biomarkers for RMS. The present study, therefore, aimed to explore potential biomarkers for RMS based on our previous findings using array comparative genomic hybridization. We investigated guanine nucleotide exchange factor, GEFT, at expression level in 45 RMS patients and 36 normal striated muscle controls using immunohistochemistry using tissue microarrays. The expression rate of GEFT in RMS samples (42/45, 93.33%) was significantly higher (Prate of GEFT in RMS (31/45, 68.89%) was also significantly higher (P<0.05) than that in normal controls (0/36, 0.00%). Increased expression of GEFT correlated significantly with advanced disease stages (stages III/IV) (P=0.001), lymph node metastasis (P=0.019), and distant metastasis (P=0.004), respectively, in RMS patients. In addition, RMS patients having overexpressed GEFT experienced worse overall survival (OS) than those having low levels of GEFT (P=0.001). GEFT overexpression was determined to be an independent prognostic factor for poor OS in RMS patients (hazard ratio: 3.491, 95% confidence interval: 1.121-10.871, P=0.004). In conclusion, these observations provide the first evidence of GEFT overexpression in RMS and its correlations with disease aggressiveness and metastasis. These findings suggest that GEFT may serve as a promising biomarker predicting poor prognosis in RMS patients, thus implying its potential as a therapeutic target.

p115 RhoGEF activates the Rac1 GTPase signaling cascade in MCP1 chemokine-induced vascular smooth muscle cell migration and proliferation.

Science.gov (United States)

Singh, Nikhlesh K; Janjanam, Jagadeesh; Rao, Gadiparthi N

2017-08-25

Although the involvement of Rho proteins in the pathogenesis of vascular diseases is well studied, little is known about the role of their upstream regulators, the Rho guanine nucleotide exchange factors (RhoGEFs). Here, we sought to identify the RhoGEFs involved in monocyte chemotactic protein 1 (MCP1)-induced vascular wall remodeling. We found that, among the RhoGEFs tested, MCP1 induced tyrosine phosphorylation of p115 RhoGEF but not of PDZ RhoGEF or leukemia-associated RhoGEF in human aortic smooth muscle cells (HASMCs). Moreover, p115 RhoGEF inhibition suppressed MCP1-induced HASMC migration and proliferation. Consistent with these observations, balloon injury (BI) induced p115 RhoGEF tyrosine phosphorylation in rat common carotid arteries, and siRNA-mediated down-regulation of its levels substantially attenuated BI-induced smooth muscle cell migration and proliferation, resulting in reduced neointima formation. Furthermore, depletion of p115 RhoGEF levels also abrogated MCP1- or BI-induced Rac1-NFATc1-cyclin D1-CDK6-PKN1-CDK4-PAK1 signaling, which, as we reported previously, is involved in vascular wall remodeling. Our findings also show that protein kinase N1 (PKN1) downstream of Rac1-cyclin D1/CDK6 and upstream of CDK4-PAK1 in the p115 RhoGEF-Rac1-NFATc1-cyclin D1-CDK6-PKN1-CDK4-PAK1 signaling axis is involved in the modulation of vascular wall remodeling. Of note, we also observed that CCR2-G i/o -Fyn signaling mediates MCP1-induced p115 RhoGEF and Rac1 GTPase activation. These findings suggest that p115 RhoGEF is critical for MCP1-induced HASMC migration and proliferation in vitro and for injury-induced neointima formation in vivo by modulating Rac1-NFATc1-cyclin D1-CDK6-PKN1-CDK4-PAK1 signaling. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Chiral symmetry breaking and the spin content of the {rho} and {rho}{sup '} mesons

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Glozman, L.Ya., E-mail: leonid.glozman@uni-graz.at [Institut fuer Physik, FB Theoretische Physik, Universitaet Graz, A-8010 Graz (Austria); Lang, C.B., E-mail: christian.lang@uni-graz.at [Institut fuer Physik, FB Theoretische Physik, Universitaet Graz, A-8010 Graz (Austria); Limmer, M., E-mail: markus.limmer@uni-graz.at [Institut fuer Physik, FB Theoretische Physik, Universitaet Graz, A-8010 Graz (Austria)

2011-11-03

Using interpolators with different SU(2){sub L}xSU(2){sub R} transformation properties we study the chiral symmetry and spin contents of the {rho} and {rho}{sup '} mesons in lattice simulations with dynamical quarks. A ratio of couplings of the q-bar {gamma}{sup i}{tau}q and q-bar {sigma}{sup 0}i{tau}q interpolators to a given meson state at different resolution scales tells one about the degree of chiral symmetry breaking in the meson wave function at these scales. Using a Gaussian gauge invariant smearing of the quark fields in the interpolators, we are able to extract the chiral content of mesons up to the infrared resolution of {approx}1 fm. In the ground state {rho} meson the chiral symmetry is strongly broken with comparable contributions of both the (0,1)+(1,0) and (1/2,1/2){sub b} chiral representations with the former being the leading contribution. In contrast, in the {rho}{sup '} meson the degree of chiral symmetry breaking is manifestly smaller and the leading representation is (1/2,1/2){sub b}. Using a unitary transformation from the chiral basis to the {sup 2S+1}L{sub J} basis, we are able to define and measure the angular momentum content of mesons in the rest frame. This definition is different from the traditional one which uses parton distributions in the infinite momentum frame. The {rho} meson is practically a {sup 3}S{sub 1} state with no obvious trace of a 'spin crisis'. The {rho}{sup '} meson has a sizeable contribution of the {sup 3}D{sub 1} wave, which implies that the {rho}{sup '} meson cannot be considered as a pure radial excitation of the {rho} meson.

Involvement of rho-gtpases in fibroblast adhesion and fibronectine fibrillogenesis under stretch

Science.gov (United States)

Guignandon, A.; Lambert, C.; Rattner, A.; Servotte, S.; Lapiere, C.; Nusgens, B.; Vico, L.

The Rho family small GTPases play a crucial role in mediating cellular adaptation to mechanical stimulation (MS), and possibly to microgravity (μg), through effects on the cytoskeleton and cell adhesion which is, in turn, mainly regulated by fibronectin fibrillogenesis (FnF). It remains unclear how mechanical stimulation is transduced to the Rho signaling pathways and how it impacts on fibronectin (fbn) fibrillogenesis (FnF). μg (2 days, mission STS-095) led to de-adhesion of fibroblasts and modification of the underlying extracellular matrix. To determine whether GTPases modulated FnF, we generated stable cell lines expressing high level of activated RhoA and Rac1 (QL) as compared to wild type (WI26-WT). After MS application [8% deformation, 1Hz, 15 min., 3 times/day for 1-2 days], we quantified focal adhesion (vinculin, paxillin, FAKY397), f-actin stress fibers (Sf) and FnF with home-developed softwares. We reported that after MS, Sf are more rapidly (30min) formed under the nucleus in Wi26-WT (+100%) and Rac1 (+200%) than in RhoA (+20%). Vinculin & paxillin were only restricted to the cell edge in static conditions and homogeneously distributed after MS in WT and Rac1. The relative area of contacts (vinculin & paxillin) was more dramatically enhanced by MS in Rac1 (+80%) than in WT (+40%) and RhoA (+25%) indicating that new focal contacts are formed under MS and supported the presence of Sf. MS Activation of FAK (FAKY397) was clear in WT and Rac1 and reduced in RhoA. FnF was restricted to cell-cell contacts zone without any change in the relative area of fbn after a 2-days MS. However we found more numerous spots of fbn at the cell center in Rac1 as compared with RhoA & WT suggesting that these fibrillar contacts will grow upon maturation and modulate FnF. The results indicate that MS induces formation of Sf and focal adhesions and enhances FF. RhoA has been shown to induce the formation of Sf and focal adhesions, and Rac1 activation decreases Rho activity in

The Rho GTPase Effector ROCK Regulates Cyclin A, Cyclin D1, and p27Kip1 Levels by Distinct Mechanisms

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Croft, Daniel R.; Olson, Michael F.

2006-01-01

The members of the Rho GTPase family are well known for their regulation of actin cytoskeletal structures. In addition, they influence progression through the cell cycle. The RhoA and RhoC proteins regulate numerous effector proteins, with a central and vital signaling role mediated by the ROCK I and ROCK II serine/threonine kinases. The requirement for ROCK function in the proliferation of numerous cell types has been revealed by studies utilizing ROCK-selective inhibitors such as Y-27632. H...

Yersinia pseudotuberculosis Spatially Controls Activation and Misregulation of Host Cell Rac1.

Directory of Open Access Journals (Sweden)

2005-10-01

Full Text Available Yersinia pseudotuberculosis binds host cells and modulates the mammalian Rac1 guanosine triphosphatase (GTPase at two levels. Activation of Rac1 results from integrin receptor engagement, while misregulation is promoted by translocation of YopE and YopT proteins into target cells. Little is known regarding how these various factors interplay to control Rac1 dynamics. To investigate these competing processes, the localization of Rac1 activation was imaged microscopically using fluorescence resonance energy transfer. In the absence of translocated effectors, bacteria induced activation of the GTPase at the site of bacterial binding. In contrast, the entire cellular pool of Rac1 was inactivated shortly after translocation of YopE RhoGAP. Inactivation required membrane localization of Rac1. The translocated protease YopT had very different effects on Rac1. This protein, which removes the membrane localization site of Rac1, did not inactivate Rac1, but promoted entry of cleaved activated Rac1 molecules into the host cell nucleus, allowing Rac1 to localize with nuclear guanosine nucleotide exchange factors. As was true for YopE, membrane-associated Rac1 was the target for YopT, indicating that the two translocated effectors may compete for the same pool of target protein. Consistent with the observation that YopE inactivation requires membrane localization of Rac1, the presence of YopT in the cell interfered with the action of the YopE RhoGAP. As a result, interaction of target cells with a strain that produces both YopT and YopE resulted in two spatially distinct pools of Rac1: an inactive cytoplasmic pool and an activated nuclear pool. These studies demonstrate that competition between bacterial virulence factors for access to host substrates is controlled by the spatial arrangement of a target protein. In turn, the combined effects of translocated bacterial proteins are to generate pools of a single signaling molecule with distinct localization and

Measurement of Exclusive $\\rho^0 \\rho^0$ Production in Two-Photon Collisions at High $Q^2$ at LEP

CERN Document Server

Achard, P.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M.G.; Anderhub, H.; Andreev, Valery P.; Anselmo, F.; Arefev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay, L.; Baldew, S.V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillere, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B.L.; Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J.J.; Blyth, S.C.; Bobbink, G.J.; Bohm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J.G.; Brochu, F.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Chamizo, M.; Chang, Y.H.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G.M.; Chen, H.F.; Chen, H.S.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; de la Cruz, B.; Cucciarelli, S.; van Dalen, J.A.; de Asmundis, R.; Deglon, P.; Debreczeni, J.; Degre, A.; Dehmelt, K.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M.T.; Duchesneau, D.; Duda, M.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.; Engler, A.; Eppling, F.J.; Extermann, P.; Falagan, M.A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fesefeldt, H.; Fiandrini, E.; Field, J.H.; Filthaut, F.; Fisher, P.H.; Fisher, W.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Iouri; Ganguli, S.N.; Garcia-Abia, Pablo; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z.F.; Grenier, Gerald Jean; Grimm, O.; Gruenewald, M.W.; Guida, M.; van Gulik, R.; Gupta, V.K.; Gurtu, A.; Gutay, L.J.; Haas, D.; Hatzifotiadou, D.; Hebbeker, T.; Herve, Alain; Hirschfelder, J.; Hofer, H.; Hohlmann, M.; Holzner, G.; Hou, S.R.; Hu, Y.; Jin, B.N.; Jones, Lawrence W.; de Jong, P.; Josa-Mutuberria, I.; Kafer, D.; Kaur, M.; Kienzle-Focacci, M.N.; Kim, J.K.; Kirkby, Jasper; Kittel, W.; Klimentov, A.; Konig, A.C.; Kopal, M.; Koutsenko, V.; Kraber, M.; Kraemer, R.W.; Kruger, A.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Le Goff, J.M.; Leiste, R.; Levtchenko, M.; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C.H.; Lin, W.T.; Linde, F.L.; Lista, L.; Liu, Z.A.; Lohmann, W.; Longo, E.; Lu, Y.S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W.G.; Malgeri, L.; Malinin, A.; Mana, C.; Mans, J.; Martin, J.P.; Marzano, F.; Mazumdar, K.; McNeil, R.R.; Mele, S.; Merola, L.; Meschini, M.; Metzger, W.J.; Mihul, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G.B.; Muanza, G.S.; Muijs, A.J.M.; Musicar, B.; Musy, M.; Nagy, S.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Kluge, Hannelies; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.; Passaleva, G.; Patricelli, S.; Paul, Thomas Cantzon; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.; Pioppi, M.; Piroue, P.A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofev, D.; Quartieri, J.; Rahal-Callot, G.; Rahaman, Mohammad Azizur; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P.G.; Ranieri, R.; Raspereza, A.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Riemann, S.; Riles, Keith; Roe, B.P.; Romero, L.; Rosca, A.; Rosier-Lees, S.; Roth, Stefan; Rosenbleck, C.; Rubio, J.A.; Ruggiero, G.; Rykaczewski, H.; Sakharov, A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schafer, C.; Schegelsky, V.; Schopper, H.; Schotanus, D.J.; Sciacca, C.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.; Steuer, M.; Stickland, D.P.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L.Z.; Sushkov, S.; Suter, H.; Swain, J.D.; Szillasi, Z.; Tang, X.W.; Tarjan, P.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, Charles; Ting, Samuel C.C.; Ting, S.M.; Tonwar, S.C.; Toth, J.; Tully, C.; Tung, K.L.; Ulbricht, J.; Valente, E.; Van de Walle, R.T.; Vasquez, R.; Veszpremi, V.; Vesztergombi, G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobev, I.; Vorobyov, A.A.; Wadhwa, M.; Wang, Q.; Wang, X.L.; Wang, Z.M.; Weber, M.; Wienemann, P.; Wilkens, H.; Wynhoff, S.; Xia, L.; Xu, Z.Z.; Yamamoto, J.; Yang, B.Z.; Yang, C.G.; Yang, H.J.; Yang, M.; Yeh, S.C.; Zalite, An.; Zalite, Yu.; Zhang, Z.P.; Zhao, J.; Zhu, G.Y.; Zhu, R.Y.; Zhuang, H.L.; Zichichi, A.; Zimmermann, B.; Zoller, M.

2003-01-01

Exclusive rho rho production in two-photon collisions involving a single highly virtual photon is studied with data collected at LEP at centre-of-mass energies 89GeV rho rho is determined as a function of the photon virtuality, Q^2 and the two-photon centre-of-mass energy, Wgg, in the kinematic region: 1.2GeV^2 < Q^2 < 30GeV^2 and 1.1GeV < Wgg < 3GeV.

A measurement of the branching ratio Σ+→rhoγ/Σ+→rhoπ0

International Nuclear Information System (INIS)

1985-06-01

In an experiment performed in the CERN SPS hyperon beam a value for the branching ratio, Σ + →rhoγ/Σ + →rhoπ 0 of (2.46 sub(-0.35)sup(+0.30))x10 -3 , has been obtained corresponding to a branching ratio Σ + →rhoγ/Σ + → all of (1.27 sub(-0.18)sup(+0.16))x10 -3 . This result is discussed in the context of present understanding of hyperon radiative decays. (author)

BFKL resummation effects in gamma* gamma* to rho rho

Energy Technology Data Exchange (ETDEWEB)

Enberg, R.; Pire, B.; Szymanowski, L.; Wallon, S.

2005-08-11

We calculate the leading order BFKL amplitude for the exclusive diffractive process {gamma}*{sub L}(Q{sub 1}{sup 2}) {gamma}*{sub L}(Q{sub 2}{sup 2}) {yields} {rho}{sub L}{sup 0}{rho}{sub L}{sup 0} in the forward direction, which can be studied in future high energy e{sup +}e{sup -} linear colliders. The resummation effects are very large compared to the fixed-order calculation. We also estimate the next-to-leading logarithmic corrections to the amplitude by using a specific resummation of higher order effects and find a substantial growth with energy, but smaller than in the leading logarithmic approximation.

Wash functions downstream of Rho1 GTPase in a subset of Drosophila immune cell developmental migrations

Science.gov (United States)

Verboon, Jeffrey M.; Rahe, Travis K.; Rodriguez-Mesa, Evelyn; Parkhurst, Susan M.

2015-01-01

Drosophila immune cells, the hemocytes, undergo four stereotypical developmental migrations to populate the embryo, where they provide immune reconnoitering, as well as a number of non–immune-related functions necessary for proper embryogenesis. Here, we describe a role for Rho1 in one of these developmental migrations in which posteriorly located hemocytes migrate toward the head. This migration requires the interaction of Rho1 with its downstream effector Wash, a Wiskott–Aldrich syndrome family protein. Both Wash knockdown and a Rho1 transgene harboring a mutation that prevents Wash binding exhibit the same developmental migratory defect as Rho1 knockdown. Wash activates the Arp2/3 complex, whose activity is needed for this migration, whereas members of the WASH regulatory complex (SWIP, Strumpellin, and CCDC53) are not. Our results suggest a WASH complex–independent signaling pathway to regulate the cytoskeleton during a subset of hemocyte developmental migrations. PMID:25739458

RhoA–Rho kinase and Platelet Activating Factor Stimulation of Ovine Fetal Pulmonary Vascular Smooth Muscle Cell Proliferation

Science.gov (United States)

Renteria, Lissette S.; Austin, Monique; Lazaro, Mariecon; Andrews, Mari Ashley; Lustina, Jennessee; Raj, J. Usha; Ibe, Basil O.

2013-01-01

Objectives Platelet Activating Factor (PAF) is produced by pulmonary vascular smooth muscle Cells (PVSMC). We studied effect of Rho kinase on PAF stimulation of PVSMC proliferation in an attempt to understand a role for RhoA/Rho kinase on PAF-induced ovine fetal pulmonary vascular remodeling. Our hypothesis is that PAF acts through Rho kinase, as one of its downstream signaling, to induce arterial (SMC-PA) and venous (SMC-PV) growth in the hypoxic lung environment of the fetus in utero. Materials and methods Rho kinase and MAPK effects on PAF receptor (PAFR)-mediated cell growth and PAFR expression were studied by DNA synthesis, Western and immunocytochemistry. Effects of constructs T19N and G14V on PAF-induced cell proliferation was also studied. Results Hypoxia increased PVSMC proliferation and the Rho kinase inhibitors, Y-27632 and Fasudil (HA-1077) as well as MAPK inhibitors PD 98059 and SB 203580 attenuated PAF stimulation of cell proliferation. RhoA T19N and G14V stimulated cell proliferation, but co-incubation with PAF did not affect proliferative effects of the constructs. PAFR protein expression was significantly down-regulated in both cell types by both Y-27632 and HA-1077 with comparable profiles. Also cells treated with Y-27632 showed less PAF receptor fluorescence with significant disruption of the cell morphology. Conclusions Our results show that Rho kinase nonspecifically modulates PAFR-mediated responses via a translational modification of PAFR protein and suggest that, in vivo, activation of Rho kinase by PAF may be one other pathway to sustain PAFR-mediated PVSMC growth. PMID:24033386

RhoA-Rho kinase and platelet-activating factor stimulation of ovine foetal pulmonary vascular smooth muscle cell proliferation.

Science.gov (United States)

Renteria, L S; Austin, M; Lazaro, M; Andrews, M A; Lustina, J; Raj, J U; Ibe, B O

2013-10-01

Platelet-activating factor (PAF) is produced by pulmonary vascular smooth muscle cells (PVSMC). We studied effects of Rho kinase on PAF stimulation of PVSMC proliferation in an attempt to understand the role of RhoA/Rho kinase on PAF-induced ovine foetal pulmonary vascular remodelling. Our hypothesis is that PAF acts through Rho kinase, as one of its downstream signals, to induce arterial (SMC-PA) and venous (SMC-PV) cell proliferation in the hypoxic lung environment of the foetus, in utero. Rho kinase and MAPK effects on PAF receptor (PAFR)-mediated cell population expansion, and PAFR expression, were studied by DNA synthesis, western blot analysis and immunocytochemistry. Effects of constructs T19N and G14V on PAF-induced cell proliferation were also investigated. Hypoxia increased PVSMC proliferation and Rho kinase inhibitors, Y-27632 and Fasudil (HA-1077) as well as MAPK inhibitors PD 98059 and SB 203580 attenuated PAF stimulation of cell proliferation. RhoA T19N and G14V stimulated cell proliferation, but co-incubation with PAF did not affect proliferative effects of the constructs. PAFR protein expression was significantly downregulated in both cell types by both Y-27632 and HA-1077, with comparable profiles. Also, cells treated with Y-27632 had less PAF receptor fluorescence with significant disruption of cell morphology. Our results show that Rho kinase non-specifically modulated PAFR-mediated responses by a translational modification of PAFR protein, and suggest that, in vivo, activation of Rho kinase by PAF may be a further pathway to sustain PAFR-mediated PVSMC proliferation. © 2013 John Wiley & Sons Ltd.

The activation of RhoC in vascular endothelial cells is required for the S1P receptor type 2-induced inhibition of angiogenesis.

Science.gov (United States)

Del Galdo, Sabrina; Vettel, Christiane; Heringdorf, Dagmar Meyer Zu; Wieland, Thomas

2013-12-01

Sphingosine-1-phosphate (S1P) is a multifunctional phospholipid inducing a variety of cellular responses in endothelial cells (EC). S1P responses are mediated by five G protein coupled receptors of which three types (S1P1R-S1P3R) have been described to be of importance in vascular endothelial cells (EC). Whereas the S1P1R regulates endothelial barrier function by coupling to Gαi and the monomeric GTPase Rac1, the signaling pathways involved in the S1P-induced regulation of angiogenesis are ill defined. We therefore studied the sprouting of human umbilical vein EC (HUVEC) in vitro and analyzed the activation of the RhoGTPases RhoA and RhoC. Physiological relevant concentrations of S1P (100-300nM) induce a moderate activation of RhoA and RhoC. Inhibition or siRNA-mediated depletion of the S1P2R preferentially decreased the activation of RhoC. Both manipulations caused an increase of sprouting in a spheroid based in vitro sprouting assay. Interestingly, a similar increase in sprouting was detected after effective siRNA-mediated knockdown of RhoC. In contrast, the depletion of RhoA had no influence on sprouting. Furthermore, suppression of the activity of G proteins of the Gα12/13 subfamily by adenoviral overexpression of the regulator of G protein signaling domain of LSC as well as siRNA-mediated knockdown of the Rho specific guanine nucleotide exchange factor leukemia associated RhoGEF (LARG) inhibited the S1P-induced activation of RhoC and concomitantly increased sprouting of HUVEC with similar efficacy. We conclude that the angiogenic sprouting of EC is suppressed via the S1P2R subtype. Thus, the increase in basal sprouting can be attributed to blocking of the inhibitory action of autocrine S1P stimulating the S1P2R. This inhibitory pathway involves the activation of RhoC via Gα12/13 and LARG, while the simultaneously occurring activation of RhoA is apparently dispensable here. © 2013.

A Conserved RhoGAP Limits M-phase Contractility and Coordinates with Microtubule Asters to Restrict Active RhoA to the Cell Equator During Cytokinesis

Science.gov (United States)

Zanin, Esther; Desai, Arshad; Poser, Ina; Toyoda, Yusuke; Andree, Cordula; Moebius, Claudia; Bickle, Marc; Conradt, Barbara; Piekny, Alisa; Oegema, Karen

2014-01-01

SUMMARY During animal cell cytokinesis, the spindle directs contractile ring assembly by activating RhoA in a narrow equatorial zone. Rapid GTPase activating protein (GAP)-mediated inactivation (RhoA flux) is proposed to limit RhoA zone dimensions. Testing the significance of RhoA flux has been hampered by the fact that the GAP targeting RhoA is not known. Here, we identify M-phase GAP (MP-GAP) as the primary GAP targeting RhoA during mitosis/cytokinesis. MP-GAP inhibition caused excessive RhoA activation in M-phase leading to the uncontrolled formation of large cortical protrusions and late cytokinesis failure. RhoA zone width was broadened by attenuation of the centrosomal asters but was not affected by MP-GAP inhibition alone. Simultaneous aster attenuation and MP-GAP inhibition led to RhoA accumulation around the entire cell periphery. These results identify the major GAP restraining RhoA during cell division and delineate the relative contributions of RhoA flux and centrosomal asters in controlling RhoA zone dimensions. PMID:24012485

Complete nucleotide sequence and analysis of two conjugative broad host range plasmids from a marine microbial biofilm.

Directory of Open Access Journals (Sweden)

Peter Norberg

Full Text Available The complete nucleotide sequence of plasmids pMCBF1 and pMCBF6 was determined and analyzed. pMCBF1 and pMCBF6 form a novel clade within the IncP-1 plasmid family designated IncP-1 ς. The plasmids were exogenously isolated earlier from a marine biofilm. pMCBF1 (62 689 base pairs; bp and pMCBF6 (66 729 bp have identical backbones, but differ in their mercury resistance transposons. pMCBF1 carries Tn5053 and pMCBF6 carries Tn5058. Both are flanked by 5 bp direct repeats, typical of replicative transposition. Both insertions are in the vicinity of a resolvase gene in the backbone, supporting the idea that both transposons are "res-site hunters" that preferably insert close to and use external resolvase functions. The similarity of the backbones indicates recent insertion of the two transposons and the ongoing dynamics of plasmid evolution in marine biofilms. Both plasmids also carry the insertion sequence ISPst1, albeit without flanking repeats. ISPs1is located in an unusual site within the control region of the plasmid. In contrast to most known IncP-1 plasmids the pMCBF1/pMCBF6 backbone has no insert between the replication initiation gene (trfA and the vegetative replication origin (oriV. One pMCBF1/pMCBF6 block of about 2.5 kilo bases (kb has no similarity with known sequences in the databases. Furthermore, insertion of three genes with similarity to the multidrug efflux pump operon mexEF and a gene from the NodT family of the tripartite multi-drug resistance-nodulation-division (RND system in Pseudomonas aeruginosa was found. They do not seem to confer antibiotic resistance to the hosts of pMCBF1/pMCBF6, but the presence of RND on promiscuous plasmids may have serious implications for the spread of antibiotic multi-resistance.

The conserved clag multigene family of malaria parasites: essential roles in host-pathogen interaction.

Science.gov (United States)

Gupta, Ankit; Thiruvengadam, Girija; Desai, Sanjay A

2015-01-01

The clag multigene family is strictly conserved in malaria parasites, but absent from neighboring genera of protozoan parasites. Early research pointed to roles in merozoite invasion and infected cell cytoadherence, but more recent studies have implicated channel-mediated uptake of ions and nutrients from host plasma. Here, we review the current understanding of this gene family, which appears to be central to host-parasite interactions and an important therapeutic target. Published by Elsevier Ltd.

Different roles of the small GTPases Rac1, Cdc42, and RhoG in CALEB/NGC-induced dendritic tree complexity.

Science.gov (United States)

Schulz, Jana; Franke, Kristin; Frick, Manfred; Schumacher, Stefan

2016-10-01

Rho GTPases play prominent roles in the regulation of cytoskeletal reorganization. Many aspects have been elaborated concerning the individual functions of Rho GTPases in distinct signaling pathways leading to cytoskeletal rearrangements. However, major questions have yet to be answered regarding the integration and the signaling hierarchy of different Rho GTPases in regulating the cytoskeleton in fundamental physiological events like neuronal process differentiation. Here, we investigate the roles of the small GTPases Rac1, Cdc42, and RhoG in defining dendritic tree complexity stimulated by the transmembrane epidermal growth factor family member CALEB/NGC. Combining gain-of-function and loss-of-function analysis in primary hippocampal neurons, we find that Rac1 is essential for CALEB/NGC-mediated dendritic branching. Cdc42 reduces the complexity of dendritic trees. Interestingly, we identify the palmitoylated isoform of Cdc42 to adversely affect dendritic outgrowth and dendritic branching, whereas the prenylated Cdc42 isoform does not. In contrast to Rac1, CALEB/NGC and Cdc42 are not directly interconnected in regulating dendritic tree complexity. Unlike Rac1, the Rac1-related GTPase RhoG reduces the complexity of dendritic trees by acting upstream of CALEB/NGC. Mechanistically, CALEB/NGC activates Rac1, and RhoG reduces the amount of CALEB/NGC that is located at the right site for Rac1 activation at the cell membrane. Thus, Rac1, Cdc42, and RhoG perform very specific and non-redundant functions at different levels of hierarchy in regulating dendritic tree complexity induced by CALEB/NGC. Rho GTPases play a prominent role in dendritic branching. CALEB/NGC is a transmembrane member of the epidermal growth factor (EGF) family that mediates dendritic branching, dependent on Rac1. CALEB/NGC stimulates Rac1 activity. RhoG inhibits CALEB/NGC-mediated dendritic branching by decreasing the amount of CALEB/NGC at the plasma membrane. Palmitoylated, but not prenylated form

RhoA and RhoC are involved in stromal cell-derived factor-1-induced cell migration by regulating F-actin redistribution and assembly.

Science.gov (United States)

Luo, Jixian; Li, Dingyun; Wei, Dan; Wang, Xiaoguang; Wang, Lan; Zeng, Xianlu

2017-12-01

Stromal cell-derived factor-1 (SDF-1) signaling is important to the maintenance and progression of T-cell acute lymphoblastic leukemia by inducing chemotaxis migration. To identify the mechanism of SDF-1 signaling in the migration of T-ALL, Jurkat acute lymphoblastic leukemia cells were used. Results showed that SDF-1 induces Jurkat cell migration by F-actin redistribution and assembly, which is dependent on Rho activity. SDF-1 induced RhoA and RhoC activation, as well as reactive oxygen species (ROS) production, which was inhibited by Rho inhibitor. The Rho-dependent ROS production led to subsequent cytoskeleton redistribution and assembly in the process of migration. Additionally, RhoA and RhoC were involved in SDF-1-induced Jurkat cell migration. Taken together, we found a SDF-1/CXCR4-RhoA and RhoC-ROS-cytoskeleton pathway that regulates Jurkat cell migration in response to SDF-1. This work will contribute to a clearer insight into the migration mechanism of acute lymphoblastic leukemia.

Knockout of the PKN Family of Rho Effector Kinases Reveals a Non-redundant Role for PKN2 in Developmental Mesoderm Expansion

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Ivan Quétier

2016-01-01

Full Text Available In animals, the protein kinase C (PKC family has expanded into diversely regulated subgroups, including the Rho family-responsive PKN kinases. Here, we describe knockouts of all three mouse PKN isoforms and reveal that PKN2 loss results in lethality at embryonic day 10 (E10, with associated cardiovascular and morphogenetic defects. The cardiovascular phenotype was not recapitulated by conditional deletion of PKN2 in endothelial cells or the developing heart. In contrast, inducible systemic deletion of PKN2 after E7 provoked collapse of the embryonic mesoderm. Furthermore, mouse embryonic fibroblasts, which arise from the embryonic mesoderm, depend on PKN2 for proliferation and motility. These cellular defects are reflected in vivo as dependence on PKN2 for mesoderm proliferation and neural crest migration. We conclude that failure of the mesoderm to expand in the absence of PKN2 compromises cardiovascular integrity and development, resulting in lethality.

T1R3 homomeric sweet taste receptor regulates adipogenesis through Gαs-mediated microtubules disassembly and Rho activation in 3T3-L1 cells.

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Yosuke Masubuchi

Full Text Available We previously reported that 3T3-L1 cells express a functional sweet taste receptor possibly as a T1R3 homomer that is coupled to Gs and negatively regulates adipogenesis by a Gαs-mediated but cAMP-independent mechanism. Here, we show that stimulation of this receptor with sucralose or saccharin induced disassembly of the microtubules in 3T3-L1 preadipocytes, which was attenuated by overexpression of the dominant-negative mutant of Gαs (Gαs-G226A. In contrast, overexpression of the constitutively active mutant of Gαs (Gαs-Q227L as well as treatment with cholera toxin or isoproterenol but not with forskolin caused disassembly of the microtubules. Sweetener-induced microtubule disassembly was accompanied by activation of RhoA and Rho-associated kinase (ROCK. This was attenuated with by knockdown of GEF-H1, a microtubule-localized guanine nucleotide exchange factor for Rho GTPase. Furthermore, overexpression of the dominant-negative mutant of RhoA (RhoA-T19N blocked sweetener-induced dephosphorylation of Akt and repression of PPARγ and C/EBPα in the early phase of adipogenic differentiation. These results suggest that the T1R3 homomeric sweet taste receptor negatively regulates adipogenesis through Gαs-mediated microtubule disassembly and consequent activation of the Rho/ROCK pathway.

Interferon induced IFIT family genes in host antiviral defense.

Science.gov (United States)

Zhou, Xiang; Michal, Jennifer J; Zhang, Lifan; Ding, Bo; Lunney, Joan K; Liu, Bang; Jiang, Zhihua

2013-01-01

Secretion of interferons (IFNs) from virus-infected cells is a hallmark of host antiviral immunity and in fact, IFNs exert their antiviral activities through the induction of antiviral proteins. The IFN-induced protein with tetratricopeptide repeats (IFITs) family is among hundreds of IFN-stimulated genes. This family contains a cluster of duplicated loci. Most mammals have IFIT1, IFIT2, IFIT3 and IFIT5; however, bird, marsupial, frog and fish have only IFIT5. Regardless of species, IFIT5 is always adjacent to SLC16A12. IFIT family genes are predominantly induced by type I and type III interferons and are regulated by the pattern recognition and the JAK-STAT signaling pathway. IFIT family proteins are involved in many processes in response to viral infection. However, some viruses can escape the antiviral functions of the IFIT family by suppressing IFIT family genes expression or methylation of 5' cap of viral molecules. In addition, the variants of IFIT family genes could significantly influence the outcome of hepatitis C virus (HCV) therapy. We believe that our current review provides a comprehensive picture for the community to understand the structure and function of IFIT family genes in response to pathogens in human, as well as in animals.

Observation of the ${B^0 \\to \\rho^0 \\rho^0}$ decay from an amplitude analysis of ${B^0 \\to (\\pi^+\\pi^-)(\\pi^+\\pi^-)}$ decays

CERN Document Server

Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casanova Mohr, Raimon; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cavallero, Giovanni; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Di Ruscio, Francesco; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gastaldi, Ugo; Gauld, Rhorry; Gavardi, Laura; Gazzoni, Giulio; Geraci, Angelo; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Gianì, Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Humair, Thibaud; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Kenzie, Matthew; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lowdon, Peter; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Mitzel, Dominik Stefan; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Katharina; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Osorio Rodrigues, Bruno; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Aranzazu; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantin; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Poikela, Tuomas; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skillicorn, Ian; Skwarnicki, Tomasz; Smith, Anthony; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Sterpka, Christopher Francis; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szumlak, Tomasz; T'Jampens, Stephane; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Todd, Jacob; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viana Barbosa, Joao Vitor; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wiedner, Dirk; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang

2015-01-01

Proton-proton collision data recorded in 2011 and 2012 by the LHCb experiment, corresponding to an integrated luminosity of 3.0 fb$^{-1}$i, are analysed to search for the charmless ${B^0 \\to \\rho^0 \\rho^0}$ decay. More than 600 ${B^0 \\to (\\pi^+\\pi^-)(\\pi^+\\pi^-)}$ signal decays are selected and used to perform an amplitude analysis from which the ${B^0 \\to \\rho^0 \\rho^0}$ decay is observed for the first time with 7.1 standard deviations significance. The fraction of ${B^0 \\to \\rho^0 \\rho^0}$ decays yielding a longitudinally polarised final state is measured to be $fL = 0.745^{+0.048}_{-0.058} ({\\rm stat}) \\pm 0.034 ({\\rm syst})$. The ${B^0 \\to \\rho^0 \\rho^0}$ branching fraction, using the ${B^0 \\to \\phi K^*(892)^{0}}$ decay as reference, is also reported as $\\mathcal B (B^0 \\to \\rho^0 \\rho^0) = (0.94 \\pm 0.17 ({\\rm stat}) \\pm 0.09 ({\\rm syst}) \\pm 0.06 ({\\rm BF})) \\times 10^{-6}$.

Plant Rho-type (Rop) GTPase-dependent activation of receptor-like cytoplasmic kinases in vitro.

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Dorjgotov, Dulguun; Jurca, Manuela E; Fodor-Dunai, Csilla; Szucs, Attila; Otvös, Krisztina; Klement, Eva; Bíró, Judit; Fehér, Attila

2009-04-02

Plants have evolved distinct mechanisms to link Rho-type (Rop) GTPases to downstream signaling pathways as compared to other eukaryotes. Here, experimental data are provided that members of the Medicago, as well as Arabidopsis, receptor-like cytoplasmic kinase family (RLCK Class VI) were strongly and specifically activated by GTP-bound Rop GTPases in vitro. Deletion analysis indicated that the residues implicated in the interaction might be distributed on various parts of the kinases. Using a chimaeric Rop GTPase protein, the importance of the Rho-insert region in kinase activation could also be verified. These data strengthen the possibility that RLCKs may serve as Rop GTPase effectors in planta.

Cyclic nucleotide specific phosphodiesterases of Leishmania major

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Linder Markus

2006-03-01

Full Text Available Abstract Background Leishmania represent a complex of important human pathogens that belong to the systematic order of the kinetoplastida. They are transmitted between their human and mammalian hosts by different bloodsucking sandfly vectors. In their hosts, the Leishmania undergo several differentiation steps, and their coordination and optimization crucially depend on numerous interactions between the parasites and the physiological environment presented by the fly and human hosts. Little is still known about the signalling networks involved in these functions. In an attempt to better understand the role of cyclic nucleotide signalling in Leishmania differentiation and host-parasite interaction, we here present an initial study on the cyclic nucleotide-specific phosphodiesterases of Leishmania major. Results This paper presents the identification of three class I cyclic-nucleotide-specific phosphodiesterases (PDEs from L. major, PDEs whose catalytic domains exhibit considerable sequence conservation with, among other, all eleven human PDE families. In contrast to other protozoa such as Dictyostelium, or fungi such as Saccharomyces cerevisiae, Candida ssp or Neurospora, no genes for class II PDEs were found in the Leishmania genomes. LmjPDEA contains a class I catalytic domain at the C-terminus of the polypeptide, with no other discernible functional domains elsewhere. LmjPDEB1 and LmjPDEB2 are coded for by closely related, tandemly linked genes on chromosome 15. Both PDEs contain two GAF domains in their N-terminal region, and their almost identical catalytic domains are located at the C-terminus of the polypeptide. LmjPDEA, LmjPDEB1 and LmjPDEB2 were further characterized by functional complementation in a PDE-deficient S. cerevisiae strain. All three enzymes conferred complementation, demonstrating that all three can hydrolyze cAMP. Recombinant LmjPDEB1 and LmjPDEB2 were shown to be cAMP-specific, with Km values in the low micromolar range

Tetramethylpyrazine Protects Against Oxygen-Glucose Deprivation-Induced Brain Microvascular Endothelial Cells Injury via Rho/Rho-kinase Signaling Pathway.

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Yang, Guang; Qian, Chen; Wang, Ning; Lin, Chenyu; Wang, Yan; Wang, Guangyun; Piao, Xinxin

2017-05-01

Tetramethylpyrazine (TMP, also known as Ligustrazine), which is isolated from Chinese Herb Medicine Ligustium wollichii Franchat (Chuan Xiong), has been widely used in China for the treatment of ischemic stroke by Chinese herbalists. Brain microvascular endothelial cells (BMECs) are the integral parts of the blood-brain barrier (BBB), protecting BMECs against oxygen-glucose deprivation (OGD) which is important for the treatment of ischemic stroke. Here, we investigated the protective mechanisms of TMP, focusing on OGD-injured BMECs and the Rho/Rho-kinase (Rho-associated kinases, ROCK) signaling pathway. The model of OGD-injured BMECs was established in this study. BMECs were identified by von Willebrand factor III staining and exposed to fasudil, or TMP at different concentrations (14.3, 28.6, 57.3 µM) for 2 h before 24 h of OGD injury. The effect of each treatment was examined by cell viability assays, measurement of intracellular reactive oxygen species (ROS), and transendothelial electric resistance and western blot analysis (caspase-3, endothelial nitric oxide synthase (eNOS), RhoA, Rac1). Our results show that TMP significantly attenuated apoptosis and the permeability of BMECs induced by OGD. In addition, TMP could notably down-regulate the characteristic proteins in Rho/ROCK signaling pathway such as RhoA and Rac1, which triggered abnormal changes of eNOS and ROS, respectively. Altogether, our results show that TMP has a strong protective effect against OGD-induced BMECs injury and suggest that the mechanism might be related to the inhibition of the Rho/ROCK signaling pathway.

BFKL resummation effects in {gamma}{sup *}{gamma}{sup *}{yields}{rho}{rho}

Energy Technology Data Exchange (ETDEWEB)

Enberg, R. [Ecole Polytechnique, CPHT, Palaiseau (France); Lawrence Berkeley National Laboratory, Berkeley (United States); Pire, B. [Ecole Polytechnique, CPHT, Palaiseau (France); Szymanowski, L. [Soltan Institute for Nuclear Studies, Warsaw (Poland); Universite de Liege, Liege (Belgium); Wallon, S. [LPT, Universite Paris-Sud, Orsay (France)

2006-03-15

We calculate the leading order BFKL amplitude for the exclusive diffractive process {gamma}{sup *}{sub L}(Q{sub 1}{sup 2}){gamma}{sup *}{sub L}(Q{sub 2}{sup 2}){yields}{rho}{sub L}{sup 0}{rho}{sub L}{sup 0} in the forward direction, which can be studied in future high energy e{sup +}e{sup -} linear colliders. The resummation effects are very large compared to the fixed-order calculation. We also estimate the next-to-leading logarithmic corrections to the amplitude by using a specific resummation of higher order effects and find a substantial growth with energy, but smaller than in the leading logarithmic approximation. (orig.)

Protein kinase C-α signals P115RhoGEF phosphorylation and RhoA activation in TNF-α-induced mouse brain microvascular endothelial cell barrier dysfunction

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Deng Xiaolu

2011-04-01

Full Text Available Abstract Background Tumor necrosis factor-α (TNF-α, a proinflammatory cytokine, is capable of activating the small GTPase RhoA, which in turn contributes to endothelial barrier dysfunction. However, the underlying signaling mechanisms remained undefined. Therefore, we aimed to determine the role of protein kinase C (PKC isozymes in the mechanism of RhoA activation and in signaling TNF-α-induced mouse brain microvascular endothelial cell (BMEC barrier dysfunction. Methods Bend.3 cells, an immortalized mouse brain endothelial cell line, were exposed to TNF-α (10 ng/mL. RhoA activity was assessed by pull down assay. PKC-α activity was measured using enzyme assasy. BMEC barrier function was measured by transendothelial electrical resistance (TER. p115RhoGEF phosphorylation was detected by autoradiography followed by western blotting. F-actin organization was observed by rhodamine-phalloidin staining. Both pharmacological inhibitors and knockdown approaches were employed to investigate the role of PKC and p115RhoGEF in TNF-α-induced RhoA activation and BMEC permeability. Results We observed that TNF-α induces a rapid phosphorylation of p115RhoGEF, activation of PKC and RhoA in BMECs. Inhibition of conventional PKC by Gö6976 mitigated the TNF-α-induced p115RhoGEF phosphorylation and RhoA activation. Subsequently, we found that these events are regulated by PKC-α rather than PKC-β by using shRNA. In addition, P115-shRNA and n19RhoA (dominant negative mutant of RhoA transfections had no effect on mediating TNF-α-induced PKC-α activation. These data suggest that PKC-α but not PKC-β acts as an upstream regulator of p115RhoGEF phosphorylation and RhoA activation in response to TNF-α. Moreover, depletion of PKC-α, of p115RhoGEF, and inhibition of RhoA activation also prevented TNF-α-induced stress fiber formation and a decrease in TER. Conclusions Taken together, our results show that PKC-α phosphorylation of p115RhoGEF mediates TNF

The role of interleukin-1 family members in the host defence against Aspergillus fumigatus.

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Gresnigt, Mark S; van de Veerdonk, Frank L

2014-12-01

The interleukin (IL)-1 family consists of 11 members, which all play significant roles in regulating inflammatory responses in the host. IL-1α and IL-1β exert potent pro-inflammatory effects and are key players in the recruitment of neutrophils to the site of inflammation. Protective anti-Aspergillus host responses during the early stages of invasive aspergillosis are critically dependent on neutrophil recruitment, and several lines of evidence support that there is an important role for IL-1 in this process. However, IL-1-mediated inflammation needs to be tightly regulated, since uncontrolled inflammation can result in inflammatory pathology and thereby be detrimental for the host. Aspergillus-induced IL-1-mediated inflammation could therefore be amendable for IL-1 blockade under specific circumstances. This review describes the current understanding of the role of IL-1 family members in the host response against Aspergillus fumigatus and highlights the importance of balanced IL-1 responses in aspergillosis.

The Arf GTPase-activating protein family is exploited by Salmonella enterica serovar Typhimurium to invade nonphagocytic host cells.

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Davidson, Anthony C; Humphreys, Daniel; Brooks, Andrew B E; Hume, Peter J; Koronakis, Vassilis

2015-02-10

To establish intracellular infections, Salmonella bacteria trigger host cell membrane ruffling and invasion by subverting cellular Arf guanine nucleotide exchange factors (GEFs) that activate Arf1 and Arf6 GTPases by promoting GTP binding. A family of cellular Arf GTPase-activating proteins (GAPs) can downregulate Arf signaling by stimulating GTP hydrolysis, but whether they do this during infection is unknown. Here, we uncovered a remarkable role for distinct Arf GAP family members in Salmonella invasion. The Arf6 GAPs ACAP1 and ADAP1 and the Arf1 GAP ASAP1 localized at Salmonella-induced ruffles, which was not the case for the plasma membrane-localized Arf6 GAPs ARAP3 and GIT1 or the Golgi-associated Arf1 GAP1. Surprisingly, we found that loss of ACAP1, ADAP1, or ASAP1 impaired Salmonella invasion, revealing that GAPs cannot be considered mere terminators of cytoskeleton remodeling. Salmonella invasion was restored in Arf GAP-depleted cells by expressing fast-cycling Arf derivatives, demonstrating that Arf GTP/GDP cycles facilitate Salmonella invasion. Consistent with this view, both constitutively active and dominant-negative Arf derivatives that cannot undergo GTP/GDP cycles inhibited invasion. Furthermore, we demonstrated that Arf GEFs and GAPs colocalize at invading Salmonella and collaborate to drive Arf1-dependent pathogen invasion. This study revealed that Salmonella bacteria exploit a remarkable interplay between Arf GEFs and GAPs to direct cycles of Arf GTPase activation and inactivation. These cycles drive Salmonella cytoskeleton remodeling and enable intracellular infections. To initiate infections, the Salmonella bacterial pathogen remodels the mammalian actin cytoskeleton and invades host cells by subverting host Arf GEFs that activate Arf1 and Arf6 GTPases. Cellular Arf GAPs deactivate Arf GTPases and negatively regulate cell processes, but whether they target Arfs during infection is unknown. Here, we uncovered an important role for the Arf GAP

The Human SLC25A33 and SLC25A36 Genes of Solute Carrier Family 25 Encode Two Mitochondrial Pyrimidine Nucleotide Transporters*

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Di Noia, Maria Antonietta; Todisco, Simona; Cirigliano, Angela; Rinaldi, Teresa; Agrimi, Gennaro; Iacobazzi, Vito; Palmieri, Ferdinando

2014-01-01

The human genome encodes 53 members of the solute carrier family 25 (SLC25), also called the mitochondrial carrier family, many of which have been shown to transport inorganic anions, amino acids, carboxylates, nucleotides, and coenzymes across the inner mitochondrial membrane, thereby connecting cytosolic and matrix functions. Here two members of this family, SLC25A33 and SLC25A36, have been thoroughly characterized biochemically. These proteins were overexpressed in bacteria and reconstituted in phospholipid vesicles. Their transport properties and kinetic parameters demonstrate that SLC25A33 transports uracil, thymine, and cytosine (deoxy)nucleoside di- and triphosphates by an antiport mechanism and SLC25A36 cytosine and uracil (deoxy)nucleoside mono-, di-, and triphosphates by uniport and antiport. Both carriers also transported guanine but not adenine (deoxy)nucleotides. Transport catalyzed by both carriers was saturable and inhibited by mercurial compounds and other inhibitors of mitochondrial carriers to various degrees. In confirmation of their identity (i) SLC25A33 and SLC25A36 were found to be targeted to mitochondria and (ii) the phenotypes of Saccharomyces cerevisiae cells lacking RIM2, the gene encoding the well characterized yeast mitochondrial pyrimidine nucleotide carrier, were overcome by expressing SLC25A33 or SLC25A36 in these cells. The main physiological role of SLC25A33 and SLC25A36 is to import/export pyrimidine nucleotides into and from mitochondria, i.e. to accomplish transport steps essential for mitochondrial DNA and RNA synthesis and breakdown. PMID:25320081

[The impact of the visit of nursing on the necessities of the host families of ICU].

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Simoni, Rosemary Cristina Marques; Silva, Maria Júlia Paes da

2012-10-01

Study of a quantitative approach that aimed to implement the Visiting Nurse ICU adult and check and meet the main needs for information and verbalized by host families. After approval of the CEP of the HU-USP was asked if the family would like to receive some information on the part of nursing. All family members wanted to receive information from nurses in three visits with each family. The themes of doubt among the most familiar were the patient's clinical state and discharged from the ICU. We found that the average number of questions decreased from the first to third visit. The Visiting Nurse attended the main needs of the host family information and answering your questions about the nursing care provided to patients. It was also observed that the doubts and anxieties of family members decreased during the day, emphasizing the need that contact of Nurses and Families.

Effect of QSKL on MAPK and RhoA Pathways in a Rat Model of Heart Failure

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Kai Xia

2017-01-01

Full Text Available Qishenkeli (QSKL is one of the Chinese medicine formulae for treating heart failure and has been shown to have an antifibrotic effect. However, the mechanism of its therapeutic effects remains unclear. In this study, we aimed to explore whether QSKL could exert an antifibrotic effect by attenuating ras homolog family member A (RhoA and mitogen activated protein kinase (MAPK pathways. Rats were randomly divided into sham group, model group, QSKL group, and positive control group. Heart failure was induced by ligation of the left ventricle anterior descending artery. Cardiac functions were measured by echocardiography and collagen deposition was assessed by Masson staining. Expressions of the key molecules involved in the RhoA and MAPK pathways were also measured. Twenty-one days after surgery, cardiac functions were severely impaired and collagen deposition was remarkable, while QSKL treatment could improve heart functions and alleviate collagen deposition. Further results demonstrated that the effects may be mediated by suppressing expressions of extracellular signal-regulated kinase (ERK and c-Jun N-terminal kinase (JNK. Moreover, expressions of RhoA, Rho-associated protein kinase 1/2 (ROCK1/2, and phosphorylated myosin light chain (p-MLC were also downregulated by QSKL compared with the model group. The cardioprotective mechanism of QSKL on heart failure is probably mediated by regulating both the MAPK and RhoA signaling pathways.

Merkel Cell Polyomavirus Small T Antigen Drives Cell Motility via Rho-GTPase-Induced Filopodium Formation.

Science.gov (United States)

Stakaitytė, Gabrielė; Nwogu, Nnenna; Dobson, Samuel J; Knight, Laura M; Wasson, Christopher W; Salguero, Francisco J; Blackbourn, David J; Blair, G Eric; Mankouri, Jamel; Macdonald, Andrew; Whitehouse, Adrian

2018-01-15

Cell motility and migration is a complex, multistep, and multicomponent process intrinsic to progression and metastasis. Motility is dependent on the activities of integrin receptors and Rho family GTPases, resulting in the remodeling of the actin cytoskeleton and formation of various motile actin-based protrusions. Merkel cell carcinoma (MCC) is an aggressive skin cancer with a high likelihood of recurrence and metastasis. Merkel cell polyomavirus (MCPyV) is associated with the majority of MCC cases, and MCPyV-induced tumorigenesis largely depends on the expression of the small tumor antigen (ST). Since the discovery of MCPyV, a number of mechanisms have been suggested to account for replication and tumorigenesis, but to date, little is known about potential links between MCPyV T antigen expression and the metastatic nature of MCC. Previously, we described the action of MCPyV ST on the microtubule network and how it impacts cell motility and migration. Here, we demonstrate that MCPyV ST affects the actin cytoskeleton to promote the formation of filopodia through a mechanism involving the catalytic subunit of protein phosphatase 4 (PP4C). We also show that MCPyV ST-induced cell motility is dependent upon the activities of the Rho family GTPases Cdc42 and RhoA. In addition, our results indicate that the MCPyV ST-PP4C interaction results in the dephosphorylation of β 1 integrin, likely driving the cell motility pathway. These findings describe a novel mechanism by which a tumor virus induces cell motility, which may ultimately lead to cancer metastasis, and provides opportunities and strategies for targeted interventions for disseminated MCC. IMPORTANCE Merkel cell polyomavirus (MCPyV) is the most recently discovered human tumor virus. It causes the majority of cases of Merkel cell carcinoma (MCC), an aggressive skin cancer. However, the molecular mechanisms implicating MCPyV-encoded proteins in cancer development are yet to be fully elucidated. This study builds

Role of the Small GTPase Rho3 in Golgi/Endosome trafficking through functional interaction with adaptin in Fission Yeast.

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Ayako Kita

Full Text Available BACKGROUND: We had previously identified the mutant allele of apm1(+ that encodes a homolog of the mammalian µ1A subunit of the clathrin-associated adaptor protein-1 (AP-1 complex, and we demonstrated the role of Apm1 in Golgi/endosome trafficking, secretion, and vacuole fusion in fission yeast. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we isolated rho3(+, which encodes a Rho-family small GTPase, an important regulator of exocystosis, as a multicopy-suppressor of the temperature-sensitive growth of the apm1-1 mutant cells. Overexpression of Rho3 suppressed the Cl(- sensitivity and immunosuppressant sensitivity of the apm1-1 mutant cells. Overexpression of Rho3 also suppressed the fragmentation of vacuoles, and the accumulation of v-SNARE Syb1 in Golgi/endosomes and partially suppressed the defective secretion associated with apm1-deletion cells. Notably, electron microscopic observation of the rho3-deletion cells revealed the accumulation of abnormal Golgi-like structures, vacuole fragmentation, and accumulation of secretory vesicles; these phenotypes were very similar to those of the apm1-deletion cells. Furthermore, the rho3-deletion cells and apm1-deletion cells showed very similar phenotypic characteristics, including the sensitivity to the immunosuppressant FK506, the cell wall-damaging agent micafungin, Cl(-, and valproic acid. Green fluorescent protein (GFP-Rho3 was localized at Golgi/endosomes as well as the plasma membrane and division site. Finally, Rho3 was shown to form a complex with Apm1 as well as with other subunits of the clathrin-associated AP-1 complex in a GTP- and effector domain-dependent manner. CONCLUSIONS/SIGNIFICANCE: Taken together, our findings reveal a novel role of Rho3 in the regulation of Golgi/endosome trafficking and suggest that clathrin-associated adaptor protein-1 and Rho3 co-ordinate in intracellular transport in fission yeast. To the best of our knowledge, this study provides the first evidence

The human SLC25A33 and SLC25A36 genes of solute carrier family 25 encode two mitochondrial pyrimidine nucleotide transporters.

Science.gov (United States)

Di Noia, Maria Antonietta; Todisco, Simona; Cirigliano, Angela; Rinaldi, Teresa; Agrimi, Gennaro; Iacobazzi, Vito; Palmieri, Ferdinando

2014-11-28

The human genome encodes 53 members of the solute carrier family 25 (SLC25), also called the mitochondrial carrier family, many of which have been shown to transport inorganic anions, amino acids, carboxylates, nucleotides, and coenzymes across the inner mitochondrial membrane, thereby connecting cytosolic and matrix functions. Here two members of this family, SLC25A33 and SLC25A36, have been thoroughly characterized biochemically. These proteins were overexpressed in bacteria and reconstituted in phospholipid vesicles. Their transport properties and kinetic parameters demonstrate that SLC25A33 transports uracil, thymine, and cytosine (deoxy)nucleoside di- and triphosphates by an antiport mechanism and SLC25A36 cytosine and uracil (deoxy)nucleoside mono-, di-, and triphosphates by uniport and antiport. Both carriers also transported guanine but not adenine (deoxy)nucleotides. Transport catalyzed by both carriers was saturable and inhibited by mercurial compounds and other inhibitors of mitochondrial carriers to various degrees. In confirmation of their identity (i) SLC25A33 and SLC25A36 were found to be targeted to mitochondria and (ii) the phenotypes of Saccharomyces cerevisiae cells lacking RIM2, the gene encoding the well characterized yeast mitochondrial pyrimidine nucleotide carrier, were overcome by expressing SLC25A33 or SLC25A36 in these cells. The main physiological role of SLC25A33 and SLC25A36 is to import/export pyrimidine nucleotides into and from mitochondria, i.e. to accomplish transport steps essential for mitochondrial DNA and RNA synthesis and breakdown. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Role of Nucleotide-Binding Oligomerization Domain-Containing (NOD 2 in Host Defense during Pneumococcal Pneumonia.

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Tijmen J Hommes

Full Text Available Streptococcus (S. pneumoniae is the most common causative pathogen in community-acquired pneumonia. Nucleotide-binding oligomerization domain-containing (NOD 2 is a pattern recognition receptor located in the cytosol of myeloid cells that is able to detect peptidoglycan fragments of S. pneumoniae. We here aimed to investigate the role of NOD2 in the host response during pneumococcal pneumonia. Phagocytosis of S. pneumoniae was studied in NOD2 deficient (Nod2-/- and wild-type (Wt alveolar macrophages and neutrophils in vitro. In subsequent in vivo experiments Nod2-/- and Wt mice were inoculated with serotype 2 S. pneumoniae (D39, an isogenic capsule locus deletion mutant (D39Δcps or serotype 3 S. pneumoniae (6303 via the airways, and bacterial growth and dissemination and the lung inflammatory response were evaluated. Nod2-/- alveolar macrophages and blood neutrophils displayed a reduced capacity to internalize pneumococci in vitro. During pneumonia caused by S. pneumoniae D39 Nod2-/- mice were indistinguishable from Wt mice with regard to bacterial loads in lungs and distant organs, lung pathology and neutrophil recruitment. While Nod2-/- and Wt mice also had similar bacterial loads after infection with the more virulent S. pneumoniae 6303 strain, Nod2-/- mice displayed a reduced bacterial clearance of the normally avirulent unencapsulated D39Δcps strain. These results suggest that NOD2 does not contribute to host defense during pneumococcal pneumonia and that the pneumococcal capsule impairs recognition of S. pneumoniae by NOD2.

Exclusive {rho}{sup 0} production at HERMES

Energy Technology Data Exchange (ETDEWEB)

Rostomyan, Armine Armand

2008-11-15

In this thesis the exclusive electroproduction of {rho}{sup 0} mesons is analyzed using the data accumulated with the HERMES spectrometer in the years 2002-2005 by scattering the lepton beam of the HERA accelerator of the internal target of HERMES filled with transversely polarized hydrogen gas atoms. The {rho}{sup 0} production mechanism and, in a model-dependent way, the structure of the nucleon are studied by measuring the spin-density matrix elements (SDMEs), which parameterize the {rho}{sup 0} production and decay angular distribution. The decomposition of the angular distribution in terms of SDMEs was previously done for both polarized and unpolarized lepton beam and unpolarized target. Recently, the angular distribution was decomposed in terms of SDMEs also for a transversely polarized target. A first measurement of the 30 'transverse' SDMEs is reported in this thesis, yielding information on the degree of s-channel helicity conservation and natural-parity exchange in the case of a transversely polarized target. The measured SDMEs are implemented into the rhoMC Monte Carlo generator, which is currently the only one capable of fully simulating the exclusive {rho}{sup 0} production and decay for both unpolarized and polarized beam and target. The interest in SDMEs for a polarized target arose after it was shown that at leading twist the corresponding SDMEs can be related to the azimuthal transverse target-spin asymmetry in the cross section of exclusive {rho}{sup 0} production which is sensitive to the unknown nucleon helicity-ip GPDs. Since the GPD formalism is only valid for longitudinally polarized vector mesons produced by longitudinal photons, for the first time the transverse target-spin asymmetry of longitudinally polarized {rho}{sup 0} mesons is extracted and compared to the available theoretical predictions, specically considering possible problems with next-to-leading order corrections. (orig.)

Exclusive {rho}{sup 0} production at HERMES

Energy Technology Data Exchange (ETDEWEB)

Rostomyan, Armine Armand

2008-11-15

In this thesis the exclusive electroproduction of {rho}{sup 0} mesons is analyzed using the data accumulated with the HERMES spectrometer in the years 2002-2005 by scattering the lepton beam of the HERA accelerator of the internal target of HERMES filled with transversely polarized hydrogen gas atoms. The {rho}{sup 0} production mechanism and, in a model-dependent way, the structure of the nucleon are studied by measuring the spin-density matrix elements (SDMEs), which parameterize the {rho}{sup 0} production and decay angular distribution. The decomposition of the angular distribution in terms of SDMEs was previously done for both polarized and unpolarized lepton beam and unpolarized target. Recently, the angular distribution was decomposed in terms of SDMEs also for a transversely polarized target. A first measurement of the 30 'transverse' SDMEs is reported in this thesis, yielding information on the degree of s-channel helicity conservation and natural-parity exchange in the case of a transversely polarized target. The measured SDMEs are implemented into the rhoMC Monte Carlo generator, which is currently the only one capable of fully simulating the exclusive {rho}{sup 0} production and decay for both unpolarized and polarized beam and target. The interest in SDMEs for a polarized target arose after it was shown that at leading twist the corresponding SDMEs can be related to the azimuthal transverse target-spin asymmetry in the cross section of exclusive {rho}{sup 0} production which is sensitive to the unknown nucleon helicity-ip GPDs. Since the GPD formalism is only valid for longitudinally polarized vector mesons produced by longitudinal photons, for the first time the transverse target-spin asymmetry of longitudinally polarized {rho}{sup 0} mesons is extracted and compared to the available theoretical predictions, specically considering possible problems with next-to-leading order corrections. (orig.)

The rho-parameter in supersymmetric models

International Nuclear Information System (INIS)

Lim, C.S.; Inami, T.; Sakai, N.

1983-10-01

The electroweak rho-parameter is examined in a general class of supersymmetric models. Formulae are given for one-loop contributions to Δrho from scalar quarks and leptons, gauge-Higgs fermions and an extra doublet of Higgs scalars. Mass differences between members of isodoublet scalar quarks and leptons are constrained to be less than about 200 GeV. (author)

Effect of electroacupuncture on the mRNA and protein expression of Rho-A and Rho-associated kinase II in spinal cord injury rats

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You-jiang Min

2017-01-01

Full Text Available Electroacupuncture is beneficial for the recovery of spinal cord injury, but the underlying mechanism is unclear. The Rho/Rho-associated kinase (ROCK signaling pathway regulates the actin cytoskeleton by controlling the adhesive and migratory behaviors of cells that could inhibit neurite regrowth after neural injury and consequently hinder the recovery from spinal cord injury. Therefore, we hypothesized electroacupuncture could affect the Rho/ROCK signaling pathway to promote the recovery of spinal cord injury. In our experiments, the spinal cord injury in adult Sprague-Dawley rats was caused by an impact device. Those rats were subjected to electroacupuncture at Yaoyangguan (GV3, Dazhui (GV14, Zusanli (ST36 and Ciliao (BL32 and/or monosialoganglioside treatment. Behavioral scores revealed that the hindlimb motor functions improved with those treatments. Real-time quantitative polymerase chain reaction, fluorescence in situ hybridization and western blot assay showed that electroacupuncture suppressed the mRNA and protein expression of Rho-A and Rho-associated kinase II (ROCKII of injured spinal cord. Although monosialoganglioside promoted the recovery of hindlimb motor function, monosialoganglioside did not affect the expression of Rho-A and ROCKII. However, electroacupuncture combined with monosialoganglioside did not further improve the motor function or suppress the expression of Rho-A and ROCKII. Our data suggested that the electroacupuncture could specifically inhibit the activation of the Rho/ROCK signaling pathway thus partially contributing to the repair of injured spinal cord. Monosialoganglioside could promote the motor function but did not suppress expression of RhoA and ROCKII. There was no synergistic effect of electroacupuncture combined with monosialoganglioside.

UNC-73/trio RhoGEF-2 activity modulates Caenorhabditis elegans motility through changes in neurotransmitter signaling upstream of the GSA-1/Galphas pathway.

Science.gov (United States)

Hu, Shuang; Pawson, Tony; Steven, Robert M

2011-09-01

Rho-family GTPases play regulatory roles in many fundamental cellular processes. Caenorhabditis elegans UNC-73 RhoGEF isoforms function in axon guidance, cell migration, muscle arm extension, phagocytosis, and neurotransmission by activating either Rac or Rho GTPase subfamilies. Multiple differentially expressed UNC-73 isoforms contain a Rac-specific RhoGEF-1 domain, a Rho-specific RhoGEF-2 domain, or both domains. The UNC-73E RhoGEF-2 isoform is activated by the G-protein subunit Gαq and is required for normal rates of locomotion; however, mechanisms of UNC-73 and Rho pathway regulation of locomotion are not clear. To better define UNC-73 function in the regulation of motility we used cell-specific and inducible promoters to examine the temporal and spatial requirements of UNC-73 RhoGEF-2 isoform function in mutant rescue experiments. We found that UNC-73E acts within peptidergic neurons of mature animals to regulate locomotion rate. Although unc-73 RhoGEF-2 mutants have grossly normal synaptic morphology and weak resistance to the acetylcholinesterase inhibitor aldicarb, they are significantly hypersensitive to the acetylcholine receptor agonist levamisole, indicating alterations in acetylcholine neurotransmitter signaling. Consistent with peptidergic neuron function, unc-73 RhoGEF-2 mutants exhibit a decreased level of neuropeptide release from motor neuron dense core vesicles (DCVs). The unc-73 locomotory phenotype is similar to those of rab-2 and unc-31, genes with distinct roles in the DCV-mediated secretory pathway. We observed that constitutively active Gαs pathway mutations, which compensate for DCV-mediated signaling defects, rescue unc-73 RhoGEF-2 and rab-2 lethargic movement phenotypes. Together, these data suggest UNC-73 RhoGEF-2 isoforms are required for proper neurotransmitter signaling and may function in the DCV-mediated neuromodulatory regulation of locomotion rate.

gsub(ωrhoπ) coupling constant from QCD sum rules

International Nuclear Information System (INIS)

Eletsky, V.L.; Ioffe, B.L.; Kogan, Ya.I.

1982-01-01

QCD sum rules for the vertex function of two vector and one axial vector currents are used to calculate the gsub(ωrhoπ) coupling constant (where gsub(ωrhoπ) is a transition coupling constant for ω → rhoπ process). The obtained value, gsub(ωrhoπ) approximately 17 GeV -1 is in a good agreement with experimental data

Double spin asymmetry in exclusive $\\rho^0$ muoproduction at COMPASS

CERN Document Server

Alexakhin, V Yu; Alexandrov, Yu A; Alexeev, G D; Amoroso, A; Arbuzov, A; Badelek, B; Balestra, F; Ball, J; Baum, G; Barth, J; Bedfer, Y; Bernet, C; Bertini, R; Bettinelli, M; Birsa, R; Bisplinghoff, J; Bordalo, P; Bradamante, Franco; Bravar, A; Bressan, A; Brona, G; Burtin, E; Bussa, M P; Chapiro, A; Chiosso, M; Cicuttin, A; Colantoni, M L; Costa, S; Crespo, M L; D'Hose, N; Dalla Torre, S; Das, S; Das-Gupta, S S; De Masi, R; Dedek, N; Denisov, O Yu; Dhara, L; Díaz, V; Dinkelbach, A M; Donskov, S V; Dorofeev, V A; Doshita, N; Duic, V; Dünnweber, W; Eversheim, P D; Eyrich, W; Fabro, M; Faessler, M; Falaleev, V; Ferrero, A; Ferrero, L; Finger, M; Finger, M Jr; Fischer, H; Franco, C; Franz, J; Friedrich, J M; Frolov, V; Garfagnini, R; Gautheron, F; Gavrichtchouk, O P; Gazda, R; Gerassimov, S G; Geyer, R; Giorgi, M; Gobbo, B; Görtz, S; Gorin, A M; Grabmuller, S; Grajek, O A; Grasso, A; Grube, B; Gushterski, R; Guskov, A; Haas, F; Hannappel, J; Von Harrach, D; Hasegawa, T; Heckmann, J; Hedicke, S; Heinsius, F H; Hermann, R; Hess, C; Hinterberger, F; Von Hodenberg, M; Horikawa, N; Horikawa, S; Ilgner, C; Ioukaev, A I; Ishimoto, S; Ivanov, O; Ivanshin, Yu; Iwata, T; Jahn, R; Janata, A; Jasinski, P; Joosten, R; Jouravlev, N I; Kabuss, E M; Kang, D; Ketzer, B; Khaustov, G V; Khokhlov, Yu A; Kisselev, Yu; Klein, F; Klimaszewski, K; Koblitz, S; Koivuniemi, J H; Kolosov, V N; Komissarov, E V; Kondo, K; Knigsmann, K; Konorov, I; Konstantinov, V F; Korentchenko, A S; Korzenev, A; Kotzinian, A M; Koutchinski, N A; Kuznetsov, O; Kravchuk, N P; Kral, A; Kroumchtein, Z V; Kühn, R; Kunne, Fabienne; Kurek, K; Ladygin, M E; Lamanna, M; Le Goff, J M; Lednev, A A; Lehmann, A; Lichtenstadt, J; Liska, T; Ludwig, I; Maggiora, A; Maggiora, M; Magnon, A; Mallot, G K; Mann, A; Marchand, C; Marroncle, J; Martin, A; Marzec, J; Massmann, F; Matsuda, T; Maksimov, A N; Meyer, W; Mielech, A; Mikhailov, Yu V; Moinester, M A; Mutter, A; Nahle, O; Nagaytsev, A; Nagel, T; Nassalski, J P; Neliba, S; Nerling, F; Neubert, a S; Neyret, D P; Nikolaenko, V I; Nikolaev, K; Olshevskii, A G; Ostrick, M; Padee, A; Pagano, P; Panebianco, S; Panknin, R; Panzieri, D; Paul, S; Pawlukiewicz-Kaminska, B; Peshekhonov, V D; Piragino, G; Platchkov, S; Pochodzalla, J; Polak, J; Polyakov, V A; Pretz, J; Procureur, S; Quintans, C; Rajotte, J F; Rapatsky, V; Ramos, S; Reicherz, G; Richter, A; Robinet, F; Rocco, E; Rondio, E; Rozhdestvensky, A M; Ryabchikov, D I; Samoylenko, V D; Sandacz, A; Santos, H; Sapozhnikov, M G; Sarkar, S; Savin, I A; Schiavon, Paolo; Schill, C; Schmitt, L; Schonmeier, P; Schroder, W; Shevchenko, O Yu; Siebert, H W; Silva, L; Sinha, L; Sissakian, A N; Slunecka, M; Smirnov, G I; Sosio, S; Sozzi, F; Sugonyaev, V P; Srnka, A; Stinzing, F; Stolarski, M; Sulc, M; Sulej, R; Takabayashi, N; Tchalishev, V V; Tessaro, S; Tessarotto, F; Teufel, A; Tkatchev, L G; Venugopal, G; Virius, M; Vlassov, N V; Vossen, A; Webb, R; Weise, E; Weitzel, Q; Windmolders, R; Wirth, S; Wilicki, W; Zaremba, s K; Zavertyaev, M; Zemlyanichkina, E; Zhao, J; Ziegler, R; Zvyagin, A

2007-01-01

The longitudinal double spin asymmetry A_1^rho for exclusive leptoproduction of rho^0 mesons, mu + N -> mu + N + rho, is studied using the COMPASS 2002 and 2003 data. The measured reaction is incoherent exclusive rho^0 production on polarised deuterons. The Q^2 and x dependence of A_1^rho is presented in a wide kinematical range: 3x10^-3 < Q^2 < 7 (GeV/c)^2 and 5x10^-5 < x < 0.05. The presented results are the first measurements of A_1^rho at small Q2 (Q2 < 0.1 (GeV/c)^2) and small x (x < 3x10^-3). The asymmetry is in general compatible with zero in the whole kinematical range.

RhoG protein regulates platelet granule secretion and thrombus formation in mice.

Science.gov (United States)

Goggs, Robert; Harper, Matthew T; Pope, Robert J; Savage, Joshua S; Williams, Christopher M; Mundell, Stuart J; Heesom, Kate J; Bass, Mark; Mellor, Harry; Poole, Alastair W

2013-11-22

Rho GTPases such as Rac, RhoA, and Cdc42 are vital for normal platelet function, but the role of RhoG in platelets has not been studied. In other cells, RhoG orchestrates processes integral to platelet function, including actin cytoskeletal rearrangement and membrane trafficking. We therefore hypothesized that RhoG would play a critical role in platelets. Here, we show that RhoG is expressed in human and mouse platelets and is activated by both collagen-related peptide (CRP) and thrombin stimulation. We used RhoG(-/-) mice to study the function of RhoG in platelets. Integrin activation and aggregation were reduced in RhoG(-/-) platelets stimulated by CRP, but responses to thrombin were normal. The central defect in RhoG(-/-) platelets was reduced secretion from α-granules, dense granules, and lysosomes following CRP stimulation. The integrin activation and aggregation defects could be rescued by ADP co-stimulation, indicating that they are a consequence of diminished dense granule secretion. Defective dense granule secretion in RhoG(-/-) platelets limited recruitment of additional platelets to growing thrombi in flowing blood in vitro and translated into reduced thrombus formation in vivo. Interestingly, tail bleeding times were normal in RhoG(-/-) mice, suggesting that the functions of RhoG in platelets are particularly relevant to thrombotic disorders.

Partial contribution of Rho-kinase inhibition to the bioactivity of Ganoderma lingzhi and its isolated compounds: insights on discovery of natural Rho-kinase inhibitors.

Science.gov (United States)

Amen, Yhiya; Zhu, Qinchang; Tran, Hai-Bang; Afifi, Mohamed S; Halim, Ahmed F; Ashour, Ahmed; Shimizu, Kuniyoshi

2017-04-01

Recent studies identified Rho-kinase enzymes (ROCK-I and ROCK-II) as important targets that are involved in a variety of diseases. Synthetic Rho-kinase inhibitors have emerged as potential therapeutic agents to treat disorders such as hypertension, stroke, cancer, diabetes, glaucoma, etc. Our study is the first to screen the total ethanol extract of the medicinal mushroom Ganoderma lingzhi with thirty-five compounds for Rho-kinase inhibitory activity. Moreover, a molecular binding experiment was designed to investigate the binding affinity of the compounds at the active sites of Rho-kinase enzymes. The structure-activity relationship analysis was investigated. Our results suggest that the traditional uses of G. lingzhi might be in part due to the ROCK-I and ROCK-II inhibitory potential of this mushroom. Structure-activity relationship studies revealed some interesting features of the lanostane triterpenes that potentiate their Rho-kinase inhibition. These findings would be helpful for further studies on the design of Rho-kinase inhibitors from natural sources and open the door for contributions from other researchers for optimizing the development of natural Rho-kinase inhibitors.

Experiences and Coping Strategies of Host Families in International Youth Exchange

Science.gov (United States)

Weidemann, Arne; Bluml, Frances

2009-01-01

Twenty narrative interviews were conducted with German host parents between 2006 and 2007 about their experiences with a one-year stay of a guest student in their family. The study took place within the context of a student research project as part of the research-oriented MA course "Intercultural Communication-Intercultural Competence"…

Grb2 mediates semaphorin-4D-dependent RhoA inactivation.

Science.gov (United States)

Sun, Tianliang; Krishnan, Rameshkumar; Swiercz, Jakub M

2012-08-01

Signaling through the semaphorin 4D (Sema4D) receptor plexin-B1 is modulated by its interaction with tyrosine kinases ErbB-2 and Met. In cells expressing the plexin-B1-ErbB-2 receptor complex, ligand stimulation results in the activation of small GTPase RhoA and stimulation of cellular migration. By contrast, in cells expressing plexin-B1 and Met, ligand stimulation results in an association with the RhoGTPase-activating protein p190 RhoGAP and subsequent RhoA inactivation--a process that involves the tyrosine phosphorylation of plexin-B1 by Met. Inactivation of RhoA is necessary for Sema4D-mediated inhibition of cellular migration. It is, however, unknown how plexin-B1 phosphorylation regulates RhoGAP interaction and activity. Here we show that the activation of plexin-B1 by Sema4D and its subsequent tyrosine phosphorylation by Met creates a docking site for the SH2 domain of growth factor receptor bound-2 (Grb2). Grb2 is thereby recruited into the plexin-B1 receptor complex and, through its SH3 domain, interacts with p190 RhoGAP and mediates RhoA deactivation. Phosphorylation of plexin-B1 by Met and the recruitment of Grb2 have no effect on the R-RasGAP activity of plexin-B1, but are required for Sema4D-induced, RhoA-dependent antimigratory effects of Sema4D on breast cancer cells. These data show Grb2 as a direct link between plexin and p190-RhoGAP-mediated downstream signaling.

Pre-Steady State Kinetic Investigation of the Incorporation of Anti-Hepatitis B Nucleotide Analogs Catalyzed by Non-Canonical Human DNA Polymerases

Science.gov (United States)

Brown, Jessica A.; Pack, Lindsey R.; Fowler, Jason D.; Suo, Zucai

2011-01-01

Antiviral nucleoside analogs have been developed to inhibit the enzymatic activities of the hepatitis B virus (HBV) polymerase, thereby preventing the replication and production of HBV. However, the usage of these analogs can be limited by drug toxicity because the 5′-triphosphates of these nucleoside analogs (nucleotide analogs) are potential substrates for human DNA polymerases to incorporate into host DNA. Although they are poor substrates for human replicative DNA polymerases, it remains to be established whether these nucleotide analogs are substrates for the recently discovered human X- and Y-family DNA polymerases. Using pre-steady state kinetic techniques, we have measured the substrate specificity values for human DNA polymerases β, λ, η, ι, κ, and Rev1 incorporating the active forms of the following anti-HBV nucleoside analogs approved for clinical use: adefovir, tenofovir, lamivudine, telbivudine, and entecavir. Compared to the incorporation of a natural nucleotide, most of the nucleotide analogs were incorporated less efficiently (2 to >122,000) by the six human DNA polymerases. In addition, the potential for entecavir and telbivudine, two drugs which possess a 3′-hydroxyl, to become embedded into human DNA was examined by primer extension and DNA ligation assays. These results suggested that telbivudine functions as a chain terminator while entecavir was efficiently extended by the six enzymes and was a substrate for human DNA ligase I. Our findings suggested that incorporation of anti-HBV nucleotide analogs catalyzed by human X- and Y-family polymerases may contribute to clinical toxicity. PMID:22132702

Inhibition of Rho-associated kinases disturbs the collective cell migration of stratified TE-10 cells

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Taro Mikami

2015-01-01

Full Text Available BACKGROUND: The collective cell migration of stratified epithelial cells is considered to be an important phenomenon in wound healing, development, and cancer invasion; however, little is known about the mechanisms involved. Furthermore, whereas Rho family proteins, including RhoA, play important roles in cell migration, the exact role of Rho-associated coiled coil-containing protein kinases (ROCKs in cell migration is controversial and might be cell-type dependent. Here, we report the development of a novel modified scratch assay that was used to observe the collective cell migration of stratified TE-10 cells derived from a human esophageal cancer specimen. RESULTS: Desmosomes were found between the TE-10 cells and microvilli of the surface of the cell sheet. The leading edge of cells in the cell sheet formed a simple layer and moved forward regularly; these rows were followed by the stratified epithelium. ROCK inhibitors and ROCK small interfering RNAs (siRNAs disturbed not only the collective migration of the leading edge of this cell sheet, but also the stratified layer in the rear. In contrast, RhoA siRNA treatment resulted in more rapid migration of the leading rows and disturbed movement of the stratified portion. CONCLUSIONS: The data presented in this study suggest that ROCKs play an important role in mediating the collective migration of TE-10 cell sheets. In addition, differences between the effects of siRNAs targeting either RhoA or ROCKs suggested that distinct mechanisms regulate the collective cell migration in the simple epithelium of the wound edge versus the stratified layer of the epithelium.

etaγ decays of rho0, ω, and phi mesons

International Nuclear Information System (INIS)

Andrews, D.E.; Fukushima, Y.; Harvey, J.; Lobkowicz, F.; May, E.N.; Nelson, C.A. Jr.; Thorndike, E.H.

1977-01-01

etaγ decays of rho 0 , ω, and phi are studied. We find GAMMA (phi→etaγ) =55 +- 12 keV. Our data admit two solutions for (rho 0 , ω) →etaγ: Either GAMMA (rho 0 →etaγ) =50 +- 13 keV, GAMMA (ω→etaγ) =3.0 +2 /sup ./ 5 /sub -/ 1 /sub ./ 8 keV, and the (ω,rho) →etaγ relative decay phase is near zero; or GAMMA (rho 0 →etaγ) =76 +- 15 keV, GAMMA (ω→etaγ) =29 +- 7 keV, and the decay phase is near 180degree

The Role of NLR-related Protein 3 Inflammasome in Host Defense and Inflammatory Diseases

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Chul-Su Yang

2012-03-01

Full Text Available Among a number of innate receptors, the nucleotide-binding domain leucine-rich repeat containing (NLR nucleotide oligomerization domain (NOD-like receptor families are involved in the recognition of cytosolic pathogen- or danger-associated molecules. Activation of these specific sets of receptors leads to the assembly of a multiprotein complex, the inflammasome, leading to the activation of caspase-1 and maturation of the cytokines interleukin (IL-1β, IL-18, and IL-33. Among NLRs, NLR-related protein 3 (NLRP3 is one of the best-characterized receptors that activates the inflammasome. There is no doubt that NLRP3 inflammasome activation is important for host defense and effective pathogen clearance against fungal, bacterial, and viral infection. In addition, mounting evidence indicates that the NLRP3 inflammasome plays a role in a variety of inflammatory diseases, including gout, atherosclerosis, and type II diabetes, as well as under conditions of cellular stress or injury. Here, we review recent advances in our understanding of the role of the NLRP3 inflammasome in host defense and various inflammatory diseases.

UNC-73/Trio RhoGEF-2 Activity Modulates Caenorhabditis elegans Motility Through Changes in Neurotransmitter Signaling Upstream of the GSA-1/Gαs Pathway

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Hu, Shuang; Pawson, Tony; Steven, Robert M.

2011-01-01

Rho-family GTPases play regulatory roles in many fundamental cellular processes. Caenorhabditis elegans UNC-73 RhoGEF isoforms function in axon guidance, cell migration, muscle arm extension, phagocytosis, and neurotransmission by activating either Rac or Rho GTPase subfamilies. Multiple differentially expressed UNC-73 isoforms contain a Rac-specific RhoGEF-1 domain, a Rho-specific RhoGEF-2 domain, or both domains. The UNC-73E RhoGEF-2 isoform is activated by the G-protein subunit Gαq and is required for normal rates of locomotion; however, mechanisms of UNC-73 and Rho pathway regulation of locomotion are not clear. To better define UNC-73 function in the regulation of motility we used cell-specific and inducible promoters to examine the temporal and spatial requirements of UNC-73 RhoGEF-2 isoform function in mutant rescue experiments. We found that UNC-73E acts within peptidergic neurons of mature animals to regulate locomotion rate. Although unc-73 RhoGEF-2 mutants have grossly normal synaptic morphology and weak resistance to the acetylcholinesterase inhibitor aldicarb, they are significantly hypersensitive to the acetylcholine receptor agonist levamisole, indicating alterations in acetylcholine neurotransmitter signaling. Consistent with peptidergic neuron function, unc-73 RhoGEF-2 mutants exhibit a decreased level of neuropeptide release from motor neuron dense core vesicles (DCVs). The unc-73 locomotory phenotype is similar to those of rab-2 and unc-31, genes with distinct roles in the DCV-mediated secretory pathway. We observed that constitutively active Gαs pathway mutations, which compensate for DCV-mediated signaling defects, rescue unc-73 RhoGEF-2 and rab-2 lethargic movement phenotypes. Together, these data suggest UNC-73 RhoGEF-2 isoforms are required for proper neurotransmitter signaling and may function in the DCV-mediated neuromodulatory regulation of locomotion rate. PMID:21750262

Gene family expansions and contractions are associated with host range in plant pathogens of the genus Colletotrichum.

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Baroncelli, Riccardo; Amby, Daniel Buchvaldt; Zapparata, Antonio; Sarrocco, Sabrina; Vannacci, Giovanni; Le Floch, Gaétan; Harrison, Richard J; Holub, Eric; Sukno, Serenella A; Sreenivasaprasad, Surapareddy; Thon, Michael R

2016-08-05

Many species belonging to the genus Colletotrichum cause anthracnose disease on a wide range of plant species. In addition to their economic impact, the genus Colletotrichum is a useful model for the study of the evolution of host specificity, speciation and reproductive behaviors. Genome projects of Colletotrichum species have already opened a new era for studying the evolution of pathogenesis in fungi. We sequenced and annotated the genomes of four strains in the Colletotrichum acutatum species complex (CAsc), a clade of broad host range pathogens within the genus. The four CAsc proteomes and secretomes along with those representing an additional 13 species (six Colletotrichum spp. and seven other Sordariomycetes) were classified into protein families using a variety of tools. Hierarchical clustering of gene family and functional domain assignments, and phylogenetic analyses revealed lineage specific losses of carbohydrate-active enzymes (CAZymes) and proteases encoding genes in Colletotrichum species that have narrow host range as well as duplications of these families in the CAsc. We also found a lineage specific expansion of necrosis and ethylene-inducing peptide 1 (Nep1)-like protein (NLPs) families within the CAsc. This study illustrates the plasticity of Colletotrichum genomes, and shows that major changes in host range are associated with relatively recent changes in gene content.

Genome-Wide Identification of Cyclic Nucleotide-Gated Ion Channel Gene Family in Wheat and Functional Analyses of TaCNGC14 and TaCNGC16

Directory of Open Access Journals (Sweden)

Jia Guo

2018-01-01

Full Text Available Cyclic nucleotide gated channels (CNGCs play multifaceted roles in plants, particularly with respect to signaling processes associated with abiotic stress signaling and during host-pathogen interactions. Despite key roles during plant survival and response to environment, little is known about the activity and function of CNGC family in common wheat (Triticum aestivum L., a key stable food around the globe. In this study, we performed a genome-wide identification of CNGC family in wheat and identified a total 47 TaCNGCs in wheat, classifying these genes into four major groups (I–IV with two sub-groups (IVa and IVb. Sequence analysis revealed the presence of several conserved motifs, including a phosphate binding cassette (PBC and a “hinge” region, both of which have been hypothesized to be critical for the function of wheat CNGCs. During wheat infection with Pst, the transcript levels of TaCNGC14 and TaCNGC16, both members of group IVb, showed significant induction during a compatible interaction, while a reduction in gene expression was observed in incompatible interactions. In addition, TaCNGC14 and TaCNGC16 mRNA accumulation was significantly influenced by exogenously applied hormones, including abscisic acid (ABA, methyl jasmonate (MeJA, and salicylic acid (SA, suggesting a role in hormone signaling and/or perception. Silencing of TaCNGC14 and TaCNGC16 limited Pst growth and increased wheat resistance against Pst. The results presented herein contribute to our understanding of the wheat CNGC gene family and the mechanism of TaCNGCs signaling during wheat-Pst interaction.

1α,25-Dihydroxyvitamin D3 Ameliorates Seawater Aspiration-Induced Acute Lung Injury via NF-κB and RhoA/Rho Kinase Pathways

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Liu, Wei; Wang, Li; Luo, Ying; Li, Zhichao; Jin, Faguang

2014-01-01

Introduction Inflammation and pulmonary edema are involved in the pathogenesis of seawater aspiration-induced acute lung injury (ALI). Although several studies have reported that 1α,25-Dihydroxyvitamin D3 (calcitriol) suppresses inflammation, it has not been confirmed to be effective in seawater aspiration-induced ALI. Thus, we investigated the effect of calcitriol on seawater aspiration-induced ALI and explored the probable mechanism. Methods Male SD rats receiving different doses of calcitriol or not, underwent seawater instillation. Then lung samples were collected at 4 h for analysis. In addition, A549 cells and rat pulmonary microvascular endothelial cells (RPMVECs) were cultured with calcitriol or not and then stimulated with 25% seawater for 40 min. After these treatments, cells samples were collected for analysis. Results Results from real-time PCR showed that seawater stimulation up-regulated the expression of vitamin D receptor in lung tissues, A549 cells and RPMVECs. Seawater stimulation also activates NF-κB and RhoA/Rho kinase pathways. However, we found that pretreatment with calcitriol significantly inhibited the activation of NF-κB and RhoA/Rho kinase pathways. Meanwhile, treatment of calcitriol also improved lung histopathologic changes, reduced inflammation, lung edema and vascular leakage. Conclusions These results demonstrated that NF-κB and RhoA/Rho kinase pathways are critical in the development of lung inflammation and pulmonary edema and that treatment with calcitriol could ameliorate seawater aspiration-induced ALI, which was probably through the inhibition of NF-κB and RhoA/Rho kinase pathways. PMID:25118599

Differential recognition and hydrolysis of host carbohydrate antigens by Streptococcus pneumoniae family 98 glycoside hydrolases.

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Higgins, Melanie A; Whitworth, Garrett E; El Warry, Nahida; Randriantsoa, Mialy; Samain, Eric; Burke, Robert D; Vocadlo, David J; Boraston, Alisdair B

2009-09-18

The presence of a fucose utilization operon in the Streptococcus pneumoniae genome and its established importance in virulence indicates a reliance of this bacterium on the harvesting of host fucose-containing glycans. The identities of these glycans, however, and how they are harvested is presently unknown. The biochemical and high resolution x-ray crystallographic analysis of two family 98 glycoside hydrolases (GH98s) from distinctive forms of the fucose utilization operon that originate from different S. pneumoniae strains reveal that one enzyme, the predominant type among pneumococcal isolates, has a unique endo-beta-galactosidase activity on the LewisY antigen. Altered active site topography in the other species of GH98 enzyme tune its endo-beta-galactosidase activity to the blood group A and B antigens. Despite their different specificities, these enzymes, and by extension all family 98 glycoside hydrolases, use an inverting catalytic mechanism. Many bacterial and viral pathogens exploit host carbohydrate antigens for adherence as a precursor to colonization or infection. However, this is the first evidence of bacterial endoglycosidase enzymes that are known to play a role in virulence and are specific for distinct host carbohydrate antigens. The strain-specific distribution of two distinct types of GH98 enzymes further suggests that S. pneumoniae strains may specialize to exploit host-specific antigens that vary from host to host, a factor that may feature in whether a strain is capable of colonizing a host or establishing an invasive infection.

Hydrostatic pressure promotes the proliferation and osteogenic/chondrogenic differentiation of mesenchymal stem cells: The roles of RhoA and Rac1

Directory of Open Access Journals (Sweden)

Yin-Hua Zhao

2015-05-01

Full Text Available Our previous studies have shown that hydrostatic pressure can serve as an active regulator for bone marrow mesenchymal stem cells (BMSCs. The current work further investigates the roles of cytoskeletal regulatory proteins Ras homolog gene family member A (RhoA and Ras-related C3 botulinum toxin substrate 1 (Rac1 in hydrostatic pressure-related effects on BMSCs. Flow cytometry assays showed that the hydrostatic pressure promoted cell cycle initiation in a RhoA- and Rac1-dependent manner. Furthermore, fluorescence assays confirmed that RhoA played a positive and Rac1 displayed a negative role in the hydrostatic pressure-induced F-actin stress fiber assembly. Western blots suggested that RhoA and Rac1 play central roles in the pressure-inhibited ERK phosphorylation, and Rac1 but not RhoA was involved in the pressure-promoted JNK phosphorylation. Finally, real-time polymerase chain reaction (PCR experiments showed that pressure promoted the expression of osteogenic marker genes in BMSCs at an early stage of osteogenic differentiation through the up-regulation of RhoA activity. Additionally, the PCR results showed that pressure enhanced the expression of chondrogenic marker genes in BMSCs during chondrogenic differentiation via the up-regulation of Rac1 activity. Collectively, our results suggested that RhoA and Rac1 are critical to the pressure-induced proliferation and differentiation, the stress fiber assembly, and MAPK activation in BMSCs.

Hydrostatic pressure promotes the proliferation and osteogenic/chondrogenic differentiation of mesenchymal stem cells: The roles of RhoA and Rac1.

Science.gov (United States)

Zhao, Yin-Hua; Lv, Xin; Liu, Yan-Li; Zhao, Ying; Li, Qiang; Chen, Yong-Jin; Zhang, Min

2015-05-01

Our previous studies have shown that hydrostatic pressure can serve as an active regulator for bone marrow mesenchymal stem cells (BMSCs). The current work further investigates the roles of cytoskeletal regulatory proteins Ras homolog gene family member A (RhoA) and Ras-related C3 botulinum toxin substrate 1 (Rac1) in hydrostatic pressure-related effects on BMSCs. Flow cytometry assays showed that the hydrostatic pressure promoted cell cycle initiation in a RhoA- and Rac1-dependent manner. Furthermore, fluorescence assays confirmed that RhoA played a positive and Rac1 displayed a negative role in the hydrostatic pressure-induced F-actin stress fiber assembly. Western blots suggested that RhoA and Rac1 play central roles in the pressure-inhibited ERK phosphorylation, and Rac1 but not RhoA was involved in the pressure-promoted JNK phosphorylation. Finally, real-time polymerase chain reaction (PCR) experiments showed that pressure promoted the expression of osteogenic marker genes in BMSCs at an early stage of osteogenic differentiation through the up-regulation of RhoA activity. Additionally, the PCR results showed that pressure enhanced the expression of chondrogenic marker genes in BMSCs during chondrogenic differentiation via the up-regulation of Rac1 activity. Collectively, our results suggested that RhoA and Rac1 are critical to the pressure-induced proliferation and differentiation, the stress fiber assembly, and MAPK activation in BMSCs. Copyright © 2015. Published by Elsevier B.V.

Measurement of branching rates and search for CP violation in decays B0 {yields} {rho} {pi}, {rho} K; Mesure des rapports d'embranchement et recherche de la violation de CP dans les modes B{sup 0}{yields}rhopi, rhoK

Energy Technology Data Exchange (ETDEWEB)

Laplace, S

2003-04-01

The BABAR experiment, at the PEP-II collider at SLAC, has been studying since 1999 CP violation in the B meson system. After the precise measurement of sin(2*{beta}) we are now concentrating on measuring the alpha and gamma angles of the unitarity triangle. The work presented in this thesis concerns the measurement of the alpha angle in the B{sub 0} {yields} {rho}{pi} mode. We realized a time-dependant analysis of CP and the measurements of branching ratios concerning B{sub 0} {yields} {rho}{sup +-}{pi}{sup -+} and B{sub 0} {yields} {rho}{sup -}K{sup +} modes. The results obtained on an integrated luminosity of 80.9 fb{sup -1} are the following: B(B{sub 0} {yields} {rho}{sup +-}{pi}{sup -+}) = (22.6 {+-} 1.8 {+-} 2.2) 10{sup -6}, B(B{sub 0} {yields} {rho}{sup -}K{sup +}) (7.3 {+-} 1.3 {+-} 1.3) 10{sup -6}, ACP({rho}{pi}) = -0.18 {+-} 0.08 {+-} 0.03, ACP({rho}K) = -0.28 {+-} 0.17 {+-} 0.08, C({rho}{pi}) -0.36 {+-} 0.18 {+-} 0.04, S({rho}{pi}) = -0.19 {+-} 0.24 {+-} 0.03, {delta}C({rho}{pi}) = 0.28 {+-} 0.19 {+-} 0.04, {delta}S({rho}{pi}) = 0.15 {+-} 0.25 {+-} 0.03. We also measured the branching ratio of B{sub 0} {yields} {rho}{sub 0}{pi}{sub 0} with a significance of 2.7 {sigma}. We therefore put the following upper limit at 90% CL (confidence level): B(B{sub 0} {yields} {rho}{sub 0}{pi}{sub 0}) < 2.7*10{sup -6} at 90% CL. Finally, we built the heart of a complete Dalitz plot analysis of B{sub 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0}, and estimated the experimental sensibility on alpha. The results obtained on the B{sub 0} {yields} {rho}{pi} modes are interpreted in terms of constraints on the alpha angle with methods using SU(2) and SU(3) symmetries. We also measured the branching ratio of B{sub 0} {yields} {alpha}{sub 0}{pi} using a reduced luminosity, leading to the result: B(B{sub 0} {yields} {alpha}{sub 0}{pi}) = (6.2 +3.0-2.5 {+-} 1.1)*10{sup -6}. Some phenomenological studies have been performed to infer the feasibility of a CP analysis to determine the

RhoC a new target for therapeutic vaccination against metastatic cancer

DEFF Research Database (Denmark)

Wenandy, L.; Sorensen, R.B.; Straten, P.T.

2008-01-01

Most cancer deaths are due to the development of metastases. Increased expression of RhoC is linked to enhanced metastatic potential in multiple cancers. Consequently, the RhoC protein is an attractive target for drug design. The clinical application of immunotherapy against cancer is rapidly...... of cancer makes RhoC a very attractive target for anti-cancer immunotherapy. Herein, we describe an HLA-A3 restricted epitope from RhoC, which is recognized by cytotoxic T cells. Moreover, RhoC-specific T cells show cytotoxic potential against HLA-matched cancer cells of different origin. Thus, RhoC may...... moving forward in multiple areas, including the adoptive transfer of anti-tumor-reactive T cells and the use of "therapeutic" vaccines. The over-expression of RhoC in cancer and the fact that immune escape by down regulation or loss of expression of this protein would reduce the morbidity and mortality...

The ionizing radiation inducible gene PARX/ARAP2 participates in Rho and ARF signaling

International Nuclear Information System (INIS)

Wong, J.A.; Chen, Z.; Zhao, Y.; Vallis, K.A.; Marignani, P.A.; Randazzo, P.A.

2003-01-01

Full text: PARX/ARAP2 is a novel protein that we identified in a gene trap screen for ionizing radiation (IR)-regulated genes. It belongs to a recently described family of proteins that link Rho, ADP-ribosilation factor (ARF) and phosphoinositide 3-kinase (PI3-K) signaling. We have cloned the full length human PARX. Domain analysis of the predicted protein revealed a sterile-alpha motif, five pleckstrin homology domains, a RhoGTPase activating domain (RhoGAP) and an ARF activating domain (ARFGAP). PARX is early inducible by IR in a dose-dependent manner in murine ES cells and in several human B-cell lymphoma lines with up to six-fold induction at the mRNA level at 2 hours (10 Gy). Thus, the kinetics of PARX induction follows the pattern of the rapid response typical of many stress-induced immediate-early genes. PARX expression is also induced in response to other cellular stressors including sorbitol and bleomycin. PARX induction is dependent on PI3-K activity and can be suppressed by the PI3-K inhibitor LY294002. Induction of PARX in response to IR has been observed in cell lines that are p53 mutant indicating up-regulation independent of normal p53 function. The role of p53 in PARX induction is currently being studied using cell lines expressing temperature sensitive p53. Biochemical studies reveal that human PARX has in vivo RhoGAP activity for Rac1 and phosphatidylinositol 3,4,5-trisphosphate dependent ARFGAP activity for ARF1, ARF5 and ARF6. Also, temporal changes in PARX cellular localization following IR are currently being investigated using confocal microscopy. PARX is a gene with a potential role in the cellular response to genotoxic stress, and may illuminate the currently unclear role the small GTPases Rho and ARF play in the radiation response

Within- and among-family variation in parasite load and parasite-induced mortality in the land snail Arianta arbustorum, a host of parasitic mites.

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Schüpbach, Hans Ulrich; Baur, Bruno

2010-08-01

Variation in host susceptibility and parasite-induced mortality are preconditions for parasite-related selection on host populations. In terrestrial gastropods, variation in resistance against ectoparasite infection is poorly understood. We examined the within- and among-family variation in parasite load in full-siblings of the land snail Arianta arbustorum experimentally infected with Riccardoella limacum , a mite living in the mantle cavity of helicid land snails. We also quantified the influence of family origin and host size on parasite load and calculated its heritability (h(2)). Furthermore, we examined the influence of parasite load, snail size, and family origin on host winter mortality, an important life-history trait of A. arbustorum . Parasite load was heritable (h(2) = 0.63). In infected snails, parasite load was affected by family origin and increased with increasing shell size. Host mortality during hibernation increased with increasing parasite load and differed among families, but was not affected by snail size. Our results show high among-family variation both in resistance against ectoparasite infection and in host winter mortality. Furthermore, we show that parasite load is linked to snail size, which suggests that the proliferation of R. limacum is limited by resources provided by A. arbustorum .

Rho resonance parameters from lattice QCD

Energy Technology Data Exchange (ETDEWEB)

Guo, Dehua; Alexandru, Andrei; Molina, Raquel; Döring, Michael

2016-08-01

We perform a high-precision calculation of the phase shifts for $\\pi$-$\\pi$ scattering in the I = 1, J = 1 channel in the elastic region using elongated lattices with two mass-degenerate quark favors ($N_f = 2$). We extract the $\\rho$ resonance parameters using a Breit-Wigner fit at two different quark masses, corresponding to $m_{\\pi} = 226$MeV and $m_{\\pi} = 315$MeV, and perform an extrapolation to the physical point. The extrapolation is based on a unitarized chiral perturbation theory model that describes well the phase-shifts around the resonance for both quark masses. We find that the extrapolated value, $m_{\\rho} = 720(1)(15)$MeV, is significantly lower that the physical rho mass and we argue that this shift could be due to the absence of the strange quark in our calculation.

Coding sequence of human rho cDNAs clone 6 and clone 9

Energy Technology Data Exchange (ETDEWEB)

Chardin, P; Madaule, P; Tavitian, A

1988-03-25

The authors have isolated human cDNAs including the complete coding sequence for two rho proteins corresponding to the incomplete isolates previously described as clone 6 and clone 9. The deduced a.a. sequences, when compared to the a.a. sequence deduced from clone 12 cDNA, show that there are in human at least three highly homologous rho genes. They suggest that clone 12 be named rhoA, clone 6 : rhoB and clone 9 : rhoC. RhoA, B and C proteins display approx. 30% a.a. identity with ras proteins,. mainly clustered in four highly homologous internal regions corresponding to the GTP binding site; however at least one significant difference is found; the 3 rho proteins have an Alanine in position corresponding to ras Glycine 13, suggesting that rho and ras proteins might have slightly different biochemical properties.

Comparative Genomics of Rhodococcus equi Virulence Plasmids Indicates Host-Driven Evolution of the vap Pathogenicity Island.

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MacArthur, Iain; Anastasi, Elisa; Alvarez, Sonsiray; Scortti, Mariela; Vázquez-Boland, José A

2017-05-01

The conjugative virulence plasmid is a key component of the Rhodococcus equi accessory genome essential for pathogenesis. Three host-associated virulence plasmid types have been identified the equine pVAPA and porcine pVAPB circular variants, and the linear pVAPN found in bovine (ruminant) isolates. We recently characterized the R. equi pangenome (Anastasi E, et al. 2016. Pangenome and phylogenomic analysis of the pathogenic actinobacterium Rhodococcus equi. Genome Biol Evol. 8:3140-3148.) and we report here the comparative analysis of the virulence plasmid genomes. Plasmids within each host-associated type were highly similar despite their diverse origins. Variation was accounted for by scattered single nucleotide polymorphisms and short nucleotide indels, while larger indels-mostly in the plasticity region near the vap pathogencity island (PAI)-defined plasmid genomic subtypes. Only one of the plasmids analyzed, of pVAPN type, was exceptionally divergent due to accumulation of indels in the housekeeping backbone. Each host-associated plasmid type carried a unique PAI differing in vap gene complement, suggesting animal host-specific evolution of the vap multigene family. Complete conservation of the vap PAI was observed within each host-associated plasmid type. Both diversity of host-associated plasmid types and clonality of specific chromosomal-plasmid genomic type combinations were observed within the same R. equi phylogenomic subclade. Our data indicate that the overall strong conservation of the R. equi host-associated virulence plasmids is the combined result of host-driven selection, lateral transfer between strains, and geographical spread due to international livestock exchanges. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

{gamma}*{gamma}*->{rho}{rho} at very high energy

Energy Technology Data Exchange (ETDEWEB)

Pire, B. [CPhT, Ecole Polytechnique, 91128 Palaiseau, France, UMR 7644 du CNRS (France); Szymanowski, L. [Soltan Institute for Nuclear Studies, Hoza 69, 00-681 Warsaw (Poland) and Universite de Liege, B4000 Liege (Belgium); Wallon, S. [LPT, Universite d' Orsay, F 91405-Orsay (France); UMR 8627 du CNRS (France)

2005-06-13

The next generation of e{sup +}e{sup -}-colliders will offer a possibility of clean testing of QCD dynamics in the Regge limit. Recent progress in the theoretical description of exclusive processes permits for many of them a consistent use of the perturbative QCD methods. We advocate that the exclusive diffractive production of two {rho} mesons from virtual photons at very high energies should be measurable at the future linear collider (LC)

Rho-associated kinase is a therapeutic target in neuroblastoma.

Science.gov (United States)

Dyberg, Cecilia; Fransson, Susanne; Andonova, Teodora; Sveinbjörnsson, Baldur; Lännerholm-Palm, Jessika; Olsen, Thale K; Forsberg, David; Herlenius, Eric; Martinsson, Tommy; Brodin, Bertha; Kogner, Per; Johnsen, John Inge; Wickström, Malin

2017-08-08

Neuroblastoma is a peripheral neural system tumor that originates from the neural crest and is the most common and deadly tumor of infancy. Here we show that neuroblastoma harbors frequent mutations of genes controlling the Rac/Rho signaling cascade important for proper migration and differentiation of neural crest cells during neuritogenesis. RhoA is activated in tumors from neuroblastoma patients, and elevated expression of Rho-associated kinase (ROCK)2 is associated with poor patient survival. Pharmacological or genetic inhibition of ROCK1 and 2, key molecules in Rho signaling, resulted in neuroblastoma cell differentiation and inhibition of neuroblastoma cell growth, migration, and invasion. Molecularly, ROCK inhibition induced glycogen synthase kinase 3β-dependent phosphorylation and degradation of MYCN protein. Small-molecule inhibition of ROCK suppressed MYCN -driven neuroblastoma growth in TH- MYCN homozygous transgenic mice and MYCN gene-amplified neuroblastoma xenograft growth in nude mice. Interference with Rho/Rac signaling might offer therapeutic perspectives for high-risk neuroblastoma.

Rho GTPase activity modulates paramyxovirus fusion protein-mediated cell-cell fusion

International Nuclear Information System (INIS)

Schowalter, Rachel M.; Wurth, Mark A.; Aguilar, Hector C.; Lee, Benhur; Moncman, Carole L.; McCann, Richard O.; Dutch, Rebecca Ellis

2006-01-01

The paramyxovirus fusion protein (F) promotes fusion of the viral envelope with the plasma membrane of target cells as well as cell-cell fusion. The plasma membrane is closely associated with the actin cytoskeleton, but the role of actin dynamics in paramyxovirus F-mediated membrane fusion is unclear. We examined cell-cell fusion promoted by two different paramyxovirus F proteins in three cell types in the presence of constitutively active Rho family GTPases, major cellular coordinators of actin dynamics. Reporter gene and syncytia assays demonstrated that expression of either Rac1 V12 or Cdc42 V12 could increase cell-cell fusion promoted by the Hendra or SV5 glycoproteins, though the effect was dependent on the cell type expressing the viral glycoproteins. In contrast, RhoA L63 decreased cell-cell fusion promoted by Hendra glycoproteins but had little affect on SV5 F-mediated fusion. Also, data suggested that GTPase activation in the viral glycoprotein-containing cell was primarily responsible for changes in fusion. Additionally, we found that activated Cdc42 promoted nuclear rearrangement in syncytia

Quasi-two-dimensional Fermi-liquid state in Sr2RhO4-δ

International Nuclear Information System (INIS)

Nagai, Ichiro; Shirakawa, Naoki; Umeyama, Norio; Ikeda, Shin-ichi

2010-01-01

Single crystals of layered perovskite Sr 2 RhO 4-δ (δ=0.0 and 0.1) are successfully grown by the floating-zone method. Stoichiometric single crystals (Sr 2 RhO 4.0 ) are obtained by O 2 -annealing the as-grown crystals (Sr 2 RhO 3.9 ). Sr 2 RhO 4.0 and Sr 2 RhO 3.9 show quasi-two-dimensional Fermi-liquid behavior at low temperatures, whereas there are large differences in the anisotropy of electrical resistivity ρ c (3 K)/ρ ab (3 K) and Wilson ratio R w between Sr 2 RhO 4.0 and Sr 2 RhO 3.9 : ρ c (3 K)/ρ ab (3 K)=2400 (19000) and R w =3.8 (6.4) for Sr 2 RhO 4.0 (Sr 2 RhO 3.9 ). The differences observed between the temperature dependence of the in-plane electrical resistivity (T 2 RhO 4.0 and Sr 2 RhO 3.9 are mainly derived from those between the density of states and band structure near the corresponding Fermi level. This indicates that the changes in these physical properties, which are accompanied by oxygen defects in the Sr 2 RhO 4-δ system, can be explained by the rigid band model. Moreover, these results suggest that t 2g band-filling can be controlled by adjusting the oxygen defect content δ in the Sr 2 RhO 4-δ system. Although many similarities are observed in this study between the physical properties of Sr 2 RhO 4.0 and Sr 2 RuO 4 . Sr 2 RhO 4.0 does not exhibit superconductivity down to 36 mK. (author)

The activation of p38 MAPK primarily contributes to UV-induced RhoB expression by recruiting the c-Jun and p300 to the distal CCAAT box of the RhoB promoter

International Nuclear Information System (INIS)

Ahn, Jiwon; Choi, Jeong-Hae; Won, Misun; Kang, Chang-Mo; Gyun, Mi-Rang; Park, Hee-Moon; Kim, Chun-Ho; Chung, Kyung-Sook

2011-01-01

Highlights: → Regulation of transcriptional activation of RhoB is still unclear. → We examine the effect of p38 MAPK inhibition, and c-Jun and RhoB depletion on UV-induced RhoB expression and apoptosis. → We identify the regions of RhoB promoter necessary to confer UV responsiveness using pRhoB-luciferase reporter assays. → c-Jun, ATF2 and p300 are dominantly associated with NF-Y on the distal CCAAT box. → The activation of p38 MAPK primarily contribute to UV-induced RhoB expression by recruiting the c-Jun and p300 proteins on distal CCAAT box of RhoB promoter. -- Abstract: The Ras-related small GTP-binding protein RhoB is rapidly induced in response to genotoxic stresses caused by ionizing radiation. It is known that UV-induced RhoB expression results from the binding of activating transcription factor 2 (ATF2) via NF-Y to the inverted CCAAT box (-23) of the RhoB promoter. Here, we show that the association of c-Jun with the distal CCAAT box (-72) is primarily involved in UV-induced RhoB expression and p38 MAPK regulated RhoB induction through the distal CCAAT box. UV-induced RhoB expression and apoptosis were markedly attenuated by pretreatment with the p38 MAPK inhibitor. siRNA knockdown of RhoB, ATF2 and c-Jun resulted in decreased RhoB expression and eventually restored the growth of UV-irradiated Jurkat cells. In the reporter assay using luciferase under the RhoB promoter, inhibition of RhoB promoter activity by the p38 inhibitor and knockdown of c-Jun using siRNA occurred through the distal CCAAT box. Immunoprecipitation and DNA affinity protein binding assays revealed the association of c-Jun and p300 via NF-YA and the dissociation of histone deacetylase 1 (HDAC1) via c-Jun recruitment to the CCAAT boxes of the RhoB promoter. These results suggest that the activation of p38 MAPK primarily contributes to UV-induced RhoB expression by recruiting the c-Jun and p300 proteins to the distal CCAAT box of the RhoB promoter in Jurkat cells.

Activation of RhoA, but Not Rac1, Mediates Early Stages of S1P-Induced Endothelial Barrier Enhancement.

Science.gov (United States)

Zhang, Xun E; Adderley, Shaquria P; Breslin, Jerome W

2016-01-01

Compromised endothelial barrier function is a hallmark of inflammation. Rho family GTPases are critical in regulating endothelial barrier function, yet their precise roles, particularly in sphingosine-1-phosphate (S1P)-induced endothelial barrier enhancement, remain elusive. Confluent cultures of human umbilical vein endothelial cells (HUVEC) or human dermal microvascular endothelial cells (HDMEC) were used to model the endothelial barrier. Barrier function was assessed by determining the transendothelial electrical resistance (TER) using an electrical cell-substrate impedance sensor (ECIS). The roles of Rac1 and RhoA were tested in S1P-induced barrier enhancement. The results show that pharmacologic inhibition of Rac1 with Z62954982 failed to block S1P-induced barrier enhancement. Likewise, expression of a dominant negative form of Rac1, or knockdown of native Rac1 with siRNA, failed to block S1P-induced elevations in TER. In contrast, blockade of RhoA with the combination of the inhibitors Rhosin and Y16 significantly reduced S1P-induced increases in TER. Assessment of RhoA activation in real time using a fluorescence resonance energy transfer (FRET) biosensor showed that S1P increased RhoA activation primarily at the edges of cells, near junctions. This was complemented by myosin light chain-2 phosphorylation at cell edges, and increased F-actin and vinculin near intercellular junctions, which could all be blocked with pharmacologic inhibition of RhoA. The results suggest that S1P causes activation of RhoA at the cell periphery, stimulating local activation of the actin cytoskeleton and focal adhesions, and resulting in endothelial barrier enhancement. S1P-induced Rac1 activation, however, does not appear to have a significant role in this process.

Activation of RhoA, but Not Rac1, Mediates Early Stages of S1P-Induced Endothelial Barrier Enhancement.

Directory of Open Access Journals (Sweden)

Xun E Zhang

Full Text Available Compromised endothelial barrier function is a hallmark of inflammation. Rho family GTPases are critical in regulating endothelial barrier function, yet their precise roles, particularly in sphingosine-1-phosphate (S1P-induced endothelial barrier enhancement, remain elusive. Confluent cultures of human umbilical vein endothelial cells (HUVEC or human dermal microvascular endothelial cells (HDMEC were used to model the endothelial barrier. Barrier function was assessed by determining the transendothelial electrical resistance (TER using an electrical cell-substrate impedance sensor (ECIS. The roles of Rac1 and RhoA were tested in S1P-induced barrier enhancement. The results show that pharmacologic inhibition of Rac1 with Z62954982 failed to block S1P-induced barrier enhancement. Likewise, expression of a dominant negative form of Rac1, or knockdown of native Rac1 with siRNA, failed to block S1P-induced elevations in TER. In contrast, blockade of RhoA with the combination of the inhibitors Rhosin and Y16 significantly reduced S1P-induced increases in TER. Assessment of RhoA activation in real time using a fluorescence resonance energy transfer (FRET biosensor showed that S1P increased RhoA activation primarily at the edges of cells, near junctions. This was complemented by myosin light chain-2 phosphorylation at cell edges, and increased F-actin and vinculin near intercellular junctions, which could all be blocked with pharmacologic inhibition of RhoA. The results suggest that S1P causes activation of RhoA at the cell periphery, stimulating local activation of the actin cytoskeleton and focal adhesions, and resulting in endothelial barrier enhancement. S1P-induced Rac1 activation, however, does not appear to have a significant role in this process.

A global phylogeny of leafmining Ectoedemia moths (Lepidoptera: Nepticulidae): exploring host plant family shifts and allopatry as drivers of speciation.

Science.gov (United States)

Doorenweerd, Camiel; van Nieukerken, Erik J; Menken, Steph B J

2015-01-01

Host association patterns in Ectoedemia (Lepidoptera: Nepticulidae) are also encountered in other insect groups with intimate plant relationships, including a high degree of monophagy, a preference for ecologically dominant plant families (e.g. Fagaceae, Rosaceae, Salicaceae, and Betulaceae) and a tendency for related insect species to feed on related host plant species. The evolutionary processes underlying these patterns are only partly understood, we therefore assessed the role of allopatry and host plant family shifts in speciation within Ectoedemia. Six nuclear and mitochondrial DNA markers with a total aligned length of 3692 base pairs were used to infer phylogenetic relationships among 92 species belonging to the subgenus Ectoedemia of the genus Ectoedemia, representing a thorough taxon sampling with a global coverage. The results support monophyletic species groups that are congruent with published findings based on morphology. We used the obtained phylogeny to explore host plant family association and geographical distribution to investigate if host shifts and allopatry have been instrumental in the speciation of these leafmining insects. We found that, even though most species within species groups commonly feed on plants from one family, shifts to a distantly related host family have occasionally occurred throughout the phylogeny and such shifts are most commonly observed towards Betulaceae. The largest radiations have occurred within species groups that feed on Fagaceae, Rosaceae, and Salicaceae. Most species are restricted to one of the seven global biogeographic regions, but within species groups representatives are commonly found in different biogeographic regions. Although we find general patterns with regard to host use and biogeography, there are differences between clades that suggest that different drivers of speciation, and perhaps drivers that we did not examine, have shaped diversity patterns in different clades.

QCD Factorizations in Exclusive {gamma}*{gamma}*{yields}{rho}{sub L}{sup 0}{rho}{sub L}{sup 0}

Energy Technology Data Exchange (ETDEWEB)

Pire, B. [CPHT, Ecole Polytechnique, CNRS, Palaiseau (France); Segond, M. [LPTHE, Universite Paris 6 and 7, CNRS, Paris (France); LPT, Universite Paris-Sud, CNRS, Orsay (France); Szymanowski, L. [CPHT, Ecole Polytechnique, CNRS, Palaiseau (France); SINS, Warsaw (Poland); Wallon, S. [LPT, Universite Paris-Sud, CNRS, Orsay (France)

2008-11-15

The exclusive process e{sup +}e{sup -}{yields}e{sup +}e{sup -}{rho}{sub L}{sup 0}{rho}{sub L}{sup 0} allows to study various dynamics and factorization properties of perturbative QCD. At moderate energy, we demonstrate how collinearQCD factorization emerges, involving either generalized distribution amplitudes (GDA) or transition distribution amplitudes (TDA). At higher energies, in the Regge limit of QCD, we show that it offers a promising probe of the BFKL resummation effects to be studied at ILC.

Regulation of cerebral cortex development by Rho GTPases: insights from in vivo studies

Directory of Open Access Journals (Sweden)

Roberta eAzzarelli

2015-01-01

Full Text Available The cerebral cortex is the site of higher human cognitive and motor functions. Histologically, it is organized into six horizontal layers, each containing unique populations of molecularly and functionally distinct excitatory projection neurons and inhibitory interneurons. The stereotyped cellular distribution of cortical neurons is crucial for the formation of functional neural circuits and it is predominantly established during embryonic development. Cortical neuron development is a multiphasic process characterized by sequential steps of neural progenitor proliferation, cell cycle exit, neuroblast migration and neuronal differentiation. This series of events requires an extensive and dynamic remodeling of the cell cytoskeleton at each step of the process. As major regulators of the cytoskeleton, the family of small Rho GTPases has been shown to play essential functions in cerebral cortex development. Here we review in vivo findings that support the contribution of Rho GTPases to cortical projection neuron development and we address their involvement in the etiology of cerebral cortex malformations.

RhoA GTPase regulates radiation-induced alterations in endothelial cell adhesion and migration

International Nuclear Information System (INIS)

Rousseau, Matthieu; Gaugler, Marie-Hélène; Rodallec, Audrey; Bonnaud, Stéphanie; Paris, François; Corre, Isabelle

2011-01-01

Highlights: ► We explore the role of RhoA in endothelial cell response to ionizing radiation. ► RhoA is rapidly activated by single high-dose of radiation. ► Radiation leads to RhoA/ROCK-dependent actin cytoskeleton remodeling. ► Radiation-induced apoptosis does not require the RhoA/ROCK pathway. ► Radiation-induced alteration of endothelial adhesion and migration requires RhoA/ROCK. -- Abstract: Endothelial cells of the microvasculature are major target of ionizing radiation, responsible of the radiation-induced vascular early dysfunctions. Molecular signaling pathways involved in endothelial responses to ionizing radiation, despite being increasingly investigated, still need precise characterization. Small GTPase RhoA and its effector ROCK are crucial signaling molecules involved in many endothelial cellular functions. Recent studies identified implication of RhoA/ROCK in radiation-induced increase in endothelial permeability but other endothelial functions altered by radiation might also require RhoA proteins. Human microvascular endothelial cells HMEC-1, either treated with Y-27632 (inhibitor of ROCK) or invalidated for RhoA by RNA interference were exposed to 15 Gy. We showed a rapid radiation-induced activation of RhoA, leading to a deep reorganisation of actin cytoskeleton with rapid formation of stress fibers. Endothelial early apoptosis induced by ionizing radiation was not affected by Y-27632 pre-treatment or RhoA depletion. Endothelial adhesion to fibronectin and formation of focal adhesions increased in response to radiation in a RhoA/ROCK-dependent manner. Consistent with its pro-adhesive role, ionizing radiation also decreased endothelial cells migration and RhoA was required for this inhibition. These results highlight the role of RhoA GTPase in ionizing radiation-induced deregulation of essential endothelial functions linked to actin cytoskeleton.

Cooperation of Rho family proteins Rac1 and Cdc42 in cartilage development and calcified tissue formation.

Science.gov (United States)

Ikehata, Mikiko; Yamada, Atsushi; Fujita, Koji; Yoshida, Yuko; Kato, Tadashi; Sakashita, Akiko; Ogata, Hiroaki; Iijima, Takehiko; Kuroda, Masahiko; Chikazu, Daichi; Kamijo, Ryutaro

2018-04-20

Rac1 and Cdc42, Rho family low molecular weight G proteins, are intracellular signaling factors that transmit various information from outside to inside cells. Primarily, they are known to control various biological activities mediated by actin cytoskeleton reorganization, such as cell proliferation, differentiation, and apoptosis. In order to investigate the functions of Rac1 and Cdc42 in bone formation, we prepared cartilage-specific double conditional knockout mice, Rac1 fl/fl ; Cdc42 fl/fl ; Col2-Cre (Rac1: Cdc42 dcKO mice), which died just after birth, similar to Cdc42 fl/fl ; Col2-Cre mice (Cdc42 cKO mice). Our findings showed that the long tubule bone in Rac1: Cdc42 dcKO mice was shorter than that in Rac1 fl/fl ; Col2-Cre mice (Rac1 cKO mice) and Cdc42 cKO mice. Abnormal skeleton formation was also observed and disordered columnar formation in the growth plate of the Rac1: Cdc42 dcKO mice was more severe as compared to the Rac1 cKO and Cdc42 cKO mice. Together, these results suggest that Rac1 and Cdc42 have cooperating roles in regulation of bone development. Copyright © 2018 Elsevier Inc. All rights reserved.

An adventitious interaction of filamin A with RhoGDI2(Tyr153Glu)

International Nuclear Information System (INIS)

Song, Mia; He, Qianjing; Berk, Benjamin-Andreas; Hartwig, John H.; Stossel, Thomas P.; Nakamura, Fumihiko

2016-01-01

Filamin A (FLNA) is an actin filament crosslinking protein with multiple intracellular binding partners. Mechanical force exposes cryptic FLNA binding sites for some of these ligands. To identify new force-dependent binding interactions, we used a fusion construct composed of two FLNA domains, one of which was previously identified as containing a force-dependent binding site as a bait in a yeast two-hybrid system and identified the Rho dissociation inhibitor 2 (RhoGDI2) as a potential interacting partner. A RhoGDI2 truncate with 81 N-terminal amino acid residues and a phosphomimetic mutant, RhoGDI(Tyr153Glu) interacted with the FLNA construct. However, neither wild-type or full-length RhoGDI2 phosphorylated at Y153 interacted with FLNA. Our interpretation of these contradictions is that truncation and/or mutation of RhoGDI2 perturbs its conformation to expose a site that adventitiously binds FLNA and is not a bona–fide interaction. Therefore, previous studies reporting that a RhoGDI(Y153E) mutant suppresses the metastasis of human bladder cancer cells must be reinvestigated in light of artificial interaction of this point mutant with FLNA. - Highlights: • RhoGDI2 is identified as a potential filamin A (FLNA)-binding partner. • Phosphomimetic mutant, RhoGDI2(Tyr153Glu) interacts with FLNA. • RhoGDI2 phosphorylated (Tyr153) by src kinase does not interact with FLNA. • Mutation of Tyr-153 to Glu of RhoGDI2 does not mimic phosphorylation. • RhoGDI2(Tyr153Glu) provokes an adventitious interaction with FLNA.

An adventitious interaction of filamin A with RhoGDI2(Tyr153Glu)

Energy Technology Data Exchange (ETDEWEB)

Song, Mia; He, Qianjing [Hematology Division, Department of Medicine, Brigham and Women' s Hospital, Harvard Medical School, Boston MA (United States); Berk, Benjamin-Andreas [Faculty of Veterinary Medicine and Faculty of Biosciences and Pharmacy, University of Leipzig, Leipzig (Germany); Hartwig, John H.; Stossel, Thomas P. [Hematology Division, Department of Medicine, Brigham and Women' s Hospital, Harvard Medical School, Boston MA (United States); Nakamura, Fumihiko, E-mail: fnakamura@partners.org [Hematology Division, Department of Medicine, Brigham and Women' s Hospital, Harvard Medical School, Boston MA (United States)

2016-01-15

Filamin A (FLNA) is an actin filament crosslinking protein with multiple intracellular binding partners. Mechanical force exposes cryptic FLNA binding sites for some of these ligands. To identify new force-dependent binding interactions, we used a fusion construct composed of two FLNA domains, one of which was previously identified as containing a force-dependent binding site as a bait in a yeast two-hybrid system and identified the Rho dissociation inhibitor 2 (RhoGDI2) as a potential interacting partner. A RhoGDI2 truncate with 81 N-terminal amino acid residues and a phosphomimetic mutant, RhoGDI(Tyr153Glu) interacted with the FLNA construct. However, neither wild-type or full-length RhoGDI2 phosphorylated at Y153 interacted with FLNA. Our interpretation of these contradictions is that truncation and/or mutation of RhoGDI2 perturbs its conformation to expose a site that adventitiously binds FLNA and is not a bona–fide interaction. Therefore, previous studies reporting that a RhoGDI(Y153E) mutant suppresses the metastasis of human bladder cancer cells must be reinvestigated in light of artificial interaction of this point mutant with FLNA. - Highlights: • RhoGDI2 is identified as a potential filamin A (FLNA)-binding partner. • Phosphomimetic mutant, RhoGDI2(Tyr153Glu) interacts with FLNA. • RhoGDI2 phosphorylated (Tyr153) by src kinase does not interact with FLNA. • Mutation of Tyr-153 to Glu of RhoGDI2 does not mimic phosphorylation. • RhoGDI2(Tyr153Glu) provokes an adventitious interaction with FLNA.

Ameloblasts require active RhoA to generate normal dental enamel.

Science.gov (United States)

Xue, Hui; Li, Yong; Everett, Eric T; Ryan, Kathleen; Peng, Li; Porecha, Rakhee; Yan, Yan; Lucchese, Anna M; Kuehl, Melissa A; Pugach, Megan K; Bouchard, Jessica; Gibson, Carolyn W

2013-08-01

RhoA plays a fundamental role in regulation of the actin cytoskeleton, intercellular attachment, and cell proliferation. During amelogenesis, ameloblasts (which produce the enamel proteins) undergo dramatic cytoskeletal changes and the RhoA protein level is up-regulated. Transgenic mice were generated that express a dominant-negative RhoA transgene in ameloblasts using amelogenin gene-regulatory sequences. Transgenic and wild-type (WT) molar tooth germs were incubated with sodium fluoride (NaF) or sodium chloride (NaCl) in organ culture. Filamentous actin (F-actin) stained with phalloidin was elevated significantly in WT ameloblasts treated with NaF compared with WT ameloblasts treated with NaCl or with transgenic ameloblasts treated with NaF, thereby confirming a block in the RhoA/Rho-associated protein kinase (ROCK) pathway in the transgenic mice. Little difference in quantitative fluorescence (an estimation of fluorosis) was observed between WT and transgenic incisors from mice provided with drinking water containing NaF. We subsequently found reduced transgene expression in incisors compared with molars. Transgenic molar teeth had reduced amelogenin, E-cadherin, and Ki67 compared with WT molar teeth. Hypoplastic enamel in transgenic mice correlates with reduced expression of the enamel protein, amelogenin, and E-cadherin and cell proliferation are regulated by RhoA in other tissues. Together these findings reveal deficits in molar ameloblast function when RhoA activity is inhibited. © 2013 Eur J Oral Sci.

Lifetime of rho meson in correlation with magnetic-dimensional reduction

Energy Technology Data Exchange (ETDEWEB)

Kawaguchi, Mamiya [Nagoya University, Department of Physics, Nagoya (Japan); Matsuzaki, Shinya [Nagoya University, Department of Physics, Nagoya (Japan); Nagoya University, Institute for Advanced Research, Nagoya (Japan)

2017-04-15

It is naively expected that in a strong magnetic configuration, the Landau quantization ceases the neutral rho meson to decay to the charged pion pair, so the neutral rho meson will be long-lived. To closely access this naive observation, we explicitly compute the charged pion loop in the magnetic field at the one-loop level, to evaluate the magnetic dependence of the lifetime for the neutral rho meson as well as its mass. Due to the dimensional reduction induced by the magnetic field (violation of the Lorentz invariance), the polarization (spin s{sub z} = 0, ±1) modes of the rho meson, as well as the corresponding pole mass and width, are decomposed in a nontrivial manner compared to the vacuum case. To see the significance of the reduction effect, we simply take the lowest Landau level approximation to analyze the spin-dependent rho masses and widths. We find that the ''fate'' of the rho meson may be more complicated because of the magnetic-dimensional reduction: as the magnetic field increases, the rho width for the spin s{sub z} = 0 starts to develop, reaches a peak, then vanishes at the critical magnetic field to which the folklore refers. On the other side, the decay rates of the other rhos for s{sub z} = ±1 monotonically increase as the magnetic field develops. The correlation between the polarization dependence and the Landau level truncation is also addressed. (orig.)

Identification of a novel BRCA1 nucleotide 4803delCC/c.4684delCC mutation and a nucleotide 249T>A/c.130T>A (p.Cys44Ser) mutation in two Greenlandic Inuit families

DEFF Research Database (Denmark)

Hansen, Thomas van Overeem; Jønson, Lars; Albrechtsen, Anders

2010-01-01

Germ-line mutations in the tumour suppressor proteins BRCA1 and BRCA2 predispose to breast and ovarian cancer. We have recently identified a Greenlandic Inuit BRCA1 nucleotide 234T>G/c.115T>G (p.Cys39Gly) founder mutation, which at that time was the only disease-causing BRCA1/BRCA2 mutation...... identified in this population. Here, we describe the identification of a novel disease-causing BRCA1 nucleotide 4803delCC/c.4684delCC mutation in a Greenlandic Inuit with ovarian cancer. The mutation introduces a frameshift and a premature stop at codon 1572. We have also identified a BRCA1 nucleotide 249T......>A/c.130T>A (p.Cys44Ser) mutation in another Greenlandic individual with ovarian cancer. This patient share a 1-2 Mb genomic fragment, containing the BRCA1 gene, with four Danish families harbouring the same mutation, suggesting that the 249T>A/c.130T>A (p.Cys44Ser) mutation originates from a Danish...

A Gene Family Coding for Salivary Proteins (SHOT) of the Polyphagous Spider Mite Tetranychus urticae Exhibits Fast Host-Dependent Transcriptional Plasticity.

Science.gov (United States)

Jonckheere, Wim; Dermauw, Wannes; Khalighi, Mousaalreza; Pavlidi, Nena; Reubens, Wim; Baggerman, Geert; Tirry, Luc; Menschaert, Gerben; Kant, Merijn R; Vanholme, Bartel; Van Leeuwen, Thomas

2018-01-01

The salivary protein repertoire released by the herbivorous pest Tetranychus urticae is assumed to hold keys to its success on diverse crops. We report on a spider mite-specific protein family that is expanded in T. urticae. The encoding genes have an expression pattern restricted to the anterior podocephalic glands, while peptide fragments were found in the T. urticae secretome, supporting the salivary nature of these proteins. As peptide fragments were identified in a host-dependent manner, we designated this family as the SHOT (secreted host-responsive protein of Tetranychidae) family. The proteins were divided in three groups based on sequence similarity. Unlike TuSHOT3 genes, TuSHOT1 and TuSHOT2 genes were highly expressed when feeding on a subset of family Fabaceae, while expression was depleted on other hosts. TuSHOT1 and TuSHOT2 expression was induced within 24 h after certain host transfers, pointing toward transcriptional plasticity rather than selection as the cause. Transfer from an 'inducer' to a 'noninducer' plant was associated with slow yet strong downregulation of TuSHOT1 and TuSHOT2, occurring over generations rather than hours. This asymmetric on and off regulation points toward host-specific effects of SHOT proteins, which is further supported by the diversity of SHOT genes identified in Tetranychidae with a distinct host repertoire.

Purification and crystallization of the catalytic PRONE domain of RopGEF8 and its complex with Rop4 from Arabidopsis thaliana

International Nuclear Information System (INIS)

Thomas, Christoph; Weyand, Michael; Wittinghofer, Alfred; Berken, Antje

2006-01-01

Crystals of the catalytic PRONE domain of the guanine nucleotide exchange factor RopGEF8 and its complex with the Rho-family protein Rop4 from A. thaliana were obtained that diffract to 2.2 and 3.1 Å resolution, respectively. The PRONE domain of the guanine nucleotide exchange factor RopGEF8 (PRONE8) was purified and crystallized free and in complex with the Rho-family protein Rop4 using the hanging-drop vapour-diffusion method. PRONE8 crystals were obtained using NaCl as precipitating agent and belong to the hexagonal space group P6 5 22. Native and anomalous data sets were collected using synchrotron radiation at 100 K to 2.2 and 2.8 Å resolution, respectively. Crystals of the Rop4–PRONE8 complex belonging to space group P6 3 were obtained using Tacsimate and PEG 3350 as precipitating agents and diffracted to 3.1 Å resolution

Purification and crystallization of the catalytic PRONE domain of RopGEF8 and its complex with Rop4 from Arabidopsis thaliana

Energy Technology Data Exchange (ETDEWEB)

Thomas, Christoph; Weyand, Michael; Wittinghofer, Alfred; Berken, Antje, E-mail: antje.berken@mpi-dortmund.mpg.de [Department of Structural Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund (Germany)

2006-06-01

Crystals of the catalytic PRONE domain of the guanine nucleotide exchange factor RopGEF8 and its complex with the Rho-family protein Rop4 from A. thaliana were obtained that diffract to 2.2 and 3.1 Å resolution, respectively. The PRONE domain of the guanine nucleotide exchange factor RopGEF8 (PRONE8) was purified and crystallized free and in complex with the Rho-family protein Rop4 using the hanging-drop vapour-diffusion method. PRONE8 crystals were obtained using NaCl as precipitating agent and belong to the hexagonal space group P6{sub 5}22. Native and anomalous data sets were collected using synchrotron radiation at 100 K to 2.2 and 2.8 Å resolution, respectively. Crystals of the Rop4–PRONE8 complex belonging to space group P6{sub 3} were obtained using Tacsimate and PEG 3350 as precipitating agents and diffracted to 3.1 Å resolution.

Basal and Activated Calcium Sensitization Mediated by RhoA/Rho Kinase Pathway in Rats with Genetic and Salt Hypertension

Czech Academy of Sciences Publication Activity Database

Behuliak, Michal; Bencze, Michal; Vaněčková, Ivana; Kuneš, Jaroslav; Zicha, Josef

2017-01-01

Roč. 2017, January (2017), č. článku 8029728. ISSN 2314-6133 R&D Projects: GA ČR(CZ) GP14-16225P; GA MZd(CZ) NV15-25396A Institutional support: RVO:67985823 Keywords : calcium sensitization * RhoA/Rho kinase * fasudil * calcium influx * nifedipine * BAY K8644 Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery OBOR OECD: Cardiac and Cardiovascular systems Impact factor: 2.476, year: 2016

Problems with rho R measurements: what are the ways out

International Nuclear Information System (INIS)

Pan, Y.L.; Larsen, J.T.

1977-01-01

An important scaling parameter or figure of merit in inertially-confined fusion is the maximum fuel rho R achieved by the target--rho is the density, and R the radius of the fuel. Every technique used, thus far, in laser-initiated-fusion-microexplosion experiments to obtain this data had major deficiencies. We examine critically the merits of the various possible methods of measuring fuel rho R and their ranges of applicability

RhoA mediates the expression of acidic extracellular pH-induced matrix metalloproteinase-9 mRNA through phospholipase D1 in mouse metastatic B16-BL6 melanoma cells.

Science.gov (United States)

Maeda, Toyonobu; Yuzawa, Satoshi; Suzuki, Atsuko; Baba, Yuh; Nishimura, Yukio; Kato, Yasumasa

2016-03-01

Solid tumors are characterized by acidic extracellular pH (pHe). The present study examined the contribution of small GTP-binding proteins to phospholipase D (PLD) activation of acidic pHe-induced matrix metalloproteinase-9 (MMP-9) production. Acidic pHe-induced MMP-9 production was reduced by C3 exoenzyme, which inhibits the Rho family of GTPases; cytochalasin D, which inhibits actin reorganization; and simvastatin, which inhibits geranylgeranylation of Rho. Small interfering RNA (siRNA) against RhoA, but not against Rac1 or Cdc42, significantly inhibited acidic pHe induction of MMP-9. Pull-down assays showed that acidic pHe increased the activated form of RhoA. Forced expression of constitutively active RhoA induced MMP-9 production, even at neutral pHe. RhoA siRNA also reduced acidic pHe induced PLD activity. Specific inhibition of PLD1 and Pld1 gene knockout significantly reduced acidic pHe-induced MMP-9 expression. In contrast, PLD2 inhibition or knockout had no effect on MMP-9 expression. These findings suggested that RhoA-PLD1 signaling is involved in acidic pHe induction of MMP-9.

Tentative of observation of the {rho}{sup +} {yields} {pi}{sup +} + {gamma} decay mode; Tentative de mise en evidence du mode de desintegration {rho}{sup +} {yields} {pi}{sup +} + {gamma}

Energy Technology Data Exchange (ETDEWEB)

Daudin, A.; Jabiol, M.A.; Kochowski, C.; Lewin, C.; Rogozinski, A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Mongelli, S.; Romano, A.; Waloschek, P. [Istituto di Fisica dell' Universita, Bari (Italy)

1964-07-01

One of the purposes of the 1.6 GeV/c {pi}{sup +} p experiment, carried out in the 50 cm Saclay hydrogen bubble chamber, was to observe the {rho}{sup +} {yields} {pi}{sup +} {gamma} radiative decay mode in {pi}{sup +} p {yields} {pi}{sup +} p {gamma} interactions. A 6 mm thick lead plate, set at the outgoing part of the chamber, was used to convert {gamma} into e{sup +} e{sup -}. Among the {gamma} observed arising directly from the investigated interactions, no event originates from a {pi}{sup +} {gamma} compound in the region of {rho}{sup +}. This gives an upper limit of 2 per cent for the branching ratio ({rho}{sup +} {yields} {pi}{sup +} {gamma}) / ({rho}{sup +} {yields} {pi}{sup +} {gamma} + {rho}{sup +} {yields} {pi}{sup +} {pi}{sup 0}). (authors) [French] Une experience, dont l'un des buts etait de mettre en evidence le mode de desintegration radiatif du {rho}{sup +} en {pi}{sup +} {gamma} dans les interactions {pi}{sup +} p {yields} p {pi}{sup +} {gamma} a 1,6 GeV/c, a ete effectuee a l'aide de la chambre a bulles a hydrogene liquide de 50 cm de diametre de Saclay. Une plaque de plomb de 6 mm d'epaisseur, servant de convertisseur {gamma} {yields} e{sup +} e{sup -} a ete placee au sein du liquide a la sortie de la chambre. Parmi les y observes issus directement de l'interaction etudiee, aucun ne provient d'un complexe {pi}{sup +} {gamma} ayant la masse du {rho}{sup +}, ce qui fixe la limite superieure du rapport de branchement ({rho}{sup +} {yields} {pi}{sup +} {gamma}) / ({rho}{sup +} {yields} {pi}{sup +} {gamma} + {rho}{sup +} {yields} {pi}{sup +} {pi}{sup 0}) a 2 pour cent. (auteurs)

Characterization of RhoC Expression in Benign and Malignant Breast Disease

Science.gov (United States)

Kleer, Celina G.; van Golen, Kenneth L.; Zhang, Yanhong; Wu, Zhi-Fen; Rubin, Mark A.; Merajver, Sofia D.

2002-01-01

The most important factor in predicting outcome in patients with early breast cancer is the stage of the disease. There is no robust marker capable of identifying invasive carcinomas that despite their small size have a high metastatic potential, and that would benefit from more aggressive treatment. RhoC-GTPase is a member of the Ras-superfamily and is involved in cell polarity and motility. We hypothesized that RhoC expression would be a good marker to identify breast cancer patients with high risk of developing metastases, and that it would be a prognostic marker useful in the clinic. We developed a specific anti-RhoC antibody and studied archival breast tissues that comprise a broad spectrum of breast disease. One hundred eighty-two specimens from 164 patients were used. Immunohistochemistry was performed on formalin-fixed tissues. Staining intensity was graded 0 to 3+ (0 to 1+ was considered negative and 2 to 3+ was considered positive). RhoC was not expressed in any of the normal, fibrocystic changes, atypical hyperplasia, or ductal carcinoma in situ, but was expressed in 36 of 118 invasive carcinomas and strongly correlated with tumor stage (P = 0.01). RhoC had high specificity (88%) in detecting invasive carcinomas with metastatic potential. Of the invasive carcinomas smaller than 1 cm, RhoC was highly specific in detecting tumors that developed metastases. RhoC expression was associated with negative progesterone receptor and HER-2/neu overexpression. We characterized RhoC expression in human breast tissues. RhoC is specifically expressed in invasive breast carcinomas capable of metastasizing, and it may be clinically useful in patients with tumors smaller than 1 cm to guide treatment. PMID:11839578

Dual transcriptomics of virus-host interactions: comparing two Pacific oyster families presenting contrasted susceptibility to ostreid herpesvirus 1.

Science.gov (United States)

Segarra, Amélie; Mauduit, Florian; Faury, Nicole; Trancart, Suzanne; Dégremont, Lionel; Tourbiez, Delphine; Haffner, Philippe; Barbosa-Solomieu, Valérie; Pépin, Jean-François; Travers, Marie-Agnès; Renault, Tristan

2014-07-09

Massive mortality outbreaks affecting Pacific oyster (Crassostrea gigas) spat in various countries have been associated with the detection of a herpesvirus called ostreid herpesvirus type 1 (OsHV-1). However, few studies have been performed to understand and follow viral gene expression, as it has been done in vertebrate herpesviruses. In this work, experimental infection trials of C. gigas spat with OsHV-1 were conducted in order to test the susceptibility of several bi-parental oyster families to this virus and to analyze host-pathogen interactions using in vivo transcriptomic approaches. The divergent response of these oyster families in terms of mortality confirmed that susceptibility to OsHV-1 infection has a significant genetic component. Two families with contrasted survival rates were selected. A total of 39 viral genes and five host genes were monitored by real-time PCR. Initial results provided information on (i) the virus cycle of OsHV-1 based on the kinetics of viral DNA replication and transcription and (ii) host defense mechanisms against the virus. In the two selected families, the detected amounts of viral DNA and RNA were significantly different. This result suggests that Pacific oysters are genetically diverse in terms of their susceptibility to OsHV-1 infection. This contrasted susceptibility was associated with dissimilar host gene expression profiles. Moreover, the present study showed a positive correlation between viral DNA amounts and the level of expression of selected oyster genes.

Implementation of Pollard Rho attack on elliptic curve cryptography over binary fields

Science.gov (United States)

Wienardo, Yuliawan, Fajar; Muchtadi-Alamsyah, Intan; Rahardjo, Budi

2015-09-01

Elliptic Curve Cryptography (ECC) is a public key cryptosystem with a security level determined by discrete logarithm problem called Elliptic Curve Discrete Logarithm Problem (ECDLP). John M. Pollard proposed an algorithm for discrete logarithm problem based on Monte Carlo method and known as Pollard Rho algorithm. The best current brute-force attack for ECC is Pollard Rho algorithm. In this research we implement modified Pollard Rho algorithm on ECC over GF (241). As the result, the runtime of Pollard Rho algorithm increases exponentially with the increase of the ECC key length. This work also presents the estimated runtime of Pollard Rho attack on ECC over longer bits.

Assessment of response to beta-blockers by expression of βArr2 and RhoA/ROCK2 in antrum mucosa in cirrhotic patients

DEFF Research Database (Denmark)

Trebicka, Jonel; von Heydebrand, Matthias; Lehmann, Jennifer

2016-01-01

BACKGROUND & AIMS: Non-selective beta-blockers (NSBB) are first choice for prevention of variceal bleeding. But possible deleterious effects in refractory ascites and frequent non-response are clinical drawbacks. Since levels of vasoactive proteins in antrum mucosa reflect vascular dysfunction...... and protein expression of Ras homolog family member A (RhoA), Rho-kinase (ROCK)2, beta-arrestin2 (βArr2), endothelial nitric oxide synthase (eNOS) and the phosphorylation of downstream effectors VASP and moesin were analyzed using PCR and Western blot. Further 21 patients on NSBB were evaluated...

Inelastic photoproduction of ω and rho+-mesons

International Nuclear Information System (INIS)

Nelson, C.A. Jr.; May, E.N.; Abramson, J.; Andrews, D.E.; Harvey, J.; Lobkowicz, F.; Singer, M.N.; Thorndike, E.H.; Nordberg, M.E. Jr.

1978-01-01

We report measurements of inelastic photoproduction of ω and rho +- mesons from hydrogen and deuterium at incident photon energies in the range 7.5-10.5 GeV. For ωΔ and rho - Δ ++ production differential cross sections dsigma/dt' and spin density matrices are presented. For higher missing masses the cross sections dsigma/dM/sub X/ 2 and invariant structure functions F(x) are also given. The data are compared to a one-pion-exchange model. We conclude that pion exchange is dominant for inelastic ω photoproduction, but unimportant for rho +- during annealing, even though the resistively determined transport scattering time increased by a factor of 7.8 during annealing. Orbital depairing was found to follow a relation zeta = zeta 0 + αH 2 and to increase with annealing in a manner expected from the change in mean free path determined from measurements of H/sub cnu/

RhoA is dispensable for skin development, but crucial for contraction and directed migration of keratinocytes

DEFF Research Database (Denmark)

Jackson, Ben; Peyrollier, Karine; Pedersen, Esben

2011-01-01

RhoA is a small guanosine-5'-triphosphatase (GTPase) suggested to be essential for cytokinesis, stress fiber formation, and epithelial cell-cell contacts. In skin, loss of RhoA was suggested to underlie pemphigus skin blistering. To analyze RhoA function in vivo, we generated mice with a keratino......RhoA is a small guanosine-5'-triphosphatase (GTPase) suggested to be essential for cytokinesis, stress fiber formation, and epithelial cell-cell contacts. In skin, loss of RhoA was suggested to underlie pemphigus skin blistering. To analyze RhoA function in vivo, we generated mice......-cell contacts. Furthermore we observed increased cell spreading due to impaired RhoA-ROCK (Rho-associated protein kinase)-MLC phosphatase-MLC-mediated cell contraction, independent of Rac1. Rho-inhibiting toxins further increased multinucleation of RhoA-null cells but had no significant effect on spreading......, suggesting that RhoB and RhoC have partially overlapping functions with RhoA. Loss of RhoA decreased directed cell migration in vitro caused by reduced migration speed and directional persistence. These defects were not related to the decreased cell contraction and were independent of ROCK, as ROCK...

Born order study of {gamma}{sup *}{gamma}{sup *} {yields} {rho}{rho} at very high energy

Energy Technology Data Exchange (ETDEWEB)

Pire, B. [Ecole Polytechnique, 91 - Palaiseau (France). Centre de Physique Theorique; Szymanowski, L. [Soltan Institute for Nuclear Studies, Warsaw (Poland); Liege Univ. (Belgium); Wallon, S. [Paris-11 Univ., Lab. de Physique Theorique, 91 - Orsay (France)

2005-07-01

We calculate the cross-section for the diffractive exclusive process {gamma}{sub L}{sup *}(Q{sub 1}{sup 2}){gamma}{sub L}{sup *}(Q{sub 2}{sup 2}) {yields} {rho}{sub L}{sup 0}{rho}{sub L}{sup 0}, in view of its study in the future high energy e{sup +}e{sup -} linear collider. The Born order approximation of the amplitude is completely calculable in the hard region Q{sub 1}{sup 2},Q{sub 2}{sup 2} >> {lambda}{sup 2}(QCD). The resulting cross-section is large enough for this process to be measurable with foreseen luminosity and energy, for Q{sub 1}{sup 2} and Q{sub 2}{sup 2} in the range of a few GeV{sup 2}. (authors)

Problem-Solving Test: The Mechanism of Transcription Termination by the Rho Factor

Science.gov (United States)

Szeberenyi, Jozsef

2012-01-01

Transcription termination comes in two forms in "E. coli" cells. Rho-dependent termination requires the binding of a termination protein called Rho factor to the transcriptional machinery at the terminator region, whereas Rho-independent termination is achieved by conformational changes in the transcript itself. This article presents a test…

T1rho mapping of entire femoral cartilage using depth- and angle-dependent analysis

International Nuclear Information System (INIS)

Nozaki, Taiki; Kaneko, Yasuhito; Yu, Hon J.; Yoshioka, Hiroshi; Kaneshiro, Kayleigh; Schwarzkopf, Ran; Hara, Takeshi

2016-01-01

To create and evaluate normalized T1rho profiles of the entire femoral cartilage in healthy subjects with three-dimensional (3D) angle- and depth-dependent analysis. T1rho images of the knee from 20 healthy volunteers were acquired on a 3.0-T unit. Cartilage segmentation of the entire femur was performed slice-by-slice by a board-certified radiologist. The T1rho depth/angle-dependent profile was investigated by partitioning cartilage into superficial and deep layers, and angular segmentation in increments of 4 over the length of segmented cartilage. Average T1rho values were calculated with normalized T1rho profiles. Surface maps and 3D graphs were created. T1rho profiles have regional and depth variations, with no significant magic angle effect. Average T1rho values in the superficial layer of the femoral cartilage were higher than those in the deep layer in most locations (p < 0.05). T1rho values in the deep layer of the weight-bearing portions of the medial and lateral condyles were lower than those of the corresponding non-weight-bearing portions (p < 0.05). Surface maps and 3D graphs demonstrated that cartilage T1rho values were not homogeneous over the entire femur. Normalized T1rho profiles from the entire femoral cartilage will be useful for diagnosing local or early T1rho abnormalities and osteoarthritis in clinical applications. (orig.)

T1rho mapping of entire femoral cartilage using depth- and angle-dependent analysis

Energy Technology Data Exchange (ETDEWEB)

Nozaki, Taiki; Kaneko, Yasuhito; Yu, Hon J.; Yoshioka, Hiroshi [University of California Irvine, Department of Radiological Sciences, Orange, CA (United States); Kaneshiro, Kayleigh [University of California Irvine, School of Medicine, Irvine, CA (United States); Schwarzkopf, Ran [University of California Irvine, Department of Orthopedic Surgery, Irvine, CA (United States); Hara, Takeshi [Gifu University Graduate School of Medicine, Department of Intelligent Image Information, Division of Regeneration and Advanced Medical Sciences, Gifu (Japan)

2016-06-15

To create and evaluate normalized T1rho profiles of the entire femoral cartilage in healthy subjects with three-dimensional (3D) angle- and depth-dependent analysis. T1rho images of the knee from 20 healthy volunteers were acquired on a 3.0-T unit. Cartilage segmentation of the entire femur was performed slice-by-slice by a board-certified radiologist. The T1rho depth/angle-dependent profile was investigated by partitioning cartilage into superficial and deep layers, and angular segmentation in increments of 4 over the length of segmented cartilage. Average T1rho values were calculated with normalized T1rho profiles. Surface maps and 3D graphs were created. T1rho profiles have regional and depth variations, with no significant magic angle effect. Average T1rho values in the superficial layer of the femoral cartilage were higher than those in the deep layer in most locations (p < 0.05). T1rho values in the deep layer of the weight-bearing portions of the medial and lateral condyles were lower than those of the corresponding non-weight-bearing portions (p < 0.05). Surface maps and 3D graphs demonstrated that cartilage T1rho values were not homogeneous over the entire femur. Normalized T1rho profiles from the entire femoral cartilage will be useful for diagnosing local or early T1rho abnormalities and osteoarthritis in clinical applications. (orig.)

Simvastatin induces apoptosis by a Rho-dependent mechanism in cultured cardiac fibroblasts and myofibroblasts

International Nuclear Information System (INIS)

Copaja, Miguel; Venegas, Daniel; Aranguiz, Pablo; Canales, Jimena; Vivar, Raul; Catalan, Mabel; Olmedo, Ivonne; Rodriguez, Andrea E.; Chiong, Mario; Leyton, Lisette; Lavandero, Sergio; Diaz-Araya, Guillermo

2011-01-01

Several clinical trials have shown the beneficial effects of statins in the prevention of coronary heart disease. Additionally, statins promote apoptosis in vascular smooth muscle cells, in renal tubular epithelial cells and also in a variety of cell lines; yet, the effects of statins on cardiac fibroblast and myofibroblast, primarily responsible for cardiac tissue healing are almost unknown. Here, we investigated the effects of simvastatin on cardiac fibroblast and myofibroblast viability and studied the molecular cell death mechanism triggered by simvastatin in both cell types. Methods: Rat neonatal cardiac fibroblasts and myofibroblasts were treated with simvastatin (0.1-10 μM) up to 72 h. Cell viability and apoptosis were evaluated by trypan blue exclusion method and by flow cytometry, respectively. Caspase-3 activation and Rho protein levels and activity were also determined by Western blot and pull-down assay, respectively. Results: Simvastatin induces caspase-dependent apoptosis of cardiac fibroblasts and myofibroblasts in a concentration- and time-dependent manner, with greater effects on fibroblasts than myofibroblasts. These effects were prevented by mevalonate, farnesylpyrophosphate and geranylgeranylpyrophosphate, but not squalene. These last results suggest that apoptosis was dependent on small GTPases of the Rho family rather than Ras. Conclusion: Simvastatin triggered apoptosis of cardiac fibroblasts and myofibroblasts by a mechanism independent of cholesterol synthesis, but dependent of isoprenilation of Rho protein. Additionally, cardiac fibroblasts were more susceptible to simvastatin-induced apoptosis than cardiac myofibroblasts. Thus simvastatin could avoid adverse cardiac remodeling leading to a less fibrotic repair of the damaged tissues. - Research Highlights: → Simvastatin decreases CF and CMF viability independent of cholesterol synthesis. → Simvastatin induces CF and CMF apoptosis in a caspase-dependent manner being CMF more resistant

Diacylglycerol kinase ζ regulates RhoA activation via a kinase-independent scaffolding mechanism

DEFF Research Database (Denmark)

Ard, Ryan; Mulatz, Kirk; Abramovici, Hanan

2012-01-01

, but the underlying mechanisms are unclear. Diacylglycerol kinase ζ (DGKζ), which phosphorylates diacylglycerol to yield phosphatidic acid, selectively dissociates Rac1 by stimulating PAK1-mediated phosphorylation of RhoGDI on Ser-101/174. Similarly, phosphorylation of RhoGDI on Ser-34 by protein kinase Cα (PKCα......GDI and was required for efficient interaction of PKCα and RhoA. DGKζ-null fibroblasts had condensed F-actin bundles and altered focal adhesion distribution, indicative of aberrant RhoA signaling. Two targets of the RhoA effector ROCK showed reduced phosphorylation in DGKζ-null cells. Collectively our findings suggest...

Poxvirus Host Range Genes and Virus-Host Spectrum: A Critical Review.

Science.gov (United States)

Oliveira, Graziele Pereira; Rodrigues, Rodrigo Araújo Lima; Lima, Maurício Teixeira; Drumond, Betânia Paiva; Abrahão, Jônatas Santos

2017-11-07

The Poxviridae family is comprised of double-stranded DNA viruses belonging to nucleocytoplasmic large DNA viruses (NCLDV). Among the NCLDV, poxviruses exhibit the widest known host range, which is likely observed because this viral family has been more heavily investigated. However, relative to each member of the Poxviridae family, the spectrum of the host is variable, where certain viruses can infect a large range of hosts, while others are restricted to only one host species. It has been suggested that the variability in host spectrum among poxviruses is linked with the presence or absence of some host range genes. Would it be possible to extrapolate the restriction of viral replication in a specific cell lineage to an animal, a far more complex organism? In this study, we compare and discuss the relationship between the host range of poxvirus species and the abundance/diversity of host range genes. We analyzed the sequences of 38 previously identified and putative homologs of poxvirus host range genes, and updated these data with deposited sequences of new poxvirus genomes. Overall, the term host range genes might not be the most appropriate for these genes, since no correlation between them and the viruses' host spectrum was observed, and a change in nomenclature should be considered. Finally, we analyzed the evolutionary history of these genes, and reaffirmed the occurrence of horizontal gene transfer (HGT) for certain elements, as previously suggested. Considering the data presented in this study, it is not possible to associate the diversity of host range factors with the amount of hosts of known poxviruses, and this traditional nomenclature creates misunderstandings.

Poxvirus Host Range Genes and Virus–Host Spectrum: A Critical Review

Science.gov (United States)

Oliveira, Graziele Pereira; Rodrigues, Rodrigo Araújo Lima; Lima, Maurício Teixeira; Drumond, Betânia Paiva; Abrahão, Jônatas Santos

2017-01-01

The Poxviridae family is comprised of double-stranded DNA viruses belonging to nucleocytoplasmic large DNA viruses (NCLDV). Among the NCLDV, poxviruses exhibit the widest known host range, which is likely observed because this viral family has been more heavily investigated. However, relative to each member of the Poxviridae family, the spectrum of the host is variable, where certain viruses can infect a large range of hosts, while others are restricted to only one host species. It has been suggested that the variability in host spectrum among poxviruses is linked with the presence or absence of some host range genes. Would it be possible to extrapolate the restriction of viral replication in a specific cell lineage to an animal, a far more complex organism? In this study, we compare and discuss the relationship between the host range of poxvirus species and the abundance/diversity of host range genes. We analyzed the sequences of 38 previously identified and putative homologs of poxvirus host range genes, and updated these data with deposited sequences of new poxvirus genomes. Overall, the term host range genes might not be the most appropriate for these genes, since no correlation between them and the viruses’ host spectrum was observed, and a change in nomenclature should be considered. Finally, we analyzed the evolutionary history of these genes, and reaffirmed the occurrence of horizontal gene transfer (HGT) for certain elements, as previously suggested. Considering the data presented in this study, it is not possible to associate the diversity of host range factors with the amount of hosts of known poxviruses, and this traditional nomenclature creates misunderstandings. PMID:29112165

Dipole moments of the rho meson

International Nuclear Information System (INIS)

Hecht, M.B.; McKellar, B.H.P.

1997-04-01

The electric and magnetic dipole moments (EDM) of the rho meson are calculated using the propagators and vertices derived from the quantum chromodynamics Dyson-Schwinger equations. Results obtained from using the Bethe-Salpeter amplitude studied by Chappell, Mitchell et. al., and Pichowsky and Lee, are compared. The rho meson EDM is generated through the inclusion of a quark electric dipole moment, which is left as a free variable. These results are compared to the perturbative results to obtain a measure of the effects of quark interactions and confinement. The two dipole moments are also calculated using the phenomenological MIT bag model to provide a further basis for comparison

The Role of Interleukin-1 Family Members in the Host Defence Against Aspergillus fumigatus

NARCIS (Netherlands)

Gresnigt, M.S.; Veerdonk, F.L. van de

2014-01-01

The interleukin (IL)-1 family consists of 11 members, which all play significant roles in regulating inflammatory responses in the host. IL-1alpha and IL-1beta exert potent pro-inflammatory effects and are key players in the recruitment of neutrophils to the site of inflammation. Protective

Small-Molecule Inhibition of Rho/MKL/SRF Transcription in Prostate Cancer Cells: Modulation of Cell Cycle, ER Stress, and Metastasis Gene Networks

Directory of Open Access Journals (Sweden)

Chris R. Evelyn

2016-05-01

Full Text Available Metastasis is the major cause of cancer deaths and control of gene transcription has emerged as a critical contributing factor. RhoA- and RhoC-induced gene transcription via the actin-regulated transcriptional co-activator megakaryocytic leukemia (MKL and serum response factor (SRF drive metastasis in breast cancer and melanoma. We recently identified a compound, CCG-1423, which blocks Rho/MKL/SRF-mediated transcription and inhibits PC-3 prostate cancer cell invasion. Here, we undertook a genome-wide expression study in PC-3 cells to explore the mechanism and function of this compound. There was significant overlap in the genes modulated by CCG-1423 and Latrunculin B (Lat B, which blocks the Rho/MKL/SRF pathway by preventing actin polymerization. In contrast, the general transcription inhibitor 5,6-dichloro-1-β-d-ribofuranosyl-1H-benzimidazole (DRB showed a markedly different pattern. Effects of CCG-1423 and Lat B on gene expression correlated with literature studies of MKL knock-down. Gene sets involved in DNA synthesis and repair, G1/S transition, and apoptosis were modulated by CCG-1423. It also upregulated genes involved in endoplasmic reticulum stress. Targets of the known Rho target transcription factor family E2F and genes related to melanoma progression and metastasis were strongly suppressed by CCG-1423. These results confirm the ability of our compound to inhibit expression of numerous Rho/MKL-dependent genes and show effects on stress pathways as well. This suggests a novel approach to targeting aggressive cancers and metastasis.

Horizontal gene transfer and nucleotide compositional anomaly in large DNA viruses

Directory of Open Access Journals (Sweden)

Ogata Hiroyuki

2007-12-01

Full Text Available Abstract Background DNA viruses have a wide range of genome sizes (5 kb up to 1.2 Mb, compared to 0.16 Mb to 1.5 Mb for obligate parasitic bacteria that do not correlate with their virulence or the taxonomic distribution of their hosts. The reasons for such large variation are unclear. According to the traditional view of viruses as gifted "gene pickpockets", large viral genome sizes could originate from numerous gene acquisitions from their hosts. We investigated this hypothesis by studying 67 large DNA viruses with genome sizes larger than 150 kb, including the recently characterized giant mimivirus. Given that horizontally transferred DNA often have anomalous nucleotide compositions differing from the rest of the genome, we conducted a detailed analysis of the inter- and intra-genome compositional properties of these viruses. We then interpreted their compositional heterogeneity in terms of possible causes, including strand asymmetry, gene function/expression, and horizontal transfer. Results We first show that the global nucleotide composition and nucleotide word usage of viral genomes are species-specific and distinct from those of their hosts. Next, we identified compositionally anomalous (cA genes in viral genomes, using a method based on Bayesian inference. The proportion of cA genes is highly variable across viruses and does not exhibit a significant correlation with genome size. The vast majority of the cA genes were of unknown function, lacking homologs in the databases. For genes with known homologs, we found a substantial enrichment of cA genes in specific functional classes for some of the viruses. No significant association was found between cA genes and compositional strand asymmetry. A possible exogenous origin for a small fraction of the cA genes could be confirmed by phylogenetic reconstruction. Conclusion At odds with the traditional dogma, our results argue against frequent genetic transfers to large DNA viruses from their

Complete nucleotide sequence and genome organization of Olive latent virus 3, a new putative member of the family Tymoviridae.

Science.gov (United States)

Alabdullah, Abdulkader; Minafra, Angelantonio; Elbeaino, Toufic; Saponari, Maria; Savino, Vito; Martelli, Giovanni P

2010-09-01

The complete nucleotide sequence and the genome organization were determined of a putative new member of the family Tymoviridae, tentatively named Olive latent virus 3 (OLV-3), recovered in southern Italy from a symptomless olive tree. The sequenced ssRNA genome comprises 7148 nucleotides excluding the poly(A) tail and contains four open reading frames (ORFs). ORF1 encodes a polyprotein of 221.6kDa in size, containing the conserved signatures of the methyltransferase (MTR), papain-like protease (PRO), helicase (HEL) and RNA-dependent RNA polymerase (RdRp) domains of the replication-associated proteins of positive-strand RNA viruses. ORF2 overlaps completely ORF1 and encodes a putative protein of 43.33kDa showing limited sequence similarity with the putative movement protein of Maize rayado fino virus (MRFV). ORF3 codes for a protein with predicted molecular mass of 28.46kDa, identified as the coat protein (CP), whereas ORF4 overlaps ORF3 and encodes a putative protein of 16kDa with sequence similarity to the p16 and p31 proteins of Citrus sudden death-associated virus (CSDaV) and Grapevine fleck virus (GFkV), respectively. Within the family Tymoviridae, OLV-3 genome has the closest identity level (49-52%) with members of the genus Marafivirus, from which, however, it differs because of the diverse genome organization and the presence of a single type of CP subunits. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Protein prenylation: a new mode of host-pathogen interaction.

Science.gov (United States)

Amaya, Moushimi; Baranova, Ancha; van Hoek, Monique L

2011-12-09

Post translational modifications are required for proteins to be fully functional. The three step process, prenylation, leads to farnesylation or geranylgeranylation, which increase the hydrophobicity of the prenylated protein for efficient anchoring into plasma membranes and/or organellar membranes. Prenylated proteins function in a number of signaling and regulatory pathways that are responsible for basic cell operations. Well characterized prenylated proteins include Ras, Rac and Rho. Recently, pathogenic prokaryotic proteins, such as SifA and AnkB, have been shown to be prenylated by eukaryotic host cell machinery, but their functions remain elusive. The identification of other bacterial proteins undergoing this type of host-directed post-translational modification shows promise in elucidating host-pathogen interactions to develop new therapeutics. This review incorporates new advances in the study of protein prenylation into a broader aspect of biology with a focus on host-pathogen interaction. Copyright © 2011 Elsevier Inc. All rights reserved.

Mechanisms of RhoGDI2 Mediated Lung Cancer Epithelial-Mesenchymal Transition Suppression

Directory of Open Access Journals (Sweden)

Huiyan Niu

2014-11-01

Full Text Available Background: The aim of this study was to evaluate the function of RhoGDI2 in lung cancer epithelial-mesenchymal transition (EMT process and to illustrate the underlying mechanisms that will lead to improvement of lung cancer treatment. Methods: The RhoGDI2 knock-down and overexpressing A549 cell lines were first constructed. The influence of RhoGDI2 on cytoskeleton in A549 cells was studied using two approaches: G-LISA-based Rac1 activity measurement and immunostaining-based F-actin distribution. The expression levels of key EMT genes were analyzed using real time quantitative polymerase chain reaction (RT-qPCR, western blot and immunostaining in untreated and RhoGDI2 knock-down or overexpressing A549 cells in both in vivo and in vitro experimental settings. Results: Our study showed that the activity of Rac1, a key gene that is crucial for the initiation and metastasis of human lung adenocarcinoma, causing the redistribution of F-actin with partial loss of cell-cell adhesions and stress fibers, was significantly suppressed by RhoGDI2. RhoGDI2 promoted the expression of EMT marker gene E-cadherin and repressed EMT promoting genes Slug, Snail, α-SMA in both A549 cells and lung and liver organs derived from the mouse models. Knocking-down RhoGDI2 induced abnormal morphology for lung organs. Conclusion: These findings indicate that RhoGDI2 repressed the activity of Rac1 and may be involved in the rearrangement of cytoskeleton in lung cancer cells. RhoGDI2 suppresses the metastasis of lung cancer mediated through EMT by regulating the expression of key genes such as E-cadherin, Slug, Snail and α-SMA in both in vivo and in vitro models.

Measurement of Branching Fractions and CP-violating Charge Asymmetries in B sup + -> rho sup +pi sup 0 and B sup + -> rho sup 0 pi sup + decays, and search for B sup 0 -> rho sup 0 pi sup 0

CERN Document Server

Yu, Z

2003-01-01

The present preliminary measurements of branching fractions and CP-violating charge asymmetries in B-meson decays to rho pi. The data sample comprises 89 million UPSILON(4S) -> B(bar B) decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factor at SLAC. They find the charge-averaged branching fractions BETA(B sup + -> rho sup +pi sup 0) = (11.0 +- 1.9(stat.) +- 1.9(syst.)) x 10 sup - sup 6 and BETA(B sup + -> rho sup 0 pi sup +) = (9.3 +- 1.0(stat.) +- 0.8(syst.)) x 10 sup - sup 6; they set a 90% confidence-level upper limit of BETA(B sup 0 -> rho sup 0 pi sup 0) < 2.5 x 10 sup - sup 6. They measure the CP-violating charge asymmetries A sub C sub P suprho sup + suppi sup 0 = 0.23 +- 0.16(stat.) +- 0.06(syst.) and A sub C sub P suprho sup 0 suppi sup + = -0.17 +- 0.11(stat.) +- 0.02(syst.).

A tortoise-infecting picornavirus expands the host range of the family Picornaviridae.

Science.gov (United States)

Ng, Terry Fei Fan; Wellehan, James F X; Coleman, James K; Kondov, Nikola O; Deng, Xutao; Waltzek, Thomas B; Reuter, Gábor; Knowles, Nick J; Delwart, Eric

2015-05-01

While picornaviruses can cause diseases in many mammals, little is known of their host range for replication in non-mammalian vertebrates. Here, a picornavirus in liver and kidney tissues from diseased Sulawesi tortoises (Indotestudo forsteni) was genetically characterized. Tortoise rafivirus A (ToRaV-A, KJ415177) represents a potential new genus in the family Picornaviridae, for which we propose the name "Rafivirus". Our finding confirms the susceptibility of reptiles to picornaviruses.

Impact of liver fibrosis and fatty liver on T1rho measurements: A prospective study

International Nuclear Information System (INIS)

Xie, Shuang Shuang; Li, Qing; Cheng, Yue; Shen, Wen; Zhang, Yu; Zhuo, Zhi Zheng; Zhao, Guiming

2017-01-01

To investigate the liver T1rho values for detecting fibrosis, and the potential impact of fatty liver on T1rho measurements. This study included 18 healthy subjects, 18 patients with fatty liver, and 18 patients with liver fibrosis, who underwent T1rho MRI and mDIXON collections. Liver T1rho, proton density fat fraction (PDFF) and T2* values were measured and compared among the three groups. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the T1rho values for detecting liver fibrosis. Liver T1rho values were correlated with PDFF, T2* values and clinical data. Liver T1rho and PDFF values were significantly different (p 0.05). T1rho MRI is useful for noninvasive detection of liver fibrosis, and may not be affected with the presence of fatty liver

Accurate and reproducible measurements of RhoA activation in small samples of primary cells.

Science.gov (United States)

Nini, Lylia; Dagnino, Lina

2010-03-01

Rho GTPase activation is essential in a wide variety of cellular processes. Measurement of Rho GTPase activation is difficult with limited material, such as tissues or primary cells that exhibit stringent culture requirements for growth and survival. We defined parameters to accurately and reproducibly measure RhoA activation (i.e., RhoA-GTP) in cultured primary keratinocytes in response to serum and growth factor stimulation using enzyme-linked immunosorbent assay (ELISA)-based G-LISA assays. We also established conditions that minimize RhoA-GTP in unstimulated cells without affecting viability, allowing accurate measurements of RhoA activation on stimulation or induction of exogenous GTPase expression. Copyright 2009 Elsevier Inc. All rights reserved.

A solution to the rho-π puzzle: Spontaneously broken symmetries of the quark model

International Nuclear Information System (INIS)

Caldi, D.G.; Pagels, H.

1976-01-01

This article proposes a solution to the long-standing rho-π puzzle: How can the rho and π be members of a quark model U(6) 36 and the π be a Nambu-Goldstone boson satisfying partial conservation of the axial-vector current (PCAC) Our solution to the puzzle requires a revision of conventional concepts regarding the vector mesons rho, ω, K*, and phi. Just as the π is a Goldstone state, a collective excitation of the Nambu--Jona-Lasinio type, transforming as a member of the (3, 3) + (3, 3) representation of the chiral SU(3) x SU(3) group, so also the rho transforms like (3, 3) + (3, 3) and is also a collective state, a ''dormant'' Goldstone boson that is a true Goldstone boson in the static chiral U(6) x U(6) limit. The static chiral U(6) x U(6) is to be spontaneously broken to static U(6) in the vacuum. Relativisitc effects provide for U(6) breaking and a massive rho. This viewpoint has many consequences. Vector-meson dominance is a consequence of spontaneously broken chiral symmetry: the mechanism that couples the axial-vector current to the π couples the vector current to the rho. The transition rate is calculated as γ/sub rho/ -1 = f/sub pi//m/sub rho/ in rough agreement with experiment. This picture requires soft rho's to decouple. The chiral partner of the rho is not the A 1 but the B (1235). The experimental absence of the A 1 is no longer a theoretical embarrassment in this scheme. As the analog of PCAC for the pion we establish a tensor-field identity for the rho meson in which the rho is interpreted as a dormant Goldstone state. The decays delta → eta + π, B → ω + π, epsilon → 2π are estimated and are found to be in agreement with the observed rates. A static U(6) x U(6) generalization of the Σ model is presented with the π, rho, sigma, B in the (6, 6) + (6, 6) representation. The rho emerges as a dormant Goldstone boson in this model

Extremely low frequency electromagnetic fields promote mesenchymal stem cell migration by increasing intracellular Ca2+ and activating the FAK/Rho GTPases signaling pathways in vitro.

Science.gov (United States)

Zhang, Yingchi; Yan, Jiyuan; Xu, Haoran; Yang, Yong; Li, Wenkai; Wu, Hua; Liu, Chaoxu

2018-05-21

The ability of mesenchymal stem cells (MSCs) to migrate to the desired tissues or lesions is crucial for stem cell-based regenerative medicine and tissue engineering. Optimal therapeutics for promoting MSC migration are expected to become an effective means for tissue regeneration. Electromagnetic fields (EMF), as a noninvasive therapy, can cause a lot of biological changes in MSCs. However, whether EMF can promote MSC migration has not yet been reported. We evaluated the effects of EMF on cell migration in human bone marrow-derived MSCs. With the use of Helmholtz coils and an EMF stimulator, 7.5, 15, 30, 50, and 70 Hz/1 mT EMF was generated. Additionally, we employed the L-type calcium channel blocker verapamil and the focal adhesion kinase (FAK) inhibitor PF-573228 to investigate the role of intracellular calcium content, cell adhesion proteins, and the Rho GTPase protein family (RhoA, Rac1, and Cdc42) in EMF-mediated MSC migration. Cell adhesion proteins (FAK, talin, and vinculin) were detected by Western blot analysis. The Rho GTPase protein family activities were assessed by G-LISA, and F-actin levels, which reflect actin cytoskeletal organization, were detected using immunofluorescence. All the 7.5, 15, 30, 50, and 70 Hz/1 mT EMF promoted MSC migration. EMF increased MSC migration in an intracellular calcium-dependent manner. Notably, EMF-enhanced migration was mediated by FAK activation, which was critical for the formation of focal contacts, as evidenced by increased talin and vinculin expression. Moreover, RhoA, Rac1, and Cdc42 were activated by FAK to increase cytoskeletal organization, thus promoting cell contraction. EMF promoted MSC migration by increasing intracellular calcium and activating the FAK/Rho GTPase signaling pathways. This study provides insights into the mechanisms of MSC migration and will enable the rational design of targeted therapies to improve MSC engraftment.

Activation of rho is involved in the mechanism of hydrogen-peroxide-induced lung edema in isolated perfused rabbit lung.

Science.gov (United States)

Chiba, Y; Ishii, Y; Kitamura, S; Sugiyama, Y

2001-09-01

Acute lung injury is attributed primarily to increased vascular permeability caused by reactive oxygen species derived from neutrophils, such as hydrogen peroxide (H2O2). Increased permeability is accompanied by the contraction and cytoskeleton reorganization of endothelial cells, resulting in intercellular gap formation. The Rho family of Ras-like GTPases is implicated in the regulation of the cytoskeleton and cell contraction. We examined the role of Rho in H2O2-induced pulmonary edema with the use of isolated perfused rabbit lungs. To our knowledge, this is the first study to examine the role of Rho in increased vascular permeability induced by H2O2 in perfused lungs. Vascular permeability was evaluated on the basis of the capillary filtration coefficient (Kfc, ml/min/cm H2O/100 g). We found that H2O2 (300 microM) increased lung weight, Kfc, and pulmonary capillary pressure. These effects of H2O2 were abolished by treatment with Y-27632 (50 microM), an inhibitor of the Rho effector p160 ROCK. In contrast, the muscular relaxant papaverine inhibited the H2O2-induced rise in pulmonary capillary pressure, but did not suppress the increases in lung weight and Kfc. These findings indicate that H2O2 causes pulmonary edema by elevating hydrostatic pressure and increasing vascular permeability. Y-27632 inhibited the formation of pulmonary edema by blocking both of these H2O2-induced effects. Our results suggest that Rho-related pathways have a part in the mechanism of H2O2-induced pulmonary edema. Copyright 2001 Academic Press.

Tye7 regulates yeast Ty1 retrotransposon sense and antisense transcription in response to adenylic nucleotides stress.

Science.gov (United States)

Servant, Géraldine; Pinson, Benoit; Tchalikian-Cosson, Aurélie; Coulpier, Fanny; Lemoine, Sophie; Pennetier, Carole; Bridier-Nahmias, Antoine; Todeschini, Anne Laure; Fayol, Hélène; Daignan-Fornier, Bertrand; Lesage, Pascale

2012-07-01

Transposable elements play a fundamental role in genome evolution. It is proposed that their mobility, activated under stress, induces mutations that could confer advantages to the host organism. Transcription of the Ty1 LTR-retrotransposon of Saccharomyces cerevisiae is activated in response to a severe deficiency in adenylic nucleotides. Here, we show that Ty2 and Ty3 are also stimulated under these stress conditions, revealing the simultaneous activation of three active Ty retrotransposon families. We demonstrate that Ty1 activation in response to adenylic nucleotide depletion requires the DNA-binding transcription factor Tye7. Ty1 is transcribed in both sense and antisense directions. We identify three Tye7 potential binding sites in the region of Ty1 DNA sequence where antisense transcription starts. We show that Tye7 binds to Ty1 DNA and regulates Ty1 antisense transcription. Altogether, our data suggest that, in response to adenylic nucleotide reduction, TYE7 is induced and activates Ty1 mRNA transcription, possibly by controlling Ty1 antisense transcription. We also provide the first evidence that Ty1 antisense transcription can be regulated by environmental stress conditions, pointing to a new level of control of Ty1 activity by stress, as Ty1 antisense RNAs play an important role in regulating Ty1 mobility at both the transcriptional and post-transcriptional stages.

Peptide substrates for Rho-associated kinase 2 (Rho-kinase 2/ROCK2.

Directory of Open Access Journals (Sweden)

Jeong-Hun Kang

Full Text Available Peptide substrates sensitive for a certain protein kinase could be important for new-drug development and to understand the mechanism of diseases. Rho-associated kinase (Rho-kinase/ROCK is a serine/threonine kinase, and plays an important part in cardiovascular disease, migration and invasion of tumor cells, and in neurological disorders. The purpose of this study was to find substrates with high affinity and sensitivity for ROCK2. We synthesized 136 peptide substrates from protein substrates for ROCK2 with different lengths and charged peptides. Incorporation of (32P [counts per minute (CPM] for each peptide substrate was determined by the radiolabel assay using [γ-(32P]ATP. When the top five peptide substrates showing high CPMs (R4, R22, R133, R134, and R135 were phosphorylated by other enzymes (PKA, PKCα, and ERK1, R22, R133, and R135 displayed the highest CPM level for ROCK2 compared with other enzymes, whereas R4 and R134 showed similar CPM levels for ROCK2 and PKCα. We hypothesize that R22, R133, and R135 can be useful peptide substrates for ROCK2.

ER stress in retinal degeneration in S334ter Rho rats.

Directory of Open Access Journals (Sweden)

Vishal M Shinde

Full Text Available The S334ter rhodopsin (Rho rat (line 4 bears the rhodopsin gene with an early termination codon at residue 334 that is a model for several such mutations found in human patients with autosomal dominant retinitis pigmentosa (ADRP. The Unfolded Protein Response (UPR is implicated in the pathophysiology of several retinal disorders including ADRP in P23H Rho rats. The aim of this study was to examine the onset of UPR gene expression in S334ter Rho retinas to determine if UPR is activated in ADRP animal models and to investigate how the activation of UPR molecules leads to the final demise of S334ter Rho photoreceptors. RT-PCR was performed to evaluate the gene expression profiles for the P10, P12, P15, and P21 stages of the development and progression of ADRP in S334ter Rho photoreceptors. We determined that during the P12-P15 period, ER stress-related genes are strongly upregulated in transgenic retinas, resulting in the activation of the UPR that was confirmed using western blot analysis and RT-PCR. The activation of UPR was associated with the increased expression of JNK, Bik, Bim, Bid, Noxa, and Puma genes and cleavage of caspase-12 that together with activated calpains presumably compromise the integrity of the mitochondrial MPTP, leading to the release of pro-apoptotic AIF1 into the cytosol of S334ter Rho photoreceptor cells. Therefore, two major cross-talking pathways, the UPR and mitochondrial MPTP occur in S334ter-4 Rho retina concomitantly and eventually promote the death of the photoreceptor cells.

Coevolution of a Persistent Plant Virus and Its Pepper Hosts.

Science.gov (United States)

Safari, Maliheh; Roossinck, Marilyn J

2018-05-30

There are many nonpathogenic viruses that are maintained in a persistent lifestyle in plants. Plant persistent viruses are widespread, replicating in their hosts for many generations. So far, Endornaviridae is the only family of plant persistent viruses with a single-stranded RNA genome, containing one large open reading frame. Bell pepper endornavirus (BPEV), Hot pepper endornavirus, Capsicum frutescens endornavirus 1 (CFEV 1) have been identified from peppers. Peppers are native to Central and South America and, as domesticated plants, human selection accelerated their evolution. We investigated the evolution of these endornaviruses in different peppers including Capsicum annuum, C. chacoense, C.chinense, C. frutescens, C.bacccutum, and C. pubescens using two fragments from the viral helicase (Hel) and RNA dependent RNA polymerase (RdRp) domains. In addition, using single nucleotide polymorphisms, we analyzed the pepper host populations and phylogenies. The endornaviruses phylogeny was correlated with its Capsicum species host. In this study, BPEV was limited to C. annuum species, and the RdRp and Hel phylogenies identified two clades that correlated with the host pungency. No C. annuum infected with CFEV 1 was found in this study, but the CFEV 1 RdRp fragment was recovered from C. chinense, C. frutescens, C. bacccutum, and C. pubescens. Hence, during pepper speciation, the ancestor of CFEV 1 may have evolved as a new endornavirus, BPEV, in C. annuum peppers.

Table of charged particle energies versus magnetic field strength x orbit radius (B{rho}) for A = 1 to 7 (100< (B{rho}) < 1200 kG.cm); Table des energies des particules chargees en fonction de la rigidite magnetique (B{rho}) pour A = 1 a 7 (100< (B{rho}) < 1200 kG.cm)

Energy Technology Data Exchange (ETDEWEB)

Bianchi, L. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-07-01

A table of charged particle energies versus magnetic field strength x orbit radius (B{sub {rho}}) is presented. Particles p, d, t, {sup 3}He{sup ++}, {sup 4}He{sup +}, {sup 4}He{sup ++}, {sup 6}Li{sup +}, {sup 6}Li{sup ++}, {sup 6}Li{sup +++}, {sup 7}Li{sup +}, {sup 7}Li{sup ++}, {sup 7}Li{sup +++}. Values of B{sub {rho}}: 100 to 1200 kG.cm by steps of 0.5 kG.cm. Values of energies are given in keV. (author) [French] Nous presentons une table des energies de protons, deutons, tritons, {sup 3}He{sup ++}, {sup 4}He{sup +}, {sup 4}He{sup ++}, {sup 6}Li{sup +}, {sup 6}Li{sup ++}, {sup 6}Li{sup +++}, {sup 7}Li{sup +}, {sup 7}Li{sup ++}, {sup 7}Li{sup +++} en fonction de leur rigidite magnetique (B{sub {rho}}). Les valeurs de B{sub {rho}} sont comprises entre 100 et 1200 kG.cm par pas de 0.5 kG.cm. Les valeurs des energies sont donnees en keV. (auteur)

Study of the decay B0(barB0) --> rho+rho-, and constraints on the CKM angle α

International Nuclear Information System (INIS)

Aubert, B.; Babar Collaboration

2004-01-01

Using a data sample of 89 million Υ(4S)-->BBbar decays collected with the BaBar detector at the PEP-II asymmetric B Factory at SLAC, we measure the B 0 (barB 0 )-->rho + rho - branching fraction as (30+-4 (stat)+-5(syst)) x 10 -6 and a longitudinal polarization fraction of f L 0.99+-0.03(stat) +0.04 ) -0.03 (syst). We measure the time-dependent-asymmetry parameters of the longitudinally polarized component of this decay as C L = -0.17+-0.27(stat)+-0.14 (syst) and S L -0.42+-0.42(stat)+-0.14(syst). We present constraints on the CKM angle α

Differential evolution of members of the rhomboid gene family with conservative and divergent patterns.

Science.gov (United States)

Li, Qi; Zhang, Ning; Zhang, Liangsheng; Ma, Hong

2015-04-01

Rhomboid proteins are intramembrane serine proteases that are involved in a plethora of biological functions, but the evolutionary history of the rhomboid gene family is not clear. We performed a comprehensive molecular evolutionary analysis of the rhomboid gene family and also investigated the organization and sequence features of plant rhomboids in different subfamilies. Our results showed that eukaryotic rhomboids could be divided into five subfamilies (RhoA-RhoD and PARL). Most orthology groups appeared to be conserved only as single or low-copy genes in all lineages in RhoB-RhoD and PARL, whereas RhoA genes underwent several duplication events, resulting in multiple gene copies. These duplication events were due to whole genome duplications in plants and animals and the duplicates might have experienced functional divergence. We also identified a novel group of plant rhomboid (RhoB1) that might have lost their enzymatic activity; their existence suggests that they might have evolved new mechanisms. Plant and animal rhomboids have similar evolutionary patterns. In addition, there are mutations affecting key active sites in RBL8, RBL9 and one of the Brassicaceae PARL duplicates. This study delineates a possible evolutionary scheme for intramembrane proteins and illustrates distinct fates and a mechanism of evolution of gene duplicates. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

Codivergence of mycoviruses with their hosts.

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Markus Göker

Full Text Available BACKGROUND: The associations between pathogens and their hosts are complex and can result from any combination of evolutionary events such as codivergence, switching, and duplication of the pathogen. Mycoviruses are RNA viruses which infect fungi and for which natural vectors are so far unknown. Thus, lateral transfer might be improbable and codivergence their dominant mode of evolution. Accordingly, mycoviruses are a suitable target for statistical tests of virus-host codivergence, but inference of mycovirus phylogenies might be difficult because of low sequence similarity even within families. METHODOLOGY: We analyzed here the evolutionary dynamics of all mycovirus families by comparing virus and host phylogenies. Additionally, we assessed the sensitivity of the co-phylogenetic tests to the settings for inferring virus trees from their genome sequences and approximate, taxonomy-based host trees. CONCLUSIONS: While sequence alignment filtering modes affected branch support, the overall results of the co-phylogenetic tests were significantly influenced only by the number of viruses sampled per family. The trees of the two largest families, Partitiviridae and Totiviridae, were significantly more similar to those of their hosts than expected by chance, and most individual host-virus links had a significant positive impact on the global fit, indicating that codivergence is the dominant mode of virus diversification. However, in this regard mycoviruses did not differ from closely related viruses sampled from non-fungus hosts. The remaining virus families were either dominated by other evolutionary modes or lacked an apparent overall pattern. As this negative result might be caused by insufficient taxon sampling, the most parsimonious hypothesis still is that host-parasite evolution is basically the same in all mycovirus families. This is the first study of mycovirus-host codivergence, and the results shed light not only on how mycovirus biology

Rational Design of Rho Protein Inhibitors

National Research Council Canada - National Science Library

Rojas, Rafael J

2006-01-01

Rho GTPases are molecular switches that fluctuate between on and off states. When active, these proteins function to remodel the actin cytoskeleton by interacting with a number of downstream effector molecules...

Rational Design of Rho Protein Inhibitors

National Research Council Canada - National Science Library

Rojas, Rafael J

2005-01-01

Rho GTPases are molecular switches that fluctuate between on and off states. When active, these proteins function to remodel the actin cytoskeleton by interacting with a number of downstream effector molecules...

Critique of Dilley's N/D generation of the rho resonance

International Nuclear Information System (INIS)

Tryon, E.P.

1977-01-01

Rigorous sum rules for negative moments of the discontinuity across the left-hand cut of the ππ P wave are derived and analyzed. A model by Dilley wherein the rho resonance emerges from elastic N/D equations is shown to be severely inconsistent with these sum rules. Dilley's method for selecting the input left cut is analyzed and shown to be strongly biased in favor of generating a rho. Because of this bias, together with the aforementioned violation of sum rules, Dilley's model does not comprise evidence that the rho is generated by forces in the ππ channel. Numerous successes of the quark model suggest otherwise

Everyday Experiences of 18- to 36-Month-Old Children from Migrant Families: The Influence of Host Culture and Migration Experience

Science.gov (United States)

Driessen, Ricarda; Leyendecker, Birgit; Scholmerich, Axel; Harwood, Robin

2010-01-01

We explored the everyday experiences of 18- to 36-month-old toddlers at two study sites and the influence of adaptation to the host culture on the everyday experiences of children from migrant families. First- and second-generation Puerto Rican families in Connecticut, USA, first- and second-generation Turkish families in Bochum, Germany, as well…

Rotation in USco and rho Oph with K2

Science.gov (United States)

Rebull, Luisa; Stauffer, John; K2 Clusters Team

2018-01-01

K2 observed Upper Scorpius and rho Oph as part of their Campaign 2 in 2014. At ~8 and ~1 Myr respectively, the stars in Upper Sco and rho Oph exhibit greater diversity of light curve shapes than are found in older clusters observed with K2 such as Pleiades or Praesepe. Nonetheless, we are able to derive rotation periods for 85% (971/1136) of the USco members and 80% (71/88) of the rho Oph members. About 25% of the periodic stars have evidence for multiple periods. These light curves sample smaller amplitudes to lower masses and with a far better cadence, than has even been probed before. We can compare USco with similar stars in Praesepe (~700 Myr) and the Pleiades (~125 Myr), all with K2 light curves.

RhoA/ROCK downregulates FPR2-mediated NADPH oxidase activation in mouse bone marrow granulocytes.

Science.gov (United States)

Filina, Julia V; Gabdoulkhakova, Aida G; Safronova, Valentina G

2014-10-01

Polymorphonuclear neutrophils (PMNs) express the high and low affinity receptors to formylated peptides (mFPR1 and mFPR2 in mice, accordingly). RhoA/ROCK (Rho activated kinase) pathway is crucial for cell motility and oxidase activity regulated via FPRs. There are contradictory data on RhoA-mediated regulation of NADPH oxidase activity in phagocytes. We have shown divergent Rho GTPases signaling via mFPR1 and mFPR2 to NADPH oxidase in PMNs from inflammatory site. The present study was aimed to find out the role of RhoA/ROCK in the respiratory burst activated via mFPR1 and mFPR2 in the bone marrow PMNs. Different kinetics of RhoA activation were detected with 0.1μM fMLF and 1μM WKYMVM operating via mFPR1 and mFPR2, accordingly. RhoA was translocated in fMLF-activated cells towards the cell center and juxtamembrane space versus uniform allocation in the resting cells. Specific inhibition of RhoA by CT04, Rho inhibitor I, weakly depressed the respiratory burst induced via mFPR1, but significantly increased the one induced via mFPR2. Inhibition of ROCK, the main effector of RhoA, by Y27632 led to the same effect on the respiratory burst. Regulation of mFPR2-induced respiratory response by ROCK was impossible under the cytoskeleton disruption by cytochalasin D, whereas it persisted in the case of mFPR1 activation. Thus we suggest RhoA to be one of the regulatory and signal transduction components in the respiratory burst through FPRs in the mouse bone marrow PMNs. Both mFPR1 and mFPR2 binding with a ligand trigger the activation of RhoA. FPR1 signaling through RhoA/ROCK increases NADPH-oxidase activity. But in FPR2 action RhoA/ROCK together with cytoskeleton-linked systems down-regulates NADPH-oxidase. This mechanism could restrain the reactive oxygen species dependent damage of own tissues during the chemotaxis of PMNs and in the resting cells. Copyright © 2014 Elsevier Inc. All rights reserved.

Corrections to the rho-parameter due to a heavy Higgs particle

International Nuclear Information System (INIS)

Bij, J.J. van der.

1983-01-01

The main part of this thesis is concerned with the calculation of the two-loop contribution to the rho-parameter, i.e. the ratio of charged and neutral vector boson masses, due to a heavy Higgs particle. It involves the calculation of a large number of Feynman diagrams. The result is that a contribution growing like m 2 exists (m = Higgs mass), but it does not correspond to the poles at n=3 in the non-linear model. First the model is introduced, the precise definition of rho is given and the formal connection with the non-linear model is derived. Then the one-loop infinities are calculated. It is shown that no m 2 corrections are observable in one loop and the log m 2 correction to rho is calculated. Finally the two-loop correction to rho is calculated. (Auth.)

Repeat-associated plasticity in the Helicobacter pylori RD gene family.

Science.gov (United States)

Shak, Joshua R; Dick, Jonathan J; Meinersmann, Richard J; Perez-Perez, Guillermo I; Blaser, Martin J

2009-11-01

The bacterium Helicobacter pylori is remarkable for its ability to persist in the human stomach for decades without provoking sterilizing immunity. Since repetitive DNA can facilitate adaptive genomic flexibility via increased recombination, insertion, and deletion, we searched the genomes of two H. pylori strains for nucleotide repeats. We discovered a family of genes with extensive repetitive DNA that we have termed the H. pylori RD gene family. Each gene of this family is composed of a conserved 3' region, a variable mid-region encoding 7 and 11 amino acid repeats, and a 5' region containing one of two possible alleles. Analysis of five complete genome sequences and PCR genotyping of 42 H. pylori strains revealed extensive variation between strains in the number, location, and arrangement of RD genes. Furthermore, examination of multiple strains isolated from a single subject's stomach revealed intrahost variation in repeat number and composition. Despite prior evidence that the protein products of this gene family are expressed at the bacterial cell surface, enzyme-linked immunosorbent assay and immunoblot studies revealed no consistent seroreactivity to a recombinant RD protein by H. pylori-positive hosts. The pattern of repeats uncovered in the RD gene family appears to reflect slipped-strand mispairing or domain duplication, allowing for redundancy and subsequent diversity in genotype and phenotype. This novel family of hypervariable genes with conserved, repetitive, and allelic domains may represent an important locus for understanding H. pylori persistence in its natural host.

RhoC is essential for TGF-β1-induced invasive capacity of rat ascites hepatoma cells

International Nuclear Information System (INIS)

Mukai, M.; Endo, H.; Iwasaki, T.; Tatsuta, M.; Togawa, A.; Nakamura, H.; Inoue, M.

2006-01-01

Transforming growth factor-β1 (TGF-β1) is a multifunctional growth factor that plays a role in cell proliferation, differentiation, extracellular matrix production, apoptosis, and cell motility. We show here that TGF-β1 increased the invasiveness of MM1 cells, which are a highly invasive clone of rat ascites hepatoma cells. Both mRNA and protein levels of RhoC but not RhoA in TGF-β1-treated MM1 cells increased. In parallel with this increase in expression, RhoC activity was induced by TGF-β1 treatment. When RhoC was overexpressed in MM1 cells, the invasive capacity increased. The RhoC-overexpressing cells formed more nodules than did mock cells when injected into rat peritoneum. Furthermore, when RhoC expression was reduced by transfection with shRNA/RhoC, the invasiveness of MM1 cells decreased with concomitant suppression of RhoC expression. Thus, the induced expression of RhoC by TGF-β1 in MM1 cells plays a critical role in TGF-β1-induced cell migration

DNA topoisomerase IIβ stimulates neurite outgrowth in neural differentiated human mesenchymal stem cells through regulation of Rho-GTPases (RhoA/Rock2 pathway) and Nurr1 expression.

Science.gov (United States)

Zaim, Merve; Isik, Sevim

2018-04-25

DNA topoisomerase IIβ (topo IIβ) is known to regulate neural differentiation by inducing the neuronal genes responsible for critical neural differentiation events such as neurite outgrowth and axon guidance. However, the pathways of axon growth controlled by topo IIβ have not been clarified yet. Microarray results of our previous study have shown that topo IIβ silencing in neural differentiated primary human mesenchymal stem cells (hMSCs) significantly alters the expression pattern of genes involved in neural polarity, axonal growth, and guidance, including Rho-GTPases. This study aims to further analyze the regulatory role of topo IIβ on the process of axon growth via regulation of Rho-GTPases. For this purpose, topo IIβ was silenced in neurally differentiated hMSCs. Cells lost their morphology because of topo IIβ deficiency, becoming enlarged and flattened. Additionally, a reduction in both neural differentiation efficiency and neurite length, upregulation in RhoA and Rock2, downregulation in Cdc42 gene expression were detected. On the other hand, cells were transfected with topo IIβ gene to elucidate the possible neuroprotective effect of topo IIβ overexpression on neural-induced hMSCs. Topo IIβ overexpression prompted all the cells to exhibit neural cell morphology as characterized by longer neurites. RhoA and Rock2 expressions were downregulated, whereas Cdc42 expression was upregulated. Nurr1 expression level correlated with topo IIβ in both topo IIβ-overexpressed and -silenced cells. Furthermore, differential translocation of Rho-GTPases was detected by immunostaining in response to topo IIβ. Our results suggest that topo IIβ deficiency could give rise to neurodegeneration through dysregulation of Rho-GTPases. However, further in-vivo research is needed to demonstrate if re-regulation of Rho GTPases by topo IIβ overexpression could be a neuroprotective treatment in the case of neurodegenerative diseases.

Diffractive {rho} production with an AdS/QCD holographic wavefunction for the {rho} meson

Energy Technology Data Exchange (ETDEWEB)

Forshaw, Jeff [University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Sandapen, Ruben [Universite de Moncton, Moncton, N-B, E1A 3E9 (Canada) and Mount Allison University, Sackville, N-B, E46 1E6 (Canada)

2013-04-15

We report on the results of our recent research published in [1] that shows that AdS/QCD generates predictions for the rate of diffractive {rho}-meson electroproduction that are in agreement with data collected at the HERA electron-proton collider [2, 3]. Preliminary results of this research were presented in [4].

A RhoA-FRET Biosensor Mouse for Intravital Imaging in Normal Tissue Homeostasis and Disease Contexts

Directory of Open Access Journals (Sweden)

Max Nobis

2017-10-01

Full Text Available The small GTPase RhoA is involved in a variety of fundamental processes in normal tissue. Spatiotemporal control of RhoA is thought to govern mechanosensing, growth, and motility of cells, while its deregulation is associated with disease development. Here, we describe the generation of a RhoA-fluorescence resonance energy transfer (FRET biosensor mouse and its utility for monitoring real-time activity of RhoA in a variety of native tissues in vivo. We assess changes in RhoA activity during mechanosensing of osteocytes within the bone and during neutrophil migration. We also demonstrate spatiotemporal order of RhoA activity within crypt cells of the small intestine and during different stages of mammary gestation. Subsequently, we reveal co-option of RhoA activity in both invasive breast and pancreatic cancers, and we assess drug targeting in these disease settings, illustrating the potential for utilizing this mouse to study RhoA activity in vivo in real time.

Shifts in diversification rates and host jump frequencies shaped the diversity of host range among Sclerotiniaceae fungal plant pathogens

OpenAIRE

Taylor, Andrew; Clarkson, John; Raffaele, Sylvain; Navaud, Olivier; Barbacci, Adelin

2017-01-01

The range of hosts that a parasite can infect in nature is a trait determined by its own evolutionary history and that of its potential hosts. However, knowledge on host range diversity and evolution at the family level is often lacking. Here, we investigate host range variation and diversification trends within the Sclerotiniaceae , a family of Ascomycete fungi. Using a phylogenetic framework, we associate diversification rates, the frequency of host jump events, and host range variation dur...

Ang II-AT2R increases mesenchymal stem cell migration by signaling through the FAK and RhoA/Cdc42 pathways in vitro.

Science.gov (United States)

Xu, Xiu-Ping; He, Hong-Li; Hu, Shu-Ling; Han, Ji-Bin; Huang, Li-Li; Xu, Jing-Yuan; Xie, Jian-Feng; Liu, Ai-Ran; Yang, Yi; Qiu, Hai-Bo

2017-07-12

Mesenchymal stem cells (MSCs) migrate via the bloodstream to sites of injury and are possibly attracted by inflammatory factors. As a proinflammatory mediator, angiotensin II (Ang II) reportedly enhances the migration of various cell types by signaling via the Ang II receptor in vitro. However, few studies have focused on the effects of Ang II on MSC migration and the underlying mechanisms. Human bone marrow MSCs migration was measured using wound healing and Boyden chamber migration assays after treatments with different concentrations of Ang II, an AT1R antagonist (Losartan), and/or an AT2R antagonist (PD-123319). To exclude the effect of proliferation on MSC migration, we measured MSC proliferation after stimulation with the same concentration of Ang II. Additionally, we employed the focal adhesion kinase (FAK) inhibitor PF-573228, RhoA inhibitor C3 transferase, Rac1 inhibitor NSC23766, or Cdc42 inhibitor ML141 to investigate the role of cell adhesion proteins and the Rho-GTPase protein family (RhoA, Rac1, and Cdc42) in Ang II-mediated MSC migration. Cell adhesion proteins (FAK, Talin, and Vinculin) were detected by western blot analysis. The Rho-GTPase family protein activities were assessed by G-LISA and F-actin levels, which reflect actin cytoskeletal organization, were detected by using immunofluorescence. Human bone marrow MSCs constitutively expressed AT1R and AT2R. Additionally, Ang II increased MSC migration in an AT2R-dependent manner. Notably, Ang II-enhanced migration was not mediated by Ang II-mediated cell proliferation. Interestingly, Ang II-enhanced migration was mediated by FAK activation, which was critical for the formation of focal contacts, as evidenced by increased Talin and Vinculin expression. Moreover, RhoA and Cdc42 were activated by FAK to increase cytoskeletal organization, thus promoting cell contraction. Furthermore, FAK, Talin, and Vinculin activation and F-actin reorganization in response to Ang II were prevented by PD-123319 but

The host plant metabolite glucose is the precursor of diffusible signal factor (DSF) family signals in Xanthomonas campestris.

Science.gov (United States)

Deng, Yinyue; Liu, Xiaoling; Wu, Ji'en; Lee, Jasmine; Chen, Shaohua; Cheng, Yingying; Zhang, Chunyan; Zhang, Lian-Hui

2015-04-01

Plant pathogen Xanthomonas campestris pv. campestris produces cis-11-methyl-2-dodecenoic acid (diffusible signal factor [DSF]) as a cell-cell communication signal to regulate biofilm dispersal and virulence factor production. Previous studies have demonstrated that DSF biosynthesis is dependent on the presence of RpfF, an enoyl-coenzyme A (CoA) hydratase, but the DSF synthetic mechanism and the influence of the host plant on DSF biosynthesis are still not clear. We show here that exogenous addition of host plant juice or ethanol extract to the growth medium of X. campestris pv. campestris could significantly boost DSF family signal production. It was subsequently revealed that X. campestris pv. campestris produces not only DSF but also BDSF (cis-2-dodecenoic acid) and another novel DSF family signal, which was designated DSF-II. BDSF was originally identified in Burkholderia cenocepacia to be involved in regulation of motility, biofilm formation, and virulence in B. cenocepacia. Functional analysis suggested that DSF-II plays a role equal to that of DSF in regulation of biofilm dispersion and virulence factor production in X. campestris pv. campestris. Furthermore, chromatographic separation led to identification of glucose as a specific molecule stimulating DSF family signal biosynthesis in X. campestris pv. campestris. (13)C-labeling experiments demonstrated that glucose acts as a substrate to provide a carbon element for DSF biosynthesis. The results of this study indicate that X. campestris pv. campestris could utilize a common metabolite of the host plant to enhance DSF family signal synthesis and therefore promote virulence. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Photoproduction of $\\rho^0$ in ultra--peripheral nuclear collisions at ALICE

CERN Document Server

Skjerdal, Kyrre

2013-01-01

Photoproduction of $\\rho^0$ mesons in ultra-peripheral Pb+Pb collisions has been studied by the ALICE Collaboration at the CERN LHC. The strong photon flux associated with relativistic charged nuclei leads to a very large cross section for exclusive photoproduction of $\\rho^0$ meson in interactions of the type $Pb + Pb \\rightarrow Pb + Pb + \\rho^0$. For a $\\rho^0$ produced at mid-rapidity at the LHC, the photon-nucleus center of mass energy is higher than in any previous experiment. The ALICE detector is a general purpose detector dedicated to study heavy--ion collisions. ALICE has excellent performance in the low $p_T$ region, and can reconstruct charged particle tracks with 0.1 GeV/c $\\leq p_T \\leq 100$ GeV/c. In this analysis all tracks were required to be within ALICE's central barrel. Analysis of data from the first heavy ion run at the LHC in 2010 will be discussed in this paper.

Between Three Worlds: Host, Homeland, and Global Media in the Lives of Russian Immigrant Families in Israel and Germany

Science.gov (United States)

Elias, Nelly; Lemish, Dafna

2011-01-01

This study investigated various roles played by host, homeland, and global media in the lives of immigrant families from the Commonwealth of Independent States (CIS, former USSR) to Israel and Germany, as well as the place of different media in family conflicts, consolidation, and parenting strategies. The study was based on focus group interviews…

RhoA: A therapeutic target for chronic myeloid leukemia

Directory of Open Access Journals (Sweden)

Molli Poonam R

2012-03-01

Full Text Available Abstract Background Chronic Myeloid Leukemia (CML is a malignant pluripotent stem cells disorder of myeloid cells. In CML patients, polymorphonuclear leukocytes (PMNL the terminally differentiated cells of myeloid series exhibit defects in several actin dependent functions such as adhesion, motility, chemotaxis, agglutination, phagocytosis and microbicidal activities. A definite and global abnormality was observed in stimulation of actin polymerization in CML PMNL. Signalling molecules ras and rhoGTPases regulate spatial and temporal polymerization of actin and thus, a broad range of physiological processes. Therefore, status of these GTPases as well as actin was studied in resting and fMLP stimulated normal and CML PMNL. Methods To study expression of GTPases and actin, Western blotting and flow cytometry analysis were done, while spatial expression and colocalization of these proteins were studied by using laser confocal microscopy. To study effect of inhibitors on cell proliferation CCK-8 assay was done. Significance of differences in expression of proteins within the samples and between normal and CML was tested by using Wilcoxon signed rank test and Mann-Whitney test, respectively. Bivariate and partial correlation analyses were done to study relationship between all the parameters. Results In CML PMNL, actin expression and its architecture were altered and stimulation of actin polymerization was absent. Differences were also observed in expression, organization or stimulation of all the three GTPases in normal and CML PMNL. In normal PMNL, ras was the critical GTPase regulating expression of rhoGTPases and actin and actin polymerization. But in CML PMNL, rhoA took a central place. In accordance with these, treatment with rho/ROCK pathway inhibitors resulted in specific growth inhibition of CML cell lines. Conclusions RhoA has emerged as the key molecule responsible for functional defects in CML PMNL and therefore can be used as a

The high genetic variation of viruses of the genus Nairovirus reflects the diversity of their predominant tick hosts

International Nuclear Information System (INIS)

Honig, Jessica E.; Osborne, Jane C.; Nichol, Stuart T.

2004-01-01

The genus Nairovirus (family Bunyaviridae) contains seven serogroups consisting of 34 predominantly tick-borne viruses, including several associated with severe human and livestock diseases [e.g., Crimean Congo hemorrhagic fever (CCHF) and Nairobi sheep disease (NSD), respectively]. Before this report, no comparative genetic studies or molecular detection assays had been developed for this virus genus. To characterize at least one representative from each of the seven serogroups, reverse transcriptase-polymerase chain reaction (RT-PCR) primers targeting the L polymerase-encoding region of the RNA genome of these viruses were successfully designed based on conserved amino acid motifs present in the predicted catalytic core region. Sequence analysis showed the nairoviruses to be a highly diverse group, exhibiting up to 39.4% and 46.0% nucleotide and amino acid identity differences, respectively. Virus genetic relationships correlated well with serologic groupings and with tick host associations. Hosts of these viruses include both the hard (family Ixodidae) and soft (family Argasidae) ticks. Virus phylogenetic analysis reveals two major monophyletic groups: hard tick and soft tick-vectored viruses. In addition, viruses vectored by Ornithodoros, Carios, and Argas genera ticks also form three separate monophyletic lineages. The striking similarities between tick and nairovirus phylogenies are consistent with possible coevolution of the viruses and their tick hosts. Fossil and phylogenetic data placing the hard tick-soft tick divergence between 120 and 92 million years ago suggest an ancient origin for viruses of the genus Nairovirus

Impact of liver fibrosis and fatty liver on T1rho measurements: A prospective study

Energy Technology Data Exchange (ETDEWEB)

Xie, Shuang Shuang; Li, Qing; Cheng, Yue; Shen, Wen [Dept. of Radiology, Tianjin First Center Hospital, Tianjin (China); Zhang, Yu; Zhuo, Zhi Zheng [Clinical Science, Philips Healthcare, Beijing (China); Zhao, Guiming [Dept. of Hepatology, Tianjin Second People' s Hospital, Tianjin (China)

2017-11-15

To investigate the liver T1rho values for detecting fibrosis, and the potential impact of fatty liver on T1rho measurements. This study included 18 healthy subjects, 18 patients with fatty liver, and 18 patients with liver fibrosis, who underwent T1rho MRI and mDIXON collections. Liver T1rho, proton density fat fraction (PDFF) and T2* values were measured and compared among the three groups. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the T1rho values for detecting liver fibrosis. Liver T1rho values were correlated with PDFF, T2* values and clinical data. Liver T1rho and PDFF values were significantly different (p < 0.001), whereas the T2* (p = 0.766) values were similar, among the three groups. Mean liver T1rho values in the fibrotic group (52.6 ± 6.8 ms) were significantly higher than those of healthy subjects (44.9 ± 2.8 ms, p < 0.001) and fatty liver group (45.0 ± 3.5 ms, p < 0.001). Mean liver T1rho values were similar between healthy subjects and fatty liver group (p = 0.999). PDFF values in the fatty liver group (16.07 ± 10.59%) were significantly higher than those of healthy subjects (1.43 ± 1.36%, p < 0.001) and fibrosis group (1.07 ± 1.06%, p < 0.001). PDFF values were similar in healthy subjects and fibrosis group (p = 0.984). Mean T1rho values performed well to detect fibrosis at a threshold of 49.5 ms (area under the ROC curve, 0.855), had a moderate correlation with liver stiffness (r = 0.671, p = 0.012), and no correlation with PDFF, T2* values, subject age, or body mass index (p > 0.05). T1rho MRI is useful for noninvasive detection of liver fibrosis, and may not be affected with the presence of fatty liver.

Genome-wide identification and tissue-specific expression analysis of nucleotide binding site-leucine rich repeat gene family in Cicer arietinum (kabuli chickpea).

Science.gov (United States)

Sharma, Ranu; Rawat, Vimal; Suresh, C G

2017-12-01

The nucleotide binding site-leucine rich repeat (NBS-LRR) proteins play an important role in the defense mechanisms against pathogens. Using bioinformatics approach, we identified and annotated 104 NBS-LRR genes in chickpea. Phylogenetic analysis points to their diversification into two families namely TIR-NBS-LRR and non-TIR-NBS-LRR. Gene architecture revealed intron gain/loss events in this resistance gene family during their independent evolution into two families. Comparative genomics analysis elucidated its evolutionary relationship with other fabaceae species. Around 50% NBS-LRRs reside in macro-syntenic blocks underlining positional conservation along with sequence conservation of NBS-LRR genes in chickpea. Transcriptome sequencing data provided evidence for their transcription and tissue-specific expression. Four cis -regulatory elements namely WBOX, DRE, CBF, and GCC boxes, that commonly occur in resistance genes, were present in the promoter regions of these genes. Further, the findings will provide a strong background to use candidate disease resistance NBS-encoding genes and identify their specific roles in chickpea.

Control of Homeostasis and Dendritic Cell Survival by the GTPase RhoA

DEFF Research Database (Denmark)

Li, Shuai; Dislich, Bastian; Brakebusch, Cord H

2015-01-01

11b(-)CD8(+) and CD11b(+)Esam(hi) DC subsets, whereas CD11b(+)Esam(lo) DCs were not affected in conditional RhoA-deficient mice. Proteome analyses revealed a defective prosurvival pathway via PI3K/protein kinase B (Akt1)/Bcl-2-associated death promoter in the absence of RhoA. Taken together, our...... findings identify RhoA as a central regulator of DC homeostasis, and its deletion decreases DC numbers below critical thresholds for immune protection and homeostasis, causing aberrant compensatory DC proliferation....

Involvement of RhoA/Rho kinase signaling in VEGF-induced endothelial cell migration and angiogenesis in vitro

NARCIS (Netherlands)

Nieuw Amerongen, G.P. van; Koolwijk, P.; Versteilen, A.; Hinsbergh, V.W.M. van

2003-01-01

Objective - Growth factor-induced angiogenesis involves migration of endothelial cells (ECs) into perivascular areas and requires active remodeling of the endothelial F-actin cytoskeleton. The small GTPase RhoA previously has been implicated in vascular endothelial growth factor (VEGF)-induced

RhoA activation and nuclearization marks loss of chondrocyte phenotype in crosstalk with Wnt pathway.

Science.gov (United States)

Öztürk, Ece; Despot-Slade, Evelin; Pichler, Michael; Zenobi-Wong, Marcy

2017-11-15

De-differentiation comprises a major drawback for the use of autologous chondrocytes in cartilage repair. Here, we investigate the role of RhoA and canonical Wnt signaling in chondrocyte phenotype. Chondrocyte de-differentiation is accompanied by an upregulation and nuclear localization of RhoA. Effectors of canonical Wnt signaling including β-catenin and YAP/TAZ are upregulated in de-differentiating chondrocytes in a Rho-dependent manner. Inhibition of Rho activation with C3 transferase inhibits nuclear localization of RhoA, induces expression of chondrogenic markers on 2D and enhances the chondrogenic effect of 3D culturing. Upregulation of chondrogenic markers by Rho inhibition is accompanied by loss of canonical Wnt signaling markers in 3D or on 2D whereas treatment of chondrocytes with Wnt-3a abrogates this effect. However, induction of canonical Wnt signaling inhibits chondrogenic markers on 2D but enhances chondrogenic re-differentiation on 2D with C3 transferase or in 3D. These data provide insights on the context-dependent role of RhoA and Wnt signaling in de-differentiation and on mechanisms to induce chondrogenic markers for therapeutic approaches. Copyright © 2017 Elsevier Inc. All rights reserved.

Inclusive and semi-inclusive rho0 production in π-p interactions at 147 GeV/c

International Nuclear Information System (INIS)

Fong, D.; Heller, M.; Shapiro, A.M.; Widgoff, M.; Bruyant, F.; Bogert, D.; Johnson, M.; Burnstein, R.; Fu, C.; Petersen, D.; Robertson, M.; Rubin, H.; Sard, R.; Snyder, A.; Tortora, J.; Alyea, D.; Chien, C.-Y.; Lucas, P.; Pevsner, A.; Zdanis, R.; Brau, J.; Grunhaus, J.; Hafen, E.S.; Hulsizer, R.I.; Karshon, U.; Kistiakowsky, V.; Levy, A.; Napier, A.; Pless, I.A.; Trepagnier, P.C.; Wolfson, J.; Yamamoto, R.K.; Cohn, H.; Ou, T.C.; Plano, R.; Watts, T.; Brucker, E.; Koller, E.; Stamer, P.; Taylor, S.; Bugg, W.; Condo, G.; Handler, T.; Hart, E.; Kraybill, H.; Ljung, D.; Ludlam, T.; Taft, H.D.

1975-01-01

Data on inclusive and semi-inclusive rho 0 production in 147 GeV/c π - p interactions are presented. A total cross section of 7.3+-1.3 mb is found. Most of this cross section is found in the lower topology events ( 2 dependence of rho 0 production, sub(rho 0 ) per event, and the rho 0 /π + ratios are also discussed. (Auth.)

RhoA Drives T-Cell Activation and Encephalitogenic Potential in an Animal Model of Multiple Sclerosis

Directory of Open Access Journals (Sweden)

Alba Manresa-Arraut

2018-05-01

Full Text Available T-cells are known to be intimately involved in the pathogenesis of multiple sclerosis (MS and its animal model experimental autoimmune encephalomyelitis (EAE. T-cell activation is controlled by a range of intracellular signaling pathways regulating cellular responses such as proliferation, cytokine production, integrin expression, and migration. These processes are crucial for the T-cells’ ability to mediate inflammatory processes in autoimmune diseases such as MS. RhoA is a ubiquitously expressed small GTPase well described as a regulator of the actin cytoskeleton. It is essential for embryonic development and together with other Rho GTPases controls various cellular processes such as cell development, shaping, proliferation, and locomotion. However, the specific contribution of RhoA to these processes in T-cells in general, and in autoreactive T-cells in particular, has not been fully characterized. Using mice with a T-cell specific deletion of the RhoA gene (RhoAfl/flLckCre+, we investigated the role of RhoA in T-cell development, functionality, and encephalitogenic potential in EAE. We show that lack of RhoA specifically in T-cells results in reduced numbers of mature T-cells in thymus and spleen but normal counts in peripheral blood. EAE induction in RhoAfl/flLckCre+ mice results in significantly reduced disease incidence and severity, which coincides with a reduced CNS T-cell infiltration. Besides presenting reduced migratory capacity, both naïve and autoreactive effector T-cells from RhoAfl/flLckCre+ mice show decreased viability, proliferative capacity, and an activation profile associated with reduced production of Th1 pro-inflammatory cytokines. Our study demonstrates that RhoA is a central regulator of several archetypical T-cell responses, and furthermore points toward RhoA as a new potential therapeutic target in diseases such as MS, where T-cell activity plays a central role.

42 CFR 493.859 - Standard; ABO group and D (Rho) typing.

Science.gov (United States)

2010-10-01

... 42 Public Health 5 2010-10-01 2010-10-01 false Standard; ABO group and D (Rho) typing. 493.859 Section 493.859 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN..., Or Any Combination of These Tests § 493.859 Standard; ABO group and D (Rho) typing. (a) Failure to...

Proneural Transcription Factors Regulate Different Steps of Cortical Neuron Migration through Rnd-Mediated Inhibition of RhoA Signaling

Science.gov (United States)

Pacary, Emilie; Heng, Julian; Azzarelli, Roberta; Riou, Philippe; Castro, Diogo; Lebel-Potter, Mélanie; Parras, Carlos; Bell, Donald M.; Ridley, Anne J.; Parsons, Maddy; Guillemot, François

2011-01-01

Summary Little is known of the intracellular machinery that controls the motility of newborn neurons. We have previously shown that the proneural protein Neurog2 promotes the migration of nascent cortical neurons by inducing the expression of the atypical Rho GTPase Rnd2. Here, we show that another proneural factor, Ascl1, promotes neuronal migration in the cortex through direct regulation of a second Rnd family member, Rnd3. Both Rnd2 and Rnd3 promote neuronal migration by inhibiting RhoA signaling, but they control distinct steps of the migratory process, multipolar to bipolar transition in the intermediate zone and locomotion in the cortical plate, respectively. Interestingly, these divergent functions directly result from the distinct subcellular distributions of the two Rnd proteins. Because Rnd proteins also regulate progenitor divisions and neurite outgrowth, we propose that proneural factors, through spatiotemporal regulation of Rnd proteins, integrate the process of neuronal migration with other events in the neurogenic program. PMID:21435554

A GAP that Divides [version 1; referees: 3 approved

Directory of Open Access Journals (Sweden)

Angika Basant

2017-10-01

Full Text Available Cytokinesis in metazoan cells is mediated by an actomyosin-based contractile ring that assembles in response to activation of the small GTPase RhoA. The guanine nucleotide exchange factor that activates RhoA during cytokinesis, ECT-2, is highly regulated. In most metazoan cells, with the notable exception of the early Caenorhabditis elegans embryo, RhoA activation and furrow ingression require the centralspindlin complex. This exception is due to the existence of a parallel pathway for RhoA activation in C. elegans. Centralspindlin contains CYK-4 which contains a predicted Rho family GTPase-activating protein (GAP domain. The function of this domain has been the subject of considerable debate. Some publications suggest that the GAP domain promotes RhoA activation (for example, Zhang and Glotzer, 2015; Loria, Longhini and Glotzer, 2012, whereas others suggest that it functions to inactivate the GTPase Rac1 (for example, Zhuravlev et al., 2017. Here, we review the mechanisms underlying RhoA activation during cytokinesis, primarily focusing on data in C. elegans. We highlight the importance of considering the parallel pathway for RhoA activation and detailed analyses of cyk-4 mutant phenotypes when evaluating the role of the GAP domain of CYK-4.

Molecular identification of Trichuris vulpis and Trichuris suis isolated from different hosts.

Science.gov (United States)

Cutillas, Cristina; de Rojas, Manuel; Ariza, Concepción; Ubeda, José Manuel; Guevara, Diego

2007-01-01

Trichuris suis was isolated from the cecum of two different hosts (Sus scrofa domestica -- swine and Sus scrofa scrofa -- wild boar) and Trichuris vulpis from dogs in Sevilla, Spain. Genomic DNA was isolated and internal transcribed spacers (ITS)1-5.8S-ITS2 segment from the ribosomal DNA (rDNA) was amplified and sequenced using polymerase chain reaction techniques. The sequence of T. suis from both hosts was 1,396 bp in length while that of T. vulpis was 1,044 bp. ITS1 of both populations isolated of T. suis was 661 nucleotides in length, while the ITS2 was 534 nucleotides in length. Furthermore, the ITS1 of T. vulpis was 410 nucleotides in length, while the ITS2 was 433 nucleotides in length. One hundred fifty-four nucleotides were observed along the 5.8S gene of T. suis and T. vulpis. Intraindividual and intraspecific variations were detected in the rDNA of both species. The presence of microsatellites was observed in all the individuals assayed. Sequence analysis of the ITSs and the 5.8S gene has demonstrated no sequence differences between T. suis isolated from both hosts (S. scrofa domestica -- swine and S. scrofa scrofa -- wild boar). Nevertheless, clear differences were detected between the ITS1 and ITS2 of T. suis and T. vulpis. Furthermore, a comparative molecular analysis between both species and the previously published ITS1-5.8S-ITS2 sequence data of Trichuris ovis, Trichuris leporis, Trichuris muris, Trichuris arvicolae, and Trichuris skrjabini was carried out. A common homology zone was detected in the ITS1 sequence of all species of trichurids.

BRAF and RAS oncogenes regulate Rho GTPase pathways to mediate migration and invasion properties in human colon cancer cells: a comparative study

Directory of Open Access Journals (Sweden)

Shirasawa Senji

2011-09-01

Full Text Available Abstract Background Colorectal cancer is a common disease that involves genetic alterations, such as inactivation of tumour suppressor genes and activation of oncogenes. Among them are RAS and BRAF mutations, which rarely coexist in the same tumour. Individual members of the Rho (Ras homology GTPases contribute with distinct roles in tumour cell morphology, invasion and metastasis. The aim of this study is to dissect cell migration and invasion pathways that are utilised by BRAFV600E as compared to KRASG12V and HRASG12V oncoproteins. In particular, the role of RhoA (Ras homolog gene family, member A, Rac1 (Ras-related C3 botulinum toxin substrate 1 and Cdc42 (cell division cycle 42 in cancer progression induced by each of the three oncogenes is described. Methods Colon adenocarcinoma cells with endogenous as well as ectopically expressed or silenced oncogenic mutations of BRAFV600E, KRASG12V and HRASG12V were employed. Signalling pathways and Rho GTPases were inhibited with specific kinase inhibitors and siRNAs. Cell motility and invasion properties were correlated with cytoskeletal properties and Rho GTPase activities. Results Evidence presented here indicate that BRAFV600E significantly induces cell migration and invasion properties in vitro in colon cancer cells, at least in part through activation of RhoA GTPase. The relationship established between BRAFV600E and RhoA activation is mediated by the MEK-ERK pathway. In parallel, KRASG12V enhances the ability of colon adenocarcinoma cells Caco-2 to migrate and invade through filopodia formation and PI3K-dependent Cdc42 activation. Ultimately increased cell migration and invasion, mediated by Rac1, along with the mesenchymal morphology obtained through the Epithelial-Mesenchymal Transition (EMT were the main characteristics rendered by HRASG12V in Caco-2 cells. Moreover, BRAF and KRAS oncogenes are shown to cooperate with the TGFβ-1 pathway to provide cells with additional transforming

Triptolide disrupts the actin-based Sertoli-germ cells adherens junctions by inhibiting Rho GTPases expression

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiang; Zhao, Fang [Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing 210009 (China); Lv, Zhong-ming; Shi, Wei-qin [Jiangsu Provincial Center for Disease Control and Prevention, Nanjing (China); Zhang, Lu-yong, E-mail: lyzhang@cpu.edu.cn [Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing 210009 (China); Key Laboratory of Drug Quality Control and Pharmacovigilance, China Pharmaceutical University, Nanjing (China); State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009 (China); Yan, Ming, E-mail: brookming@cpu.edu.cn [Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing 210009 (China)

2016-11-01

Triptolide (TP), derived from the medicinal plant Triterygium wilfordii Hook. f. (TWHF), is a diterpene triepoxide with variety biological and pharmacological activities. However, TP has been restricted in clinical application due to its narrow therapeutic window especially in reproductive system. During spermatogenesis, Sertoli cell cytoskeleton plays an essential role in facilitating germ cell movement and cell-cell actin-based adherens junctions (AJ). At Sertoli cell-spermatid interface, the anchoring device is a kind of AJ, known as ectoplasmic specializations (ES). In this study, we demonstrate that β-actin, an important component of cytoskeleton, has been significantly down-regulated after TP treatment. TP can inhibit the expression of Rho GTPase such as, RhoA, RhoB, Cdc42 and Rac1. Downstream of Rho GTPase, Rho-associated protein kinase (ROCKs) gene expressions were also suppressed by TP. F-actin immunofluorescence proved that TP disrupts Sertoli cells cytoskeleton network. As a result of β-actin down-regulation, TP treatment increased expression of testin, which indicating ES has been disassembled. In summary, this report illustrates that TP induces cytoskeleton dysfunction and disrupts cell-cell adherens junctions via inhibition of Rho GTPases. - Highlights: • Triptolide induced the disruption of Sertoli-germ cell adherens junction. • Rho GTPases expression and actin dynamics have been suppressed by triptolide. • Actin-based adherens junction is a potential antifertility target of triptolide. • Rho-Rock is involved in the regulation of actin dynamics.

Triptolide disrupts the actin-based Sertoli-germ cells adherens junctions by inhibiting Rho GTPases expression

International Nuclear Information System (INIS)

Wang, Xiang; Zhao, Fang; Lv, Zhong-ming; Shi, Wei-qin; Zhang, Lu-yong; Yan, Ming

2016-01-01

Triptolide (TP), derived from the medicinal plant Triterygium wilfordii Hook. f. (TWHF), is a diterpene triepoxide with variety biological and pharmacological activities. However, TP has been restricted in clinical application due to its narrow therapeutic window especially in reproductive system. During spermatogenesis, Sertoli cell cytoskeleton plays an essential role in facilitating germ cell movement and cell-cell actin-based adherens junctions (AJ). At Sertoli cell-spermatid interface, the anchoring device is a kind of AJ, known as ectoplasmic specializations (ES). In this study, we demonstrate that β-actin, an important component of cytoskeleton, has been significantly down-regulated after TP treatment. TP can inhibit the expression of Rho GTPase such as, RhoA, RhoB, Cdc42 and Rac1. Downstream of Rho GTPase, Rho-associated protein kinase (ROCKs) gene expressions were also suppressed by TP. F-actin immunofluorescence proved that TP disrupts Sertoli cells cytoskeleton network. As a result of β-actin down-regulation, TP treatment increased expression of testin, which indicating ES has been disassembled. In summary, this report illustrates that TP induces cytoskeleton dysfunction and disrupts cell-cell adherens junctions via inhibition of Rho GTPases. - Highlights: • Triptolide induced the disruption of Sertoli-germ cell adherens junction. • Rho GTPases expression and actin dynamics have been suppressed by triptolide. • Actin-based adherens junction is a potential antifertility target of triptolide. • Rho-Rock is involved in the regulation of actin dynamics.

Cytosolic nucleotides block and regulate the Arabidopsis vacuolar anion channel AtALMT9.

Science.gov (United States)

Zhang, Jingbo; Martinoia, Enrico; De Angeli, Alexis

2014-09-12

The aluminum-activated malate transporters (ALMTs) form a membrane protein family exhibiting different physiological roles in plants, varying from conferring tolerance to environmental Al(3+) to the regulation of stomatal movement. The regulation of the anion channels of the ALMT family is largely unknown. Identifying intracellular modulators of the activity of anion channels is fundamental to understanding their physiological functions. In this study we investigated the role of cytosolic nucleotides in regulating the activity of the vacuolar anion channel AtALMT9. We found that cytosolic nucleotides modulate the transport activity of AtALMT9. This modulation was based on a direct block of the pore of the channel at negative membrane potentials (open channel block) by the nucleotide and not by a phosphorylation mechanism. The block by nucleotides of AtALMT9-mediated currents was voltage dependent. The blocking efficiency of intracellular nucleotides increased with the number of phosphate groups and ATP was the most effective cellular blocker. Interestingly, the ATP block induced a marked modification of the current-voltage characteristic of AtALMT9. In addition, increased concentrations of vacuolar anions were able to shift the ATP block threshold to a more negative membrane potential. The block of AtALMT9-mediated anion currents by ATP at negative membrane potentials acts as a gate of the channel and vacuolar anion tune this gating mechanism. Our results suggest that anion transport across the vacuolar membrane in plant cells is controlled by cytosolic nucleotides and the energetic status of the cell. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Cytosolic Nucleotides Block and Regulate the Arabidopsis Vacuolar Anion Channel AtALMT9*

Science.gov (United States)

Zhang, Jingbo; Martinoia, Enrico; De Angeli, Alexis

2014-01-01

The aluminum-activated malate transporters (ALMTs) form a membrane protein family exhibiting different physiological roles in plants, varying from conferring tolerance to environmental Al3+ to the regulation of stomatal movement. The regulation of the anion channels of the ALMT family is largely unknown. Identifying intracellular modulators of the activity of anion channels is fundamental to understanding their physiological functions. In this study we investigated the role of cytosolic nucleotides in regulating the activity of the vacuolar anion channel AtALMT9. We found that cytosolic nucleotides modulate the transport activity of AtALMT9. This modulation was based on a direct block of the pore of the channel at negative membrane potentials (open channel block) by the nucleotide and not by a phosphorylation mechanism. The block by nucleotides of AtALMT9-mediated currents was voltage dependent. The blocking efficiency of intracellular nucleotides increased with the number of phosphate groups and ATP was the most effective cellular blocker. Interestingly, the ATP block induced a marked modification of the current-voltage characteristic of AtALMT9. In addition, increased concentrations of vacuolar anions were able to shift the ATP block threshold to a more negative membrane potential. The block of AtALMT9-mediated anion currents by ATP at negative membrane potentials acts as a gate of the channel and vacuolar anion tune this gating mechanism. Our results suggest that anion transport across the vacuolar membrane in plant cells is controlled by cytosolic nucleotides and the energetic status of the cell. PMID:25028514

Sodium and T1rho MRI for molecular and diagnostic imaging of articular cartilage.

Science.gov (United States)

Borthakur, Arijitt; Mellon, Eric; Niyogi, Sampreet; Witschey, Walter; Kneeland, J Bruce; Reddy, Ravinder

2006-11-01

In this article, both sodium magnetic resonance (MR) and T1rho relaxation mapping aimed at measuring molecular changes in cartilage for the diagnostic imaging of osteoarthritis are reviewed. First, an introduction to structure of cartilage, its degeneration in osteoarthritis (OA) and an outline of diagnostic imaging methods in quantifying molecular changes and early diagnostic aspects of cartilage degeneration are described. The sodium MRI section begins with a brief overview of the theory of sodium NMR of biological tissues and is followed by a section on multiple quantum filters that can be used to quantify both bi-exponential relaxation and residual quadrupolar interaction. Specifically, (i) the rationale behind the use of sodium MRI in quantifying proteoglycan (PG) changes, (ii) validation studies using biochemical assays, (iii) studies on human OA specimens, (iv) results on animal models and (v) clinical imaging protocols are reviewed. Results demonstrating the feasibility of quantifying PG in OA patients and comparison with that in healthy subjects are also presented. The section concludes with the discussion of advantages and potential issues with sodium MRI and the impact of new technological advancements (e.g. ultra-high field scanners and parallel imaging methods). In the theory section on T1rho, a brief description of (i) principles of measuring T1rho relaxation, (ii) pulse sequences for computing T1rho relaxation maps, (iii) issues regarding radio frequency power deposition, (iv) mechanisms that contribute to T1rho in biological tissues and (v) effects of exchange and dipolar interaction on T1rho dispersion are discussed. Correlation of T1rho relaxation rate with macromolecular content and biomechanical properties in cartilage specimens subjected to trypsin and cytokine-induced glycosaminoglycan depletion and validation against biochemical assay and histopathology are presented. Experimental T1rho data from osteoarthritic specimens, animal models

Evolution of life cycle, colony morphology, and host specificity in the family Hydractiniidae (Hydrozoa, Cnidaria).

Science.gov (United States)

Miglietta, Maria Pia; Cunningham, Clifford W

2012-12-01

Biased transitions are common throughout the tree of life. The class hydrozoa is no exception, having lost the feeding medusa stage at least 70 times. The family hydractiniidae includes one lineage with pelagic medusae (Podocoryna) and several without (e.g., Hydractinia). The benthic colony stage also varies widely in host specificity and in colony form. The five-gene phylogeny presented here requires multiple transitions between character states for medusae, host specificity, and colony phenotype. Significant phylogenetic correlations exist between medusoid form, colony morphology, and host specificity. Species with nonfeeding medusae are usually specialized on a single host type, and reticulate colonies are correlated with nonmotile hosts. The history of feeding medusae is less certain. Podocoryna is nested within five lineages lacking medusae. This requires either repeated losses of medusae, or the remarkable re-evolution of a feeding medusa after at least 150 million years. Traditional ancestral reconstruction favors medusa regain, but a likelihood framework testing biased transitions cannot distinguish between multiple losses versus regain. A hypothesis of multiple losses of feeding medusae requires transient selection pressure favoring such a loss. Populations of species with feeding medusae are always locally rare and lack of feeding medusae does not result in restricted species distribution around the world. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

The Impact of Host Family Relations and Length of Stay on Adolescent Identity Expression during Study Abroad

Science.gov (United States)

Grieve, Averil Marie

2015-01-01

This study focuses on the relationships between host family success, social integration, length of stay and acquisition of adolescent language by students on extended international homestay programmes. Degree of adolescent language acquisition and integration is measured by use of two hallmarks of adolescent language: markers of approximation…

Shifts in diversification rates and host jump frequencies shaped the diversity of host range among Sclerotiniaceae fungal plant pathogens.

Science.gov (United States)

Navaud, Olivier; Barbacci, Adelin; Taylor, Andrew; Clarkson, John P; Raffaele, Sylvain

2018-03-01

The range of hosts that a parasite can infect in nature is a trait determined by its own evolutionary history and that of its potential hosts. However, knowledge on host range diversity and evolution at the family level is often lacking. Here, we investigate host range variation and diversification trends within the Sclerotiniaceae, a family of Ascomycete fungi. Using a phylogenetic framework, we associate diversification rates, the frequency of host jump events and host range variation during the evolution of this family. Variations in diversification rate during the evolution of the Sclerotiniaceae define three major macro-evolutionary regimes with contrasted proportions of species infecting a broad range of hosts. Host-parasite cophylogenetic analyses pointed towards parasite radiation on distant hosts long after host speciation (host jump or duplication events) as the dominant mode of association with plants in the Sclerotiniaceae. The intermediate macro-evolutionary regime showed a low diversification rate, high frequency of duplication events and the highest proportion of broad host range species. Our findings suggest that the emergence of broad host range fungal pathogens results largely from host jumps, as previously reported for oomycete parasites, probably combined with low speciation rates. These results have important implications for our understanding of fungal parasites evolution and are of particular relevance for the durable management of disease epidemics. © 2018 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

Search for the Decay B^0 -> a^\\pm_1 \\rho^\\mp

Energy Technology Data Exchange (ETDEWEB)

Aubert, B.

2006-05-10

The authors present a search for the rare B-meson decay B{sup 0} {yields} {alpha}{sub 1}{sup {+-}}{rho}{sup {-+}} with {alpha}{sub 1}{sup {+-}} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup {+-}}. We use (110 {+-} 1.2) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEp-II asymmetric-energy B Factory at SLAC. They obtain an upper limit of 30 x 10{sup -6} (90% C.L.) for the branching fraction product {Beta}(B{sup 0} {yields} {alpha}{sub 1}{sup {+-}}{rho}{sup {-+}}) {Beta}({alpha}{sub 1}{sup {+-}} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup {+-}}), where they assume that the {alpha}{sub 1}{sup {+-}} decays exclusively to {rho}{sup 0}{pi}{sup {+-}}.

Rho, a Fraction From Rhodiola crenulate, Ameliorates Hepatic Steatosis in Mice Models

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Qin Yi

2018-03-01

Full Text Available The prevalence of non-alcoholic fatty liver disease (NAFLD, which is developed from hepatic steatosis, is increasing worldwide. However, no specific drugs for NAFLD have been approved yet. To observe the effects of Rho, a fraction from Rhodiola crenulate, on non-alcoholic hepatic steatosis, three mouse models with characteristics of NAFLD were used including high-fat diet (HFD-induced obesity (DIO mice, KKAy mice, and HFD combined with tetracycline stimulated Model-T mice. Hepatic lipid accumulation was determined via histopathological analysis and/or hepatic TG determination. The responses to insulin were evaluated by insulin tolerance test (ITT, glucose tolerance test (GTT, and hyperinsulinemic-euglycemic clamp, respectively. The pathways involved in hepatic lipid metabolism were observed via western-blot. Furthermore, the liver microcirculation was observed by inverted microscopy. The HPLC analysis indicated that the main components of Rho were flavan polymers. The results of histopathological analysis showed that Rho could ameliorate hepatic steatosis in DIO, KKAy, and Model-T hepatic steatosis mouse models, respectively. After Rho treatment in DIO mice, insulin resistance was improved with increasing glucose infusion rate (GIR in hyperinsulinemic-euglycemic clamp, and decreasing areas under the blood glucose-time curve (AUC in both ITT and GTT; the pathways involved in fatty acid uptake and de novo lipogenesis were both down-regulated, respectively. However, the pathways involved in beta-oxidation and VLDL-export on hepatic steatosis were not changed significantly. The liver microcirculation disturbances were also improved by Rho in DIO mice. These results suggest that Rho is a lead nature product for hepatic steatosis treatment. The mechanism is related to enhancing insulin sensitivity, suppressing fatty acid uptake and inhibiting de novo lipogenesis in liver.

A family of diverse Kunitz inhibitors from Echinococcus granulosus potentially involved in host-parasite cross-talk.

Science.gov (United States)

González, Silvia; Fló, Martín; Margenat, Mariana; Durán, Rosario; González-Sapienza, Gualberto; Graña, Martín; Parkinson, John; Maizels, Rick M; Salinas, Gustavo; Alvarez, Beatriz; Fernández, Cecilia

2009-09-17

The cestode Echinococcus granulosus, the agent of hydatidosis/echinococcosis, is remarkably well adapted to its definitive host. However, the molecular mechanisms underlying the successful establishment of larval worms (protoscoleces) in the dog duodenum are unknown. With the aim of identifying molecules participating in the E. granulosus-dog cross-talk, we surveyed the transcriptomes of protoscoleces and protoscoleces treated with pepsin at pH 2. This analysis identified a multigene family of secreted monodomain Kunitz proteins associated mostly with pepsin/H(+)-treated worms, suggesting that they play a role at the onset of infection. We present the relevant molecular features of eight members of the E. granulosus Kunitz family (EgKU-1 - EgKU-8). Although diverse, the family includes three pairs of close paralogs (EgKU-1/EgKU-4; EgKU-3/EgKU-8; EgKU-6/EgKU-7), which would be the products of recent gene duplications. In addition, we describe the purification of EgKU-1 and EgKU-8 from larval worms, and provide data indicating that some members of the family (notably, EgKU-3 and EgKU-8) are secreted by protoscoleces. Detailed kinetic studies with native EgKU-1 and EgKU-8 highlighted their functional diversity. Like most monodomain Kunitz proteins, EgKU-8 behaved as a slow, tight-binding inhibitor of serine proteases, with global inhibition constants (K(I) (*)) versus trypsins in the picomolar range. In sharp contrast, EgKU-1 did not inhibit any of the assayed peptidases. Interestingly, molecular modeling revealed structural elements associated with activity in Kunitz cation-channel blockers. We propose that this family of inhibitors has the potential to act at the E. granulosus-dog interface and interfere with host physiological processes at the initial stages of infection.

Expression loss and revivification of RhoB gene in ovary carcinoma carcinogenesis and development.

Science.gov (United States)

Liu, Yingwei; Song, Na; Ren, Kexing; Meng, Shenglan; Xie, Yao; Long, Qida; Chen, Xiancheng; Zhao, Xia

2013-01-01

RhoB, a member of small GTPases belonging to the Ras protein superfamily, might have a suppressive activity in cancer progression. Here, expression of RhoB gene was evaluated in human benign, borderline and malignant ovary tumors by immunostaining, with normal ovary tissue as control. Malignant tumors were assessed according to Federation Internationale de Gynecologie Obstetrique (FIGO) guidelines and classified in stage I-IV. Revivification of RhoB gene was investigated by analyzing the effect of histone deacetylase (HDAC) inhibitor trichostatin (TSA) and methyltransferase inhibitor 5-azacytidine (5-Aza) on ovarian cancer cells via RT-PCR and western blot. Apoptosis of ovary cancer cells was detected using flowcytometry and fluorescence microscopy. Subsequently, RhoB expression is detected in normal ovary epithelium, borderline tumors, and decreases significantly or lost in the majority of ovarian cancer specimen (Pcancer cells, but 5-Aza couldn't. Interference into Revivification of RhoB gene results in reduction of ovary carcinoma cell apoptosis. It is proposed that loss of RhoB expression occurs frequently in ovary carcinogenesis and progression and its expression could be regulated by histone deacetylation but not by promoter hypermethylation, which may serve as a prospective gene treatment target for the patients with ovarian malignancy not responding to standard therapies.

The Poxvirus C7L Host Range Factor Superfamily

OpenAIRE

Liu, Jia; Rothenburg, Stefan; McFadden, Grant

2012-01-01

Host range factors, expressed by the poxvirus family, determine the host tropism of species, tissue, and cell specificity. C7L family members exist in the genomes of most sequenced mammalian poxviruses, suggesting an evolutionarily conserved effort adapting to the hosts. In general, C7L orthologs influence the host tropism in mammalian cell culture, and for some poxviruses it is essential for the complete viral life cycle in vitro and in vivo. The C7L family members lack obvious sequence homo...

Exclusive $\\rho^0$ Meson Photoproduction with a Leading Neutron at HERA

CERN Document Server

Andreev, V.; Begzsuren, K.; Belousov, A.; Bolz, A.; Boudry, V.; Brandt, G.; Brisson, V.; Britzger, D.; Buniatyan, A.; Bylinkin, A.; Bystritskaya, L.; Campbell, A.J.; Cantun Avila, K.B.; Cerny, K.; Chekelian, V.; Contreras, J.G.; Cvach, J.; Dainton, J.B.; Daum, K.; Diaconu, C.; Dobre, M.; Dodonov, V.; Eckerlin, G.; Egli, S.; Elsen, E.; Favart, L.; Fedotov, A.; Feltesse, J.; Ferencei, J.; Fleischer, M.; Fomenko, A.; Gabathuler, E.; Gayler, J.; Ghazaryan, S.; Goerlich, L.; Gogitidze, N.; Gouzevitch, M.; Grab, C.; Grebenyuk, A.; Greenshaw, T.; Grindhammer, G.; Haidt, D.; Henderson, R.C.W.; Hladký, J.; Hoffmann, D.; Horisberger, R.; Hreus, T.; Huber, F.; Jacquet, M.; Janssen, X.; Jung, H.; Kapichine, M.; Kiesling, C.; Klein, M.; Kleinwort, C.; Kogler, R.; Kostka, P.; Kretzschmar, J.; Krüger, K.; Landon, M.P.J.; Lange, W.; Laycock, P.; Lebedev, A.; Levonian, S.; Lipka, K.; List, B.; List, J.; Lobodzinski, B.; Malinovski, E.; Martyn, H.-U.; Maxfield, S.J.; Mehta, A.; Meyer, A.B.; Meyer, H.; Meyer, J.; Mikocki, S.; Morozov, A.; Müller, K.; Naumann, Th.; Newman, P.R.; Niebuhr, C.; Nowak, G.; Olsson, J.E.; Ozerov, D.; Pascaud, C.; Patel, G.D.; Perez, E.; Petrukhin, A.; Picuric, I.; Pirumov, H.; Pitzl, D.; Plačakytė, R.; Pokorny, B.; Polifka, R.; Povh, B.; Radescu, V.; Raicevic, N.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Rusakov, S.; Šálek, D.; Sankey, D.P.C.; Sauter, M.; Sauvan, E.; Schmitt, S.; Schoeffel, L.; Schöning, A.; Sefkow, F.; Shushkevich, S.; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, A.; Steder, M.; Stella, B.; Straumann, U.; Sykora, T.; Thompson, P.D.; Traynor, D.; Truöl, P.; Tsakov, I.; Tseepeldorj, B.; Turnau, J.; Valkárová, A.; Vallée, C.; Van Mechelen, P.; Vazdik, Y.; Wegener, D.; Wünsch, E.; Žáček, J.; Zhang, Z.; Žlebčík, R.; Zohrabyan, H.; Zomer, F.

2016-01-23

A first measurement is presented of exclusive photoproduction of $\\rho^0$ mesons associated with leading neutrons at HERA. The data were taken with the H1 detector in the years $2006$ and $2007$ at a centre-of-mass energy of $\\sqrt{s}=319$ GeV and correspond to an integrated luminosity of $1.16$ pb$^{-1}$. The $\\rho^0$ mesons with transverse momenta $p_T0.35$, are detected in the Forward Neutron Calorimeter. The phase space of the measurement is defined by the photon virtuality $Q^2 < 2$ GeV$^2$, the total energy of the photon-proton system $20 < W_{\\gamma p} < 100$ GeV and the polar angle of the leading neutron $\\theta_n < 0.75$ mrad. The cross section of the reaction $\\gamma p \\to \\rho^0 n \\pi^+$ is measured as a function of several variables. The data are interpreted in terms of a double peripheral process, involving pion exchange at the proton vertex followed by elastic photoproduction of a $\\rho^0$ meson on the virtual pion. In the framework of one-pion-exchange dominance the elastic cross se...

Mitotic evolution of Plasmodium falciparum shows a stable core genome but recombination in antigen families.

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Selina E R Bopp

Full Text Available Malaria parasites elude eradication attempts both within the human host and across nations. At the individual level, parasites evade the host immune responses through antigenic variation. At the global level, parasites escape drug pressure through single nucleotide variants and gene copy amplification events conferring drug resistance. Despite their importance to global health, the rates at which these genomic alterations emerge have not been determined. We studied the complete genomes of different Plasmodium falciparum clones that had been propagated asexually over one year in the presence and absence of drug pressure. A combination of whole-genome microarray analysis and next-generation deep resequencing (totaling 14 terabases revealed a stable core genome with only 38 novel single nucleotide variants appearing in seventeen evolved clones (avg. 5.4 per clone. In clones exposed to atovaquone, we found cytochrome b mutations as well as an amplification event encompassing the P. falciparum multidrug resistance associated protein (mrp1 on chromosome 1. We observed 18 large-scale (>1 kb on average deletions of telomere-proximal regions encoding multigene families, involved in immune evasion (9.5×10(-6 structural variants per base pair per generation. Six of these deletions were associated with chromosomal crossovers generated during mitosis. We found only minor differences in rates between genetically distinct strains and between parasites cultured in the presence or absence of drug. Using these derived mutation rates for P. falciparum (1.0-9.7×10(-9 mutations per base pair per generation, we can now model the frequency at which drug or immune resistance alleles will emerge under a well-defined set of assumptions. Further, the detection of mitotic recombination events in var gene families illustrates how multigene families can arise and change over time in P. falciparum. These results will help improve our understanding of how P. falciparum

Mitotic Evolution of Plasmodium falciparum Shows a Stable Core Genome but Recombination in Antigen Families

Science.gov (United States)

Bopp, Selina E. R.; Manary, Micah J.; Bright, A. Taylor; Johnston, Geoffrey L.; Dharia, Neekesh V.; Luna, Fabio L.; McCormack, Susan; Plouffe, David; McNamara, Case W.; Walker, John R.; Fidock, David A.; Denchi, Eros Lazzerini; Winzeler, Elizabeth A.

2013-01-01

Malaria parasites elude eradication attempts both within the human host and across nations. At the individual level, parasites evade the host immune responses through antigenic variation. At the global level, parasites escape drug pressure through single nucleotide variants and gene copy amplification events conferring drug resistance. Despite their importance to global health, the rates at which these genomic alterations emerge have not been determined. We studied the complete genomes of different Plasmodium falciparum clones that had been propagated asexually over one year in the presence and absence of drug pressure. A combination of whole-genome microarray analysis and next-generation deep resequencing (totaling 14 terabases) revealed a stable core genome with only 38 novel single nucleotide variants appearing in seventeen evolved clones (avg. 5.4 per clone). In clones exposed to atovaquone, we found cytochrome b mutations as well as an amplification event encompassing the P. falciparum multidrug resistance associated protein (mrp1) on chromosome 1. We observed 18 large-scale (>1 kb on average) deletions of telomere-proximal regions encoding multigene families, involved in immune evasion (9.5×10−6 structural variants per base pair per generation). Six of these deletions were associated with chromosomal crossovers generated during mitosis. We found only minor differences in rates between genetically distinct strains and between parasites cultured in the presence or absence of drug. Using these derived mutation rates for P. falciparum (1.0–9.7×10−9 mutations per base pair per generation), we can now model the frequency at which drug or immune resistance alleles will emerge under a well-defined set of assumptions. Further, the detection of mitotic recombination events in var gene families illustrates how multigene families can arise and change over time in P. falciparum. These results will help improve our understanding of how P. falciparum evolves to

Inclusive rho0 production in anti νsub(μ)p charged current interactions

International Nuclear Information System (INIS)

Graessler, H.; Lanske, D.; Schulte, R.; Barnham, K.W.J.; Clayton, E.F.; Hamisi, F.; Miller, D.B.; Mobayyen, M.M.; Corrigan, G.; Myatt, G.; Radojicic, D.; Saitta, B.; Wells, J.

1986-01-01

Inclusive rho 0 production has been studied in antineutrino-proton charged current interactions, using a sample of 3340 events obtained in BEBC filled with hydrogen and exposed to the CERN wideband antineutrino beam. An average multiplicity of 0.11+-0.02 rho 0 per event at a mean hadronic mass W of 4.2 GeV is observed. The rho 0 production characteristics are determined as functions of psub(T), chisub(F), and z. The ratio rho 0 /'π 0 ' is found to be low at small z values consistent with centrally produced pions coming mainly from resonances. At large z values this ratio approaches 0.45+-0.15 which is compatible with a vector/pseudoscalar meson direct production ratio of one. The results are compared with those obtained from neutrino-proton interactions in the same experimental set-up. (orig.)

Regulation of white and brown adipocyte differentiation by RhoGAP DLC1.

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Choon Kiat Sim

Full Text Available Adipose tissues constitute an important component of metabolism, the dysfunction of which can cause obesity and type II diabetes. Here we show that differentiation of white and brown adipocytes requires Deleted in Liver Cancer 1 (DLC1, a Rho GTPase Activating Protein (RhoGAP previously studied for its function in liver cancer. We identified Dlc1 as a super-enhancer associated gene in both white and brown adipocytes through analyzing the genome-wide binding profiles of PPARγ, the master regulator of adipogenesis. We further observed that Dlc1 expression increases during differentiation, and knockdown of Dlc1 by siRNA in white adipocytes reduces the formation of lipid droplets and the expression of fat marker genes. Moreover, knockdown of Dlc1 in brown adipocytes reduces expression of brown fat-specific genes and diminishes mitochondrial respiration. Dlc1-/- knockout mouse embryonic fibroblasts show a complete inability to differentiate into adipocytes, but this phenotype can be rescued by inhibitors of Rho-associated kinase (ROCK and filamentous actin (F-actin, suggesting the involvement of Rho pathway in DLC1-regulated adipocyte differentiation. Furthermore, PPARγ binds to the promoter of Dlc1 gene to regulate its expression during both white and brown adipocyte differentiation. These results identify DLC1 as an activator of white and brown adipocyte differentiation, and provide a molecular link between PPARγ and Rho pathways.

Mycobacterium tuberculosis Rho is an NTPase with distinct kinetic properties and a novel RNA-binding subdomain.

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Anirban Mitra

Full Text Available Two mechanisms--factor independent and dependent termination--ensure the completion of RNA synthesis in eubacteria. Factor-dependent mechanism relies on the Rho protein to terminate transcription by interacting with RNA polymerase. Although well studied in Escherichia coli, the properties of the Rho homologs from most bacteria are not known. The rho gene is unusually large in genus Mycobacterium and other members of actinobacteria, having ∼150 additional residues towards the amino terminal end. We describe the distinct properties of Rho from Mycobacterium tuberculosis. It is an NTPase with a preference for purine nucleoside triphosphates with kinetic properties different from E. coli homolog and an ability to use various RNA substrates. The N-terminal subdomain of MtbRho can bind to RNA by itself, and appears to contribute to the interaction of the termination factor with RNAs. Furthermore, the interaction with RNA induces changes in conformation and oligomerization of MtbRho.

Nucleotide diversity analysis of three major bacterial blight resistance genes in rice.

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Waikhom Bimolata

Full Text Available Nucleotide sequence polymorphisms among R gene alleles influence the process of co-evolutionary interaction between host and pathogen by shaping the response of host plants towards invading pathogens. Here, we present the DNA sequence polymorphisms and diversities present among natural alleles of three rice bacterial blight resistance genes, Xa21, Xa26 and xa5. The diversity was examined across different wild relatives and cultivars of Oryza species. Functional significance of selected alleles was evaluated through semi-quantitative reverse transcription polymerase chain reaction and real time PCR. The greatest nucleotide diversity and singleton variable sites (SVS were present in Xa26 (π = 0.01958; SVS = 182 followed by xa5 and Xa21 alleles. The highest frequency of single nucleotide polymorphisms were observed in Xa21 alleles and least in xa5. Transition bias was observed in all the genes and 'G' to 'A' transitions were more favored than other form of transitions. Neutrality tests failed to show the presence of selection at these loci, though negative Tajima's D values indicate the presence of a rare form of polymorphisms. At the interspecies level, O. nivara exhibited more diversity than O. sativa. We have also identified two nearly identical resistant alleles of xa5 and two sequentially identical alleles of Xa21. The alleles of xa5 showed basal levels of expression while Xa21 alleles were functionally not expressed.

Activation of G protein-coupled estrogen receptor 1 induces coronary artery relaxation via Epac/Rap1-mediated inhibition of RhoA/Rho kinase pathway in parallel with PKA.

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Xuan Yu

Full Text Available Previously, we reported that cAMP/PKA signaling is involved in GPER-mediated coronary relaxation by activating MLCP via inhibition of RhoA pathway. In the current study, we tested the hypothesis that activation of GPER induces coronary artery relaxation via inhibition of RhoA/Rho kinase pathway by cAMP downstream targets, exchange proteins directly activated by cAMP (Epac as well as PKA. Our results show that Epac inhibitors, brefeldin A (BFA, 50 μM, or ESI-09 (20 μM, or CE3F4 (100 μM, all partially inhibited porcine coronary artery relaxation response to the selective GPER agonist, G-1 (0.3-3 μM; while concurrent administration of BFA and PKI (5 μM, a PKA inhibitor, almost completely blocked the relaxation effect of G-1. The Epac specific agonist, 8-CPT-2Me-cAMP (007, 1-100 μM, induced a concentration-dependent relaxation response. Furthermore, the activity of Ras-related protein 1 (Rap1 was up regulated by G-1 (1 μM treatment of porcine coronary artery smooth muscle cells (CASMCs. Phosphorylation of vasodilator-stimulated phosphoprotein (p-VASP was elevated by G-1 (1 μM treatment, but not by 007 (50 μM; and the effect of G-1 on p-VASP was blocked by PKI, but not by ESI-09, an Epac antagonist. RhoA activity was similarly down regulated by G-1 and 007, whereas ESI-09 restored most of the reduced RhoA activity by G-1 treatment. Furthermore, G-1 decreased PGF2α-induced p-MYPT1, which was partially reversed with either ESI-09 or PKI; whereas, concurrent administration of ESI-09 and PKI totally prevented the inhibitory effect of G-1. The inhibitory effects of G-1 on p- MLC levels in CASMCs were mostly restored by either ESI-09 or PKI. These results demonstrate that activation of GPER induces coronary artery relaxation via concurrent inhibition of RhoA/Rho kinase by Epac/Rap1 and PKA. GPER could be a potential drug target for preventing and treating cardiovascular diseases.

Human Mammary Epithelial Cell Transformation by Rho GTPase Through a Novel Mechanism

Science.gov (United States)

2009-08-01

87: 635-44. 18. Burbelo P, Wellstein A, Pestell RG. Altered Rho GTPase signaling pathways in breast cancer cells. Breast Cancer Res Treat 2004; 84...Burbelo P, Wellstein A, Pestell RG. Altered Rho GTPase signaling pathways in breast cancer cells. Breast Cancer Res Treat 2004;84:43–8. 19. Band V

Termination factor Rho: From the control of pervasive transcription to cell fate determination in Bacillus subtilis

Science.gov (United States)

Nicolas, Pierre; Repoila, Francis; Bardowski, Jacek; Aymerich, Stéphane

2017-01-01

In eukaryotes, RNA species originating from pervasive transcription are regulators of various cellular processes, from the expression of individual genes to the control of cellular development and oncogenesis. In prokaryotes, the function of pervasive transcription and its output on cell physiology is still unknown. Most bacteria possess termination factor Rho, which represses pervasive, mostly antisense, transcription. Here, we investigate the biological significance of Rho-controlled transcription in the Gram-positive model bacterium Bacillus subtilis. Rho inactivation strongly affected gene expression in B. subtilis, as assessed by transcriptome and proteome analysis of a rho–null mutant during exponential growth in rich medium. Subsequent physiological analyses demonstrated that a considerable part of Rho-controlled transcription is connected to balanced regulation of three mutually exclusive differentiation programs: cell motility, biofilm formation, and sporulation. In the absence of Rho, several up-regulated sense and antisense transcripts affect key structural and regulatory elements of these differentiation programs, thereby suppressing motility and biofilm formation and stimulating sporulation. We dissected how Rho is involved in the activity of the cell fate decision-making network, centered on the master regulator Spo0A. We also revealed a novel regulatory mechanism of Spo0A activation through Rho-dependent intragenic transcription termination of the protein kinase kinB gene. Altogether, our findings indicate that distinct Rho-controlled transcripts are functional and constitute a previously unknown built-in module for the control of cell differentiation in B. subtilis. In a broader context, our results highlight the recruitment of the termination factor Rho, for which the conserved biological role is probably to repress pervasive transcription, in highly integrated, bacterium-specific, regulatory networks. PMID:28723971

A preliminary study of the T1rho values of normal knee cartilage using 3 T-MRI

International Nuclear Information System (INIS)

Goto, Hajimu; Iwama, Yuki; Fujii, Masahiko; Aoyama, Nobukazu; Kubo, Seiji; Kuroda, Ryosuke; Ohno, Yoshiharu; Sugimura, Kazuro

2012-01-01

Introduction: To investigate the degree of the effect of aging and weight-bearing on T1rho values in normal cartilage. Materials and methods: Thirty-two asymptomatic patients were examined using 3.0-T magnetic resonance imaging (MRI) to determine knee cartilage T1rho values and T2 values. The femoral and tibial cartilage was divided into weight-bearing (WB-Rs) and less-weight-bearing (LWB-Rs) regions. Single regression analysis was used to assess the relationship between cartilage T1rho values and age and between T2 values and age. Analysis of variance and post hoc-testing were used to evaluate differences in WB-Rs and LWB-Rs cartilage T1rho values and T2 values. Multiple linear regression modeling was performed to predict cartilage T1rho values. Results: Cartilage T1rho values correlated positively with age for all cartilage regions tested (p < 0.001). There were no significant correlations between cartilage T2 values and age. In both the medial femoral and tibial cartilage, T1rho values were significantly higher in WB-Rs than in LWB-Rs (p < 0.05). There were no significant differences in T2 values between WB-Rs and LWB-Rs. Multiple linear regression analysis showed that both age and weight-bearing were significant predictors of increased medial knee cartilage T1rho values (p < 0.001). Conclusions: Aging and the degree of weight-bearing correlate with the change in cartilage T1rho values. Based on multiple regression modeling, aging may be a more important factor than weight-bearing for cartilage T1rho values.

Role of the strange quark in the rho(770) meson

Energy Technology Data Exchange (ETDEWEB)

Molina Peralta, Raquel [George Washington Univ., Washington, DC (United States); Guo, Dehua [George Washington Univ., Washington, DC (United States); Hu, B. [George Washington Univ., Washington, DC (United States); Alexandru, Andrei; Doering, Michael [George Washington Univ., Washington, DC (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

2017-03-01

Recently, the GWU lattice group has evaluated high-precision phase-shift data for $\\pi\\pi$ scattering in the $I = 1$, $J = 1$ channel. Unitary Chiral Perturbation Theory describes these data well around the resonance region and for different pion masses. Moreover, it allows to extrapolate to the physical point and estimate the effect of the missing $K\\bar{K}$ channel in the two-flavor lattice calculation. The absence of the strange quark in the lattice data leads to a lower $\\rho$ mass, and the analysis with U$\\chi$PT shows that the $K \\bar{K}$ channel indeed pushes the $\\pi\\pi$-scattering phase shift upward, having a surprisingly large effect on the $\\rho$-mass. The inelasticity is shown to be compatible with the experimental data. The analysis is then extended to all available two-flavor lattice simulations and similar mass shifts are observed. Chiral extrapolations of $N_f = 2 + 1$ lattice simulations for the $\\rho(770)$ are also reported.

Blocking Modification of Eukaryotic Initiation 5A2 Antagonizes Cervical Carcinoma via Inhibition of RhoA/ROCK Signal Transduction Pathway.

Science.gov (United States)

Liu, Xiaojun; Chen, Dong; Liu, Jiamei; Chu, Zhangtao; Liu, Dongli

2017-10-01

Cervical carcinoma is one of the leading causes of cancer-related death for female worldwide. Eukaryotic initiation factor 5A2 belongs to the eukaryotic initiation factor 5A family and is proposed to be a key factor involved in the development of diverse cancers. In the current study, a series of in vivo and in vitro investigations were performed to characterize the role of eukaryotic initiation factor 5A2 in oncogenesis and metastasis of cervical carcinoma. The expression status of eukaryotic initiation factor 5A2 in 15 cervical carcinoma patients was quantified. Then, the effect of eukaryotic initiation factor 5A2 knockdown on in vivo tumorigenicity ability, cell proliferation, cell cycle distribution, and cell mobility of HeLa cells was measured. To uncover the mechanism driving the function of eukaryotic initiation factor 5A2 in cervical carcinoma, expression of members within RhoA/ROCK pathway was detected, and the results were further verified with an RhoA overexpression modification. The level of eukaryotic initiation factor 5A2 in cervical carcinoma samples was significantly higher than that in paired paratumor tissues ( P cycle arrest ( P ROCK I, and ROCK II were downregulated. The above-mentioned changes in eukaryotic initiation factor 5A2 knockdown cells were alleviated by the overexpression of RhoA. The major findings outlined in the current study confirmed the potential of eukaryotic initiation factor 5A2 as a promising prognosis predictor and therapeutic target for cervical carcinoma treatment. Also, our data inferred that eukaryotic initiation factor 5A2 might function in carcinogenesis of cervical carcinoma through an RhoA/ROCK-dependent manner.

A global phylogeny of leafmining Ectoedemia moths (Lepidoptera: Nepticulidae): host plant family shifts and allopatry as drivers of speciation

NARCIS (Netherlands)

Doorenweerd, C.; van Nieukerken, E.J.; Menken, S.B.J.

2015-01-01

Background Host association patterns in Ectoedemia (Lepidoptera: Nepticulidae) are also encountered in other insect groups with intimate plant relationships, including a high degree of monophagy, a preference for ecologically dominant plant families (e.g. Fagaceae, Rosaceae, Salicaceae, and

Automated NMR fragment based screening identified a novel interface blocker to the LARG/RhoA complex.

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Jia Gao

Full Text Available The small GTPase cycles between the inactive GDP form and the activated GTP form, catalyzed by the upstream guanine exchange factors. The modulation of such process by small molecules has been proven to be a fruitful route for therapeutic intervention to prevent the over-activation of the small GTPase. The fragment based approach emerging in the past decade has demonstrated its paramount potential in the discovery of inhibitors targeting such novel and challenging protein-protein interactions. The details regarding the procedure of NMR fragment screening from scratch have been rarely disclosed comprehensively, thus restricts its wider applications. To achieve a consistent screening applicable to a number of targets, we developed a highly automated protocol to cover every aspect of NMR fragment screening as possible, including the construction of small but diverse libray, determination of the aqueous solubility by NMR, grouping compounds with mutual dispersity to a cocktail, and the automated processing and visualization of the ligand based screening spectra. We exemplified our streamlined screening in RhoA alone and the complex of the small GTPase RhoA and its upstream guanine exchange factor LARG. Two hits were confirmed from the primary screening in cocktail and secondary screening over individual hits for LARG/RhoA complex, while one of them was also identified from the screening for RhoA alone. HSQC titration of the two hits over RhoA and LARG alone, respectively, identified one compound binding to RhoA.GDP at a 0.11 mM affinity, and perturbed the residues at the switch II region of RhoA. This hit blocked the formation of the LARG/RhoA complex, validated by the native gel electrophoresis, and the titration of RhoA to ¹⁵N labeled LARG in the absence and presence the compound, respectively. It therefore provides us a starting point toward a more potent inhibitor to RhoA activation catalyzed by LARG.

Allergic sensitization enhances the contribution of Rho-kinase to airway smooth muscle contraction

NARCIS (Netherlands)

Schaafsma, D.; Gosens, Reinout; Bos, I.S.T.; Meurs, Herman; Zaagsma, Hans; Nelemans, Herman

2004-01-01

1 Repeated allergen challenge has been shown to increase the role of Rho-kinase in airway smooth muscle (ASM) contraction. We considered the possibility that active allergic sensitization by itself, that is, without subsequent allergen exposure, could be sufficient to enhance Rho-kinase-mediated ASM

Upregulated STAT3 and RhoA signaling in colorectal cancer (CRC) regulate the invasion and migration of CRC cells.

Science.gov (United States)

Zhang, G-Y; Yang, W-H; Chen, Z

2016-05-01

We aimed to reveal the expression and activation of signal transducers and activators of transcription 3 (STAT3) and RhoA/Rho-associated coiled-coil forming kinase 1 (ROCK1) signaling in CRC tissues, and to investigate the regulatory role of STAT3 and RhoA signaling in the invasion and migration of colorectal cancer cells. We examined the expression of STAT3, RhoA and ROCK1 in CRC tissues with real-time PCR and Western blotting methods. And then we examined the interaction between STAT3 and RhoA/ROCK1 signaling in CRC HT-29 cells with gain-of-function and loss-of-function strategies. In addition, we determined the regulation by STAT3 and RhoA/ROCK1 on the invasion and migration of CRC HT-29 cells. Our study demonstrated a significant upregulation of RhoA and ROCK1 expression and STAT3-Y705 phosphorylation in 32 CRC specimens, compared to the 17 normal CRC tissues. Further study demonstrated there was a coordination between STAT3 and RhoA/Rock signaling in the HT-29 cells. Moreover, STAT3 knockdown or RhoA knockdown significantly repressed the migration and invasion in HT-29 cells and vice versa. STAT3 and RhoA signaling regulate the invasion and migration of CRC cells, implying the orchestrated and oncogenic roles of STAT3 and RhoA/ROCK1 signaling in CRC.

Lovastatin-induced RhoA modulation and its effect on senescence in prostate cancer cells

International Nuclear Information System (INIS)

Lee, Jeeyun; Lee, Inkyoung; Park, Chaehwa; Kang, Won Ki

2006-01-01

Lovastatin inhibits a 3-hydroxy 3-methylglutaryl coenzyme A reductase and prevents the synthesis of cholesterol precursors, such as farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), responsible for important cell signaling in cell proliferation and migration. Recently, the anti-cancer effect of lovastatin has been suggested in various tumor types. In this study, we showed that a low dose lovastatin induced senescence and G1 cell cycle arrest in human prostate cancer cells. Addition of GGPP or mevalonate, but not FPP, prevented the lovastatin-induced G1 phase cell cycle arrest and cell senescence. We found that constitutively active RhoA (caRhoA) reversed lovastatin-induced senescence in caRhoA-transfected PC-3 cells. Thus, we postulate that modulation of RhoA may be critical in lovastatin-induced senescence in PC-3 cells

Genomic characterization, phylogenetic comparison and differential expression of the cyclic nucleotide-gated channels gene family in pear (Pyrus bretchneideri Rehd.).

Science.gov (United States)

Chen, Jianqing; Yin, Hao; Gu, Jinping; Li, Leiting; Liu, Zhe; Jiang, Xueting; Zhou, Hongsheng; Wei, Shuwei; Zhang, Shaoling; Wu, Juyou

2015-01-01

The cyclic nucleotide-gated channel (CNGC) family is involved in the uptake of various cations, such as Ca(2+), to regulate plant growth and respond to biotic and abiotic stresses. However, there is far less information about this family in woody plants such as pear. Here, we provided a genome-wide identification and analysis of the CNGC gene family in pear. Phylogenetic analysis showed that the 21 pear CNGC genes could be divided into five groups (I, II, III, IVA and IVB). The majority of gene duplications in pear appeared to have been caused by segmental duplication and occurred 32.94-39.14 million years ago. Evolutionary analysis showed that positive selection had driven the evolution of pear CNGCs. Motif analyses showed that Group I CNGCs generally contained 26 motifs, which was the greatest number of motifs in all CNGC groups. Among these, eight motifs were shared by each group, suggesting that these domains play a conservative role in CNGC activity. Tissue-specific expression analysis indicated that functional diversification of the duplicated CNGC genes was a major feature of long-term evolution. Our results also suggested that the P-S6 and PBC & hinge domains had co-evolved during the evolution. These results provide valuable information to increase our understanding of the function, evolution and expression analyses of the CNGC gene family in higher plants. Copyright © 2014 Elsevier Inc. All rights reserved.

Inclusive rho0 production in anti pp interactions at 22.4 GeV/c

International Nuclear Information System (INIS)

Ermilova, D.I.; Filippova, V.V.; Samojlov, V.V.

1978-01-01

Inclusive rho 0 production has been investigated in anti pp reactions at 22.4 GeV/c. The total cross section for rho 0 production is 8.1+-2.0 mb. The average number of rhosup(0') s per event is 0.17+-0.03. The average transverse momentum, as obtained by extrapolation of a simple exponential to the psub(T)sup(2) distribution, is 0.52+-0.12 GeV. The Feynman x and center of mass rapidity distributions show rho 0 to be ''centrally'' produced

NUCLEOTIDES IN INFANT FEEDING

Directory of Open Access Journals (Sweden)

L.G. Mamonova

2007-01-01

Full Text Available The article reviews the application of nucleotides-metabolites, playing a key role in many biological processes, for the infant feeding. The researcher provides the date on the nucleotides in the women's milk according to the lactation stages. She also analyzes the foreign experience in feeding newborns with nucleotides-containing milk formulas. The article gives a comparison of nucleotides in the adapted formulas represented in the domestic market of the given products.Key words: children, feeding, nucleotides.

RhoE interferes with Rb inactivation and regulates the proliferation and survival of the U87 human glioblastoma cell line

International Nuclear Information System (INIS)

Poch, Enric; Minambres, Rebeca; Mocholi, Enric; Ivorra, Carmen; Perez-Arago, Amparo; Guerri, Consuelo; Perez-Roger, Ignacio; Guasch, Rosa M.

2007-01-01

Rho GTPases are important regulators of actin cytoskeleton, but they are also involved in cell proliferation, transformation and oncogenesis. One of this proteins, RhoE, inhibits cell proliferation, however the mechanism that regulates this effect remains poorly understood. Therefore, we undertook the present study to determine the role of RhoE in the regulation of cell proliferation. For this purpose we generated an adenovirus system to overexpress RhoE in U87 glioblastoma cells. Our results show that RhoE disrupts actin cytoskeleton organization and inhibits U87 glioblastoma cell proliferation. Importantly, RhoE expressing cells show a reduction in Rb phosphorylation and in cyclin D1 expression. Furthermore, RhoE inhibits ERK activation following serum stimulation of quiescent cells. Based in these findings, we propose that RhoE inhibits ERK activation, thereby decreasing cyclin D1 expression and leading to a reduction in Rb inactivation, and that this mechanism is involved in the RhoE-induced cell growth inhibition. Moreover, we also demonstrate that RhoE induces apoptosis in U87 cells and also in colon carcinoma and melanoma cells. These results indicate that RhoE plays an important role in the regulation of cell proliferation and survival, and suggest that this protein may be considered as an oncosupressor since it is capable to induce apoptosis in several tumor cell lines

Genomic analysis of codon usage shows influence of mutation pressure, natural selection, and host features on Marburg virus evolution.

Science.gov (United States)

Nasrullah, Izza; Butt, Azeem M; Tahir, Shifa; Idrees, Muhammad; Tong, Yigang

2015-08-26

The Marburg virus (MARV) has a negative-sense single-stranded RNA genome, belongs to the family Filoviridae, and is responsible for several outbreaks of highly fatal hemorrhagic fever. Codon usage patterns of viruses reflect a series of evolutionary changes that enable viruses to shape their survival rates and fitness toward the external environment and, most importantly, their hosts. To understand the evolution of MARV at the codon level, we report a comprehensive analysis of synonymous codon usage patterns in MARV genomes. Multiple codon analysis approaches and statistical methods were performed to determine overall codon usage patterns, biases in codon usage, and influence of various factors, including mutation pressure, natural selection, and its two hosts, Homo sapiens and Rousettus aegyptiacus. Nucleotide composition and relative synonymous codon usage (RSCU) analysis revealed that MARV shows mutation bias and prefers U- and A-ended codons to code amino acids. Effective number of codons analysis indicated that overall codon usage among MARV genomes is slightly biased. The Parity Rule 2 plot analysis showed that GC and AU nucleotides were not used proportionally which accounts for the presence of natural selection. Codon usage patterns of MARV were also found to be influenced by its hosts. This indicates that MARV have evolved codon usage patterns that are specific to both of its hosts. Moreover, selection pressure from R. aegyptiacus on the MARV RSCU patterns was found to be dominant compared with that from H. sapiens. Overall, mutation pressure was found to be the most important and dominant force that shapes codon usage patterns in MARV. To our knowledge, this is the first detailed codon usage analysis of MARV and extends our understanding of the mechanisms that contribute to codon usage and evolution of MARV.

Nucleotide Metabolism

DEFF Research Database (Denmark)

Martinussen, Jan; Willemoës, M.; Kilstrup, Mogens

2011-01-01

Metabolic pathways are connected through their utilization of nucleotides as supplier of energy, allosteric effectors, and their role in activation of intermediates. Therefore, any attempt to exploit a given living organism in a biotechnological process will have an impact on nucleotide metabolis...

Foci of cyclin A2 interact with actin and RhoA in mitosis.

Science.gov (United States)

Loukil, Abdelhalim; Izard, Fanny; Georgieva, Mariya; Mashayekhan, Shaereh; Blanchard, Jean-Marie; Parmeggiani, Andrea; Peter, Marion

2016-06-09

Cyclin A2 is a key player in the regulation of the cell cycle. Its degradation in mid-mitosis depends primarily on the ubiquitin-proteasome system (UPS), while autophagy also contributes. However, a fraction of cyclin A2 persists beyond metaphase. In this work, we focus on cyclin A2-rich foci detected in mitosis by high resolution imaging and analyse their movements. We demonstrate that cyclin A2 interacts with actin and RhoA during mitosis, and that cyclin A2 depletion induces a dramatic decrease in active RhoA in mitosis. Our data suggest cyclin A2 participation in RhoA activation in late mitosis.

Molecular insight into systematics, host associations, life cycles and geographic distribution of the nematode family Rhabdiasidae.

Science.gov (United States)

Tkach, Vasyl V; Kuzmin, Yuriy; Snyder, Scott D

2014-04-01

Rhabdiasidae Railliet, 1915 is a globally distributed group of up to 100 known species of nematodes parasitic in amphibians and reptiles. This work presents the results of a molecular phylogenetic analysis of 36 species of Rhabdiasidae from reptiles and amphibians from six continents. New DNA sequences encompassing partial 18S rDNA, ITS1, 5.8S rDNA, ITS2 and partial 28S rDNA regions of nuclear ribosomal DNA were obtained from 27 species and pre-existing sequences for nine species were incorporated. The broad taxonomic, host and geographical coverage of the specimens allowed us to address long-standing questions in rhabdiasid systematics, evolution, geographic distribution, and patterns of host association. Our analysis demonstrated that rhabdiasids parasitic in snakes are an independent genus sister to the rest of the Rhabdiasidae, a status supported by life cycle data. Based on the combined evidence of molecular phylogeny, morphology and life cycle characteristics, a new genus Serpentirhabdias gen. nov. with the type species Serpentirhabdias elaphe (Sharpilo, 1976) comb. nov. is established. The phylogeny supports the monophyly of Entomelas Travassos, 1930, Pneumonema Johnston, 1916 and the largest genus of the family, Rhabdias Stiles and Hassall, 1905. DNA sequence comparisons demonstrate the presence of more than one species in the previously monotypic Pneumonema from Australian scincid lizards. The distribution of some morphological characters in the genus Rhabdias shows little consistency within the phylogenetic tree topology, in particular the apical structures widely used in rhabdiasid systematics. Our data suggest that some of the characters, while valuable for species differentiation, are not appropriate for differentiation among higher taxa and are of limited phylogenetic utility. Rhabdias is the only genus with a cosmopolitan distribution, but some of the lineages within Rhabdias are distributed on a single continent or a group of adjacent

PTP-PEST targets a novel tyrosine site in p120 catenin to control epithelial cell motility and Rho GTPase activity

Science.gov (United States)

Espejo, Rosario; Jeng, Yowjiun; Paulucci-Holthauzen, Adriana; Rengifo-Cam, William; Honkus, Krysta; Anastasiadis, Panos Z.; Sastry, Sarita K.

2014-01-01

ABSTRACT Tyrosine phosphorylation is implicated in regulating the adherens junction protein, p120 catenin (p120), however, the mechanisms are not well defined. Here, we show, using substrate trapping, that p120 is a direct target of the protein tyrosine phosphatase, PTP-PEST, in epithelial cells. Stable shRNA knockdown of PTP-PEST in colon carcinoma cells results in an increased cytosolic pool of p120 concomitant with its enhanced tyrosine phosphorylation and decreased association with E-cadherin. Consistent with this, PTP-PEST knockdown cells exhibit increased motility, enhanced Rac1 and decreased RhoA activity on a collagen substrate. Furthermore, p120 localization is enhanced at actin-rich protrusions and lamellipodia and has an increased association with the guanine nucleotide exchange factor, VAV2, and cortactin. Exchange factor activity of VAV2 is enhanced by PTP-PEST knockdown whereas overexpression of a VAV2 C-terminal domain or DH domain mutant blocks cell motility. Analysis of point mutations identified tyrosine 335 in the N-terminal domain of p120 as the site of PTP-PEST dephosphorylation. A Y335F mutant of p120 failed to induce the ‘p120 phenotype’, interact with VAV2, stimulate cell motility or activate Rac1. Together, these data suggest that PTP-PEST affects epithelial cell motility by controlling the distribution and phosphorylation of p120 and its availability to control Rho GTPase activity. PMID:24284071

Rho0 Photoproduction in Ultra-Peripheral Relativistic Heavy Ion Collisions with STAR

Energy Technology Data Exchange (ETDEWEB)

STAR Coll

2007-12-20

Photoproduction reactions occur when the electromagnetic field of a relativistic heavy ion interacts with another heavy ion. The STAR collaboration presents a measurement of {rho}{sup 0} and direct {pi}{sup +}{pi}{sup -} photoproduction in ultra-peripheral relativistic heavy ion collisions at {radical}s{sub NN} = 200 GeV. We observe both exclusive photoproduction and photoproduction accompanied by mutual Coulomb excitation. We find a coherent cross-section of {sigma}(AuAu {yields} Au*Au* {rho}{sup 0}) = 530 {+-} 19 (stat.) {+-} 57 (syst.) mb, in accord with theoretical calculations based on a Glauber approach, but considerably below the predictions of a color dipole model. The {rho}{sup 0} transverse momentum spectrum (p{sub T}{sup 2}) is fit by a double exponential curve including both coherent and incoherent coupling to the target nucleus; we find {sigma}{sub inc}/{sigma}{sub coh} = 0.29 {+-} 0.03 (stat.) {+-} 0.08 (syst.). The ratio of direct {pi}{sup +}{pi}{sup -} production is comparable to that observed in {gamma}p collisions at HERA, and appears to be independent of photon energy. Finally, the measured {rho}{sup 0} spin helicity matrix elements agree within errors with the expected s-channel helicity conservation.

Computational learning on specificity-determining residue-nucleotide interactions

KAUST Repository

Wong, Ka-Chun; Li, Yue; Peng, Chengbin; Moses, Alan M.; Zhang, Zhaolei

2015-01-01

The protein–DNA interactions between transcription factors and transcription factor binding sites are essential activities in gene regulation. To decipher the binding codes, it is a long-standing challenge to understand the binding mechanism across different transcription factor DNA binding families. Past computational learning studies usually focus on learning and predicting the DNA binding residues on protein side. Taking into account both sides (protein and DNA), we propose and describe a computational study for learning the specificity-determining residue-nucleotide interactions of different known DNA-binding domain families. The proposed learning models are compared to state-of-the-art models comprehensively, demonstrating its competitive learning performance. In addition, we describe and propose two applications which demonstrate how the learnt models can provide meaningful insights into protein–DNA interactions across different DNA binding families.

Computational learning on specificity-determining residue-nucleotide interactions

KAUST Repository

Wong, Ka-Chun

2015-11-02

The protein–DNA interactions between transcription factors and transcription factor binding sites are essential activities in gene regulation. To decipher the binding codes, it is a long-standing challenge to understand the binding mechanism across different transcription factor DNA binding families. Past computational learning studies usually focus on learning and predicting the DNA binding residues on protein side. Taking into account both sides (protein and DNA), we propose and describe a computational study for learning the specificity-determining residue-nucleotide interactions of different known DNA-binding domain families. The proposed learning models are compared to state-of-the-art models comprehensively, demonstrating its competitive learning performance. In addition, we describe and propose two applications which demonstrate how the learnt models can provide meaningful insights into protein–DNA interactions across different DNA binding families.

Exclusive {rho}{sup 0} production in deep inelastic scattering at HERA

Energy Technology Data Exchange (ETDEWEB)

Chekanov, S.; Derrick, M.; Magill, S. [Argonne National Laboratory, Argonne, IL (US)] (and others)

2007-08-15

Exclusive {rho}{sup 0} electroproduction at HERA has been studied with the ZEUS detector using 120 pb{sup -1} of integrated luminosity collected during 1996-2000. The analysis was carried out in the kinematic range of photon virtuality 2rho}{sup 0}p cross section and the distribution of the squared-four-momentum transfer to the proton. The helicity analysis of the decay-matrix elements of the {rho}{sup 0} was used to study the ratio of the {gamma}{sup *}p cross section for longitudinal and transverse photon as a function of Q{sup 2} and W. Finally, an effective Pomeron trajectory was extracted. The results are compared to various theoretical predictions. (orig.)

The Emerging Role of Guanine Exchange Factors in ALS and other neurodegenerative diseases

Directory of Open Access Journals (Sweden)

Cristian eDroppelmann

2014-09-01

Full Text Available Small GTPases participate in a broad range of cellular processes such as proliferation, differentiation and migration. The exchange of GDP for GTP resulting in the activation of these GTPases is catalyzed by a group of enzymes called guanine nucleotide exchange factors (GEFs, of which two classes: Dbl-related exchange factors and the more recently described Dock family exchange factors. Increasingly, deregulation of normal GEF activity or function has been associated with a broad range of disease states, including neurodegeneration and neurodevelopmental disorders. In this review, we examine this evidence with special emphasis on the novel role of Rho guanine nucleotide exchange factor (RGNEF/p190RhoGEF in the pathogenesis of amyotrophic lateral sclerosis (ALS. RGNEF is the first neurodegeneration-linked GEF that regulates not only RhoA GTPase activation but also functions as an RNA binding protein that directly acts with low molecular weight neurofilament (NEFL mRNA 3’UTR to regulate its stability. This dual role for RGNEF, coupled with the increasing understanding of the key role for GEFs in modulating the GTPase function in cell survival suggests a prominent role for GEFs in mediating a critical balance between cytotoxicity and neuroprotection which, when disturbed, contributes to neuronal loss.

Crystallization and preliminary X-ray crystallographic characterization of a cyclic nucleotide-binding homology domain from the mouse EAG potassium channel

International Nuclear Information System (INIS)

Marques-Carvalho, Maria João; Morais-Cabral, João Henrique

2012-01-01

The crystallization conditions and preliminary crystal characterization of the cytoplasmic cyclic nucleotide-binding homology domain from the mouse EAG potassium channel are reported. The members of the family of voltage-gated KCNH potassium channels play important roles in cardiac and neuronal repolarization, tumour proliferation and hormone secretion. These channels have a C-terminal cytoplasmic domain which is homologous to cyclic nucleotide-binding domains (CNB-homology domains), but it has been demonstrated that channel function is not affected by cyclic nucleotides and that the domain does not bind nucleotides in vitro. Here, the crystallization and preliminary crystallographic analysis of a CNB-homology domain from a member of the KCNH family, the mouse EAG channel, is reported. X-ray diffraction data were collected to 2.2 Å resolution and the crystal belonged to the hexagonal space group P3 1 21

Expression and cytoprotective activity of the small GTPase RhoB induced by the Escherichia coli cytotoxic necrotizing factor 1

DEFF Research Database (Denmark)

Huelsenbeck, Stefanie C; Roggenkamp, Dennis; May, Martin

2013-01-01

B expression, based on the inactivation of Rho/Ras proteins. In this study, we report on a long lasting expression of RhoB in cultured cells upon activation of Rho proteins by the cytotoxic necrotizing factor 1 (CNF1) from Escherichia coli. The observations of this study highlight a new pathway involving Rac1...... without any signs of cell death. In conclusion, the cytoprotective RhoB response is not only evoked by bacterial protein toxins inactivating Rho/Ras proteins but also by the Rac1-activating toxin CNF1....

The Phosphatidylinositol (3,4,5)-Trisphosphate-dependent Rac Exchanger 1·Ras-related C3 Botulinum Toxin Substrate 1 (P-Rex1·Rac1) Complex Reveals the Basis of Rac1 Activation in Breast Cancer Cells.

Science.gov (United States)

Lucato, Christina M; Halls, Michelle L; Ooms, Lisa M; Liu, Heng-Jia; Mitchell, Christina A; Whisstock, James C; Ellisdon, Andrew M

2015-08-21

The P-Rex (phosphatidylinositol (3,4,5)-trisphosphate (PIP3)-dependent Rac exchanger) family (P-Rex1 and P-Rex2) of the Rho guanine nucleotide exchange factors (Rho GEFs) activate Rac GTPases to regulate cell migration, invasion, and metastasis in several human cancers. The family is unique among Rho GEFs, as their activity is regulated by the synergistic binding of PIP3 and Gβγ at the plasma membrane. However, the molecular mechanism of this family of multi-domain proteins remains unclear. We report the 1.95 Å crystal structure of the catalytic P-Rex1 DH-PH tandem domain in complex with its cognate GTPase, Rac1 (Ras-related C3 botulinum toxin substrate-1). Mutations in the P-Rex1·Rac1 interface revealed a critical role for this complex in signaling downstream of receptor tyrosine kinases and G protein-coupled receptors. The structural data indicated that the PIP3/Gβγ binding sites are on the opposite surface and markedly removed from the Rac1 interface, supporting a model whereby P-Rex1 binding to PIP3 and/or Gβγ releases inhibitory C-terminal domains to expose the Rac1 binding site. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

On $rho$-dilations of commuting operators

Czech Academy of Sciences Publication Activity Database

Müller, Vladimír

2017-01-01

Roč. 78, č. 1 (2017), s. 3-20 ISSN 0379-4024 R&D Projects: GA ČR(CZ) GA14-07880S Institutional support: RVO:67985840 Keywords : regular unitary dilation * rho-dilation Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 0.524, year: 2016 http://www.mathjournals.org/jot/2017-078-001/2017-078-001-001. html

Downstream components of RhoA required for signal pathway of superoxide formation during phagocytosis of serum opsonized zymosans in macrophages.

Science.gov (United States)

Kim, Jun Sub; Kim, Jae Gyu; Jeon, Chan Young; Won, Ha Young; Moon, Mi Young; Seo, Ji Yeon; Kim, Jong Il; Kim, Jaebong; Lee, Jae Yong; Choi, Soo Young; Park, Jinseu; Yoon Park, Jung Han; Ha, Kwon Soo; Kim, Pyeung Hyeun; Park, Jae Bong

2005-12-31

Rac1 and Rac2 are essential for the control of oxidative burst catalyzed by NADPH oxidase. It was also documented that Rho is associated with the superoxide burst reaction during phagocytosis of serum- (SOZ) and IgG-opsonized zymosan particles (IOZ). In this study, we attempted to reveal the signal pathway components in the superoxide formation regulated by Rho GTPase. Tat-C3 blocked superoxide production, suggesting that RhoA is essentially involved in superoxide formation during phagocytosis of SOZ. Conversely SOZ activated both RhoA and Rac1/2. Inhibition of RhoA-activated kinase (ROCK), an important downstream effector of RhoA, by Y27632 and myosin light chain kinase (MLCK) by ML-7 abrogated superoxide production by SOZ. Extracellular signaling-regulated kinase (ERK)1/2 and p38 mitogen-activated protein kinase (MAPK) were activated during phagocytosis of SOZ, and Tat-C3 and SB203580 reduced ERK1/2 and p38 MAPK activation, suggesting that RhoA and p38 MAPK may be upstream regulators of ERK1/2. Inhibition of ERK1/2, p38 MAPK, phosphatidyl inositol 3-kinase did not block translocation of RhoA to membranes, suggesting that RhoA is upstream to these kinases. Inhibition of RhoA by Tat-C3 blocked phosphorylation of p47(PHOX). Taken together, RhoA, ROCK, p38MAPK, ERK1/2, and p47(PHOX) may be subsequently activated, leading to activation of NADPH oxidase to produce superoxide.

Infralimbic cortex Rho-kinase inhibition causes antidepressant-like activity in rats.

Science.gov (United States)

Inan, Salim Yalcin; Soner, Burak Cem; Sahin, Ayse Saide

2015-03-03

Depression is one of the most common psychiatric disorders in the world; however, its mechanisms remain unclear. Recently, a new signal-transduction pathway, namely Rho/Rho-kinase signalling, has been suggested to be involved in diverse cellular events in the central nervous system; such as epilepsy, anxiety-related behaviors, regulation of dendritic and axonal morphology, antinociception, subarachnoid haemorrhage, spinal cord injury and amyotrophic lateral sclerosis. However there is no evidence showing the involvement of Rho-kinase pathway in depression. In addition, the infralimbic cortex, rodent equivalent to subgenual cingulate cortex has been shown to be responsible for emotional responses. Thus, in the present study, intracranial guide cannulae were stereotaxically implanted bilaterally into the infralimbic cortex, and the effects of repeated microinjections of a Rho-kinase (ROCK) inhibitor Y-27632 (10 nmol) were investigated in rats. Y-27632 significantly decreased immobility time and increased swimming and climbing behaviors when compared to fluoxetine (10 μg) and saline groups in the forced swim test. In addition, Y-27632 treatment did not affect spontaneous locomotor activity and forelimb use in the open-field and cylinder tests respectively; but it enhanced limb placing accuracy in the ladder rung walking test. Our results suggest that Y-27632 could be a potentially active antidepressant agent. Copyright © 2014 Elsevier Inc. All rights reserved.

A proteomic approach for comprehensively screening substrates of protein kinases such as Rho-kinase.

Directory of Open Access Journals (Sweden)

Mutsuki Amano

Full Text Available BACKGROUND: Protein kinases are major components of signal transduction pathways in multiple cellular processes. Kinases directly interact with and phosphorylate downstream substrates, thus modulating their functions. Despite the importance of identifying substrates in order to more fully understand the signaling network of respective kinases, efficient methods to search for substrates remain poorly explored. METHODOLOGY/PRINCIPAL FINDINGS: We combined mass spectrometry and affinity column chromatography of the catalytic domain of protein kinases to screen potential substrates. Using the active catalytic fragment of Rho-kinase/ROCK/ROK as the model bait, we obtained about 300 interacting proteins from the rat brain cytosol fraction, which included the proteins previously reported as Rho-kinase substrates. Several novel interacting proteins, including doublecortin, were phosphorylated by Rho-kinase both in vitro and in vivo. CONCLUSIONS/SIGNIFICANCE: This method would enable identification of novel specific substrates for kinases such as Rho-kinase with high sensitivity.

An ELMO2-RhoG-ILK network modulates microtubule dynamics.

Science.gov (United States)

Jackson, Bradley C; Ivanova, Iordanka A; Dagnino, Lina

2015-07-15

ELMO2 belongs to a family of scaffold proteins involved in phagocytosis and cell motility. ELMO2 can simultaneously bind integrin-linked kinase (ILK) and RhoG, forming tripartite ERI complexes. These complexes are involved in promoting β1 integrin-dependent directional migration in undifferentiated epidermal keratinocytes. ELMO2 and ILK have also separately been implicated in microtubule regulation at integrin-containing focal adhesions. During differentiation, epidermal keratinocytes cease to express integrins, but ERI complexes persist. Here we show an integrin-independent role of ERI complexes in modulation of microtubule dynamics in differentiated keratinocytes. Depletion of ERI complexes by inactivating the Ilk gene in these cells reduces microtubule growth and increases the frequency of catastrophe. Reciprocally, exogenous expression of ELMO2 or RhoG stabilizes microtubules, but only if ILK is also present. Mechanistically, activation of Rac1 downstream from ERI complexes mediates their effects on microtubule stability. In this pathway, Rac1 serves as a hub to modulate microtubule dynamics through two different routes: 1) phosphorylation and inactivation of the microtubule-destabilizing protein stathmin and 2) phosphorylation and inactivation of GSK-3β, which leads to the activation of CRMP2, promoting microtubule growth. At the cellular level, the absence of ERI species impairs Ca(2+)-mediated formation of adherens junctions, critical to maintaining mechanical integrity in the epidermis. Our findings support a key role for ERI species in integrin-independent stabilization of the microtubule network in differentiated keratinocytes. © 2015 Jackson et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

A global phylogeny of leafmining Ectoedemia moths (Lepidoptera: Nepticulidae): exploring host plant family shifts and allopatry as drivers of speciation

NARCIS (Netherlands)

Doorenweerd, C.; Nieukerken, van E.J.; Menken, S.B.J.

2015-01-01

Background: Host association patterns in Ectoedemia (Lepidoptera: Nepticulidae) are also encountered in other insect groups with intimate plant relationships, including a high degree of monophagy, a preference for ecologically dominant plant families (e.g. Fagaceae, Rosaceae, Salicaceae, and

Estrogen's Place in the Family of Synaptic Modulators.

Science.gov (United States)

Kramár, Enikö A; Chen, Lulu Y; Rex, Christopher S; Gall, Christine M; Lynch, Gary

2009-01-01

Estrogen, in addition to its genomic effects, triggers rapid synaptic changes in hippocampus and cortex. Here we summarize evidence that the acute actions of the steroid arise from actin signaling cascades centrally involved in long-term potentiation (LTP). A 10-min infusion of E2 reversibly increased fast EPSPs and promoted theta burst-induced LTP within adult hippocampal slices. The latter effect reflected a lowered threshold and an elevated ceiling for the potentiation effect. E2's actions on transmission and plasticity were completely blocked by latrunculin, a toxin that prevents actin polymerization. E2 also caused a reversible increase in spine concentrations of filamentous (F-) actin and markedly enhanced polymerization caused by theta burst stimulation (TBS). Estrogen activated the small GTPase RhoA, but not the related GTPase Rac, and phosphorylated (inactivated) synaptic cofilin, an actin severing protein targeted by RhoA. An inhibitor of RhoA kinase (ROCK) thoroughly suppressed the synaptic effects of E2. Collectively, these results indicate that E2 engages a RhoA >ROCK> cofilin> actin pathway also used by brain-derived neurotrophic factor and adenosine, and therefore belongs to a family of 'synaptic modulators' that regulate plasticity. Finally, we describe evidence that the acute signaling cascade is critical to the depression of LTP produced by ovariectomy.

T1rho MRI of menisci and cartilage in patients with osteoarthritis at 3T

Energy Technology Data Exchange (ETDEWEB)

Wang, Ligong, E-mail: ligong.wang@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY (United States); Chang, Gregory, E-mail: gregory.chang@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY (United States); Xu, Jian, E-mail: jian.xu.sz@siemens.com [Siemens HealthCare, New York, NY (United States); Vieira, Renata L.R., E-mail: Renata.Vieira@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY (United States); Krasnokutsky, Svetlana, E-mail: Svetlana.Krasnokutsky@nyumc.org [Division of Rheumatology, New York University Langone Medical Center, New York, NY (United States); Abramson, Steven, E-mail: StevenB.Abramson@nyumc.org [Division of Rheumatology, New York University Langone Medical Center, New York, NY (United States); Regatte, Ravinder R., E-mail: Ravinder.Regatte@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY (United States)

2012-09-15

Objective: To assess and compare subregional and whole T1rho values (median ± interquartile range) of femorotibial cartilage and menisci in patients with doubtful (Kellgren–Lawrence (KL) grade 1) to severe (KL4) osteoarthritis (OA) at 3T. Materials and methods: 30 subjects with varying degrees of OA (KL1–4, 13 females, 17 males, mean age ± SD = 63.9 ± 13.1 years) were evaluated on a 3T MR scanner using a spin-lock-based 3D GRE sequence for T1rho mapping. Clinical proton density (PD)-weighted fast spin echo (FSE) images in sagittal (without fat saturation), axial, and coronal (fat-saturated) planes were acquired for cartilage and meniscus Whole-organ MR imaging score (WORMS) grading. Wilcoxon rank sum test was performed to determine whether there were any statistically significant differences between subregional and whole T1rho values of femorotibial cartilage and menisci in subjects with doubtful to severe OA. Results: Lateral (72 ± 10 ms, median ± interquartile range) and medial (65 ± 10 ms) femoral anterior cartilage subregions in moderate–severe OA subjects had significantly higher T1rho values (P < 0.05) than cartilage subregions and whole femorotibial cartilage in doubtful–minimal OA subjects. There were statistically significant differences in meniscus T1rho values of the medial posterior subregion of subjects with moderate–severe OA and T1rho values of all subregions and the whole meniscus in subjects with doubtful–minimal OA. When evaluated based on WORMS, statistically significant differences were identified in T1rho values between the lateral femoral anterior cartilage subregion in patients with WORMS5–6 (advanced degeneration) and whole femorotibial cartilage and all cartilage subregions in patients with WORMS0–1 (normal). Conclusion: T1rho values are higher in specific meniscus and femorotibial cartilage subregions. These findings suggest that regional damage of both femorotibial hyaline cartilage and menisci may be associated with

Diabetes and overexpression of proNGF cause retinal neurodegeneration via activation of RhoA pathway.

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Mohammed M H Al-Gayyar

Full Text Available Our previous studies showed positive correlation between accumulation of proNGF, activation of RhoA and neuronal death in diabetic models. Here, we examined the neuroprotective effects of selective inhibition of RhoA kinase in the diabetic rat retina and in a model that stably overexpressed the cleavage-resistance proNGF plasmid in the retina. Male Sprague-Dawley rats were rendered diabetic using streptozotocin or stably express cleavage-resistant proNGF plasmid. The neuroprotective effects of the intravitreal injection of RhoA kinase inhibitor Y27632 were examined in vivo. Effects of proNGF were examined in freshly isolated primary retinal ganglion cell (RGC cultures and RGC-5 cell line. Retinal neurodegeneration was assessed by counting TUNEL-positive and Brn-3a positive retinal ganglion cells. Expression of proNGF, p75(NTR, cleaved-PARP, caspase-3 and p38MAPK/JNK were examined by Western-blot. Activation of RhoA was assessed by pull-down assay and G-LISA. Diabetes and overexpression of proNGF resulted in retinal neurodegeneration as indicated by 9- and 6-fold increase in TUNEL-positive cells, respectively. In vitro, proNGF induced 5-fold cell death in RGC-5 cell line, and it induced >10-fold cell death in primary RGC cultures. These effects were associated with significant upregulation of p75(NTR and activation of RhoA. While proNGF induced TNF-α expression in vivo, it selectively activated RhoA in primary RGC cultures and RGC-5 cell line. Inhibiting RhoA kinase with Y27632 significantly reduced diabetes- and proNGF-induced activation of proapoptotic p38MAPK/JNK, expression of cleaved-PARP and caspase-3 and prevented retinal neurodegeneration in vivo and in vitro. Taken together, these results provide compelling evidence for a causal role of proNGF in diabetes-induced retinal neurodegeneration through enhancing p75(NTR expression and direct activation of RhoA and p38MAPK/JNK apoptotic pathways.

T1rho MRI of menisci and cartilage in patients with osteoarthritis at 3T

International Nuclear Information System (INIS)

Wang, Ligong; Chang, Gregory; Xu, Jian; Vieira, Renata L.R.; Krasnokutsky, Svetlana; Abramson, Steven; Regatte, Ravinder R.

2012-01-01

Objective: To assess and compare subregional and whole T1rho values (median ± interquartile range) of femorotibial cartilage and menisci in patients with doubtful (Kellgren–Lawrence (KL) grade 1) to severe (KL4) osteoarthritis (OA) at 3T. Materials and methods: 30 subjects with varying degrees of OA (KL1–4, 13 females, 17 males, mean age ± SD = 63.9 ± 13.1 years) were evaluated on a 3T MR scanner using a spin-lock-based 3D GRE sequence for T1rho mapping. Clinical proton density (PD)-weighted fast spin echo (FSE) images in sagittal (without fat saturation), axial, and coronal (fat-saturated) planes were acquired for cartilage and meniscus Whole-organ MR imaging score (WORMS) grading. Wilcoxon rank sum test was performed to determine whether there were any statistically significant differences between subregional and whole T1rho values of femorotibial cartilage and menisci in subjects with doubtful to severe OA. Results: Lateral (72 ± 10 ms, median ± interquartile range) and medial (65 ± 10 ms) femoral anterior cartilage subregions in moderate–severe OA subjects had significantly higher T1rho values (P < 0.05) than cartilage subregions and whole femorotibial cartilage in doubtful–minimal OA subjects. There were statistically significant differences in meniscus T1rho values of the medial posterior subregion of subjects with moderate–severe OA and T1rho values of all subregions and the whole meniscus in subjects with doubtful–minimal OA. When evaluated based on WORMS, statistically significant differences were identified in T1rho values between the lateral femoral anterior cartilage subregion in patients with WORMS5–6 (advanced degeneration) and whole femorotibial cartilage and all cartilage subregions in patients with WORMS0–1 (normal). Conclusion: T1rho values are higher in specific meniscus and femorotibial cartilage subregions. These findings suggest that regional damage of both femorotibial hyaline cartilage and menisci may be associated with

Analysis of odorant-binding protein gene family members in the polyembryonic wasp, Copidosoma floridanum: evidence for caste bias and host interaction.

Science.gov (United States)

Donnell, David M

2014-01-01

The polyembryonic wasp Copidosoma floridanum produces two larval castes, soldiers and reproductives, during development within its caterpillar host. Primary structures were determined for 6 odorant-binding protein (OBP) gene family members in Copidosoma and then analyzed alongside two formerly sequenced OBP genes from this wasp. The genes were examined for caste-bias in expression patterns using reverse transcription-polymerase chain reaction (RT-PCR) and in situ expression studies. Six of the 8 genes show a clear bias in gene expression towards one or the other larval caste. Of the 3 distinct in situ probe hybridization patterns observed in this study, none lie in tissues with clear chemosensory functions. Two of the patterns suggest the majority of the Copidosoma OBP gene family members discovered thus far come into contact with host hemolymph. Most of these OBPs are expressed exclusively in the serosal membrane encompassing each of the reproductive larvae. The absence of expression in the membrane surrounding soldier larvae strongly suggests these OBPs are performing caste-specific functions in the host. Copyright © 2013 Elsevier Ltd. All rights reserved.

Host Phylogeny Determines Viral Persistence and Replication in Novel Hosts

Science.gov (United States)

Longdon, Ben; Hadfield, Jarrod D.; Webster, Claire L.

2011-01-01

Pathogens switching to new hosts can result in the emergence of new infectious diseases, and determining which species are likely to be sources of such host shifts is essential to understanding disease threats to both humans and wildlife. However, the factors that determine whether a pathogen can infect a novel host are poorly understood. We have examined the ability of three host-specific RNA-viruses (Drosophila sigma viruses from the family Rhabdoviridae) to persist and replicate in 51 different species of Drosophilidae. Using a novel analytical approach we found that the host phylogeny could explain most of the variation in viral replication and persistence between different host species. This effect is partly driven by viruses reaching a higher titre in those novel hosts most closely related to the original host. However, there is also a strong effect of host phylogeny that is independent of the distance from the original host, with viral titres being similar in groups of related hosts. Most of this effect could be explained by variation in general susceptibility to all three sigma viruses, as there is a strong phylogenetic correlation in the titres of the three viruses. These results suggest that the source of new emerging diseases may often be predictable from the host phylogeny, but that the effect may be more complex than simply causing most host shifts to occur between closely related hosts. PMID:21966271

Lysophosphatidic acid-induced RhoA signaling and prolonged macrophage infiltration worsens fibrosis and fatty infiltration following rotator cuff tears.

Science.gov (United States)

Davies, Michael R; Lee, Lawrence; Feeley, Brian T; Kim, Hubert T; Liu, Xuhui

2017-07-01

Previous studies have suggested that macrophage-mediated chronic inflammation is involved in the development of rotator cuff muscle atrophy and degeneration following massive tendon tears. Increased RhoA signaling has been reported in chronic muscle degeneration, such as muscular dystrophy. However, the role of RhoA signaling in macrophage infiltration and rotator muscle degeneration remains unknown. Using a previously established rat model of massive rotator cuff tears, we found RhoA signaling is upregulated in rotator cuff muscle following a massive tendon-nerve injury. This increase in RhoA expression is greatly potentiated by the administration of a potent RhoA activator, lysophosphatidic acid (LPA), and is accompanied by increased TNFα and TGF-β1 expression in rotator cuff muscle. Boosting RhoA signaling with LPA significantly worsened rotator cuff muscle atrophy, fibrosis, and fatty infiltration, accompanied with massive monocytic infiltration of rotator cuff muscles. Co-staining of RhoA and the tissue macrophage marker CD68 showed that CD68+ tissue macrophages are the dominant cell source of increased RhoA signaling in rotator cuff muscles after tendon tears. Taken together, our findings suggest that LPA-mediated RhoA signaling in injured muscle worsens the outcomes of atrophy, fibrosis, and fatty infiltration by increasing macrophage infiltraion in rotator cuff muscle. Clinically, inhibiting RhoA signaling may represent a future direction for developing new treatments to improve muscle quality following massive rotator cuff tears. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1539-1547, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Rho-Kinase/ROCK as a Potential Drug Target for Vitreoretinal Diseases

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Muneo Yamaguchi

2017-01-01

Full Text Available Rho-associated kinase (Rho-kinase/ROCK was originally identified as an effector protein of the G protein Rho. Its involvement in various diseases, particularly cancer and cardiovascular disease, has been elucidated, and ROCK inhibitors have already been applied clinically for cerebral vasospasm and glaucoma. Vitreoretinal diseases including diabetic retinopathy, age-related macular degeneration, and proliferative vitreoretinoapthy are still a major cause of blindness. While anti-VEGF therapy has recently been widely used for vitreoretinal disorders due to its efficacy, attention has been drawn to new unmet needs. The importance of ROCK in pathological vitreoretinal conditions has also been elucidated and is attracting attention as a potential therapeutic target. ROCK is involved in angiogenesis and hyperpermeability and also in the pathogenesis of various pathologies such as inflammation and fibrosis. It has been expected that ROCK inhibitors will become new molecular target drugs for vitreoretinal diseases. This review summarizes the recent progress on the mechanisms of action of ROCK and their applications in disease treatment.

Global Transcriptional Regulation of Backbone Genes in Broad-Host-Range Plasmid RA3 from the IncU Group Involves Segregation Protein KorB (ParB Family).

Science.gov (United States)

Kulinska, Anna; Godziszewska, Jolanta; Wojciechowska, Anna; Ludwiczak, Marta; Jagura-Burdzy, Grazyna

2016-04-01

The KorB protein of the broad-host-range conjugative plasmid RA3 from the IncU group belongs to the ParB family of plasmid and chromosomal segregation proteins. As a partitioning DNA-binding factor, KorB specifically recognizes a 16-bp palindrome which is an essential motif in the centromere-like sequence parSRA3, forms a segrosome, and together with its partner IncC (ParA family) participates in active DNA segregation ensuring stable plasmid maintenance. Here we show that by binding to this palindromic sequence, KorB also acts as a repressor for the adjacent mobC promoter driving expression of the mobC-nicoperon, which is involved in DNA processing during conjugation. Three other promoters, one buried in the conjugative transfer module and two divergent promoters located at the border between the replication and stability regions, are regulated by KorB binding to additional KorB operators (OBs). KorB acts as a repressor at a distance, binding to OBs separated from their cognate promoters by between 46 and 1,317 nucleotides. This repressor activity is facilitated by KorB spreading along DNA, since a polymerization-deficient KorB variant with its dimerization and DNA-binding abilities intact is inactive in transcriptional repression. KorB may act as a global regulator of RA3 plasmid functions in Escherichia coli, since its overexpression in transnegatively interferes with mini-RA3 replication and stable maintenance of RA3. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Novel IgG-Degrading Enzymes of the IgdE Protease Family Link Substrate Specificity to Host Tropism of Streptococcus Species.

Science.gov (United States)

Spoerry, Christian; Hessle, Pontus; Lewis, Melanie J; Paton, Lois; Woof, Jenny M; von Pawel-Rammingen, Ulrich

2016-01-01

Recently we have discovered an IgG degrading enzyme of the endemic pig pathogen S. suis designated IgdE that is highly specific for porcine IgG. This protease is the founding member of a novel cysteine protease family assigned C113 in the MEROPS peptidase database. Bioinformatical analyses revealed putative members of the IgdE protease family in eight other Streptococcus species. The genes of the putative IgdE family proteases of S. agalactiae, S. porcinus, S. pseudoporcinus and S. equi subsp. zooepidemicus were cloned for production of recombinant protein into expression vectors. Recombinant proteins of all four IgdE family proteases were proteolytically active against IgG of the respective Streptococcus species hosts, but not against IgG from other tested species or other classes of immunoglobulins, thereby linking the substrate specificity to the known host tropism. The novel IgdE family proteases of S. agalactiae, S. pseudoporcinus and S. equi showed IgG subtype specificity, i.e. IgdE from S. agalactiae and S. pseudoporcinus cleaved human IgG1, while IgdE from S. equi was subtype specific for equine IgG7. Porcine IgG subtype specificities of the IgdE family proteases of S. porcinus and S. pseudoporcinus remain to be determined. Cleavage of porcine IgG by IgdE of S. pseudoporcinus is suggested to be an evolutionary remaining activity reflecting ancestry of the human pathogen to the porcine pathogen S. porcinus. The IgG subtype specificity of bacterial proteases indicates the special importance of these IgG subtypes in counteracting infection or colonization and opportunistic streptococci neutralize such antibodies through expression of IgdE family proteases as putative immune evasion factors. We suggest that IgdE family proteases might be valid vaccine targets against streptococci of both human and veterinary medical concerns and could also be of therapeutic as well as biotechnological use.

Inclusive photoproduction of rho and ω in the photon energy range 20 to 70 GeV

International Nuclear Information System (INIS)

Atkinson, M.; Laberrigue, J.; Levy, J.M.; La Vaissiere, C. de; Yiou, T.P.; Lassalle, J.C.; Patrick, G.N.; Storr, K.M.; Axon, T.J.; Barberis, D.; Brodbeck, T.J.; Brookes, G.R.; Bunn, J.J.; Bussey, P.J.; Clegg, A.B.; Dainton, J.B.; Davenport, M.; Dickinson, B.; Diekmann, B.; Donnachie, A.; Ellison, R.J.; Flower, P.; Hughes-Jones, R.E.; Hutton, J.S.; Ibbotson, M.; Jakob, H.P.; Jung, M.; Kemp, M.A.R.; Kumar, B.R.; Lafferty, G.D.; Lane, J.B.; Liebenau, V.; McClatchey, R.H.; Mercer, D.; Morris, J.A.G.; Morris, J.V.; Newton, D.; Paterson, C.; Paul, E.; Raine, C.; Reidenbach, M.; Rotscheidt, H.; Schloesser, A.; Sharp, P.H.; Skillicorn, I.O.; Smith, K.M.; Thompson, R.J.; Waite, A.P.; Worsell, M.F.

1984-01-01

Inclusive production of rho 0 , ω, and rhosup(+-) at low transverse momentum has been measured in γp collisions with photons of energy 20 to 70 GeV. The vector mesons have been studied as functions of the Feynman variable chisub(F), varying between -0.2 and 0.95, i.e. excluding the 'elastic' peaks of rho 0 and ω photoproduction. For chisub(F) 0 ) approx.= sigma (ω) approx.= 1/2[sigma(p + ) + sigma(p - )]. For chisub(F) > 0.6, it is observed that sigma(p 0 ) > sigma(ω) >=1/2[sigma(rho + )+sigma(rho - )] and the differences increase with increasing chisub(F). Over the rhosub(F) range -0.2 0 and ω production. (orig.)

The rhodopsin-transducin complex houses two distinct rhodopsin molecules.

Science.gov (United States)

Jastrzebska, Beata; Ringler, Philippe; Palczewski, Krzysztof; Engel, Andreas

2013-05-01

Upon illumination the visual receptor rhodopsin (Rho) transitions to the activated form Rho(∗), which binds the heterotrimeric G protein, transducin (Gt) causing GDP to GTP exchange and Gt dissociation. Using succinylated concanavalin A (sConA) as a probe, we visualized native Rho dimers solubilized in 1mM n-dodecyl-β-d-maltoside (DDM) and Rho monomers in 5mM DDM. By nucleotide depletion and affinity chromatography together with crosslinking and size exclusion chromatography, we trapped and purified nucleotide-free Rho(∗)·Gt and sConA-Rho(∗)·Gt complexes kept in solution by either DDM or lauryl-maltose-neopentyl-glycol (LMNG). The 3 D envelope calculated from projections of negatively stained Rho(∗)·Gt-LMNG complexes accommodated two Rho molecules, one Gt heterotrimer and a detergent belt. Visualization of triple sConA-Rho(∗)·Gt complexes unequivocally demonstrated a pentameric assembly of the Rho(∗)·Gt complex in which the photoactivated Rho(∗) dimer serves as a platform for binding the Gt heterotrimer. Importantly, individual monomers of the Rho(∗) dimer in the heteropentameric complex exhibited different capabilities for regeneration with either 11-cis or 9-cis-retinal. Copyright © 2013 Elsevier Inc. All rights reserved.

Measurement of the spin density matrix for the $\\rho^0$, $K^{*0}(892)$ and $\\phi$ produced in $Z^0$ Decays

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Abreu, P; Adye, T; Alekseev, G D; Alemany, R; Allport, P P; Almehed, S; Amaldi, Ugo; Amato, S; Andersson, P; Andreazza, A; Antilogus, P; Apel, W D; Arnoud, Y; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Bambade, P; Barão, F; Barbi, M S; Barbiellini, Guido; Bardin, Dimitri Yuri; Barker, G; Baroncelli, A; Bärring, O; Bates, M J; Battaglia, Marco; Baubillier, M; Baudot, J; Becks, K H; Begalli, M; Beillière, P; Belokopytov, Yu A; Benvenuti, Alberto C; Bérat, C; Berggren, M; Bertini, D; Bertrand, D; Besançon, M; Bianchi, F; Bigi, M; Bilenky, S M; Billoir, P; Bizouard, M A; Bloch, D; Blume, M; Bonesini, M; Bonivento, W; Booth, P S L; Borgland, A W; Borisov, G; Bosio, C; Botner, O; Boudinov, E; Bouquet, B; Bourdarios, C; Bowcock, T J V; Bozzo, M; Branchini, P; Brand, K D; Brenke, T; Brenner, R A; Bricman, C; Brown, R C A; Brückman, P; Brunet, J M; Bugge, L; Buran, T; Burgsmüller, T; Buschmann, P; Cabrera, S; Caccia, M; Calvi, M; Camacho-Rozas, A J; Camporesi, T; Canale, V; Canepa, M; Cao, F; Carena, F; Carroll, L; Caso, Carlo; Castillo-Gimenez, M V; Cattai, A; Cavallo, F R; Chabaud, V; Chapkin, M M; Charpentier, P; Chaussard, L; Checchia, P; Chelkov, G A; Chen, M; Chierici, R; Chliapnikov, P V; Chochula, P; Chorowicz, V; Chudoba, J; Cindro, V; Collins, P; Contri, R; Cortina, E; Cosme, G; Cossutti, F; Cowell, J H; Crawley, H B; Crennell, D J; Crosetti, G; Cuevas-Maestro, J; Czellar, S; Dahm, J; D'Almagne, B; Dam, M; Damgaard, G; Dauncey, P D; Davenport, Martyn; Da Silva, W; Deghorain, A; Della Ricca, G; Delpierre, P A; Demaria, N; De Angelis, A; de Boer, Wim; De Brabandere, S; De Clercq, C; La Vaissière, C de; De Lotto, B; De Min, A; De Paula, L S; Dijkstra, H; Di Ciaccio, Lucia; Di Diodato, A; Djannati, A; Dolbeau, J; Doroba, K; Dracos, M; Drees, J; Drees, K A; Dris, M; Durand, J D; Edsall, D M; Ehret, R; Eigen, G; Ekelöf, T J C; Ekspong, Gösta; Elsing, M; Engel, J P; Erzen, B; Espirito-Santo, M C; Falk, E; Fanourakis, G K; Fassouliotis, D; Feindt, Michael; Fenyuk, A; Ferrari, P; Ferrer, A; Fichet, S; Filippas-Tassos, A; Firestone, A; Fischer, P A; Föth, H; Fokitis, E; Fontanelli, F; Formenti, F; Franek, B J; Frodesen, A G; Frühwirth, R; Fulda-Quenzer, F; Fuster, J A; Galloni, A; Gamba, D; Gandelman, M; García, C; García, J; Gaspar, C; Gasparini, U; Gavillet, P; Gazis, E N; Gelé, D; Gerber, J P; Gerdyukov, L N; Gokieli, R; Golob, B; Gonçalves, P; Gopal, Gian P; Gorn, L; Górski, M; Guz, Yu; Gracco, Valerio; Graziani, E; Green, C; Grefrath, A; Gris, P; Grosdidier, G; Grzelak, K; Günther, M; Guy, J; Hahn, F; Hahn, S; Hajduk, Z; Hallgren, A; Hamacher, K; Harris, F J; Hedberg, V; Henriques, R P; Hernández, J J; Herquet, P; Herr, H; Hessing, T L; Heuser, J M; Higón, E; Holmgren, S O; Holt, P J; Holthuizen, D J; Hoorelbeke, S; Houlden, M A; Hrubec, Josef; Huet, K; Hultqvist, K; Jackson, J N; Jacobsson, R; Jalocha, P; Janik, R; Jarlskog, C; Jarlskog, G; Jarry, P; Jean-Marie, B; Johansson, E K; Jönsson, L B; Jönsson, P E; Joram, Christian; Juillot, P; Kaiser, M; Kapusta, F; Karafasoulis, K; Katsanevas, S; Katsoufis, E C; Keränen, R; Khokhlov, Yu A; Khomenko, B A; Khovanskii, N N; King, B J; Kjaer, N J; Klapp, O; Klein, H; Kluit, P M; Knoblauch, D; Kokkinias, P; Koratzinos, M; Korcyl, K; Kostyukhin, V; Kourkoumelis, C; Kuznetsov, O; Krammer, Manfred; Kreuter, C; Kronkvist, I J; Krstic, J; Krumshtein, Z; Krupinski, W; Kubinec, P; Kucewicz, W; Kurvinen, K L; Lacasta, C; Laktineh, I; Lamsa, J; Lanceri, L; Lane, D W; Langefeld, P; Laugier, J P; Lauhakangas, R; Leder, Gerhard; Ledroit, F; Lefébure, V; Legan, C K; Leisos, A; Leitner, R; Lemonne, J; Lenzen, Georg; Lepeltier, V; Lesiak, T; Libby, J; Liko, D; Lipniacka, A; Lippi, I; Lörstad, B; Loken, J G; López, J M; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J N; Maehlum, G; Mahon, J R; Maio, A; Malmgren, T G M; Malychev, V; Mandl, F; Marco, J; Marco, R P; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Martínez-Vidal, F; Martí i García, S; Masik, J; Matorras, F; Matteuzzi, C; Matthiae, Giorgio; Mazzucato, M; McCubbin, M L; McKay, R; McNulty, R; McPherson, G; Medbo, J; Meroni, C; Meyer, S; Meyer, W T; Myagkov, A; Michelotto, M; Migliore, E; Mirabito, L; Mitaroff, Winfried A; Mjörnmark, U; Moa, T; Møller, R; Mönig, K; Monge, M R; Morettini, P; Müller, H; Münich, K; Mulders, M; Mundim, L M; Murray, W J; Muryn, B; Myatt, Gerald; Myklebust, T; Naraghi, F; Navarria, Francesco Luigi; Navas, S; Nawrocki, K; Negri, P; Némécek, S; Neumann, W; Neumeister, N; Nicolaidou, R; Nielsen, B S; Nieuwenhuizen, M; Nikolaenko, V; Nikolenko, M; Niss, P; Nomerotski, A; Normand, Ainsley; Nygren, A; Oberschulte-Beckmann, W; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Orazi, G; Österberg, K; Ouraou, A; Paganini, P; Paganoni, M; Pain, R; Palka, H; Papadopoulou, T D; Papageorgiou, K; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Pegoraro, M; Peralta, L; Pernegger, H; Pernicka, Manfred; Perrotta, A; Petridou, C; Petrolini, A; Phillips, H T; Piana, G; Pierre, F; Pimenta, M; Podobnik, T; Podobrin, O; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Privitera, P; Pukhaeva, N; Pullia, Antonio; Radojicic, D; Ragazzi, S; Rahmani, H; Ratoff, P N; Read, A L; Reale, M; Rebecchi, P; Redaelli, N G; Regler, Meinhard; Reid, D; Reinhardt, R; Renton, P B; Resvanis, L K; Richard, F; Rídky, J; Rinaudo, G; Røhne, O M; Romero, A; Ronchese, P; Roos, L; Rosenberg, E I; Rosinsky, P; Roudeau, Patrick; Rovelli, T; Ruhlmann-Kleider, V; Ruiz, A; Rybicki, K; Saarikko, H; Sacquin, Yu; Sadovskii, A; Sajot, G; Salt, J; Sannino, M; Schneider, H; Schwickerath, U; Schyns, M A E; Sciolla, G; Scuri, F; Seager, P; Sedykh, Yu; Segar, A M; Seitz, A; Sekulin, R L; Serbelloni, L; Shellard, R C; Sheridan, A; Siegrist, P; Silvestre, R; Simonetto, F; Sissakian, A N; Skaali, T B; Smadja, G; Smirnov, N; Smirnova, O G; Smith, G R; Sokolov, A; Solovyanov, O; Sosnowski, R; Souza-Santos, D; Spassoff, Tz; Spiriti, E; Sponholz, P; Squarcia, S; Stampfer, D; Stanescu, C; Stanic, S; Stapnes, Steinar; Stavitski, I; Stevenson, K; Stocchi, A; Strauss, J; Strub, R; Stugu, B; Szczekowski, M; Szeptycka, M; Tabarelli de Fatis, T; Tavernet, J P; Tegenfeldt, F; Terranova, F; Thomas, J; Tilquin, A; Timmermans, J; Tkatchev, L G; Todorov, T; Todorova, S; Toet, D Z; Tomaradze, A G; Tonazzo, A; Tortora, L; Tranströmer, G; Treille, D; Tristram, G; Trombini, A; Troncon, C; Tsirou, A L; Turluer, M L; Tyapkin, I A; Tyndel, M; Tzamarias, S; Überschär, B; Ullaland, O; Uvarov, V; Valenti, G; Vallazza, E; van Apeldoorn, G W; van Dam, P; Van Eldik, J; Van Lysebetten, A; Vassilopoulos, N; Vegni, G; Ventura, L; Venus, W A; Verbeure, F; Verlato, M; Vertogradov, L S; Vilanova, D; Vincent, P; Vitale, L; Vlasov, E; Vodopyanov, A S; Vrba, V; Wahlen, H; Walck, C; Weiser, C; Wetherell, Alan M; Wicke, D; Wickens, J H; Wielers, M; Wilkinson, G R; Williams, W S C; Winter, M; Witek, M; Wlodek, T; Yi, J; Yip, K; Yushchenko, O P; Zach, F; Zaitsev, A; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zevgolatakos, E; Zimin, N I; Zucchelli, G C; Zumerle, G

1997-01-01

The spin density matrix elements for the $\\rho^0$, K$^{*0}(892)$ and $\\phi$ produced in hadronic Z$^0$ decays are measured in the DELPHI detector. There is no evidence for spin alignment of the K$^{*0}(892)$ and $\\phi$ in the region $x_p \\leq 0.3$ ($x_p = p/p_{beam}$), where $\\rho_{00} = 0.33 \\pm 0.05$ and $\\rho_{00} = 0.30 \\pm 0.04$, respectively. In the fragmentation region, $x_p \\geq 0.4$, there is some indication for spin alignment of the $\\rho^0$ and K$^{*0}(892)$, since $\\rho_{00} = 0.43 \\pm 0.05$ and $\\rho_{00} = 0.46 \\pm 0.08$, respectively. These values are compared with those found in meson-induced hadronic reactions. For the $\\phi$, $\\rho_{00} = 0.30 \\pm 0.04$ for $x_p \\geq 0.4$ and $0.55 \\pm 0.10$ for $x_p \\geq 0.7$. The off-diagonal spin density matrix element $\\rho_{1-1}$ is consistent with zero in all cases.

The apolipoprotein L family of programmed cell death and immunity genes rapidly evolved in primates at discrete sites of host-pathogen interactions.

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Smith, Eric E; Malik, Harmit S

2009-05-01

Apolipoprotein L1 (APOL1) is a human protein that confers immunity to Trypanosoma brucei infections but can be countered by a trypanosome-encoded antagonist SRA. APOL1 belongs to a family of programmed cell death genes whose proteins can initiate host apoptosis or autophagic death. We report here that all six members of the APOL gene family (APOL1-6) present in humans have rapidly evolved in simian primates. APOL6, furthermore, shows evidence of an adaptive sweep during recent human evolution. In each APOL gene tested, we found rapidly evolving codons in or adjacent to the SRA-interacting protein domain (SID), which is the domain of APOL1 that interacts with SRA. In APOL6, we also found a rapidly changing 13-amino-acid cluster in the membrane-addressing domain (MAD), which putatively functions as a pH sensor and regulator of cell death. We predict that APOL genes are antagonized by pathogens by at least two distinct mechanisms: SID antagonists, which include SRA, that interact with the SID of various APOL proteins, and MAD antagonists that interact with the MAD hinge base of APOL6. These antagonists either block or prematurely cause APOL-mediated programmed cell death of host cells to benefit the infecting pathogen. These putative interactions must occur inside host cells, in contrast to secreted APOL1 that trafficks to the trypanosome lysosome. Hence, the dynamic APOL gene family appears to be an important link between programmed cell death of host cells and immunity to pathogens.

Host-symbiont co-speciation and reductive genome evolution in gut symbiotic bacteria of acanthosomatid stinkbugs

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Kamagata Yoichi

2009-01-01

Full Text Available Abstract Background Host-symbiont co-speciation and reductive genome evolution have been commonly observed among obligate endocellular insect symbionts, while such examples have rarely been identified among extracellular ones, the only case reported being from gut symbiotic bacteria of stinkbugs of the family Plataspidae. Considering that gut symbiotic communities are vulnerable to invasion of foreign microbes, gut symbiotic associations have been thought to be evolutionarily not stable. Stinkbugs of the family Acanthosomatidae harbor a bacterial symbiont in the midgut crypts, the lumen of which is completely sealed off from the midgut main tract, thereby retaining the symbiont in the isolated cryptic cavities. We investigated histological, ecological, phylogenetic, and genomic aspects of the unique gut symbiosis of the acanthosomatid stinkbugs. Results Phylogenetic analyses showed that the acanthosomatid symbionts constitute a distinct clade in the γ-Proteobacteria, whose sister groups are the obligate endocellular symbionts of aphids Buchnera and the obligate gut symbionts of plataspid stinkbugs Ishikawaella. In addition to the midgut crypts, the symbionts were located in a pair of peculiar lubricating organs associated with the female ovipositor, by which the symbionts are vertically transmitted via egg surface contamination. The symbionts were detected not from ovaries but from deposited eggs, and surface sterilization of eggs resulted in symbiont-free hatchlings. The symbiont-free insects suffered retarded growth, high mortality, and abnormal morphology, suggesting important biological roles of the symbiont for the host insects. The symbiont phylogeny was generally concordant with the host phylogeny, indicating host-symbiont co-speciation over evolutionary time despite the extracellular association. Meanwhile, some local host-symbiont phylogenetic discrepancies were found, suggesting occasional horizontal symbiont transfers across the host

Measurement of Branching Fractions and CP-Violating Asymmetries in B -> rho+/-h-/+

CERN Document Server

Höcker, A

2003-01-01

We present measurements of branching fractions and CP-violating asymmetries in B sup 0 -> rho sup+- pi sup+- and B sup 0 -> rho sup - K sup + decays. The results are obtained from a data sample of 88.9 x 10 sup 6 UPSILON(4S) -> B(bar B) decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. From a time-dependent maximum likelihood fit we measure the charge-averaged branching fractions BETA(B sup 0 -> rho sup+- pi sup+-) = (22.6 +- 1.8 (stat) +- 2.2 (syst)) x 10 sup - sup 6 and BETA(B sup 0 -> rho sup - K sup +) = (7.3 sub - sub 1 sub . sub 2 sup + sup 1 sup . sup 3 +- 1.3) x 10 sup - sup 6; and the CP-violating charge asymmetries A sub C sub P suprho suppi = -0.18 +- 0.08 +- 0.03 and A sub C sub P suprho sup K = 0.28 +- 0.17 +- 0.08; the direct CP violation parameter C subrho subpi = 0.36 +- 0.18 +- 0.04 and the mixing-induced CP violation parameter S subrho subpi = 0.19 +- 0.24 +- 0.03; and the dilution parameters DELTA C subrho subpi = 0.28 sub - sub 0 sub . sub 1 sub 9 ...

Mutation analysis of inhibitory guanine nucleotide binding protein alpha (GNAI) loci in young and familial pituitary adenomas.

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Demir, Hande; Donner, Iikki; Kivipelto, Leena; Kuismin, Outi; Schalin-Jäntti, Camilla; De Menis, Ernesto; Karhu, Auli

2014-01-01

Pituitary adenomas are neoplasms of the anterior pituitary lobe and account for 15-20% of all intracranial tumors. Although most pituitary tumors are benign they can cause severe symptoms related to tumor size as well as hypopituitarism and/or hypersecretion of one or more pituitary hormones. Most pituitary adenomas are sporadic, but it has been estimated that 5% of patients have a familial background. Germline mutations of the tumor suppressor gene aryl hydrocarbon receptor-interacting protein (AIP) predispose to hereditary pituitary neoplasia. Recently, it has been demonstrated that AIP mutations predispose to pituitary tumorigenesis through defective inhibitory GTP binding protein (Gαi) signaling. This finding prompted us to examine whether germline loss-of-function mutations in inhibitory guanine nucleotide (GTP) binding protein alpha (GNAI) loci are involved in genetic predisposition of pituitary tumors. To our knowledge, this is the first time GNAI genes are sequenced in order to examine the occurrence of inactivating germline mutations. Thus far, only somatic gain-of-function hot-spot mutations have been studied in these loci. Here, we have analyzed the coding regions of GNAI1, GNAI2, and GNAI3 in a set of young sporadic somatotropinoma patients (n = 32; mean age of diagnosis 32 years) and familial index cases (n = 14), thus in patients with a disease phenotype similar to that observed in AIP mutation carriers. In addition, expression of Gαi proteins was studied in human growth hormone (GH), prolactin (PRL), adrenocorticotropic hormone (ACTH)-secreting and non-functional pituitary tumors. No pathogenic germline mutations affecting the Gαi proteins were detected. The result suggests that loss-of-function mutations of GNAI loci are rare or nonexistent in familial pituitary adenomas.

PHASE-RESOLVED TIMING ANALYSIS OF GRS 1915+105 IN ITS {rho} STATE

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Yan, Shu-Ping; Wang, Na; Ding, Guo-Qiang [Xinjiang Astronomical Observatory, Chinese Academy of Sciences, 150 Science 1-Street, Urumqi, Xinjiang 830011 (China); Qu, Jin-Lu, E-mail: yanshup@xao.ac.cn, E-mail: na.wang@xao.ac.cn [Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, 19B Yuquan Road, Beijing 100049 (China)

2013-04-10

We made a phase-resolved timing analysis of GRS 1915+105 in its {rho} state and obtained detailed {rho} cycle evolutions of the frequency, amplitude, and coherence of the low-frequency quasi-periodic oscillation (LFQPO). We combined our timing results with the spectral study by Neilsen et al. to perform an elaborate comparison analysis. Our analyses show that the LFQPO frequency does not scale with the inner disk radius, but it is related to the spectral index, indicating a possible correlation between the LFQPO and the corona. The LFQPO amplitude spectrum and other results are naturally explained by tying the LFQPO to the corona. The similarities of the spectra of variability parameters between the LFQPOs from {rho} state and those from more steady states indicate that the LFQPOs of GRS 1915+105 in very different states seem to share the same origin.

Trichomonas vaginalis NTPDase and ecto-5'-nucleotidase hydrolyze guanine nucleotides and increase extracellular guanosine levels under serum restriction.

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Menezes, Camila Braz; Durgante, Juliano; de Oliveira, Rafael Rodrigues; Dos Santos, Victor Hugo Jacks Mendes; Rodrigues, Luiz Frederico; Garcia, Solange Cristina; Dos Santos, Odelta; Tasca, Tiana

2016-05-01

Trichomonas vaginalis is the aethiologic agent of trichomoniasis, the most common non-viral sexually transmitted disease in the world. The purinergic signaling pathway is mediated by extracellular nucleotides and nucleosides that are involved in many biological effects as neurotransmission, immunomodulation and inflammation. Extracellular nucleotides can be hydrolyzed by a family of enzymes known as ectonucleotidases including the ecto-nucleoside triphosphate diphosphohydrolases (E-NTPDases) family which hydrolyses nucleosides triphosphate and diphosphate as preferential substrates and ecto-5'-nucleotidase which catalyzes the conversion of monophosphates into nucleosides. In T. vaginalis the E-NTPDase and ecto-5'-nucleotidase activities upon adenine nucleotides have already been characterized in intact trophozoites but little is known concerning guanine nucleotides and nucleoside. These enzymes may exert a crucial role on nucleoside generation, providing the purine sources for the synthesis de novo of these essential nutrients, sustaining parasite growth and survival. In this study, we investigated the hydrolysis profile of guanine-related nucleotides and nucleoside in intact trophozoites from long-term-grown and fresh clinical isolates of T. vaginalis. Knowing that guanine nucleotides are also substrates for T. vaginalis ectoenzymes, we evaluated the profile of nucleotides consumption and guanosine uptake in trophozoites submitted to a serum limitation condition. Results show that guanine nucleotides (GTP, GDP, GMP) were substrates for T. vaginalis ectonucleotidases, with expected kinetic parameters for this enzyme family. Different T. vaginalis isolates (two from the ATCC and nine fresh clinical isolates) presented a heterogeneous hydrolysis profile. The serum culture condition increased E-NTPDase and ecto-5'-nucleotidase activities with high consumption of extracellular GTP generating enhanced GDP, GMP and guanosine levels as demonstrated by HPLC, with final

Amphetamine activates Rho GTPase signaling to mediate dopamine transporter internalization and acute behavioral effects of amphetamine

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Wheeler, David S.; Underhill, Suzanne M.; Stolz, Donna B.; Murdoch, Geoffrey H.; Thiels, Edda; Romero, Guillermo; Amara, Susan G.

2015-01-01

Acute amphetamine (AMPH) exposure elevates extracellular dopamine through a variety of mechanisms that include inhibition of dopamine reuptake, depletion of vesicular stores, and facilitation of dopamine efflux across the plasma membrane. Recent work has shown that the DAT substrate AMPH, unlike cocaine and other nontransported blockers, can also stimulate endocytosis of the plasma membrane dopamine transporter (DAT). Here, we show that when AMPH enters the cytoplasm it rapidly stimulates DAT internalization through a dynamin-dependent, clathrin-independent process. This effect, which can be observed in transfected cells, cultured dopamine neurons, and midbrain slices, is mediated by activation of the small GTPase RhoA. Inhibition of RhoA activity with C3 exotoxin or a dominant-negative RhoA blocks AMPH-induced DAT internalization. These actions depend on AMPH entry into the cell and are blocked by the DAT inhibitor cocaine. AMPH also stimulates cAMP accumulation and PKA-dependent inactivation of RhoA, thus providing a mechanism whereby PKA- and RhoA-dependent signaling pathways can interact to regulate the timing and robustness of AMPH’s effects on DAT internalization. Consistent with this model, the activation of D1/D5 receptors that couple to PKA in dopamine neurons antagonizes RhoA activation, DAT internalization, and hyperlocomotion observed in mice after AMPH treatment. These observations support the existence of an unanticipated intracellular target that mediates the effects of AMPH on RhoA and cAMP signaling and suggest new pathways to target to disrupt AMPH action. PMID:26553986

RhoA/Rho kinase signaling regulates transforming growth factor-β1-induced chondrogenesis and actin organization of synovium-derived mesenchymal stem cells through interaction with the Smad pathway.

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Xu, Ting; Wu, Mengjie; Feng, Jianying; Lin, Xinping; Gu, Zhiyuan

2012-11-01

Recent studies have suggested that synovium-derived mesenchymal stem cells (SMSCs) may be promising candidates for tissue engineering and play an important role in cartilage regeneration. However, the mechanisms of SMSC chondrogenesis remain to be identified and characterized. The aim of this study was to evaluate the activation of the RhoA/Rho kinase (ROCK) pathway, as well as the manner by which it may contribute to chondrogenesis and the actin cytoskeletal organization of rat temporomandibular SMSCs in response to transforming growth factor-β1 (TGF-β1). Primary isolated SMSCs were treated with TGF-β1, and their actin organization was examined by fluorescein isothiocyanate-phalloidin staining. The specific biochemical inhibitors, C3 transferase, Y27632 and SB431542, were employed to evaluate the function of RhoA/ROCK and Smads. The effect of C3 transferase and Y27632 on the gene expression of chondrocyte-specific markers was evaluated by quantitative real-time polymerase chain reaction. To examine the effect of Y27632 on Smad2/3 phosphorylation induced by TGF-β1, western blot analysis was also performed. The stimulation of TGF-β1 in SMSCs resulted in the activation of the RhoA/ROCK pathway and concomitantly induced cytoskeletal reorganization, which was specifically blocked by C3 transferase and Y27632. The TGF-β-induced gene expression of Sox9, type I collagen, type II collagen and aggrecan was also inhibited by both C3 transferase and Y27632, at different levels. Y27632 treatment reduced the phosphorylation of Smad2/3 in a concentration-dependent manner. These results demonstrate the RhoA/ROCK activation regulates chondrocyte-specific gene transcription and cytoskeletal organization induced by TGF-β1 by interacting with the Smad pathway. This may have significant implications for the successful utilization of SMSCs as a cell source for articular cartilage tissue engineering.

RhoA, Rac1 and Cdc42 differentially regulate aSMA and collagen I expression in mesenchymal stem cells.

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Ge, Jianfeng; Burnier, Laurent; Adamopoulou, Maria; Kwa, Mei Qi; Schaks, Matthias; Rottner, Klemens; Brakebusch, Cord

2018-04-26

Mesenchymal stem cells (MSC) are suggested to be important progenitors of myofibroblasts in fibrosis. To understand the role of Rho GTPase signaling in TGFβ-induced myofibroblast differentiation of MSC, we generated a novel MSC line and descendants of it lacking functional Rho GTPases and Rho GTPase signaling components. Unexpectedly, our data revealed that Rho GTPase signaling is required for TGFβ-induced expression of αSMA, but not of collagen I α1 (col1a1). While loss of RhoA and Cdc42 reduced αSMA expression, ablation of the Rac1 gene had the opposite effect. Although actin polymerization and MRTFa were crucial for TGFβ-induced αSMA expression, neither Arp2/3 dependent actin polymerization nor cofilin dependent severing and depolymerization of F-actin were required. Instead, F-actin levels were dependent on cell contraction and TGFβ-induced actin polymerisation correlated with increased cell contraction mediated by RhoA and Cdc42. Finally, we observed impaired collagen I secretion in MSC lacking RhoA or Cdc42. These data give novel molecular insights into the role of Rho GTPases in TGFβ signaling and have implications for our understanding of MSC function in fibrosis. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

Cholesterol modulates the volume-regulated anion current in Ehrlich-Lettre ascites cells via effects on Rho and F-actin

DEFF Research Database (Denmark)

Klausen, Thomas Kjaer; Hougaard, Charlotte; Hoffmann, Else K

2006-01-01

swollen cells, this reduction was prevented by cholesterol depletion, which also increased isotonic Rho activity. Thrombin, which stimulates Rho and causes actin polymerization, potentiated VRAC in modestly swollen cells. VRAC activity was unaffected by inclusion of a water-soluble PtdIns(4,5)P(2......) analogue or a PtdIns(4,5)P(2)-blocking antibody in the pipette, or neomycin treatment to sequester PtdIns(4,5)P(2). It is suggested that in ELA cells, F-actin and Rho-Rho kinase modulate VRAC magnitude and activation rate, respectively, and that cholesterol depletion potentiates VRAC at least in part......The mechanisms controlling the volume-regulated anion current (VRAC) are incompletely elucidated. Here, we investigate the modulation of VRAC by cellular cholesterol and the potential involvement of F-actin, Rho, Rho kinase, and phosphatidylinositol-(4,5)-bisphosphate [PtdIns(4,5)P(2...

Microevolution of Helicobacter pylori during prolonged infection of single hosts and within families.

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Giovanna Morelli

2010-07-01

Full Text Available Our understanding of basic evolutionary processes in bacteria is still very limited. For example, multiple recent dating estimates are based on a universal inter-species molecular clock rate, but that rate was calibrated using estimates of geological dates that are no longer accepted. We therefore estimated the short-term rates of mutation and recombination in Helicobacter pylori by sequencing an average of 39,300 bp in 78 gene fragments from 97 isolates. These isolates included 34 pairs of sequential samples, which were sampled at intervals of 0.25 to 10.2 years. They also included single isolates from 29 individuals (average age: 45 years from 10 families. The accumulation of sequence diversity increased with time of separation in a clock-like manner in the sequential isolates. We used Approximate Bayesian Computation to estimate the rates of mutation, recombination, mean length of recombination tracts, and average diversity in those tracts. The estimates indicate that the short-term mutation rate is 1.4 x 10(-6 (serial isolates to 4.5 x 10(-6 (family isolates per nucleotide per year and that three times as many substitutions are introduced by recombination as by mutation. The long-term mutation rate over millennia is 5-17-fold lower, partly due to the removal of non-synonymous mutations due to purifying selection. Comparisons with the recent literature show that short-term mutation rates vary dramatically in different bacterial species and can span a range of several orders of magnitude.

Genetic diversity and distribution patterns of host insects of Caterpillar Fungus Ophiocordyceps sinensis in the Qinghai-Tibet Plateau.

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Quan, Qing-Mei; Chen, Ling-Ling; Wang, Xi; Li, Shan; Yang, Xiao-Ling; Zhu, Yun-Guo; Wang, Mu; Cheng, Zhou

2014-01-01

The caterpillar fungus Ophiocordyceps sinensis is one of the most valuable medicinal fungi in the world, and it requires host insects in family Hepialidae (Lepidoptera) to complete its life cycle. However, the genetic diversity and phylogeographic structures of the host insects remain to be explored. We analyzed the genetic diversity and temporal and spatial distribution patterns of genetic variation of the host insects throughout the O. sinensis distribution. Abundant haplotype and nucleotide diversity mainly existed in the areas of Nyingchi, ShangriLa, and around the edge of the Qinghai-Tibet Plateau, where are considered as the diversity center or micro-refuges of the host insects of O. sinensis. However, there was little genetic variation among host insects from 72.1% of all populations, indicating that the host species composition might be relatively simple in large-scale O. sinensis populations. All host insects are monophyletic except for those from four O. sinensis populations around Qinghai Lake. Significant phylogeographic structure (NST>GST, Pinsects, and the three major phylogenetic groups corresponded with specific geographical areas. The divergence of most host insects was estimated to have occurred at ca. 3.7 Ma, shortly before the rapid uplift of the QTP. The geographical distribution and star-like network of the haplotypes implied that most host insects were derived from the relicts of a once-widespread host that subsequently became fragmented. Neutrality tests, mismatch distribution analysis, and expansion time estimation confirmed that most host insects presented recent demographic expansions that began ca. 0.118 Ma in the late Pleistocene. Therefore, the genetic diversity and distribution of the present-day insects should be attributed to effects of the Qinghai-Tibet Plateau uplift and glacial advance/retreat cycles during the Quaternary ice age. These results provide valuable information to guide the protection and sustainable use of these host

RhoA signaling modulates cyclin D1 expression in human lung fibroblasts; implications for idiopathic pulmonary fibrosis

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Hoban PR

2006-06-01

Full Text Available Abstract Background Idiopathic Pulmonary Fibrosis (IPF is a debilitating disease characterized by exaggerated extracellular matrix deposition and aggressive lung structural remodeling. Disease pathogenesis is driven by fibroblastic foci formation, consequent on growth factor overexpression and myofibroblast proliferation. We have previously shown that both CTGF overexpression and myofibroblast formation in IPF cell lines are dependent on RhoA signaling. As RhoA-mediated regulation is also involved in cell cycle progression, we hypothesise that this pathway is key to lung fibroblast turnover through modulation of cyclin D1 kinetic expression. Methods Cyclin D1 expression was compared in primary IPF patient-derived fibroblasts and equivalent normal control cells. Quantitative real time PCR was employed to examine relative expression levels of cyclin D1 mRNA; protein expression was confirmed by western blotting. Effects of Rho signaling were investigated using transient transfection of constitutively active and dominant negative RhoA constructs as well as pharmacological inhibitors. Cellular proliferation of lung fibroblasts was determined by BrdU incorporation ELISA. To further explore RhoA regulation of cyclin D1 in lung fibroblasts and associated cell cycle progression, an established Rho inhibitor, Simvastatin, was incorporated in our studies. Results Cyclin D1 expression was upregulated in IPF compared to normal lung fibroblasts under exponential growth conditions (p Conclusion These findings report for the first time that cyclin D1 expression is deregulated in IPF through a RhoA dependent mechanism that influences lung fibroblast proliferation. This potentially unravels new molecular targets for future anti-IPF strategies; accordingly, Simvastatin inhibition of Rho-mediated cyclin D1 expression in IPF fibroblasts merits further exploitation.

Host phylogeny determines viral persistence and replication in novel hosts.

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Ben Longdon

2011-09-01

Full Text Available Pathogens switching to new hosts can result in the emergence of new infectious diseases, and determining which species are likely to be sources of such host shifts is essential to understanding disease threats to both humans and wildlife. However, the factors that determine whether a pathogen can infect a novel host are poorly understood. We have examined the ability of three host-specific RNA-viruses (Drosophila sigma viruses from the family Rhabdoviridae to persist and replicate in 51 different species of Drosophilidae. Using a novel analytical approach we found that the host phylogeny could explain most of the variation in viral replication and persistence between different host species. This effect is partly driven by viruses reaching a higher titre in those novel hosts most closely related to the original host. However, there is also a strong effect of host phylogeny that is independent of the distance from the original host, with viral titres being similar in groups of related hosts. Most of this effect could be explained by variation in general susceptibility to all three sigma viruses, as there is a strong phylogenetic correlation in the titres of the three viruses. These results suggest that the source of new emerging diseases may often be predictable from the host phylogeny, but that the effect may be more complex than simply causing most host shifts to occur between closely related hosts.

Mutant RBL mast cells defective in Fc epsilon RI signaling and lipid raft biosynthesis are reconstituted by activated Rho-family GTPases.

Science.gov (United States)

Field, K A; Apgar, J R; Hong-Geller, E; Siraganian, R P; Baird, B; Holowka, D

2000-10-01

Characterization of defects in a variant subline of RBL mast cells has revealed a biochemical event proximal to IgE receptor (Fc epsilon RI)-stimulated tyrosine phosphorylation that is required for multiple functional responses. This cell line, designated B6A4C1, is deficient in both Fc epsilon RI-mediated degranulation and biosynthesis of several lipid raft components. Agents that bypass receptor-mediated Ca(2+) influx stimulate strong degranulation responses in these variant cells. Cross-linking of IgE-Fc epsilon RI on these cells stimulates robust tyrosine phosphorylation but fails to mobilize a sustained Ca(2+) response. Fc epsilon RI-mediated inositol phosphate production is not detectable in these cells, and failure of adenosine receptors to mobilize Ca(2+) suggests a general deficiency in stimulated phospholipase C activity. Antigen stimulation of phospholipases A(2) and D is also defective. Infection of B6A4C1 cells with vaccinia virus constructs expressing constitutively active Rho family members Cdc42 and Rac restores antigen-stimulated degranulation, and active Cdc42 (but not active Rac) restores ganglioside and GPI expression. The results support the hypothesis that activation of Cdc42 and/or Rac is critical for Fc epsilon RI-mediated signaling that leads to Ca(2+) mobilization and degranulation. Furthermore, they suggest that Cdc42 plays an important role in the biosynthesis and expression of certain components of lipid rafts.

Genome-wide Comparative Analyses Reveal the Dynamic Evolution of Nucleotide-Binding Leucine-Rich Repeat Gene Family among Solanaceae Plants

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Eunyoung Seo

2016-08-01

Full Text Available Plants have evolved an elaborate innate immune system against invading pathogens. Within this system, intracellular nucleotide-binding leucine-rich repeat (NLR immune receptors are known play critical roles in effector-triggered immunity (ETI plant defense. We performed genome-wide identification and classification of NLR-coding sequences from the genomes of pepper, tomato, and potato using fixed criteria. We then compared genomic duplication and evolution features. We identified intact 267, 443, and 755 NLR-encoding genes in tomato, potato, and pepper genomes, respectively. Phylogenetic analyses and classification of Solanaceae NLRs revealed that the majority of NLR super family members fell into 14 subgroups, including a TIR-NLR (TNL subgroup and 13 non-TNL subgroups. Specific subgroups have expanded in each genome, with the expansion in pepper showing subgroup-specific physical clusters. Comparative analysis of duplications showed distinct duplication patterns within pepper and among Solanaceae plants suggesting subgroup- or species-specific gene duplication events after speciation, resulting in divergent evolution. Taken together, genome-wide analyses of NLR family members provide insights into their evolutionary history in Solanaceae. These findings also provide important foundational knowledge for understanding NLR evolution and will empower broader characterization of disease resistance genes to be used for crop breeding.

Involvement of Rho-kinase in cold ischemia-reperfusion injury after liver transplantation in rats.

Science.gov (United States)

Shiotani, Satoko; Shimada, Mitsuo; Suehiro, Taketoshi; Soejima, Yuji; Yosizumi, Tomoharu; Shimokawa, Hiroaki; Maehara, Yoshihiko

2004-08-15

Reperfusion of ischemic tissues is known to cause the generation of reactive oxygen species (ROS) with resultant tissue damage. However, the sources of ROS in reperfused tissues are not fully characterized. We hypothesized that the small GTPase Rho and its target effector Rho-kinase/ROK/ROCK are involved in the oxidative burst in reperfused tissue with resultant reperfusion injury. In an in vivo rat model of liver transplantation using cold ischemia for 12 hr followed by reperfusion, a specific Rho-kinase inhibitor, fasudil (30 mg/kg), was administered orally 1 hr before the transplantation. Fasudil suppressed the ischemia-reperfusion (I/R)-induced generation of ROS after reperfusion (P<0.01) and also suppressed the release of inflammatory cytokines (tumor necrosis factor-alpha, interleukin-1beta) 3 hr after reperfusion, resulting in a significant reduction of I/R-induced hepatocellular injury (P<0.05), necrosis, apoptosis (P<0.01), and neutrophil infiltration (P<0.0001) 12 hr after reperfusion. All animals receiving a graft without fasudil died within 3 days, whereas 40% of those receiving fasudil survived (P<0.001). The present study demonstrates that Rho-kinase-mediated production of ROS and inflammatory cytokines are substantially involved in the pathogenesis of hepatocellular necrosis and apoptosis induced by cold I/R in vivo and that Rho-kinase may be regarded as a novel therapeutic target for the disorder.

Rho A Regulates Epidermal Growth Factor-Induced Human Osteosarcoma MG63 Cell Migration

Directory of Open Access Journals (Sweden)

Jinyang Wang

2018-05-01

Full Text Available Osteosarcoma, the most common primary bone tumor, occurs most frequently in children and adolescents and has a 5-year survival rate, which is unsatisfactory. As epidermal growth factor receptor (EGFR positively correlates with TNM (tumor-node-metastasis stage in osteosarcoma, EGFR may play an important role in its progression. The purpose of this study was to explore potential mechanisms underlying this correlation. We found that EGF promotes MG63 cell migration and invasion as well as stress fiber formation via Rho A activation and that these effects can be reversed by inhibiting Rho A expression. In addition, molecules downstream of Rho A, including ROCK1, LIMK2, and Cofilin, are activated by EGF in MG63 cells, leading to actin stress fiber formation and cell migration. Moreover, inhibition of ROCK1, LIMK2, or Cofilin in MG63 cells using known inhibitors or short hairpin RNA (shRNA prevents actin stress fiber formation and cell migration. Thus, we conclude that Rho A/ROCK1/LIMK2/Cofilin signaling mediates actin microfilament formation in MG63 cells upon EGFR activation. This novel pathway provides a promising target for preventing osteosarcoma progression and for treating this cancer.

A single splice site mutation in human-specific ARHGAP11B causes basal progenitor amplification

Science.gov (United States)

Florio, Marta; Namba, Takashi; Pääbo, Svante; Hiller, Michael; Huttner, Wieland B.

2016-01-01

The gene ARHGAP11B promotes basal progenitor amplification and is implicated in neocortex expansion. It arose on the human evolutionary lineage by partial duplication of ARHGAP11A, which encodes a Rho guanosine triphosphatase–activating protein (RhoGAP). However, a lack of 55 nucleotides in ARHGAP11B mRNA leads to loss of RhoGAP activity by GAP domain truncation and addition of a human-specific carboxy-terminal amino acid sequence. We show that these 55 nucleotides are deleted by mRNA splicing due to a single C→G substitution that creates a novel splice donor site. We reconstructed an ancestral ARHGAP11B complementary DNA without this substitution. Ancestral ARHGAP11B exhibits RhoGAP activity but has no ability to increase basal progenitors during neocortex development. Hence, a single nucleotide substitution underlies the specific properties of ARHGAP11B that likely contributed to the evolutionary expansion of the human neocortex. PMID:27957544

Cdc42 and RhoA reveal different spatio-temporal dynamics upon local stimulation with Semaphorin-3A

Directory of Open Access Journals (Sweden)

Federico eIseppon

2015-08-01

Full Text Available Small RhoGTPases, such as Cdc42 and RhoA, are key players in integrating external cues and intracellular signaling pathways that regulate growth cone (GC motility. Indeed, Cdc42 is involved in actin polymerization and filopodia formation, whereas RhoA induces GC collapse and neurite retraction through actomyosin contraction. In this study we employed Förster Resonance Energy Transfer (FRET microscopy to study the spatio-temporal dynamics of Cdc42 and RhoA in GCs in response to local Semaphorin-3A stimulation obtained with lipid vesicles filled with Semaphorin-3A and positioned near the selected GC using optical tweezers. We found that Cdc42 and RhoA were activated at the leading edge of NG108-15 neuroblastoma cells during spontaneous cycles of protrusion and retraction, respectively. The release of Semaphorin-3A brought to a progressive activation of RhoA within 30 seconds from the stimulus in the central region of the GC that collapsed and retracted. In contrast, the same stimulation evoked waves of Cdc42 activation propagating away from the stimulated region. A more localized stimulation obtained with Sema3A coated beads placed on the GC, led to Cdc42 active waves that propagated in a retrograde manner with a mean period of 70 seconds, and followed by GC retraction. Therefore, Semaphorin-3A activates both Cdc42 and RhoA with a complex and different spatial-temporal dynamics.

ROCK and RHO Playlist for Preimplantation Development: Streaming to HIPPO Pathway and Apicobasal Polarity in the First Cell Differentiation.

Science.gov (United States)

Alarcon, Vernadeth B; Marikawa, Yusuke

2018-01-01

In placental mammalian development, the first cell differentiation produces two distinct lineages that emerge according to their position within the embryo: the trophectoderm (TE, placenta precursor) differentiates in the surface, while the inner cell mass (ICM, fetal body precursor) forms inside. Here, we discuss how such position-dependent lineage specifications are regulated by the RHOA subfamily of small GTPases and RHO-associated coiled-coil kinases (ROCK). Recent studies in mouse show that activities of RHO/ROCK are required to promote TE differentiation and to concomitantly suppress ICM formation. RHO/ROCK operate through the HIPPO signaling pathway, whose cell position-specific modulation is central to establishing unique gene expression profiles that confer cell fate. In particular, activities of RHO/ROCK are essential in outside cells to promote nuclear localization of transcriptional co-activators YAP/TAZ, the downstream effectors of HIPPO signaling. Nuclear localization of YAP/TAZ depends on the formation of apicobasal polarity in outside cells, which requires activities of RHO/ROCK. We propose models of how RHO/ROCK regulate lineage specification and lay out challenges for future investigations to deepen our understanding of the roles of RHO/ROCK in preimplantation development. Finally, as RHO/ROCK may be inhibited by certain pharmacological agents, we discuss their potential impact on human preimplantation development in relation to fertility preservation in women.

Induction of human microsomal prostaglandin E synthase 1 by activated oncogene RhoA GTPase in A549 human epithelial cancer cells

Energy Technology Data Exchange (ETDEWEB)

Choi, Hye Jin [Laboratory of Systems Mucosal Biomodulation, Department of Microbiology and Immunology, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Lee, Dong-Hyung [Department of Obstetrics and Gynecology, Medical Research Institute, Pusan National University, Busan (Korea, Republic of); Park, Seong-Hwan; Kim, Juil; Do, Kee Hun [Laboratory of Systems Mucosal Biomodulation, Department of Microbiology and Immunology, Pusan National University School of Medicine, Yangsan (Korea, Republic of); An, Tae Jin; Ahn, Young Sup; Park, Chung Berm [Department of Herbal Crop Research, NIHHS, RDA, Eumseong (Korea, Republic of); Moon, Yuseok, E-mail: moon@pnu.edu [Laboratory of Systems Mucosal Biomodulation, Department of Microbiology and Immunology, Pusan National University School of Medicine, Yangsan (Korea, Republic of); Medical Research Institute and Research Institute for Basic Sciences, Pusan National University, Busan (Korea, Republic of)

2011-09-30

Highlights: {yields} As a target of oncogene RhoA-linked signal, a prostaglandin metabolism is assessed. {yields} RhoA activation increases PGE{sub 2} levels and its metabolic enzyme mPGES-1. {yields} RhoA-activated NF-{kappa}B and EGR-1 are positively involved in mPGES-1 induction. -- Abstract: Oncogenic RhoA GTPase has been investigated as a mediator of pro-inflammatory responses and aggressive carcinogenesis. Among the various targets of RhoA-linked signals, pro-inflammatory prostaglandin E{sub 2} (PGE{sub 2}), a major prostaglandin metabolite, was assessed in epithelial cancer cells. RhoA activation increased PGE{sub 2} levels and gene expression of the rate-limiting PGE{sub 2} producing enzymes, cyclooxygenase-2 and microsomal prostaglandin E synthase 1 (mPGES-1). In particular, human mPGES-1 was induced by RhoA via transcriptional activation in control and interleukin (IL)-1{beta}-activated cancer cells. To address the involvement of potent signaling pathways in RhoA-activated mPGES-1 induction, various signaling inhibitors were screened for their effects on mPGES-1 promoter activity. RhoA activation enhanced basal and IL-1{beta}-mediated phosphorylated nuclear factor-{kappa}B and extracellular signal-regulated kinase1/2 proteins, all of which were positively involved in RhoA-induced gene expression of mPGES-1. As one potent down-stream transcription factor of ERK1/2 signals, early growth response gene 1 product also mediated RhoA-induced gene expression of mPGES-1 by enhancing transcriptional activity. Since oncogene-triggered PGE{sub 2} production is a critical modulator of epithelial tumor cells, RhoA-associated mPGES-1 represents a promising chemo-preventive or therapeutic target for epithelial inflammation and its associated cancers.

RPO41-independent maintenance of [rho-] mitochondrial DNA in Saccharomyces cerevisiae.

Science.gov (United States)

Fangman, W L; Henly, J W; Brewer, B J

1990-01-01

A subset of promoters in the mitochondrial DNA (mtDNA) of the yeast Saccharomyces cerevisiae has been proposed to participate in replication initiation, giving rise to a primer through site-specific cleavage of an RNA transcript. To test whether transcription is essential for mtDNA maintenance, we examined two simple mtDNA deletion ([rho-]) genomes in yeast cells. One genome (HS3324) contains a consensus promoter (ATATAAGTA) for the mitochondrial RNA polymerase encoded by the nuclear gene RPO41, and the other genome (4a) does not. As anticipated, in RPO41 cells transcripts from the HS3324 genome were more abundant than were transcripts from the 4a genome. When the RPO41 gene was disrupted, both [rho-] genomes were efficiently maintained. The level of transcripts from HS3324 mtDNA was decreased greater than 400-fold in cells carrying the RPO41 disrupted gene; however, the low-level transcripts from 4a mtDNA were undiminished. These results indicate that replication of [rho-] genomes can be initiated in the absence of wild-type levels of the RPO41-encoded RNA polymerase.

Diffractive Photoproduction of Rho Mesons with Large Momentum Transfer at HERA

CERN Document Server

Aktas, A.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Babaev, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.; Becker, J.; Beckingham, M.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, N.; Bizot, J.C.; Boenig, M.-O.; Boudry, V.; Bracinik, J.; Brandt, G.; Brisson, V.; Bruncko, D.; Busser, F.W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Contreras, J.G.; Coughlan, J.A.; Cox, B.E.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Dau, W.D.; Daum, K.; de Boer, Y.; Delcourt, B.; Del Degan, M.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, Guenter; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eliseev, A.; Elsen, E.; Essenov, S.; Falkewicz, A.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Finke, L.; Fleischer, M.; Fleischmann, P.; Flucke, G.; Fomenko, A.; Franke, G.; Frisson, T.; Gabathuler, E.; Garutti, E.; Gayler, J.; Gerlich, C.; Ghazaryan, Samvel; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Grab, C.; Greenshaw, T.; Gregori, M.; Grell, B.R.; Grindhammer, G.; Gwilliam, C.; Haidt, D.; Hajduk, L.; Hansson, M.; Heinzelmann, G.; Henderson, R.C.W.; Henschel, H.; Herrera, G.; Hildebrandt, M.; Hiller, K.H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Hreus, T.; Hussain, S.; Ibbotson, M.; Ismail, M.; Jacquet, M.; Janauschek, L.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, D.P.; Jung, Andreas Werner; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I.R.; Kiesling, Christian M.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knies, G.; Knutsson, A.; Korbel, V.; Kostka, P.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Kruger, K.; Landon, M.P.J.; Lange, W.; Lastovicka, T.; Lastovicka-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Lobodzinska, E.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.-I.; Lueders, H.; Luke, D.; Lux, T.; Lytkin, L.; Makankine, A.; Malden, N.; Malinovski, E.; Mangano, S.; Marage, P.; Marshall, R.; Martisikova, M.; Martyn, H.-U.; Maxfield, S.J.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Milstead, D.; Mladenov, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, Matthias Ulrich; Muller, K.; Murin, P.; Nankov, K.; Naroska, B.; Naumann, Th.; Newman, Paul R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J.E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Papadopoulou, T.; Pascaud, C.; Patel, G.D.; Peng, H.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Pitzl, D.; Placakyte, R.; Portheault, B.; Povh, B.; Prideaux, P.; Rahmat, A.J.; Raicevic, N.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D.P.C.; Sauvan, E.; Schatzel, S.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schoning, A.; Schultz-Coulon, H.C.; Sefkow, F.; Shaw-West, R.N.; Sheviakov, I.; Shtarkov, L.N.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, Arnd E.; Steder, M.; Stella, B.; Stiewe, J.; Straumann, U.; Sunar, D.; Tchoulakov, V.; Thompson, Graham; Thompson, P.D.; Toll, T.; Tomasz, F.; Traynor, D.; Truol, P.; Tsakov, I.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, K.; Urban, Marcel; Usik, A.; Utkin, D.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vargas Trevino, A.; Vazdik, Ya.; Veelken, C.; Vinokurova, S.; Volchinski, V.; Wacker, K.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Wessels, M.; Wessling, B.; Wissing, Ch.; Wolf, R.; Wunsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zhu, Y.C.; Zimmermann, J.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

2006-01-01

The diffractive photoproduction of rho mesons, e p \\to e rho Y, with large momentum transfer squared at the proton vertex, |t|, is studied with the H1 detector at HERA using an integrated luminosity of 20.1 pb^{-1}. The photon-proton centre of mass energy spans the range 75 < W < 95 GeV, the photon virtuality is restricted to Q^2 < 0.01 GeV^2 and the mass M_Y of the proton remnant is below 5 GeV. The t dependence of the cross section is measured for the range 1.5 < |t| < 10.0 GeV^2 and is well described by a power law, dsigma/ d|t| \\propto |t|^{-n}. The spin density matrix elements, which provide information on the helicity structure of the interaction, are extracted using measurements of angular distributions of the rho decay products. The data indicate a violation of s-channel helicity conservation, with contributions from both single and double helicity-flip being observed. The results are compared to the predictions of perturbative QCD models.

Crystal structure and novel recognition motif of rho ADP-ribosylating C3 exoenzyme from Clostridium botulinum: structural insights for recognition specificity and catalysis.

Science.gov (United States)

Han, S; Arvai, A S; Clancy, S B; Tainer, J A

2001-01-05

Clostridium botulinum C3 exoenzyme inactivates the small GTP-binding protein family Rho by ADP-ribosylating asparagine 41, which depolymerizes the actin cytoskeleton. C3 thus represents a major family of the bacterial toxins that transfer the ADP-ribose moiety of NAD to specific amino acids in acceptor proteins to modify key biological activities in eukaryotic cells, including protein synthesis, differentiation, transformation, and intracellular signaling. The 1.7 A resolution C3 exoenzyme structure establishes the conserved features of the core NAD-binding beta-sandwich fold with other ADP-ribosylating toxins despite little sequence conservation. Importantly, the central core of the C3 exoenzyme structure is distinguished by the absence of an active site loop observed in many other ADP-ribosylating toxins. Unlike the ADP-ribosylating toxins that possess the active site loop near the central core, the C3 exoenzyme replaces the active site loop with an alpha-helix, alpha3. Moreover, structural and sequence similarities with the catalytic domain of vegetative insecticidal protein 2 (VIP2), an actin ADP-ribosyltransferase, unexpectedly implicates two adjacent, protruding turns, which join beta5 and beta6 of the toxin core fold, as a novel recognition specificity motif for this newly defined toxin family. Turn 1 evidently positions the solvent-exposed, aromatic side-chain of Phe209 to interact with the hydrophobic region of Rho adjacent to its GTP-binding site. Turn 2 evidently both places the Gln212 side-chain for hydrogen bonding to recognize Rho Asn41 for nucleophilic attack on the anomeric carbon of NAD ribose and holds the key Glu214 catalytic side-chain in the adjacent catalytic pocket. This proposed bipartite ADP-ribosylating toxin turn-turn (ARTT) motif places the VIP2 and C3 toxin classes into a single ARTT family characterized by analogous target protein recognition via turn 1 aromatic and turn 2 hydrogen-bonding side-chain moieties. Turn 2 centrally anchors

Control of HIV replication in astrocytes by a family of highly conserved host proteins with a common Rev-interacting domain (Risp).

Science.gov (United States)

Vincendeau, Michelle; Kramer, Susanne; Hadian, Kamyar; Rothenaigner, Ina; Bell, Jeanne; Hauck, Stefanie M; Bickel, Christian; Nagel, Daniel; Kremmer, Elisabeth; Werner, Thomas; Leib-Mösch, Christine; Brack-Werner, Ruth

2010-10-23

In human astrocytes, restriction of HIV replication involves inhibition of HIV Rev activity. We previously identified a Rev-interacting human protein fragment (16.4.1) that can reduce Rev activity. The 16.4.1 sequence is contained in a group of highly similar host cell proteins, which we call the Risp family. Here we investigate whether the Risp family is connected to HIV replication in astrocytes. Cell/tissue lysates were analyzed for Risp expression by western blot with various anti-Risp antibodies. The interaction of astrocytic Risp members with Rev was investigated by affinity chromatography. Astrocytes were transfected with expression plasmids containing cDNAs encoding full-length Risp or the isolated 16.4.1 region for Risp overexpression or with siRNAs designed for Risp knock-down. Rev activity was investigated with a Rev-reporter assay. RNA levels were quantified by real-time RT-PCR, HIV Gag levels by p24ELISA. Expression of the Risp family was demonstrated in human brain tissues and astrocytes. Astrocytes were shown to produce Risp family members that interact with Rev. Production of HIV Gag proteins and Rev-dependent RNAs in persistently infected astrocytes increased upon Risp knock-down and decreased upon Risp overexpression. Risp knock-down increased Rev activity and raised proportions of Rev proteins in the nucleus of astrocytes. Our results link the Risp family to restriction of HIV production and inhibition of Rev activity in astrocytes. We conclude that the Risp family represents a novel family of host factors that can control HIV replication and may be important for the containment of HIV infection in brain reservoirs.

A Study of Spin Alignment of $\\rho(770)^{\\pm}$ and $\\omega(782)$ Mesons in Hadronic $Z^{0}$ Decays

CERN Document Server

Abbiendi, G.; Alexander, G.; Allison, John; Altekamp, N.; Anderson, K.J.; Anderson, S.; Arcelli, S.; Asai, S.; Ashby, S.F.; Axen, D.; Azuelos, G.; Ball, A.H.; Barberio, E.; Barlow, Roger J.; Batley, J.R.; Baumann, S.; Bechtluft, J.; Behnke, T.; Bell, Kenneth Watson; Bella, G.; Bellerive, A.; Bentvelsen, S.; Bethke, S.; Betts, S.; Biebel, O.; Biguzzi, A.; Bloodworth, I.J.; Bock, P.; Bohme, J.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Bright-Thomas, P.; Brigliadori, L.; Brown, Robert M.; Burckhart, H.J.; Capiluppi, P.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Chrisman, D.; Ciocca, C.; Clarke, P.E.L.; Clay, E.; Cohen, I.; Conboy, J.E.; Cooke, O.C.; Couchman, J.; Couyoumtzelis, C.; Coxe, R.L.; Cuffiani, M.; Dado, S.; Dallavalle, G.Marco; Davis, R.; De Jong, S.; De Roeck, A.; Dervan, P.; Desch, K.; Dienes, B.; Dixit, M.S.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Estabrooks, P.G.; Etzion, E.; Fabbri, F.; Fanfani, A.; Fanti, M.; Faust, A.A.; Feld, L.; Fiedler, F.; Fierro, M.; Fleck, I.; Frey, A.; Furtjes, A.; Futyan, D.I.; Gagnon, P.; Gary, J.W.; Gascon, J.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Gibson, V.; Gibson, W.R.; Gingrich, D.M.; Glenzinski, D.; Goldberg, J.; Gorn, W.; Grandi, C.; Graham, K.; Gross, E.; Grunhaus, J.; Gruwe, M.; Hajdu, C.; Hanson, G.G.; Hansroul, M.; Hapke, M.; Harder, K.; Harel, A.; Hargrove, C.K.; Harin-Dirac, M.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herten, G.; Heuer, R.D.; Hildreth, M.D.; Hill, J.C.; Hobson, P.R.; Hocker, James Andrew; Hoffman, Kara Dion; Homer, R.J.; Honma, A.K.; Horvath, D.; Hossain, K.R.; Howard, R.; Huntemeyer, P.; Igo-Kemenes, P.; Imrie, D.C.; Ishii, K.; Jacob, F.R.; Jawahery, A.; Jeremie, H.; Jimack, M.; Jones, C.R.; Jovanovic, P.; Junk, T.R.; Kanaya, N.; Kanzaki, J.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Kayal, P.I.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kim, D.H.; Klier, A.; Kobayashi, T.; Kobel, M.; Kokott, T.P.; Kolrep, M.; Komamiya, S.; Kowalewski, Robert V.; Kress, T.; Krieger, P.; von Krogh, J.; Kuhl, T.; Kyberd, P.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Lauber, J.; Lawson, I.; Layter, J.G.; Lellouch, D.; Letts, J.; Levinson, L.; Liebisch, R.; List, B.; Littlewood, C.; Lloyd, A.W.; Lloyd, S.L.; Loebinger, F.K.; Long, G.D.; Losty, M.J.; Lu, J.; Ludwig, J.; Lui, D.; Macchiolo, A.; Macpherson, A.; Mader, W.; Mannelli, M.; Marcellini, S.; Martin, A.J.; Martin, J.P.; Martinez, G.; Mashimo, T.; Mattig, Peter; McDonald, W.John; McKenna, J.; Mckigney, E.A.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Mendez-Lorenzo, P.; Merritt, F.S.; Mes, H.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mohr, W.; Montanari, A.; Mori, T.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oakham, F.G.; Odorici, F.; Ogren, H.O.; Okpara, A.; Oreglia, M.J.; Orito, S.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Patt, J.; Perez-Ochoa, R.; Petzold, S.; Pfeifenschneider, P.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poffenberger, P.; Poli, B.; Polok, J.; Przybycien, M.; Quadt, A.; Rembser, C.; Rick, H.; Robertson, S.; Robins, S.A.; Rodning, N.; Roney, J.M.; Rosati, S.; Roscoe, K.; Rossi, A.M.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D.R.; Sachs, K.; Saeki, T.; Sahr, O.; Sang, W.M.; Sarkisian, E.K.G.; Sbarra, C.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schmitt, S.; Schoning, A.; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Siroli, G.P.; Sittler, A.; Skuja, A.; Smith, A.M.; Snow, G.A.; Sobie, R.; Soldner-Rembold, S.; Spagnolo, S.; Sproston, M.; Stahl, A.; Stephens, K.; Steuerer, J.; Stoll, K.; Strom, David M.; Strohmer, R.; Surrow, B.; Talbot, S.D.; Taras, P.; Tarem, S.; Teuscher, R.; Thiergen, M.; Thomas, J.; Thomson, M.A.; Torrence, E.; Towers, S.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Van Kooten, Rick J.; Vannerem, P.; Verzocchi, M.; Voss, H.; Wackerle, F.; Wagner, A.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wermes, N.; Wetterling, D.; White, J.S.; Wilson, G.W.; Wilson, J.A.; Wyatt, T.R.; Yamashita, S.; Zacek, V.; Zer-Zion, D.

2000-01-01

The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding to a statistical mix of helicity -1, 0 and +1 states. For the highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00] values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114, respectively. These results are compared to measurements of other vector mesons.

P190B RhoGAP Regulates Chromosome Segregation in Cancer Cells

International Nuclear Information System (INIS)

Hwang, Melissa; Peddibhotla, Sirisha; McHenry, Peter; Chang, Peggy; Yochum, Zachary; Park, Ko Un; Sears, James Cooper; Vargo-Gogola, Tracy

2012-01-01

Rho GTPases are overexpressed and hyperactivated in many cancers, including breast cancer. Rho proteins, as well as their regulators and effectors, have been implicated in mitosis, and their altered expression promotes mitotic defects and aneuploidy. Previously, we demonstrated that p190B Rho GTPase activating protein (RhoGAP) deficiency inhibits ErbB2-induced mammary tumor formation in mice. Here we describe a novel role for p190B as a regulator of mitosis. We found that p190B localized to centrosomes during interphase and mitosis, and that it is differentially phosphorylated during mitosis. Knockdown of p190B expression in MCF-7 and Hela cells increased the incidence of aberrant microtubule-kinetochore attachments at metaphase, lagging chromosomes at anaphase, and micronucleation, all of which are indicative of aneuploidy. Cell cycle analysis of p190B deficient MCF-7 cells revealed a significant increase in apoptotic cells with a concomitant decrease in cells in G1 and S phase, suggesting that p190B deficient cells die at the G1 to S transition. Chemical inhibition of the Rac GTPase during mitosis reduced the incidence of lagging chromosomes in p190B knockdown cells to levels detected in control cells, suggesting that aberrant Rac activity in the absence of p190B promotes chromosome segregation defects. Taken together, these data suggest that p190B regulates chromosome segregation and apoptosis in cancer cells. We propose that disruption of mitosis may be one mechanism by which p190B deficiency inhibits tumorigenesis

P190B RhoGAP Regulates Chromosome Segregation in Cancer Cells

Energy Technology Data Exchange (ETDEWEB)

Hwang, Melissa [Department of Biochemistry and Molecular Biology and the Indiana University Simon Cancer Center, Indiana University School of Medicine, 1234 Notre Dame Avenue, South Bend, IN 46617 (United States); Peddibhotla, Sirisha [Department of Molecular and Human Genetics, Baylor College of Medicine, John P. McGovern Campus, NABS-0250, Houston, TX 77030 (United States); McHenry, Peter [Department of Biology, Southwestern Adventist University, 100 W. Hillcrest, Keene, TX 76059 (United States); Chang, Peggy; Yochum, Zachary; Park, Ko Un; Sears, James Cooper; Vargo-Gogola, Tracy, E-mail: vargo-gogola.1@nd.edu [Department of Biochemistry and Molecular Biology and the Indiana University Simon Cancer Center, Indiana University School of Medicine, 1234 Notre Dame Avenue, South Bend, IN 46617 (United States)

2012-04-25

Rho GTPases are overexpressed and hyperactivated in many cancers, including breast cancer. Rho proteins, as well as their regulators and effectors, have been implicated in mitosis, and their altered expression promotes mitotic defects and aneuploidy. Previously, we demonstrated that p190B Rho GTPase activating protein (RhoGAP) deficiency inhibits ErbB2-induced mammary tumor formation in mice. Here we describe a novel role for p190B as a regulator of mitosis. We found that p190B localized to centrosomes during interphase and mitosis, and that it is differentially phosphorylated during mitosis. Knockdown of p190B expression in MCF-7 and Hela cells increased the incidence of aberrant microtubule-kinetochore attachments at metaphase, lagging chromosomes at anaphase, and micronucleation, all of which are indicative of aneuploidy. Cell cycle analysis of p190B deficient MCF-7 cells revealed a significant increase in apoptotic cells with a concomitant decrease in cells in G1 and S phase, suggesting that p190B deficient cells die at the G1 to S transition. Chemical inhibition of the Rac GTPase during mitosis reduced the incidence of lagging chromosomes in p190B knockdown cells to levels detected in control cells, suggesting that aberrant Rac activity in the absence of p190B promotes chromosome segregation defects. Taken together, these data suggest that p190B regulates chromosome segregation and apoptosis in cancer cells. We propose that disruption of mitosis may be one mechanism by which p190B deficiency inhibits tumorigenesis.

Comparisons of actin filament disruptors and Rho kinase inhibitors as potential antiglaucoma medications

OpenAIRE

Tian, Baohe; Kaufman, Paul L

2012-01-01

Dynamics of the actin cytoskeleton in the trabecular meshwork play a crucial role in the regulation of trabecular outflow resistance. The actin filament disruptors and Rho kinase inhibitors affect the dynamics of the actomyosin system by either disrupting the actin filaments or inhibiting the Rho kinase-activated cellular contractility. Both approaches induce similar morphological changes and resistance decreases in the trabecular outflow pathway, and thus both have potential as antiglaucoma ...

QCD and resonance physics. The rho-ω mixing

International Nuclear Information System (INIS)

Shifman, M.A.; Vainshtein, A.I.; Zakharov, V.I.

1978-01-01

The QCD-based approach to the resonance physics proposed earlier is extended to cover the rho-ω mixing problem. A two-point function relevant to the problem with account of nonperturbative contributions is considered. The sum rules are derived and related phenomenology is introduced. The rho-ω interference is found to be due to the relatively strong isotopic symmetry breaking in the quark masses, and a solution with msub(u) = 0, msub(d) not equal to 0 seems to be ruled out. It is shown that virtual photon exchanges alone can not explain the observed value of the mixing parameter. The phenomenon gets a natural explanation if one assumes a large isotopic symmetry violation in the mechanical quark masses, (msub(d) - msub(u))/(msub(d) + msub(u)) approximately 0.3. This number is close to that resulting from the well-known pseudoscalar meson analysis. Unlike the latter, the result, however, does not assume an exact SU(3)sub(flavor) symmetry in vacuum-to-vacuum matrix elements

Mechanism of RhoB/FTI Action in Breast Cancer

National Research Council Canada - National Science Library

Kamasani, Uma R; Prendergast, George

2004-01-01

.... What factors dictate FTI efficacy? In this period, we advanced our studies of the role of cyclin B1, a key regulator of mitosis, as a critical target for RhoB suppression in FTI-induced apoptosis...

Mechanism of RhoB/FTI Action in Breast Cancer

National Research Council Canada - National Science Library

Kamasani, Uma

2003-01-01

.... What factors dictate FTI efficacy? Work completed earlier in this project defined rules for RhoB and its downstream effector kinase PRK in mediating growth inhibition by FTI in epithelial cells, including human breast epithelial cells...

Discovery of a polyomavirus in European badgers (Meles meles) and the evolution of host range in the family Polyomaviridae.

Science.gov (United States)

Hill, Sarah C; Murphy, Aisling A; Cotten, Matthew; Palser, Anne L; Benson, Phillip; Lesellier, Sandrine; Gormley, Eamonn; Richomme, Céline; Grierson, Sylvia; Bhuachalla, Deirdre Ni; Chambers, Mark; Kellam, Paul; Boschiroli, María-Laura; Ehlers, Bernhard; Jarvis, Michael A; Pybus, Oliver G

2015-06-01

Polyomaviruses infect a diverse range of mammalian and avian hosts, and are associated with a variety of symptoms. However, it is unknown whether the viruses are found in all mammalian families and the evolutionary history of the polyomaviruses is still unclear. Here, we report the discovery of a novel polyomavirus in the European badger (Meles meles), which to our knowledge represents the first polyomavirus to be characterized in the family Mustelidae, and within a European carnivoran. Although the virus was discovered serendipitously in the supernatant of a cell culture inoculated with badger material, we subsequently confirmed its presence in wild badgers. The European badger polyomavirus was tentatively named Meles meles polyomavirus 1 (MmelPyV1). The genome is 5187 bp long and encodes proteins typical of polyomaviruses. Phylogenetic analyses including all known polyomavirus genomes consistently group MmelPyV1 with California sea lion polyomavirus 1 across all regions of the genome. Further evolutionary analyses revealed phylogenetic discordance amongst polyomavirus genome regions, possibly arising from evolutionary rate heterogeneity, and a complex association between polyomavirus phylogeny and host taxonomic groups.

Aquaporin family genes exhibit developmentally-regulated and host-dependent transcription patterns in the sea louse Caligus rogercresseyi.

Science.gov (United States)

Farlora, Rodolfo; Valenzuela-Muñoz, Valentina; Chávez-Mardones, Jacqueline; Gallardo-Escárate, Cristian

2016-07-01

Aquaporins are small integral membrane proteins that function as pore channels for the transport of water and other small solutes across the cell membrane. Considering the important roles of these proteins in several biological processes, including host-parasite interactions, there has been increased research on aquaporin proteins recently. The present study expands on the knowledge of aquaporin family genes in parasitic copepods, examining diversity and expression during the ontogeny of the sea louse Caligus rogercresseyi. Furthermore, aquaporin expression was evaluated during the early infestation of Atlantic (Salmo salar) and Coho salmon (Oncorhynchus kisutch). Deep transcriptome sequencing data revealed eight full length and two partial open reading frames belonging to the aquaporin protein family. Clustering analyses with identified Caligidae sequences revealed three major clades of aquaglyceroporins (Cr-Glp), classical aquaporin channels (Cr-Bib and Cr-PripL), and unorthodox aquaporins (Cr-Aqp12-like). In silico analysis revealed differential expression of aquaporin genes between developmental stages and between sexes. Male-biased expression of Cr-Glp1_v1 and female-biased expression of Cr-Bib were further confirmed in adults by RT-qPCR. Additionally, gene expressions were measured for seven aquaporins during the early infestation stage. The majority of aquaporin genes showed significant differential transcription expressions between sea lice parasitizing different hosts, with Atlantic salmon sea lice exhibiting overall reduced expression as compared to Coho salmon. The observed differences in the regulation of aquaporin genes may reveal osmoregulatory adaptations associated with nutrient ingestion and metabolite waste export, exposing complex host-parasite relationships in C. rogercresseyi. Copyright © 2016 Elsevier B.V. All rights reserved.

Increased RhoA prenylation in the loechrig (loe mutant leads to progressive neurodegeneration.

Directory of Open Access Journals (Sweden)

Mandy Cook

Full Text Available The Drosophila mutant loechrig (loe shows age-dependent degeneration of the nervous system and is caused by the loss of a neuronal isoform of the AMP-activated protein kinase (AMPK γ-subunit (also known as SNF4Aγ. The trimeric AMPK complex is activated by low energy levels and metabolic insults and regulates multiple important signal pathways that control cell metabolism. A well-known downstream target of AMPK is hydroxyl-methylglutaryl-CoA reductase (HMGR, a key enzyme in isoprenoid synthesis, and we have previously shown that HMGR genetically interacts with loe and affects the severity of the degenerative phenotype. Prenylation of proteins like small G-proteins is an important posttranslational modification providing lipid moieties that allow the association of these proteins with membranes, thereby facilitating their subsequent activation. Rho proteins have been extensively studied in neuronal outgrowth, however, much less is known about their function in neuronal maintenance. Here we show that the loe mutation interferes with isoprenoid synthesis, leading to increased prenylation of the small GTPase Rho1, the fly orthologue of vertebrate RhoA. We also demonstrate that increased prenylation and Rho1 activity causes neurodegeneration and aggravates the behavioral and degenerative phenotypes of loe. Because we cannot detect defects in the development of the central nervous system in loe, this suggests that loe only interferes with the function of the RhoA pathway in maintaining neuronal integrity during adulthood. In addition, our results show that alterations in isoprenoids can result in progressive neurodegeneration, supporting findings in vertebrates that prenylation may play a role in neurodegenerative diseases like Alzheimer's Disease.

Measurement of the CKM Angle Alpha at the BABAR Detector Using B Meson Decays to Rho Final States

Energy Technology Data Exchange (ETDEWEB)

Mihalyi, Attila; /Wisconsin U., Madison

2006-10-16

This thesis contains the results of an analysis of B{sup 0} {yields} {rho}{sup +}{rho}{sup -} using 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. From a fitted signal yield of 617 {+-} 52 events, the longitudinal polarizations fraction, f{sub L}, of the decay is measured to be 0.978 {+-} 0.014(stat){sub -0.029}{sup +0.021}(syst). The nearly fully longitudinal dominance of the B{sup 0} {yields} {rho}{sup +}{rho}{sup -} decay allows for a measurement of the time dependent CP parameters S{sub L} and C{sub L}, where the first parameter is sensitive to mixing induced CP violation and the second one to direct CP violation. From the same signal yield, these values are found to be S{sub L} = -0.33 {+-} 0.24(stat){sub -0.14}{sup +0.08}(syst) and C{sub L} = - 0.03 {+-} 0.18(stat) {+-} 0.09(syst). The CKM angle {alpha} is then determined, using these results and the branching fractions and polarizations of the decays B{sup 0} {yields} {rho}{sup 0}{rho}{sup 0} and B{sup +} {yields} {rho}{sup +}{rho}{sup 0}. This measurement is done with an isospin analysis, in which a triangle is constructed from the isospin amplitudes of these three decay modes. A {chi}{sup 2} expression that includes the measured quantities expressed as the lengths of the sides of the isospin triangles is constructed and minimized to determine a confidence level on {alpha}. Selecting the solution compatible with the Standard Model, one obtains {alpha} = 100{sup o} {+-} 13{sup o}.

Abnormal Activation of RhoA/ROCK-I Signaling in Junctional Zone Smooth Muscle Cells of Patients With Adenomyosis.

Science.gov (United States)

Wang, S; Duan, H; Zhang, Y; Sun, F Q

2016-03-01

Adenomyosis (ADS) is a common estrogen-dependent gynecological disease with unknown etiology. The RhoA/Rho-kinase (ROCK) signaling pathway is involved in various cellular functions, including migration, proliferation, and smooth muscle contraction. Here we examined the potential role of this pathway in junctional zone (JZ) contraction in women with and without ADS. We demonstrated that in the normal JZ, RhoA and ROCK-I messenger RNA (mRNA) and protein expression was significantly higher in the proliferative phase of the menstrual cycle than in the secretory phase. Expression of RhoA and ROCK-I in the JZ from women with ADS was significantly higher than in the control women and showed no significant differences across the menstrual cycle. Treatment of JZ smooth muscle cells (JZSMCs) with estrogen at 0, 1, 10, or 100 nmol/L for 24 hours resulted in increased expression of RhoA, ROCK-I, and myosin light-chain (MLC) phosphorylation (p-MLC) in a dose-dependent manner. In parallel to its effects on p-MLC, estrogen-mediated, dose-dependent contraction responses in JZSMCs. Estrogen-mediated contraction in the ADS group was significantly higher than in the controls and also showed no significant differences across the menstrual cycle. These effects were suppressed in the presence of ICI 182780 or Y27632, supporting an estrogen receptor-dependent and RhoA activation-dependent mechanism. Our results indicate that the level of RhoA and ROCK-I increases in patients with ADS and the cyclic change is lost. Estrogen may affect uterine JZ contraction of ADS by enhancing RhoA/ ROCK-I signaling. © The Author(s) 2015.

The rho-exchange isovector parity-violating potential

International Nuclear Information System (INIS)

McKellar, B.H.J.

1979-01-01

It is shown that the rho-exchange isovector parity-violating potential is constrained by PCAC to be much weaker than the π-exchange potential and much weaker than recently proposed by Galic et al (J. Phys. G.; 5: L113 (1979)). This potential does not therefore provide a mechanism for suppressing enhanced neutral-current effects in the π-exchange potential. (author)

Within-Host Variations of Human Papillomavirus Reveal APOBEC-Signature Mutagenesis in the Viral Genome.

Science.gov (United States)

Hirose, Yusuke; Onuki, Mamiko; Tenjimbayashi, Yuri; Mori, Seiichiro; Ishii, Yoshiyuki; Takeuchi, Takamasa; Tasaka, Nobutaka; Satoh, Toyomi; Morisada, Tohru; Iwata, Takashi; Miyamoto, Shingo; Matsumoto, Koji; Sekizawa, Akihiko; Kukimoto, Iwao

2018-03-28

Persistent infection with oncogenic human papillomaviruses (HPVs) causes cervical cancer, accompanied with the accumulation of somatic mutations into the host genome. There are concomitant genetic changes in the HPV genome during viral infection; however, their relevance to cervical carcinogenesis is poorly understood. Here we explored within-host genetic diversity of HPV by performing deep sequencing analyses of viral whole-genome sequences in clinical specimens. The whole genomes of HPV types 16, 52 and 58 were amplified by type-specific PCR from total cellular DNA of cervical exfoliated cells collected from patients with cervical intraepithelial neoplasia (CIN) and invasive cervical cancer (ICC), and were deep-sequenced. After constructing a reference vial genome sequence for each specimen, nucleotide positions showing changes with > 0.5% frequencies compared to the reference sequence were determined for individual samples. In total, 1,052 positions of nucleotide variations were detected in HPV genomes from 151 samples (CIN1, n = 56; CIN2/3, n = 68; ICC, n = 27), with varying numbers per sample. Overall, C-to-T and C-to-A substitutions were the dominant changes observed across all histological grades. While C-to-T transitions were predominantly detected in CIN1, their prevalence was decreased in CIN2/3 and fell below that of C-to-A transversions in ICC. Analysis of the tri-nucleotides context encompassing substituted bases revealed that Tp C pN, a preferred target sequence for cellular APOBEC cytosine deaminases, was a primary site for C-to-T substitutions in the HPV genome. These results strongly imply that the APOBEC proteins are drivers of HPV genome mutation, particularly in CIN1 lesions. IMPORTANCE HPVs exhibit surprisingly high levels of genetic diversity, including a large repertoire of minor genomic variants in each viral genotype. Here, by conducting deep sequencing analyses, we show for the first time a comprehensive snapshot of the "within-host

Stepwise high-throughput virtual screening of Rho kinase inhibitors from natural product library and potential therapeutics for pulmonary hypertension.

Science.gov (United States)

Su, Hao; Yan, Ji; Xu, Jian; Fan, Xi-Zhen; Sun, Xian-Lin; Chen, Kang-Yu

2015-08-01

Pulmonary hypertension (PH) is a devastating disease characterized by progressive elevation of pulmonary arterial pressure and vascular resistance due to pulmonary vasoconstriction and vessel remodeling. The activation of RhoA/Rho-kinase (ROCK) pathway plays a central role in the pathologic progression of PH and thus the Rho kinase, an essential effector of the ROCK pathway, is considered as a potential therapeutic target to attenuate PH. In the current study, a synthetic pipeline is used to discover new potent Rho inhibitors from various natural products. In the pipeline, the stepwise high-throughput virtual screening, quantitative structure-activity relationship (QSAR)-based rescoring, and kinase assay were integrated. The screening was performed against a structurally diverse, drug-like natural product library, from which six identified compounds were tested to determine their inhibitory potencies agonist Rho by using a standard kinase assay protocol. With this scheme, we successfully identified two potent Rho inhibitors, namely phloretin and baicalein, with activity values of IC50 = 0.22 and 0.95 μM, respectively. Structural examination suggested that complicated networks of non-bonded interactions such as hydrogen bonding, hydrophobic forces, and van der Waals contacts across the complex interfaces of Rho kinase are formed with the screened compounds.

Fabrication and non-covalent modification of highly oriented thin films of a zeolite-like metal-organic framework (ZMOF) with rho topology

KAUST Repository

Shekhah, Osama

2015-01-01

Here we report the fabrication of the first thin film of a zeolite-like metal-organic framework (ZMOF) with rho topology (rho-ZMOF-1, ([In48(HImDC)96]48-)n) in a highly oriented fashion on a gold-functionalized substrate. The oriented rho-ZMOF-1 film was functionalized by non-covalent modification via post-synthetic exchange of different probe molecules, such as acridine yellow, methylene blue, and Nile red. In addition, encapsulation of a porphyrin moiety was achieved via in situ synthesis and construction of the rho-ZMOF. Adsorption kinetics of volatile organic compounds on rho-ZMOF-1 thin films was also investigated. This study suggests that rho-ZMOF-1 thin films can be regarded as a promising platform for various applications such as sensing and catalysis. This journal is

Two closely related Rho GTPases, Cdc42 and RacA, of the en-dophytic fungus Epichloë festucae have contrasting roles for ROS production and symbiotic infection synchronized with the host plant.

Science.gov (United States)

Kayano, Yuka; Tanaka, Aiko; Takemoto, Daigo

2018-01-01

Epichloë festucae is an endophytic fungus which systemically colonizes temperate grasses to establish symbiotic associations. Maintaining symptomless infection is a key requirement for endophytes, a feature that distinguishes them from pathogenic fungi. While pathogenic fungi extend their hyphae by tip growth, hyphae of E. festucae systemically colonize the intercellular space of expanding host leaves via a unique mechanism of hyphal intercalary growth. This study reports that two homologous Rho GTPases, Cdc42 and RacA, have distinctive roles in the regulation of E. festucae growth in planta. Here we highlight the vital role of Cdc42 for intercalary hyphal growth, as well as involvement of RacA in regulation of hyphal network formation, and demonstrate the consequences of mutations in these genes on plant tissue infection. Functions of Cdc42 and RacA are mediated via interactions with BemA and NoxR respectively, which are expected components of the ROS producing NOX complex. Symbiotic defects found in the racA mutant were rescued by introduction of a Cdc42 with key amino acids substitutions crucial for RacA function, highlighting the significance of the specific interactions of these GTPases with BemA and NoxR for their functional differentiation in symbiotic infection.

Cell cycle-dependent Rho GTPase activity dynamically regulates cancer cell motility and invasion in vivo.

Science.gov (United States)

Kagawa, Yoshinori; Matsumoto, Shinji; Kamioka, Yuji; Mimori, Koshi; Naito, Yoko; Ishii, Taeko; Okuzaki, Daisuke; Nishida, Naohiro; Maeda, Sakae; Naito, Atsushi; Kikuta, Junichi; Nishikawa, Keizo; Nishimura, Junichi; Haraguchi, Naotsugu; Takemasa, Ichiro; Mizushima, Tsunekazu; Ikeda, Masataka; Yamamoto, Hirofumi; Sekimoto, Mitsugu; Ishii, Hideshi; Doki, Yuichiro; Matsuda, Michiyuki; Kikuchi, Akira; Mori, Masaki; Ishii, Masaru

2013-01-01

The mechanism behind the spatiotemporal control of cancer cell dynamics and its possible association with cell proliferation has not been well established. By exploiting the intravital imaging technique, we found that cancer cell motility and invasive properties were closely associated with the cell cycle. In vivo inoculation of human colon cancer cells bearing fluorescence ubiquitination-based cell cycle indicator (Fucci) demonstrated an unexpected phenomenon: S/G2/M cells were more motile and invasive than G1 cells. Microarray analyses showed that Arhgap11a, an uncharacterized Rho GTPase-activating protein (RhoGAP), was expressed in a cell-cycle-dependent fashion. Expression of ARHGAP11A in cancer cells suppressed RhoA-dependent mechanisms, such as stress fiber formation and focal adhesion, which made the cells more prone to migrate. We also demonstrated that RhoA suppression by ARHGAP11A induced augmentation of relative Rac1 activity, leading to an increase in the invasive properties. RNAi-based inhibition of Arhgap11a reduced the invasion and in vivo expansion of cancers. Additionally, analysis of human specimens showed the significant up-regulation of Arhgap11a in colon cancers, which was correlated with clinical invasion status. The present study suggests that ARHGAP11A, a cell cycle-dependent RhoGAP, is a critical regulator of cancer cell mobility and is thus a promising therapeutic target in invasive cancers.

Cell cycle-dependent Rho GTPase activity dynamically regulates cancer cell motility and invasion in vivo.

Directory of Open Access Journals (Sweden)

Yoshinori Kagawa

Full Text Available The mechanism behind the spatiotemporal control of cancer cell dynamics and its possible association with cell proliferation has not been well established. By exploiting the intravital imaging technique, we found that cancer cell motility and invasive properties were closely associated with the cell cycle. In vivo inoculation of human colon cancer cells bearing fluorescence ubiquitination-based cell cycle indicator (Fucci demonstrated an unexpected phenomenon: S/G2/M cells were more motile and invasive than G1 cells. Microarray analyses showed that Arhgap11a, an uncharacterized Rho GTPase-activating protein (RhoGAP, was expressed in a cell-cycle-dependent fashion. Expression of ARHGAP11A in cancer cells suppressed RhoA-dependent mechanisms, such as stress fiber formation and focal adhesion, which made the cells more prone to migrate. We also demonstrated that RhoA suppression by ARHGAP11A induced augmentation of relative Rac1 activity, leading to an increase in the invasive properties. RNAi-based inhibition of Arhgap11a reduced the invasion and in vivo expansion of cancers. Additionally, analysis of human specimens showed the significant up-regulation of Arhgap11a in colon cancers, which was correlated with clinical invasion status. The present study suggests that ARHGAP11A, a cell cycle-dependent RhoGAP, is a critical regulator of cancer cell mobility and is thus a promising therapeutic target in invasive cancers.

Non-host Plant Resistance against Phytophthora capsici Is Mediated in Part by Members of the I2 R Gene Family in Nicotiana spp.

Science.gov (United States)

Vega-Arreguín, Julio C; Shimada-Beltrán, Harumi; Sevillano-Serrano, Jacobo; Moffett, Peter

2017-01-01

The identification of host genes associated with resistance to Phytophthora capsici is crucial to developing strategies of control against this oomycete pathogen. Since there are few sources of resistance to P. capsici in crop plants, non-host plants represent a promising source of resistance genes as well as excellent models to study P. capsici - plant interactions. We have previously shown that non-host resistance to P. capsici in Nicotiana spp. is mediated by the recognition of a specific P. capsici effector protein, PcAvr3a1 in a manner that suggests the involvement of a cognate disease resistance (R) genes. Here, we have used virus-induced gene silencing (VIGS) and transgenic tobacco plants expressing dsRNA in Nicotiana spp. to identify candidate R genes that mediate non-host resistance to P. capsici . Silencing of members of the I2 multigene family in the partially resistant plant N. edwardsonii and in the resistant N. tabacum resulted in compromised resistance to P. capsici . VIGS of two other components required for R gene-mediated resistance, EDS1 and SGT1 , also enhanced susceptibility to P. capsici in N. edwardsonii , as well as in the susceptible plants N. benthamiana and N. clevelandii . The silencing of I2 family members in N. tabacum also compromised the recognition of PcAvr3a1. These results indicate that in this case, non-host resistance is mediated by the same components normally associated with race-specific resistance.

Relative Proper Motions in the Rho Ophiuchi Cluster

Science.gov (United States)

2016-01-06

identified as YSOs and may be newly identified cluster members. Key words: ISM: individual objects (Rho Ophiuchi cloud) – stars: formation – stars: pre-main...sequence 1. INTRODUCTION The majority of stars in the Galaxy form in clusters that once the binding mass of the molecular gas is removed, disperse into

HAWC+/SOFIA observations of Rho Oph A: far-infrared polarization spectrum

Science.gov (United States)

Santos, Fabio; Dowell, Charles D.; Houde, Martin; Looney, Leslie; Lopez-Rodriguez, Enrique; Novak, Giles; Ward-Thompson, Derek; HAWC+ Science Team

2018-01-01

In this work, we present preliminary results from the HAWC+ far-infrared polarimeter that operates on the SOFIA airborne observatory. The densest portions of the Rho Ophiuchi molecular complex, known as Rho Oph A, have been mapped using HAWC+ bands C (89 microns) and D (155 microns). Rho Oph A is a well known nearby star forming region. At the target's distance of approximately 130 pc, our observations provide excellent spatial resolution (~5 mpc in band C).The magnetic field map suggests a compressed and distorted field morphology around Oph S1, a massive B3 star that is the main heat source of Rho Oph A. We compute the ratio p(D)/p(C), where p(C) and p(D) are the polarization degree maps at bands C and D, respectively. This ratio estimates the slope of the polarization spectrum in the far-infrared. Although the slope is predicted to be positive by dust grain models, previous observations of other molecular clouds have revealed that negative slopes are common. In Rho Oph A, we find that there is a smooth gradient of p(D)/p(C) across the mapped field. The change in p(D)/p(C) is well correlated with the integrated NH3 (1,1) emission. A positive slope dominates the lower density and well illuminated portions of the cloud, whereas a transition to a negative slope is observed at the denser and less evenly illuminated cloud core.We interpret the positive to negative slope transition as being consistent with the radiative torques (RATs) grain alignment theory. For the sight lines of higher column density, polarized emission from the warmer outer cloud layers is added to emission from the colder inner well-shielded layers lying along the same line-of-sight. Given that the outer layers receive more radiation from Oph S1, their grain alignment efficiency is expected to be higher according to RATs. The combination of warmer, well aligned grains with cooler, poorly aligned grains is what causes the negative slope. This effect is not present in the sight lines of lower column

Maturation and integration of adult born hippocampal neurons: signal convergence onto small Rho GTPases

Directory of Open Access Journals (Sweden)

Krishna eVadodaria

2013-08-01

Full Text Available Adult neurogenesis, restricted to specific regions in the mammalian brain, represents one of the most interesting forms of plasticity in the mature nervous system. Adult-born hippocampal neurons play important roles in certain forms of learning and memory, and altered hippocampal neurogenesis has been associated with a number of neuropsychiatric diseases such as major depression and epilepsy. Newborn neurons go through distinct developmental steps from a dividing neurogenic precursor to a synaptically integrated mature neuron. Previous studies have uncovered several molecular signaling pathways involved in distinct steps of this maturational process. In this context, the small Rho GTPases, Cdc42, Rac1 and RhoA have recently been shown to regulate the morphological and synaptic maturation of adult-born dentate granule cells in vivo. Distinct upstream regulators, including several growth factors that modulate maturation and integration of newborn neurons have been shown to also recruit the small Rho GTPases. Here we review recent findings and highlight the possibility that small Rho GTPases may act as central assimilators, downstream of critical input onto adult-born hippocampal neurons contributing to their maturation and integration into the existing dentate gyrus circuitry.

Understanding specificity in metabolic pathways-Structural biology of human nucleotide metabolism

International Nuclear Information System (INIS)

Welin, Martin; Nordlund, Paer

2010-01-01

Interactions are the foundation of life at the molecular level. In the plethora of activities in the cell, the evolution of enzyme specificity requires the balancing of appropriate substrate affinity with a negative selection, in order to minimize interactions with other potential substrates in the cell. To understand the structural basis for enzyme specificity, the comparison of structural and biochemical data between enzymes within pathways using similar substrates and effectors is valuable. Nucleotide metabolism is one of the largest metabolic pathways in the human cell and is of outstanding therapeutic importance since it activates and catabolises nucleoside based anti-proliferative drugs and serves as a direct target for anti-proliferative drugs. In recent years the structural coverage of the enzymes involved in human nucleotide metabolism has been dramatically improved and is approaching completion. An important factor has been the contribution from the Structural Genomics Consortium (SGC) at Karolinska Institutet, which recently has solved 33 novel structures of enzymes and enzyme domains in human nucleotide metabolism pathways and homologs thereof. In this review we will discuss some of the principles for substrate specificity of enzymes in human nucleotide metabolism illustrated by a selected set of enzyme families where a detailed understanding of the structural determinants for specificity is now emerging.

Analysis of host microRNA function uncovers a role for miR-29b-2-5p in Shigella capture by filopodia.

Science.gov (United States)

Sunkavalli, Ushasree; Aguilar, Carmen; Silva, Ricardo Jorge; Sharan, Malvika; Cruz, Ana Rita; Tawk, Caroline; Maudet, Claire; Mano, Miguel; Eulalio, Ana

2017-04-01

MicroRNAs play an important role in the interplay between bacterial pathogens and host cells, participating as host defense mechanisms, as well as exploited by bacteria to subvert host cellular functions. Here, we show that microRNAs modulate infection by Shigella flexneri, a major causative agent of bacillary dysentery in humans. Specifically, we characterize the dual regulatory role of miR-29b-2-5p during infection, showing that this microRNA strongly favors Shigella infection by promoting both bacterial binding to host cells and intracellular replication. Using a combination of transcriptome analysis and targeted high-content RNAi screening, we identify UNC5C as a direct target of miR-29b-2-5p and show its pivotal role in the modulation of Shigella binding to host cells. MiR-29b-2-5p, through repression of UNC5C, strongly enhances filopodia formation thus increasing Shigella capture and promoting bacterial invasion. The increase of filopodia formation mediated by miR-29b-2-5p is dependent on RhoF and Cdc42 Rho-GTPases. Interestingly, the levels of miR-29b-2-5p, but not of other mature microRNAs from the same precursor, are decreased upon Shigella replication at late times post-infection, through degradation of the mature microRNA by the exonuclease PNPT1. While the relatively high basal levels of miR-29b-2-5p at the start of infection ensure efficient Shigella capture by host cell filopodia, dampening of miR-29b-2-5p levels later during infection may constitute a bacterial strategy to favor a balanced intracellular replication to avoid premature cell death and favor dissemination to neighboring cells, or alternatively, part of the host response to counteract Shigella infection. Overall, these findings reveal a previously unappreciated role of microRNAs, and in particular miR-29b-2-5p, in the interaction of Shigella with host cells.

Analysis of host microRNA function uncovers a role for miR-29b-2-5p in Shigella capture by filopodia.

Directory of Open Access Journals (Sweden)

Ushasree Sunkavalli

2017-04-01

Full Text Available MicroRNAs play an important role in the interplay between bacterial pathogens and host cells, participating as host defense mechanisms, as well as exploited by bacteria to subvert host cellular functions. Here, we show that microRNAs modulate infection by Shigella flexneri, a major causative agent of bacillary dysentery in humans. Specifically, we characterize the dual regulatory role of miR-29b-2-5p during infection, showing that this microRNA strongly favors Shigella infection by promoting both bacterial binding to host cells and intracellular replication. Using a combination of transcriptome analysis and targeted high-content RNAi screening, we identify UNC5C as a direct target of miR-29b-2-5p and show its pivotal role in the modulation of Shigella binding to host cells. MiR-29b-2-5p, through repression of UNC5C, strongly enhances filopodia formation thus increasing Shigella capture and promoting bacterial invasion. The increase of filopodia formation mediated by miR-29b-2-5p is dependent on RhoF and Cdc42 Rho-GTPases. Interestingly, the levels of miR-29b-2-5p, but not of other mature microRNAs from the same precursor, are decreased upon Shigella replication at late times post-infection, through degradation of the mature microRNA by the exonuclease PNPT1. While the relatively high basal levels of miR-29b-2-5p at the start of infection ensure efficient Shigella capture by host cell filopodia, dampening of miR-29b-2-5p levels later during infection may constitute a bacterial strategy to favor a balanced intracellular replication to avoid premature cell death and favor dissemination to neighboring cells, or alternatively, part of the host response to counteract Shigella infection. Overall, these findings reveal a previously unappreciated role of microRNAs, and in particular miR-29b-2-5p, in the interaction of Shigella with host cells.

Double-spin asymmetries in the cross section of rho sup 0 and phi production at intermediate energies

CERN Document Server

Airapetian, A; Akopov, Z; Amarian, M

2003-01-01

Double-spin asymmetries in the cross section of electroproduction of rho sup 0 and phi mesons on the proton and deuteron are measured at the HERMES experiment. The photoabsorption asymmetry in exclusive rho sup 0 electroproduction on the proton exhibits a positive tendency. This is consistent with theoretical predictions that the exchange of an object with unnatural parity contributes to exclusive rho sup 0 electroproduction by transverse photons. The photoabsorption asymmetry on the deuteron is found to be consistent with zero. Double-spin asymmetries in rho sup 0 and phi meson electroproduction by quasi-real photons were also found to be consistent with zero; the asymmetry in the case of the phi meson is compatible with a theoretical prediction which involves s anti s knockout from the nucleon. (orig.)

Salmonella Typhimurium-specific bacteriophage ΦSH19 and the origins of species specificity in the Vi01-like phage family

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Wilson Ray

2011-11-01

Full Text Available Abstract Background Whole genome sequencing of bacteriophages suitable for biocontrol of pathogens in food products is a pre-requisite to any phage-based intervention procedure. Trials involving the biosanitization of Salmonella Typhimurium in the pig production environment identified one such candidate, ΦSH19. Results This phage was sequenced and analysis of its 157,785 bp circular dsDNA genome revealed a number of interesting features. ΦSH19 constitutes another member of the recently-proposed Myoviridae Vi01-like family of phages, containing S. Typhi-specific Vi01 and Shigella-specific SboM-AG3. At the nucleotide level ΦSH19 is highly similar to phage Vi01 (80-98% pairwise identity over the length of the genome, with the major differences lying in the region associated with host-range determination. Analyses of the proteins encoded within this region by ΦSH19 revealed a cluster of three putative tail spikes. Of the three tail spikes, two have protein domains associated with the pectate lyase family of proteins (Tsp2 and P22 tail spike family (Tsp3 with the prospect that these enable Salmonella O antigen degradation. Tail spike proteins of Vi01 and SboM-AG3 are predicted to contain conserved right-handed parallel β-helical structures but the internal protein domains are varied allowing different host specificities. Conclusions The addition or exchange of tail spike protein modules is a major contributor to host range determination in the Vi01-like phage family.

Seneca Valley Virus Suppresses Host Type I Interferon Production by Targeting Adaptor Proteins MAVS, TRIF, and TANK for Cleavage.

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Qian, Suhong; Fan, Wenchun; Liu, Tingting; Wu, Mengge; Zhang, Huawei; Cui, Xiaofang; Zhou, Yun; Hu, Junjie; Wei, Shaozhong; Chen, Huanchun; Li, Xiangmin; Qian, Ping

2017-08-15

Seneca Valley virus (SVV) is an oncolytic RNA virus belonging to the Picornaviridae family. Its nucleotide sequence is highly similar to those of members of the Cardiovirus genus. SVV is also a neuroendocrine cancer-selective oncolytic picornavirus that can be used for anticancer therapy. However, the interaction between SVV and its host is yet to be fully characterized. In this study, SVV inhibited antiviral type I interferon (IFN) responses by targeting different host adaptors, including mitochondrial antiviral signaling (MAVS), Toll/interleukin 1 (IL-1) receptor domain-containing adaptor inducing IFN-β (TRIF), and TRAF family member-associated NF-κB activator (TANK), via viral 3C protease (3C pro ). SVV 3C pro mediated the cleavage of MAVS, TRIF, and TANK at specific sites, which required its protease activity. The cleaved MAVS, TRIF, and TANK lost the ability to regulate pattern recognition receptor (PRR)-mediated IFN production. The cleavage of TANK also facilitated TRAF6-induced NF-κB activation. SVV was also found to be sensitive to IFN-β. Therefore, SVV suppressed antiviral IFN production to escape host antiviral innate immune responses by cleaving host adaptor molecules. IMPORTANCE Host cells have developed various defenses against microbial pathogen infection. The production of IFN is the first line of defense against microbial infection. However, viruses have evolved many strategies to disrupt this host defense. SVV, a member of the Picornavirus genus, is an oncolytic virus that shows potential functions in anticancer therapy. It has been demonstrated that IFN can be used in anticancer therapy for certain tumors. However, the relationship between oncolytic virus and innate immune response in anticancer therapy is still not well known. In this study, we showed that SVV has evolved as an effective mechanism to inhibit host type I IFN production by using its 3C pro to cleave the molecules MAVS, TRIF, and TANK directly. These molecules are crucial for

Structure directing agents induced morphology evolution and phase transition from indium-based rho- to sod-ZMOF

KAUST Repository

Shi, Yanshu; Cairns, Amy; Liu, Yunling; Belmabkhout, Youssef; Cai, Xuechao; Pang, Maolin; Eddaoudi, Mohamed

2017-01-01

In this report, indium-based rho-and sod-ZMOFs with different morphologies and sizes were prepared. Simultaneous morphology evolution and phase transformation from porous rho-to nonporous sod-ZMOFs were reported for the first time by simply varying the concentration of structure directing agents (SDAs).

Structure directing agents induced morphology evolution and phase transition from indium-based rho- to sod-ZMOF

KAUST Repository

Shi, Yanshu

2017-06-23

In this report, indium-based rho-and sod-ZMOFs with different morphologies and sizes were prepared. Simultaneous morphology evolution and phase transformation from porous rho-to nonporous sod-ZMOFs were reported for the first time by simply varying the concentration of structure directing agents (SDAs).

MicroRNAs from the parasitic plant Cuscuta campestris target host messenger RNAs.

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Shahid, Saima; Kim, Gunjune; Johnson, Nathan R; Wafula, Eric; Wang, Feng; Coruh, Ceyda; Bernal-Galeano, Vivian; Phifer, Tamia; dePamphilis, Claude W; Westwood, James H; Axtell, Michael J

2018-01-03

Dodders (Cuscuta spp.) are obligate parasitic plants that obtain water and nutrients from the stems of host plants via specialized feeding structures called haustoria. Dodder haustoria facilitate bidirectional movement of viruses, proteins and mRNAs between host and parasite, but the functional effects of these movements are not known. Here we show that Cuscuta campestris haustoria accumulate high levels of many novel microRNAs (miRNAs) while parasitizing Arabidopsis thaliana. Many of these miRNAs are 22 nucleotides in length. Plant miRNAs of this length are uncommon, and are associated with amplification of target silencing through secondary short interfering RNA (siRNA) production. Several A. thaliana mRNAs are targeted by 22-nucleotide C. campestris miRNAs during parasitism, resulting in mRNA cleavage, secondary siRNA production, and decreased mRNA accumulation. Hosts with mutations in two of the loci that encode target mRNAs supported significantly higher growth of C. campestris. The same miRNAs that are expressed and active when C. campestris parasitizes A. thaliana are also expressed and active when it infects Nicotiana benthamiana. Homologues of target mRNAs from many other plant species also contain the predicted target sites for the induced C. campestris miRNAs. These data show that C. campestris miRNAs act as trans-species regulators of host-gene expression, and suggest that they may act as virulence factors during parasitism.

The Rho Kinases: Critical Mediators of Multiple Profibrotic Processes and Rational Targets for New Therapies for Pulmonary Fibrosis

Science.gov (United States)

Knipe, Rachel S.; Tager, Andrew M.

2015-01-01

Idiopathic pulmonary fibrosis (IPF) is characterized by progressive lung scarring, short median survival, and limited therapeutic options, creating great need for new pharmacologic therapies. IPF is thought to result from repetitive environmental injury to the lung epithelium, in the context of aberrant host wound healing responses. Tissue responses to injury fundamentally involve reorganization of the actin cytoskeleton of participating cells, including epithelial cells, fibroblasts, endothelial cells, and macrophages. Actin filament assembly and actomyosin contraction are directed by the Rho-associated coiled-coil forming protein kinase (ROCK) family of serine/threonine kinases (ROCK1 and ROCK2). As would therefore be expected, lung ROCK activation has been demonstrated in humans with IPF and in animal models of this disease. ROCK inhibitors can prevent fibrosis in these models, and more importantly, induce the regression of already established fibrosis. Here we review ROCK structure and function, upstream activators and downstream targets of ROCKs in pulmonary fibrosis, contributions of ROCKs to profibrotic cellular responses to lung injury, ROCK inhibitors and their efficacy in animal models of pulmonary fibrosis, and potential toxicities of ROCK inhibitors in humans, as well as involvement of ROCKs in fibrosis in other organs. As we discuss, ROCK activation is required for multiple profibrotic responses, in the lung and multiple other organs, suggesting ROCK participation in fundamental pathways that contribute to the pathogenesis of a broad array of fibrotic diseases. Multiple lines of evidence therefore indicate that ROCK inhibition has great potential to be a powerful therapeutic tool in the treatment of fibrosis, both in the lung and beyond. PMID:25395505

NU-IN: Nucleotide evolution and input module for the EvolSimulator genome simulation platform

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Barker Michael S

2010-08-01

Full Text Available Abstract Background There is increasing demand to test hypotheses that contrast the evolution of genes and gene families among genomes, using simulations that work across these levels of organization. The EvolSimulator program was developed recently to provide a highly flexible platform for forward simulations of amino acid evolution in multiple related lineages of haploid genomes, permitting copy number variation and lateral gene transfer. Synonymous nucleotide evolution is not currently supported, however, and would be highly advantageous for comparisons to full genome, transcriptome, and single nucleotide polymorphism (SNP datasets. In addition, EvolSimulator creates new genomes for each simulation, and does not allow the input of user-specified sequences and gene family information, limiting the incorporation of further biological realism and/or user manipulations of the data. Findings We present modified C++ source code for the EvolSimulator platform, which we provide as the extension module NU-IN. With NU-IN, synonymous and non-synonymous nucleotide evolution is fully implemented, and the user has the ability to use real or previously-simulated sequence data to initiate a simulation of one or more lineages. Gene family membership can be optionally specified, as well as gene retention probabilities that model biased gene retention. We provide PERL scripts to assist the user in deriving this information from previous simulations. We demonstrate the features of NU-IN by simulating genome duplication (polyploidy in the presence of ongoing copy number variation in an evolving lineage. This example is initiated with real genomic data, and produces output that we analyse directly with existing bioinformatic pipelines. Conclusions The NU-IN extension module is a publicly available open source software (GNU GPLv3 license extension to EvolSimulator. With the NU-IN module, users are now able to simulate both drift and selection at the nucleotide

Genetic diversity and distribution patterns of host insects of Caterpillar Fungus Ophiocordyceps sinensis in the Qinghai-Tibet Plateau.

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Qing-Mei Quan

Full Text Available The caterpillar fungus Ophiocordyceps sinensis is one of the most valuable medicinal fungi in the world, and it requires host insects in family Hepialidae (Lepidoptera to complete its life cycle. However, the genetic diversity and phylogeographic structures of the host insects remain to be explored. We analyzed the genetic diversity and temporal and spatial distribution patterns of genetic variation of the host insects throughout the O. sinensis distribution. Abundant haplotype and nucleotide diversity mainly existed in the areas of Nyingchi, ShangriLa, and around the edge of the Qinghai-Tibet Plateau, where are considered as the diversity center or micro-refuges of the host insects of O. sinensis. However, there was little genetic variation among host insects from 72.1% of all populations, indicating that the host species composition might be relatively simple in large-scale O. sinensis populations. All host insects are monophyletic except for those from four O. sinensis populations around Qinghai Lake. Significant phylogeographic structure (NST>GST, P<0.05 was revealed for the monophyletic host insects, and the three major phylogenetic groups corresponded with specific geographical areas. The divergence of most host insects was estimated to have occurred at ca. 3.7 Ma, shortly before the rapid uplift of the QTP. The geographical distribution and star-like network of the haplotypes implied that most host insects were derived from the relicts of a once-widespread host that subsequently became fragmented. Neutrality tests, mismatch distribution analysis, and expansion time estimation confirmed that most host insects presented recent demographic expansions that began ca. 0.118 Ma in the late Pleistocene. Therefore, the genetic diversity and distribution of the present-day insects should be attributed to effects of the Qinghai-Tibet Plateau uplift and glacial advance/retreat cycles during the Quaternary ice age. These results provide valuable

Measurements of Branching Ratios And Search for CP Violation in the Modes B0 to Rho Pi, Rho K

Energy Technology Data Exchange (ETDEWEB)

Laplace, Sandrine; /Paris U., VI-VII

2006-09-18

The BABAR experiment, at the PEP-II collider at SLAC, has been studying since 1999 CP violation in the B meson system. After the precise measurement of sin2{beta}, one is now concentrating on measuring the angles {alpha} and {gamma} of the unitarity triangle. The work presented in this thesis concerns the measurement of the angle {alpha} in the B{sup 0} {yields} {rho}{pi} mode.

Methanol conversion to lower olefins over RHO type zeolite

KAUST Repository

Masih, Dilshad; Imai, Hiroyuki; Yokoi, Toshiyuki; Kondo, Junkonomura; Tatsumi, Takashi

2013-01-01

Eight-membered ring small-pore zeolite of RHO-type topology has been synthesized, characterized and tested for methanol-to-olefin (MTO) reaction. The zeolite was hydrothermally crystallized from the gel with Si/Al ratio of 5.0. It showed a high BET

Role of contractile prostaglandins and Rho-kinase in growth factor-induced airway smooth muscle contraction

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Zaagsma Johan

2005-07-01

Full Text Available Abstract Background In addition to their proliferative and differentiating effects, several growth factors are capable of inducing a sustained airway smooth muscle (ASM contraction. These contractile effects were previously found to be dependent on Rho-kinase and have also been associated with the production of eicosanoids. However, the precise mechanisms underlying growth factor-induced contraction are still unknown. In this study we investigated the role of contractile prostaglandins and Rho-kinase in growth factor-induced ASM contraction. Methods Growth factor-induced contractions of guinea pig open-ring tracheal preparations were studied by isometric tension measurements. The contribution of Rho-kinase, mitogen-activated protein kinase (MAPK and cyclooxygenase (COX to these reponses was established, using the inhibitors Y-27632 (1 μM, U-0126 (3 μM and indomethacin (3 μM, respectively. The Rho-kinase dependency of contractions induced by exogenously applied prostaglandin F2α (PGF2α and prostaglandin E2 (PGE2 was also studied. In addition, the effects of the selective FP-receptor antagonist AL-8810 (10 μM and the selective EP1-antagonist AH-6809 (10 μM on growth factor-induced contractions were investigated, both in intact and epithelium-denuded preparations. Growth factor-induced PGF2α-and PGE2-release in the absence and presence of Y-27632, U-0126 and indomethacin, was assessed by an ELISA-assay. Results Epidermal growth factor (EGF-and platelet-derived growth factor (PDGF-induced contractions of guinea pig tracheal smooth muscle preparations were dependent on Rho-kinase, MAPK and COX. Interestingly, growth factor-induced PGF2α-and PGE2-release from tracheal rings was significantly reduced by U-0126 and indomethacin, but not by Y-27632. Also, PGF2α-and PGE2-induced ASM contractions were largely dependent on Rho-kinase, in contrast to other contractile agonists like histamine. The FP-receptor antagonist AL-8810 (10 μM significantly

T^{\\sigma}_{\\rho}(G) Theories and Their Hilbert Series

CERN Document Server

Cremonesi, Stefano; Mekareeya, Noppadol; Zaffaroni, Alberto

2015-01-01

We give an explicit formula for the Higgs and Coulomb branch Hilbert series for the class of 3d N=4 superconformal gauge theories T^{\\sigma}_{\\rho}(G) corresponding to a set of D3 branes ending on NS5 and D5-branes, with or without O3 planes. Here G is a classical group, \\sigma is a partition of G and \\rho a partition of the dual group G^\\vee. In deriving such a formula we make use of the recently discovered formula for the Hilbert series of the quantum Coulomb branch of N=4 superconformal theories. The result can be expressed in terms of a generalization of a class of symmetric functions, the Hall-Littlewood polynomials, and can be interpreted in mathematical language in terms of localization. We mainly consider the case G=SU(N) but some interesting results are also given for orthogonal and symplectic groups.

Involvement of Rho kinase in the pathogenesis of acute pulmonary embolism-induced polystyrene microspheres in rats.

Science.gov (United States)

Toba, M; Nagaoka, T; Morio, Y; Sato, K; Uchida, K; Homma, N; Takahashi, K

2010-03-01

Acute pulmonary embolism (PE) is a life-threatening disease, and several vasoconstrictors, including endothelin-1 (ET-1), play a key role in vasoconstriction and hypoxemia during the development of PE. Rho kinase is activated by various vasoconstrictors resulting in vascular contraction and remodeling. Recent evidence has revealed an important role of Rho kinase in the pathogenesis of systemic and pulmonary vascular diseases. However, contribution of Rho kinase in PE remains unclear. We thus investigated the role of Rho kinase in the PE rat model induced by intrajugular administration of polystyrene microspheres (mean diameter, 26 microm). At 6 h following the administration of microspheres (1.5 ml/kg), right ventricular systolic pressure (RVSP) was higher in the PE than in the control rats (15.8 +/- 1.6 vs. 32.9 +/- 7.5 mmHg). Arterial oxygen tension was lower (92.3 +/- 12.5 vs. 66.0 +/- 17.7 Torr), and alveolar-arterial difference in oxygen partial pressure was higher (3.9 +/- 3.8 vs. 36.5 +/- 26.9 Torr) in the PE rats. Western blotting analysis revealed upregulation and downregulation in expression of vascular cell adhesion molecule-1 and endothelial nitric oxide synthase in lungs from the PE rats, respectively, and radioimmunoassay demonstrated an increase in plasma ET-1 levels. Lung Rho kinase alpha expression was greater in the PE rats. At 5 h following administration of microspheres (0.75 ml/kg), intravenous Rho kinase inhibitors HA1077 and Y27632 (3 mg/kg each) attenuated elevation of RVSP (22.0 +/- 3.7, 17.1 +/- 3.2, 14.3 +/- 2.6 mmHg, PE, PE+HA1077, PE+Y27632) and the severity of hypoxemia (66.3 +/- 16.2, 94.9 +/- 23.0, 89.1 +/- 8.5 Torr, PE, PE+HA1077, PE+Y27632) in the PE rats. These results suggest that pulmonary endothelial dysfunction and activation of Rho kinase may contribute to the potentiation of vasoconstriction and hypoxemia in the PE rats.

Complete nucleotide sequence of Alfalfa mosaic virus isolated from alfalfa (Medicago sativa L.) in Argentina.

Science.gov (United States)

Trucco, Verónica; de Breuil, Soledad; Bejerman, Nicolás; Lenardon, Sergio; Giolitti, Fabián

2014-06-01

The complete nucleotide sequence of an Alfalfa mosaic virus (AMV) isolate infecting alfalfa (Medicago sativa L.) in Argentina, AMV-Arg, was determined. The virus genome has the typical organization described for AMV, and comprises 3,643, 2,593, and 2,038 nucleotides for RNA1, 2 and 3, respectively. The whole genome sequence and each encoding region were compared with those of other four isolates that have been completely sequenced from China, Italy, Spain and USA. The nucleotide identity percentages ranged from 95.9 to 99.1 % for the three RNAs and from 93.7 to 99 % for the protein 1 (P1), protein 2 (P2), movement protein and coat protein (CP) encoding regions, whereas the amino acid identity percentages of these proteins ranged from 93.4 to 99.5 %, the lowest value corresponding to P2. CP sequences of AMV-Arg were compared with those of other 25 available isolates, and the phylogenetic analysis based on the CP gene was carried out. The highest percentage of nucleotide sequence identity of the CP gene was 98.3 % with a Chinese isolate and 98.6 % at the amino acid level with four isolates, two from Italy, one from Brazil and the remaining one from China. The phylogenetic analysis showed that AMV-Arg is closely related to subgroup I of AMV isolates. To our knowledge, this is the first report of a complete nucleotide sequence of AMV from South America and the first worldwide report of complete nucleotide sequence of AMV isolated from alfalfa as natural host.

Rho0 production and possible modification in Au+Au and p+p collisions at square root [sNN] = 200 GeV.

Science.gov (United States)

Adams, J; Adler, C; Aggarwal, M M; Ahammed, Z; Amonett, J; Anderson, B D; Arkhipkin, D; Averichev, G S; Badyal, S K; Balewski, J; Barannikova, O; Barnby, L S; Baudot, J; Bekele, S; Belaga, V V; Bellwied, R; Berger, J; Bezverkhny, B I; Bhardwaj, S; Bhati, A K; Bichsel, H; Billmeier, A; Bland, L C; Blyth, C O; Bonner, B E; Botje, M; Boucham, A; Brandin, A; Bravar, A; Cadman, R V; Cai, X Z; Caines, H; Calderón de la Barca Sánchez, M; Carroll, J; Castillo, J; Cebra, D; Chaloupka, P; Chattopadhyay, S; Chen, H F; Chen, Y; Chernenko, S P; Cherney, M; Chikanian, A; Christie, W; Coffin, J P; Cormier, T M; Cramer, J G; Crawford, H J; Das, D; Das, S; Derevschikov, A A; Didenko, L; Dietel, T; Dong, W J; Dong, X; Draper, J E; Du, F; Dubey, A K; Dunin, V B; Dunlop, J C; Dutta Majumdar, M R; Eckardt, V; Efimov, L G; Emelianov, V; Engelage, J; Eppley, G; Erazmus, B; Estienne, M; Fachini, P; Faine, V; Faivre, J; Fatemi, R; Filimonov, K; Filip, P; Finch, E; Fisyak, Y; Flierl, D; Foley, K J; Fu, J; Gagliardi, C A; Gagunashvili, N; Gans, J; Ganti, M S; Gaudichet, L; Geurts, F; Ghazikhanian, V; Ghosh, P; Gonzalez, J E; Grachov, O; Grebenyuk, O; Gronstal, S; Grosnick, D; Guertin, S M; Gupta, A; Gutierrez, T D; Hallman, T J; Hamed, A; Hardtke, D; Harris, J W; Heinz, M; Henry, T W; Heppelmann, S; Hippolyte, B; Hirsch, A; Hjort, E; Hoffmann, G W; Horsley, M; Huang, H Z; Huang, S L; Hughes, E; Humanic, T J; Igo, G; Ishihara, A; Jacobs, P; Jacobs, W W; Janik, M; Jiang, H; Johnson, I; Jones, P G; Judd, E G; Kabana, S; Kaplan, M; Keane, D; Khodyrev, V Yu; Kiryluk, J; Kisiel, A; Klay, J; Klein, S R; Klyachko, A; Koetke, D D; Kollegger, T; Kopytine, M; Kotchenda, L; Kovalenko, A D; Kramer, M; Kravtsov, P; Kravtsov, V I; Krueger, K; Kuhn, C; Kulikov, A I; Kumar, A; Kunde, G J; Kunz, C L; Kutuev, R Kh; Kuznetsov, A A; Lamont, M A C; Landgraf, J M; Lange, S; Lasiuk, B; Laue, F; Lauret, J; Lebedev, A; Lednický, R; LeVine, M J; Li, C; Li, Q; Lindenbaum, S J; Lisa, M A; Liu, F; Liu, L; Liu, Z; Liu, Q J; Ljubicic, T; Llope, W J; Long, H; Longacre, R S; Lopez-Noriega, M; Love, W A; Ludlam, T; Lynn, D; Ma, J; Ma, Y G; Magestro, D; Mahajan, S; Mangotra, L K; Mahapatra, D P; Majka, R; Manweiler, R; Margetis, S; Markert, C; Martin, L; Marx, J; Matis, H S; Matulenko, Yu A; McClain, C J; McShane, T S; Meissner, F; Melnick, Yu; Meschanin, A; Miller, M L; Milosevich, Z; Minaev, N G; Mironov, C; Mischke, A; Mishra, D; Mitchell, J; Mohanty, B; Molnar, L; Moore, C F; Mora-Corral, M J; Morozov, D A; Morozov, V; De Moura, M M; Munhoz, M G; Nandi, B K; Nayak, S K; Nayak, T K; Nelson, J M; Netrakanti, P K; Nikitin, V A; Nogach, L V; Norman, B; Nurushev, S B; Odyniec, G; Ogawa, A; Okorokov, V; Oldenburg, M; Olson, D; Paic, G; Pal, S K; Panebratsev, Y; Panitkin, S Y; Pavlinov, A I; Pawlak, T; Peitzmann, T; Perevoztchikov, V; Perkins, C; Peryt, W; Petrov, V A; Phatak, S C; Picha, R; Planinic, M; Pluta, J; Porile, N; Porter, J; Poskanzer, A M; Potekhin, M; Potrebenikova, E; Potukuchi, B V K S; Prindle, D; Pruneau, C; Putschke, J; Rai, G; Rakness, G; Raniwala, R; Raniwala, S; Ravel, O; Ray, R L; Razin, S V; Reichhold, D; Reid, J G; Renault, G; Retiere, F; Ridiger, A; Ritter, H G; Roberts, J B; Rogachevski, O V; Romero, J L; Rose, A; Roy, C; Ruan, L J; Sahoo, R; Sakrejda, I; Salur, S; Sandweiss, J; Savin, I; Schambach, J; Scharenberg, R P; Schmitz, N; Schroeder, L S; Schweda, K; Seger, J; Seyboth, P; Shahaliev, E; Shao, M; Shao, W; Sharma, M; Shestermanov, K E; Shimanskii, S S; Singaraju, R N; Simon, F; Skoro, G; Smirnov, N; Snellings, R; Sood, G; Sorensen, P; Sowinski, J; Speltz, J; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stock, R; Stolpovsky, A; Strikhanov, M; Stringfellow, B; Struck, C; Suaide, A A P; Sugarbaker, E; Suire, C; Sumbera, M; Surrow, B; Symons, T J M; Szanto de Toledo, A; Szarwas, P; Tai, A; Takahashi, J; Tang, A H; Thein, D; Thomas, J H; Timoshenko, S; Tokarev, M; Tonjes, M B; Trainor, T A; Trentalange, S; Tribble, R E; Tsai, O; Ullrich, T; Underwood, D G; Van Buren, G; VanderMolen, A M; Varma, R; Vasilevski, I; Vasiliev, A N; Vernet, R; Vigdor, S E; Viyogi, Y P; Voloshin, S A; Vznuzdaev, M; Waggoner, W; Wang, F; Wang, G; Wang, G; Wang, X L; Wang, Y; Wang, Z M; Ward, H; Watson, J W; Webb, J C; Wells, R; Westfall, G D; Whitten, C; Wieman, H; Willson, R; Wissink, S W; Witt, R; Wood, J; Wu, J; Xu, N; Xu, Z; Xu, Z Z; Yamamoto, E; Yepes, P; Yurevich, V I; Yuting, B; Zanevski, Y V; Zhang, H; Zhang, W M; Zhang, Z P; Zhaomin, Z P; Zizong, Z P; Zołnierczuk, P A; Zoulkarneev, R; Zoulkarneeva, J; Zubarev, A N

2004-03-05

We report results on rho(770)(0)-->pi(+)pi(-) production at midrapidity in p+p and peripheral Au+Au collisions at sqrt[s(NN)]=200 GeV. This is the first direct measurement of rho(770)(0)-->pi(+)pi(-) in heavy-ion collisions. The measured rho(0) peak in the invariant mass distribution is shifted by approximately 40 MeV/c(2) in minimum bias p+p interactions and approximately 70 MeV/c(2) in peripheral Au+Au collisions. The rho(0) mass shift is dependent on transverse momentum and multiplicity. The modification of the rho(0) meson mass, width, and shape due to phase space and dynamical effects are discussed.

Rho meson decay width in SU(2) gauge theories with 2 fundamental flavours

CERN Document Server

Janowski, Tadeusz; Pica, Claudio

2016-01-01

SU(2) gauge theories with two quark flavours in the fundamental representation are among the most promising theories of composite dynamics describing the electroweak sector. Three out of five Goldstone bosons in these models become the longitudinal components of the W and Z bosons giving them mass. Like in QCD, we expect a spectrum of excitations which appear as resonances in vector boson scattering, in particular the vector resonance corresponding to the rho-meson in QCD. In this talk I will present the preliminary results of the first calculation of the rho-meson decay width in this theory, which is analogous to rho to two pions decay calculation in QCD. The results presented were calculated in a moving frame with total momentum (0,0,1) on two ensembles. Future plans include using 3 moving frames on a larger set of ensembles to extract the resonance parameters more reliably and also take the chiral and continuum limits.

Crucial role of rho-kinase in pressure overload-induced right ventricular hypertrophy and dysfunction in mice.

Science.gov (United States)

Ikeda, Shohei; Satoh, Kimio; Kikuchi, Nobuhiro; Miyata, Satoshi; Suzuki, Kota; Omura, Junichi; Shimizu, Toru; Kobayashi, Kenta; Kobayashi, Kazuto; Fukumoto, Yoshihiro; Sakata, Yasuhiko; Shimokawa, Hiroaki

2014-06-01

Right ventricular (RV) failure is the leading cause of death in various cardiopulmonary diseases, including pulmonary hypertension. It is generally considered that the RV is vulnerable to pressure overload as compared with the left ventricle (LV). However, as compared with LV failure, the molecular mechanisms of RV failure are poorly understood, and hence therapeutic targets of the disorder remain to be elucidated. Thus, we aimed to identify molecular therapeutic targets for RV failure in a mouse model of pressure overload. To induce pressure overload to respective ventricles, we performed pulmonary artery constriction or transverse aortic constriction in mice. We first performed microarray analysis and found that the molecules related to RhoA/Rho-kinase and integrin pathways were significantly upregulated in the RV with pulmonary artery constriction compared with the LV with transverse aortic constriction. Then, we examined the responses of both ventricles to chronic pressure overload in vivo. We demonstrated that compared with transverse aortic constriction, pulmonary artery constriction caused greater extents of mortality, Rho-kinase expression (especially ROCK2 isoform), and oxidative stress in pressure-overloaded RV, reflecting the weakness of the RV in response to pressure overload. Furthermore, mice with myocardial-specific overexpression of dominant-negative Rho-kinase showed resistance to pressure overload-induced hypertrophy and dysfunction associated with reduced oxidative stress. Finally, dominant-negative Rho-kinase mice showed a significantly improved long-term survival in both pulmonary artery constriction and transverse aortic constriction as compared with littermate controls. These results indicate that the Rho-kinase pathway plays a crucial role in RV hypertrophy and dysfunction, suggesting that the pathway is a novel therapeutic target of RV failure in humans. © 2014 American Heart Association, Inc.

Data integration aids understanding of butterfly-host plant networks.

Science.gov (United States)

Muto-Fujita, Ai; Takemoto, Kazuhiro; Kanaya, Shigehiko; Nakazato, Takeru; Tokimatsu, Toshiaki; Matsumoto, Natsushi; Kono, Mayo; Chubachi, Yuko; Ozaki, Katsuhisa; Kotera, Masaaki

2017-03-06

Although host-plant selection is a central topic in ecology, its general underpinnings are poorly understood. Here, we performed a case study focusing on the publicly available data on Japanese butterflies. A combined statistical analysis of plant-herbivore relationships and taxonomy revealed that some butterfly subfamilies in different families feed on the same plant families, and the occurrence of this phenomenon more than just by chance, thus indicating the independent acquisition of adaptive phenotypes to the same hosts. We consequently integrated plant-herbivore and plant-compound relationship data and conducted a statistical analysis to identify compounds unique to host plants of specific butterfly families. Some of the identified plant compounds are known to attract certain butterfly groups while repelling others. The additional incorporation of insect-compound relationship data revealed potential metabolic processes that are related to host plant selection. Our results demonstrate that data integration enables the computational detection of compounds putatively involved in particular interspecies interactions and that further data enrichment and integration of genomic and transcriptomic data facilitates the unveiling of the molecular mechanisms involved in host plant selection.

Data integration aids understanding of butterfly–host plant networks

Science.gov (United States)

Muto-Fujita, Ai; Takemoto, Kazuhiro; Kanaya, Shigehiko; Nakazato, Takeru; Tokimatsu, Toshiaki; Matsumoto, Natsushi; Kono, Mayo; Chubachi, Yuko; Ozaki, Katsuhisa; Kotera, Masaaki

2017-01-01

Although host-plant selection is a central topic in ecology, its general underpinnings are poorly understood. Here, we performed a case study focusing on the publicly available data on Japanese butterflies. A combined statistical analysis of plant–herbivore relationships and taxonomy revealed that some butterfly subfamilies in different families feed on the same plant families, and the occurrence of this phenomenon more than just by chance, thus indicating the independent acquisition of adaptive phenotypes to the same hosts. We consequently integrated plant–herbivore and plant–compound relationship data and conducted a statistical analysis to identify compounds unique to host plants of specific butterfly families. Some of the identified plant compounds are known to attract certain butterfly groups while repelling others. The additional incorporation of insect–compound relationship data revealed potential metabolic processes that are related to host plant selection. Our results demonstrate that data integration enables the computational detection of compounds putatively involved in particular interspecies interactions and that further data enrichment and integration of genomic and transcriptomic data facilitates the unveiling of the molecular mechanisms involved in host plant selection. PMID:28262809

Identification of a single-nucleotide insertion in the promoter region affecting the sodC promoter activity in Brucella neotomae.

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Dina A Moustafa

Full Text Available Brucella neotomae is not known to be associated with clinical disease in any host species. Previous research suggested that B. neotomae might not express detectable levels of Cu/Zn superoxide dismutase (SOD, a periplasmic enzyme known to be involved in protecting Brucella from oxidative bactericidal effects of host phagocytes. This study was undertaken to investigate the genetic basis for the disparity in SOD expression in B. neotomae. Our Western blot and SOD enzyme assay analyses indicated that B. neotomae does express SOD, but at a substantially reduced level. Nucleotide sequence analysis of region upstream to the sodC gene identified a single-nucleotide insertion in the potential promoter region. The same single-nucleotide insertion was also detected in the sodC promoter of B. suis strain Thomsen, belonging to biovar 2 in which SOD expression was undetectable previously. Examination of the sodC promoter activities using translational fusion constructs with E. coli β-galactosidase demonstrated that the B. neotomae and B. suis biovar 2 promoters were very weak in driving gene expression. Site-directed mutation studies indicated that the insertion of A in the B. neotomae sodC promoter reduced the promoter activity. Increasing the level of SOD expression in B. neotomae through complementation with B. abortus sodC gene did not alter the bacterial survival in J774A.1 macrophage-like cells and in tissues of BALB/c and C57BL/6 mice. These results for the first time demonstrate the occurrence of a single-nucleotide polymorphism affecting promoter function and gene expression in Brucella.

Co-extinction in a host-parasite network: identifying key hosts for network stability.

Science.gov (United States)

Dallas, Tad; Cornelius, Emily

2015-08-17

Parasites comprise a substantial portion of total biodiversity. Ultimately, this means that host extinction could result in many secondary extinctions of obligate parasites and potentially alter host-parasite network structure. Here, we examined a highly resolved fish-parasite network to determine key hosts responsible for maintaining parasite diversity and network structure (quantified here as nestedness and modularity). We evaluated four possible host extinction orders and compared the resulting co-extinction dynamics to random extinction simulations; including host removal based on estimated extinction risk, parasite species richness and host level contributions to nestedness and modularity. We found that all extinction orders, except the one based on realistic extinction risk, resulted in faster declines in parasite diversity and network structure relative to random biodiversity loss. Further, we determined species-level contributions to network structure were best predicted by parasite species richness and host family. Taken together, we demonstrate that a small proportion of hosts contribute substantially to network structure and that removal of these hosts results in rapid declines in parasite diversity and network structure. As network stability can potentially be inferred through measures of network structure, our findings may provide insight into species traits that confer stability.

Parasitism of host trees by the Loranthaceae in the region of Douala ...

African Journals Online (AJOL)

The infested host trees belong to 16 species gathered into 12 genus and 10 families. The most parasitized host family is Sterculiaceae. The most sensitive host species to the parasitism of Loranthaceae is P. americana (21.51%), followed by C. nitida (17.27%) and Terminalia mantaly (13.65%). Lauraceae is infested by 7 ...

Fabrication and non-covalent modification of highly oriented thin films of a zeolite-like metal-organic framework (ZMOF) with rho topology

KAUST Repository

Shekhah, Osama; Cadiau, Amandine; Eddaoudi, Mohamed

2015-01-01

Here we report the fabrication of the first thin film of a zeolite-like metal-organic framework (ZMOF) with rho topology (rho-ZMOF-1, ([In48(HImDC)96]48-)n) in a highly oriented fashion on a gold-functionalized substrate. The oriented rho-ZMOF-1

Antinociceptive effect of purine nucleotides.

Science.gov (United States)

Mello, C F; Begnini, J; De-La-Vega, D D; Lopes, F P; Schwartz, C C; Jimenez-Bernal, R E; Bellot, R G; Frussa-Filho, R

1996-10-01

The antinociceptive effect of purine nucleotides administered systematically (sc) was determined using the formalin and writhing tests in adult male albino mice. The mechanisms underlying nucleotide-induced antinociception were investigated by preinjecting the animals (sc) with specific antagonists for opioid (naloxone, 1 mg/kg), purinergic P1 (caffeine, 5, 10, of 30 mg/kg); theophylline, 10 mg/kg) or purinergic P2 receptors (suramin, 100 mg/kg; Coomassie blue, 30-300 mg/kg; quinidine, 10 mg/kg). Adenosine, adenosine monophosphate (AMP), diphosphate (ADP) and triphosphate (ATP) caused a reduction in the number of writhes and in the time of licking the formalin-injected paw. Naloxone had no effect on adenosine- or adenine nucleotide-induced antinociception. Caffeine (30 mg/kg) and theophylline (10 mg/kg) reversed the antinociceptive action of adenosine and adenine nucleotide derivatives in both tests. P2 antagonists did not reverse adenine nucleotide-induced antinociception. These results suggest that antinociceptive effect of adenine nucleotides is mediated by adenosine.

C-terminal β9-strand of the cyclic nucleotide-binding homology domain stabilizes activated states of Kv11.1 channels.

Directory of Open Access Journals (Sweden)

Chai Ann Ng

Full Text Available Kv11.1 potassium channels are important for regulation of the normal rhythm of the heartbeat. Reduced activity of Kv11.1 channels causes long QT syndrome type 2, a disorder that increases the risk of cardiac arrhythmias and sudden cardiac arrest. Kv11.1 channels are members of the KCNH subfamily of voltage-gated K(+ channels. However, they also share many similarities with the cyclic nucleotide gated ion channel family, including having a cyclic nucleotide-binding homology (cNBH domain. Kv11.1 channels, however, are not directly regulated by cyclic nucleotides. Recently, crystal structures of the cNBH domain from mEAG and zELK channels, both members of the KCNH family of voltage-gated potassium channels, revealed that a C-terminal β9-strand in the cNBH domain occupied the putative cyclic nucleotide-binding site thereby precluding binding of cyclic nucleotides. Here we show that mutations to residues in the β9-strand affect the stability of the open state relative to the closed state of Kv11.1 channels. We also show that disrupting the structure of the β9-strand reduces the stability of the inactivated state relative to the open state. Clinical mutations located in this β9-strand result in reduced trafficking efficiency, which suggests that binding of the C-terminal β9-strand to the putative cyclic nucleotide-binding pocket is also important for assembly and trafficking of Kv11.1 channels.

Family ties and economic stability concerns of migrant labour families in Jordan.

Science.gov (United States)

Kamiar, M S; Ismail, H F

1991-12-01

74 labor migrant families from various socioeconomic classes in Amman, Jordan were interviewed to examine changes in relationships among family members, extended family, and neighbors and their concerns about economic stability in the host country, Jordan, and the world market. Another purpose was to determine how current migration policies of the Arab oil-producing countries which prohibit labor migrants from bringing their families to the host country affect labor migration among families. The families consisted of either those who did or did not accompany the labor migrant. Overall labor migration affected unaccompanied families more than accompanied families, e.g., only 19% of the unaccompanied families reported increased family unity compared with 56% of accompanied families. Problems within unaccompanied families increased in 43% of the cases but in only 6% of the accompanied families. Many of these problems resulted in children dropping out of school which reflected the control fathers had within the family, separation, or divorce. Yet labor migration reduced family ties with extended family members and neighbors almost equally for both groups. Accompanied families were not as concerned about economic stability in Jordan as unaccompanied families (38% vs. 50%). Perhaps these families tended not to invest remittances received from the labor migrants working in Arab oil-producing countries in Jordan. Both groups were quite concerned about the economic stability in the host countries (66% and 72%, respectively) and the world market (59% and 62%, respectively), however. Since family unity suffers when families do not accompany labor migrants, it is suggested that oil-producing nations that depend on foreign labor should guarantee family unity as a human right.

Serine34 phosphorylation of RHO guanine dissociation inhibitor (RHOGDI{alpha}) links signaling from conventional protein kinase C to RHO GTPase in cell adhesion

DEFF Research Database (Denmark)

Dovas, Athanassios; Choi, Youngsil; Yoneda, Atsuko

2010-01-01

. Phosphospecific antibodies reveal endogenous phosphorylation in several cell types that is sensitive to adhesion events triggered, for example, by hepatocyte growth factor. Phosphorylation is also sensitive to PKC inhibition. Together with FRET microscopy sensing GTP-RhoA levels, the data reveal a common pathway...

Kindlin-2 Association with Rho GDP-Dissociation Inhibitor α Suppresses Rac1 Activation and Podocyte Injury.

Science.gov (United States)

Sun, Ying; Guo, Chen; Ma, Ping; Lai, Yumei; Yang, Fan; Cai, Jun; Cheng, Zhehao; Zhang, Kuo; Liu, Zhongzhen; Tian, Yeteng; Sheng, Yue; Tian, Ruijun; Deng, Yi; Xiao, Guozhi; Wu, Chuanyue

2017-12-01

Alteration of podocyte behavior is critically involved in the development and progression of many forms of human glomerular diseases. The molecular mechanisms that control podocyte behavior, however, are not well understood. Here, we investigated the role of Kindlin-2, a component of cell-matrix adhesions, in podocyte behavior in vivo Ablation of Kindlin-2 in podocytes resulted in alteration of actin cytoskeletal organization, reduction of the levels of slit diaphragm proteins, effacement of podocyte foot processes, and ultimately massive proteinuria and death due to kidney failure. Through proteomic analyses and in vitro coimmunoprecipitation experiments, we identified Rho GDP-dissociation inhibitor α (RhoGDI α ) as a Kindlin-2-associated protein. Loss of Kindlin-2 in podocytes significantly reduced the expression of RhoGDI α and resulted in the dissociation of Rac1 from RhoGDI α , leading to Rac1 hyperactivation and increased motility of podocytes. Inhibition of Rac1 activation effectively suppressed podocyte motility and alleviated the podocyte defects and proteinuria induced by the loss of Kindlin-2 in vivo Our results identify a novel Kindlin-2-RhoGDI α -Rac1 signaling axis that is critical for regulation of podocyte structure and function in vivo and provide evidence that it may serve as a useful target for therapeutic control of podocyte injury and associated glomerular diseases. Copyright © 2017 by the American Society of Nephrology.

Raf-1/CK2 and RhoA/ROCK signaling promote TNF-α-mediated endothelial apoptosis via regulating vimentin cytoskeleton.

Science.gov (United States)

Yang, Lifeng; Tang, Lian; Dai, Fan; Meng, Guoliang; Yin, Runting; Xu, Xiaole; Yao, Wenjuan

2017-08-15

Both RhoA/ROCK and Raf-1/CK2 pathway play essential roles in cell proliferation, apoptosis, differentiation, and multiple other common cellular functions. We previously reported that vimentin is responsible for TNF-α-induced cell apoptosis. Herein, we investigated the regulation of RhoA/ROCK and Raf-1/CK2 signaling on vimentin filaments and endothelial apoptosis mediated by TNF-α. Treatment with TNF-α significantly induced the activation of RhoA and ROCK, and the expression of ROCK1. RhoA deficiency could obviously inhibit ROCK activation and ROCK1 expression induced by TNF-α. Both RhoA deficiency and ROCK activity inhibition (Y-27632) greatly inhibited endothelial apoptosis and preserved cell viability in TNF-α-induced human umbilical vein endothelial cells (HUVECs). Also vimentin phosphorylation and the remodeling of vimentin or phospho-vimentin induced by TNF-α were obviously attenuated by RhoA suppression and ROCK inhibition. TNF-α-mediated vimentin cleavage was significantly inhibited by RhoA suppression and ROCK inhibition through decreasing the activation of caspase3 and 8. Furthermore, TNF-α treatment greatly enhanced the activation of Raf-1. Suppression of Raf-1 or CK2 by its inhibitor (GW5074 or TBB) blocked vimentin phosphorylation, remodeling and endothelial apoptosis, and preserved cell viability in TNF-α-induced HUVECs. However, Raf-1 inhibition showed no significant effect on TNF-α-induced ROCK expression and activation, suggesting that the regulation of Raf-1/CK2 signaling on vimentin was independent of ROCK. Taken together, these results indicate that both RhoA/ROCK and Raf-1/CK2 pathway are responsible for TNF-α-mediated endothelial cytotoxicity via regulating vimentin cytoskeleton. Copyright © 2017 Elsevier B.V. All rights reserved.

Mechanism of host substrate acetylation by a YopJ family effector.

Science.gov (United States)

Zhang, Zhi-Min; Ma, Ka-Wai; Gao, Linfeng; Hu, Zhenquan; Schwizer, Simon; Ma, Wenbo; Song, Jikui

2017-07-24

The Yersinia outer protein J (YopJ) family of bacterial effectors depends on a novel acetyltransferase domain to acetylate signalling proteins from plant and animal hosts. However, the underlying mechanism is unclear. Here, we report the crystal structures of PopP2, a YopJ effector produced by the plant pathogen Ralstonia solanacearum, in complex with inositol hexaphosphate (InsP 6 ), acetyl-coenzyme A (AcCoA) and/or substrate Resistance to Ralstonia solanacearum 1 (RRS1-R) WRKY . PopP2 recognizes the WRKYGQK motif of RRS1-R WRKY to position a targeted lysine in the active site for acetylation. Importantly, the PopP2-RRS1-R WRKY association is allosterically regulated by InsP 6 binding, suggesting a previously unidentified role of the eukaryote-specific cofactor in substrate interaction. Furthermore, we provide evidence for the reaction intermediate of PopP2-mediated acetylation, an acetyl-cysteine covalent adduct, lending direct support to the 'ping-pong'-like catalytic mechanism proposed for YopJ effectors. Our study provides critical mechanistic insights into the virulence activity of YopJ class of acetyltransferases.

Inverse relationship between TCTP/RhoA and p53/ /cyclin A/actin expression in ovarian cancer cells Inverse relationship between TCTP/RhoA and p53/ /cyclin A/actin expression in ovarian cancer cells

Directory of Open Access Journals (Sweden)

Malgorzata Kloc

2012-10-01

Full Text Available The translationally controlled tumor protein (TCTP plays a role in cell growth, cell cycle and cancer
progression. TCTP controls negatively the stability of the p53 tumor suppressor protein and interacts with the
cellular cytoskeleton. The deregulation of the actin and cytokeratin cytoskeleton is responsible for the increased
migratory activity of tumor cells and is linked with poor patient outcome. Recent studies indicate that cyclin A,
a key regulator of cell cycle, controls actin organization and negatively regulates cell motility via regulation of RhoA
expression. We studied the organization of actin and cytokeratin cytoskeleton and the expression of TCTP, p53,
cyclin A, RhoA and actin in HIO180 non-transformed ovarian epithelial cells, and OVCAR3 and SKOV3 (expressing
low level of inducible p53 ovarian epithelial cancer cells with different metastatic potential. Immunostaining
and ultrastructural analyses illustrated a dramatic difference in the organization of the cytokeratin and actin
filaments in non-transformed versus cancer cell lines. We also determined that there is an inverse relationship between
the level of TCTP/RhoA and actin/p53/cyclin A expression in ovarian cancer cell lines. This previously unidentified
negative relationship between TCTP/RhoA and actin/p53/cyclin A may suggest that this interaction is linked
with the high aggressiveness of ovarian cancers.The translationally controlled tumor protein (TCTP plays a role in cell growth, cell cycle and cancer
progression. TCTP controls negatively the stability of the p53 tumor suppressor protein and interacts with the
cellular cytoskeleton. The deregulation of the actin and cytokeratin cytoskeleton is responsible for the increased
migratory activity of tumor cells and is linked with poor patient outcome. Recent studies indicate that cyclin A,
a key regulator of cell cycle, controls actin organization

The arabidopsis cyclic nucleotide interactome

KAUST Repository

Donaldson, Lara Elizabeth

2016-05-11

Background Cyclic nucleotides have been shown to play important signaling roles in many physiological processes in plants including photosynthesis and defence. Despite this, little is known about cyclic nucleotide-dependent signaling mechanisms in plants since the downstream target proteins remain unknown. This is largely due to the fact that bioinformatics searches fail to identify plant homologs of protein kinases and phosphodiesterases that are the main targets of cyclic nucleotides in animals. Methods An affinity purification technique was used to identify cyclic nucleotide binding proteins in Arabidopsis thaliana. The identified proteins were subjected to a computational analysis that included a sequence, transcriptional co-expression and functional annotation analysis in order to assess their potential role in plant cyclic nucleotide signaling. Results A total of twelve cyclic nucleotide binding proteins were identified experimentally including key enzymes in the Calvin cycle and photorespiration pathway. Importantly, eight of the twelve proteins were shown to contain putative cyclic nucleotide binding domains. Moreover, the identified proteins are post-translationally modified by nitric oxide, transcriptionally co-expressed and annotated to function in hydrogen peroxide signaling and the defence response. The activity of one of these proteins, GLYGOLATE OXIDASE 1, a photorespiratory enzyme that produces hydrogen peroxide in response to Pseudomonas, was shown to be repressed by a combination of cGMP and nitric oxide treatment. Conclusions We propose that the identified proteins function together as points of cross-talk between cyclic nucleotide, nitric oxide and reactive oxygen species signaling during the defence response.

Rho proteins − the key regulators of cytoskeleton in the progression of mitosis and cytokinesis

Directory of Open Access Journals (Sweden)

Anna Klimaszewska

2011-11-01

Full Text Available The Rho proteins are members of the Ras superfamily of small GTPases. They are thought to be crucial regulators of multiple signal transduction pathways that influence a wide range of cellular functions, including migration, membrane trafficking, adhesion, polarity and cell shape changes. Thanks to their ability to control the assembly and organization of the actin and microtubule cytoskeletons, Rho GTPases are known to regulate mitosis and cytokinesis progression. These proteins are required for formation and rigidity of the cortex during mitotic cell rounding, mitotic spindle formation and attachment of the spindle microtubules to the kinetochore. In addition, during cytokinesis, they are involved in promoting division plane determination, contractile ring and cleavage furrow formation and abscission. They are also known as regulators of cell cycle progression at the G1/S and G2/M transition. Thus, the signal transduction pathways in which Rho proteins participate, appear to connect dynamics of actin and microtubule cytoskeletons to cell cycle progression. We review the current state of knowledge concerning the molecular mechanisms by which Rho GTPase signaling regulates remodeling of actin and microtubule cytoskeletons in order to control cell division progression.

Identification of cyclic nucleotide gated channels using regular expressions

KAUST Repository

Zelman, Alice K.

2013-09-03

Cyclic nucleotide-gated channels (CNGCs) are nonselective cation channels found in plants, animals, and some bacteria. They have a six-transmembrane/one- pore structure, a cytosolic cyclic nucleotide-binding domain, and a cytosolic calmodulin-binding domain. Despite their functional similarities, the plant CNGC family members appear to have different conserved amino acid motifs within corresponding functional domains than animal and bacterial CNGCs do. Here we describe the development and application of methods employing plant CNGC-specific sequence motifs as diagnostic tools to identify novel candidate channels in different plants. These methods are used to evaluate the validity of annotations of putative orthologs of CNGCs from plant genomes. The methods detail how to employ regular expressions of conserved amino acids in functional domains of annotated CNGCs and together with Web tools such as PHI-BLAST and ScanProsite to identify novel candidate CNGCs in species including Physcomitrella patens. © Springer Science+Business Media New York 2013.

Building the library of RNA 3D nucleotide conformations using the clustering approach

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Zok Tomasz

2015-09-01

Full Text Available An increasing number of known RNA 3D structures contributes to the recognition of various RNA families and identification of their features. These tasks are based on an analysis of RNA conformations conducted at different levels of detail. On the other hand, the knowledge of native nucleotide conformations is crucial for structure prediction and understanding of RNA folding. However, this knowledge is stored in structural databases in a rather distributed form. Therefore, only automated methods for sampling the space of RNA structures can reveal plausible conformational representatives useful for further analysis. Here, we present a machine learning-based approach to inspect the dataset of RNA three-dimensional structures and to create a library of nucleotide conformers. A median neural gas algorithm is applied to cluster nucleotide structures upon their trigonometric description. The clustering procedure is two-stage: (i backbone- and (ii ribose-driven. We show the resulting library that contains RNA nucleotide representatives over the entire data, and we evaluate its quality by computing normal distribution measures and average RMSD between data points as well as the prototype within each cluster.

cAMP-induced activation of protein kinase A and p190B RhoGAP mediates down-regulation of TC10 activity at the plasma membrane and neurite outgrowth.

Science.gov (United States)

Koinuma, Shingo; Takeuchi, Kohei; Wada, Naoyuki; Nakamura, Takeshi

2017-11-01

Cyclic AMP plays a pivotal role in neurite growth. During outgrowth, a trafficking system supplies membrane at growth cones. However, the cAMP-induced signaling leading to the regulation of membrane trafficking remains unknown. TC10 is a Rho family GTPase that is essential for specific types of vesicular trafficking. Recent studies have shown a role of TC10 in neurite growth in NGF-treated PC12 cells. Here, we investigated a mechanical linkage between cAMP and TC10 in neuritogenesis. Plasmalemmal TC10 activity decreased abruptly after cAMP addition in neuronal cells. TC10 was locally inactivated at extending neurite tips in cAMP-treated PC12 cells. TC10 depletion led to a decrease in cAMP-induced neurite outgrowth. Constitutively active TC10 could not rescue this growth reduction, supporting our model for a role of GTP hydrolysis of TC10 in neuritogenesis by accelerating vesicle fusion. The cAMP-induced TC10 inactivation was mediated by PKA. Considering cAMP-induced RhoA inactivation, we found that p190B, but not p190A, mediated inactivation of TC10 and RhoA. Upon cAMP treatment, p190B was recruited to the plasma membrane. STEF depletion and Rac1-N17 expression reduced cAMP-induced TC10 inactivation. Together, the PKA-STEF-Rac1-p190B pathway leading to inactivation of TC10 and RhoA at the plasma membrane plays an important role in cAMP-induced neurite outgrowth. © 2017 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

Exclusive {rho}{sup 0} meson cross section ratios on deuterium and hydrogen targets

Energy Technology Data Exchange (ETDEWEB)

Osborne, A.G.S.

2006-08-15

The HERMES experiment is a large forward angle spectrometer located at the HERA accelerator ring at DESY, Hamburg. This thesis presents the analysis of the kinematic dependencies of {rho}{sup 0} vector meson production on hydrogen and deuterium targets. The relative gluon and quark contribution to the {rho}{sup 0} production amplitude is expected to depend on the kinematical variable x{sub Bj}, and by measuring the ratio of {rho}{sup 0} electroproduction cross sections on deuterium and hydrogen from HERMES data this dependence is confirmed. This thesis describes the methods used to extract the cross section ratio from the HERMES data taken between the years 1996 and 2000 and compares the results with the theoretical predictions. Until 2005 the missing mass resolution of the HERMES spectrometer was only sufficient to allow exclusivity at the level of a data sample. The HERMES Recoil Detector, installed in early 2006, is an upgrade which will augment the HERMES spectrometer by establishing exclusivity at the event level and therefore improving the resolution to which various kinematical variables may be reconstructed. Additionally, the Recoil Detector will contribute to the overall background suppression capability of the HERMES spectrometer. These improvements will provide a strong reduction in the statistical uncertainties present in the {rho}{sup 0}-analysis and other analyses at HERMES. The Recoil Detector critically relies on its track reconstruction software to enable its capability to provide event level exclusive measurements. This tracking code is presented in detail. (orig.)

A genome-wide survey for host response of silkworm, Bombyx mori during pathogen Bacillus bombyseptieus infection.

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Lulin Huang

Full Text Available Host-pathogen interactions are complex relationships, and a central challenge is to reveal the interactions between pathogens and their hosts. Bacillus bombysepticus (Bb which can produces spores and parasporal crystals was firstly separated from the corpses of the infected silkworms (Bombyx mori. Bb naturally infects the silkworm can cause an acute fuliginosa septicaemia and kill the silkworm larvae generally within one day in the hot and humid season. Bb pathogen of the silkworm can be used for investigating the host responses after the infection. Gene expression profiling during four time-points of silkworm whole larvae after Bb infection was performed to gain insight into the mechanism of Bb-associated host whole body effect. Genome-wide survey of the host genes demonstrated many genes and pathways modulated after the infection. GO analysis of the induced genes indicated that their functions could be divided into 14 categories. KEGG pathway analysis identified that six types of basal metabolic pathway were regulated, including genetic information processing and transcription, carbohydrate metabolism, amino acid and nitrogen metabolism, nucleotide metabolism, metabolism of cofactors and vitamins, and xenobiotic biodegradation and metabolism. Similar to Bacillus thuringiensis (Bt, Bb can also induce a silkworm poisoning-related response. In this process, genes encoding midgut peritrophic membrane proteins, aminopeptidase N receptors and sodium/calcium exchange protein showed modulation. For the first time, we found that Bb induced a lot of genes involved in juvenile hormone synthesis and metabolism pathway upregulated. Bb also triggered the host immune responses, including cellular immune response and serine protease cascade melanization response. Real time PCR analysis showed that Bb can induce the silkworm systemic immune response, mainly by the Toll pathway. Anti-microorganism peptides (AMPs, including of Attacin, Lebocin, Enbocin, Gloverin

Reduction of Fibrogenesis by Selective Delivery of a Rho Kinase Inhibitor to Hepatic Stellate Cells in Mice

NARCIS (Netherlands)

van Beuge, M. M.; Prakash, J.; Lacombe, M.; Gosens, R.; Post, E.; Reker-Smit, C.; Beljaars, L.; Poelstra, K.

One of the pathways activated during liver fibrosis is the Rho kinase pathway, which regulates activation, migration, and contraction of hepatic stellate cells (HSC). Inhibition of this kinase by the Rho kinase inhibitor Y27632 [(+)-(R)-trans-4-(1-aminoethyl)-N-(4-pyridyl)cyclohexanecarboxamide

Coherent rho+ production in neutrino-neon interactions

International Nuclear Information System (INIS)

Ballagh, H.C.; Bingham, H.H.; Lawry, T.J.

1988-01-01

Coherent rho + production on neon nuclei has been observed in charged-current events in a neutrino bubble-chamber experiment. The incident neutrino energy was 10--320 GeV, with a median event energy of 80 GeV. The rate per charged-current event was (0.28 +- 0.10)%. Comparison was made to vector-meson-dominance predictions; agreement with the overall rate, but disagreement at high neutrino energies and at high Q 2 , was found

Influence of the host contact sequence on the outcome of competition among aspergillus flavus isolates during host tissue invasion.

Science.gov (United States)

Mehl, H L; Cotty, P J

2011-03-01

Biological control of aflatoxin contamination by Aspergillus flavus is achieved through competitive exclusion of aflatoxin producers by atoxigenic strains. Factors dictating the extent to which competitive displacement occurs during host infection are unknown. The role of initial host contact in competition between pairs of A. flavus isolates coinfecting maize kernels was examined. Isolate success during tissue invasion and reproduction was assessed by quantification of isolate-specific single nucleotide polymorphisms using pyrosequencing. Isolates were inoculated either simultaneously or 1 h apart. Increased success during competition was conferred to the first isolate to contact the host independent of that isolate's innate competitive ability. The first-isolate advantage decreased with the conidial concentration, suggesting capture of limited resources on kernel surfaces contributes to competitive exclusion. Attempts to modify access to putative attachment sites by either coating kernels with dead conidia or washing kernels with solvents did not influence the success of the first isolate, suggesting competition for limited attachment sites on kernel surfaces does not mediate first-isolate advantage. The current study is the first to demonstrate an immediate competitive advantage conferred to A. flavus isolates upon host contact and prior to either germ tube emergence or host colonization. This suggests the timing of host contact is as important to competition during disease cycles as innate competitive ability. Early dispersal to susceptible crop components may allow maintenance within A. flavus populations of genetic types with low competitive ability during host tissue invasion.

Structural determinants for antagonist pharmacology that distinguish the rho1 GABAC receptor from GABAA receptors.

Science.gov (United States)

Zhang, Jianliang; Xue, Fenqin; Chang, Yongchang

2008-10-01

GABA receptor (GABAR) types C (GABACR) and A (GABAAR) are both GABA-gated chloride channels that are distinguished by their distinct competitive antagonist properties. The structural mechanism underlying these distinct properties is not well understood. In this study, using previously identified binding residues as a guide, we made individual or combined mutations of nine binding residues in the rho1 GABACR subunit to their counterparts in the alpha1beta2gamma2 GABAAR or reverse mutations in alpha1 or beta2 subunits. The mutants were expressed in Xenopus laevis oocytes and tested for sensitivities of GABA-induced currents to the GABAA and GABAC receptor antagonists. The results revealed that bicuculline insensitivity of the rho1 GABACR was mainly determined by Tyr106, Phe138 and Phe240 residues. Gabazine insensitivity of the rho1 GABACR was highly dependent on Tyr102, Tyr106, and Phe138. The sensitivity of the rho1 GABACR to 3-aminopropyl-phosphonic acid and its analog 3-aminopropyl-(methyl)phosphinic acid mainly depended on residues Tyr102, Val140, FYS240-242, and Phe138. Thus, the residues Tyr102, Tyr106, Phe138, and Phe240 in the rho1 GABACR are major determinants for its antagonist properties distinct from those in the GABAAR. In addition, Val140 in the GABACR contributes to 3-APA binding. In conclusion, we have identified the key structural elements underlying distinct antagonist properties for the GABACR. The mechanistic insights were further extended and discussed in the context of antagonists docking to the homology models of GABAA or GABAC receptors.

START-GAP3/DLC3 is a GAP for RhoA and Cdc42 and is localized in focal adhesions regulating cell morphology

International Nuclear Information System (INIS)

Kawai, Katsuhisa; Kiyota, Minoru; Seike, Junichi; Deki, Yuko; Yagisawa, Hitoshi

2007-01-01

In the human genome there are three genes encoding RhoGAPs that contain the START (steroidogenic acute regulatory protein (StAR)-related lipid transfer)-domain. START-GAP3/DLC3 is a tumor suppressor gene similar to two other human START-GAPs known as DLC1 or DLC2. Although expression of START-GAP3/DLC3 inhibits the proliferation of cancer cells, its molecular function is not well understood. In this study we carried out biochemical characterization of START-GAP3/DLC3, and explored the effects of its expression on cell morphology and intracellular localization. We found that START-GAP3/DLC3 serves as a stimulator of PLCδ1 and as a GAP for both RhoA and Cdc42 in vitro. Moreover, we found that the GAP activity is responsible for morphological changes. The intracellular localization of endogenous START-GAP3/DLC3 was explored by immunocytochemistry and was revealed in focal adhesions. These results indicate that START-GAP3/DLC3 has characteristics similar to other START-GAPs and the START-GAP family seems to share common characteristics

Rho Ophiuchi Cloud Core Extinction Map

Science.gov (United States)