c-Jun N-terminal kinase 3 expression in the retina of ocular hypertension mice: a possible target to reduce ganglion cell apoptosis

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Yue He

2015-01-01

Full Text Available Glaucoma, a type of optic neuropathy, is characterized by the loss of retinal ganglion cells. It remains controversial whether c-Jun N-terminal kinase (JNK participates in the apoptosis of retinal ganglion cells in glaucoma. This study sought to explore a possible mechanism of action of JNK signaling pathway in glaucoma-induced retinal optic nerve damage. We established a mouse model of chronic ocular hypertension by reducing the aqueous humor followed by photocoagulation using the laser ignition method. Results showed significant pathological changes in the ocular tissues after the injury. Apoptosis of retinal ganglion cells increased with increased intraocular pressure, as did JNK3 mRNA expression in the retina. These data indicated that the increased expression of JNK3 mRNA was strongly associated with the increase in intraocular pressure in the retina, and correlated positively with the apoptosis of retinal ganglion cells.

EGCG-targeted p57/KIP2 reduces tumorigenicity of oral carcinoma cells: Role of c-Jun N-terminal kinase

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Yamamoto, Tetsuya; Digumarthi, Hari; Aranbayeva, Zina; Wataha, John; Lewis, Jill; Messer, Regina; Qin, Haiyan; Dickinson, Douglas; Osaki, Tokio; Schuster, George S.; Hsu, Stephen

2007-01-01

The green tea polyphenol epigallocatechin-3-gallate (EGCG) regulates gene expression differentially in tumor and normal cells. In normal human primary epidermal keratinocytes (NHEK), one of the key mediators of EGCG action is p57/KIP2, a cyclin-dependent kinase (CDK) inhibitor. EGCG potently induces p57 in NHEK, but not in epithelial cancer cells. In humans, reduced expression of p57 often is associated with advanced tumors, and tumor cells with inactivated p57 undergo apoptosis when exposed to EGCG. The mechanism of p57 induction by EGCG is not well understood. Here, we show that in NHEK, EGCG-induces p57 via the p38 mitogen-activated protein kinase (MAPK) signaling pathway. In p57-negative tumor cells, JNK signaling mediates EGCG-induced apoptosis, and exogenous expression of p57 suppresses EGCG-induced apoptosis via inhibition of c-Jun N-terminal kinase (JNK). We also found that restoration of p57 expression in tumor cells significantly reduced tumorigenicity in athymic mice. These results suggest that p57 expression may be an useful indicator for the clinical course of cancers, and could be potentially useful as a target for cancer therapies

Momordica charantia polysaccharides could protect against cerebral ischemia/reperfusion injury through inhibiting oxidative stress mediated c-Jun N-terminal kinase 3 signaling pathway.

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Gong, Juanjuan; Sun, Fumou; Li, Yihang; Zhou, Xiaoling; Duan, Zhenzhen; Duan, Fugang; Zhao, Lei; Chen, Hansen; Qi, Suhua; Shen, Jiangang

2015-04-01

Momordica charantia (MC) is a medicinal plant for stroke treatment in Traditional Chinese Medicine, but its active compounds and molecular targets are unknown yet. M. charantia polysaccharide (MCP) is one of the important bioactive components in MC. In the present study, we tested the hypothesis that MCP has neuroprotective effects against cerebral ischemia/reperfusion injury through scavenging superoxide (O2(-)), nitric oxide (NO) and peroxynitrite (ONOO(-)) and inhibiting c-Jun N-terminal protein kinase (JNK3) signaling cascades. We conducted experiments with in vivo global and focal cerebral ischemia/reperfusion rat models and in vitro oxygen glucose deprivation (OGD) neural cells. The effects of MCP on apoptotic cell death and infarction volume, the bioactivities of scavenging O2(-), NO and ONOO(-), inhibiting lipid peroxidation and modulating JNK3 signaling pathway were investigated. Major results are summarized as below: (1) MCP dose-dependently attenuated apoptotic cell death in neural cells under OGD condition in vitro and reduced infarction volume in ischemic brains in vivo; (2) MCP had directing scavenging effects on NO, O2(-) and ONOO(-) and inhibited lipid peroxidation; (3) MCP inhibited the activations of JNK3/c-Jun/Fas-L and JNK3/cytochrome C/caspases-3 signaling cascades in ischemic brains in vivo. Taken together, we conclude that MCP could be a promising neuroprotective ingredient of M. charantia and its mechanisms could be at least in part attributed to its antioxidant activities and inhibiting JNK3 signaling cascades during cerebral ischemia/reperfusion injury. Copyright © 2014 Elsevier Ltd. All rights reserved.

A feed-forward regulation of endothelin receptors by c-Jun in human non-pigmented ciliary epithelial cells and retinal ganglion cells.

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Junming Wang

Full Text Available c-Jun, c-Jun N-terminal kinase(JNK and endothelin B (ETB receptor have been shown to contribute to the pathogenesis of glaucoma. Previously, we reported that an increase of c-Jun and CCAAT/enhancer binding protein β (C/EBPβ immunohistostaining is associated with upregulation of the ETB receptor within the ganglion cell layer of rats with elevated intraocular pressure (IOP. In addition, both transcription factors regulate the expression of the ETB receptor in human non-pigmented ciliary epithelial cells (HNPE. The current study addressed the mechanisms by which ET-1 produced upregulation of ET receptors in primary rat retinal ganglion cells (RGCs and HNPE cells. Treatment of ET-1 and ET-3 increased the immunocytochemical staining of c-Jun and C/EBPβ in primary rat RGCs and co-localization of both transcription factors was observed. A marked increase in DNA binding activity of AP-1 and C/EBPβ as well as elevated protein levels of c-Jun and c-Jun-N-terminal kinase (JNK were detected following ET-1 treatment in HNPE cells. Overexpression of ETA or ETB receptor promoted the upregulation of c-Jun and also elevated its promoter activity. In addition, upregulation of C/EBPβ augmented DNA binding and mRNA expression of c-Jun, and furthermore, the interaction of c-Jun and C/EBPβ was confirmed using co-immunoprecipitation. Apoptosis of HNPE cells was identified following ET-1 treatment, and overexpression of the ETA or ETB receptor produced enhanced apoptosis. ET-1 mediated upregulation of c-Jun and C/EBPβ and their interaction may represent a novel mechanism contributing to the regulation of endothelin receptor expression. Reciprocally, c-Jun was also found to regulate the ET receptors and C/EBPβ appeared to play a regulatory role in promoting expression of c-Jun. Taken together, the data suggests that ET-1 triggers the upregulation of c-Jun through both ETA and ETB receptors, and conversely c-Jun also upregulates endothelin receptor expression

Tumor Necrosis Factor-α and Apoptosis Signal-Regulating Kinase 1 Control Reactive Oxygen Species Release, Mitochondrial Autophagy and C-Jun N-Terminal Kinase/P38 Phosphorylation During Necrotizing Enterocolitis

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Naira Baregamian

2009-01-01

Full Text Available Background: Oxidative stress and inflammation may contribute to the disruption of the protective gut barrier through various mechanisms; mitochondrial dysfunction resulting from inflammatory and oxidative injury may potentially be a significant source of apoptosis during necrotizing enterocolitis (NEC. Tumor necrosis factor (TNFα is thought to generate reactive oxygen species (ROS and activate the apoptosis signal-regulating kinase 1 (ASK1-c-Jun N-terminal kinase (JNK/p38 pathway. Hence, the focus of our study was to examine the effects of TNFα/ROs on mitochondrial function, ASK1-JNK/p38 cascade activation in intestinal epithelial cells during NEC.

C-Jun N-Terminal Kinase 2 Promotes Liver Injury via the Mitochondrial Permeability Transition after Hemorrhage and Resuscitation

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Christoph Czerny

2012-01-01

Full Text Available Hemorrhagic shock leads to hepatic hypoperfusion and activation of mitogen-activated stress kinases (MAPK like c-Jun N-terminal kinase (JNK 1 and 2. Our aim was to determine whether mitochondrial dysfunction leading to hepatic necrosis and apoptosis after hemorrhage/resuscitation (H/R was dependent on JNK2. Under pentobarbital anesthesia, wildtype (WT and JNK2 deficient (KO mice were hemorrhaged to 30 mm Hg for 3 h and then resuscitated with shed blood plus half the volume of lactated Ringer’s solution. Serum alanine aminotransferase (ALT, necrosis, apoptosis and oxidative stress were assessed 6 h after resuscitation. Mitochondrial polarization was assessed by intravital microscopy. After H/R, ALT in WT-mice increased from 130 U/L to 4800 U/L. In KO-mice, ALT after H/R was blunted to 1800 U/l (P<0.05. Necrosis, caspase-3 activity and ROS were all substantially decreased in KO compared to WT mice after H/R. After sham operation, intravital microscopy revealed punctate mitochondrial staining by rhodamine 123 (Rh123, indicating normal mitochondrial polarization. At 4 h after H/R, Rh123 staining became dim and diffuse in 58% of hepatocytes, indicating depolarization and onset of the mitochondrial permeability transition (MPT. By contrast, KO mice displayed less depolarization after H/R (23%, P<0.05. In conclusion, JNK2 contributes to MPT-mediated liver injury after H/R.

Polymeric immunoglobulin receptor-mediated invasion of Streptococcus pneumoniae into host cells requires a coordinate signaling of SRC family of protein-tyrosine kinases, ERK, and c-Jun N-terminal kinase.

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Agarwal, Vaibhav; Asmat, Tauseef M; Dierdorf, Nina I; Hauck, Christof R; Hammerschmidt, Sven

2010-11-12

Streptococcus pneumoniae are commensals of the human nasopharynx with the capacity to invade mucosal respiratory cells. PspC, a pneumococcal surface protein, interacts with the human polymeric immunoglobulin receptor (pIgR) to promote bacterial adherence to and invasion into epithelial cells. Internalization of pneumococci requires the coordinated action of actin cytoskeleton rearrangements and the retrograde machinery of pIgR. Here, we demonstrate the involvement of Src protein-tyrosine kinases (PTKs), focal adhesion kinase (FAK), extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) but not p38 mitogen-activated protein kinases (MAPK) in pneumococcal invasion via pIgR. Pharmacological inhibitors of PTKs and MAPKs and genetic interference with Src PTK and FAK functions caused a significant reduction of pIgR-mediated pneumococcal invasion but did not influence bacterial adhesion to host cells. Furthermore, pneumococcal ingestion by host cells induces activation of ERK1/2 and JNK. In agreement with activated JNK, its target molecule and DNA-binding protein c-Jun was phosphorylated. We also show that functionally active Src PTK is essential for activation of ERK1/2 upon pneumococcal infections. In conclusion, these data illustrate the importance of a coordinated signaling between Src PTKs, ERK1/2, and JNK during PspC-pIgR-mediated uptake of pneumococci by host epithelial cells.

Distinctive functions of Syk N-terminal and C-terminal SH2 domains in the signaling cascade elicited by oxidative stress in B cells.

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Ding, J; Takano, T; Hermann, P; Gao, S; Han, W; Noda, C; Yanagi, S; Yamamura, H

2000-05-01

Syk plays a crucial role in the transduction of oxidative stress signaling. In this paper, we investigated the roles of Src homology 2 (SH2) domains of Syk in oxidative stress signaling, using Syk-negative DT40 cells expressing the N- or C-terminal SH2 domain mutant [mSH2(N) or mSH2(C)] of Syk. Tyrosine phosphorylation of Syk in cells expressing mSH2(N) Syk after H(2)O(2) treatment was higher than that in cells expressing wild-type Syk or mSH2(C) Syk. The tyrosine phosphorylation of wild-type Syk and mSH2(C) Syk, but not that of mSH2(N), was sensitive to PP2, a specific inhibitor of Src-family protein-tyrosine kinase. In oxidative stress, the C-terminal SH2 domain of Syk was demonstrated to be required for induction of tyrosine phosphorylation of cellular proteins, phospholipase C (PLC)-gamma2 phosphorylation, inositol 1,4, 5-triphosphate (IP(3)) generation, Ca(2)(+) release from intracellular stores, and c-Jun N-terminal kinase activation. In contrast, in mSH2(N) Syk-expressing cells, tyrosine phosphorylation of intracellular proteins including PLC-gamma2 was markedly induced in oxidative stress. The enhanced phosphorylation of mSH2(N) Syk and PLC-gamma2, however, did not link to Ca(2)(+) mobilization from intracellular pools and IP(3) generation. Thus, the N- and C-terminal SH2 domains of Syk possess distinctive functions in oxidative stress signaling.

Overexpressed DNA polymerase iota regulated by JNK/c-Jun contributes to hypermutagenesis in bladder cancer.

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Yuan, Fang; Xu, Zhigang; Yang, Mingzhen; Wei, Quanfang; Zhang, Yi; Yu, Jin; Zhi, Yi; Liu, Yang; Chen, Zhiwen; Yang, Jin

2013-01-01

Human DNA polymerase iota (pol ι) possesses high error-prone DNA replication features and performs translesion DNA synthesis. It may be specialized and strictly regulated in normal mammalian cells. Dysregulation of pol ι may contribute to the acquisition of a mutator phenotype. However, there are few reports describing the transcription regulatory mechanism of pol ι, and there is controversy regarding its role in carcinogenesis. In this study, we performed the deletion and point-mutation experiment, EMSA, ChIP, RNA interference and western blot assay to prove that c-Jun activated by c-Jun N-terminal kinase (JNK) regulates the transcription of pol ι in normal and cancer cells. Xeroderma pigmentosum group C protein (XPC) and ataxia-telangiectasia mutated related protein (ATR) promote early JNK activation in response to DNA damage and consequently enhance the expression of pol ι, indicating that the novel role of JNK signal pathway is involved in DNA damage response. Furthermore, associated with elevated c-Jun activity, the overexpression of pol ι is positively correlated with the clinical tumor grade in 97 bladder cancer samples and may contribute to the hypermutagenesis. The overexpressed pol ι-involved mutagenesis is dependent on JNK/c-Jun pathway in bladder cancer cells identifying by the special mutation spectra. Our results support the conclusion that dysregulation of pol ι by JNK/c-Jun is involved in carcinogenesis and offer a novel understanding of the role of pol ι or c-Jun in mutagenesis.

Specific effects of c-Jun NH2-terminal kinase-interacting protein 1 in neuronal axons

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Shu Tang

2016-01-01

Full Text Available c-Jun NH2-terminal kinase (JNK-interacting protein 3 plays an important role in brain-derived neurotrophic factor/tropomyosin-related kinase B (TrkB anterograde axonal transport. It remains unclear whether JNK-interacting protein 1 mediates similar effects, or whether JNK-interacting protein 1 affects the regulation of TrkB anterograde axonal transport. In this study, we isolated rat embryonic hippocampus and cultured hippocampal neurons in vitro. Coimmunoprecipitation results demonstrated that JNK-interacting protein 1 formed TrkB complexes in vitro and in vivo. Immunocytochemistry results showed that when JNK-interacting protein 1 was highly expressed, the distribution of TrkB gradually increased in axon terminals. However, the distribution of TrkB reduced in axon terminals after knocking out JNK-interacting protein 1. In addition, there were differences in distribution of TrkB after JNK-interacting protein 1 was knocked out compared with not. However, knockout of JNK-interacting protein 1 did not affect the distribution of TrkB in dendrites. These findings confirm that JNK-interacting protein 1 can interact with TrkB in neuronal cells, and can regulate the transport of TrkB in axons, but not in dendrites.

n-Butyrate inhibits Jun NH(2)-terminal kinase activation and cytokine transcription in mast cells

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Diakos, Christos; Prieschl, Eva E.; Saeemann, Marcus D.; Boehmig, Georg A.; Csonga, Robert; Sobanov, Yury; Baumruker, Thomas; Zlabinger, Gerhard J.

2006-01-01

Mast cells are well known to contribute to type I allergic conditions but only recently have been brought in association with chronic relapsing/remitting autoimmune diseases such as celiac disease and ulcerative colitis. Since the bacterial metabolite n-butyrate is considered to counteract intestinal inflammation we investigated the effects of this short chain fatty acid on mast cell activation. Using RNAse protection assays and reporter gene technology we show that n-butyrate downregulates TNF-α transcription. This correlates with an impaired activation of the Jun NH(2)-terminal kinase (JNK) but not other MAP kinases such as ERK and p38 that are largely unaffected by n-butyrate. As a consequence, we observed a decreased nuclear activity of AP-1 and NF-AT transcription factors. These results indicate that n-butyrate inhibits critical inflammatory mediators in mast cells by relatively selectively targeting the JNK signalling

c-Jun Proto-Oncoprotein Plays a Protective Role in Lung Epithelial Cells Exposed to Staphylococcal α-Toxin

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Alejandro J. Moyano

2018-05-01

Full Text Available c-Jun is a member of the early mammalian transcriptional regulators belonging to the AP-1 family, which participates in a wide range of cellular processes such as proliferation, apoptosis, tumorigenesis, and differentiation. Despite its established role in cell survival upon stress, its participation in the stress response induced by bacterial infections has been poorly investigated. To study the potential role of c-Jun in this context we choose the widely studied α-toxin produced by Staphylococcus aureus, a pore-forming toxin that is a critical virulence factor in the pathogenesis of these bacteria. We analyzed the effect of α-toxin treatment in the activation, expression, and protein levels of c-Jun in A549 lung epithelial cells. Furthermore, we explored the role of c-Jun in the cellular fate after exposure to α-toxin. Our results show that staphylococcal α-toxin per se is able to activate c-Jun by inducing phosphorylation of its Serine 73 residue. Silencing of the JNK (c-Jun N-terminal Kinase signaling pathway abrogated most of this activation. On the contrary, silencing of the ERK (Extracellular Signal-Regulated Kinase pathway exacerbated this response. Intriguingly, while the exposure to α-toxin induced a marked increase in the levels of c-Jun transcripts, c-Jun protein levels noticeably decreased in the same time-frame as a consequence of active proteolytic degradation through the proteasome-dependent pathway. In addition, we established that c-Jun promoted cell survival when cells were challenged with α-toxin. Similarly, c-Jun phosphorylation was also induced in cells upon intoxication with the cytolysin produced by Vibrio cholerae in a JNK-dependent manner, suggesting that c-Jun-JNK axis would be a conserved responsive cellular pathway to pore-forming toxins. This study contributes to understanding the role of the multifaceted c-Jun proto-oncoprotein in cell response to bacterial pore-forming toxins, positioning it as a relevant

Identification of ASK1, MKK4, JNK, c-Jun, and caspase-3 as a signaling cascade involved in cadmium-induced neuronal cell apoptosis

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Kim, Sun Don; Moon, Chang Kyu; Eun, Su-Yong; Ryu, Pan Dong; Jo, Sangmee Ahn

2005-01-01

Cd induces oxidative stress and apoptosis in various cells by activating mitogen-activated protein kinases (MAPKs), but the precise signaling components of the MAPK cascade and their role in neuronal apoptosis are still unclear. Here, we report that Cd treatment of SH-SY5Y cells caused apoptosis through sequential phosphorylation of the apoptosis signal regulating kinase 1, MAPK kinase 4, c-Jun N-terminal kinase (JNK), and c-Jun as determined by overexpression of dominant negative (DN) constructs of these genes or using a specific JNK inhibitor SP600125. Both Cd-induced JNK and c-Jun phosphorylation and apoptosis were inhibited dramatically by N-acetyl-L-cysteine, a free radical scavenger. In addition, caspase inhibitors, zDEVD and zVAD, reduced apoptosis but not JNK and c-Jun phosphorylation induced by Cd, while overexpression of DN JNK1 inhibited caspase-3 activity. Taken together, our data suggested that the JNK/c-Jun signaling cascade plays a crucial role in Cd-induced neuronal cell apoptosis and provides a molecular linkage between oxidative stress and neuronal apoptosis

Bex2 regulates cell proliferation and apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase pathway

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Zhou, Xiuping; Meng, Qingming; Xu, Xuebin; Zhi, Tongle; Shi, Qiong; Wang, Yong; Yu, Rutong

2012-01-01

Highlights: ► The expression levels of Bex2 markedly increased in glioma tissues. ► Bex2 over-expression promoted cell proliferation, while its down-regulation inhibited cell growth. ► Bex2 down-regulation promoted cell apoptosis via JNK/c-Jun signaling pathway. -- Abstract: The function of Bex2, a member of the Brain Expressed X-linked gene family, in glioma is controversial and its mechanism is largely unknown. We report here that Bex2 regulates cell proliferation and apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase (JNK) pathway. The expression level of Bex2 is markedly increased in glioma tissues. We observed that Bex2 over-expression promotes cell proliferation, while down-regulation of Bex2 inhibits cell growth. Furthermore, Bex2 down-regulation promotes cell apoptosis and activates the JNK pathway; these effects were abolished by administration of the JNK specific inhibitor, (SP600125). Thus, Bex2 may be an important player during the development of glioma.

β3-adrenergic receptor activation induces TGFβ1 expression in cardiomyocytes via the PKG/JNK/c-Jun pathway.

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Xu, Zhongcheng; Wu, Jimin; Xin, Junzhou; Feng, Yenan; Hu, Guomin; Shen, Jing; Li, Mingzhe; Zhang, Youyi; Xiao, Han; Wang, Li

2018-06-05

In heart failure, the expression of cardiac β 3 -adrenergic receptors (β 3 -ARs) increases. However, the precise role of β 3 -AR signaling within cardiomyocytes remains unclear. Transforming growth factor β1 (TGFβ1) is a crucial cytokine mediating the cardiac remodeling that plays a causal role in the progression of heart failure. Here, we set out to determine the effect of β 3 -AR activation on TGFβ1 expression in rat cardiomyocytes and examine the underlying mechanism. The selective β 3 -AR agonist BRL37344 induced an increase in TGFβ1 expression and the phosphorylation of c-Jun N-terminal kinase (JNK) and c-Jun in β 3 -AR-overexpressing cardiomyocytes. Those effects of BRL37344 were suppressed by a β 3 -AR antagonist. Moreover, the inhibition of JNK and c-Jun activity by a JNK inhibitor and c-Jun siRNA blocked the increase in TGFβ1 expression upon β 3 -AR activation. A protein kinase G (PKG) inhibitor also attenuated β 3 -AR-agonist-induced TGFβ1 expression and the phosphorylation of JNK and c-Jun. In conclusion, the β 3 -AR activation in cardiomyocytes increases the expression of TGFβ1 via the PKG/JNK/c-Jun pathway. These results help us further understand the role of β 3 -AR signaling in heart failure. Copyright © 2018 Elsevier Inc. All rights reserved.

Cytotoxic Activity of 3,6-Dihydroxyflavone in Human Cervical Cancer Cells and Its Therapeutic Effect on c-Jun N-Terminal Kinase Inhibition

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Eunjung Lee

2014-08-01

Full Text Available Previously we have shown that 3,6-dihydroxyflavone (3,6-DHF is a potent agonist of the human peroxisome proliferator-activated receptor (hPPAR with cytotoxic effects on human cervical cancer cells. To date, the mechanisms by which 3,6-DHF exerts its antitumor effects on cervical cells have not been clearly defined. Here, we demonstrated that 3,6-DHF exhibits a novel antitumor activity against HeLa cells with IC50 values of 25 μM and 9.8 μM after 24 h and 48 h, respectively. We also showed that the anticancer effects of 3,6-DHF are mediated via the toll-like receptor (TLR 4/CD14, p38 mitogen-activated protein kinase (MAPK, Jun-N terminal kinase (JNK, extracellular-signaling regulated kinase (ERK, and cyclooxygenase (COX-2 pathways in lipopolysaccharide (LPS-stimulated RAW264.7 cells. We found that 3,6-DHF showed a similar IC50 (113 nM value to that of the JNK inhibitor, SP600125 (IC50 = 118 nM in a JNK1 kinase assay. Binding studies revealed that 3,6-DHF had a strong binding affinity to JNK1 (1.996 × 105 M−1 and that the 6-OH and the carbonyl oxygen of the C ring of 3,6-DHF participated in hydrogen bonding interactions with the carbonyl oxygen and the amide proton of Met111, respectively. Therefore, 3,6-DHF may be a candidate inhibitor of JNKs, with potent anticancer effects.

Potential role of proteasome on c-jun related signaling in hypercholesterolemia induced atherosclerosis

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Erdi Sozen

2014-01-01

Full Text Available Atherosclerosis and its complications are major causes of death all over the world. One of the major risks of atherosclerosis is hypercholesterolemia. During atherosclerosis, oxidized low density lipoprotein (oxLDL regulates CD36-mediated activation of c-jun amino terminal kinase-1 (JNK1 and modulates matrix metalloproteinase (MMP induction which stimulates inflammation with an invasion of monocytes. Additionally, inhibition of proteasome leads to an accumulation of c-jun and phosphorylated c-jun and activation of activator protein-1 (AP-1 related increase of MMP expression. We have previously reported a significant increase in cluster of differentiation 36 (CD36 mRNA levels in hypercholesterolemic rabbits and shown that vitamin E treatment prevented the cholesterol induced increase in CD36 mRNA expression. In the present study, our aim is to identify the signaling molecules/transcription factors involved in the progression of atherosclerosis following CD36 activation in an in vivo model of hypercholesterolemic (induced by 2% cholesterol containing diet rabbits. In this direction, proteasomal activities by fluorometry and c-jun, phospo c-jun, JNK1, MMP-9 expressions by quantitative RT-PCR and immunoblotting were tested in aortic tissues. The effects of vitamin E on these changes were also investigated in this model. As a result, c-jun was phosphorylated following decreased proteasomal degradation in hypercholesterolemic group. MMP-9 expression was also increased in cholesterol group rabbits contributing to the development of atherosclerosis. In addition, vitamin E showed its effect by decreasing MMP-9 levels and phosphorylation of c-jun.

Inhibition of Vascular c-Jun N-Terminal Kinase 2 Improves Obesity-Induced Endothelial Dysfunction After Roux-en-Y Gastric Bypass.

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Doytcheva, Petia; Bächler, Thomas; Tarasco, Erika; Marzolla, Vincenzo; Engeli, Michael; Pellegrini, Giovanni; Stivala, Simona; Rohrer, Lucia; Tona, Francesco; Camici, Giovanni G; Vanhoutte, Paul M; Matter, Christian M; Lutz, Thomas A; Lüscher, Thomas F; Osto, Elena

2017-11-14

Roux-en-Y gastric bypass (RYGB) reduces obesity-associated comorbidities and cardiovascular mortality. RYGB improves endothelial dysfunction, reducing c-Jun N-terminal kinase (JNK) vascular phosphorylation. JNK activation links obesity with insulin resistance and endothelial dysfunction. Herein, we examined whether JNK1 or JNK2 mediates obesity-induced endothelial dysfunction and if pharmacological JNK inhibition can mimic RYGB vascular benefits. After 7 weeks of a high-fat high-cholesterol diet, obese rats underwent RYGB or sham surgery; sham-operated ad libitum-fed rats received, for 8 days, either the control peptide D-TAT or the JNK peptide inhibitor D-JNKi-1 (20 mg/kg per day subcutaneous). JNK peptide inhibitor D-JNKi-1 treatment improved endothelial vasorelaxation in response to insulin and glucagon-like peptide-1, as observed after RYGB. Obesity increased aortic phosphorylation of JNK2, but not of JNK1. RYGB and JNK peptide inhibitor D-JNKi-1 treatment blunted aortic JNK2 phosphorylation via activation of glucagon-like peptide-1-mediated signaling. The inhibitory phosphorylation of insulin receptor substrate-1 was reduced, whereas the protein kinase B/endothelial NO synthase pathway was increased and oxidative stress was decreased, resulting in improved vascular NO bioavailability. Decreased aortic JNK2 phosphorylation after RYGB rapidly improves obesity-induced endothelial dysfunction. Pharmacological JNK inhibition mimics the endothelial protective effects of RYGB. These findings highlight the therapeutic potential of novel strategies targeting vascular JNK2 against the severe cardiovascular disease associated with obesity. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Low humidity environmental challenge causes barrier disruption and cornification of the mouse corneal epithelium via a c-jun N-terminal kinase 2 (JNK2) pathway.

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Pelegrino, F S A; Pflugfelder, S C; De Paiva, C S

2012-01-01

Patients with tear dysfunction often experience increased irritation symptoms when subjected to drafty and/or low humidity environmental conditions. The purpose of this study was to investigate the effects of low humidity stress (LHS) on corneal barrier function and expression of cornified envelope (CE) precursor proteins in the epithelium of C57BL/6 and c-jun N-terminal kinase 2 (JNK2) knockout (KO) mice. LHS was induced in both strains by exposure to an air draft for 15 (LHS15D) or 30 days (LHS30D) at a relative humidity LHS15D showed corneal barrier dysfunction, decreased apical corneal epithelial cell area, higher MMP-9 expression and gelatinase activity and increased involucrin and SPRR-2 immunoreactivity in the corneal epithelium compared to NS mice. JNK2KO mice were resistant to LHS-induced corneal barrier disruption. MMP-3,-9,-13, IL-1α, IL-1β, involucrin and SPRR-2a RNA transcripts were significantly increased in C57BL/6 mice at LHS15D, while no change was noted in JNK2KO mice. LHS is capable of altering corneal barrier function, promoting pathologic alteration of the TJ complex and stimulating production of CE proteins by the corneal epithelium. Activation of the JNK2 signaling pathway contributes to corneal epithelial barrier disruption in LHS. Copyright © 2011 Elsevier Ltd. All rights reserved.

Phosphorylation of rat brain purified mitochondrial Voltage-Dependent Anion Channel by c-Jun N-terminal kinase-3 modifies open-channel noise.

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Gupta, Rajeev

2017-09-02

The drift kinetic energy of ionic flow through single ion channels cause vibrations of the pore walls which are observed as open-state current fluctuations (open-channel noise) during single-channel recordings. Vibration of the pore wall leads to transitions among different conformational sub-states of the channel protein in the open-state. Open-channel noise analysis can provide important information about the different conformational sub-state transitions and how biochemical modifications of ion channels would affect their transport properties. It has been shown that c-Jun N-terminal kinase-3 (JNK3) becomes activated by phosphorylation in various neurodegenerative diseases and phosphorylates outer mitochondrion associated proteins leading to neuronal apoptosis. In our earlier work, JNK3 has been reported to phosphorylate purified rat brain mitochondrial voltage-dependent anion channel (VDAC) in vitro and modify its conductance and opening probability. In this article we have compared the open-state noise profile of the native and the JNK3 phosphorylated VDAC using Power Spectral Density vs frequency plots. Power spectral density analysis of open-state noise indicated power law with average slope value α ≈1 for native VDAC at both positive and negative voltage whereas average α value open-state noise arises due to coupling of ionic transport and conformational sub-states transitions in open-state and this coupling is perturbed as a result of channel phosphorylation. Copyright © 2017 Elsevier Inc. All rights reserved.

Embryoid body attachment to reconstituted basement membrane induces a genetic program of epithelial differentiation via jun N-terminal kinase signaling.

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Ho, Hoang-Yen; Moffat, Ryan C; Patel, Rupal V; Awah, Franklin N; Baloue, Kaitrin; Crowe, David L

2010-09-01

Embryonic stem (ES) cells are derived from early stage mammalian embryos and have broad developmental potential. These cells can be manipulated experimentally to generate cells of multiple tissue types which could be important in treating human diseases. The ability to produce relevant amounts of these differentiated cell populations creates the basis for clinical interventions in tissue regeneration and repair. Understanding how embryonic stem cells differentiate also can reveal important insights into cell biology. A previously reported mouse embryonic stem cell model demonstrated that differentiated epithelial cells migrated out of embryoid bodies attached to reconstituted basement membrane. We used genomic technology to profile ES cell populations in order to understand the molecular mechanisms leading to epithelial differentiation. Cells with characteristics of cultured epithelium migrated from embryoid bodies attached to reconstituted basement membrane. However, cells that comprised embryoid bodies also rapidly lost ES cell-specific gene expression and expressed proteins characteristic of stratified epithelia within hours of attachment to basement membrane. Gene expression profiling of sorted cell populations revealed upregulation of the BMP/TGFbeta signaling pathway, which was not sufficient for epithelial differentiation in the absence of basement membrane attachment. Activation of c-jun N-terminal kinase 1 (JNK1) and increased expression of Jun family transcription factors was observed during epithelial differentiation of ES cells. Inhibition of JNK signaling completely blocked epithelial differentiation in this model, revealing a key mechanism by which ES cells adopt epithelial characteristics via basement membrane attachment. Copyright (c) 2010 Elsevier B.V. All rights reserved.

A novel dual NO-donating oxime and c-Jun N-terminal kinase inhibitor protects against cerebral ischemia-reperfusion injury in mice.

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Atochin, Dmitriy N; Schepetkin, Igor A; Khlebnikov, Andrei I; Seledtsov, Victor I; Swanson, Helen; Quinn, Mark T; Huang, Paul L

2016-04-08

The c-Jun N-terminal kinase (JNK) has been shown to be an important regulator of neuronal cell death. Previously, we synthesized the sodium salt of 11H-indeno[1,2-b]quinoxalin-11-one (IQ-1S) and demonstrated that it was a high-affinity inhibitor of the JNK family. In the present work, we found that IQ-1S could release nitric oxide (NO) during its enzymatic metabolism by liver microsomes. Moreover, serum nitrite/nitrate concentration in mice increased after intraperitoneal injection of IQ-1S. Because of these dual actions as JNK inhibitor and NO-donor, the therapeutic potential of IQ-1S was evaluated in an animal stroke model. We subjected wild-type C57BL6 mice to focal ischemia (30min) with subsequent reperfusion (48h). Mice were treated with IQ-1S (25mg/kg) suspended in 10% solutol or with vehicle alone 30min before and 24h after middle cerebral artery (MCA) occlusion (MCAO). Using laser-Doppler flowmetry, we monitored cerebral blood flow (CBF) above the MCA during 30min of MCAO provoked by a filament and during the first 30min of subsequent reperfusion. In mice treated with IQ-1S, ischemic and reperfusion values of CBF were not different from vehicle-treated mice. However, IQ-1S treated mice demonstrated markedly reduced neurological deficit and infarct volumes as compared with vehicle-treated mice after 48h of reperfusion. Our results indicate that the novel JNK inhibitor releases NO during its oxidoreductive bioconversion and improves stroke outcome in a mouse model of cerebral reperfusion. We conclude that IQ-1S is a promising dual functional agent for the treatment of cerebral ischemia and reperfusion injury. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

A Novel Dual NO-donating Oxime and c-Jun N-terminal Kinase Inhibitor Protects Against Cerebral Ischemia–Reperfusion Injury in Mice

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Atochin, Dmitriy N.; Schepetkin, Igor A.; Khlebnikov, Andrei I.; Seledtsov, Victor I.; Swanson, Helen; Quinn, Mark T.; Huang, Paul L.

2017-01-01

The c-Jun N-terminal kinase (JNK) has been shown to be an important regulator of neuronal cell death. Previously, we synthesized the sodium salt of 11H-indeno[1,2-b]quinoxalin-11-one (IQ-1S) and demonstrated that it was a high-affinity inhibitor of the JNK family. In the present work, we found that IQ-1S could release nitric oxide (NO) during its enzymatic metabolism by liver microsomes. Moreover, serum nitrite/nitrate concentration in mice increased after intraperitoneal injection of IQ-1S. Because of these dual actions as JNK inhibitor and NO-donor, the therapeutic potential of IQ-1S was evaluated in an animal stroke model. We subjected wild-type C57BL6 mice to focal ischemia (30 minutes) with subsequent reperfusion (48 hours). Mice were treated with IQ-1S (25 mg/kg) suspended in 10% solutol or with vehicle alone 30 minutes before and 24 hours after middle cerebral artery MCA) occlusion (MCAO). Using laser-Doppler flowmetry, we monitored cerebral blood flow (CBF) above the MCA during 30 minutes of MCAO provoked by a filament and during the first 30 minutes of subsequent reperfusion. In mice treated with IQ-1S, ischemic and reperfusion values of CBF were not different from vehicle-treated mice. However, IQ-1S treated mice demonstrated markedly reduced neurological deficit and infarct volumes as compared with vehicle-treated mice after 48 hours of reperfusion. Our results indicate that the novel JNK inhibitor releases NO during its oxidoreductive bioconversion and improves stroke outcome in a mouse model of cerebral reperfusion. We conclude that IQ-1S is a promising dual functional agent for the treatment of cerebral ischemia and reperfusion injury. PMID:26923672

DISCO interacting protein 2 determines direction of axon projection under the regulation of c-Jun N-terminal kinase in the Drosophila mushroom body

International Nuclear Information System (INIS)

Nitta, Yohei; Sugie, Atsushi

2017-01-01

Precisely controlled axon guidance for complex neuronal wiring is essential for appropriate neuronal function. c-Jun N-terminal kinase (JNK) was found to play a role in axon guidance recently as well as in cell proliferation, protection and apoptosis. In spite of many genetic and molecular studies on these biological processes regulated by JNK, how JNK regulates axon guidance accurately has not been fully explained thus far. To address this question, we use the Drosophila mushroom body (MB) as a model since the α/β axons project in two distinct directions. Here we show that DISCO interacting protein 2 (DIP2) is required for the accurate direction of axonal guidance. DIP2 expression is under the regulation of Basket (Bsk), the Drosophila homologue of JNK. We additionally found that the Bsk/DIP2 pathway is independent from the AP-1 transcriptional factor complex pathway, which is directly activated by Bsk. In conclusion, our findings revealed DIP2 as a novel effector downstream of Bsk modulating the direction of axon projection. - Highlights: • DIP2 is required for accurate direction of axon guidance in Drosophila mushroom body. • DIP2 is a downstream of JNK in the axon guidance of Drosophila mushroom body neuron. • JNK/DIP2 pathway is independent from JNK/AP-1 transcriptional factor complex pathway.

Inhibition of spinal astrocytic c-Jun N-terminal kinase (JNK activation correlates with the analgesic effects of ketamine in neuropathic pain

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Wang Wen

2011-01-01

Full Text Available Abstract Background We have previously reported that inhibition of astrocytic activation contributes to the analgesic effects of intrathecal ketamine on spinal nerve ligation (SNL-induced neuropathic pain. However, the underlying mechanisms are still unclear. c-Jun N-terminal kinase (JNK, a member of mitogen-activated protein kinase (MAPK family, has been reported to be critical for spinal astrocytic activation and neuropathic pain development after SNL. Ketamine can decrease lipopolysaccharide (LPS-induced phosphorylated JNK (pJNK expression and could thus exert its anti-inflammatory effect. We hypothesized that inhibition of astrocytic JNK activation might be involved in the suppressive effect of ketamine on SNL-induced spinal astrocytic activation. Methods Immunofluorescence histochemical staining was used to detect SNL-induced spinal pJNK expression and localization. The effects of ketamine on SNL-induced mechanical allodynia were confirmed by behavioral testing. Immunofluorescence histochemistry and Western blot were used to quantify the SNL-induced spinal pJNK expression after ketamine administration. Results The present study showed that SNL induced ipsilateral pJNK up-regulation in astrocytes but not microglia or neurons within the spinal dorsal horn. Intrathecal ketamine relieved SNL-induced mechanical allodynia without interfering with motor performance. Additionally, intrathecal administration of ketamine attenuated SNL-induced spinal astrocytic JNK activation in a dose-dependent manner, but not JNK protein expression. Conclusions The present results suggest that inhibition of JNK activation may be involved in the suppressive effects of ketamine on SNL-induced spinal astrocyte activation. Therefore, inhibition of spinal JNK activation may be involved in the analgesic effects of ketamine on SNL-induced neuropathic pain.

Inhibition of spinal astrocytic c-Jun N-terminal kinase (JNK) activation correlates with the analgesic effects of ketamine in neuropathic pain

Science.gov (United States)

2011-01-01

Background We have previously reported that inhibition of astrocytic activation contributes to the analgesic effects of intrathecal ketamine on spinal nerve ligation (SNL)-induced neuropathic pain. However, the underlying mechanisms are still unclear. c-Jun N-terminal kinase (JNK), a member of mitogen-activated protein kinase (MAPK) family, has been reported to be critical for spinal astrocytic activation and neuropathic pain development after SNL. Ketamine can decrease lipopolysaccharide (LPS)-induced phosphorylated JNK (pJNK) expression and could thus exert its anti-inflammatory effect. We hypothesized that inhibition of astrocytic JNK activation might be involved in the suppressive effect of ketamine on SNL-induced spinal astrocytic activation. Methods Immunofluorescence histochemical staining was used to detect SNL-induced spinal pJNK expression and localization. The effects of ketamine on SNL-induced mechanical allodynia were confirmed by behavioral testing. Immunofluorescence histochemistry and Western blot were used to quantify the SNL-induced spinal pJNK expression after ketamine administration. Results The present study showed that SNL induced ipsilateral pJNK up-regulation in astrocytes but not microglia or neurons within the spinal dorsal horn. Intrathecal ketamine relieved SNL-induced mechanical allodynia without interfering with motor performance. Additionally, intrathecal administration of ketamine attenuated SNL-induced spinal astrocytic JNK activation in a dose-dependent manner, but not JNK protein expression. Conclusions The present results suggest that inhibition of JNK activation may be involved in the suppressive effects of ketamine on SNL-induced spinal astrocyte activation. Therefore, inhibition of spinal JNK activation may be involved in the analgesic effects of ketamine on SNL-induced neuropathic pain. PMID:21255465

Uncaria rhynchophylla and Rhynchophylline inhibit c-Jun N-terminal kinase phosphorylation and nuclear factor-kappaB activity in kainic acid-treated rats.

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Hsieh, Ching-Liang; Ho, Tin-Yun; Su, Shan-Yu; Lo, Wan-Yu; Liu, Chung-Hsiang; Tang, Nou-Ying

2009-01-01

Our previous studies have shown that Uncaria rhynchophylla (UR) can reduce epileptic seizures. We hypothesized that UR and its major component rhynchophylline (RH), reduce epileptic seizures in rats treated with kainic acid (KA) by inhibiting nuclear factor-kappaB (NF-kappaB) and activator-protein-1 (AP-1) activity, and by eliminating superoxide anions. Therefore, the level of superoxide anions and the DNA binding activities of NF-kappaB and AP-1 were measured. Sprague-Dawley (SD) rats were pre-treated with UR (1.0 g/kg, i.p.), RH (0.25 mg/kg, i.p.), or valproic acid (VA, 250 mg/kg, i.p.) for 3 days and then KA was administered intra-peritoneal (i.p.). The results indicated that UR, RH, and VA can reduce epileptic seizures and the level of superoxide anions in the blood. Furthermore, KA was demonstrated to induce the DNA binding activities of NF-kappaB and AP-1. However, these inductions were inhibited by pre-treatment with UR, RH, or VA for 3 days. Moreover, UR and RH were shown to be involved in the suppression of c-Jun N-terminal kinase (JNK) phosphorylation. This study suggested that UR and RH have antiepileptic effects in KA-induced seizures and are associated with the regulation of the innate immune system via a reduction in the level of superoxide anions, JNK phosphorylation, and NF-kappaB activation.

Acute inhibition of central c-Jun N-terminal kinase restores hypothalamic insulin signalling and alleviates glucose intolerance in diabetic mice.

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Benzler, J; Ganjam, G K; Legler, K; Stöhr, S; Krüger, M; Steger, J; Tups, A

2013-05-01

The hypothalamus has been identified as a main insulin target tissue for regulating normal body weight and glucose metabolism. Recent observations suggest that c-Jun-N-terminal kinase (JNK)-signalling plays a crucial role in the development of obesity and insulin resistance because neuronal JNK-1 ablation in the mouse prevented high-fat diet-induced obesity (DIO) and increased energy expenditure, as well as insulin sensitivity. In the present study, we investigated whether central JNK inhibition is associated with sensitisation of hypothalamic insulin signalling in mice fed a high-fat diet for 3 weeks and in leptin-deficient mice. We determined whether i.c.v. injection of a pharmacological JNK-inhibitor (SP600125) improved impaired glucose homeostasis. By immunohistochemistry, we first observed that JNK activity was increased in the arcuate nucleus (ARC) and the ventromedial hypothalamus (VMH) in both mouse models, relative to normoglycaemic controls. This suggests that up-regulation of JNK in these regions is associated with glucose intolerance and obesity, independent of leptin levels. Acute i.c.v. injection of SP600125 ameliorated glucose tolerance within 30 min in both leptin-deficient and DIO mice. Given the acute nature of i.c.v. injections, these effects cannot be attributed to changes in food intake or energy balance. In a hypothalamic cell line, and in the ARC and VMH of leptin-deficient mice, JNK inhibition by SP600125 consistently improved impaired insulin signalling. This was determined by a reduction of phospho-insulin receptor substrate-1 [IRS-1(Ser612)] protein in a hypothalamic cell line and a decline in the number of pIRS-1(Ser612) immunoreactive cells in the ARC and VMH. Serine 612 phosphorylation of IRS-1 is assumed to negatively regulate insulin signalling. In leptin-deficient mice, in both nuclei, central inhibition of JNK increased the number of cells immunoreactive for phospho-Akt (Ser473) and phospho-GSK-3β (Ser9), which are important

Cadmium induces apoptosis in pancreatic β-cells through a mitochondria-dependent pathway: the role of oxidative stress-mediated c-Jun N-terminal kinase activation.

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Kai-Chih Chang

Full Text Available Cadmium (Cd, one of well-known highly toxic environmental and industrial pollutants, causes a number of adverse health effects and diseases in humans. The growing epidemiological studies have suggested a possible link between Cd exposure and diabetes mellitus (DM. However, the toxicological effects and underlying mechanisms of Cd-induced pancreatic β-cell injury are still unknown. In this study, we found that Cd significantly decreased cell viability, and increased sub-G1 hypodiploid cells and annexin V-Cy3 binding in pancreatic β-cell-derived RIN-m5F cells. Cd also increased intracellular reactive oxygen species (ROS generation and malondialdehyde (MDA production and induced mitochondrial dysfunction (the loss of mitochondrial membrane potential (MMP and the increase of cytosolic cytochrome c release, the decreased Bcl-2 expression, increased p53 expression, poly (ADP-ribose polymerase (PARP cleavage, and caspase cascades, which accompanied with intracellular Cd accumulation. Pretreatment with the antioxidant N-acetylcysteine (NAC effectively reversed these Cd-induced events. Furthermore, exposure to Cd induced the phosphorylations of c-jun N-terminal kinases (JNK, extracellular signal-regulated kinases (ERK1/2, and p38-mitogen-activated protein kinase (MAPK, which was prevented by NAC. Additionally, the specific JNK inhibitor SP600125 or JNK-specific small interference RNA (si-RNA transfection suppressed Cd-induced β-cell apoptosis and related signals, but not ERK1/2 and p38-MAPK inhibitors (PD98059 and SB203580 did not. However, the JNK inhibitor or JNK-specific si-RNA did not suppress ROS generation in Cd-treated cells. These results indicate that Cd induces pancreatic β-cell death via an oxidative stress downstream-mediated JNK activation-triggered mitochondria-regulated apoptotic pathway.

Gallic Acid Induces a Reactive Oxygen Species-Provoked c-Jun NH2-Terminal Kinase-Dependent Apoptosis in Lung Fibroblasts

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Chen, Chiu-Yuan; Chen, Kun-Chieh; Yang, Tsung-Ying; Liu, Hsiang-Chun; Hsu, Shih-Lan

2013-01-01

Idiopathic pulmonary fibrosis is a chronic lung disorder characterized by fibroblasts proliferation and extracellular matrix accumulation. Induction of fibroblast apoptosis therefore plays a crucial role in the resolution of this disease. Gallic acid (3,4,5-trihydroxybenzoic acid), a common botanic phenolic compound, has been reported to induce apoptosis in tumor cell lines and renal fibroblasts. The present study was undertaken to examine the role of mitogen-activated protein kinases (MAPKs) in lung fibroblasts apoptosis induced by gallic acid. We found that treatment with gallic acid resulted in activation of c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and protein kinase B (PKB, Akt), but not p38MAPK, in mouse lung fibroblasts. Inhibition of JNK using pharmacologic inhibitor (SP600125) and genetic knockdown (JNK specific siRNA) significantly inhibited p53 accumulation, reduced PUMA and Fas expression, and abolished apoptosis induced by gallic acid. Moreover, treatment with antioxidants (vitamin C, N-acetyl cysteine, and catalase) effectively diminished gallic acid-induced hydrogen peroxide production, JNK and p53 activation, and cell death. These observations imply that gallic acid-mediated hydrogen peroxide formation acts as an initiator of JNK signaling pathways, leading to p53 activation and apoptosis in mouse lung fibroblasts. PMID:23533505

Discovery of novel scaffolds for γ-secretase modulators without an arylimidazole moiety.

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Sekioka, Ryuichi; Honjo, Eriko; Honda, Shugo; Fuji, Hideyoshi; Akashiba, Hiroki; Mitani, Yasuyuki; Yamasaki, Shingo

2018-01-15

Gamma-secretase modulators (GSMs) selectively inhibit the production of amyloid-β 42 (Aβ42) and may therefore be useful in the management of Alzheimer's disease. Most heterocyclic GSMs that are not derived from nonsteroidal anti-inflammatory drugs contain an arylimidazole moiety that potentially inhibits cytochrome P450 (CYP) activity. Here, we discovered imidazopyridine derivatives that represent a new class of scaffold for GSMs, which do not have a strongly basic end group such as arylimidazole. High-throughput screening identified 2-methyl-8-[(2-methylbenzyl)oxy]-3-(pyridin-4-yl)imidazo[1,2-a]pyridine (3a), which inhibited the cellular production of Aβ42 (IC 50  = 7.1 µM) without changing total production of Aβ. Structural optimization of this series of compounds identified 5-[8-(benzyloxy)-2-methylimidazo[1,2-a]pyridin-3-yl]-2-ethylisoindolin-1-one (3m) as a potent inhibitor of Aβ42 (IC 50  = 0.39 µM) but not CYP3A4. Further, 3m demonstrated a sustained pharmacokinetic profile in mice and sufficiently penetrated the brain. Copyright © 2017. Published by Elsevier Ltd.

The role of p38 MAP kinase and c-Jun N-terminal protein kinase signaling in the differentiation and apoptosis of immortalized neural stem cells

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Yang, Se-Ran; Cho, Sung-Dae; Ahn, Nam-Shik; Jung, Ji-Won; Park, Joon-Suk; Jo, Eun-Hye; Hwang, Jae-Woong; Kim, Sung-Hoon; Lee, Bong-Hee; Kang, Kyung-Sun; Lee, Yong-Soon

2005-01-01

The two distinct members of the mitogen-activated protein (MAP) kinase family c-Jun N-terminal protein kinase (JNK) and p38 MAP kinase, play an important role in central nervous system (CNS) development and differentiation. However, their role and functions are not completely understood in CNS. To facilitate in vitro study, we have established an immortal stem cell line using SV40 from fetal rat embryonic day 17. In these cells, MAP kinase inhibitors (SP600125, SB202190, and PD98059) were treated for 1, 24, 48, and 72 h to examine the roles of protein kinases. Early inhibition of JNK did not alter phenotypic or morphological changes of immortalized cells, however overexpression of Bax and decrease of phosphorylated AKT was observed. The prolonged inhibition of JNK induced polyploidization of immortalized cells, and resulted in differentiation and inhibition of cell proliferation. Moreover, JNK and p38 MAP kinase but not ERK1/2 was activated, and p21, p53, and Bax were overexpressed by prolonged inhibition of JNK. These results indicate that JNK and p38 MAP kinase could play dual roles on cell survival and apoptosis. Furthermore, this established cell line could facilitate study of the role of JNK and p38 MAP kinase on CNS development or differentiation/apoptosis

Induction of matrix metalloproteinase-2 by tenascin-X deficiency is mediated through the c-Jun N-terminal kinase and protein tyrosine kinase phosphorylation pathway

International Nuclear Information System (INIS)

Matsumoto, Ken-ichi; Minamitani, Takeharu; Orba, Yasuko; Sato, Mami; Sawa, Hirofumi; Ariga, Hiroyoshi

2004-01-01

The results of our previous study showed that tumor invasion and metastasis are promoted in extracellular matrix (ECM) tenascin-X-deficient (TNX-/-) mice via increased expression of matrix metalloproteinases (MMPs). However, little is known about the relationship between TNX deficiency and activation of MMP genes. In this study, we investigated the molecular mechanism by which TNX deficiency activates the MMP-2 gene. We examined the intracellular signaling pathways that regulate gene expression of the proteinase in isolated fibroblasts. Results of gelatin zymography showed that MMP-2 was induced to a greater extent in TNX-/- fibroblasts embedded in type I collagen than in wild-type fibroblasts. RT-PCR analysis revealed that the increased level of MMP-2 expression was caused at the transcription level. Conversely, stable overexpression of TNX in a fibroblast cell line reduced MMP-2 expression and suppressed MMP-2 promoter activity. In addition, treatment of TNX-/- fibroblasts with SP600125, a c-Jun N-terminal kinase (JNK) inhibitor, and genistein, a tyrosine kinase inhibitor, suppressed the increased level of proMMP-2 and increased MMP-2 promoter activity in TNX-/- fibroblasts. Furthermore, increased activation of JNK and tyrosine phosphorylation of certain proteins were observed in TNX-/- fibroblasts. These findings suggest that induction of MMP-2 by TNX deficiency is mediated, at least in part, through the JNK and protein tyrosine kinase phosphorylation pathway

Acquired tolerance in cadmium-adapted lung epithelial cells: Roles of the c-Jun N-terminal kinase signaling pathway and basal level of metallothionein

International Nuclear Information System (INIS)

Lau, Andy T.Y.; Zhang Jian; Chiu, J.-F.

2006-01-01

Cadmium-resistant cells were developed in our laboratory with rat lung epithelial cells (LECs) by stepwise exposure of LECs to cadmium chloride from 1 μM to 20 μM after 20 passages. To investigate the Cd-resistant phenotype in a long-term perspective, cadmium-resistant cells adapted to 20 μM cadmium (Cd R ) were then cultured in the absence of cadmium for various passages [Cd R (-n)]. All these adapted cells were significantly protected from cadmium toxicity as compared to parental cadmium-sensitive LECs (Cd S ). The cadmium-resistant phenotype of adapted cells was relatively stable in the absence of cadmium for as long as 40 passages. Basal mRNA level of metallothionein-1 (MT-1) was dramatically higher in Cd R than in Cd R (-), which may account for the higher Cd-resistance of Cd R than Cd R (-). MT-1 mRNA level decreased drastically in Cd R after cadmium removal, suggesting that the high basal level of MT-1 in Cd R may be only partially responsible for cadmium-resistance. Treatment of cells with high levels of cadmium resulted in decreased phosphorylation of c-Jun N-terminal kinase (JNK1/2) in adapted cells than in sensitive cells and this cadmium-induced JNK activity was blocked by JNK inhibitor II, SP600125. Ro318220, a strong activator of JNK, reverted cadmium-sensitive phenotype in adapted cells. Taken together, our results suggest that during cadmium adaptation, cells develop tolerance to cell death, generally due to perturbation of the JNK signaling pathway and the nonresponsiveness of JNK phosphorylation is critical for the Cd-tolerance in these cells

BAG3 is upregulated by c-Jun and stabilizes JunD.

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Li, Chao; Li, Si; Kong, De-Hui; Meng, Xin; Zong, Zhi-Hong; Liu, Bao-Qin; Guan, Yifu; Du, Zhen-Xian; Wang, Hua-Qin

2013-12-01

BAG3 plays a regulatory role in a number of cellular processes, including cell proliferation, apoptosis, adhesion and migration, epithelial-mesenchymal transition (EMT), autophagy activation, and virus infection. The AP-1 transcription factors are implicated in a variety of important biological processes including cell differentiation, proliferation, apoptosis and oncogenesis. Recently, it has been reported that AP-1 protein c-Jun inhibits autophagy and enhances apoptotic cell death mediated by starvation. However, the molecular mechanisms remain unclear. For the first time, the current study demonstrated that serum starvation downregulated BAG3 at the transcriptional level via c-Jun. In addition, the current study reported that BAG3 stabilized JunD mRNA, which was, at least in part, responsible for the promotion of serum starvation mediated-growth inhibition by BAG3. © 2013.

Arsenic trioxide inhibits Ewing's sarcoma cell invasiveness by targeting p38(MAPK) and c-Jun N-terminal kinase.

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Zhang, Shuai; Guo, Wei; Ren, Ting-Ting; Lu, Xin-Chang; Tang, Guo-Qing; Zhao, Fu-Long

2012-01-01

Ewing's sarcoma is the second most frequent primary malignant bone tumor, mainly affecting children and young adults. The notorious metastatic capability of this tumor aggravates patient mortality and remains a problem to be overcome. We investigated the effect of arsenic trioxide (As₂O₃) on the metastasis capability of Ewing's sarcoma cells. We performed 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazolium bromide assays to choose appropriate concentrations of As₂O₃ for the experiments. Migration, invasion, and adhesion assays were performed to assess the effect of As₂O₃ on the metastasis of Ewing's sarcoma. Immunofluorescent staining was used to observe cytoskeleton reorganization in Ewing's sarcoma cells treated with As₂O₃. Changes in matrix metalloproteinase-9 expression and the mitogen-activated protein kinase (MAPK) pathway were investigated using western blot. Inhibitors of p38(MAPK) (sb202190) and c-Jun NH₂-terminal kinase (JNK, sp600125) were used in invasion assays to determine the effect of p38(MAPK) and JNK. We found that As₂O₃ may markedly inhibit the migration and invasion capacity of Ewing's sarcoma cells with structural rearrangements of the actin cytoskeleton. The expressions of matrix metalloproteinase-9, phosphor-p38(MAPK), and phosphor-JNK were suppressed by As₂O₃ treatment in a dose-dependent manner. The inhibitors of p38(MAPK) (sb202190) and JNK (sp600125) enhanced the inhibition induced by As₂O₃, which was counteracted by anisomycin, an activating agent of p38(MAPK) and JNK. Taken together, our results demonstrate that As₂O₃ can inhibit the metastasis capability of RD-ES and A-673 cells and may have new therapeutic value for Ewing's sarcoma.

Lower susceptibility of female mice to acetaminophen hepatotoxicity: Role of mitochondrial glutathione, oxidant stress and c-jun N-terminal kinase

International Nuclear Information System (INIS)

Du, Kuo; Williams, C. David; McGill, Mitchell R.; Jaeschke, Hartmut

2014-01-01

Acetaminophen (APAP) overdose causes severe hepatotoxicity in animals and humans. However, the mechanisms underlying the gender differences in susceptibility to APAP overdose in mice have not been clarified. In our study, APAP (300 mg/kg) caused severe liver injury in male mice but 69–77% lower injury in females. No gender difference in metabolic activation of APAP was found. Hepatic glutathione (GSH) was rapidly depleted in both genders, while GSH recovery in female mice was 2.6 fold higher in the mitochondria at 4 h, and 2.5 and 3.3 fold higher in the total liver at 4 h and 6 h, respectively. This faster recovery of GSH, which correlated with greater induction of glutamate-cysteine ligase, attenuated mitochondrial oxidative stress in female mice, as suggested by a lower GSSG/GSH ratio at 6 h (3.8% in males vs. 1.4% in females) and minimal centrilobular nitrotyrosine staining. While c-jun N-terminal kinase (JNK) activation was similar at 2 and 4 h post-APAP, it was 3.1 fold lower at 6 h in female mice. However, female mice were still protected by the JNK inhibitor SP600125. 17β-Estradiol pretreatment moderately decreased liver injury and oxidative stress in male mice without affecting GSH recovery. Conclusion: The lower susceptibility of female mice is achieved by the improved detoxification of reactive oxygen due to accelerated recovery of mitochondrial GSH levels, which attenuates late JNK activation and liver injury. However, even the reduced injury in female mice was still dependent on JNK. While 17β-estradiol partially protects male mice, it does not affect hepatic GSH recovery. - Highlights: • Female mice are less susceptible to acetaminophen overdose than males. • GSH depletion and protein adduct formation are similar in both genders. • Recovery of hepatic GSH levels is faster in females and correlates with Gclc. • Reduced oxidant stress in females leads to reduced JNK activation. • JNK activation and mitochondrial translocation are critical

Heparan sulfate regulates fibrillin-1 N- and C-terminal interactions

DEFF Research Database (Denmark)

Cain, Stuart A; Baldwin, Andrew K; Mahalingam, Yashithra

2008-01-01

Fibrillin-1 N- and C-terminal heparin binding sites have been characterized. An unprocessed monomeric N-terminal fragment (PF1) induced a very high heparin binding response, indicating heparin-mediated multimerization. Using PF1 deletion and short fragments, a heparin binding site was localized w......-terminal interactions with heparin/heparan sulfate directly influence cell behavior, whereas C-terminal interactions with heparin/heparan sulfate regulate elastin deposition. These data highlight how heparin/heparan sulfate controls fibrillin-1 interactions....

[Expression of c-jun protein after experimental rat brain concussion].

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Wang, Feng; Li, Yong-hong

2010-02-01

To observe e-jun protein expression after rat brain concussion and explore the forensic pathologic markers following brain concussion. Fifty-five rats were randomly divided into brain concussion group and control group. The expression of c-jun protein was observed by immunohistochemistry. There were weak positive expression of c-jun protein in control group. In brain concussion group, however, some neutrons showed positive expression of c-jun protein at 15 min after brain concussion, and reach to the peak at 3 h after brain concussion. The research results suggest that detection of c-jun protein could be a marker to determine brain concussion and estimate injury time after brain concussion.

Inhibiting c-Jun N-terminal kinase partially attenuates caffeine-dependent cell death without alleviating the caffeine-induced reduction in mitochondrial respiration in C2C12 skeletal myotubes

International Nuclear Information System (INIS)

Downs, R.M.; Hughes, M.A.; Kinsey, S.T.; Johnson, M.C.; Baumgarner, B.L.

2016-01-01

Caffeine is a widely consumed stimulant that has previously been shown to promote cytotoxic stress and even cell death in numerous mammalian cell lines. Thus far there is little information available regarding the toxicity of caffeine in skeletal muscle cells. Our preliminary data revealed that treating C2C12 myotubes with 5 mM caffeine for 6 h increased nuclear fragmentation and reduced basal and maximal oxygen consumption rate (OCR) in skeletal myotubes. The purpose of this study was to further elucidate the pathways by which caffeine increased cell death and reduced mitochondrial respiration. We specifically examined the role of c-Jun N-terminal kinase (JNK), which has previously been shown to simultaneously increase caspase-dependent cell death and reduce mitochondrial respiration in other mammalian cell lines. We found that caffeine promoted a dose-dependent increase in cell death in multinucleated myotubes but did not in mononucleated myoblasts. The addition of 10 μM Z-DEVD-FMK, a specific inhibitor of executioner caspases, completely inhibited caffeine-dependent cell death. Further, the addition of 400 μM dantrolene, a specific ryanodine receptor (RYR) inhibitor, prevented the caffeine-dependent increase in cell death and the reduction in basal and maximal OCR. We also discovered that caffeine treatment significantly increased the phosphorylation of JNK and that the addition of 30 μM SP600125 (JNKi), a specific JNK inhibitor, partially attenuated caffeine-induced cell death without preventing the caffeine-dependent reduction in basal and maximal OCR. Our results suggest that JNK partially mediates the increase in caspase-dependent cell death but does not contribute to reduced mitochondrial respiration in caffeine-treated skeletal muscle cells. We conclude that caffeine increased cell death and reduced mitochondrial respiration in a calcium-dependent manner by activating the RYR and promoting reticular calcium release. - Highlights: • Caffeine

Niclosamide enhances ROS-mediated cell death through c-Jun activation.

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Lee, Sae-lo-oom; Son, A-Rang; Ahn, Jiyeon; Song, Jie-Young

2014-06-01

Radiotherapy is an effective treatment modality in the clinical treatment of cancers, and has been combined with chemotherapy in order to improve therapeutic efficacy. Therefore, we aimed to develop small molecules that enhance the cytotoxic effects of radiotherapy. In this study, we provide evidence that niclosamide is an effective radiosensitizer in non-small cell lung cancer cells. Using a cell-based high-throughput viability screen of 1040 compounds in combination with γ-ionizing radiation (IR), we found niclosamide, an FDA-approved antihelminthic agent, had a radiosensitizing effect on H1299 human lung cancer cells. Pretreatment with niclosamide enhanced IR- induced cell death of H1299 in a dose-dependent manner via apoptosis compared with IR or niclosamide alone. The combined treatment induced significantly more phosphorylation of p38 MAPK and c-Jun in H1299 cells than IR or niclosamide alone. Since IR induces apoptosis through generation of reactive oxygen species (ROS), hydrogen peroxide (H2O2) was employed as another ROS generator and we found that niclosamide also sensitized cells to H2O2. Niclosamide pretreatment also induced c-Jun and its phosphorylation in the presence of H2O2, thereby enhancing apoptosis. N-acetyl-L-cysteine (NAC) treatment abolished both cell death and c-Jun activation induced by the combination treatments. Knockdown of c-Jun also decreased PARP cleavage and clonogenic cell survival in niclosamide- and IR-treated H1299 cells. Our findings suggest that niclosamide could be a promising radiosensitizer in lung cancer patients through activation of the p38 MAPK-c-Jun axis. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Synthesis of [2-13C, 2-14C] 2-aminoethanol, [1-13C, 1-14C] 2-chloroethylamine, N,N'-bis([1-13C, 1-14C] 2-chloroethyl)-N-nitrosourea(BCNU) and N-([1-13C, 1-14C] 2-chloroethyl)-N-nitrosourea(CNU)

International Nuclear Information System (INIS)

Narayan, R.; Chang, C-j.

1982-01-01

[2- 13 C, 2- 14 C]2-Aminoethanol hydrochloride was prepared in good yield from Na*CN in a two step sequence by first converting the Na*CN to OHCH 2 *CN and then reducing the nitrile directly with a solution of borane-tetrahydrofuran complex. The reaction procedure was simple and the pure product could be obtained readily. Using this specifically labelled precursor, the synthesis of [1- 13 C, 1- 14 C]2-chloroethylamine hydrochloride, N-([1- 13 C, 1- 14 C]2-chloroethyl)-N-nitrosourea(CNU) and N,N'-bis([1- 13 C, 1- 14 C]2-chloroethyl)-N-nitrosourea(BCNU) in good yield without isotope scrambling was also reported. (author)

c-Jun NH2-terminal kinase activity in subcutaneous adipose tissue but not nuclear factor-kappaB activity in peripheral blood mononuclear cells is an independent determinant of insulin resistance in healthy individuals

DEFF Research Database (Denmark)

Sourris, Karly C; Lyons, Jasmine G; de Courten, Maximilian

2009-01-01

Chronic low-grade activation of the immune system (CLAIS) predicts type 2 diabetes via a decrease in insulin sensitivity. Our study investigated potential relationships between nuclear factor-kappaB (NF-kappaB) and c-Jun NH(2)-terminal kinase (JNK) pathways-two pathways proposed as the link between...

[Effect of Acupuncture Intervention on c-jun N-terminal Kinase Signaling in the Hippocampus in Rats with Forced Swimming Stress].

Science.gov (United States)

Guo, Yu; Xu, Ke; Bao, Wu-ye; Wang, Yu; Zhang, Xu-hui; Xu, Ming-min; Yu, Miao; Zhang, Chun-tao; Zhao, Bing-cong; Wu, Ji-hong; Tu, Ya

2016-02-01

To observe the effect of acupuncture on c-jun N-terminal Kinase (JNK) signaling in the hippocampus in rats with forced-swimming stress, so as to reveal its underlying mechanism in relieving depression-like motor response. Forty-eight Sprague-Dawley rats were randomly divided into 8 groups as control, control + JNK inhibitor (SP 600125) , model, model + SP 600125, acupuncture, acupuncture + SP 600125, Fluoxetine (an anti-depressant) , and Fluoxetine + SP 600125 (n = 6 in each group). The depression-like behavior (immobility) model was established by forcing the rat to swim in a glass-cylinder and solitary raise. Acupuncture stimulation was applied to "Baihui" (GV-20) and "Yintang" (GV 29) for 20 min before forced swimming and once again 24 h later.. The rats of the Fluoxetine and Fluoxetine+ SP 600125 groups were treated by intragastric administration of fluoxetine 10 mL (1.8 mg)/kg before forced swimming and once again 24 h thereafter. The rats of the model + SP 600125 and acupuncture + SP 600125 groups were treated by intraperitoneal injection of SP 600125 (10 mg/kg) 90 min before forced swimming and 30 min before acupuncture intervention, respectively. The immobility duration of rats in the water glass-cylinder was used to assess their depression-like behavior response. The expression levels of protein kinase kinase 4 (MKK 4), MKK 7, JNK, and phosphorylated JNK (p-JNK) in the hippocampus were detected by Western blot. Compared to the control group, the duration of immobility, and the expression levels of hippocampal MKK 4, MKK 7, and p-JNK proteins were significantly increased in the model group (P Fluoxetine and Fluoxetine + SP 600125 groups, the expression levels of hippocampal MKK 4 and MKK 7 proteins in the Fluoxetine + SP 600125 group, and those of p-JNK protein in the acupuncture, acupuncture + SP 600125, model + SP 600125, Fluoxetine and Fluoxetine + SP 600125 groups were considerably decreased (P Fluoxetine and Fluoxetine + SP 600125 groups in the

Fos and jun proteins are specifically expressed during differentiation of human keratinocytes.

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Mehic, Denis; Bakiri, Latifa; Ghannadan, Minoo; Wagner, Erwin F; Tschachler, Erwin

2005-01-01

Activator protein 1 (AP-1) proteins play key roles in the regulation of cell proliferation and differentiation. In this study we investigated the expression of Fos and Jun proteins in different models of terminal differentiation of human keratinocytes and in skin from psoriasis patients. All Jun and Fos proteins, with the exception of FosB, were efficiently expressed in keratinocytes in monolayer cultures. In contrast, in normal epidermis as well as in organotypic epidermal cultures, the expression pattern of AP-1 proteins was dependent on the differentiation stage. Fos proteins were readily detected in nuclei of keratinocytes of basal and suprabasal layers. JunB and JunD were expressed in all layers of normal epidermis. Interestingly, expression of c-Jun started suprabasally, then disappeared and became detectable again in distinct cells of the outermost granular layer directly at the transition zone to the stratum corneum. In psoriatic epidermis, c-Jun expression was prominent in both hyperproliferating basal and suprabasal keratinocytes, whereas c-Fos expression was unchanged. These data indicate that AP-1 proteins are expressed in a highly specific manner during terminal differentiation of keratinocytes and that the enhanced expression of c-Jun in basal and suprabasal keratinocytes might contribute to the pathogenesis of psoriasis.

catena-Poly[[bis[[bis(3-aminopropylamine-κ3N,N′,N′′](thiocyanato-κNcadmium]-μ4-sulfato-κ4O,O:O′,O′] methanol hemisolvate

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Jan Boeckmann

2011-09-01

Full Text Available The asymmetric unit of the title compound, {[Cd2(NCS2(SO4(C6H17N32]·0.5CH3OH}n, consists of two Cd2+ cations, two thiocyanate and one sulfate anion, two bis(3-aminopropylamine co-ligands and one methanol molecule with half-occupancy. Each Cd2+ cation is coordinated by four N atoms of one terminal N-bonded thiocyanate anion and one bis(3-aminopropylamine co-ligand, and by two O atoms of two symmetry-related sulfate anions, defining a slightly distorted octahedral coordination polyhedron. Each two Cd2+ cations are connected into dimers, which are located on centres of inversion and which are further μ-1,1:3,3-bridged via the sulfate anions into polymeric zigzag chains along the a axis.

The Green Tea Component (--Epigallocatechin-3-Gallate Sensitizes Primary Endothelial Cells to Arsenite-Induced Apoptosis by Decreasing c-Jun N-Terminal Kinase-Mediated Catalase Activity.

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Jee-Youn Kim

Full Text Available The green tea component (--epigallocatechin-3-gallate (EGCG has been shown to sensitize many different types of cancer cells to anticancer drug-induced apoptosis, although it protects against non-cancerous primary cells against toxicity from certain conditions such as exposure to arsenic (As or ultraviolet irradiation. Here, we found that EGCG promotes As-induced toxicity of primary-cultured bovine aortic endothelial cells (BAEC at doses in which treatment with each chemical alone had no such effect. Increased cell toxicity was accompanied by an increased condensed chromatin pattern and fragmented nuclei, cleaved poly(ADP-ribose polymerase (PARP, activity of the pro-apoptotic enzymes caspases 3, 8 and 9, and Bax translocation into mitochondria, suggesting the involvement of an apoptotic signaling pathway. Fluorescence activated cell sorting analysis revealed that compared with EGCG or As alone, combined EGCG and As (EGCG/As treatment significantly induced production of reactive oxygen species (ROS, which was accompanied by decreased catalase activity and increased lipid peroxidation. Pretreatment with N-acetyl-L-cysteine or catalase reversed EGCG/As-induced caspase activation and EC toxicity. EGCG/As also increased the phosphorylation of c-Jun N-terminal kinase (JNK, which was not reversed by catalase. However, pretreatment with the JNK inhibitor SP600125 reversed all of the observed effects of EGCG/As, suggesting that JNK may be the most upstream protein examined in this study. Finally, we also found that all the observed effects by EGCG/As are true for other types of EC tested. In conclusion, this is firstly to show that EGCG sensitizes non-cancerous EC to As-induced toxicity through ROS-mediated apoptosis, which was attributed at least in part to a JNK-activated decrease in catalase activity.

The Green Tea Component (-)-Epigallocatechin-3-Gallate Sensitizes Primary Endothelial Cells to Arsenite-Induced Apoptosis by Decreasing c-Jun N-Terminal Kinase-Mediated Catalase Activity.

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Kim, Jee-Youn; Choi, Ji-Young; Lee, Hyeon-Ju; Byun, Catherine Jeonghae; Park, Jung-Hyun; Park, Jae Hoon; Cho, Ho-Seong; Cho, Sung-Jin; Jo, Sangmee Ahn; Jo, Inho

2015-01-01

The green tea component (-)-epigallocatechin-3-gallate (EGCG) has been shown to sensitize many different types of cancer cells to anticancer drug-induced apoptosis, although it protects against non-cancerous primary cells against toxicity from certain conditions such as exposure to arsenic (As) or ultraviolet irradiation. Here, we found that EGCG promotes As-induced toxicity of primary-cultured bovine aortic endothelial cells (BAEC) at doses in which treatment with each chemical alone had no such effect. Increased cell toxicity was accompanied by an increased condensed chromatin pattern and fragmented nuclei, cleaved poly(ADP-ribose) polymerase (PARP), activity of the pro-apoptotic enzymes caspases 3, 8 and 9, and Bax translocation into mitochondria, suggesting the involvement of an apoptotic signaling pathway. Fluorescence activated cell sorting analysis revealed that compared with EGCG or As alone, combined EGCG and As (EGCG/As) treatment significantly induced production of reactive oxygen species (ROS), which was accompanied by decreased catalase activity and increased lipid peroxidation. Pretreatment with N-acetyl-L-cysteine or catalase reversed EGCG/As-induced caspase activation and EC toxicity. EGCG/As also increased the phosphorylation of c-Jun N-terminal kinase (JNK), which was not reversed by catalase. However, pretreatment with the JNK inhibitor SP600125 reversed all of the observed effects of EGCG/As, suggesting that JNK may be the most upstream protein examined in this study. Finally, we also found that all the observed effects by EGCG/As are true for other types of EC tested. In conclusion, this is firstly to show that EGCG sensitizes non-cancerous EC to As-induced toxicity through ROS-mediated apoptosis, which was attributed at least in part to a JNK-activated decrease in catalase activity.

Hyperoside Downregulates the Receptor for Advanced Glycation End Products (RAGE and Promotes Proliferation in ECV304 Cells via the c-Jun N-Terminal Kinases (JNK Pathway Following Stimulation by Advanced Glycation End-Products In Vitro

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Zhengyu Zhang

2013-11-01

Full Text Available Hyperoside is a major active constituent in many medicinal plants which are traditionally used in Chinese medicines for their neuroprotective, anti-inflammatory and antioxidative effects. The molecular mechanisms underlying these effects are unknown. In this study, quiescent ECV304 cells were treated in vitro with advanced glycation end products (AGEs in the presence or absence of hyperoside. The results demonstrated that AGEs induced c-Jun N-terminal kinases (JNK activation and apoptosis in ECV304 cells. Hyperoside inhibited these effects and promoted ECV304 cell proliferation. Furthermore, hyperoside significantly inhibited RAGE expression in AGE-stimulated ECV304 cells, whereas knockdown of RAGE inhibited AGE-induced JNK activation. These results suggested that AGEs may promote JNK activation, leading to viability inhibition of ECV304 cells via the RAGE signaling pathway. These effects could be inhibited by hyperoside. Our findings suggest a novel role for hyperoside in the treatment and prevention of diabetes.

Reactive oxygen species activate differentiation gene transcription of acute myeloid leukemia cells via the JNK/c-JUN signaling pathway.

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Lam, Chung Fan; Yeung, Hoi Ting; Lam, Yuk Man; Ng, Ray Kit

2018-05-01

Reactive oxygen species (ROS) and altered cellular redox status are associated with many malignancies. Acute myeloid leukemia (AML) cells are maintained at immature state by differentiation blockade, which involves deregulation of transcription factors in myeloid differentiation. AML cells can be induced to differentiate by phorbol-12-myristate-13-acetate (PMA), which possesses pro-oxidative activity. However, the signaling events mediated by ROS in the activation of transcriptional program during AML differentiation has not been fully elucidated. Here, we investigated AML cell differentiation by treatment with PMA and ROS scavenger N-acetyl-l-cysteine (NAC). We observed elevation of intracellular ROS level in the PMA-treated AML cells, which correlated with differentiated cell morphology and increased CD11b + mature cell population. The effect of PMA can be abolished by NAC co-treatment, supporting the involvement of ROS in the process. Moreover, we demonstrated that short ROS elevation mediated cell cycle arrest, but failed to activate myeloid gene transcription; whereas prolonged ROS elevation activated JNK/c-JUN signaling pathway. Inhibition of JNK suppressed the expression of key myeloid transcriptional regulators c-JUN, SPI-1 and MAFB, and prevented AML cells from undergoing terminal differentiation. These findings provide new insights into the crucial role of JNK/c-Jun signaling pathway in the activation of transcriptional program during ROS-mediated AML differentiation. Copyright © 2018 Elsevier Ltd. All rights reserved.

Design and synthesis of the first generation of novel potent, selective, and in vivo active (benzothiazol-2-yl)acetonitrile inhibitors of the c-Jun N-terminal kinase.

Science.gov (United States)

Gaillard, Pascale; Jeanclaude-Etter, Isabelle; Ardissone, Vittoria; Arkinstall, Steve; Cambet, Yves; Camps, Montserrat; Chabert, Christian; Church, Dennis; Cirillo, Rocco; Gretener, Denise; Halazy, Serge; Nichols, Anthony; Szyndralewiez, Cedric; Vitte, Pierre-Alain; Gotteland, Jean-Pierre

2005-07-14

Several lines of evidence support the hypothesis that c-Jun N-terminal kinase (JNKs) plays a critical role in a wide range of diseases including cell death (apoptosis)-related disorders (neurodegenerative diseases, brain, heart, and renal ischemia, epilepsy) and inflammatory disorders (multiple sclerosis, rheumatoid arthritis, inflammatory bowel diseases). Screening of our internal compound collection for inhibitors of JNK3 led to the identification of (benzothiazol-2-yl)acetonitrile derivatives as potent and selective JNK1, -2, -3 inhibitors. Starting from initial hit 1 (AS007149), the chemistry and initial structure-activity relationship (SAR) of this novel and unique kinase inhibitor template were explored. Investigation of the SAR rapidly revealed that the benzothiazol-2-ylacetonitrile pyrimidine core was crucial to retain a good level of potency on rat JNK3. Therefore, compound 6 was further optimized by exploring a number of distal combinations in place of the chlorine atom. This led to the observation that the presence of an aromatic group, two carbons away from the aminopyrimidine moiety and bearing substituents conferring hydrogen bond acceptor (HBA) properties, could improve the potency. Further improvements to the biological and biopharmaceutical profile of the most promising compounds were performed, resulting in the discovery of compound 59 (AS601245). The in vitro and in vivo anti-inflammatory potential of this new JNK inhibitor was investigated and found to demonstrate efficacy per oral route in an experimental model of rheumatoid arthritis (RA).

Synthesis and structure of unprecedented samarium complex with bulky bis-iminopyrrolyl ligand via intramolecular C=N bond activation

Energy Technology Data Exchange (ETDEWEB)

Das, Suman; Anga, Srinivas; Harinath, Adimulam; Panda, Tarun K. [Department of Chemistry, Indian Institute of Technology, Hyderabad (India); Pada Nayek, Hari [Department of Applied Chemistry, Indian Institute of Technology, (ISM) Dhanbad, Jharkhand (India)

2017-12-29

An unprecedentate samarium complex of the molecular composition [{κ"3-{(Ph_2CH)N=CH}{sub 2}C{sub 4}H{sub 2}N}{κ"3-{(Ph_2CHN=CH)(Ph_2CHNCH)C_4H_2N}Sm}{sub 2}] (2), which was isolated by the reaction of a potassium salt of 2,5-bis{N-(diphenylmethyl)-iminomethyl}pyrrolyl ligand [K(THF){sub 2}{(Ph_2CH)N=CH}{sub 2}C{sub 4}H{sub 2}N] (1) with anhydrous samarium diiodide in THF at 60 C through the in situ reduction of imine bond is presented. The homoleptic samarium complex [[κ{sup 3}-{(Ph_2CH)-N=CH}{sub 2}C{sub 4}H{sub 2}N]{sub 3}Sm] (3) can also be obtained from the reaction of compound 1 with anhydrous samarium triiodide (SmI{sub 3}) in THF at 60 C. The molecular structures of complexes 2 and 3 were established by single-crystal X-ray diffraction analysis. The molecular structure of complex 2 reveals the formation of a C-C bond in the 2,5-bis{N-(diphenylmethyl)iminomethyl}pyrrole ligand moiety (Ph{sub 2}Py{sup -}). However, complex 3 is a homoleptic samarium complex of three bis-iminopyrrolyl ligands. In complex 2, the samarium ion adopts an octahedral arrangement, whereas in complex 3, a distorted three face-centered trigonal prismatic mode of nine coordination is observed around the metal ion. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

N-Terminal Domains in Two-Domain Proteins Are Biased to Be Shorter and Predicted to Fold Faster Than Their C-Terminal Counterparts

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Etai Jacob

2013-04-01

Full Text Available Computational analysis of proteomes in all kingdoms of life reveals a strong tendency for N-terminal domains in two-domain proteins to have shorter sequences than their neighboring C-terminal domains. Given that folding rates are affected by chain length, we asked whether the tendency for N-terminal domains to be shorter than their neighboring C-terminal domains reflects selection for faster-folding N-terminal domains. Calculations of absolute contact order, another predictor of folding rate, provide additional evidence that N-terminal domains tend to fold faster than their neighboring C-terminal domains. A possible explanation for this bias, which is more pronounced in prokaryotes than in eukaryotes, is that faster folding of N-terminal domains reduces the risk for protein aggregation during folding by preventing formation of nonnative interdomain interactions. This explanation is supported by our finding that two-domain proteins with a shorter N-terminal domain are much more abundant than those with a shorter C-terminal domain.

Marcadores fenotípicos de atenuación en cepas de virus Junín recuperadas de individuos vacunados con la cepa Junín Candid#1

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Graciela S. Gamboa

2013-08-01

Full Text Available La Fiebre Hemorrágica Argentina es una enfermedad producida por el virus Junín. Para la prevención de esta enfermedad se obtuvo una vacuna efectiva denominada Candid#1. Durante un ensayo clínico realizado en el INEVH, dos cepas de virus Junín fueron aisladas de sangre periférica de dos voluntarios mediante co-cultivo de células mononucleares. El objetivo de este trabajo fue comparar las características fenotípicas de atenuación de esas dos cepas recuperadas de humanos con las de la vacuna Candid#1 utilizando los indicadores de atenuación desarrollados por Contigiani y Sabattini en 1977. A tal fin se midieron los índices de letalidad, infección y protección en cobayos y ratones de diferentes edades. Las tres cepas investigadas resultaron letales para ratones recién nacidos pero no para ratones de 10 a 12 días, ratones adultos ni cobayos, aun a la más baja dilución inoculada. Los cobayos inoculados con las cepas recuperadas de humanos y con la cepa Candid#1 no presentaron síntomas de enfermedad y mostraron estar protegidos cuando fueron desafiados con una cepa patógena. Los índices de infección y de protección hallados indican que estas cepas poseen elevada capacidad infectante y protectora en las especies animales aquí estudiadas. Estos resultados demuestran que las cepas de virus Junín aisladas de voluntarios inmunizados con Candid#1 mantienen el mismo fenotipo atenuado de la vacuna Candid#1 después de un pasaje por humanos.

Bis[N,N-bis(1-allyl-1H-benzimidazol-2-ylmethyl-κN3benzylamine-κN]cadmium dipicrate

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Jing-Kun Yuan

2011-06-01

Full Text Available The crystal structure of the title compound, [Cd(C29H29N52](C6H2N3O72, consists of CdII complex cations and picrate anions. In the complex cation, the CdII ion is chelated by two bis(1-allylbenzimidazol-2-ylmethylbenzylamine (babb ligands in a distorted octahedral geometry. Extensive C—H...O hydrogen bonding occurs between cations and anions in the crystal structure.

Ischemic preconditioning negatively regulates plenty of SH3s-mixed lineage kinase 3-Rac1 complex and c-Jun N-terminal kinase 3 signaling via activation of Akt.

Science.gov (United States)

Zhang, Q-G; Han, D; Xu, J; Lv, Q; Wang, R; Yin, X-H; Xu, T-L; Zhang, G-Y

2006-12-01

Activation of Akt/protein kinase B has been recently reported to play an important role in ischemic tolerance. We here demonstrate that the decreased protein expression and phosphorylation of phosphatase and tensin homolog deleted from chromosome 10 (PTEN) underlie the increased Akt-Ser-473 phosphorylation in the hippocampal CA1 subfield in ischemic preconditioning (IPC). Co-immunoprecipitation analysis reveals that Akt physically interacts with Rac1, a small Rho family GTPase required for mixed lineage kinase 3 (MLK3) autophosphorylation, and both this interaction and Rac1-Ser-71 phosphorylation induced by Akt are promoted in preconditioned rats. In addition, we show that Akt activation results in the disassembly of the plenty of SH3s (POSH)-MLK3-Rac1 signaling complex and down-regulation of the activation of MLK3/c-Jun N-terminal kinase (JNK) pathway. Akt activation results in decreased serine phosphorylation of 14-3-3, a cytoplasmic anchor of Bax, and prevents ischemia-induced mitochondrial translocation of Bax, release of cytochrome c, and activation of caspase-3. The expression of Fas ligand is also decreased in the CA1 region. Akt activation protects against apoptotic neuronal death as shown in TUNEL staining following IPC. Intracerebral infusion of LY294002 before IPC reverses the increase in Akt phosphorylation and the decrease in JNK signaling activation, as well as the neuroprotective action of IPC. Our results suggest that activation of pro-apoptotic MLK3/JNK3 cascade can be suppressed through activating anti-apoptotic phosphoinositide 3-kinase/Akt pathway induced by a sublethal ischemic insult, which provides a functional link between Akt and the JNK family of stress-activated kinases in ischemic tolerance.

Overexpression of c-Jun contributes to sorafenib resistance in human hepatoma cell lines.

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Yuki Haga

Full Text Available Despite recent advances in treatment strategies, it is still difficult to cure patients with hepatocellular carcinoma (HCC. Sorafenib is the only approved multiple kinase inhibitor for systemic chemotherapy in patients with advanced HCC. The majority of advanced HCC patients are resistant to sorafenib. The mechanisms of sorafenib resistance are still unknown.The expression of molecules involved in the mitogen-activated protein kinase (MAPK signaling pathway in human hepatoma cell lines was examined in the presence or absence of sorafenib. Apoptosis of human hepatoma cells treated with sorafenib was investigated, and the expression of Jun proto-oncogene (c-Jun was measured.The expression and phosphorylation of c-Jun were enhanced in human hepatoma cell lines after treatment with sorafenib. Inhibiting c-Jun enhanced sorafenib-induced apoptosis. The overexpression of c-Jun impaired sorafenib-induced apoptosis. The expression of osteopontin, one of the established AP-1 target genes, was enhanced after treatment with sorafenib in human hepatoma cell lines.The protein c-Jun plays a role in sorafenib resistance in human hepatoma cell lines. The modulation and phosphorylation of c-Jun could be a new therapeutic option for enhancing responsiveness to sorafenib. Modulating c-Jun may be useful for certain HCC patients with sorafenib resistance.

Critical role of c-Jun overexpression in liver metastasis of human breast cancer xenograft model

International Nuclear Information System (INIS)

Zhang, Yan; Hu, Meiru; Shen, Beifen; Guo, Ning; Pu, Xiaoyun; Shi, Ming; Chen, Liyong; Song, Yuhua; Qian, Lu; Yuan, Guogang; Zhang, Hao; Yu, Ming

2007-01-01

c-Jun/AP-1 has been linked to invasive properties of aggressive breast cancer. Recently, it has been reported that overexpression of c-Jun in breast cancer cell line MCF-7 resulted in increased AP-1 activity, motility and invasiveness of the cells in vitro and tumor formation in nude mice. However, the role of c-Jun in metastasis of human breast cancer in vivo is currently unknown. To further investigate the direct involvement of c-Jun in tumorigenesis and metastasis, in the present study, the effects of c-Jun overexpression were studied in both in vitro and in nude mice. Ectopic overexpression of c-Jun promoted the growth of MCF-7 cells and resulted in a significant increase in the percentage of cells in S phase and increased motility and invasiveness. Introduction of c-Jun gene alone into weakly invasive MCF-7 cells resulted in the transfected cells capable of metastasizing to the nude mouse liver following tail vein injection. The present study confirms that overexpression of c-Jun contributes to a more invasive phenotype in MCF-7 cells. It indicates an interesting relationship between c-Jun expression and increased property of adhesion, migration and in vivo liver metastasis of MCF-7/c-Jun cells. The results provide further evidence that c-Jun is involved in the metastasis of breast cancer. The finding also opens an opportunity for development of anti-c-Jun strategies in breast cancer therapy

Neuroprotection by inhibiting the c-Jun N-terminal kinase pathway after cerebral ischemia occurs independently of interleukin-6 and keratinocyte-derived chemokine (KC/CXCL1 secretion

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Benakis Corinne

2012-04-01

Full Text Available Abstract Background Cerebral ischemia is associated with the activation of glial cells, infiltration of leukocytes and an increase in inflammatory mediators in the ischemic brain and systemic circulation. How this inflammatory response influences lesion size and neurological outcome remains unclear. D-JNKI1, an inhibitor of the c-Jun N-terminal kinase pathway, is strongly neuroprotective in animal models of stroke. Intriguingly, the protection mediated by D-JNKI1 is high even with intravenous administration at very low doses with undetectable drug levels in the brain, pointing to a systemic mode of action, perhaps on inflammation. Findings We evaluated whether D-JNKI1, administered intravenously 3 h after the onset of middle cerebral artery occlusion (MCAO, modulates secretion of the inflammatory mediators interleukin-6 and keratinocyte-derived chemokine in the plasma and from the spleen and brain at several time points after MCAO. We found an early release of both mediators in the systemic circulation followed by an increase in the brain and went on to show a later systemic increase in vehicle-treated mice. Release of interleukin-6 and keratinocyte-derived chemokine from the spleen of mice with MCAO was not significantly different from sham mice. Interestingly, the secretion of these inflammatory mediators was not altered in the systemic circulation or brain after successful neuroprotection with D-JNKI1. Conclusions We demonstrate that neuroprotection with D-JNKI1 after experimental cerebral ischemia is independent of systemic and brain release of interleukin-6 and keratinocyte-derived chemokine. Furthermore, our findings suggest that the early systemic release of interleukin-6 and keratinocyte-derived chemokine may not necessarily predict an unfavorable outcome in this model.

Bis[2,6-bis(trimethylsilylaminopyridine-κN1]{[6-bis(trimethylsilylaminopyridin-2-yl-κN1](trimethylsilylazanido-κN}lithium

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Justin A. Rave

2016-03-01

Full Text Available The title complex, [Li(C11H22N3Si2(C11H23N3Si22], contains a single lithium cation coordinated to three ligands. This is the first reported example of the ligand 2,6-bis(trimethylsilylaminopyridine supporting a monometallic complex. One ligand is mono-anionic and forms a four-membered chelate ring with the lithium cation via the pyridine and silylamido N atoms. The other two ligands are neutral and bind via the pyridine nitrogen. The lithium cation is coordinated in a tetrahedral environment. No intra- or intermolecular hydrogen bonding is observed in the crystal structure, likely indicating that weak electrostatic interactions are the dominant feature of the crystal packing.

N-terminally truncated POM121C inhibits HIV-1 replication.

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Hideki Saito

Full Text Available Recent studies have identified host cell factors that regulate early stages of HIV-1 infection including viral cDNA synthesis and orientation of the HIV-1 capsid (CA core toward the nuclear envelope, but it remains unclear how viral DNA is imported through the nuclear pore and guided to the host chromosomal DNA. Here, we demonstrate that N-terminally truncated POM121C, a component of the nuclear pore complex, blocks HIV-1 infection. This truncated protein is predominantly localized in the cytoplasm, does not bind to CA, does not affect viral cDNA synthesis, reduces the formation of 2-LTR and diminished the amount of integrated proviral DNA. Studies with an HIV-1-murine leukemia virus (MLV chimeric virus carrying the MLV-derived Gag revealed that Gag is a determinant of this inhibition. Intriguingly, mutational studies have revealed that the blockade by N-terminally-truncated POM121C is closely linked to its binding to importin-β/karyopherin subunit beta 1 (KPNB1. These results indicate that N-terminally-truncated POM121C inhibits HIV-1 infection after completion of reverse transcription and before integration, and suggest an important role for KPNB1 in HIV-1 replication.

Tissue-specific deletion of c-Jun in the pancreas has limited effects on pancreas formation

International Nuclear Information System (INIS)

Yamamoto, Kaoru; Miyatsuka, Takeshi; Tanaka, Ayako; Toyoda, Shuichi; Kato, Ken; Shiraiwa, Toshihiko; Fujitani, Yoshio; Yamasaki, Yoshimitsu; Hori, Masatsugu; Matsuhisa, Munehide; Matsuoka, Taka-aki; Kaneto, Hideaki

2007-01-01

It is well known that activating protein-1 (AP-1) is involved in a variety of cellular functions such as proliferation, differentiation, apoptosis, and oncogenesis. AP-1 is a dimer complex consisting of different subunits, and c-Jun is known to be one of its major components. In addition, it has been shown that mice lacking c-Jun are embryonic lethal and that c-Jun is essential for liver and heart development. However, the role of c-Jun in the pancreas is not well known. The aim of this study was to examine the possible role of c-Jun in the pancreas. First, c-Jun was strongly expressed in pancreatic duct-like structures at an embryonic stage, while a lower level of expression was observed in some part of the adult pancreas, implying that c-Jun might play a role during pancreas development. Second, to address this point, we generated pancreas-specific c-Jun knock-out mice (Ptf1a-Cre; c-Jun flox/flox mice) by crossing Ptf1a-Cre knock-in mice with c-Jun floxed mice. Ptf1a is a pancreatic transcription factor and its expression is confined to pancreatic stem/progenitor cells, which give rise to all three types of pancreatic tissue: endocrine, exocrine, and duct. Contrary to our expectation, however, there was no morphological difference in the pancreas between Ptf1a-Cre; c-Jun flox/flox and control mice. In addition, there was no difference in body weight, pancreas weight, and the expression of various pancreas-related factors (insulin, glucagon, cytokeratin, and amylase) between the two groups. Furthermore, there was no difference in glucose tolerance between Ptf1a-Cre; c-Jun flox/flox and control mice. Taken together, although we cannot exclude the possibility that c-Jun ablation is compensated by some unknown factors, c-Jun appears to be dispensable for pancreas development at least after ptf1a gene promoter is activated

Inhibition of transcriptional activity of c-JUN by SIRT1

International Nuclear Information System (INIS)

Gao Zhanguo; Ye Jianping

2008-01-01

c-JUN is a major component of heterodimer transcription factor AP-1 (Activator Protein-1) that activates gene transcription in cell proliferation, inflammation and stress responses. SIRT1 (Sirtuin 1) is a histone deacetylase that controls gene transcription through modification of chromatin structure. However, it is not clear if SIRT1 regulates c-JUN activity in the control of gene transcription. Here, we show that SIRT1 associated with c-JUN in co-immunoprecipitation of whole cell lysate, and inhibited the transcriptional activity of c-JUN in the mammalian two hybridization system. SIRT1 was found in the AP-1 response element in the matrix metalloproteinase-9 (MMP9) promoter DNA leading to inhibition of histone 3 acetylation as shown in a ChIP assay. The SIRT1 signal was reduced by the AP-1 activator PMA, and induced by the SIRT1 activator Resveratrol in the promoter DNA. SIRT1-mediaetd inhibition of AP-1 was demonstrated in the MMP9 gene expression at the gene promoter, mRNA and protein levels. In mouse embryonic fibroblast (MEF) with SIRT1 deficiency (SIRT1 -/- ), mRNA and protein of MMP9 were increased in the basal condition, and the inhibitory activity of Resveratrol was significantly attenuated. Glucose-induced MMP9 expression was also inhibited by SIRT1 in response to Resveratrol. These data consistently suggest that SIRT1 directly inhibits the transcriptional activity of AP-1 by targeting c-JUN

A Convenient Approach to Synthesizing Peptide C-Terminal N-Alkyl Amides

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Fang, Wei-Jie; Yakovleva, Tatyana; Aldrich, Jane V.

2014-01-01

Peptide C-terminal N-alkyl amides have gained more attention over the past decade due to their biological properties, including improved pharmacokinetic and pharmacodynamic profiles. However, the synthesis of this type of peptide on solid phase by current available methods can be challenging. Here we report a convenient method to synthesize peptide C-terminal N-alkyl amides using the well-known Fukuyama N-alkylation reaction on a standard resin commonly used for the synthesis of peptide C-terminal primary amides, the PAL-PEG-PS (Peptide Amide Linker-polyethylene glycol-polystyrene) resin. The alkylation and oNBS deprotection were conducted under basic conditions and were therefore compatible with this acid labile resin. The alkylation reaction was very efficient on this resin with a number of different alkyl iodides or bromides, and the synthesis of model enkephalin N-alkyl amide analogs using this method gave consistently high yields and purities, demonstrating the applicability of this methodology. The synthesis of N-alkyl amides was more difficult on a Rink amide resin, especially the coupling of the first amino acid to the N-alkyl amine, resulting in lower yields for loading the first amino acid onto the resin. This method can be widely applied in the synthesis of peptide N-alkyl amides. PMID:22252422

Anti-Inflammatory Effects and Joint Protection in Collagen-Induced Arthritis after Treatment with IQ-1S, a Selective c-Jun N-Terminal Kinase Inhibitor.

Science.gov (United States)

Schepetkin, Igor A; Kirpotina, Liliya N; Hammaker, Deepa; Kochetkova, Irina; Khlebnikov, Andrei I; Lyakhov, Sergey A; Firestein, Gary S; Quinn, Mark T

2015-06-01

c-Jun N-terminal kinases (JNKs) participate in many physiologic and pathologic processes, including inflammatory diseases. We recently synthesized the sodium salt of IQ-1S (11H-indeno[1,2-b]quinoxalin-11-one oxime) and demonstrated that it is a high-affinity JNK inhibitor and inhibits murine delayed-type hypersensitivity. Here we show that IQ-1S is highly specific for JNK and that its neutral form is the most abundant species at physiologic pH. Molecular docking of the IQ-1S syn isomer into the JNK1 binding site gave the best pose, which corresponded to the position of cocrystallized JNK inhibitor SP600125 (1,9-pyrazoloanthrone). Evaluation of the therapeutic potential of IQ-1S showed that it inhibited matrix metalloproteinase 1 and 3 gene expression induced by interleukin-1β in human fibroblast-like synoviocytes and significantly attenuated development of murine collagen-induced arthritis (CIA). Treatment with IQ-1S either before or after induction of CIA resulted in decreased clinical scores, and joint sections from IQ-1S-treated CIA mice exhibited only mild signs of inflammation and minimal cartilage loss compared with those from control mice. Collagen II-specific antibody responses were also reduced by IQ-1S treatment. By contrast, the inactive ketone derivative 11H-indeno[1,2-b]quinoxalin-11-one had no effect on CIA clinical scores or collagen II-specific antibody titers. IQ-1S treatment also suppressed proinflammatory cytokine and chemokine levels in joints and lymph node cells. Finally, treatment with IQ-1S increased the number of Foxp3(+)CD4(+)CD25(+) regulatory T cells in lymph nodes. Thus, IQ-1S can reduce inflammation and cartilage loss associated with CIA and can serve as a small-molecule modulator for mechanistic studies of JNK function in rheumatoid arthritis. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

E/Z-Photoisomerization of N,N'-Bis(4-dimethylaminobenzylidene1,2-diaminoethane and N,N'-Bis(4-dimethylaminobenzylidene1,3-diaminopropane in Chloroform

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Asghar Samimi

2011-01-01

Full Text Available The E/Z-Photoisomerization of Schiff bases N,N'-bis(4-dimethylamino benzylidene1,2-diaminoethane (BDAE and N,N'-bis(4-dimethylaminobenzyli-dene1,3-diaminopropane (BDAP were studied by UV-Vis absorption spectroscopy and theoretical chemistry calculations. Photochemical investigations in solution depict the time resolved spectral changes, recorded before and after irradiation. The shift indicates the transformation from E to Z configuration of the C=N bond in solution for BDAE and BDAP. Spectra profiles and kinetic constants were evaluated using multivariate curve resolution and non-linear least squares curve fitting by toolbox of MATLAB program using the corresponding absorption spectra-time data. The experimental results show that BDAP can perform the photochromism easier than BDAE, may be due to the molecular topology difference.

Versatile deprotonated NHC: C,N-bridged dinuclear iridium and rhodium complexes

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Albert Poater

2016-01-01

Full Text Available Bearing the versatility of N-heterocyclic carbene (NHC ligands, here density functional theory (DFT calculations unravel the capacity of coordination of a deprotonated NHC ligand (pNHC to generate a doubly C2,N3-bridged dinuclear complex. Here, in particular the discussion is based on the combination of the deprotonated 1-arylimidazol (aryl = mesityl (Mes with [M(cod(μ-Cl] (M = Ir, Rh generated two geometrical isomers of complex [M(cod{µ-C3H2N2(Mes-κC2,κN3}]2. The latter two isomers display conformations head-to-head (H-H and head-to-tail (H-T of CS and C2 symmetry, respectively. The isomerization from the H-H to the H-T conformation is feasible, whereas next substitutions of the cod ligand by CO first, and PMe3 later confirm the H-T coordination as the thermodynamically preferred. It is envisaged the exchange of the metal, from iridium to rhodium, confirming here the innocence of the nature of the metal for such arrangements of the bridging ligands.

Molecular mechanisms involved in cochlear implantation trauma and the protection of hearing and auditory sensory cells by inhibition of c-Jun-N-terminal kinase signaling.

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Eshraghi, Adrien A; Gupta, Chhavi; Van De Water, Thomas R; Bohorquez, Jorge E; Garnham, Carolyn; Bas, Esperanza; Talamo, Victoria Maria

2013-03-01

To investigate the molecular mechanisms involved in electrode insertion trauma (EIT) and to test the otoprotective effect of locally delivered AM-111. An animal model of cochlear implantation. Guinea pigs' hearing thresholds were measured by auditory brainstem response (ABR) before and after cochlear implantation in four groups: EIT; pretreated with hyaluronate gel 30 minutes before EIT (EIT+Gel); pretreated with hyaluronate gel/AM-111 30 minutes before EIT (EIT+AM-111); and unoperated contralateral ears as controls. Neurofilament, synapsin, and fluorescein isothiocyanate (FITC)-phalloidin staining for hair cell counts were performed at 90 days post-EIT. Immunostaining for 4-hydroxy-2-nonenal (HNE), activated caspase-3, CellROX, and phospho-c-Jun were performed at 24 hours post-EIT. ABR thresholds increased post-EIT in the cochleae of EIT only and EIT+Gel treated animals. There was no significant increase in hearing thresholds in cochleae from either EIT+AM-111 treated or unoperated control ears. AM-111 protection of organ of Corti sensory elements (i.e., hair cells [HCs], supporting cells [SCs], nerve fibers, and synapses) was documented at 3 months post-EIT. Immunostaining of 24-hour post-EIT specimens demonstrated increased levels of HNE in HCs and SCs; increased levels of CellROX and activation of caspase-3 was observed only in SCs, and phosphorylation of c-Jun occurred only in HCs of the EIT-only and EIT+Gel specimens. There was no immunostaining for either HNE, CellROX, caspase-3, or phospho-c-Jun in the organ of Corti specimens from AM-111 treated cochleae. Molecular mechanisms involved in programmed cell death of HCs are different than the ones involved in programmed cell death of SCs. Local delivery of AM-111 provided a significant level of protection against EIT-induced hearing losses, HC losses, and damage to neural elements. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

Puerarin reduces apoptosis in rat hippocampal neurons culturea in high glucose medium by modulating the p38 mitogen activated protein kinase and c-Jun N-terminal kinase signaling pathways.

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Xu, Xiaohan; Wang, Jingbo; Zhang, Hong; Tian, Guoqing; Liu, Yuqin

2016-02-01

To investigate the neuroprotective etfect of puerarin on rat hippocampal neurons cultured in high glucose medium, and to examine the role of the p38 mitogen activated protein kinase (p38 MAPK) and c-Jun N-terminal kinase (JNK) signaling pathways in this effect. Primary cultures of hippocampal neurons were prepared from newborn Sprague Dawley rats. Neuron-specific enolase immunocytochemistry was used to identify neurons. The neurons were cultured with normal medium (control group) or with high-glucose medium (high-glucose group), and puerarin (puerarin group), a p38 MAPK inhibitor (SB239063; p38 MAPK inhibitor group) or a JNK inhibitor (SP600125; JNK inhibitor group) were added. After 72 h of treatment, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay was performed to detect apoptosis, and western blotting was used to assess protein levels of p-p38, p38, p-JNK and JNK. In the high-glucose group, the neuronal apoptosis rate and the p-p38/p38 and p-JNK/JNK ratios were higher than in the control group. The p38 MAPK and JNK inhibitors prevented this increase in the apoptosis rate. The apoptosis rates in the puerarin group, the p38 MAPK inhibitor group and the JNK inhibitor group were significantly decreased compared with the high-glucose group. Moreover, protein levels of p-p38 and p-JNK were significantly reduced, and the p-p38/p38 and p-JNK/JNK ratios were decreased in the puerarin group compared with the high-glucose group. In addition, compared with the high-glucose group, p-p38 levels and the p-p38/p38 ratio were reduced in the p38 MAPK inhibitor group, and p-JNK levels and the p-JNK/JNK ratio were decreased in the JNK inhibitor group. Puerarin attenuates neuronal apoptosis induced by high glucose by reducing the phosphorylation of p38 and JNK.

Adsorption kinetics of c-Fos and c-Jun to air-water interfaces.

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Del Boca, Maximiliano; Nobre, Thatyane Morimoto; Zaniquelli, Maria Elisabete Darbello; Maggio, Bruno; Borioli, Graciela A

2007-11-01

The kinetics of adsorption to air-water interfaces of the biomembrane active transcription factors c-Fos, c-Jun and their mixtures is investigated. The adsorption process shows three distinct stages: a lag time, a fast pseudo zero-order stage, and a halting stage. The initial stage determines the course of the process, which is concentration dependent until the end of the fast stage. We show that c-Fos has faster adsorption kinetics than c-Jun over all three stages and that the interaction between both proteins is apparent in the adsorption profiles of the mixtures. Protein molecular reorganization at the interface determines the transition to the final adsorption stage of the pure proteins as well as that of the mixtures.

C,C'-bis(benzodiazaborolyl)dicarba-closo-dodecaboranes: synthesis, structures, photophysics and electrochemistry.

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Weber, Lothar; Kahlert, Jan; Brockhinke, Regina; Böhling, Lena; Halama, Johannes; Brockhinke, Andreas; Stammler, Hans-Georg; Neumann, Beate; Nervi, Carlo; Harder, Rachel A; Fox, Mark A

2013-08-14

Six new C,C'-bis(benzodiazaborolyl)dicarba-closo-dodecaboranes, 1,A-R2-1,A-C2B10H10, where R represents the group 2-(1,3-Et2-1,3,2-N2BC6H4) or 2-(1,3-Ph2-1,3,2-N2BC6H4) and A is 2, 7 or 12, were synthesized from o-, m-, and p-dicarbadodecaboranes (carboranes) by lithiation and subsequent treatment with the respective 2-bromo-1,3,2-benzodiazaboroles. UV-visible and fluorescence spectra of all carboranes display low energy charge transfer emissions. While such emissions with Stokes shifts between 17,330 and 21,290 cm(-1) are typical for C,C'-bis(aryl)-ortho-carboranes, the observed low-energy emissions with Stokes shifts between 8320 and 15,170 cm(-1) for the meta- and para-isomers are unusual as high-energy emissions are typical for meta- and para-dicarbadodecaboranes. Fluorescence quantum yields (φF) for the novel 1,7- and 1,12-bis(benzodiazaborolyl)-carboranes depend on the substituents at the nitrogen atoms of the heterocycle. Thus, the para-carborane with N-ethyl substituents 1,12-(1',3'-Et2-1',3',2'-N2BC6H4)2-1,12-C2B10H10 has a φF value of 41% in cyclohexane solution and only of 9% in the solid state, whereas the analogous 1,12-(1',3'-Ph2-1',3',2'-N2BC6H4)2-1,12-C2B10H10 shows quantum yields of 3% in cyclohexane solution and 72% in the solid state. X-ray crystallographic, computational and cyclic voltammetry studies for these carboranes are also presented.

Heterogeneity in c-jun gene expression in normal and malignant cells exposed to either ionizing radiation or hydrogen peroxide

International Nuclear Information System (INIS)

Horio, M.; Collart, F.R.; Huberman, E.

1993-01-01

We investigated the role of reactive oxygen intermediates and protein kinase C (PKC) in induction of c-jun gene expression in human ML-2 leukemic cells and normal DET-551 fibroblasts by comparing the effects of either ionizing radiation or H 2 O 2 exposure in the presence or absence of appropriate inhibitors. In these cell types, the radiation and H 2 O 2 -mediated increase in c-jun mRNA levels could be prevented by pretreatment of the cells with N-acetylcysteine, an antioxidant, or H7, an inhibitor of PKC and cAMP-dependent protein kinase (PKA), but not by HA1004, an inhibitor of PKA. These results suggest a role for PKC and reactive oxygen intermediates in the induction of c-jun gene expression in both normal and tumor cells. We also investigated potential differences in radiation- or H 2 O 2 -induced c-jun gene expression in normal and tumor cells by examining steady-state c-jun mRNA levels in a number of human fibroblast, leukemia, melanoma, sarcoma, and carcinoma cell types. We observed heterogeneity in the steady-state level of c-jun mRNA in both the untreated normal and tumor cells and in such cells exposed to ionizing radiation or to H 2 O 2 . Exposure to radiation or to hydrogen peroxide produced a varied response which ranged from little or no induction to a more than two orders of magnitude increase in the steady-state level of the c-jun mRNA

Activation of JNK and c-Jun is involved in glucose oxidase-mediated cell death of human lymphoma cells.

Science.gov (United States)

Son, Young-Ok; Jang, Yong-Suk; Shi, Xianglin; Lee, Jeong-Chae

2009-12-31

Mitogen-activated protein kinases (MAPK) affect the activation of activator protein-1 (AP-1), which plays an important role in regulating a range of cellular processes. However, the roles of these signaling factors on hydrogen peroxide (H(2)O(2))-induced cell death are unclear. This study examined the effects of H(2)O(2) on the activation of MAPK and AP-1 by exposing the cells to H(2)O(2) generated by either glucose oxidase or a bolus addition. Exposing BJAB or Jurkat cells to H(2)O(2) affected the activities of MAPK differently according to the method of H(2)O(2) exposure. H(2)O(2) increased the AP-1-DNA binding activity in these cells, where continuously generated H(2)O(2) led to an increase in mainly the c-Fos, FosB and c-Jun proteins. The c-Jun-NH(2)-terminal kinase (JNK)-mediated activation of c-Jun was shown to be related to the H(2)O(2)-induced cell death. However, the suppression of H(2)O(2)-induced oxidative stress by either JNK inhibitor or c-Jun specific antisense transfection was temporary in the cells exposed to glucose oxidase but not to a bolus H(2)O(2). This was associated with the disruption of death signaling according to the severe and prolonged depletion of reduced glutathione. Overall, these results suggest that H(2)O(2) may decide differently the mode of cell death by affecting the intracellular redox state of thiol-containing antioxidants, and this depends more closely on the duration exposed to H(2)O(2) than the concentration of this agent.

c-Jun induces apoptosis of starved BM2 monoblasts by activating cyclin A-CDK2

International Nuclear Information System (INIS)

Vanhara, Petr; Bryja, Vitezslav; Horvath, Viktor; Kozubik, Alois; Hampl, Ales; Smarda, Jan

2007-01-01

c-Jun is one of the major components of the activating protein-1 (AP-1), the transcription factor that participates in regulation of proliferation, differentiation, and apoptosis. In this study, we explored functional interactions of the c-Jun protein with several regulators of the G1/S transition in serum-deprived v-myb-transformed chicken monoblasts BM2. We show that the c-Jun protein induces expression of cyclin A, thus up-regulating activity of cyclin A-associated cyclin-dependent kinase 2 (CDK2), and causing massive programmed cell death of starved BM2cJUN cells. Specific inhibition of CDK2 suppresses frequency of apoptosis of BM2cJUN cells. We conclude that up-regulation of cyclin A expression and CDK2 activity can represent important link between the c-Jun protein, cell cycle machinery, and programmed cell death pathway in leukemic cells

Distribution and habitat description of Junín Rail Laterallus tuerosi, Andean Peru

DEFF Research Database (Denmark)

Dinesen, Lars; Chamorro, Alan; Fjeldså, Jon

2017-01-01

Distribution and habitat description of the endangered Junín Rail Laterallus tuerosi were assessed during a field study between 6 and 20 February 2014 in the marshes surrounding Lake Junín in the high Andes of Peru, which is the only known locality for the species. By using point counts and playb......Distribution and habitat description of the endangered Junín Rail Laterallus tuerosi were assessed during a field study between 6 and 20 February 2014 in the marshes surrounding Lake Junín in the high Andes of Peru, which is the only known locality for the species. By using point counts...

Di-tert-butyl N-[2,6-bis(methoxymethoxyphenyl]iminodiacetate

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Ben Capuano

2009-04-01

Full Text Available The title molecule, C20H31NO8, has pseudo-C2 symmetry about the C—N bond, with the bis(tert-butoxycarbonylamino group twisted from the benzene ring plane by ca 60° and the bulky tert-butoxycarbonyl (Boc groups are orientated away from the substituted aniline group. As part of an antibacterial drug discovery programme furnishing analogues of platensimycin, we unexpectedly synthesized the bis-Boc-protected aniline.

Acetylation within the N- and C-Terminal Domains of Src Regulates Distinct Roles of STAT3-Mediated Tumorigenesis.

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Huang, Chao; Zhang, Zhe; Chen, Lihan; Lee, Hank W; Ayrapetov, Marina K; Zhao, Ting C; Hao, Yimei; Gao, Jinsong; Yang, Chunzhang; Mehta, Gautam U; Zhuang, Zhengping; Zhang, Xiaoren; Hu, Guohong; Chin, Y Eugene

2018-06-01

Posttranslational modifications of mammalian c-Src N-terminal and C-terminal domains regulate distinct functions. Myristoylation of G 2 controls its cell membrane association and phosphorylation of Y419/Y527 controls its activation or inactivation, respectively. We provide evidence that Src-cell membrane association-dissociation and catalytic activation-inactivation are both regulated by acetylation. In EGF-treated cells, CREB binding protein (CBP) acetylates an N-terminal lysine cluster (K5, K7, and K9) of c-Src to promote dissociation from the cell membrane. CBP also acetylates the C-terminal K401, K423, and K427 of c-Src to activate intrinsic kinase activity for STAT3 recruitment and activation. N-terminal domain phosphorylation (Y14, Y45, and Y68) of STAT3 by c-Src activates transcriptionally active dimers of STAT3. Moreover, acetyl-Src translocates into nuclei, where it forms the Src-STAT3 enhanceosome for gene regulation and cancer cell proliferation. Thus, c-Src acetylation in the N-terminal and C-terminal domains play distinct roles in Src activity and regulation. Significance: CBP-mediated acetylation of lysine clusters in both the N-terminal and C-terminal regions of c-Src provides additional levels of control over STAT3 transcriptional activity. Cancer Res; 78(11); 2825-38. ©2018 AACR . ©2018 American Association for Cancer Research.

C-Jun expression in lichen planus, psoriasis, and cutaneous squamous cell carcinoma, an immunohistochemical study.

Science.gov (United States)

Abdou, Asmaa Gaber; Marae, Alaa Hassan; Shoeib, Mohammed; Dawood, Ghada; Abouelfath, Enas

2018-01-01

The AP-1 transcription factor complex is a key player in regulating inflammatory processes, cell proliferation, differentiation, and cell transformation. The aim of the present study is to investigate C-Jun (one of AP-1complex) expression and its proliferative role in skin samples of lichen planus, psoriasis as common inflammatory skin diseases and squamous cell carcinoma using immunohistochemical method. The present study was carried out on skin biopsies of 15 psoriatic patients, 15 lichen planus patients, 15 SCC, and 15 normal skin biopsies. Nuclear expression of C-Jun was detected in basal and few suprabasal layers of epidermis of normal skin. C-Jun was expressed in the whole epidermal layers of both psoriasis (14/15) and lichen planus (15/15) in addition to its expression in lymphocytic infiltrate in the latter in about half of cases (8/15). C-Jun was also expressed in 93.3% (14/15) of SCC in a percentage lower than that of psoriasis, lichen planus, and normal skin. The percentage of C-Jun expression in SCC was significantly associated with an early stage (p = 0.000), free surgical margins (p = 0.022), and small tumour size (p = 0.003). The marked reduction of C-Jun in SCC in comparison to normal skin and inflammatory skin dermatoses may refer to its tumour suppressor activity. C-Jun expression in SCC carries favourable prognosis. Absence of significant association between C-Jun and Ki-67 either in SCC or inflammatory skin diseases indicates that it does not affect proliferative capacity of cells.

Rapid and preferential activation of the c-jun gene during the mammalian UV response

International Nuclear Information System (INIS)

Devary, Y.; Gottlieb, R.A.; Lau, L.F.; Karin, M.

1991-01-01

Exposure of mammalian cells to DNA-damaging agents leads to activation of a genetic response known as the UV response. Because several previously identified UV-inducible genes contain AP-1 binding sites within their promoters, we investigated the induction of AP-1 activity by DNA-damaging agents. We found that expression of both c-jun and c-fos, which encode proteins that participate in formation of the AP-1 complex, is rapidly induced by two different DNA-damaging agents: UV and H2O2. Interestingly, the c-jun gene is far more responsive to UV than any other immediate-early gene that was examined, including c-fos. Other jun and fos genes were only marginally affected by UV or H2O2. Furthermore, UV is a much more efficient inducer of c-jun than phorbol esters, the standard inducers of c-jun expression. This preferential response of the c-jun gene is mediated by its 5' control region and requires the TPA response element, suggesting that this element also serves as an early target for the signal transduction pathway elicited by DNA damage. Both UV and H2O2 lead to a long-lasting increase in AP-1 binding activity, suggesting that AP-1 may mediate the induction of other damage-inducible genes such as human collagenase

Tidbits for the synthesis of bis(2-sulfanylethyl)amido (SEA) polystyrene resin, SEA peptides and peptide thioesters.

Science.gov (United States)

Ollivier, Nathalie; Raibaut, Laurent; Blanpain, Annick; Desmet, Rémi; Dheur, Julien; Mhidia, Reda; Boll, Emmanuelle; Drobecq, Hervé; Pira, Silvain L; Melnyk, Oleg

2014-02-01

Protein total chemical synthesis enables the atom-by-atom control of the protein structure and therefore has a great potential for studying protein function. Native chemical ligation of C-terminal peptide thioesters with N-terminal cysteinyl peptides and related methodologies are central to the field of protein total synthesis. Consequently, methods enabling the facile synthesis of peptide thioesters using Fmoc-SPPS are of great value. Herein, we provide a detailed protocol for the preparation of bis(2-sulfanylethyl)amino polystyrene resin as a starting point for the synthesis of C-terminal bis(2-sulfanylethyl)amido peptides and of peptide thioesters derived from 3-mercaptopropionic acid. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.

Stabilization of N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)benzidine thin film morphology with UV light

Energy Technology Data Exchange (ETDEWEB)

Tomović, A.Ž.; Markešević, N. [Institute of Physics, University of Belgrade, Pregrevica 118, 11000 Belgrade (Serbia); Scarpellini, M.; Bovio, S. [Interdisciplinary Centre for Nanostructured Materials and Interfaces (CIMAINA), Università di Milano, Via Celoria 16, 20133 Milan (Italy); Lucenti, E. [Interdisciplinary Centre for Nanostructured Materials and Interfaces (CIMAINA), Università di Milano, Via Celoria 16, 20133 Milan (Italy); Institute of Molecular Science and Technology of CNR, via Golgi 19, 20133 Milan (Italy); Milani, P. [Interdisciplinary Centre for Nanostructured Materials and Interfaces (CIMAINA), Università di Milano, Via Celoria 16, 20133 Milan (Italy); Zikic, R. [Institute of Physics, University of Belgrade, Pregrevica 118, 11000 Belgrade (Serbia); Jovanović, V.P., E-mail: vladimir.jovanovic@ipb.ac.rs [Institute of Physics, University of Belgrade, Pregrevica 118, 11000 Belgrade (Serbia); Srdanov, V.I. [Interdisciplinary Centre for Nanostructured Materials and Interfaces (CIMAINA), Università di Milano, Via Celoria 16, 20133 Milan (Italy)

2014-07-01

Owing to their low glass transition temperature, T{sub g}, amorphous thin films of N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)benzidine (TPD) undergo morphological changes even at room temperature. It has been noticed previously that exposure to UV light can increase apparent T{sub g} of TPD films and thus stabilize their morphology. However, the reason behind increase in structural stability was not examined at the time. Here we present evidence that TPD molecules undergo photo-oxidation in air when exposed to λ ≈ 350 nm radiation and that less than 5% of the photo-oxidized species are needed to prevent dewetting of thin TPD films. We propose that photo-oxidized TPD species bind strongly to both ordinary TPD molecules and to terminal hydroxyl groups at the substrate surface, which decreases mobility of TPD molecules and makes thin TPD film less prone to morphology changes. - Highlights: • We made variable thickness TPD films and exposed them to UV light under ambient conditions. • Mass spectroscopy and proton NMR measurements of irradiated and pristine TPD films • TPD molecules undergo oxidation process under UV light irradiation. • Dipole–dipole interactions may be responsible for stabilization of morphological changes.

N-Boc amines to oxazolidinones via Pd(II)/bis-sulfoxide/Brønsted acid co-catalyzed allylic C-H oxidation.

Science.gov (United States)

Osberger, Thomas J; White, M Christina

2014-08-06

A Pd(II)/bis-sulfoxide/Brønsted acid catalyzed allylic C-H oxidation reaction for the synthesis of oxazolidinones from simple N-Boc amines is reported. A range of oxazolidinones are furnished in good yields (avg 63%) and excellent diastereoselectivities (avg 15:1) to furnish products regioisomeric from those previously obtained using allylic C-H amination reactions. Mechanistic studies suggest the role of the phosphoric acid is to furnish a Pd(II)bis-sulfoxide phosphate catalyst that promotes allylic C-H cleavage and π-allylPd functionalization with a weak, aprotic oxygen nucleophile and to assist in catalyst regeneration.

Monosodium Urate in the Presence of RANKL Promotes Osteoclast Formation through Activation of c-Jun N-Terminal Kinase

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Jung-Yoon Choe

2015-01-01

Full Text Available The aim of this study was to clarify the role of monosodium urate (MSU crystals in receptor activator of nuclear factor kB ligand- (RANKL- RANK-induced osteoclast formation. RAW 264.7 murine macrophage cells were incubated with MSU crystals or RANKL and differentiated into osteoclast-like cells as confirmed by staining for tartrate-resistant acid phosphatase (TRAP and actin ring, pit formation assay, and TRAP activity assay. MSU crystals in the presence of RANKL augmented osteoclast differentiation, with enhanced mRNA expression of NFATc1, cathepsin K, carbonic anhydrase II, and matrix metalloproteinase-9 (MMP-9, in comparison to RAW 264.7 macrophages incubated in the presence of RANKL alone. Treatment with both MSU crystals and RANKL induced osteoclast differentiation by activating downstream molecules in the RANKL-RANK pathway including tumor necrosis factor receptor-associated factor 6 (TRAF-6, JNK, c-Jun, and NFATc1. IL-1b produced in response to treatment with both MSU and RANKL is involved in osteoclast differentiation in part through the induction of TRAF-6 downstream of the IL-1b pathway. This study revealed that MSU crystals contribute to enhanced osteoclast formation through activation of RANKL-mediated pathways and recruitment of IL-1b. These findings suggest that MSU crystals might be a pathologic causative agent of bone destruction in gout.

Graded Elevation of c-Jun in Schwann Cells In Vivo: Gene Dosage Determines Effects on Development, Remyelination, Tumorigenesis, and Hypomyelination.

Science.gov (United States)

Fazal, Shaline V; Gomez-Sanchez, Jose A; Wagstaff, Laura J; Musner, Nicolo; Otto, Georg; Janz, Martin; Mirsky, Rhona; Jessen, Kristján R

2017-12-13

Schwann cell c-Jun is implicated in adaptive and maladaptive functions in peripheral nerves. In injured nerves, this transcription factor promotes the repair Schwann cell phenotype and regeneration and promotes Schwann-cell-mediated neurotrophic support in models of peripheral neuropathies. However, c-Jun is associated with tumor formation in some systems, potentially suppresses myelin genes, and has been implicated in demyelinating neuropathies. To clarify these issues and to determine how c-Jun levels determine its function, we have generated c-Jun OE/+ and c-Jun OE/OE mice with graded expression of c-Jun in Schwann cells and examined these lines during development, in adulthood, and after injury using RNA sequencing analysis, quantitative electron microscopic morphometry, Western blotting, and functional tests. Schwann cells are remarkably tolerant of elevated c-Jun because the nerves of c-Jun OE/+ mice, in which c-Jun is elevated ∼6-fold, are normal with the exception of modestly reduced myelin thickness. The stronger elevation of c-Jun in c-Jun OE/OE mice is, however, sufficient to induce significant hypomyelination pathology, implicating c-Jun as a potential player in demyelinating neuropathies. The tumor suppressor P19 ARF is strongly activated in the nerves of these mice and, even in aged c-Jun OE/OE mice, there is no evidence of tumors. This is consistent with the fact that tumors do not form in injured nerves, although they contain proliferating Schwann cells with strikingly elevated c-Jun. Furthermore, in crushed nerves of c-Jun OE/+ mice, where c-Jun levels are overexpressed sufficiently to accelerate axonal regeneration, myelination and function are restored after injury. SIGNIFICANCE STATEMENT In injured and diseased nerves, the transcription factor c-Jun in Schwann cells is elevated and variously implicated in controlling beneficial or adverse functions, including trophic Schwann cell support for neurons, promotion of regeneration, tumorigenesis

Synthesis, structurale elucidation and antioxidant study of Ortho-substituted N,N’-bis(benzamidothiocarbonyl)hydrazine derivatives

Science.gov (United States)

Firdausiah, Syadza; Hasbullah, S. A.; Yamin, B. M.

2018-03-01

Some bis(thiourea) compounds have been reported to posses excellent performance in pharmaceutical and environmental fields because of their ability to form chelating complexes with various anions and metal ions. Structurally for carbonyl thiourea derivatives, to become a chelating agent, it must adopt cis-configuration. In the present study, four new bis(thiourea) derivatives namely N,N’-bis(o-fluorobenzamidothiocarbonyl)hydrazine (1), N,N’- bis(o-chloro-benzamidothiocarbonyl)hydrazine (2), N,N’-bis(o-nitrobenzamidothiocarbonyl)-hydrazine (3), and N,N’-bis(o-methylbenzamidothiocarbonyl)hydrazine (4) were successfully synthesized and characterized by CHNS microelemental analysis, FTIR, UV-Vis, and 1H and 13C NMR spectroscopy. However chemical crystallography study showed that both thiourea moieties in compound (2) and (3) adopt trans geometry. Therefore they are potential monodentate ligand with two active moieties. DPPH radical scavenging experiment showed that compound (1), (2), and (4) exhibited higher antioxidant activity than ascorbic acid (Vitamin C).

c-Jun controls the efficiency of MAP kinase signaling by transcriptional repression of MAP kinase phosphatases

International Nuclear Information System (INIS)

Sprowles, Amy; Robinson, Dan; Wu Yimi; Kung, H.-J.; Wisdom, Ron

2005-01-01

The mammalian JNK signaling pathway regulates the transcriptional response of cells to environmental stress, including UV irradiation. This signaling pathway is composed of a classical MAP kinase cascade; activation results in phosphorylation of the transcription factor substrates c-Jun and ATF2, and leads to changes in gene expression. The defining components of this pathway are conserved in the fission yeast S. pombe, where the genetic studies have shown that the ability of the JNK homolog Spc1 to be activated in response to UV irradiation is dependent on the presence of the transcription factor substrate Atf1. We have used genetic analysis to define the role of c-Jun in activation of the mammalian JNK signaling pathway. Our results show that optimal activation of JNK requires the presence of its transcription factor substrate c-Jun. Mutational analysis shows that the ability of c-Jun to support efficient activation of JNK requires the ability of Jun to bind DNA, suggesting a transcriptional mechanism. Consistent with this, we show that c-Jun represses the expression of several MAP kinase phosphatases. In the absence of c-Jun, the increased expression of MAP kinase phosphatases leads to impaired activation of the ERK, JNK, and p38 MAP kinases after pathway activation. The results show that one function of c-Jun is to regulate the efficiency of signaling by the ERK, p38, and JNK MAP kinases, a function that is likely to affect cellular responses to many different stimuli

Gene activated by growth factors is related to the oncogene v-jun

International Nuclear Information System (INIS)

Ryder, K.; Lau, L.F.; Nathans, D.

1988-01-01

The authors have recently identified by cDNA cloning a set of genes that are rapidly activated in cultured mouse cells by protein growth factors. Here they report that the nucleotide sequence of a cDNA (clone 465) derived from one of these immediate early genes (hereafter called jun-B) encodes a protein homologous to that encoded by the avian sarcoma virus 17 oncogene v-jun. Homology between the jun-B and v-jun proteins is in two regions: one near the N terminus and the other at the C terminus. The latter sequence was shown to have regions of sequence similarity to the DNA-binding domain of the yeast transcriptional regulatory protein GCN4 and to the oncogenic protein fos. Southern blots of human, mouse, and chicken DNA demonstrate that jun-B and c-jun are different genes and that there may be other vertebrate genes related to jun-B and c-jun. These findings suggest that there is a jun family of genes encoding related transcriptional regulatory proteins. The jun-B protein, and perhaps other members of the jun family, may play a role in regulating the genomic response to growth factors

Diazido{(S-1-phenyl-N,N-bis[(2-pyridylmethyl]ethanamine}copper(II

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Sankara Rao Rowthu

2011-07-01

Full Text Available In the title compound, [Cu(N32(C20H21N3], the CuII ion is coordinated by the three N atoms of the (S-1-phenyl-N,N-bis[(2-pyridylmethyl]ethanamine ligand and two N atoms from two azide anions, resulting in a distorted square-pyramidal environment. A weak intermolecular C—H...N hydrogen-bonding interaction between one pyridine group of the ligand and an azide N atom of an adjacent complex unit gives a one-dimensional chain structure parallel to the c axis.

Roles of N- and C-terminal domains in the ligand-binding properties of cytoglobin.

Science.gov (United States)

Hanai, Shumpei; Tsujino, Hirofumi; Yamashita, Taku; Torii, Ryo; Sawai, Hitomi; Shiro, Yoshitsugu; Oohora, Koji; Hayashi, Takashi; Uno, Tadayuki

2018-02-01

Cytoglobin (Cygb) is a member of the hexacoordinated globin protein family and is expressed ubiquitously in rat and human tissues. Although Cygb is reportedly upregulated under hypoxic conditions both in vivo and in vitro, suggesting a physiological function to protect cells under hypoxic/ischemic conditions by scavenging reactive oxygen species or by signal transduction, the mechanisms associated with this function have not been fully elucidated. Recent studies comparing Cygbs among several species suggest that mammalian Cygbs show a distinctly longer C-terminal domain potentially involved in unique physiological functions. In this study, we prepared human Cygb mutants (ΔC, ΔN, and ΔNC) with either one or both terminal domains truncated and investigated the enzymatic functions and structural features by spectroscopic methods. Evaluation of the superoxide-scavenging activity between Cygb variants showed that the ΔC and ΔNC mutants exhibited slightly higher activity involving superoxide scavenging as compared with wild-type Cygb. Subsequent experiments involving ligand titration, flash photolysis, and resonance Raman spectroscopic studies suggested that the truncation of the C- and N-terminal domains resulted in less effective to dissociation constants and binding rates for carbon monoxide, respectively. Furthermore, structural stability was assessed by guanidine hydrochloride and revealed that the C-terminal domain might play a vital role in improving structure, whereas the N-terminal domain did not exert a similar effect. These findings indicated that long terminal domains could be important not only in regulating enzymatic activity but also for structural stability, and that the domains might be relevant to other hypothesized physiological functions for Cygb. Copyright © 2017 Elsevier Inc. All rights reserved.

Crystal structure of bis[2,5-bis(pyridin-2-yl-1,3,4-thiadiazole-κ2N2,N3]bis(thiocyanato-κScopper(II

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Abdelhakim Laachir

2016-08-01

Full Text Available The mononuclear title complex, [Cu(SCN2(C12H8N4S2], was obtained by the reaction of 2,5-bis(pyridin-2-yl-1,3,4-thiadiazole and potassium thiocyanate with copper(II chloride dihydrate. The copper cation lies on an inversion centre and displays an elongated octahedral coordination geometry. The equatorial positions are occupied by the N atoms of two 2,5-bis(pyridin-2-yl-1,3,4-thiadiazole ligands, whereas the axial positions are occupied by the S atoms of two thiocyanate anions. The thiadiazole and the pyridyl rings linked to the metal are approximately coplanar, with a maximum deviation from the mean plane of 0.190 (2 Å. The cohesion of the crystal structure is ensured by weak C—H...N hydrogen bonds and π–π interactions between parallel pyridyl rings of neighbouring molecules [centroid-to-centroid distance = 3.663 (2 Å], leading to a three-dimensional network.

Bis[2-(1,3-benzothiazol-2-ylphenyl-κ2C1,N][1,3-bis(4-bromophenylpropane-1,3-dionato-κ2O,O′]iridium(III

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Sung Kwon Kang

2013-08-01

Full Text Available The title complex, [Ir(C15H9Br2O2(C13H8NS2], lies about a crystallographic twofold rotation axis passing through the IrIII atom and the central C atom of the bis(bromophenylpropane-1,3-dionate ligand. The IrIII atom adopts a distorted octahedral geometry coordinated by two N atoms in the axial positions, and two C and two O atoms in the equatorial plane. The dihedral angle between the two thiazole ring systems in the complex is 77.45 (10°.

Functional interaction between the N- and C-terminal domains of murine leukemia virus surface envelope protein

International Nuclear Information System (INIS)

Lu, C.-W.; Roth, Monica J.

2003-01-01

A series of murine leukemia viruses (MuLVs) with chimeric envelope proteins (Env) was generated to map functional interactions between the N- and the C-terminal domains of surface proteins (SU). All these chimeras have the 4070A amphotropic receptor-binding region flanked by various lengths of Moloney ecotropic N- and C-terminal Env. A charged residue, E49 (E16 on the mature protein), was identified at the N-terminals of Moloney MuLV SU that is important for the interaction with the C-terminal domain of the SU. The region that interacts with E49 was localized between junction 4 (R265 of M-MuLV Env) and junction 6 (L374 of M-MuLV Env) of SU. Sequencing the viable chimeric Env virus populations identified residues within the SU protein that improved the replication kinetics of the input chimeric Env viruses. Mutations in the C-domain of SU (G387E/R, L435I, L442P) were found to improve chimera IV4, which displayed a delayed onset of replication. The replication of AE6, containing a chimeric junction in the SU C-terminus, was improved by mutations in the N-domain (N40H, E80K), the proline-rich region (Q252R), or the transmembrane protein (L538N). Altogether, these observations provide insights into the structural elements required for Env function

The adeno-associated virus major regulatory protein Rep78-c-Jun-DNA motif complex modulates AP-1 activity

International Nuclear Information System (INIS)

Prasad, C. Krishna; Meyers, Craig; Zhan Dejin; You Hong; Chiriva-Internati, Maurizio; Mehta, Jawahar L.; Liu Yong; Hermonat, Paul L.

2003-01-01

Multiple epidemiologic studies show that adeno-associated virus (AAV) is negatively associated with cervical cancer (CX CA), a cancer which is positively associated with human papillomavirus (HPV) infection. Mechanisms for this correlation may be by Rep78's (AAV's major regulatory protein) ability to bind the HPV-16 p97 promoter DNA and inhibit transcription, to bind and interfere with the functions of the E7 oncoprotein of HPV-16, and to bind a variety of HPV-important cellular transcription factors such as Sp1 and TBP. c-Jun is another important cellular factor intimately linked to the HPV life cycle, as well as keratinocyte differentiation and skin development. Skin is the natural host tissue for both HPV and AAV. In this article it is demonstrated that Rep78 directly interacts with c-Jun, both in vitro and in vivo, as analyzed by Western blot, yeast two-hybrid cDNA, and electrophoretic mobility shift-supershift assay (EMSA supershift). Addition of anti-Rep78 antibodies inhibited the EMSA supershift. Investigating the biological implications of this interaction, Rep78 inhibited the c-Jun-dependent c-jun promoter in transient and stable chloramphenicol acetyl-transferase (CAT) assays. Rep78 also inhibited c-Jun-augmented c-jun promoter as well as the HPV-16 p97 promoter activity (also c-Jun regulated) in in vitro transcription assays in T47D nuclear extracts. Finally, the Rep78-c-Jun interaction mapped to the amino-half of Rep78. The ability of Rep78 to interact with c-Jun and down-regulate AP-1-dependent transcription suggests one more mechanism by which AAV may modulate the HPV life cycle and the carcinogenesis process

(μ-Acetato-κ2O:O′[μ-2,6-bis({bis[(pyridin-2-yl-κNmethyl]amino-κN}methyl-4-methylphenolato-κ2O:O](methanol-κOdizinc bis(perchlorate

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Biswanath Das

2014-04-01

Full Text Available The binuclear title complex, [Zn2(C33H33N6O(CH3COO2(CH3OH](ClO42, was synthesized by the reaction between 2,6-bis({[bis(pyridin-2-ylmethyl]amino}methyl-4-methylphenol (H-BPMP, Zn(OAc2 and NaClO4. The two ZnII ions are bridged by the phenolate O atom of the octadentate ligand and the acetate group. An additional methanol ligand is terminally coordinated to one of the ZnII ions, rendering the whole structure unsymmetric. Other symmetric dizinc complexes of BPMP have been reported. However, to the best of our knowledge, the present structure, in which the two ZnII ions are distinguishable by the number of coordinating ligands and the coordination geometries (octahedral and square-pyramidal, is unique. The dizinc complex is a dication, and two perchlorate anions balance the charge. The –OH group of the coordinating methanol solvent molecule forms a hydrogen bond with a perchlorate counter-anion. One of the anions is disordered over two sets of sites with an occupancy ratio of 0.734 (2:0.266 (2.

Expression of c-fos and c-jun proteins in the marginal division of the rat striatum during learning and memory training

Institute of Scientific and Technical Information of China (English)

BAO Xin-min; SHU Si-yun; WANG Hong

2005-01-01

Background A new brain region, the marginal division (MrD), was discovered at the caudal margin of the neostriatum. The MrD was shown to be involved in learning and memory in the rat. The aim of this study was to investigate the expression of the immediate-early genes c-fos and c-jun in the MrD of the striatum during learning and memory processes in the rat, immunocytochemical and Western blot methods were used to examine Y-maze trained rats.Methods The rats were divided into three groups, namely the training, pseudotraining, and control groups. After Y-maze training, the expression of the immediate-early genes c-fos and c-jun in the MrD of the rats was investigated using immunocytochemical and Western blot methods. Results After one hour of Y-maze training, the expression of c-jun and c-fos proteins was significantly enhanced in the MrD; the c-jun protein, in particular, was more intensely expressed in this region than in other parts of the striatum. The expression of these two proteins in the training group was significantly higher than in the pseudotraining and control groups. In addition, positive expression was also found in the hippocampus, cingulum cortex, thalamus, and in other areas. Western blot disclosed two immunoreactive bands for the anti-c-fos antibody (47 kD and 54 kD) and two immunoreactive bands for the anti-c-jun antibody (39 kD and 54 kD). Conclusions These results indicate that the immediate-early genes c-fos and c-jun participate in signal transduction during the learning and memory processes associated with Y-maze training in rats.

Synthesis of 1,1-Diborylalkenes through a Bronsted Base Catalyzed Reaction between Terminal Alkynes and Bis(pinacolato)diboron

OpenAIRE

Morinaga, Akira; Nagao, Kazunori; Ohmiya, Hirohisa; Sawamura, Masaya

2015-01-01

A method for the synthesis of 1,1-diborylalkenes through a Bronsted base catalyzed reaction between terminal alkynes and bis(pinacolato)diboron has been developed. The procedure allows direct synthesis of functionalized 1,1-diborylalkenes from various terminal alkynes including propiolates, propiolamides, and 2-ethynylazoles.

Exercise training protects against atherosclerotic risk factors through vascular NADPH oxidase, extracellular signal-regulated kinase 1/2 and stress-activated protein kinase/c-Jun N-terminal kinase downregulation in obese rats.

Science.gov (United States)

Touati, Sabeur; Montezano, Augusto C I; Meziri, Fayçal; Riva, Catherine; Touyz, Rhian M; Laurant, Pascal

2015-02-01

Exercise training reverses atherosclerotic risk factors associated with metabolic syndrome and obesity. The aim of the present study was to determine the molecular anti-inflammatory, anti-oxidative and anti-atherogenic effects in aorta from rats with high-fat diet-induced obesity. Male Sprague-Dawley rats were placed on a high-fat (HFD) or control (CD) diet for 12 weeks. The HFD rats were then divided into four groups: (i) sedentary HFD-fed rats (HFD-S); (ii) exercise trained (motor treadmill 5 days/week, 60 min/day, 12 weeks) HFD-fed rats (HFD-Ex); (iii) modified diet (HFD to CD) sedentary rats (HF/CD-S); and (iv) an exercise-trained modified diet group (HF/CD-Ex). Tissue levels of NADPH oxidase (activity and expression), NADPH oxidase (Nox) 1, Nox2, Nox4, p47(phox) , superoxide dismutase (SOD)-1, angiotensin AT1 and AT2 receptors, phosphorylated mitogen-activated protein kinase (MAPK; extracellular signal-regulated kinase (ERK) 1/2, stress-activated protein kinase (SAPK)/c-Jun N-terminal kinase (JNK)) and vascular cell adhesion molecule-1 (VCAM-1) were determined in the aorta. Plasma cytokines (tumour necrosis factor (TNF)-α and interleukin (IL)-6) levels were also measured. Obesity was accompanied by increases in NADPH oxidase activity, p47(phox) translocation, Nox4 and VCAM-1 protein expression, MAPK (ERK1/2, SAPK/JNK) phosphorylation and plasma TNF-α and IL-6 levels. Exercise training and switching from the HFD to CD reversed almost all these molecular changes. In addition, training increased aortic SOD-1 protein expression and decreased ERK1/2 phosphorylation. These findings suggest that protective effects of exercise training on atherosclerotic risk factors induced by obesity are associated with downregulation of NADPH oxidase, ERK1/2 and SAPK/JNK activity and increased SOD-1 expression. © 2014 Wiley Publishing Asia Pty Ltd.

C/EBPβ LIP and c-Jun synergize to regulate expression of the murine progesterone receptor.

Science.gov (United States)

Wang, Weizhong; Do, Han Ngoc; Aupperlee, Mark D; Durairaj, Srinivasan; Flynn, Emily E; Miksicek, Richard J; Haslam, Sandra Z; Schwartz, Richard C

2018-06-02

CCAAT/enhancer binding protein β (C/EBPβ) is required for murine mammary ductal morphogenesis and alveologenesis. Progesterone is critical for proliferation and alveologenesis in adult mammary glands, and there is a similar requirement for progesterone receptor isoform B (PRB) in alveologenesis. We examined C/EBPβ regulation of PR expression. All three C/EBPβ isoforms, including typically inhibitory LIP, transactivated the PR promoter. LIP, particularly, strongly synergized with c-Jun to drive PR transcription. Endogenous C/EBPβ and c-Jun stimulated a PR promoter-reporter and these two factors showed promoter occupancy on the endogenous PR gene. Additionally, LIP overexpression elevated endogenous PR protein expression. In pregnancy, both PRB and the relative abundance of LIP among C/EBPβ isoforms increase. Consistent with a role in PRB expression, in vivo C/EBPβ and PR isoform A expression showed mutually exclusive localization in mammary epithelium, while C/EBPβ and PRB largely co-localized. We suggest a critical role for C/EBPβ, particularly LIP, in PRB expression. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Crystal structures of bis[2-(pyridin-2-ylphenyl-κ2N,C1]rhodium(III complexes containing an acetonitrile or monodentate thyminate(1− ligand

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Mika Sakate

2016-04-01

Full Text Available The crystal structures of bis[2-(pyridin-2-ylphenyl]rhodium(III complexes with the metal in an octahedral coordination containing chloride and acetonitrile ligands, namely (OC-6-42-acetonitrilechloridobis[2-(pyridin-2-ylphenyl-κ2N,C1]rhodium(III, [RhCl(C11H8N2(CH3CN] (1, thyminate(1− and methanol, namely (OC-6-42-methanol(5-methyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1-ido-κN1bis[2-(pyridin-2-ylphenyl-κ2N,C1]rhodium(III, [Rh(C11H8N2(C5H5N2O2(CH3OH]·CH3OH·0.5H2O (2, and thyminate(1− and ethanol, namely (OC-6-42-ethanol(5-methyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1-ido-κN1bis[2-(pyridin-2-ylphenyl-κ2N,C1]rhodium(III, [Rh(C11H8N2(C5H5N2O2(C2H5OH]·C2H5OH (3, are reported. The acetonitrile complex, 1, is isostructural with the IrIII analog. In complexes 2 and 3, the monodeprotonated thyminate (Hthym− ligand coordinates to the RhIII atom through the N atom, and the resulting Rh—N(Hthym bond lengths are relatively long [2.261 (2 and 2.252 (2 Å for 2 and 3, respectively] as compared to the Rh—N bonds in the related thyminate complexes. In each of the crystals of 2 and 3, the complexes are linked via a pair of intermolecular N—H...O hydrogen bonds between neighbouring Hthym− ligands, forming an inversion dimer. A strong intramolecular O—H...O hydrogen bond between the thyminate(1− and alcohol ligands in mutually cis positions to each other is also observed.

The AP-1 Transcription Factor c-Jun Promotes Arthritis by Regulating Cyclooxygenase-2 and Arginase-1 Expression in Macrophages.

Science.gov (United States)

Hannemann, Nicole; Jordan, Jutta; Paul, Sushmita; Reid, Stephen; Baenkler, Hanns-Wolf; Sonnewald, Sophia; Bäuerle, Tobias; Vera, Julio; Schett, Georg; Bozec, Aline

2017-05-01

Activation of proinflammatory macrophages is associated with the inflammatory state of rheumatoid arthritis. Their polarization and activation are controlled by transcription factors such as NF-κB and the AP-1 transcription factor member c-Fos. Surprisingly, little is known about the role of the AP-1 transcription factor c-Jun in macrophage activation. In this study, we show that mRNA and protein levels of c-Jun are increased in macrophages following pro- or anti-inflammatory stimulations. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment cluster analyses of microarray data using wild-type and c-Jun-deleted macrophages highlight the central function of c-Jun in macrophages, in particular for immune responses, IL production, and hypoxia pathways. Mice deficient for c-Jun in macrophages show an amelioration of inflammation and bone destruction in the serum-induced arthritis model. In vivo and in vitro gene profiling, together with chromatin immunoprecipitation analysis of macrophages, revealed direct activation of the proinflammatory factor cyclooxygenase-2 and indirect inhibition of the anti-inflammatory factor arginase-1 by c-Jun. Thus, c-Jun regulates the activation state of macrophages and promotes arthritis via differentially regulating cyclooxygenase-2 and arginase-1 levels. Copyright © 2017 by The American Association of Immunologists, Inc.

Linear ketenimines. Variable structures of C,C-dicyanoketenimines and C,C-bis-sulfonylketenimines.

Science.gov (United States)

Finnerty, Justin; Mitschke, Ullrich; Wentrup, Curt

2002-02-22

C,C-dicyanoketenimines 10a-c were generated by flash vacuum thermolysis of ketene N,S-acetals 9a-c or by thermal or photochemical decomposition of alpha-azido-beta-cyanocinnamonitrile 11. In the latter reaction, 3,3-dicyano-2-phenyl-1-azirine 12 is also formed. IR spectroscopy of the keteniminines isolated in Ar matrixes or as neat films, NMR spectroscopy of 10c, and theoretical calculations (B3LYP/6-31G) demonstrate that these ketenimines have variable geometry, being essentially linear along the CCN-R framework in polar media (neat films and solution), but in the gas phase or Ar matrix they are bent, as is usual for ketenimines. Experiments and calculations agree that a single CN substituent as in 13 is not enough to enforce linearity, and sulfonyl groups are less effective that cyano groups in causing linearity. C,C-bis(methylsulfonyl)ketenimines 4-5 and a C-cyano-C-(methylsulfonyl)ketenimine 15 are not linear. The compound p-O2NC6H4N=C=C(COOMe)2 previously reported in the literature is probably somewhat linearized along the CCNR moiety. A computational survey (B3LYP/6-31G) of the inversion barrier at nitrogen indicates that electronegative C-substituents dramatically lower the barrier; this is also true of N-acyl substituents. Increasing polarity causes lower barriers. Although N-alkylbis(methylsulfonyl)ketenimines are not calculated to be linear, the barriers are so low that crystal lattice forces can induce planarity in N-methylbis(methylsulfonyl)ketenimine 3.

Aggregation behavior of gemini pyrrolidine-based ionic liquids 1,1'-(butane-1,4-diyl)bis(1-alkylpyrrolidinium) bromide ([C(n)py-4-C(n)py][Br2]) in aqueous solution.

Science.gov (United States)

Zhang, Shaohua; Yan, Han; Zhao, Mingwei; Zheng, Liqiang

2012-04-15

Three gemini pyrrolidine-based ionic liquids, 1,1'-(butane-1,4-diyl)bis(1-alkylpyrrolidinium) bromide ([C(n)py-4-C(n)py][Br(2)], n=10, 12, 14), were synthesized. Their aggregation behavior in aqueous solution was systematically investigated by surface tension, electrical conductivity, and steady-state fluorescence. Compared with their corresponding monomers, N-alkyl-N-methylpyrrolidinium bromide (C(n)MPB), [C(n)py-4-C(n)py][Br(2)], have higher surface activity. The special structure of [C(n)py-4-C(n)py][Br(2)] that has a spacer in their hydrophilic head groups results in a lower surface excess concentration (Γ(max)) and a larger molecular cross-sectional area (A(min)). Electrical conductivity studies show a lower degree of counter-ion binding to the aggregates. A smaller aggregation number (N(agg)) is observed by the pyrene fluorescence quenching method. A series of thermodynamic parameters (ΔG(agg)(0),ΔH(agg)(0),-TΔS(agg)(0)) of aggregation derived from electrical conductivity indicate that the aggregation of [C(n)py-4-C(n)py][Br(2)] is enthalpy-driven, while aggregation of C(n)MPB is entropy-driven at low temperatures but enthalpy-driven at high temperatures. Copyright © 2012 Elsevier Inc. All rights reserved.

[Curcumin alleviates early brain injury following subarachnoid hemorrhage in rats by inhibiting JNK/c-Jun signal pathway].

Science.gov (United States)

Li, Xia; Zhu, Ji

2018-03-01

Objective To investigate the inhibitory effect of curcumin on early brain injury following subarachnoid hemorrhage (SAH) by inhibiting JNK/ c-Jun signal pathway. Methods Sixty adult male SD rats were randomly divided into four groups: sham operation group (sham group), SAH group, SAH group treated with 100 mg/(kg.d) curcumin and SAH group treated with 200 mg/(kg.d) curcumin, with 15 rats in each group. Endovascular puncture was used to induce SAH model. Nissl staining was used to test whether neurons were broken. TUNEL staining was used to detect apoptosis. Immunohistochemistry was used to investigate the expression of caspase-3. Western blot analysis was used to detect the expressions of p-JNK, JNK, p-c-Jun, c-Jun, and caspase-3. Results Nissl staining indicated the decrease of Nissl bodies in SAH group, but increase of Nissl bodies in SAH group treated with curcumin. TUNEL staining showed that there were more apoptotic neurons in SAH group compared with sham group, while apoptotic neurons decreased after the treatment with curcumin, more obviously in the group treated with 200 mg/(kg.d) curcumin. The expressions of p-JNK, JNK, p-c-Jun, c-Jun, and caspase-3 were up-regulated in SAH group compared with sham group. However, the expressions of those proteins were down-regulated after the treatment with curcumin, especially by higher-dose curcumin treatment. Conclusion Curcumin might suppress early brain injury after SAH by inhibiting JNK/c-Jun signal pathway and neuron apoptosis.

Interaction of the N-terminal segment of pulmonary surfactant protein SP-C with interfacial phospholipid films

DEFF Research Database (Denmark)

Plasencia, Inés; Keough, Kevin M W; Perez-Gil, Jesus

2005-01-01

Pulmonary surfactant protein SP-C is a 35-residue polypeptide composed of a hydrophobic transmembrane alpha-helix and a polycationic, palmitoylated-cysteine containing N-terminal segment. This segment is likely the only structural motif the protein projects out of the bilayer in which SP-C is ins......Pulmonary surfactant protein SP-C is a 35-residue polypeptide composed of a hydrophobic transmembrane alpha-helix and a polycationic, palmitoylated-cysteine containing N-terminal segment. This segment is likely the only structural motif the protein projects out of the bilayer in which SP...... or anionic phospholipid monolayers. The peptide expands the pi-A compression isotherms of interfacial phospholipid/peptide films, and perturbs the lipid packing of phospholipid films during compression-driven liquid-expanded to liquid-condensed lateral transitions, as observed by epifluorescence microscopy....... These results demonstrate that the sequence of the SP-C N-terminal region has intrinsic ability to interact with, insert into, and perturb the structure of zwitterionic and anionic phospholipid films, even in the absence of the palmitic chains attached to this segment in the native protein. This effect has been...

Protective Role of Complement C3 Against Cytokine-Mediated beta-Cell Apoptosis

DEFF Research Database (Denmark)

Dos Santos, Reinaldo S.; Marroqui, Laura; Grieco, Fabio A.

2017-01-01

silencing exacerbates apoptosis under both basal condition and following exposure to cytokines, and it increases chemokine expression upon cytokine treatment. C3 exerts its prosurvival effects via AKT activation and c-Jun N-terminal kinase inhibition. Exogenously added C3 also protects against cytokine...

Regulation of hemeoxygenase-1 gene expression by Nrf2 and c-Jun in tertiary butylhydroquinone-stimulated rat primary astrocytes

International Nuclear Information System (INIS)

Park, Jin-Sun; Kim, Hee-Sun

2014-01-01

Highlights: • tBHQ increased HO-1 mRNA and protein levels in rat primary astrocytes. • tBHQ enhanced HO-1 gene transcription in an ARE-dependent manner. • tBHQ increased the nuclear translocation and DNA binding of Nrf2 and c-Jun to ARE. • Nrf2 and c-Jun are involved in the differential modulation of HO-1 expression. • Nrf2 and c-Jun regulate HO-1 expression via their coordinated interaction. - Abstract: Hemeoxygenase-1 (HO-1) is a phase II antioxidant enzyme that is primarily involved in detoxification and cytoprotection in a variety of tissues. However, the mechanism underlying HO-1 gene expression remains unclear. In the present study, we investigated the regulation of HO-1 expression in primary cultured astrocytes by using the natural antioxidant compound tertiary butylhydroquinone (tBHQ). We found that tBHQ increased HO-1 mRNA and protein levels. Promoter analysis revealed that tBHQ enhanced HO-1 gene transcription in an antioxidant response element (ARE)-dependent manner. In addition, tBHQ increased the nuclear translocation and DNA binding of Nrf2 and c-Jun to ARE. Small interfering RNA (siRNA) experiments demonstrated that Nrf2 and c-Jun are involved in the differential modulation of HO-1 expression. Thus, Nrf2 knockdown reduced the basal level of HO-1 expression but did not affect the fold induction by tBHQ. On the other hand, knockdown of c-Jun diminished tBHQ-mediated induction of HO-1 without affecting basal expression. The data suggest that Nrf2 generally modulates the basal expression of HO-1, while c-Jun mediates HO-1 induction in response to tBHQ. The results of co-immunoprecipitation assays demonstrated a physical interaction between Nrf2 and c-Jun in tBHQ-treated astrocytes. The results suggest that Nrf2 and c-Jun regulate HO-1 expression via their coordinated interaction in tBHQ-treated rat primary astrocytes

Development of [103Pd]-labeled-bis(N4-methylthiosemicarbazone) complexes as possible therapeutic agents

International Nuclear Information System (INIS)

Jalilian, A.R.; Sadeghi, M.; Kamrani, Y.Y.

2006-01-01

Due to interesting tumor seeking properties of bis-thiosemicarbazones, two radio palladium-bis-thiosemicarbazone complexes, i.e., [ 103 Pd]-pyruvaldehyde-bis(N 4 -methylthiosemicarbazone) ([ 103 Pd] PTSM) and [ 103 Pd]-diacetyl-bis(N 4 -methylthiosemicarbazone) ([ 103 Pd]ATSM) were prepared according to the analogy of radio copper homologs. Palladium-103 (t 1/2 = 16.96 d) was produced via the 103 Rh(p, n) 103 Pd nuclear reaction with proton energy 18 MeV. The final activity was eluted in form of Pd(NH 3 ) 2 Cl 2 in order to react with bis-thiosemicarbazones to yield [ 103 Pd]-labeled compounds. Chemical purity of the product was confirmed to be below the accepted limits by polarography. [ 103 Pd]-labeled bis-thiosemicarbazones were prepared with a radiochemical yield of more than 80% at room temperature after 60-90 min by vortexing a mixture of thiosemicarbazones and Pd activity in ethanol. The purification of the labeled compounds performed by reverse phase column chromatography using C 18 plus Sep-Pak. Radiochemical purity of more than 99% specific activity of about 12500-13 000 Ci/mol was obtained. The stability of the complexes was checked in final product and presence of human serum at 37 C up to 48 h. The partition co-efficients of the final complexes were determined. The initial physico-chemical properties of the labeled compounds were compared to those of their copper homologues. (orig.)

The EspF N-Terminal of Enterohemorrhagic Escherichia coli O157:H7 EDL933w Imparts Stronger Toxicity Effects on HT-29 Cells than the C-Terminal.

Science.gov (United States)

Wang, Xiangyu; Du, Yanli; Hua, Ying; Fu, Muqing; Niu, Cong; Zhang, Bao; Zhao, Wei; Zhang, Qiwei; Wan, Chengsong

2017-01-01

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 EspF is an important multifunctional protein that destroys the tight junctions of intestinal epithelial cells and promotes host cell apoptosis. However, its molecular mechanism remains elusive. We knocked out the espF sequence (747 bp, Δ espF ), N-terminal sequence (219 bp, Δ espF N ), and C-terminal sequence (528 bp, Δ espF C ) separately using the pKD46-mediated λ Red homologous recombination system. Then, we built the corresponding complementation strains, namely, Δ espF/pespF , Δ espF N /pespF N , and Δ espF C /pespF C by overlap PCR, which were used in infecting HT-29 cells and BALB/C mice. The level of reactive oxygen species, cell apoptosis, mitochondrial trans-membrane potential, inflammatory factors, transepithelial electrical resistance (TER), and animal mortality were evaluated by DCFH-DA, double staining of Annexin V-FITC/PI, JC-1 staining, ELISA kit, and a mouse assay. The wild-type (WT), Δ espF , Δ espF/pespF , Δ espF C , Δ espF C /pespF C , Δ espF N , and Δ espF N /pespF N groups exhibited apoptotic rates of 68.3, 27.9, 64.9, 65.7, 73.4, 41.3, and 35.3% respectively, and mean TNF-α expression levels of 428 pg/mL, 342, 466, 446, 381, 383, and 374 pg/mL, respectively. In addition, the apoptotic rates and TNF-α levels of the WT, Δ espF/pespF , and Δ espF C were significantly higher than that of Δ espF , Δ espF N , Δ espF C /pespF C , and Δ espF N /pespF N group ( p < 0.05). The N-terminal of EspF resulted in an increase in the number of apoptotic cells, TNF-α secretion, ROS generation, mitochondria apoptosis, and pathogenicity in BalB/c mice. In conclusion, the N-terminal domain of the Enterohemorrhagic E. coli O157:H7 EspF more strongly promotes apoptosis and inflammation than the C-terminal domain.

Protective effect of the poly(ADP-ribose polymerase inhibitor PJ34 on mitochondrial depolarization-mediated cell death in hepatocellular carcinoma cells involves attenuation of c-Jun N-terminal kinase-2 and protein kinase B/Akt activation

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Radnai Balazs

2012-05-01

Full Text Available Abstract Background 2,4-Dimethoxyphenyl-E-4-arylidene-3-isochromanone (IK11 was previously described to induce apoptotic death of A431 tumor cells. In this report, we investigated the molecular action of IK11 in the HepG2 human hepatocellular carcinoma cell line to increase our knowledge of the role of poly (ADP-ribose-polymerase (PARP, protein kinase B/Akt and mitogen activated protein kinase (MAPK activation in the survival and death of tumor cells and to highlight the possible role of PARP-inhibitors in co-treatments with different cytotoxic agents in cancer therapy. Results We found that sublethal concentrations of IK11 prevented proliferation, migration and entry of the cells into their G2 phase. At higher concentrations, IK11 induced reactive oxygen species (ROS production, mitochondrial membrane depolarization, activation of c-Jun N-terminal kinase 2 (JNK2, and substantial loss of HepG2 cells. ROS production appeared marginal in mediating the cytotoxicity of IK11 since N-acetyl cysteine was unable to prevent it. However, the PARP inhibitor PJ34, although not a ROS scavenger, strongly inhibited both IK11-induced ROS production and cell death. JNK2 activation seemed to be a major mediator of the effect of IK11 since inhibition of JNK resulted in a substantial cytoprotection while inhibitors of the other kinases failed to do so. Inhibition of Akt slightly diminished the effect of IK11, while the JNK and Akt inhibitor and ROS scavenger trans-resveratrol completely protected against it. Conclusions These results indicate significant involvement of PARP, a marginal role of ROS and a pro-apoptotic role of Akt in this system, and raise attention to a novel mechanism that should be considered when cancer therapy is augmented with PARP-inhibition, namely the cytoprotection by inhibition of JNK2.

Solution structure of the N-terminal domain of a replication restart primosome factor, PriC, in Escherichia coli

Science.gov (United States)

Aramaki, Takahiko; Abe, Yoshito; Katayama, Tsutomu; Ueda, Tadashi

2013-01-01

In eubacterial organisms, the oriC-independent primosome plays an essential role in replication restart after the dissociation of the replication DNA-protein complex by DNA damage. PriC is a key protein component in the replication restart primosome. Our recent study suggested that PriC is divided into two domains: an N-terminal and a C-terminal domain. In the present study, we determined the solution structure of the N-terminal domain, whose structure and function have remained unknown until now. The revealed structure was composed of three helices and one extended loop. We also observed chemical shift changes in the heteronuclear NMR spectrum and oligomerization in the presence of ssDNA. These abilities may contribute to the PriC-ssDNA complex, which is important for the replication restart primosome. PMID:23868391

Peptide-DNA conjugates as tailored bivalent binders of the oncoprotein c-Jun.

Science.gov (United States)

Pazos, Elena; Portela, Cecilia; Penas, Cristina; Vázquez, M Eugenio; Mascareñas, José L

2015-05-21

We describe a ds-oligonucleotide-peptide conjugate that is able to efficiently dismount preformed DNA complexes of the bZIP regions of oncoproteins c-Fos and c-Jun (AP-1), and therefore might be useful as disrupters of AP-1-mediated gene expression pathways.

Superficial disposition of the N-terminal region of the surfactant protein SP-C and the absence of specific SP-B-SP-C interactions in phospholipid bilayers

DEFF Research Database (Denmark)

Plasencia, I; Cruz, A; Casals, C

2001-01-01

. The fluorescence emission spectrum of Dns-SP-C in phospholipid bilayers is similar to the spectrum of dansyl-phosphatidylethanolamine, and indicates that the N-terminal end of the protein is located at the surface of the membranes and is exposed to the aqueous environment. In membranes containing...... phosphatidylglycerol (PG), the fluorescence of Dns-SP-C shows a 3-fold increase with respect to the fluorescence of phosphatidylcholine (PC), suggesting that electrostatic lipid-protein interactions induce important effects on the structure and disposition of the N-terminal segment of the protein in these membranes...... of the N-terminal segment of the protein into less polar environments that originate during protein lateral segregation. This suggests that conformation and interactions of the N-terminal segment of SP-C could be important in regulating the lateral distribution of the protein in surfactant bilayers...

Crystal structures of three co-crystals of 1,2-bis-(pyridin-4-yl)ethane with 4-alk-oxy-benzoic acids: 4-eth-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1), 4-n-propoxybenzoic acid-1,2-bis(pyridin-4-yl)ethane (2/1) and 4-n-but-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1).

Science.gov (United States)

Tabuchi, Yohei; Gotoh, Kazuma; Ishida, Hiroyuki

2015-11-01

The crystal structures of three hydrogen-bonded co-crystals of 4-alk-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1), namely, 2C9H10O3·C12H12N2, (I), 2C10H12O3·C12H12N2, (II), and 2C11H14O3·C12H12N2, (III), have been determined at 93, 290 and 93 K, respectively. In (I), the asymmetric unit consists of one 4-eth-oxy-benzoic acid mol-ecule and one half-mol-ecule of 1,2-bis-(pyridin-4-yl)ethane, which lies on an inversion centre. In (II) and (III), the asymmetric units each comprise two crystallographically independent 4-alk-oxy-benzoic acid mol-ecules and one 1,2-bis-(pyridin-4-yl)ethane mol-ecule. In each crystal, the two components are linked by O-H⋯N hydrogen bonds, forming a linear hydrogen-bonded 2:1unit of the acid and the base. Similar to the structure of 2:1 unit of (I), the units of (II) and (III) adopt nearly pseudo-inversion symmetry. The 2:1 units of (I), (II) and (III) are linked via C-H⋯O hydrogen bonds, forming tape structures.

μ-Carbonato-bis-(bis-{2-[(diethyl-amino)-meth-yl]phen-yl}bis-muth(III)).

Science.gov (United States)

Soran, Albert P; Nema, Mihai G; Breunig, Hans J; Silvestru, Cristian

2011-01-12

The mol-ecular structure of the title compound, [Bi(2)(C(11)H(16)N)(4)(CO(3))], consists of a symmetrically bridging carbonato group which binds two [2-Et(2)NCH(2)C(6)H(4)](2)Bi units that are crystallographically related via a twofold rotation axis bis-ecting the carbonate group. The two Bi atoms and two of the C atoms directly bonded to bis-muth are quasi-planar [deviations of 0.323 (1) and 0.330 (9)Å for the Bi and C atoms, respectively] with the carbonate group. The remaining two ligands are in a trans arrangement relative to the quasi-planar (CBi)(2)CO(3) system. The metal atom is strongly coordinated by the N atom of one pendant arm [Bi-N = 2.739 (6) Å], almost trans to the O atom, while the N atom of the other pendant arm exhibits a weaker intra-molecular inter-action [Bi⋯N = 3.659 (7) Å] almost trans to a C atom. If both these intra-molecular N→Bi inter-actions per metal atom are considered, the overall coordination geometry at bis-muth becomes distorted square-pyramidal [(C,N)(2)BiO cores] and the compound can be described as a hypervalent 12-Bi-5 species. Additional quite short intra-molecular Bi⋯O inter-actions are also present [3.796 (8)-4.020 (9) Å]. Inter-molecular associations through weak η(6)⋯Bi inter-actions [Bi⋯centroid of benzene ring = 3.659 (1) Å] lead to a ribbon-like supra-molecular association.

A novel enantiopure proline-based organickel(III) halide monocation with a pentadentate C, N2, O2-bonded bis(ortho-chelating) aryldiamine ligand

NARCIS (Netherlands)

Koten, G. van; Kuil, L.A. van de; Veldhuizen, Y.S.J.; Grove, D.M.; Zwikker, J.W.; Jenneskens, L.W.; Drenth, W.; Smeets, W.J.J.

1995-01-01

An attempt was made to use the enantiopure arylnickel(II) complex [Ni(L*-N, C, N)Br], 1, (L* is the monoanionic ligand, 2, 6-bis[(2-(S)-2-isopropoxycarbonyl-1-pyrrolidinyl)methyl]phenyl) as a catalyst for the Kharasch addition reaction of CCl4 to alkenes which led instead to a new ionic

Expression of c-Fos and c-Jun in the cornea, lens, and retina after ultraviolet irradiation of the rat eye and effect of topical antisense oligodeoxynucleotides

International Nuclear Information System (INIS)

Gillardon, F.; Zimmermann, M.

1995-01-01

Aims - Immunohistochemical techniques were used to investigate c-Fos and c-Jun proto-oncogene expression in the cornea, lens, and retina after ultraviolet irradiation of the rat eye. Methods -Eyes of anaesthetised rats were exposed to 1.5 J/cm 2 of ultraviolet radiation (280-380 nm). Animals were perfused 1, 6, or 24 hours after irradiation and tissue sections were incubated with specific antiserum to c-Fos and c-Jun, respectively. Non-irradiated contralateral eyes displayed no c-Fos and c-Jun immunoreactivity. One and 6 hours after ultraviolet exposure numerous c-Fos and c-Jun immunopositive nuclei were observed mainly in the epithelial cell layers of the cornea and the lens epithelium. Scattered labelled nuclei were detectable in the retinal ganglion cell layer and the inner nuclear layer. Twenty four hours after irradiation c-Fos and c-Jun protein expression returned to near control levels. Histological signs of ultraviolet damage (for example, chromatin condensation, nuclear fragmentation) were first recognisable in the corneal epithelium 6 hours after irradiation and became more apparent at later times. The rapid and sustained activation of c-Fos and c-Jun expression in the eye after single ultraviolet exposure may represent the molecular mechanism underlying ultraviolet induced photodamage and initiation of cell death. Furthermore, topical application of a c-fos antisense oligode-oxynucleotide to the ultraviolet exposed rat eye inhibited the increase in c-Fos expression in the cornea, suggesting therapeutic activity of antisense drugs in corneal malignant and infectious diseases. (author)

Synthesis, characterization and antioxidant study of N,N’-bis(2-chlorobenzamidothiocarbonyl)hydrazine

Energy Technology Data Exchange (ETDEWEB)

Firdausiah, Syadza; Hasbullah, Siti Aishah; Yamin, Bohari M. [School of Chemical Science and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

2015-09-25

N,N’-bis(2-chlorobenzamidothiocarbonyl)hydrazine was synthesized from 2-chlorobenzoylisothiocyanate and hydrazine in acetone. The compound was characterized by infrared, {sup 1}H and {sup 13}C NMR, and UV-Vis spectroscopies. X-ray crystallography study showed the molecule adopt trans configuration at both N-N and C-N bonds. The compound showed high antioxidant activity, EC{sub 50} of 374.89 µM, compared to ascorbic acid (EC{sub 50} of 561.36 µM)

Bis[N-(3-aminopropylpropane-1,3-diamine-κ3N,N′,N′′]cadmium nitrate perchlorate

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Václav Eigner

2012-03-01

Full Text Available The title complex, [Cd(C6H17N32](ClO4(NO3, was synthesized by the reaction of Cd(NO32·4H2O, bis(3-aminopropylamine and sodium perchlorate in methanol. The asymmetric unit of the title complex consists of one Cd2+ cation, two tridentate bis(3-aminopropylamine ligands, one nitrate anion and one perchlorate anion. The Cd2+ cation is coordinated by six N atoms of the bis(3-aminopropylamine ligands in a slightly distorted octahedral coordination geometry. In the crystal, molecules are held together by an intricate network of N—H...O interactions. One of the two amine ligands was found to be disordered over two sets of sites, with a ratio of 0.802 (3:0.198 (3, similarly to the nitrate anion, with a ratio of 0.762 (10:0.238 (10.

Aplicación de la Agenda 21 en los Planes de Desarrollo Concertado de las provincias del departamento de Junín

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Hugo Miguel Miguel

2015-06-01

Full Text Available Este trabajo de investigación ha tenido como objetivo comprobar la influencia de la Agenda 21 en los planes de desarrollo concertado de los gobiernos locales provinciales del departamento de Junín mediante la inclusión de los indicadores de desarrollo sostenible. Para su ejecución se utilizó el método de investigación descriptivo correlacional. Los instrumentos aplicados fueron fichas de observación de 25 ítems, en función de la estructura lógica de la Agenda 21, dentro de esta: las dimensiones del desarrollo sostenible (económico, social y ambiental. La población de estudio estuvo conformada por los planes de desarrollo concertado de las nueve provincias del departamento de Junín. De la misma forma, la muestra censal estuvo compuesta por los nueve planes de desarrollo concertado provinciales de la región Junín. Algunos de los resultados obtenidos revelan que la influencia de la Agenda 21 en los planes de desarrollo de los gobiernos locales provinciales del departamento de Junín, mediante la inclusión de sus indicadores de desarrollo sostenible (inclusión del 23 % del total de indicadores no fue significativa (p > 0,05, ya que la prueba binomial presenta un valor p de 1, mayor que el nivel usual de significación de 0,05. En conclusión la Agenda 21 que promueve el desarrollo y la cooperación en la esfera del medio ambiente, no influyó significativamente en los planes de desarrollo concertado de los gobiernos locales provinciales del departamento de Junín, porque solo se incluyeron el 23 % de los indicadores de desarrollo sostenible.

Biochemical Characterization of Mycobacterium smegmatis RnhC (MSMEG_4305), a Bifunctional Enzyme Composed of Autonomous N-Terminal Type I RNase H and C-Terminal Acid Phosphatase Domains.

Science.gov (United States)

Jacewicz, Agata; Shuman, Stewart

2015-08-01

Mycobacterium smegmatis encodes several DNA repair polymerases that are adept at incorporating ribonucleotides, which raises questions about how ribonucleotides in DNA are sensed and removed. RNase H enzymes, of which M. smegmatis encodes four, are strong candidates for a surveillance role. Here, we interrogate the biochemical activity and nucleic acid substrate specificity of M. smegmatis RnhC, a bifunctional RNase H and acid phosphatase. We report that (i) the RnhC nuclease is stringently specific for RNA:DNA hybrid duplexes; (ii) RnhC does not selectively recognize and cleave DNA-RNA or RNA-DNA junctions in duplex nucleic acid; (iii) RnhC cannot incise an embedded monoribonucleotide or diribonucleotide in duplex DNA; (iv) RnhC can incise tracts of 4 or more ribonucleotides embedded in duplex DNA, leaving two or more residual ribonucleotides at the cleaved 3'-OH end and at least one or two ribonucleotides on the 5'-PO4 end; (v) the RNase H activity is inherent in an autonomous 140-amino-acid (aa) N-terminal domain of RnhC; and (vi) the C-terminal 211-aa domain of RnhC is an autonomous acid phosphatase. The cleavage specificity of RnhC is clearly distinct from that of Escherichia coli RNase H2, which selectively incises at an RNA-DNA junction. Thus, we classify RnhC as a type I RNase H. The properties of RnhC are consistent with a role in Okazaki fragment RNA primer removal or in surveillance of oligoribonucleotide tracts embedded in DNA but not in excision repair of single misincorporated ribonucleotides. RNase H enzymes help cleanse the genome of ribonucleotides that are present either as ribotracts (e.g., RNA primers) or as single ribonucleotides embedded in duplex DNA. Mycobacterium smegmatis encodes four RNase H proteins, including RnhC, which is characterized in this study. The nucleic acid substrate and cleavage site specificities of RnhC are consistent with a role in initiating the removal of ribotracts but not in single-ribonucleotide surveillance. RnhC

Diaquabis[2,6-bis(4H-1,2,4-triazol-4-ylpyridine-κN2]bis(selenocyanato-κNcobalt(II

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Yuan-Yuan Liu

2012-08-01

Full Text Available In the title compound, [Co(NCSe2(C9H7N72(H2O2], the Co2+ cation is coordinated by two selenocyanate anions, two 2,6-bis(4H-1,2,4-triazol-4-ylpyridine ligands and two water molecules within a slightly distorted N4O2 octahedron. The asymmetric unit consists of one Co2+ cation, which is located on a center of inversion, as well as one selenocyanate anion, one 2,6-bis(4H-1,2,4-triazol-4-ylpyridine ligand and one water molecule in general positions. Intermolecular O—H...N hydrogen bonds join the complex molecules into layers parallel to the bc plane. The layers are linked by C—H...N and C—H...Se hydrogen bonds into a three-dimensional supramolecular architecture.

[μ-N,N′-Bis(2-aminoethylethane-1,2-diamine-κ4N1,N1′:N2,N2′]bis{[N,N′-bis(2-aminoethylethane-1,2-diamine-κ4N,N′,N′′,N′′′]cadmium} tetrakis(perchlorate

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Hamid Goudarziafshar

2012-09-01

Full Text Available The centrosymmetric dinuclear cadmium title complex, [Cd2(C6H18N43](ClO44, was obtained by the reaction of N,N′-bis(2-aminoethylethane-1,2-diamine (trien with Cd(NO32·4H2O and sodium perchlorate in methanol. The CdII cation is coordinated by four N atoms of a non-bridging trien ligand and by two N atoms of a bridging trien ligand in a slightly distorted octahedral coordination geometry. The bridging ligand shares another two N atoms with a neighboring symmetry-equivalent CdII cation. The structure displays C—H...O and N—H...O hydrogen bonding. The perchlorate anion is disordered over two sets of sites in a 0.854 (7: 0.146 (7 ratio.

Expression levels of transcription factors c-Fos and c-Jun and transmembrane protein HAb18G/CD147 in urothelial carcinoma of the bladder.

Science.gov (United States)

Huhe, Muren; Liu, Shuangshuang; Zhang, Yang; Zhang, Zheng; Chen, Zhinan

2017-05-01

The aim of the present study was to investigate the prognostic significance of the expression of transcription factors, c-Fos, c-Jun and transmembrane protein CD147, in urothelial carcinoma of the bladder (UCB). The current study investigated the clinical significance of these factors in the development, progression and survival analysis of UCB. Immunohistochemistry was employed to analyze c‑Fos, c‑Jun and CD147 expression in 41 UCB cases and 34 non‑cancerous human bladder tissues. These results were scored in a semi‑quantitative manner based on the intensity and percentage of tumor cells that presented immunoreactivity. Protein levels of CD147, c‑Fos and c‑Jun expression were upregulated in 22 (53.7%), 10 (24.4%) and 9 (22.0%) UCB cases, respectively. High levels of c‑Jun correlated with the AJCC cancer staging manual (7th edition; P=0.038). Univariate analysis revealed that upregulated CD147 (P=0.038) or c‑Jun (P=0.008) was associated with poor overall survival (OS), respectively. Further analysis revealed that either CD147‑c‑Fos‑c‑Jun co‑expression (P=0.004), or CD147‑c‑Jun co‑expression (P=0.037) and c‑Fos‑c‑Jun co‑expression (PCD147, c‑Jun or c‑Fos were independent risk indicators for death in UCB patients. Increased expression of c‑Jun or CD147, as well as co‑expression of CD147‑c‑Jun, c‑Jun‑c‑Fos or CD147‑c‑Jun‑c‑Fos has prognostic significance for UCB patients. Therefore, high CD147 and c‑Jun expression may serve roles in tumor progression and may be diagnostic and therapeutic targets in UCB whether alone or in combination.

Synthesis of C-glycosyl-bis-1,2,3-triazole derivatives from 3,4,6-tri-O-acetyl-D-glucal.

Science.gov (United States)

Shamim, Anwar; Souza, Frederico B; Trossini, Gustavo H G; Gatti, Fernando M; Stefani, Hélio A

2015-08-01

We have developed an efficient, CuI-catalyzed, microwave-assisted method for the synthesis of bis-1,2,3-triazole derivatives starting from a 3,4,6-tri-O-acetyl-D-glucal-derived mesylate. This mesylate was obtained from 3,4,6-tri-O-acetyl-D-glucal through C-glycosidation, deprotection of acetate groups to alcohols, and selective mesylation of the primary alcohol. This mesylate moiety was then converted to an azide through a microwave-assisted method with good yield. The azide, once synthesized, was then treated with different terminal alkynes in the presence of CuI to synthesize various bis-triazoles in high yields and short reaction times.

MAGE-A1 promotes melanoma proliferation and migration through C-JUN activation

Energy Technology Data Exchange (ETDEWEB)

Wang, Dong [Department of Dermatology, General Hospital of People' s Liberation Army, Beijing 100853 (China); The 309th Hospital of China People' s Liberation Army, Beijing 100091 (China); Wang, Junyun; Ding, Nan [CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Li, Yongjun; Yang, Yaran [CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101 (China); Fang, Xiangdong, E-mail: fangxd@big.ac.cn [CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101 (China); Zhao, Hua, E-mail: luckhua301@163.com [Department of Dermatology, General Hospital of People' s Liberation Army, Beijing 100853 (China)

2016-05-13

MAGE-A1 belongs to the chromosome X-clustered genes of cancer-testis antigen family and is normally expressed in the human germ line but is also overexpressed in various tumors. Previous studies of MAGE-A1 in melanoma mainly focused on methylation changes or its role in immunotherapy, however, its biological functions in melanoma have remained unknown. In order to determine the role of MAGE-A1 in melanoma growth and metastasis, we manipulated melanoma cell lines with overexpression and knockdown of MAGE-A1. Integration of cell proliferation assays, transwell migration and invasion assays, and RNA-Seq analysis revealed that up-regulation of MAGE-A1 dramatically promoted proliferation, migration, and invasion of human melanoma cell lines in vitro, while down-regulation of MAGE-A1 inhibited those characteristics associated with tumor cells. Furthermore, transcriptome sequencing revealed that MAGE-A1 exerts its tumor promoting activity by activating p-C-JUN directly or through ERK-MAPK signaling pathways. Based on our findings, we propose that MAGE-A1 may be a potential therapeutic target for melanoma patients. - Highlights: • MAGE-A1 promotes proliferation and clone formation in melanoma cell lines. • MAGE-A1 enhances tumor cell migration and invasion in melanoma cell lines. • Network including C-JUN, IL8, and ARHGAP29 play critical role in malignant melanoma. • Oncogenic MAGE-A1 increases p-C-JUN levels, possibly via ERK-MAPK signaling pathway.

(μ-Acetato-κ2 O:O′)[μ-2,6-bis­({bis­[(pyri­din-2-yl-κN)meth­yl]amino-κN}meth­yl)-4-methyl­phenolato-κ2 O:O](metha­nol-κO)dizinc bis­(perchlorate)

Science.gov (United States)

Das, Biswanath; Haukka, Matti; Nordlander, Ebbe

2014-01-01

The binuclear title complex, [Zn2(C33H33N6O)(CH3COO2)(CH3OH)](ClO4)2, was synthesized by the reaction between 2,6-bis­({[bis­(pyridin-2-yl)meth­yl]amino}­meth­yl)-4-methyl­phenol (H-BPMP), Zn(OAc)2 and NaClO4. The two ZnII ions are bridged by the phenolate O atom of the octadentate ligand and the acetate group. An additional methanol ligand is terminally coordinated to one of the ZnII ions, rendering the whole structure unsymmetric. Other symmetric dizinc complexes of BPMP have been reported. However, to the best of our knowledge, the present structure, in which the two ZnII ions are distinguishable by the number of coordinating ligands and the coordination geometries (octahedral and square-pyramidal), is unique. The dizinc complex is a dication, and two perchlorate anions balance the charge. The –OH group of the coordinating methanol solvent mol­ecule forms a hydrogen bond with a perchlorate counter-anion. One of the anions is disordered over two sets of sites with an occupancy ratio of 0.734 (2):0.266 (2). PMID:24826088

Dieta de Leopardus colocolo (Carnivora: Felidae en la Reserva Nacional de Junín, Junín, Perú

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Ursula Fajardo

2014-05-01

Full Text Available Este estudio caracteriza la dieta de Leopardus colocolo en los alrededores del lago Junín, en el centro del Perú, a partir de los restos de las presas presentes en 43 heces. El origen de las heces del predador se determinó a partir del ADN mitocondrial de las células epiteliales intestinales adheridas a la superficie de las heces, utilizando como marcador la región de control. Los restos de las presas fueron identificados utilizando literatura especializada y la comparación con especímenes de colección, identificando un total of 14 ítems alimenticios pertenecientes a mamíferos de las familias Cricetidae (6, Chinchillidae (1 y Caviidae (1 y aves de las familias Anatidae (3 y Rallidae (2, y un grupo de aves no identificadas (1. Los roedores fueron el principal componente de la dieta de L. colocolo, en frecuencia y biomasa, seguido por las aves. Entre los ítems alimenticios consumidos, el roedor cricétido pequeño Calomys sp. fue el más frecuente; sin embargo, el mayor aporte de biomasa relativa fue proporcionado por el roedor mediano Cavia tschudii. La amplitud de nicho obtenida fue baja (Bsta= 0.17, indicando una dieta especializada. Nuestros resultados confirman que, como ocurre con la mayoría de felinos pequeños neotropicales, L. colocolo es un predador especializado en la captura de vertebrados, principalmente mamíferos pequeños. No se registró variación estacional en la dieta y el análisis de las clases de edad de los roedores cricétidos mostró que los adultos fueron los más consumidos. Se infiere que L. colocolo tiene un patrón de actividad diurno y nocturno.

Activations of c-fos/c-jun signaling are involved in the modulation of hypothalamic superoxide dismutase (SOD) and neuropeptide Y (NPY) gene expression in amphetamine-mediated appetite suppression

International Nuclear Information System (INIS)

Hsieh, Y.-S.; Yang, S.-F.; Chiou, H.-L.; Kuo, D.-Y.

2006-01-01

Amphetamine (AMPH) is known as an anorectic agent. The mechanism underlying the anorectic action of AMPH has been attributed to its inhibitory action on hypothalamic neuropeptide Y (NPY), an appetite stimulant in the brain. This study was aimed to examine the molecular mechanisms behind the anorectic effect of AMPH. Results showed that AMPH treatment decreased food intake, which was correlated with changes of NPY mRNA level, but increased c-fos, c-jun and superoxide dismutase (SOD) mRNA levels in hypothalamus. To determine if c-fos or c-jun was involved in the anorectic response of AMPH, infusions of antisense oligonucleotide into the brain were performed at 1 h before daily AMPH treatment in freely moving rats, and the results showed that c-fos or c-jun knockdown could block this anorectic response and restore NPY mRNA level. Moreover, c-fos or c-jun knockdown could partially block SOD mRNA level that might involve in the modulation of NPY gene expression. It was suggested that c-fos/c-jun signaling might involve in the central regulation of AMPH-mediated feeding suppression via the modulation of NPY gene expression

Effect of the substituents on the photophysical, electrochemical and electroluminescence properties of OLED dopant Iridium bis(2-phenylbenzothiozolato- N,C2')(acetylacetonate)

Science.gov (United States)

Ivanov, P.; Tomova, R.; Petrova, P.

2014-12-01

The effect of two substituents: clorine and 1,3-diphenylpropane-1,3-dionate, placed on different position in the molecule of Iridium (III) bis(2-phenylbenzothiozolato-N,C2')- (acetylacetonate) (bt)2Ir(acac), on its electrochemical behaviour, photophysical and electroluminescence properties were investigated. Three complexes (bt)2Ir(acac), Iridium (III) bis[2-(4-chlorophenyl)benzothiazolato-N,C2']-acetylacetonate (Clbt)2Ir(acac), in which the Cl atom was introduced on the 4-position in the benzothiazole ring, and the new Iridium (Ill) bis[2 -phenylbenzothiazolato -N,C2'] -(1,3 -diphenylpropane-1,3 -dionate) (bt)2Ir(dbm), where ancillary acetylacetonate ligand was replaced by 1,3-diphenylpropane-1,3-dionate, were synthesized and characterised by 1H-NMR and elemental analysis. The HOMO/LUMO energy levels of the complexes were determined by cyclic voltammetry (CV) and their properties were established by UV-Visible and fluorescence spectroscopy. The application of (Clbt)2Ir(acac), (bt)2Ir(bsm) and (bt)2Ir(acac) as dopants in hole transporting layer (HTL) of Organic light- emitting diodes(OLEDs). It was found that with respect to the reference (bt)2Ir(acac): both LUMO and HOMO of the substituted complexes were shifted to more positive values accordingly with 0.23 and 0.19 eV for (Clbt)2Ir(acac) and 0.14 and 0.12 eV for (bt)2Ir(dbm). OLEDs doped with 1 w% of the complexes irradiated the warm white light with Commission internationale de l'eclairage (CIE) coordinates: 0.24;0.38 for (Clbt)2Ir(acac), 0.30;0.44 for (bt)2Ir(acac) and 0.28;0.46 for (bt)2Ir(dbm). Devices doped with 10 w% of all complexes irradiated in the yellow orange region of the spectrum.

Dual N- and C-terminal helices are required for endoplasmic reticulum and lipid droplet association of alcohol acetyltransferases in Saccharomyces cerevisiae.

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Jyun-Liang Lin

Full Text Available In the yeast Saccharomyces cerevisiae two alcohol acetyltransferases (AATases, Atf1 and Atf2, condense short chain alcohols with acetyl-CoA to produce volatile acetate esters. Such esters are, in large part, responsible for the distinctive flavors and aromas of fermented beverages including beer, wine, and sake. Atf1 and Atf2 localize to the endoplasmic reticulum (ER and Atf1 is known to localize to lipid droplets (LDs. The mechanism and function of these localizations are unknown. Here, we investigate potential mechanisms of Atf1 and Atf2 membrane association. Segments of the N- and C-terminal domains of Atf1 (residues 24-41 and 508-525, respectively are predicted to be amphipathic helices. Truncations of these helices revealed that the terminal domains are essential for ER and LD association. Moreover, mutations of the basic or hydrophobic residues in the N-terminal helix and hydrophobic residues in the C-terminal helix disrupted ER association and subsequent sorting from the ER to LDs. Similar amphipathic helices are found at both ends of Atf2, enabling ER and LD association. As was the case with Atf1, mutations to the N- and C-terminal helices of Atf2 prevented membrane association. Sequence comparison of the AATases from Saccharomyces, non-Saccharomyces yeast (K. lactis and P. anomala and fruits species (C. melo and S. lycopersicum showed that only AATases from Saccharomyces evolved terminal amphipathic helices. Heterologous expression of these orthologs in S. cerevisiae revealed that the absence of terminal amphipathic helices eliminates LD association. Combined, the results of this study suggest a common mechanism of membrane association for AATases via dual N- and C-terminal amphipathic helices.

Transition metal coordination chemistry ofN,N-bis(2-{pyrid-2-ylethyl})hydroxylamine.

Science.gov (United States)

Belock, Christopher W; Cetin, Anil; Barone, Natalie V; Ziegler, Christopher J

2008-08-18

Although directly relevant to metal mediated biological nitrification as well as the coordination chemistry of peroxide, the metal complexes of hydroxylamines and their functionalized variants remain largely unexplored. The chelating hydroxylamine ligand N,N-bis(2-{pyrid-2-ylethyl})hydroxylamine can be readily generated via a solvent free reaction in high purity; however, the ligand is prone to decomposition which can hamper metal reaction. N,N-bis(2-{pyrid-2-ylethyl})hydroxylamine forms stable complexes with chromium(III), manganese(II), nickel(II), and cadmium(II) ions, coordinating in a side-on mode in the case of chromium and via the nitrogen in the case of the latter three metal ions. The hydroxylamine ligand can also be reduced to form N,N-bis(2-{pyrid-2-ylethyl})amine upon exposure to a stoichiometric amount of the metal salts cobalt(II) nitrate, vanadium(III) chloride, and iron(II) chloride. In the reaction with cobalt nitrate, the reduced ligand then chelates to the metal to form [N,N-bis(2-{pyrid-2-ylethyl})amine]dinitrocobalt(II). Upon reaction with vanadium(III) chloride and iron(III) chloride, the reduced ligand is isolated as the protonated free base, resulting from a metal-mediated decomposition reaction.

Zirconium and Titanium Propylene Polymerization Precatalysts Supported by a Fluxional C 2 -Symmetric Bis(anilide)pyridine Ligand

KAUST Repository

Tonks, Ian A.

2012-03-12

Titanium and zirconium complexes supported by a bis(anilide)pyridine ligand (NNN = pyridine-2,6-bis(N-mesitylanilide)) have been synthesized and crystallographically characterized. C 2-symmetric bis(dimethylamide) complexes were generated from aminolysis of M(NMe 2) 4 with the neutral, diprotonated NNN ligand or by salt metathesis of the dipotassium salt of NNN with M(NMe 2) 2Cl 2. In contrast to the case for previously reported pyridine bis(phenoxide) complexes, the ligand geometry of these complexes appears to be dictated by chelate ring strain rather than metal-ligand π bonding. The crystal structures of the five-coordinate dihalide complexes (NNN)MCl 2 (M = Ti, Zr) display a C 1-symmetric geometry with a stabilizing ipso interaction between the metal and the anilido ligand. Coordination of THF to (NNN)ZrCl 2 generates a six-coordinate C 2-symmetric complex. Facile antipode interconversion of the C 2 complexes, possibly via flat C 2v intermediates, has been investigated by variable-temperature 1H NMR spectroscopy for (NNN)MX 2(THF) n (M = Ti, Zr; X = NMe 2, Cl) and (NNN)Zr(CH 2Ph) 2. These complexes were tested as propylene polymerization precatalysts, with most complexes giving low to moderate activities (10 2-10 4 g/(mol h)) for the formation of stereoirregular polypropylene. © 2012 American Chemical Society.

Properties of catalase-peroxidase lacking its C-terminal domain

International Nuclear Information System (INIS)

Baker, Ruletha D.; Cook, Carma O.; Goodwin, Douglas C.

2004-01-01

Catalase-peroxidases have a two-domain structure. The N-terminal domain contains the bifunctional active site, but the function of the C-terminal domain is unknown. We produced catalase-peroxidase containing only its N-terminal domain (KatG Nterm ). Removal of the C-terminal domain did not result in unexpected changes in secondary structure as evaluated by CD, but KatG Nterm had neither catalase nor peroxidase activity. Partial recovery of both activities was achieved by incubating KatG Nterm with the separately expressed and isolated KatG C-terminal domain. Spectroscopic measurements revealed a shift in heme environment from a mixture of high-spin species (wtKatG) to exclusively hexacoordinate, low-spin (KatG Nterm ). Moreover, a >1000-fold lower k on for CN - binding was observed for KatG Nterm . EPR spectra for KatG Nterm and the results of site-specific substitution of active site histidines suggested that the distal histidine was the sixth ligand. Thus, one important role for the C-terminal domain may be to support the architecture of the active site, preventing heme ligation by this catalytically essential residue

A prawn core histone 4: derivation of N- and C-terminal peptides and their antimicrobial properties, molecular characterization and mRNA transcription.

Science.gov (United States)

Chaurasia, Mukesh Kumar; Palanisamy, Rajesh; Bhatt, Prasanth; Kumaresan, Venkatesh; Gnanam, Annie J; Pasupuleti, Mukesh; Kasi, Marimuthu; Harikrishnan, Ramaswamy; Arockiaraj, Jesu

2015-01-01

This study investigates the complete molecular characterization including bioinformatics characterization, gene expression, synthesis of N and C terminal peptides and their antimicrobial activity of the core histone 4 (H4) from freshwater giant prawn Macrobrachium rosenbergii (Mr). A cDNA encoding MrH4 was identified from the constructed cDNA library of M. rosenbergii during screening and the sequence was obtained using internal sequencing primers. The MrH4 coding region possesses a polypeptide of 103 amino acids with a calculated molecular weight of 11kDa and an isoelectric point of 11.5. The bioinformatics analysis showed that the MrH4 polypeptide contains a H4 signature at (15)GAKRH(19). Multiple sequence alignment of MrH4 showed that the N-terminal (21-42) and C-terminal (87-101) antimicrobial peptide regions and the pentapeptide or H4 signature (15-19) are highly conserved including in humans. The phylogenetic tree formed two separate clades of vertebrate and invertebrate H4, wherein MrH4 was located within the arthropod monophyletic clade of invertebrate H4 groups. Three-dimensional model of MrH4 was established using I-TASSER program and the model was validated using Ramachandran plot analysis. Schiffer-Edmundson helical wheel modeling was used to predict the helix propensity of N (21-42) and C (87-101) terminal derived Mr peptides. The highest gene expression was observed in gills and is induced by viral [white spot syndrome baculovirus (WSBV) and M. rosenbergii nodovirus (MrNV)] and bacterial (Aeromonas hydrophila and Vibrio harveyi) infections. The N and C terminal peptides were synthesized and their antimicrobial and hemolytic properties were examined. Both peptides showed activity against the tested Gram negative and Gram positive bacteria; however, the highest activity was noticed against Gram negative bacteria. Among the two peptides used in this study, C-terminal peptide yielded better results than the N-terminal peptide. Therefore, C terminal

Bis(tetramethylcyclopentadienyl)titanium chemistry. Molecular structures of [(C(5)HMe(4))(mu-eta(1) : eta(5)-C(5)Me(4))Ti](2) and [(C(5)HMe(4))(2)Ti]N-2(2)

NARCIS (Netherlands)

deWolf, JM; Blaauw, R; Meetsma, A; Teuben, JH; Gyepes, R; Varga, [No Value; Mach, K; Veldman, N; Spek, AL

1996-01-01

Thermolysis of bis(tetramethylcyclopentadienyl)-stabilized titanium(III) compounds (C(5)HMe(4))(2)TiR (R = Me (2), Ph (3)) yields, in marked contrast with the bis(pentamethylcyclopentadienyl) analog, the dimeric product [(C(5)HMe(4))(mu-eta(1):eta(5)-C(5)Me(4))Ti](2) (4), With a bridging metalated

Bis[μ-2,5-bis(pyridin-2-yl-1,3,4-thiadiazole-κ4N2,N3:N4,N5]bis[(nitrato-κOsilver(I] tetrahydrate

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Abdelhakim Laachir

2013-06-01

Full Text Available The self-assembly of an angular 2,5-bis(pyridin-2-yl-1,3,4-thiadiazole ligand (L with silver nitrate (AgNO3 produced a new dinuclear silver(I coordination complex, [Ag2(C12H8N4S2(NO32]·4H2O, which crystallizes with two Ag atoms bridged by two L ligands. The Ag atom is surrounded by four N atoms of L and by one O from the nitrate anion defining a distorted square pyramid. The atoms comprising the dication are nearly coplanar, with an r.m.s. deviation of 0.1997 Å. Molecules are linked by C—H...O and O—H...O hydrogen bonds through nitrate anions and water molecules, forming a two-dimensional porous network. The overall structure involves stacking of Ag complex layers along the b axis. The cohesion in the three-dimensional architecture is ensured by O...Ag interactions.

Synergy between the N-terminal and C-terminal domains of Mycobacterium tuberculosis HupB is essential for high-affinity binding, DNA supercoiling and inhibition of RecA-promoted strand exchange.

Science.gov (United States)

Sharadamma, N; Khan, Krishnendu; Kumar, Sandeep; Patil, K Neelakanteshwar; Hasnain, Seyed E; Muniyappa, K

2011-09-01

The occurrence of DNA architectural proteins containing two functional domains derived from two different architectural proteins is an interesting emerging research theme in the field of nucleoid structure and function. Mycobacterium tuberculosis HupB, unlike Escherichia coli HU, is a two-domain protein that, in the N-terminal region, shows broad sequence homology with bacterial HU. The long C-terminal extension, on the other hand, contains seven PAKK/KAAK motifs, which are characteristic of the histone H1/H5 family of proteins. In this article, we describe several aspects of HupB function, in comparison with its truncated derivatives lacking either the C-terminus or N-terminus. We found that HupB binds a variety of DNA repair and replication intermediates with K(d) values in the nanomolar range. By contrast, the N-terminal fragment of M. tuberculosis HupB (HupB(MtbN)) showed diminished DNA-binding activity, with K(d) values in the micromolar range, and the C-terminal domain was completely devoid of DNA-binding activity. Unlike HupB(MtbN) , HupB was able to constrain DNA in negative supercoils and introduce negative superhelical turns into relaxed DNA. Similarly, HupB exerted a robust inhibitory effect on DNA strand exchange promoted by cognate and noncognate RecA proteins, whereas HupB(MtbN), even at a 50-fold molar excess, had no inhibitory effect. Considered together, these results suggest that synergy between the N-terminal and C-terminal domains of HupB is essential for its DNA-binding ability, and to modulate the topological features of DNA, which has implications for processes such as DNA compaction, gene regulation, homologous recombination, and DNA repair. © 2011 The Authors Journal compilation © 2011 FEBS.

Induction of c-Jun by air particulate matter (PM₁₀) of Mexico city: Participation of polycyclic aromatic hydrocarbons.

Science.gov (United States)

Salcido-Neyoy, Martha Estela; Sánchez-Pérez, Yesennia; Osornio-Vargas, Alvaro Román; Gonsebatt, María Eugenia; Meléndez-Zajgla, Jorge; Morales-Bárcenas, Rocío; Petrosyan, Pavel; Molina-Servin, Edith Danny; Vega, Elizabeth; Manzano-León, Natalia; García-Cuellar, Claudia M

2015-08-01

The carcinogenic potential of urban particulate matter (PM) has been partly attributed to polycyclic aromatic hydrocarbons (PAHs) content, which activates the aryl hydrocarbon receptor (AhR). Here we report the effect of PM with an aerodynamic size of 10 μm (PM10) on the induction of AhR pathway in A549 cells, evaluating its downstream targets CYP1B1, IL-6, IL-8 and c-Jun. Significant increases in CYP1B1 protein and enzyme activity; IL-6 and IL-8 secretion and c-Jun protein were found in response to PM10. The formation of PAH-DNA adducts was also detected. The involvement of AhR pathway was confirmed with Resveratrol as AhR antagonist, which reversed CYP1B1 and c-Jun induction. Nevertheless, in IL-6 and IL-8 secretion, the Resveratrol was ineffective, suggesting an effect independent of this pathway. Considering the role of c-Jun in oncogenesis, its induction by PM may be contributing to its carcinogenic potential through induction of AhR pathway by PAHs present in PM10. Copyright © 2015 Elsevier Ltd. All rights reserved.

Interferon-β-induced activation of c-Jun NH2-terminal kinase mediates apoptosis through up-regulation of CD95 in CH31 B lymphoma cells

International Nuclear Information System (INIS)

Takada, Eiko; Shimo, Kuniaki; Hata, Kikumi; Abiake, Maira; Mukai, Yasuo; Moriyama, Masami; Heasley, Lynn; Mizuguchi, Junichiro

2005-01-01

Type I interferon (IFN)-induced antitumor action is due in part to apoptosis, but the molecular mechanisms underlying IFN-induced apoptosis remain largely unresolved. In the present study, we demonstrate that IFN-β induced apoptosis and the loss of mitochondrial membrane potential (ΔΨm) in the murine CH31 B lymphoma cell line, and this was accompanied by the up-regulation of CD95, but not CD95-ligand (CD95-L), tumor necrosis factor (TNF), or TNF-related apoptosis-inducing ligand (TRAIL). Pretreatment with anti-CD95-L mAb partially prevented the IFN-β-induced loss of ΔΨm, suggesting that the interaction of IFN-β-up-regulated CD95 with CD95-L plays a crucial role in the induction of fratricide. IFN-β induced a sustained activation of c-Jun NH 2 -terminal kinase 1 (JNK1), but not extracellular signal-regulated kinases (ERKs). The IFN-β-induced apoptosis and loss of ΔΨm were substantially compromised in cells overexpressing a dominant-negative form of JNK1 (dnJNK1), and it was slightly enhanced in cells carrying a constitutively active JNK construct, MKK7-JNK1 fusion protein. The IFN-β-induced up-regulation of CD95 together with caspase-8 activation was also abrogated in the dnJNK1 cells while it was further enhanced in the MKK7-JNK1 cells. The levels of cellular FLIP (c-FLIP), competitively interacting with caspase-8, were down-regulated by stimulation with IFN-β but were reversed by the proteasome inhibitor lactacystin. Collectively, the IFN-β-induced sustained activation of JNK mediates apoptosis, at least in part, through up-regulation of CD95 protein in combination with down-regulation of c-FLIP protein

Proinflammatory effect of sodium 4-phenylbutyrate in deltaF508-cystic fibrosis transmembrane conductance regulator lung epithelial cells: involvement of extracellular signal-regulated protein kinase 1/2 and c-Jun-NH2-terminal kinase signaling.

Science.gov (United States)

Roque, Telma; Boncoeur, Emilie; Saint-Criq, Vinciane; Bonvin, Elise; Clement, Annick; Tabary, Olivier; Jacquot, Jacky

2008-09-01

Sodium 4-phenylbutyrate (4-PBA) has attracted a great deal of attention in cystic fibrosis (CF) pathology due to its capacity to traffic DeltaF508-cystic fibrosis transmembrane conductance regulator (CFTR) to the cell membrane and restore CFTR chloride function at the plasma membrane of CF lung cells in vitro and in vivo. Using two different DeltaF508-CFTR lung epithelial cell lines (CFBE41o- and IB3-1 cells, characterized with DeltaF508-homozygous and heterozygous genotype, respectively) in vitro, 4-PBA induced an increase of proinflammatory cytokine interleukin (IL)-8 production in a concentration-dependent manner. This 4-PBA-induced IL-8 production was associated with a strong reduction of proteasome and nuclear factor-kappaB transcriptional activities in the two DeltaF508-CFTR lung cells either in a resting state or after tumor necrosis factor-alpha stimulation. In contrast, a strong increase of activator protein-1 transcriptional activity was observed. The inhibition of extracellular signal-regulated protein kinase 1/2 (ERK1/2) by 1,4-diamino-2,3-dicyano-1,4-bis[2-aminophenylthio] butadiene (U0126) and 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one (PD98059) and c-Jun-NH(2)-terminal kinase (JNK) mitogen-activated protein kinase (MAPK) by anthra[1,9-cd] pyrazol-6 (2H)-one (SP600125), respectively, was associated with a reduction (2-3.5-fold) of IL-8 production in both DeltaF508-CFTR lung cell lines treated with 4-PBA. No significant change of IL-8 production was observed after an inhibition of p38 MAPK with 4-[4-(4-fluorophenyl)-5-(4-pyridinyl)-1H-imidazol-2-yl] phenol (SB202190). Therefore, we suggest that inhibition of both ERK1/2 and JNK signaling may be a means to strongly reduce 4-PBA-induced IL-8 production in combination with 4-PBA treatment to restore CFTR Cl(-) channel function in lung epithelial cells of patients with CF.

Acoplamiento molecular y actividad antibacteriana de las tioureas (R,R-N,N´-bis(1-ciclohexiletiltiourea y (R,R-N,N´-bis(1-feniletiltiourea

Directory of Open Access Journals (Sweden)

Fabían Martínez Flores

2013-05-01

Full Text Available Las tioureas, son compuestos resultantes de sustituir el átomo de oxígeno de la urea (NH2CONH2 por un átomo de azufre (NH2CSNH2. Actualmente se ha visto que las tioureas presentan diversas actividades biológicas, dentro de las que se encuentra la antimicrobiana. En el presente estudio se evaluó la actividad antibacteriana mediante acoplamiento molecular entre la enzima DNA girasa (receptor y las tioureas (R, R-N,N´-bis(1 ciclohexiletiltiourea (CYTU1 y (R,R-N,N´-bis(1-feniletiltiourea (CYTU2 como ligando en busca del posible mecanismo de acción de estos compuestos, los resultados muestran que existe interacción entre la enzima y ambas tioureas en el sitio activo. Por otro lado, también se evaluó la actividad antibacteriana frente a cepas de Sthapylococcus aureus, Escherichia coli y Pseudomonas fluorescens, mediante el método de microdilución en caldo con la adición de bromuro de 3-(4,5-dimetil-2-tiazolil-2,5-difeniltetrazolium (MTT, como parte del ensayo de viabilidad, mostrando una disminución de la misma sólo contra las bacterias gram negativas, siendo la tiourea CYTU2 la que mostró mejor actividad antibacteriana. Molecular docking and antibacterial activity thioureas (R,R-N,N´-bis(1-cyclohexyethylthiourea and (R,R-N,N´-bis(1-phenylethylthiourea Abstract Thioureas are resultant compounds of substitute the oxygen atom from urea (NH2CONH2 for a sulfur atom (NH2CSNH2. There are evidential that show the biological activity of thioureas, within which are antibacterial activity. We studied the antibacterial activity of two thioureas (R,R-N,N´-bis(1 cyclohexylethylthiourea (CYTU1 y (R,R-N,N´-bis(1 phenylethylthiourea (CYTU2 in silico using Molecular Docking between the DNA gyrase enzyme (receptor and the two thioureas (ligand. The results showed interaction between DNA girase and both thioureas on the pocket of the enzyme. By other hand, the biological activity was evaluated against the following bacterial strains: Sthapylococcus

Supervisión pedagógica y gestión institucional en la calidad educativa de la Institución Educativa "Glorioso Húsares de Junín" El Agustino-2016

OpenAIRE

Tripul Escobedo, Elena del Pilar

2017-01-01

La investigación presentó como propósito determinar la influencia Supervisión Pedagógica y Gestión Institucional en la calidad educativa de la Institución Educativa "Glorioso Húsares de Junín" El Agustino-2016. Dicho estudio empleo la metodología descriptiva de diseño no experimental, transversal. La población estuvo constituida por los docentes de la Institución Educativa "Glorioso Húsares de Junín" El Agustino-2016. Se utilizó el muestreo no probabilístico de carácter cens...

catena-Poly[[[diaquabis(selenocyanato-κNiron(II]-μ-1,2-bis(pyridin-4-ylethane-κ2N:N′] 1,2-bis(pyridin-4-ylethane disolvate dihydrate

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Susanne Wöhlert

2013-06-01

Full Text Available The title compound, {[Fe(NCSe2(C12H12N2(H2O2]·2C12H12N2·2H2O}n, was obtained by the reaction of iron(II sulfate heptahydrate and potassium selenocyanate with 1,2-bis(pyridin-4-ylethane (bpa in water. The FeII cation is coordinated by two N-bonded selenocyanate anions, two water molecules and two 1,2-bis(pyridin-4-ylethane (bpa ligands in a slightly distorted octahedral geometry. In addition, two non-coordinating bpa molecules and two water molecules are present. The FeII cation is located on a center of inversion while the coordinating bpa ligand is located on a twofold rotation axis. The FeII cations are linked by the bpa ligands into chains along the b-axis direction, which are further connected into layers perpedicular to the c axis by O—H...N and O—H...O hydrogen bonds to the non-coordinating bpa and the water molecules. The crystal studied was twinned by pseudo-merohedry (180° rotation along c*; contribution of the minor twin component 3.7%.

Prostaglandin E2 stimulates normal bronchial epithelial cell growth through induction of c-Jun and PDK1, a kinase implicated in oncogenesis.

Science.gov (United States)

Fan, Yu; Wang, Ye; Wang, Ke

2015-12-18

Cyclooxygenase-2-derived prostaglandin E2 (PGE2), a bioactive eicosanoid, has been implicated in many biological processes including reproduction, inflammation and tumor growth. We previously showed that PGE2 stimulated lung cancer cell growth and progression through PGE2 receptor EP2/EP4-mediated kinase signaling pathways. However, the role of PGE2 in controlling lung airway epithelial cell phenotype remains unknown. We evaluated the effects of c-Jun and 3-phosphoinositede dependent protein kinase-1 (PDK1) in mediating epithelial cell hyperplasia induced by PGE2. The bronchial epithelial cell lines BEAS-2B and HBEc14-KT were cultured and then treated with PGE2. PDK1 small interfering RNA (siRNA) and a PDK1 inhibitor, an antagonist of the PGE2 receptor subtype EP4 and EP4 siRNA, c-Jun siRNA, and overexpressions of c-Jun and PDK1 have been used to evaluate the effects on cell proliferation. We demonstrated that PGE2 increased normal bronchial epithelial cell proliferation through induction of PDK1, an ankyrin repeat-containing Ser/Thr kinase implicated in the induction of apoptosis and the suppression of tumor growth. PDK1 siRNA and a PDK1 inhibitor blocked the effects of PGE2 on normal cell growth. The PGE2-induced PDK1 expression was blocked by an antagonist of the PGE2 receptor subtype EP4 and by EP4 siRNA. In addition, we showed that induction of PDK1 by PGE2 was associated with induction of the transcription factor, c-Jun protein. Silencing of c-Jun using siRNA and point mutations of c-Jun sites in the PDK1 gene promoter resulted in blockade of PDK1 expression and promoter activity induced by PGE2. In contrast, overexpression of c-Jun induced PDK1 gene promoter activity and expression followed increased cell proliferation. PGE2 increases normal bronchial epithelial cell proliferation through increased PDK1 gene expression that is dependent on EP4 and induction of c-Jun. Therewith, our data suggest a new role of c-Jun and PDK1 in mediating epithelial cell

Effects of interleukin-7/interleukin-7 receptor on RANKL-mediated osteoclast differentiation and ovariectomy-induced bone loss by regulating c-Fos/c-Jun pathway.

Science.gov (United States)

Zhao, Ji-Jun; Wu, Zhao-Feng; Yu, Ying-Hao; Wang, Ling; Cheng, Li

2018-09-01

To explore the effects of IL-7/IL-7R on the RANKL-mediated osteoclast differentiation in vitro and OVX-induced bone loss in vivo. BMMs and RAW264.7 were transfected with IL-7, IL-7R siRNA, c-Fos siRNA, and c-jun siRNA and later stimulated by RANKL. TRAP and toluidine blue staining were used to observe osteoclast formation and bone resorption, respectively. HE and TRAP staining were used to detect trabecular bone microstructure and osteoclasts of mice, respectively. qRT-PCR and Western blot analysis were used to examine expression. IL-7 unregulated the expression of CTSK, NFATc1, MMP9, and the phosphorylation of p38 and Akt by activating the c-Fos/c-Jun pathway, which increased osteoclast numbers and bone resorption in RANKL-stimulated macrophages. While IL-7R siRNA and c-Fos siRNA decreased the expression, as well as and the phosphorylation of p38 and Akt.IL-7 decreased the BMD and OPG expression in OVX-induced mice and increased the TRAP positive cells, the mRNA expression of c-fos, c-jun, and RANKL, which was contradictory to IL-7R siRNA, and c-Fos siRNA. Furthermore, IL-7R siRNA and c-Fos siRNA caused thicker trabeculae, increased trabecular number, and decreased osteolysis in OVX mice. IL-7/IL-7R can promote RANKL-mediated osteoclast formation and bone resorption by activating the c-Fos/c-Jun pathway, as well as inducing bone loss in OVX mice. © 2018 Wiley Periodicals, Inc.

The preparation and characterization of Cu(II complexes with N,N’,N”,N’”-tetrakis(2-pyridylmethyl-1,4,8,11-tetraazacyclotetradecane and 2,6-diacetylpyridine bis(semi/thiosemicarbazones

Directory of Open Access Journals (Sweden)

GORDANA VUCKOVIC

2004-03-01

Full Text Available Two new Cu(II mixed-ligand complexes with octadentate N,N’,N”,N’”-tetrakis(2-pyridylmethyl-1,4,8,11-tetraazacyclotetradecane (tpmc and potentially pentadentate ligands 2,6-diacetylpyridine bis(semicarbazone (DAPsc2 or 2,6-diacetylpyridine bis(thiosemicarbazone (DAPtsc2 were prepared. The general formulas: [Cu4 DAPsc2(tpmc2]ClO48·5CH3COCH3·H2O and [Cu2 DAPtsc2(tpmc](ClO44·7C2H5OH were proposed on the basis of elemental analyses and conductometric measurements. The complexes were characterized by magnetic measurement, electronic absorption and IR spectroscopy. For the dinuclear complex, an exo coordination of Cu(II with four nitrogens from tpmc and m-bonded DAPtsc2 through sulfurs and possibly terminal hydrazinic (azomethine nitrogens is assumed. For the tetranuclear complex, it is supposed that one DAPsc2 bridges two [Cu2 tpmc]4+ units using oxygens and terminal hydrazinic nitrogens as ligators. Finally, some antibacterial activity of the complexes was found.

Differential Effects of Ethanol on c-Jun N-Terminal Kinase, 14-3-3 Proteins, and Bax in Postnatal Day 4 and Postnatal Day 7 Rat Cerebellum

Science.gov (United States)

Heaton, Marieta Barrow; Paiva, Michael; Kubovic, Stacey; Kotler, Alexandra; Rogozinski, Jonathan; Swanson, Eric; Madorsky, Vladimir; Posados, Michelle

2011-01-01

These studies investigated ethanol effects on upstream cellular elements and interactions which contribute to Bax-related apoptosis in neonatal rat cerebellum at ages of peak ethanol sensitivity (postnatal day 4 [P4]), compared to later ages of relative resistance (P7). Analyses were made of basal levels of the pro-apoptotic c-jun N-termimal kinase (JNK), Bax, and the 14-3-3 anchoring proteins, as well as the responsiveness of these substances to ethanol at P4 versus P7. Dimerization of Bax with 14-3-3 was also investigated at the two ages following ethanol treatment, a process which sequesters Bax in the cytosol, thus inhibiting its mitochondrial translocation and disruption of the mitochondrial membrane potential. Cultured cerebellar granule cells were used to examine the protective potential of JNK inhibition on ethanol-mediated cell death. Basal levels of JNK were significantly higher at P4 than P7, but no differences in the other proteins were found. Activated JNK, and cytosolic and mitochondrially-translocated Bax were increased in P4 but not P7 animals following ethanol exposure, while protective 14-3-3 proteins were increased only at P7. Ethanol treatment resulted in decreases in Bax:14-3-3 heterodimers at P4, but not at P7. Inhibition of JNK activity in vitro provided partial protection against ethanol neurotoxicity. Thus, differential temporal vulnerability to ethanol in this CNS region correlates with differences in both levels of apoptosis-related substances (e.g., JNK), and differential cellular responsiveness, favoring apoptosis at the most sensitive age and survival at the resistant age. The upstream elements contributing to this vulnerability can be targets for future therapeutic strategies. PMID:22169498

Transformation mechanism of n-butyl terminated Si nanoparticles embedded into Si1-xCx nanocomposites mixed with Si nanoparticles and C atoms

International Nuclear Information System (INIS)

Shin, J.W.; Oh, D.H.; Kim, T.W.; Cho, W.J.

2009-01-01

Bright-field transmission electron microscopy (TEM) images, high-resolution TEM (HRTEM) images, and fast-Fourier transformed electron-diffraction patterns showed that n-butyl terminated Si nanoparticles were aggregated. The formation of Si 1-x C x nanocomposites was mixed with Si nanoparticles and C atoms embedded in a SiO 2 layer due to the diffusion of C atoms from n-butyl termination shells into aggregated Si nanoparticles. Atomic force microscopy (AFM) images showed that the Si 1-x C x nanocomposites mixed with Si nanoparticles and C atoms existed in almost all regions of the SiO 2 layer. The formation mechanism of Si nanoparticles and the transformation mechanism of n-butyl terminated Si nanoparticles embedded into Si 1-x C x nanocomposites mixed with Si nanoparticles and C atoms are described on the basis of the TEM, HRTEM, and AFM results. These results can help to improve the understanding of the formation mechanism of Si nanoparticles.

Adsorption and surface reaction of bis-diethylaminosilane as a Si precursor on an OH-terminated Si (0 0 1) surface

International Nuclear Information System (INIS)

Baek, Seung-Bin; Kim, Dae-Hee; Kim, Yeong-Cheol

2012-01-01

The adsorption and the surface reaction of bis-diethylaminosilane (SiH 2 [N(C 2 H 5 ) 2 ] 2 , BDEAS) as a Si precursor on an OH-terminated Si (0 0 1) surface were investigated to understand the initial reaction mechanism of the atomic layer deposition (ALD) process using density functional theory. The bond dissociation energies between two atoms in BDEAS increased in the order of Si-H, Si-N, and the rest of the bonds. Therefore, the relatively weak Si-H and Si-N bonds were considered for bond breaking during the surface reaction. Optimum locations of BDEAS for the Si-H and Si-N bond breaking were determined on the surface, and adsorption energies of 0.43 and 0.60 eV, respectively, were obtained. The Si-H bond dissociation energy of the adsorbed BDEAS on the surface did not decrease, so that a high reaction energy barrier of 1.60 eV was required. On the other hand, the Si-N bond dissociation energy did decrease, so that a relatively low reaction energy barrier of 0.52 eV was required. When the surface reaction energy barrier was higher than the adsorption energy, BDEAS would be desorbed from the surface instead of being reacted. Therefore, the Si-N bond breaking would be dominantly involved during the surface reaction, and the result is in good agreement with the experimental data in the literature.

Intrinsic structural differences in the N-terminal segment of pulmonary surfactant protein SP-C from different species

DEFF Research Database (Denmark)

Plasencia, I; Rivas, L; Casals, C

2001-01-01

Predictive studies suggest that the known sequences of the N-terminal segment of surfactant protein SP-C from animal species have an intrinsic tendency to form beta-turns, but there are important differences on the probable location of these motifs in different SP-C species. Our hypothesis...

'Pincer' dicarbene complexes of some early transition metals and uranium.

Science.gov (United States)

Pugh, David; Wright, Joseph A; Freeman, Sandra; Danopoulos, Andreas A

2006-02-14

The complexes [(C-N-C)MX(n)(thf)(m)] with the 'pincer' 2,6-bis(imidazolylidene)pyridine, (C-N-C) = 2,6-bis(arylimidazol-2-ylidene)pyridine, aryl = 2,6-Pr(i)2C6H3, M = V, X = Cl, n = 2, m = 1 1a; M = Cr, X = Cl, n = 2, m = 0, 2a, X = Br, 2b; M = Mn, X = Br, n = 2, m = 0, 3; M = Nb, X = Cl, n = 3, m = 0, 4; and M = U, X = Cl, n = 4, m = 0, 5, were synthesised by (a) substitution of labile tmed (1a), thf (2a, 3, 5) or dme (4) by free (C-N-C) or by (b) reaction of the bisimidazolium salt (CH-N-CH)Br2 with {Cr[N(SiMe3)2]2(thf)2} followed by amine elimination (2b). Attempted alkylation of 1a, 2, 3a and 4 with Grignard or alkyl lithiums gave intractable mixtures, and in one case [reaction of 1a with (mesityl)MgBr] resulted in exchange of Cl by Br (1b). Oxidation of 1a or [(C-N-C)VCl3] with 4-methylmorpholine N-oxide afforded the trans-V(C-N-C)(=O)Cl2, 6, which by reaction with AgBF4 in MeCN gave trans-[V(C-N-C)(=O)(MeCN)2][BF4]2, 7. Reaction of 1a with p-tolyl azide gave trans-V(C-N-C)(=N-p-tolyl)Cl2 8. The complex trans-Ti(C-N-C)(=NBu(t))Cl2, 9, was prepared by substitution of the pyridine ligands in Ti(NBu(t))Cl2(py)3 by C-N-C.

Reação de bis-inserção de 1,2-difenilacetileno na ligação Pd-C de ciclometalados Bis insertion reaction of 1,2-diphenylacetilene into Pd-C bond of cyclometallated species

Directory of Open Access Journals (Sweden)

Sandra Regina Ananias

2003-01-01

Full Text Available The present paper deals with the bis-insertion reactions of 1,2-diphenylacetylene into Pd-C bond of the cyclopalladated complexes [Pd(dmba(µ-NCO]2 (1 and [Pd(dmba(MeCN2](NO3 (2 (dmba = N,N-dimethylbenzylamine, MeCN = acetonitrile. Two new complexes [Pd{PhC=CPh-CPh=CPhC6H4CH2N(CH 32}(NCO] (3 and [Pd{PhC=CPh-CPh=CPhC6H4CH2N(CH 32}(NO3 ] (4 were obtained and characterized by IR and NMR spectroscopy and elemental analysis.

Adaptación y validación española de la Escala de Impulsividad de Barratt en adolescentes tempranos (BIS-11-A

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Víctor Martínez-Loredo

2015-01-01

Full Text Available La impulsividad ha sido relacionada con multitud de trastornos psiquiátricos como el abuso de sustancias. La Escala de Impulsividad de Barratt (BIS-11 es uno de los autoinformes más comúnmente administrados para la evaluación de la impulsividad, tanto en el ámbito clínico como de investigación. Hay una versión para adolescentes llamada BIS- 11-A, que aún no ha sido convenientemente adaptada a población española. El objetivo de este estudio es ofrecer una versión española alternativa y más adecuada del BIS-11-A, así como la evaluación de sus características psicométricas tales como estructura factorial, fiabilidad y validez predictiva sobre el uso de sustancias (uso en el último mes de alcohol, tabaco y cánnabis, presencia de borracheras en el último mes, consumo intensivo y problemático de alcohol. El BIS-11-A e ítems de la Encuesta Escolar Europea sobre Alcohol y otras Drogas (ESPAD fueron aplicados a 1.183 estudiantes (edad 12-14 años en 16 institutos españoles de educación secundaria. El BIS-11-A ha mostrado una estructura bidimensional, alta fiabilidad (alfa de Cronbach = 0,87 y buena capacidad para identificar el uso de sustancias, consumo intensivo y problemático de alcohol (sensibilidad = 67,3-75%; especificidad = 83,4-85,4%. La versión española del BIS-11-A es un instrumento fiable y válido para su uso con adolescentes tempranos.

Sterically crowded monomeric neutral bis(benzamidinato) compounds of aluminium, [PhC(NSiMe(3))(2)](2)AlX (X=Cl, H); X-ray crystal structure of [PhC(NSiMe(3))(2)]2AlH

NARCIS (Netherlands)

Duchateau, R; Meetsma, A; Teuben, JH

1996-01-01

AlCl3 reacts with [PhC(NSiMe(3))(2)]Li(OEt(2)) to afford the bis(N,N'-bis(trimethylsilyl)benzamidinato)aluminium chloro compound which, on treatment with KBEt(3)H, yields the structurally characterized monomeric hydride derivative, [PhC(NSiMe(3))(2)]2AlH, whose reactivity towards unsaturated

Alternativas legales para negociación de la quinua de pequeños productores en la región Junín

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Ricardo Solis Reategui

2015-06-01

Full Text Available El objetivo del presente trabajo es mostrar la situación de los pequeños productores de quinua de la región Junín y como la implementación que ya se ha dado en otras partes del país podrían mejorar su entorno con el uso de herramientas legales que podrían asegurar sus producciones a mejores precios y con mejor trato al productor original. Para la recopilación de la información se recurrió a la revisión de literatura especializada. Entre los hallazgos se puede mencionar que los pequeños productores expresan que los acopiadores y las empresas exportadoras no muestran interés alguno en apoyarlos. Para ellos el fin de los acopiadores y el exportador es lucrar a través de conseguir un menor precio en el productor. Entre las conclusiones del trabajo se puede mencionar que existe muy poca asociatividad en la región Junín, algunas instituciones del Estado y regionales apoyan el desarrollo asociativo pero de manera incipiente y con muy poca información. La quinua de la región Junín es considerada orgánica, y el precio que se paga por ella es bastante bajo respecto de la calidad de la misma comparativamente con la quinua de la costa, que trata de alcanzar el mismo precio pero con una producción intensiva con el uso de pesticidas y bioquímicos que limitan su ingreso a determinados mercados. Las autoridades locales y regionales deben ayudar a desarrollar pequeñas cadenas para mejorar la producción de quinua a través de asesoría técnica, consecuentemente un buen producto permitirá exigir un mejor precio y condiciones de pago.

Synergistic extraction of Eu(III) with N-phosphorylated bis-ureas and chlorinated cobalt bis(dicarbollide) ion

Czech Academy of Sciences Publication Activity Database

Selucký, P.; Bubeníková, M.; Rais, J.; Grüner, Bohumír; Brusko, V.V.

2013-01-01

Roč. 101, č. 1 (2013), s. 27-31 ISSN 0033-8230 R&D Projects: GA ČR GA104/09/0668 Institutional support: RVO:61388980 Keywords : liquid-liquid extraction * lanthanides * actinides * N-phosphorylated bis-ureas * chlorinated cobalt bis(dicarbollide) ion * high level liquid waste Subject RIV: CA - Inorganic Chemistry Impact factor: 1.411, year: 2013

Synergistic extraction of Eu(III) with N-phosphorylated bis-ureas and chlorinated cobalt bis(dicarbollide) ion

Energy Technology Data Exchange (ETDEWEB)

Selucky, P.; Bubenikova, M.; Rais, J. [UJV Rez, a.s., Rez near Prague (Czech Republic); Gruener, B. [Academy of Sciences of the Czech Republic, Rez near Prague (Czech Republic). Inst. of Inorganic Chemistry; Brusko, V.V. [JSC NIIneftepromchim, Kazan (Russian Federation)

2013-03-01

Extraction of Eu(III) with a synergistic mixture of polydentate N-phosphorylated bis-ureas with the general formula (i-PrO){sub 2}P(O)NHC(O)NHXNHC(O)NHP(O)(Oi-Pr){sub 2} (X = (CH{sub 2}){sub 7}, (CH{sub 2}){sub 2}O(CH{sub 2}){sub 2} and (CH{sub 2}){sub 2}O(CH{sub 2}){sub 2}O(CH{sub 2}){sub 2}) and chlorinated cobalt bis(dicarbollide) ion (CCD-) with formula closo-[(1,2-C{sub 2}B{sub 9}H{sub 8}Cl{sub 3}){sub 2}-3-Co]{sup -} was studied using nitrobenzene as the solvent. Extraction of Eu(III) was very effective up to high concentrations of nitric acid. Eu(III) is most likely extracted into the organic phase as the [EuL{sub 2}]{sup 3+} species whereas the positive charge of extracted complex is compensated by CCD and/or nitrate anions. (orig.)

Contribuciones hacia la cronología del Periodo Arcaico en las punas de Junín

OpenAIRE

Kaulicke, Peter

2012-01-01

Some Contributions to the Chronology of the Archaic Period in the Punas of JunínThe stratigraphy and the typology from the Uchkumachay excavations are presented as well as preliminary results of a comparative study undertaken in collaboration with D. Lavallée and M. Julien. These data bear major importance on the building of a general chronology and synthesis of the Archaic Period which still is missing for the Junín area in spite of being one of the best studied areas in the Central Andes fo...

Axon Termination, Pruning, and Synaptogenesis in the Giant Fiber System of Drosophila melanogaster Is Promoted by Highwire.

Science.gov (United States)

Borgen, Melissa; Rowland, Kimberly; Boerner, Jana; Lloyd, Brandon; Khan, Aruna; Murphey, Rodney

2017-03-01

The ubiquitin ligase Highwire has a conserved role in synapse formation. Here, we show that Highwire coordinates several facets of central synapse formation in the Drosophila melanogaster giant fiber system, including axon termination, axon pruning, and synaptic function. Despite the similarities to the fly neuromuscular junction, the role of Highwire and the underlying signaling pathways are distinct in the fly's giant fiber system. During development, branching of the giant fiber presynaptic terminal occurs and, normally, the transient branches are pruned away. However, in highwire mutants these ectopic branches persist, indicating that Highwire promotes axon pruning. highwire mutants also exhibit defects in synaptic function. Highwire promotes axon pruning and synaptic function cell-autonomously by attenuating a mitogen-activated protein kinase pathway including Wallenda, c-Jun N-terminal kinase/Basket, and the transcription factor Jun. We also show a novel role for Highwire in non-cell autonomous promotion of synaptic function from the midline glia. Highwire also regulates axon termination in the giant fibers, as highwire mutant axons exhibit severe overgrowth beyond the pruning defect. This excessive axon growth is increased by manipulating Fos expression in the cells surrounding the giant fiber terminal, suggesting that Fos regulates a trans -synaptic signal that promotes giant fiber axon growth. Copyright © 2017 by the Genetics Society of America.

The N-terminal segment of pulmonary surfactant lipopeptide SP-C has intrinsic propensity to interact with and perturb phospholipid bilayers

DEFF Research Database (Denmark)

Plasencia, Inés; Rivas, Luis; Keough, Kevin M W

2004-01-01

aggregation, and leakage of the aqueous content of the vesicles. The lipid-peptide interaction includes a significant hydrophobic component for both zwitterionic and anionic membranes, although the interaction with phosphatidylglycerol bilayers is also electrostatic in nature. The effects of the SP-C N......-terminal peptides on the membrane structure are mediated by significant perturbations of the packing order and mobility of phospholipid acyl chain segments deep in the bilayer, as detected by differential scanning calorimetry and spin-label ESR. These results suggest that the N-terminal region of SP-C, even...

Extraordinary photoluminescence behavior of an efficient electrochemiluminophore: Tb(III) chelated by 2,6-bis[N,N-bis(carboxymethyl)aminomethyl]-4-benzoylphenol

International Nuclear Information System (INIS)

Kuosmanen, Päivi; Pusa, Matti; Salminen, Kalle; Kulmala, Sakari

2016-01-01

The reactivities of lanthanide ions in their excited states are first considered in water and the energy diagrams of most important of them are sketched to illustrate the highly oxidizing and reducing species involved reacting with one-electron steps. Anomalous photoluminescence behavior of Tb(III) chelated by 2,6-bis[N,N-bis(carboxymethyl)aminomethyl]-4-benzoylphenol is studied. The present chelate is known to show relative strong chemiluminescence in the presence of hydrated electron and oxidizing radicals but it shows an extraordinarily short luminescence lifetime of radiative relaxation of its 5 D 4 state under photoexcitation.

Extraordinary photoluminescence behavior of an efficient electrochemiluminophore: Tb(III) chelated by 2,6-bis[N,N-bis(carboxymethyl)aminomethyl]-4-benzoylphenol

Energy Technology Data Exchange (ETDEWEB)

Kuosmanen, Päivi, E-mail: paivi.kuosmanen@aalto.fi; Pusa, Matti; Salminen, Kalle; Kulmala, Sakari

2016-05-15

The reactivities of lanthanide ions in their excited states are first considered in water and the energy diagrams of most important of them are sketched to illustrate the highly oxidizing and reducing species involved reacting with one-electron steps. Anomalous photoluminescence behavior of Tb(III) chelated by 2,6-bis[N,N-bis(carboxymethyl)aminomethyl]-4-benzoylphenol is studied. The present chelate is known to show relative strong chemiluminescence in the presence of hydrated electron and oxidizing radicals but it shows an extraordinarily short luminescence lifetime of radiative relaxation of its {sup 5}D{sub 4} state under photoexcitation.

PTEN C-Terminal Deletion Causes Genomic Instability and Tumor Development

Directory of Open Access Journals (Sweden)

Zhuo Sun

2014-03-01

Full Text Available Tumor suppressor PTEN controls genomic stability and inhibits tumorigenesis. The N-terminal phosphatase domain of PTEN antagonizes the PI3K/AKT pathway, but its C-terminal function is less defined. Here, we describe a knockin mouse model of a nonsense mutation that results in the deletion of the entire Pten C-terminal region, referred to as PtenΔC. Mice heterozygous for PtenΔC develop multiple spontaneous tumors, including cancers and B cell lymphoma. Heterozygous deletion of the Pten C-terminal domain also causes genomic instability and common fragile site rearrangement. We found that Pten C-terminal disruption induces p53 and its downstream targets. Simultaneous depletion of p53 promotes metastasis without influencing the initiation of tumors, suggesting that p53 mainly suppresses tumor progression. Our data highlight the essential role of the PTEN C terminus in the maintenance of genomic stability and suppression of tumorigenesis.

Using c-Jun to identify fear extinction learning-specific patterns of neural activity that are affected by single prolonged stress.

Science.gov (United States)

Knox, Dayan; Stanfield, Briana R; Staib, Jennifer M; David, Nina P; DePietro, Thomas; Chamness, Marisa; Schneider, Elizabeth K; Keller, Samantha M; Lawless, Caroline

2018-04-02

Neural circuits via which stress leads to disruptions in fear extinction is often explored in animal stress models. Using the single prolonged stress (SPS) model of post traumatic stress disorder and the immediate early gene (IEG) c-Fos as a measure of neural activity, we previously identified patterns of neural activity through which SPS disrupts extinction retention. However, none of these stress effects were specific to fear or extinction learning and memory. C-Jun is another IEG that is sometimes regulated in a different manner to c-Fos and could be used to identify emotional learning/memory specific patterns of neural activity that are sensitive to SPS. Animals were either fear conditioned (CS-fear) or presented with CSs only (CS-only) then subjected to extinction training and testing. C-Jun was then assayed within neural substrates critical for extinction memory. Inhibited c-Jun levels in the hippocampus (Hipp) and enhanced functional connectivity between the ventromedial prefrontal cortex (vmPFC) and basolateral amygdala (BLA) during extinction training was disrupted by SPS in the CS-fear group only. As a result, these effects were specific to emotional learning/memory. SPS also disrupted inhibited Hipp c-Jun levels, enhanced BLA c-Jun levels, and altered functional connectivity among the vmPFC, BLA, and Hipp during extinction testing in SPS rats in the CS-fear and CS-only groups. As a result, these effects were not specific to emotional learning/memory. Our findings suggest that SPS disrupts neural activity specific to extinction memory, but may also disrupt the retention of fear extinction by mechanisms that do not involve emotional learning/memory. Copyright © 2017 Elsevier B.V. All rights reserved.

Functional cooperation between HIF-1α and c-Jun in mediating primary and acquired resistance to gefitinib in NSCLC cells with activating mutation of EGFR.

Science.gov (United States)

Meng, Shuyan; Wang, Guorui; Lu, Yang; Fan, Zhen

2018-07-01

Hypoxia-inducible factor 1 (HIF-1) and activator protein 1 (AP-1) are important transcription factors regulating expression of genes involved in cell survival. HIF-1α and c-Jun are key components of HIF-1 and AP-1, respectively, and are regulated by epidermal growth factor receptor (EGFR)-mediated cell signaling and tumor microenvironmental cues. The roles of HIF-1α and c-Jun in development of resistance to EGFR tyrosine kinase inhibitor (TKI) in non-small cell lung cancer (NSCLC) with activating mutation of EGFR have not been explored. In this study, we investigated the roles of HIF-1α and c-Jun in mediating primary and acquired resistance to gefitinib in NSCLC cells with activating mutation of EGFR. Changes in HIF-1α protein and in total and phosphorylated c-Jun levels in relation to changes in total and phosphorylated EGFR levels before and after gefitinib treatment were measured using Western blot analysis in NSCLC cells sensitive or resistant to gefitinib. The impact of overexpression of a constitutively expressed HIF-1α (HIF-1α/ΔODD) or a constitutively active c-Jun upstream regulator (SEK1 S220E/T224D mutant) on cell response to gefitinib was also examined. The effect of pharmacological inhibition of SEK1-JNK-c-Jun pathway on cell response to gefitinib was evaluated. Downregulation of HIF-1α and total and phosphorylated c-Jun levels correlated with cell inhibitory response to gefitinib better than decrease in phosphorylated EGFR did in NSCLC cells with intrinsic or acquired resistance to gefitinib. Overexpression of HIF-1α/ΔODD or SEK1 S220E/T224D mutant conferred resistance to gefitinib. There exists a positive feed-forward regulation loop between HIF-1 and c-Jun. The JNK inhibitor SP600125 sensitized gefitinib-resistant NSCLC cells to gefitinib. HIF-1α and c-Jun functionally cooperate in development of resistance to gefitinib in NSCLC cells. The translational value of inhibiting HIF-1α/c-Jun cooperation in overcoming resistance to EGFR TKI

[N,N-Bis(2-aminoethylethane-1,2-diamine](ethane-1,2-diaminenickel(II thiosulfate trihydrate

Directory of Open Access Journals (Sweden)

Beatrix Seidlhofer

2012-02-01

Full Text Available The title compound, [Ni(C2H8N2(C6H18N4]S2O3·3H2O, was accidentally synthesized under solvothermal conditions applying [Ni(en3]Cl2 (en is ethane-1,2-diamine as the Ni source. The asymmetric unit consists of one discrete [Ni(tren(en]2+ complex [tren is N,N-bis(2-aminoethylethane-1,2-diamine] in which the Ni2+ cation is sixfold coordinated within a slightly distorted octahedron, one thiosulfate anion and three water molecules. In the crystal, the complex cations, anions and water molecules are linked by an intricate hydrogen-bonding network. One C atom of the tren ligand, as well as one O atom of a water molecule, are disordered over two sites and were refined using a split model (occupancy ratios = 0.85:15 and 0.60:0.40, respectively.

Pharmacokinetics of [14C]methylglyoxal-bis-guanylhydrazone) in patients with leukemia.

Science.gov (United States)

Rosenblum, M G; Keating, M J; Yap, B S; Loo, T L

1981-05-01

Methylglyoxal-bis(guanylhydrazone) (MGBG; NSC 32946), a competitive inhibitor of S-adenosyl-L-methionine decarboxylase (EC 4.1.1.50), currently being reevaluated for its clinical antileukemic activity. MGBG labeled with 14C in the guanylhydrazone moiety was administered i.v. (150 microCi; specific activity, 1.9 microCi/mumol; 20 mg total) to six patients with leukemia. All patients in the study had normal renal and hepatic function. [14C]MGBG underwent no in vivo metabolism; it disappeared from the plasma with an average terminal t 1/2 of 4.1 hr. The 72-hr cumulative urinary excretion was only 14.5 +/- 2.2% (S.E.M.) of the total radioactive dose. The apparent volume of distribution was 661 ml/kg and the total clearance rate was 21.2 ml/kg/min. The low urinary excretion rate and the relatively rapid plasma clearance suggest that MGBG may be sequestered in the body. Therefore, if MGBG is administered by a frequent treatment schedule, the prolonged biological half-life in humans may significantly contribute to its clinical toxicity.

Differential effects of v-Jun and c-Jun proteins on v-myb-transformed monoblasts

Czech Academy of Sciences Publication Activity Database

Ševčíková, S.; Souček, Karel; Kubala, Lukáš; Bryja, Vítězslav; Šmarda, J.

2002-01-01

Roč. 59, č. 10 (2002), s. 1690-1705 ISSN 1420-682X R&D Projects: GA ČR GA301/01/0040 Institutional research plan: CEZ:AV0Z5004920 Keywords : v-myb * Jun * differentiation Subject RIV: BO - Biophysics Impact factor: 5.259, year: 2002

μ-Carbonato-bis­(bis­{2-[(diethyl­amino)­meth­yl]phen­yl}bis­muth(III))

Science.gov (United States)

Soran, Albert P.; Nema, Mihai G.; Breunig, Hans J.; Silvestru, Cristian

2011-01-01

The mol­ecular structure of the title compound, [Bi2(C11H16N)4(CO3)], consists of a symmetrically bridging carbonato group which binds two [2-Et2NCH2C6H4]2Bi units that are crystallographically related via a twofold rotation axis bis­ecting the carbonate group. The two Bi atoms and two of the C atoms directly bonded to bis­muth are quasi-planar [deviations of 0.323 (1) and 0.330 (9)Å for the Bi and C atoms, respectively] with the carbonate group. The remaining two ligands are in a trans arrangement relative to the quasi-planar (CBi)2CO3 system. The metal atom is strongly coordinated by the N atom of one pendant arm [Bi—N = 2.739 (6) Å], almost trans to the O atom, while the N atom of the other pendant arm exhibits a weaker intra­molecular inter­action [Bi⋯N = 3.659 (7) Å] almost trans to a C atom. If both these intra­molecular N→Bi inter­actions per metal atom are considered, the overall coordination geometry at bis­muth becomes distorted square-pyramidal [(C,N)2BiO cores] and the compound can be described as a hypervalent 12-Bi-5 species. Additional quite short intra­molecular Bi⋯O inter­actions are also present [3.796 (8)–4.020 (9) Å]. Inter­molecular associations through weak η6⋯Bi inter­actions [Bi⋯centroid of benzene ring = 3.659 (1) Å] lead to a ribbon-like supra­molecular association. PMID:21522836

Immunohistological Analysis of the Jun Family and the Signal Transducers and Activators of Transcription in Thymus

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Alexandra Papoudou-Bai

2015-01-01

Full Text Available The Jun family and the signal transducers and activators of transcription (STAT are involved in proliferation and apoptosis. Moreover, c-Jun and STAT3 cooperate to regulate apoptosis. Therefore, we used double immunostaining to investigate the immunotopographical distribution of phospho-c-Jun (p-c-Jun, JunB, JunD, p-STAT3, p-STAT5, and p-STAT6 in human thymus. JunD was frequently expressed by thymocytes with higher expression in medullary compared to cortical thymocytes. p-c-Jun was frequently expressed by cortical and medullary thymic epithelial cells (TEC and Hassall bodies (HB. p-STAT3 was frequently expressed by TEC with higher expression in cortical compared to medullary TEC and HB. p-c-Jun, JunB, p-STAT3, p-STAT5, and p-STAT6 were rarely expressed by thymocytes. JunB and JunD were expressed by rare cortical TEC with higher expression in medullary TEC. p-STAT5 and p-STAT6 were expressed by rare cortical and medullary TEC. Double immunostaining revealed p-c-Jun and JunD expression in rare CD11c positive dendritic cells. Our findings suggest a notable implication of JunD in the physiology of thymocytes and p-c-Jun and p-STAT3 in the physiology of TEC. The diversity of the immunotopographical distribution and the expression levels of p-c-Jun, JunB, JunD, p-STAT3, p-STAT5, and p-STAT6 indicates that they are differentially involved in the differentiation of TEC, thymocytes, and dendritic cells.

N,N,N′,N′-Tetramethyl-N′′-[2-(trimethylazaniumylethyl]guanidinium bis(tetraphenylborate acetone disolvate

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Ioannis Tiritiris

2016-02-01

Full Text Available The asymmetric unit of the title solvated salt, C10H26N42+·2C24H20B−·2C3H6O, comprises one cation, two tetraphenylborate ions and two acetone solvent molecules. The N and methyl C atoms of the terminal trimethylammonium group are disordered over two sets of sites, with a refined occupancy ratio of 0.846 (3:0.154 (3. The C—N bond lengths in the central C3N unit of the guanidinium ion range between 1.3308 (16 and 1.3508 (16 Å, indicating a degree of double-bond character. The central C atom is bonded to the three N atoms in a nearly ideal trigonal–planar geometry and the positive charge is delocalized in the CN3 plane. The C—N bond lengths in the terminal trimethylammonium group have values close to that of a typical single bond, and the second positive charge is localized there. In the crystal, the guanidinium ion is connected by N—H...O and C—H...O hydrogen bonds with the acetone molecules. C—H...π interactions are present between the guanidinium H atoms and the phenyl rings of the tetraphenylborate ions, leading to the formation of a two-dimensional supramolecular pattern along the bc plane.

Photochemically activated antiviral halogenated 1,8-naphthalimides: synthesis of N,N'-bis-{2-[(5-bromo-2-[1-14C]hexyl-1H-benz[de]isoquinolin-1,3(2H)-dion-6-yl)amino]ethyl}hexanediamide

International Nuclear Information System (INIS)

Hayes, B.A.; Gupta, Surendra; Shaochieh Chang; Utecht, R.E.; Lewis, D.E.

1996-01-01

The synthesis of N,N'-bis-{2-[(5-bromo-2-[1- 14 C]hexyl-1H-benz[de]isoquinolin-1, 3(2H)-dion-6-yl)amino]ethyl}hexanediamide from 1-[1- 14 C]-hexylamine and 4-chloro-1,8-naphthalic anhydride is described. The anhydride is first converted to the 4-chloro-n-[1- 14 C]hexyl-1,8-naphthalimide by condensation with 1-[1- 14 C]-hexylamine, and the chlorine is then displaced with ethylenediamine to give the 4-(2-aminoethylamino-N-[1- 14 C]hexyl-1,8-naphthalimide. Coupling of this monomeric naphthalimide with adipoyl chloride affords the dimeric naphthalimide which is brominated regiospecifically with elemental bromine in carbon tetrachloride to afford the title compound. (author)

Vesicular transport route of horseradish C1a peroxidase is regulated by N- and C-terminal propeptides in tobacco cells.

Science.gov (United States)

Matsui, T; Nakayama, H; Yoshida, K; Shinmyo, A

2003-10-01

Peroxidases (PRX, EC 1.11.1.7) are widely distributed across microorganisms, plants, and animals; and, in plants, they have been implicated in a variety of secondary metabolic reactions. In particular, horseradish (Armoracia rusticana) root represents the main source of commercial PRX production. The prxC1a gene, which encodes horseradish PRX (HRP) C, is expressed mainly in the roots and stems of the horseradish plant. HRP C1a protein is shown to be synthesized as a preprotein with both a N-terminal (NTPP) and a C-terminal propeptide (CTPP). These propeptides, which might be responsible for intracellular localization or secretion, are removed before or concomitant with production of the mature protein. We investigated the functional role of HRP C1a NTPP and CTPP in the determination of the vesicular transport route, using an analytical system of transgenically cultured tobacco cells (Nicotiana tabacum, BY2). Here, we report that NTPP and CTPP are necessary and sufficient for accurate localization of mature HRP C1a protein to vacuoles of the vesicular transport system. We also demonstrate that HRP C1a derived from a preprotein lacking CTPP is shunted into the secretory pathway.

Oncoprotein protein kinase antibody kit

Science.gov (United States)

Karin, Michael [San Diego, CA; Hibi, Masahiko [San Diego, CA; Lin, Anning [La Jolla, CA

2008-12-23

An isolated polypeptide (JNK) characterized by having a molecular weight of 46 kD as determined by reducing SDS-PAGE, having serine and threonine kinase activity, phosphorylating the c-Jun N-terminal activation domain and polynucleotide sequences and method of detection of JNK are provided herein. JNK phosphorylates c-Jun N-terminal activation domain which affects gene expression from AP-1 sites.

Fibroin and sericin from Bombyx mori silk stimulate cell migration through upregulation and phosphorylation of c-Jun.

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Celia Martínez-Mora

Full Text Available Wound healing is a biological process directed to the restoration of tissue that has suffered an injury. An important phase of wound healing is the generation of a basal epithelium able to wholly replace the epidermis of the wound. A broad range of products derived from fibroin and sericin from Bombyx mori silk are used to stimulate wound healing. However, so far the molecular mechanism underlying this phenomenon has not been elucidated. The aim of this work was to determine the molecular basis underlying wound healing properties of silk proteins using a cell model. For this purpose, we assayed fibroin and sericin in a wound healing scratch assay using MDA-MB-231 and Mv1Lu cells. Both proteins stimulated cell migration. Furthermore, treatment with sericin and fibroin involved key factors of the wound healing process such as upregulation of c-Jun and c-Jun protein phosphorylation. Moreover, fibroin and sericin stimulated the phosphorylation of ERK 1/2 and JNK 1/2 kinases. All these experiments were done in the presence of specific inhibitors for some of the cell signalling pathways referred above. The obtained results revealed that MEK, JNK and PI3K pathways are involved in fibroin and sericin stimulated cells migration. Inhibition of these three kinases prevented c-Jun upregulation and phosphorylation by fibroin or sericin. Fibroin and sericin were tested in the human keratinocyte cell line, HaCaT, with similar results. Altogether, our results showed that fibroin and sericin initiate cell migration by activating the MEK, JNK and PI3K signalling pathways ending in c-Jun activation.

Convenient synthesis of [2-14C]-methylglyoxal bis(guanylhydrazone), [14C]-mitoguazone

International Nuclear Information System (INIS)

Burgos, A.; Ellames, G.J.

1995-01-01

[2- 14 C]-Methylglyoxal bis(guanylhydrazone) dihydrochloride, [ 14 C]-mitoguazone has been prepared in three steps from potassium[1- 14 C]-acetate in an overall radiochemical yield of 16%. The key steps in this procedure are the formation of the sodium salt of[acetone-2- 14 C]-methylsulfinylacetone, and Pummerer rearrangement to the [ 14 C] labelled hermithioacetal, which is trapped with two equivalents of aminoguanidine to afford the desired [ 14 C]-mitoguazone. (Author)

Powdery mildew fungal effector candidates share N-terminal Y/F/WxC-motif

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Emmersen Jeppe

2010-05-01

Full Text Available Abstract Background Powdery mildew and rust fungi are widespread, serious pathogens that depend on developing haustoria in the living plant cells. Haustoria are separated from the host cytoplasm by a plant cell-derived extrahaustorial membrane. They secrete effector proteins, some of which are subsequently transferred across this membrane to the plant cell to suppress defense. Results In a cDNA library from barley epidermis containing powdery mildew haustoria, two-thirds of the sequenced ESTs were fungal and represented ~3,000 genes. Many of the most highly expressed genes encoded small proteins with N-terminal signal peptides. While these proteins are novel and poorly related, they do share a three-amino acid motif, which we named "Y/F/WxC", in the N-terminal of the mature proteins. The first amino acid of this motif is aromatic: tyrosine, phenylalanine or tryptophan, and the last is always cysteine. In total, we identified 107 such proteins, for which the ESTs represent 19% of the fungal clones in our library, suggesting fundamental roles in haustoria function. While overall sequence similarity between the powdery mildew Y/F/WxC-proteins is low, they do have a highly similar exon-intron structure, suggesting they have a common origin. Interestingly, searches of public fungal genome and EST databases revealed that haustoria-producing rust fungi also encode large numbers of novel, short proteins with signal peptides and the Y/F/WxC-motif. No significant numbers of such proteins were identified from genome and EST sequences from either fungi which do not produce haustoria or from haustoria-producing Oomycetes. Conclusion In total, we identified 107, 178 and 57 such Y/F/WxC-proteins from the barley powdery mildew, the wheat stem rust and the wheat leaf rust fungi, respectively. All together, our findings suggest the Y/F/WxC-proteins to be a new class of effectors from haustoria-producing pathogenic fungi.

Circulating forms of immunoreactive parathyroid hormone-related protein for identifying patients with humoral hypercalcemia of malignancy. A comparative study with C-terminal (109-141)- and N-terminal (1-86)-region-specific PTHrP radioassay

International Nuclear Information System (INIS)

Suehiro, Mitsuko; Murakami, Minoru; Fukuchi, Minoru

1994-01-01

We evaluated the circulating forms of immunoreactive parathyroid hormone-related protein(PTHrP) in 115 healthy subjects and 122 patients with malignant diseases by using radioassay systems (RAS) specific for the C-terminal (109-141) fragment of PTHrP (C-RAS) and for the N-terminal(1-86) (N-RAS). PTHrP levels in healthy controls ranged from 1.5 to 38.2 (mean: 24.5) pmol/L with the C-RAS and from 0.9 to 2.5 (mean: 1.7) pmol/L with the N-RAS. The ratio of circulating N-terminal fragment (N) to C-terminal fragment (C) of PTHrP was calculated to be about 1 : 14.4 in the healthy subjects. Of the 122 patients with malignant diseases, 40 (32.8%) had circulating PTHrP levels undetectable with the N-RAS, but only 11 (9.0%) patients had levels undetectable with the C-RAS. Of the former 122 patients, 41 (33.6%) had high PTHrP as determined with the C-RAS, and 10 (8.2%) had high PTHrP as determined with the N-RAS. The former of these included only 8 (19.5%) humoral hypercalcemia malignancy(HHM) patients, while the latter included 8 (80.0%) HHM patients. The circulating N to C ratio was about 1 : 70.7 in the HHM patients. The N and C obtained with the different RASs showed a close correlation (r=0.86). The values also showed a close correlation with serum Ca; r=0.75 for C-RAS and r=0.81 for N-RAS. In addition, the correlation between the PTHrP reading obtained with the different RASs and serum Cr were: r=0.42 with C-RAS and r=0.26 with N-RAS. The circulating form of immunoreactive PTHrP fragments is therefore comprised mainly of PTHrP (109-141). In contrast, circulating concentrations of the PTHrP (1-86) fragment are very low, but detection of the PTHrP (1-86) fragment with the N-RAS is a more useful indicator of HHM with fewer false positive results and is less likely to be influenced by renal function than the detection of the PHPrP (109-141) fragment with C-RAS. (author)

Replacement of the C-terminal tetrapeptide ( 314 PAPV 317 to 314 ...

Indian Academy of Sciences (India)

Home; Journals; Journal of Biosciences; Volume 35; Issue 4. Replacement of the C-terminal tetrapeptide (314PAPV317 to 314SSSM317) in interferon regulatory factor-2 alters its N-terminal DNA-binding activity. Krishna Prakash Pramod C Rath. Articles Volume 35 Issue 4 December 2010 pp 547-556 ...

Radiogaschromatographic analysis of volatile products of the photolysis of the system bis-(tributyltin)-oxide-(butyl-l-14C)/cellulose

International Nuclear Information System (INIS)

Kloetzer, D.; Goerner, H.; Heise, K.H.

1979-01-01

Apparatus and method for separation and identification of the products of photochemical decomposition in the system bis(tributyltin)-oxide-(butyl-1- 14 C)/cellulose are described. Ultraviolet radiation causes the formation of n-butane- 14 C and n-octane- 14 C, i.e. 14 C-labelled butyl radicals splitting off from the tin organic compound are stabilized by reactions with H atoms from the photodecomposition of cellulose or by dimerization. (author)

Unusual C-C bond cleavage in the formation of amine-bis(phenoxy) group 4 benzyl complexes: Mechanism of formation and application to stereospecific polymerization

KAUST Repository

Gowda, Ravikumar R.; Caporaso, Lucia; Cavallo, Luigi; Chen, Eugene You Xian

2014-01-01

Group 4 tetrabenzyl compounds MBn4 (M = Zr, Ti), upon protonolysis with an equimolar amount of the tetradentate amine-tris(phenol) ligand N[(2,4-tBu2C6H2(CH 2)OH]3 in toluene from -30 to 25 °C, unexpectedly lead to amine-bis(phenoxy) dibenzyl

Intracerebral infection of Cebus apella with the XJ-Clone 3 strain of Junín virus.

Science.gov (United States)

Carballal, G; Oubiña, J R; Molinas, F C; Nagle, C; de la Vega, M T; Videla, C; Elsner, B

1987-03-01

To assess the usefulness of the South American primate Cebus apella as a model for neurovirulence of Junín virus, eight monkeys were inoculated with 10(5) LD50 of the attenuated XJ-Clone 3 Junín virus strain by the intrathalamic route. After the second week, weight loss and polyadenopathies were observed in most animals, one-half of which had a transient leukothrombocytopenia. Moderate clinical central nervous system (CNS) involvement was present in four of eight monkeys, while the rest had only mild neurologic signs. All recovered except one, which developed a deep coma and was killed in a pre-mortem stage at 18 days post-infection (pi). Junín virus was isolated from the throat from five, from the blood from three, and from the brain from two monkeys. In the most severely ill animal, virus titers higher than viremia were detected in both inoculated and contralateral brain hemispheres, as well as in lung, lymph node, and small intestine. Junín antigens and "in vivo" bound immunoglobulins were detected by immunofluorescence (IF) in the brain of four animals at 18, 21, 40, and 155 days pi. Moderate lymphocytic parenchymal and meningeal infiltration were observed in the brain of four animals, and gliosis was also present in the most affected monkey. Although the clinical response to infection was not uniform, all infected monkeys developed high IF antibodies. Cebus apella cannot be used as a highly sensitive model for Argentine hemorrhagic fever (AHF). However, the results obtained show that the XJ-Clone 3 strain can replicate in the primate CNS and to induce lesions and immunoglobulin deposition. In addition, viral persistence is suggested by the late detection of viral antigens in brain at 40 and 155 days pi.

Structures of the Gasdermin D C-Terminal Domains Reveal Mechanisms of Autoinhibition.

Science.gov (United States)

Liu, Zhonghua; Wang, Chuanping; Rathkey, Joseph K; Yang, Jie; Dubyak, George R; Abbott, Derek W; Xiao, Tsan Sam

2018-05-01

Pyroptosis is an inflammatory form of programmed cell death that plays important roles in immune protection against infections and in inflammatory disorders. Gasdermin D (GSDMD) is an executor of pyroptosis upon cleavage by caspases-1/4/5/11 following canonical and noncanonical inflammasome activation. GSDMD N-terminal domain assembles membrane pores to induce cytolysis, whereas its C-terminal domain inhibits cell death through intramolecular association with the N domain. The molecular mechanisms of autoinhibition for GSDMD are poorly characterized. Here we report the crystal structures of the human and murine GSDMD C-terminal domains, which differ from those of the full-length murine GSDMA3 and the human GSDMB C-terminal domain. Mutations of GSDMD C-domain residues predicted to locate at its interface with the N-domain enhanced pyroptosis. Our results suggest that GSDMDs may employ a distinct mode of intramolecular domain interaction and autoinhibition, which may be relevant to its unique role in pyroptosis downstream of inflammasome activation. Copyright © 2018 Elsevier Ltd. All rights reserved.

40 CFR 721.10143 - Amines, bis (C11-14-branched and linear alkyl).

Science.gov (United States)

2010-07-01

... linear alkyl). 721.10143 Section 721.10143 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10143 Amines, bis (C11-14-branched and linear alkyl). (a) Chemical..., bis (C11-14-branched and linear alkyl) (PMN P-06-733; CAS No. 900169-60-0) is subject to reporting...

Crystal structure of [butane-2,3-dione bis(4-methylthiosemicarbazonato-κ4S,N1,N1′,S′](pyridine-κNzinc(II

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Oliver C. Brown

2015-11-01

Full Text Available In the structure of the title complex, [Zn(C8H14N6S2(C5H5N], the ZnII ion has a pseudo-square-pyramidal coordination environment and is displaced by 0.490 Å from the plane of best fit defined by the bis(thiosemicarbazonate N2S2 donor atoms. Chains sustained by intermolecular N—H...N and N—H...S hydrogen-bonding interactions extend parallel to [10-1].

Nonacarbonyl-1κ3C,2κ3C,3κ3C-μ-bis(diphenylarsinomethane-1:2κ2As:As'-[tris(2-chloroethyl phosphite-3κP]-triangulo-triruthenium(0

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Omar bin Shawkataly

2010-08-01

Full Text Available In the title triangulo-triruthenium(0 compound, [Ru3(C25H22As2(C6H12Cl3O3P(CO9], the bis(diphenylarsinomethane ligand bridges an Ru—Ru bond and the monodentate phosphine ligand bonds to the third Ru atom. Both the arsine and phosphine ligands are equatorial with respect to the Ru3 triangle. In addition, each Ru atom carries one equatorial and two axial terminal carbonyl ligands. In the crystal packing, the molecules are linked by intermolecular C—H...O hydrogen bonds into a three-dimensional framework. Weak intermolecular C—H...π interactions further stabilize the crystal structure.

The intriguing role of fibroblasts and c-Jun in the chemopreventive and therapeutic effect of finasteride on xenograft models of prostate cancer

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Yi-Nong Niu

2016-01-01

Full Text Available In a large clinical trial, finasteride reduced the rate of low-grade prostate cancer (PCa while increasing the incidence of high-grade cancer. Whether finasteride promotes the development of high-grade tumors remains controversial. We demonstrated the role of fibroblasts and c-Jun in chemopreventive and therapeutic effect of finasteride on xenograft models of PCa. LNCaP (PC3 cells or recombinants of cancer cells and fibroblasts were implanted in male athymic nude mice treated with finasteride. Tumor growth, cell proliferation, apoptosis, p-Akt, and p-ERK1/2 were evaluated. In LNCaP (PC3 mono-grafted models, finasteride did not change the tumor growth. In recombinant-grafted models, fibroblasts and c-Jun promoted tumor growth; finasteride induced proliferation of LNCaP cells and repressed PC3 cell apoptosis. When c-Jun was knocked out, fibroblasts and/or finasteride did not promote the tumor growth. Finasteride inhibited p-Akt and p-ERK1/2 in mono-culture cancer cells while stimulating the same signaling molecules in the presence of fibroblasts. Reduced p-Akt and p-ERK1/2 were noted in the presence of c-Jun−/− fibroblasts. Fibroblasts and c-Jun promote PCa growth; finasteride further stimulates tumor growth with promoted proliferation, repressed apoptosis, and up-regulated pro-proliferative molecular pathway in the presence of fibroblasts and c-Jun. Stromal-epithelial interactions play critical roles in finasteride′s therapeutic effects on PCa. Our findings have preliminary implications in using finasteride as a chemopreventive or therapeutic agent for PCa patients.

The EspF N-Terminal of Enterohemorrhagic Escherichia coli O157:H7 EDL933w Imparts Stronger Toxicity Effects on HT-29 Cells than the C-Terminal

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Xiangyu Wang

2017-09-01

Full Text Available Enterohemorrhagic Escherichia coli (EHEC O157:H7 EspF is an important multifunctional protein that destroys the tight junctions of intestinal epithelial cells and promotes host cell apoptosis. However, its molecular mechanism remains elusive. We knocked out the espF sequence (747 bp, ΔespF, N-terminal sequence (219 bp, ΔespFN, and C-terminal sequence (528 bp, ΔespFC separately using the pKD46-mediated λ Red homologous recombination system. Then, we built the corresponding complementation strains, namely, ΔespF/pespF, ΔespFN/pespFN, and ΔespFC/pespFC by overlap PCR, which were used in infecting HT-29 cells and BALB/C mice. The level of reactive oxygen species, cell apoptosis, mitochondrial trans-membrane potential, inflammatory factors, transepithelial electrical resistance (TER, and animal mortality were evaluated by DCFH-DA, double staining of Annexin V-FITC/PI, JC-1 staining, ELISA kit, and a mouse assay. The wild-type (WT, ΔespF, ΔespF/pespF, ΔespFC, ΔespFC/pespFC, ΔespFN, and ΔespFN/pespFN groups exhibited apoptotic rates of 68.3, 27.9, 64.9, 65.7, 73.4, 41.3, and 35.3% respectively, and mean TNF-α expression levels of 428 pg/mL, 342, 466, 446, 381, 383, and 374 pg/mL, respectively. In addition, the apoptotic rates and TNF-α levels of the WT, ΔespF/pespF, and ΔespFC were significantly higher than that of ΔespF, ΔespFN, ΔespFC/pespFC, and ΔespFN/pespFN group (p < 0.05. The N-terminal of EspF resulted in an increase in the number of apoptotic cells, TNF-α secretion, ROS generation, mitochondria apoptosis, and pathogenicity in BalB/c mice. In conclusion, the N-terminal domain of the Enterohemorrhagic E. coli O157:H7 EspF more strongly promotes apoptosis and inflammation than the C-terminal domain.

INAA analysis for Jun porcelaim and modern Chinese Jun porcelain

International Nuclear Information System (INIS)

Jia Xiuqin; Dong Jinquan; Han Song; Tang Yunhui

2004-01-01

A total of 28 old Jun porcelain, seven modern Chinese Jun porcelain and two Jingdezhen porcelain samples are analyzed with INAA method. The systematic geochemical study for these 37 samples on their REE and trace elements shows that these three types of china were made with relatively stable and similar material, although they leaptover 600 years in different colors and from different kilns. However, the REE patterns of modern Chinese Jun porcelain are a little bit different from that of old Jun porcelain, and clear different from the old glaze of Jindezheng. (authors)

Crystal structure of [2-({4-[2,6-bis(pyridin-2-ylpyridin-4-yl]phenyl}(methylaminoethanol-κ3N,N′,N′′]bis(thiocyanato-κNzinc N,N-dimethylformamide monosolvate

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Shi-Chao Wang

2014-10-01

Full Text Available In the title compound, [Zn(NCS2(C24H22N4O]·C3H7NO, the ZnII cation is N,N′,N′′-chelated by one 2-({4-[2,6-bis(pyridin-2-ylpyridin-4-yl]phenyl}(methylaminoethanol ligand and coordinated by two thiocyanate anions in a distorted N5 trigonal–bipyramidal geometry. In the molecule, the three pyridine rings are approximately coplanar [maximum deviation = 0.026 (5 Å], and the mean plane of the three pyridine rings is twisted to the benzene ring with a small dihedral angle of 5.9 (2°. In the crystal, complex molecules are linked by weak C—H...O hydrogen bonds into supramolecular chains propagated along [110]; π–π stacking is observed between adjacent chains [centroid–centroid distance = 3.678 (4 Å]. The dimethylformamide solvent molecules are linked with the complex chains via weak C—H...O hydrogen bonds.

Especies de miridae (hemiptera) registradas en algunos cultivos tropicales en Chanchamayo y Satipo. Junín - Perú

OpenAIRE

Arellano, Germán; Vergara, Clorinda

2016-01-01

El presente estudio tuvo como objetivo identificar las especies de insectos Miridae(Hemiptera) presentes en seis cultivos tropicales en la selva del Departamento de Junín, Perú. Se considera como base las recolecciones realizadas entre los años 1983 a 1987. El muestreo se basó en colectas periódicas semanales de insectos en las plantaciones de cafeto (Coffea arabica L.), papayo (Carica papaya L.), piña (Ananas comosus var. comosus (L.) Merr., Coppens & Leal), palto (Persea americana Mill), cí...

Diaqua[N,N′-bis(2-pyridylmethylenepropane-1,3-diamine]manganese(II dibromide–aquabromido[N,N′-bis(2-pyridylmethylenepropane-1,3-diamine]manganese(II bromide–dibromido[N,N′-bis(2-pyridylmethylenepropane-1,3-diamine]manganese(II (1/2/1

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In-Chul Hwang

2009-01-01

Full Text Available There are three different MnII complexes in the asymmetric unit of the title compound, [Mn(C15H16N4(H2O2]Br2·2{[MnBr(C15H16N4(H2O]Br}·[MnBr2(C15H16N4]. In the neutral complex, the Mn2+ ion is six-coordinated in a distorted octahedral environment by four N atoms of the tetradentate ligand N,N′-bis(2-pyridylmethylenepropane-1,3-diamine (bppd and two bromide ligands. In the two cationic complexes, the Mn2+ ions are also six-coordinated in similar environments, but one Mn ion is coordinated by four N atoms of bppd, one Br atom and one O atom of a coordinating water molecule, whereas the other Mn ion is coordinated by four N atoms of bppd and two O atoms of water ligands. The complexes with two coordinated Br atoms or two H2O ligands are disposed about a twofold axis through Mn and C atoms with the special positions ({script{1over 2}}, y, 0 and (0, y, {script{1over 2}}, respectively. The compound displays intermolecular O—H...Br hydrogen bonding. There are intermolecular π–π interactions between adjacent pyridine rings, with centroid–centroid distances of 3.822 and 3.833 Å, and a C—H...O interaction is also present.

Synthesis and biodistribution of lipophilic and monocationic gallium radiopharmaceuticals derived from N,N'-bis(3-aminopropyl)-N,N'-dimethylethylenediamine: potential agents for PET myocardial imaging with 68Ga

International Nuclear Information System (INIS)

Hsiao, Y.-M.; Mathias, Carla J.; Wey, S.-P.; Fanwick, Phillip E.; Green, Mark A.

2009-01-01

Introduction: In locations that lack nearby cyclotron facilities for radionuclide production, generator-based 68 Ga radiopharmaceuticals might have clinical utility for positron emission tomography (PET) studies of myocardial perfusion and other physiological processes. Methods: The lipophilic and monocationic 67 Ga-labeled gallium chelates of five novel hexadentate bis(salicylaldimine) ligands the bis(salicylaldimine), bis(3-methoxysalicylaldimine), bis(4-methoxysalicylaldimine), bis(6-meth,oxysalicylaldimine), and bis(4,6-dimethoxysalicylaldimine) of N,N'-bis(3-aminopropyl)-N,N'-dimethylethylenediamine (BAPDMEN), were prepared. The structure of the unlabeled [Ga(4-MeOsal) 2 BAPDMEN] + PF 6 - salt was determined by X-ray crystallography, and the biodistribution of each of the 67 Ga-labeled gallium chelates was determined in rats following intravenous administration and compared with the biodistribution of [ 86 Rb]rubidium chloride. Results: The [Ga(4-MeOsal) 2 BAPDMEN] + PF 6 - complex exhibited the expected pseudo-octahedral N 4 O 2 2- coordination sphere about the Ga 3+ center with a trans disposition of the phenolate oxygen atoms. All five 67 Ga radiopharmaceuticals were found to afford the desired myocardial retention of the radiogallium. The [ 67/68 Ga][Ga(3-MeOsal) 2 BAPDMEN] 1+ radiopharmaceutical appears to have the best properties for myocardial imaging, exhibiting 2% of the injected dose in the heart 1 min and 2 h postinjection and very high heart/nontarget ratios (heart/blood ratios of 7.6±1.0 and 54±10 at 1 and 120 min, respectively; heart/liver ratios of 1.8±0.4 and 39±3 at 1 and 120 min, respectively). Conclusions: Most of these new agents, particularly [ 67/68 Ga][Ga(3-MeOsal) 2 BAPDMEN] 1+ , would appear superior to previously reported bis(salicylaldimine) ligands of N,N'-bis(3-aminopropyl)ethylenediamine as candidates for PET imaging of the heart with 68 Ga

C-terminal peptide extension via gas-phase ion/ion reactions

Science.gov (United States)

Peng, Zhou; McLuckey, Scott A.

2015-01-01

The formation of peptide bonds is of great importance from both a biological standpoint and in routine organic synthesis. Recent work from our group demonstrated the synthesis of peptides in the gas-phase via ion/ion reactions with sulfo-NHS reagents, which resulted in conjugation of individual amino acids or small peptides to the N-terminus of an existing ‘anchor’ peptide. Here, we demonstrate a complementary approach resulting in the C-terminal extension of peptides. Individual amino acids or short peptides can be prepared as reagents by incorporating gas phase-labile protecting groups to the reactive C-terminus and then converting the N-terminal amino groups to the active ketenimine reagent. Gas-phase ion/ion reactions between the anionic reagents and doubly protonated “anchor” peptide cations results in extension of the “anchor” peptide with new amide bond formation at the C-terminus. We have demonstrated that ion/ion reactions can be used as a fast, controlled, and efficient means for C-terminal peptide extension in the gas phase. PMID:26640400

Triptolide, a diterpenoid triepoxide, induces antitumor proliferation via activation of c-Jun NH2-terminal kinase 1 by decreasing phosphatidylinositol 3-kinase activity in human tumor cells

International Nuclear Information System (INIS)

Miyata, Yoshiki; Sato, Takashi; Ito, Akira

2005-01-01

Triptolide, a diterpenoid triepoxide extracted from the Chinese herb Tripterygium wilfordii Hook f., exerts antitumorigenic actions against several tumor cells, but the intracellular target signal molecule(s) for this antitumorigenesis activity of triptolide remains to be identified. In the present study, we demonstrated that triptolide, in a dose-dependent manner, inhibited the proliferation of human fibrosarcoma HT-1080, human squamous carcinoma SAS, and human uterine cervical carcinoma SKG-II cells. In addition, triptolide was found to decrease phosphatidylinositol 3-kinase (PI3K) activity. A PI3K inhibitor, LY-294002, mimicked the triptolide-induced antiproliferative activity in HT-1080, SAS, and SKG-II cells. There was no change in the activity of Akt or protein kinase C (PKC), both of which are downstream effectors in the PI3K pathway. Furthermore, the phosphorylation of Ras, Raf, and mitogen-activated protein/extracellular signal-regulated kinase 1/2 was not modified in HT-1080 cells treated with triptolide. However, the phosphorylation of c-Jun NH 2 -terminal kinase 1 (JNK1) was found to increase in both triptolide- and LY-294002-treated cells. Furthermore, the triptolide-induced inhibition of HT-1080 cell proliferation was not observed by JNK1 siRNA-treatment. These results provide novel evidence that PI3K is a crucial target molecule in the antitumorigenic action of triptolide. They further suggest a possible triptolide-induced inhibitory signal for tumor cell proliferation that is initiated by the decrease in PI3K activity, which in turn leads to the augmentation of JNK1 phosphorylation via the Akt and/or PKC-independent pathway(s). Moreover, it is likely that the activation of JNK1 is required for the triptolide-induced inhibition of tumor proliferation

Characterization of cDNA for human tripeptidyl peptidase II: The N-terminal part of the enzyme is similar to subtilisin

International Nuclear Information System (INIS)

Tomkinson, B.; Jonsson, A-K

1991-01-01

Tripeptidyl peptidase II is a high molecular weight serine exopeptidase, which has been purified from rat liver and human erythrocytes. Four clones, representing 4453 bp, or 90% of the mRNA of the human enzyme, have been isolated from two different cDNA libraries. One clone, designated A2, was obtained after screening a human B-lymphocyte cDNA library with a degenerated oligonucleotide mixture. The B-lymphocyte cDNA library, obtained from human fibroblasts, were rescreened with a 147 bp fragment from the 5' part of the A2 clone, whereby three different overlapping cDNA clones could be isolated. The deduced amino acid sequence, 1196 amino acid residues, corresponding to the longest open rading frame of the assembled nucleotide sequence, was compared to sequences of current databases. This revealed a 56% similarity between the bacterial enzyme subtilisin and the N-terminal part of tripeptidyl peptidase II. The enzyme was found to be represented by two different mRNAs of 4.2 and 5.0 kilobases, respectively, which probably result from the utilziation of two different polyadenylation sites. Futhermore, cDNA corresponding to both the N-terminal and C-terminal part of tripeptidyl peptidase II hybridized with genomic DNA from mouse, horse, calf, and hen, even under fairly high stringency conditions, indicating that tripeptidyl peptidase II is highly conserved

Simultaneous regioselective synthesis of trifluoromethyl-containing 1,7-phenanthrolines and quinolines from cyclocondensation reaction of N,N'-bis(oxotrifluoroalkenyl)-1,3-phenylenediamines

Energy Technology Data Exchange (ETDEWEB)

Bonacorso, Helio G.; Andrighetto, Rosalia; Krueger, Nicolas; Martins, Marcos A.P.; Zanatta, Nilo [Universidade Federal de Santa Maria (NUQUIMHE/UFSM), RS (Brazil). Dept. de Quimica. Nucleo de Quimica de Heterociclos

2011-08-15

This paper reports interesting results of the conventional synthesis of a new series of 2,10-dialkyl(aryl)-4,8-bis(trifluoromethyl)-1,7-phenanthrolines, in 22-40% yields, from cyclization reactions of N,N'-bis(oxotrifluoroalkenyl)-1,3-phenylenediamines [1,3-C{sub 6}H{sub 4}-(NHCR=CHC(O)CF{sub 3}){sub 2}] in a strongly acidic medium and absence of solvent. The synthetic route also allowed the isolation of a new series of 2-alkyl(aryl/heteroaryl)-4-trifluoromethyl-7-aminoquinolines, in 20-73% yields, simultaneously. The enaminone precursors were obtained from the reaction of 4-alkoxy-1,1,1-trifluoroalk-3-en-2-ones [CF{sub 3}C(O)CH=C(R)OR1, where R = H, Me, Ph, 4-MePh, 4-OMePh, 4-ClPh, 4-FPh, 4-BrPh, 4-NO{sub 2}Ph, 2-furyl and R1 = Me, Et] with 1,3-phenylenediamine under mild conditions, in 47-91% yields. (author)

Detection of prosecretory mitogen lacritin in nonprimate tears primarily as a C-terminal-like fragment.

Science.gov (United States)

Laurie, Diane E; Splan, Rebecca K; Green, Kari; Still, Katherine M; McKown, Robert L; Laurie, Gordon W

2012-09-12

Lacritin is a human tear glycoprotein that promotes basal tear protein secretion in cultured rat lacrimal acinar cells and proliferation of subconfluent human corneal epithelial cells. When topically added to rabbit eyes, lacritin promotes basal tearing. Despite these activities on several species, lacritin's presence in nonprimate tears or other tissues has not been explored. Here we probed for lacritin in normal horse tears. Sequences were collected from the Ensembl genomic alignment of human LACRT gene with high-quality draft horse genome (EquCab2.0) and analyzed. Normal horse tears were collected and assayed by Western blotting, ELISA, and mass spectrometry. Newly generated rabbit antibodies, respectively, against N- and C-terminal regions of human lacritin were employed. Identity was 75% and 45%, respectively, at nucleotide and protein levels. Structural features were conserved, including a C-terminal amphipathic α-helix. Anti-C-terminal antibodies strongly detected a ∼13 kDa band in horse tears that was validated by mass spectrometry. In human tears, the same antibody detected uncleaved lacritin (∼24 kDa) strongly and C-terminal fragments of ∼13 and ∼11 kDa weakly. Anti-N-terminal antibodies were slightly reactive with a ∼24 kDa horse antigen and showed no reaction with the anti-C-terminal-reactive ∼13 kDa species. Similar respective levels of horse C-terminal versus N-terminal immunoreactivity were apparent by ELISA. Lacritin is present in horse tears, largely as a C-terminal fragment homologous to the mitogenic and bactericidal region in human lacritin, suggesting potential benefit in corneal wound repair.

Updating the profile of C-terminal MECP2 deletions in Rett syndrome

Science.gov (United States)

Bebbington, A; Percy, A; Christodoulou, J; Ravine, D; Ho, G; Jacoby, P; Anderson, A; Pineda, M; Ben Zeev, B; Bahi-Buisson, N; Smeets, E; Leonard, H

2014-01-01

Objectives This study aimed to compare the phenotype of Rett syndrome cases with C-terminal deletions to that of cases with different MECP2 mutations and to examine the phenotypic variation within C-terminal deletions. Methods Cases were selected from InterRett, an international database and from the population-based Australian Rett Syndrome Database. Cases (n=832) were included if they had a pathogenic MECP2 mutation in which the nature of the amino acid change was known. Three severity scale systems were used, and individual aspects of the phenotype were also compared. Results Lower severity was associated with C-terminal deletions (n=79) compared to all other MECP2 mutations (e.g. Pineda scale C-terminals mean 15.0 (95% CI 14.0–16.0) vs 16.2 (15.9–16.5). Cases with C-terminal deletions were more likely to have a normal head circumference (odds ratio 3.22, 95% CI 1.53 – 6.79) and weight (odds ratio 2.97, 95% CI 1.25–5.76). Onset of stereotypies tended to be later (median age 2.5 years vs 2 years, pmiddle of the range. In terms of individual aspects of phenotype growth and ability to ambulate appear to be particular strengths. By pooling data internationally this study has achieved the case numbers to provide a phenotypic profile of C-terminal deletions in Rett syndrome. PMID:19914908

Synthesis, characterization and antibacterial activity of some novel symmetrical n/sup 3/, n/sup 3/-bis(disubstituted)isophthalyl-bis(thioureas) and their Cu(II) and Ni(II) complexes

International Nuclear Information System (INIS)

Jamil, M.; Zubair, M.; Rasool, N.; Bukhari, I.H.; Farid, M.A.; Altaf, A.A.

2013-01-01

A series of some novel N/sup 3/,N/sup 3/-bis(disubstituted) isophthalyl-bis(thioureas) compounds with general formula (C/sub 6/H/sub 4/(CONHCSNHR)/sub 2/), where R = 4-C/sub 6/H/sub 4/COOH(L/sub 1/), 3-NO/sub 2/C/sub 6/H/sub 4/(L/sub 2/), 2-NO/sub 2/C/sub 6/H/sub 4/(L/sub 3/), 4-CH/sub 3/C/sub 6/H/sub 4/(L/sub 4/), 2-CH/sub 3/C/sub 6/H/sub 4/(L/sub 5/), 3-CH/sub 3/C/sub 6/H/sub 4/(L/sub 6/) and their Cu(II) and Ni(II) complexes have been synthesized. (L/sub 1/-L/sub 6/) have been prepared in good to excellent yields by reaction of isophthaloyl isothiocyanate with primary amines using dry acetone as solvent. The stoichiometric reaction between the metal (II) ion and synthesized ligands in molar ratio of M : L (1 : 1) resulted in the formation of the metal complexes of type (ML)2 (where M = Cu(II) and Ni(II). These compounds (L/sub 1/-L/sub 6/) and their metal (II) complexes have been characterized by elemental analyses, Infrared spectroscopy, /sup 1/H-NMR spectroscopy, magnetic moments, and electronic spectral measurements. These compounds (L/sub 1/-L/sub 6/) and their metal (II) complexes were also screened for their antibacterial activity against bacterial species, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Shigella sonnei, Salmonella typhi and Pseudomonas aeroginosa. Some compounds showed potential activity against a number of bacterial strains. The results of these studies also show the metal (II) complexes to be having stronger antibacterial activityl against one or more species as compared to the uncomplexed ligands. It was concluded that these compounds may be the potential source of active antibacterial agents. (author)

Unusual C-C bond cleavage in the formation of amine-bis(phenoxy) group 4 benzyl complexes: Mechanism of formation and application to stereospecific polymerization

KAUST Repository

Gowda, Ravikumar R.

2014-08-11

Group 4 tetrabenzyl compounds MBn4 (M = Zr, Ti), upon protonolysis with an equimolar amount of the tetradentate amine-tris(phenol) ligand N[(2,4-tBu2C6H2(CH 2)OH]3 in toluene from -30 to 25 °C, unexpectedly lead to amine-bis(phenoxy) dibenzyl complexes, BnCH2N[(2,4- tBu2C6H2(CH2)O] 2MBn2 (M = Zr (1), Ti (2)) in 80% (1) and 75% (2) yields. This reaction involves an apparent cleavage of the >NCH2-ArOH bond (loss of the phenol in the ligand) and formation of the >NCH 2-CH2Bn bond (gain of the benzyl group in the ligand). Structural characterization of 1 by X-ray diffraction analysis confirms that the complex formed is a bis(benzyl) complex of Zr coordinated by a newly derived tridentate amine-bis(phenoxy) ligand arranged in a mer configuration in the solid state. The abstractive activation of 1 and 2 with B(C6F 5)3·THF in CD2Cl2 at room temperature generates the corresponding benzyl cations {BnCH2N[(2,4- tBu2C6H2(CH2)O] 2MBn(THF)}+[BnB(C6F5) 3]- (M = Zr (3), Ti, (4)). These cationic complexes, along with their analogues derived from (imino)phenoxy tri- and dibenzyl complexes, [(2,6-iPr2C6H3)N=C(3,5- tBu2C6H2)O]ZrBn3 (5) and [2,4-Br2C6H2(O)(6-CH2(NC 5H9))CH2N=CH(2-adamantyl-4-MeC 6H2O)]ZrBn2 (6), have been found to effectively polymerize the biomass-derived renewable β-methyl-α-methylene- γ-butyrolactone (βMMBL) at room temperature into the highly stereoregular polymer PβMMBL with an isotacticity up to 99% mm. A combined experimental and DFT study has yielded a mechanistic pathway for the observed unusual C-C bond cleavage in the present protonolysis reaction between ZrBn4 and N[(2,4-tBu2C 6H2(CH2)OH]3 for the formation of complex 1, which involves the benzyl radical and the Zr(III) species, resulting from thermal and photochemical decomposition of ZrBn4, followed by a series of reaction sequences consisting of protonolysis, tautomerization, H-transfer, oxidation, elimination, and radical coupling. © 2014 American Chemical Society.

Discovery of novel alkylated (bis)urea and (bis)thiourea polyamine analogues with potent antimalarial activities.

Science.gov (United States)

Verlinden, Bianca K; Niemand, Jandeli; Snyman, Janette; Sharma, Shiv K; Beattie, Ross J; Woster, Patrick M; Birkholtz, Lyn-Marie

2011-10-13

A series of alkylated (bis)urea and (bis)thiourea polyamine analogues were synthesized and screened for antimalarial activity against chloroquine-sensitive and -resistant strains of Plasmodium falciparum in vitro. All analogues showed growth inhibitory activity against P. falciparum at less than 3 μM, with the majority having effective IC(50) values in the 100-650 nM range. Analogues arrested parasitic growth within 24 h of exposure due to a block in nuclear division and therefore asexual development. Moreover, this effect appears to be cytotoxic and highly selective to malaria parasites (>7000-fold lower IC(50) against P. falciparum) and is not reversible by the exogenous addition of polyamines. With this first report of potent antimalarial activity of polyamine analogues containing 3-7-3 or 3-6-3 carbon backbones and substituted terminal urea- or thiourea moieties, we propose that these compounds represent a structurally novel class of antimalarial agents.

Synsepalum dulcificum extracts exhibit cytotoxic activity on human colorectal cancer cells and upregulate c-fos and c-jun early apoptotic gene expression

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Jichang Seong

2018-01-01

Full Text Available Objective: To explore cytotoxicity of Synsepalum dulcificum (S. dulcificum Daniell (Sapotaceae on human colon cancer (HCT-116 and HT-29, human monocytic leukemia (THP-1 and normal (HDFn cell lines, and its effect on the expression of early apoptotic genes, c-fos and c-jun. Methods: Leaf, stem and berry of S. dulcificum were separately extracted by using 2 solvents, 10% ethanol (EtOH and 80% methanol (MeOH. PrestoBlue® cell viability assay and qRT-PCR assay were conducted to examine the above objectives respectively. Results: Stem MeOH, stem EtOH, and berry EtOH extracts of S. dulcificum were cytotoxic to HCT-116 and HT-29 human colon cancer cells. For HCT-116, IC50 values of these 3 extracts were not significantly different (P>0.05 from that of the positive control bleomycin (IC50 of 33.57 μg/mL, while for HT-29, IC50 values of these 3 extracts were significantly lower (P<0.05 than that of bleomycin (IC50 of 25.24 μg/mL. None of the extracts were cytotoxic to the THP-1 monocytic leukemia cells and HDFn normal human dermal fibroblasts. For both HCT-116 and HT-29, these extracts significantly up-regulated (P<0.05 the expression of c-fos and c-jun compared to the untreated negative control. Conclusions: The results of this study suggest that cytotoxicity of stem MeOH, stem EtOH, and berry EtOH extracts of S. dulcificum on HCT-116 and HT-29 colon cancer cells is due to the induced apoptosis which is caused by the up-regulation of the expression of early apoptotic genes, c-fos and c-jun.

Structure of poly[diaqua[μ-1,2-bis(pyridin-4-ylethane-κ2N:N′]bis(μ3-cyclobutane-1,1-dicarboxylato-κ3O,O′:O′′:O′′′dimanganese(II

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Do Nam Lee

2015-08-01

Full Text Available In the title compound, [Mn(C6H6O4(C12H12N2(H2O]n, the cyclobutane-1,1-dicarboxylate (cbdc ligands bridge three MnII ions, forming layers parallel to the ac plane. These layers are additionally connected by 1,2-bis(pyridin-4-ylethane ligands to form a three-dimensional polymeric framework. An inversion centre is located at the mid-point of the central C—C bond of the 1,2-bis(pyridin-4-ylethane ligand. The coordination geometry of the MnII ion is distorted octahedral and is built up by four carboxylate O atoms, one water O atom and a pyridyl N atom. The pyridine ligand and the coordinating water molecule are in a trans configuration. One carboxylate group of the cbdc ligand acts as a chelating ligand towards one MnII atom, whereas the second carboxylate group coordinates two different MnII atoms.

Effect of bisphosphonates on NFATc1 and correlators p-NF-κB and p-c-Jun in osteoclast differentiation

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Wei DONG

2015-11-01

Full Text Available Objective　To study the effect of alendronate (ALN on NFATc1 and correlated signaling factors p-NF-κB and p-c-Jun in osteoclast differentiation. Methods　Osteoclasts were inductively cultivated with mouse mononuclear macrophage RAW264.7, and they were divided into 2 groups: group A (control group and group B (ALN-treated group. The protein expressions of NFATc1, p-NF-κB and p-c-Jun were determined with Western blotting at the 2nd day of cultivation; the expression of NFATc1 was assessed by immunofluorescent assay on the 4th day; and the osteoclast formation was examined on the 7th day of cultivation. RAW264.7 cells were inoculated on abrasive dentine disk, and divided into 2 groups and treated as mentioned above. The resorption function of osteoclast was observed on the 9th day of inoculation. Results　TRAP positive multinuclear osteoclasts were observed, and resorption lacunaes formed in the abrasive dentine disks of the 2 groups. More TRAP positive multinuclear cells and resorption lacunaes in large size were found in group A than those in group B. Immunofluorescence assay showed the expression of NFATc1 was higher in group A than in group B. The gene expressions of NFATc1, p-NF-κB and p-c-Jun were lower in group B than in group A(P<0.01 as determined with Western blotting. Conclusion　By down-regulating the expressions of p-NF-κB and p-c-Jun, ALN may strongly inhibit the osteoclast formation and its resorption function, thus inhibiting NFATc1 expression. DOI: 10.11855/j.issn.0577-7402.2015.10.02

Microwave assisted synthesis of bis and tris(ω-bromoacetophenones): versatile precursors for novel bis(imidazo[1,2-a]pyridines), bis(imidazo[1,2-a]pyrimidines) and their tris-analogs

Science.gov (United States)

2013-01-01

Background α-Bromination of the side chain of aromatic ketones using NBS in the presence of p-toluenesulfonic acid (p-TsOH) in acetonitrile is very common. However, regioselective bromination of bis and tris(ω-bromoacetophenones) with NBS in the presence of p-TsOH in acetonitrile under microwave irradiation is quite novel. The bis- and tris(ω-bromoacetophenones) are used in synthesis of bis and tris(heterocycles). bis(heterocycles) have received a great deal of attention, because many biologically active natural and synthetic products have molecular symmetry. The use of the pressurized microwave irradiation is very advantageous to many syntheses and provide a large rate enhancement. Results Bis and tris(ω-bromoacetophenones) were obtained as single monobrominated derivatives in a shorter time than the conventional conditions. The results clearly demonstrate the better reactivity and selectivity of NBS/p-TsOH/CH3CN as a brominating mixture under microwave conditions. The reaction of bis and tris(ω-bromoacetophenone) with 2-aminopyridine and 2-aminopyrimidine proceeded smoothly in a mixture of anhydrous ethanol and DMF under reflux or using 300 W/105°C/ 20 min microwave irradiation conditions to afford the corresponding bis(imidazo[1,2-a]pyridine), bis(imidazo[1,2-a]pyrimidine) and tris(imidazo[1,2-a]pyridine) derivatives in moderate to excellent yields. The carbonyl analogue of the targeted bis(imidazopyridines) could be synthesized by the reaction of N,N-dimethyl-N'-(pyridin-2-yl)formimidamide with bis(ω-bromoacetophenone) in refluxing ethanol. The structures of the newly synthesized compounds were confirmed by their spectral data as well as their elemental analyses. Conclusion In conclusion, selective α-bromination of bis- and tris(acetophenones) has been accomplished efficiently utilizing NBS/p-TsOH/CH3CN under microwave irradiation. In addition, a facile synthesis of novel series of bis- and tris(imidazopyridine) and bis(imidazopyrimidine) derivatives

(Acetonitrile[bis(2-pyridylmethylamine]bis(perchloratocopper(II

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Ray J. Butcher

2008-01-01

Full Text Available In the title compound, [Cu(ClO42(C12H13N3(C2H3N], the CuII atom is six-coordinate in a Jahn–Teller distorted octahedral geometry, with coordination by the tridentate chelating ligand, an acetonitrile molecule, and two axial perchlorate anions. The tridentate ligand bis(2-pyridylmethylamine chelates meridionally and equatorially while an acetonitrile molecule is coordinated at the fourth equatorial site. The two perchlorate anions are disordered with site occupancy factors of 0.72/0.28. The amine H is involved in intramolecular hydrogen bonding to the perchlorate O atoms and there are extensive but weak intermolecular C—H...O interactions.

Crystal Structure of the N-terminal Domain of the Group B Streptococcus Alpha C Protein

Energy Technology Data Exchange (ETDEWEB)

Auperin,T.; Bolduc, G.; Baron, M.; Heroux, A.; Filman, D.; Madoff, L.; Hogle, J.

2005-01-01

Group B Streptococcus (GBS) is the leading cause of bacterial pneumonia, sepsis, and meningitis among neonates and an important cause of morbidity among pregnant women and immunocompromised adults. Invasive diseases due to GBS are attributed to the ability of the pathogen to translocate across human epithelial surfaces. The alpha C protein (ACP) has been identified as an invasin that plays a role in internalization and translocation of GBS across epithelial cells. The soluble N-terminal domain of ACP (NtACP) blocks the internalization of GBS. We determined the 1.86-{angstrom} resolution crystal structure of NtACP comprising residues Ser{sup 52} through Leu{sup 225} of the full-length ACP. NtACP has two domains, an N-terminal {beta}-sandwich and a C-terminal three-helix bundle. Structural and topological alignments reveal that the {beta}-sandwich shares structural elements with the type III fibronectin fold (FnIII), but includes structural elaborations that make it unique. We have identified a potential integrin-binding motif consisting of Lys-Thr-Asp{sup 146}, Arg{sup 110}, and Asp{sup 118}. A similar arrangement of charged residues has been described in other invasins. ACP shows a heparin binding activity that requires NtACP. We propose a possible heparin-binding site, including one surface of the three-helix bundle, and nearby portions of the sandwich and repeat domains. We have validated this prediction using assays of the heparin binding and cell-adhesion properties of engineered fragments of ACP. This is the first crystal structure of a member of the highly conserved Gram-positive surface alpha-like protein family, and it will enable the internalization mechanism of GBS to be dissected at the atomic level.

Crystal structure of tris(1,10-phenanthroline-κ2N,N′iron(II bis[bis(trifluoromethylsulfonylimide] monohydrate

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Kazunori Teramoto

2015-01-01

Full Text Available The crystal structure of the title complex, [Fe(C12H8N23][(CF3SO22N]2·H2O, is constructed by one octahedral [Fe(phen3]2+ (phen = 1,10-phenanthroline cation (point group symmetry 2, two Tf2N− [bis(trifluoromethylsulfonylimide] anions, and one water molecule of crystallization (point group 2. The Fe—N bond lengths are indicative of a d6 low-spin state for the FeII ion in the complex. The dihedral angle between the phen ligands in the cation is 87.64 (6°. The Tf2N− counter-anion is non-coordinating, with the –CF3 groups arranged in a trans fashion with respect to each other, leading to an anti,anti conformation of the –CF3 groups and –SO2N– moieties relative to the S—C bonds. The water molecule of crystallization connects two O atoms of the Tf2N− anions through weak hydrogen bonds. C—H...O hydrogen-bonding interactions are also observed, consolidating the packing of the molecules into a three-dimensional network structure.

The C-terminal domain of the Bloom syndrome DNA helicase is essential for genomic stability

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Noonan James P

2001-07-01

Full Text Available Abstract Background Bloom syndrome is a rare cancer-prone disorder in which the cells of affected persons have a high frequency of somatic mutation and genomic instability. Bloom syndrome cells have a distinctive high frequency of sister chromatid exchange and quadriradial formation. BLM, the protein altered in BS, is a member of the RecQ DNA helicase family, whose members share an average of 40% identity in the helicase domain and have divergent N-terminal and C-terminal flanking regions of variable lengths. The BLM DNA helicase has been shown to localize to the ND10 (nuclear domain 10 or PML (promyelocytic leukemia nuclear bodies, where it associates with TOPIIIα, and to the nucleolus. Results This report demonstrates that the N-terminal domain of BLM is responsible for localization of the protein to the nuclear bodies, while the C-terminal domain directs the protein to the nucleolus. Deletions of the N-terminal domain of BLM have little effect on sister chromatid exchange frequency and chromosome stability as compared to helicase and C-terminal mutations which can increase SCE frequency and chromosome abnormalities. Conclusion The helicase activity and the C-terminal domain of BLM are critical for maintaining genomic stability as measured by the sister chromatid exchange assay. The localization of BLM into the nucleolus by the C-terminal domain appears to be more important to genomic stability than localization in the nuclear bodies.

C-Terminal carbohydrate-binding module 9_2 fused to the N-terminus of GH11 xylanase from Aspergillus niger.

Science.gov (United States)

Xu, Wenxuan; Liu, Yajuan; Ye, Yanxin; Liu, Meng; Han, Laichuang; Song, Andong; Liu, Liangwei

2016-10-01

The 9_2 carbohydrate-binding module (C2) locates natively at the C-terminus of the GH10 thermophilic xylanase from Thermotoga marimita. When fused to the C-terminus, C2 improved thermostability of a GH11 xylanase (Xyn) from Aspergillus niger. However, a question is whether the C-terminal C2 would have a thermostabilizing effect when fused to the N-terminus of a catalytic module. A chimeric enzyme, C2-Xyn, was created by step-extension PCR, cloned in pET21a(+), and expressed in E. coli BL21(DE3). The C2-Xyn exhibited a 2 °C higher optimal temperature, a 2.8-fold longer thermostability, and a 4.5-fold higher catalytic efficiency on beechwood xylan than the Xyn. The C2-Xyn exhibited a similar affinity for binding to beechwood xylan and a higher affinity for oat-spelt xylan than Xyn. C2 is a thermostabilizing carbohydrate-binding module and provides a model of fusion at an enzymatic terminus inconsistent with the modular natural terminal location.

4-alkyl-L-(Dehydro)proline biosynthesis in actinobacteria involves N-terminal nucleophile-hydrolase activity of γ-glutamyltranspeptidase homolog for C-C bond cleavage

Science.gov (United States)

Zhong, Guannan; Zhao, Qunfei; Zhang, Qinglin; Liu, Wen

2017-07-01

γ-Glutamyltranspeptidases (γ-GTs), ubiquitous in glutathione metabolism for γ-glutamyl transfer/hydrolysis, are N-terminal nucleophile (Ntn)-hydrolase fold proteins that share an autoproteolytic process for self-activation. γ-GT homologues are widely present in Gram-positive actinobacteria where their Ntn-hydrolase activities, however, are not involved in glutathione metabolism. Herein, we demonstrate that the formation of 4-Alkyl-L-(dehydro)proline (ALDP) residues, the non-proteinogenic α-amino acids that serve as vital components of many bioactive metabolites found in actinobacteria, involves unprecedented Ntn-hydrolase activity of γ-GT homologue for C-C bond cleavage. The related enzymes share a key Thr residue, which acts as an internal nucleophile for protein hydrolysis and then as a newly released N-terminal nucleophile for carboxylate side-chain processing likely through the generation of an oxalyl-Thr enzyme intermediate. These findings provide mechanistic insights into the biosynthesis of various ALDP residues/associated natural products, highlight the versatile functions of Ntn-hydrolase fold proteins, and particularly generate interest in thus far less-appreciated γ-GT homologues in actinobacteria.

Crystal structure of bis(azido-κNbis[2,5-bis(pyridin-2-yl-1,3,4-thiadiazole-κ2N2,N3]cobalt(II

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Abdelhakim Laachir

2015-05-01

Full Text Available In the mononuclear title complex, [Co(N32(C12H8N4S2], the cobalt(II atom is located on an inversion centre and displays an axially weakly compressed octahedral coordination geometry. The equatorial positions are occupied by the N atoms of two 2,5-bis(pyridin-2-yl-1,3,4-thiadiazole ligands, whereas the axial positions are occupied by N atoms of the azide anions. The thiadiazole and pyridine rings linked to the metal are almost coplanar, with a maximum deviation from the mean plane of 0.0273 (16 Å. The cohesion of the crystal is ensured by weak C—H...N hydrogen bonds and by π–π interactions between pyridine rings [intercentroid distance = 3.6356 (11 Å], forming a layered arrangement parallel to (001. The structure of the title compound is isotypic with that of the analogous nickel(II complex [Laachir et al. (2013. Acta Cryst. E69, m351–m352].

Crystal structure of bis(azido-κNbis[2,5-bis(pyridin-2-yl-1,3,4-thiadiazole-κ2N2,N3]nickel(II

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Abdelhakim Laachir

2015-02-01

Full Text Available Reaction of 2,5-bis(pyridin-2-yl-1,3,4-thiadiazole and sodium azide with nickel(II triflate yielded the mononuclear title complex, [Ni(N32(C12H8N4S2]. The NiII ion is located on a centre of symmetry and is octahedrally coordinated by four N atoms of the two bidentate heterocyclic ligands in the equatorial plane. The axial positions are occupied by the N atoms of two almost linear azide ions [N—N—N = 178.8 (2°]. The thiadiazole and pyridine rings of the heterocyclic ligand are almost coplanar, with a maximum deviation from the mean plane of 0.0802 (9 Å. The cohesion of the crystal structure is ensured by π–π interactions between parallel pyridine rings of neighbouring molecules [centroid-to-centroid distance = 3.6413 (14 Å], leading to a layered arrangement of the molecules parallel to (001.

Acetylation of spermidine and methylglyoxal bis(guanylhydrazone) in baby-hamster kidney cells (BHK-21/C13).

Science.gov (United States)

Wallace, H M; Nuttall, M E; Robinson, F C

1988-01-01

Treatment of BHK-21/C13 cells with methylglyoxal bis(guanylhydrazone) (MGBG) induced the cytosolic form of spermidine N1-acetyltransferase. It stabilized the enzyme against proteolytic degradation, but the drug did not affect the enzyme activity in vitro. MGBG was itself acetylated by BHK-21/C13 cells, but at only one-tenth the rate at which spermidine was acetylated. Acetylation occurred almost exclusively in the nuclear fraction. The product was identified as N-acetyl-MGBG by h.p.l.c., by using [3H]acetyl-CoA and [14C]MGBG as co-substrates. The results suggest that the acetylation of MGBG by BHK-21/C13 cells occurs by a different acetyltransferase enzyme from that which acetylates spermidine. PMID:3421945

Induction of spermidine/spermine N1-acetyltransferase by methylglyoxal bis(guanylhydrazone).

Science.gov (United States)

Pegg, A E; Erwin, B G; Persson, L

1985-10-17

The anti-tumor agent methylglyoxal bis(guanylhydrazone) was found to be a competitive inhibitor of spermidine/spermine N1-acetyltransferase with a Ki of about 8 microM. Treatment of rats with this drug lead to a very large increase in the total amount of spermidine/spermine N1-acetyltransferase in liver, kidney and spleen. The total increase as measured using a specific antiserum amounted to 700-fold in liver and 100-fold in kidney within 18 h of treatment with 80 mg/kg doses. At least part of this induction was due to a pronounced increase in the half-life of the acetyltransferase which increased from 15 min to more than 12 h. The very large increase in the amount of the enzyme is likely to overwhelm the direct inhibition, and a net increase in the acetylation of polyamines by this enzyme would be expected to occur after treatment with methylglyoxal bis(guanylhydrazone). The acetylated polyamines are known to be rapidly degraded by polyamine oxidase producing putrescine. Direct evidence that a substantial part of the increase in the content of putrescine in the liver of rats treated with methylglyoxal bis(guanylhydrazone) occurs via the induction of this acetylase/oxidase pathway was obtained. These results indicate that methylglyoxal bis(guanylhydrazone) affects cellular polyamine levels not only by means of its inhibitory effect on S-adenosylmethionine decarboxylase and diamine oxidase but also by the induction of spermidine/spermine N1-acetyltransferase. They also raise the possibility that the enormous increase in this enzyme which occurs with higher doses may contribute to the very severe toxicity of methylglyoxal bis(guanylhydrazone).

Convenient synthesis of [2-{sup 14}C]-methylglyoxal bis(guanylhydrazone), [{sup 14}C]-mitoguazone

Energy Technology Data Exchange (ETDEWEB)

Burgos, A.; Ellames, G.J. [Sterling Winthrop Research Centre, Alnwick (United Kingdom). Pharmaceuticals Research Div.

1995-01-01

[2-{sup 14}C]-Methylglyoxal bis(guanylhydrazone) dihydrochloride, [{sup 14}C]-mitoguazone has been prepared in three steps from potassium[1-{sup 14}C]-acetate in an overall radiochemical yield of 16%. The key steps in this procedure are the formation of the sodium salt of[acetone-2-{sup 14}C]-methylsulfinylacetone, and Pummerer rearrangement to the [{sup 14}C] labelled hermithioacetal, which is trapped with two equivalents of aminoguanidine to afford the desired [{sup 14}C]-mitoguazone. (Author).

GBNV encoded movement protein (NSm) remodels ER network via C-terminal coiled coil domain

Energy Technology Data Exchange (ETDEWEB)

Singh, Pratibha; Savithri, H.S., E-mail: bchss@biochem.iisc.ernet.in

2015-08-15

Plant viruses exploit the host machinery for targeting the viral genome–movement protein complex to plasmodesmata (PD). The mechanism by which the non-structural protein m (NSm) of Groundnut bud necrosis virus (GBNV) is targeted to PD was investigated using Agrobacterium mediated transient expression of NSm and its fusion proteins in Nicotiana benthamiana. GFP:NSm formed punctuate structures that colocalized with mCherry:plasmodesmata localized protein 1a (PDLP 1a) confirming that GBNV NSm localizes to PD. Unlike in other movement proteins, the C-terminal coiled coil domain of GBNV NSm was shown to be involved in the localization of NSm to PD, as deletion of this domain resulted in the cytoplasmic localization of NSm. Treatment with Brefeldin A demonstrated the role of ER in targeting GFP NSm to PD. Furthermore, mCherry:NSm co-localized with ER–GFP (endoplasmic reticulum targeting peptide (HDEL peptide fused with GFP). Co-expression of NSm with ER–GFP showed that the ER-network was transformed into vesicles indicating that NSm interacts with ER and remodels it. Mutations in the conserved hydrophobic region of NSm (residues 130–138) did not abolish the formation of vesicles. Additionally, the conserved prolines at positions 140 and 142 were found to be essential for targeting the vesicles to the cell membrane. Further, systematic deletion of amino acid residues from N- and C-terminus demonstrated that N-terminal 203 amino acids are dispensable for the vesicle formation. On the other hand, the C-terminal coiled coil domain when expressed alone could also form vesicles. These results suggest that GBNV NSm remodels the ER network by forming vesicles via its interaction through the C-terminal coiled coil domain. Interestingly, NSm interacts with NP in vitro and coexpression of these two proteins in planta resulted in the relocalization of NP to PD and this relocalization was abolished when the N-terminal unfolded region of NSm was deleted. Thus, the NSm

c-fos/c-jun expression and AP-1 activation in skin fibroblasts from centenarians.

Science.gov (United States)

Grassilli, E; Bellesia, E; Salomoni, P; Croce, M A; Sikora, E; Radziszewska, E; Tesco, G; Vergelli, M; Latorraca, S; Barbieri, D; Fagiolo, U; Santacaterina, S; Amaducci, L; Tiozzo, R; Sorbi, S; Franceschi, C

1996-09-13

In vitro replicative senescence is characterized by an irreversible growth arrest due to the inability of the cell to induce some key regulators of cell cycle progression, such as c-fos and AP-1, in response to mitogenic stimuli. In vitro replicative senescence and in vivo aging have been assumed to be two related phenomena, likely controlled by overlapping or interacting genes. As a corollary, fibroblasts from centenarians, which have undergone a long process of senescence in vivo should have very limited proliferative capability. On the contrary, in a previous work we found that fibroblasts from centenarians exhibited the same capacity to respond to different mitogenic stimuli as fibroblasts from young donors. Here we provide evidences that the well preserved proliferative response is likely due to the fact that some pivotal regulators- c-fos, c-jun and AP-1-are still fully inducible, despite a long process of in vivo senescence. Our data therefore suggest that in vivo and in vitro aging are separate phenomena whose possible relationships, if any, have to be ascertained very carefully.

The first N-terminal unprotected (Gly-Aib)n peptide: H-Gly-Aib-Gly-Aib-OtBu.

Science.gov (United States)

Gessmann, Renate; Brückner, Hans; Petratos, Kyriacos

2015-12-01

Glycine (Gly) is incorporated in roughly half of all known peptaibiotic (nonribosomally biosynthesized antibiotic peptides of fungal origin) sequences and is the residue with the greatest conformational flexibility. The conformational space of Aib (α-aminoisobutyric acid) is severely restricted by the second methyl group attached to the Cα atom. Most of the crystal structures containing Aib are N-terminal protected. Deprotection of the N- or C-terminus of peptides may alter the hydrogen-bonding scheme and/or the structure and may facilitate crystallization. The structure reported here for glycyl-α-aminoisobutyrylglycyl-α-aminoisobutyric acid tert-butyl ester, C16H30N4O5, describes the first N-terminal-unprotected (Gly-Aib)n peptide. The achiral peptide could form an intramolecular hydrogen bond between the C=O group of Gly1 and the N-H group of Aib4. This hydrogen bond is found in all tetrapeptides and N-terminal-protected tripeptides containing Aib, apart from one exception. In the present work, this hydrogen bond is not observed (N...O = 5.88 Å). Instead, every molecule is hydrogen bonded to six other symmetry-related molecules with a total of eight hydrogen bonds per molecule. The backbone conformation starts in the right-handed helical region (and the left-handed helical region for the inverted molecule) and reverses the screw sense in the last two residues.

Identification of a c-Jun N-terminal kinase-2-dependent signal amplification cascade that regulates c-Myc levels in ras transformation

DEFF Research Database (Denmark)

Mathiasen, D.P.; Egebjerg, C.; Andersen, S.H.

2012-01-01

are essential for ras transformation. Previous studies show that ERK-mediated serine 62 phosphorylation protects c-Myc from proteasomal degradation. ERK is, however, not alone sufficient to stabilize c-Myc but requires the cooperation of cancerous inhibitor of protein phosphatase 2A (CIP2A), an oncogene...... that counteracts protein phosphatase 2A-mediated dephosphorylation of c-Myc. Here we show that JNK2 regulates Cip2a transcription via ATF2. ATF2 and c-Myc cooperate to activate the transcription of ATF3. Remarkably, not only ectopic JNK2, but also ectopic ATF2, CIP2A, c-Myc and ATF3 are sufficient to rescue...... the defective ras transformation of JNK2-deficient cells. Thus, these data identify the key signal converging point of JNK2 and ERK pathways and underline the central role of CIP2A in ras transformation.Oncogene advance online publication, 27 June 2011; doi:10.1038/onc.2011.230....

Novel organic NLO material bis(N-phenylbiguanidium(1+)) oxalate - A combined X-ray diffraction, DSC and vibrational spectroscopic study of its unique polymorphism

Science.gov (United States)

Matulková, Irena; Císařová, Ivana; Vaněk, Přemysl; Němec, Petr; Němec, Ivan

2017-01-01

Three polymorphic modifications of bis(N-phenylbiguanidium(1+)) oxalate are reported, and their characterization is discussed in this paper. The non-centrosymmetric bis(N-phenylbiguanidium(1+)) oxalate (I), which was obtained from an aqueous solution at 313 K, belongs to the monoclinic space group Cc (a = 6.2560(2) Å, b = 18.6920(3) Å, c = 18.2980(5) Å, β = 96.249(1)°, V = 2127.0(1) Å3, Z = 4, R = 0.0314 for 4738 observed reflections). The centrosymmetric bis(N-phenylbiguanidium(1+)) oxalate (II) was obtained from an aqueous solution at 298 K and belongs to the monoclinic space group P21/n (a = 6.1335(3) Å, b = 11.7862(6) Å, c = 14.5962(8) Å, β = 95.728(2)°, V = 1049.90(9) Å3, Z = 4, R = 0.0420 for 2396 observed reflections). The cooling of the centrosymmetric phase (II) leads to the formation of bis(N-phenylbiguanidium(1+)) oxalate (III) (a = 6.1083(2) Å, b = 11.3178(5) Å, c = 14.9947(5) Å, β = 93.151(2)°, V = 1035.05(8) Å3, Z = 4, R = 0.0345 for 2367 observed reflections and a temperature of 110 K), which also belongs to the monoclinic space group P21/n. The crystal structures of the three characterized phases are generally based on layers of isolated N-phenylbiguanidium(1 +) cations separated by oxalate anions and interconnected with them by several types of N-H...O hydrogen bonds. The observed phases generally differ not only in their crystal packing but also in the lengths and characteristics of their hydrogen bonds. The thermal behaviour of the prepared compounds was studied using the DSC method in the temperature range from 90 K up to a temperature near the melting point of each crystal. The bis(N-phenylbiguanidium(1+)) oxalate (II) crystals exhibit weak reversible thermal effects on the DSC curve at 147 K (heating run). Further investigation of this effect, which was assigned to the isostructural phase transformation, was performed using FTIR, Raman spectroscopy and X-ray diffraction analysis in a wide temperature range.

Pregnane and Xenobiotic Receptor gene expression in liver cells is modulated by Ets-1 in synchrony with transcription factors Pax5, LEF-1 and c-jun

Energy Technology Data Exchange (ETDEWEB)

Kumari, Sangeeta; Saradhi, Mallampati; Rana, Manjul; Chatterjee, Swagata [Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067 (India); Aumercier, Marc [IRI, CNRS USR 3078, Université de Lille-Nord de France, Parc CNRS de la Haute Borne, 50 Avenue de Halley, BP 70478, 59658 Villeneuve d’Ascq Cedex (France); Mukhopadhyay, Gauranga [Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067 (India); Tyagi, Rakesh K., E-mail: rktyagi@yahoo.com [Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067 (India)

2015-01-15

Nuclear receptor PXR is predominantly expressed in liver and intestine. Expression of PXR is observed to be dysregulated in various metabolic disorders indicating its involvement in disease development. However, information available on mechanisms of PXR self-regulation is fragmentary. The present investigation identifies some of the regulatory elements responsible for its tight regulation and low cellular expression. Here, we report that the PXR-promoter is a target for some key transcription factors like PU.1/Ets-1, Pax5, LEF-1 and c-Jun. Interestingly, we observed that PXR-promoter responsiveness to Pax5, LEF-1 and c-Jun, is considerably enhanced by Ets transcription factors (PU.1 and Ets-1). Co-transfection of cells with Ets-1, LEF-1 and c-Jun increased PXR-promoter activity by 5-fold and also induced expression of endogenous human PXR. Site-directed mutagenesis and transfection studies revealed that two Ets binding sites and two of the three LEF binding sites in the PXR-promoter are functional and have a positive effect on PXR transcription. Results suggest that expression of Ets family members, in conjunction with Pax5, LEF-1 and c-Jun, lead to coordinated up-regulation of PXR gene transcription. Insights obtained on the regulation of PXR gene have relevance in offering important cues towards normal functioning as well as development of several metabolic disorders via PXR signaling. - Highlights: • The study identified cis-regulatory elements in the nuclear receptor PXR promoter. • Several trans-acting factors modulating the PXR-promoter have been identified. • PU.1/Ets-1, Pax5, LEF-1, c-Jun, LyF-VI and NF-1 act as modulators of the PXR-promoter. • Ets-1 in conjunction with LEF-1 and c-Jun exhibit 5-fold activation of the PXR-promoter. • Insights into PXR-regulation have relevance in normal and pathological conditions.

The C-Terminal O-S Acyl Shift Pathway under Acidic Condition to Propose Peptide-Thioesters

Directory of Open Access Journals (Sweden)

Bo Mi Kim

2016-11-01

Full Text Available Peptide-thioester is a pivotal intermediate for peptide ligation and N-, C-terminal cyclization. In this study, desired pathway and the side products of two C-terminal handles, hydroxyethylthiol (HET and hydroxypropylthiol (HPT are described in different conditions as well as kinetic studies. In addition, a new mechanism of C-terminal residue racemization is proposed on the basis of differentiation of products derived from the two C-terminal handles in preparing peptide thioesters through an acid-catalyzed tandem thiol switch, first by an intramolecular O-S acyl shift, and then by an intermolecular S-S exchange.

Crystal structure of a looped-chain CoII coordination polymer: catena-poly[[bis-(nitrato-κO)cobalt(II)]bis-[μ-bis-(pyridin-3-ylmeth-yl)sulfane-κ2N:N'

Science.gov (United States)

Moon, Suk-Hee; Seo, Joobeom; Park, Ki-Min

2017-11-01

The asymmetric unit of the title compound, [Co(NO 3 ) 2 (C 12 H 12 N 2 S) 2 ] n , contains a bis-(pyridin-3-ylmeth-yl)sulfane ( L ) ligand, an NO 3 - anion and half a Co II cation, which lies on an inversion centre. The Co II cation is six-coordinated, being bound to four pyridine N atoms from four symmetry-related L ligands. The remaining coordination sites are occupied by two O atoms from two symmetry-related nitrate anions in a monodentate manner. Thus, the Co II centre adopts a distorted octa-hedral geometry. Two symmetry-related L ligands are connected by two symmetry-related Co II cations, forming a 20-membered cyclic dimer, in which the Co II atoms are separated by 10.2922 (7) Å. The cyclic dimers are connected to each other by sharing Co II atoms, giving rise to the formation of an infinite looped chain propagating along the [101] direction. Inter-molecular C-H⋯π (H⋯ring centroid = 2.89 Å) inter-actions between one pair of corresponding L ligands and C-H⋯O hydrogen bonds between the L ligands and the nitrate anions occur in the looped chain. In the crystal, adjacent looped chains are connected by inter-molecular π-π stacking inter-actions [centroid-to-centroid distance = 3.8859 (14) Å] and C-H⋯π hydrogen bonds (H⋯ring centroid = 2.65 Å), leading to the formation of layers parallel to (101). These layers are further connected through C-H⋯O hydrogen bonds between the layers, resulting in the formation of a three-dimensional supra-molecular architecture.

c-Jun/AP-1 pathway-mediated cyclin D1 expression participates in low dose arsenite-induced transformation in mouse epidermal JB6 Cl41 cells

International Nuclear Information System (INIS)

Zhang Dongyun; Li Jingxia; Gao Jimin; Huang Chuanshu

2009-01-01

Arsenic is a well-documented human carcinogen associated with skin carcinogenesis. Our previous work reveals that arsenite exposure is able to induce cell transformation in mouse epidermal cell JB6 Cl41 through the activation of ERK, rather than JNK pathway. Our current studies further evaluate downstream pathway in low dose arsenite-induced cell transformation in JB6 Cl41 cells. Our results showed that treatment of cells with low dose arsenite induced activation of c-Jun/AP-1 pathway, and ectopic expression of dominant negative mutant of c-Jun (TAM67) blocked arsenite-induced transformation. Furthermore, our data indicated that cyclin D1 was an important downstream molecule involved in c-Jun/AP-1-mediated cell transformation upon low dose arsenite exposure, because inhibition of cyclin D1 expression by its specific siRNA in the JB6 Cl41 cells resulted in impairment of anchorage-independent growth of cells induced by low dose arsenite. Collectively, our results demonstrate that c-Jun/AP-1-mediated cyclin D1 expression is at least one of the key events implicated in cell transformation upon low dose arsenite exposure

Comportamiento de la eficiencia de los gobiernos locales de Junín mediante el análisis envolvente de datos

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Ybnias Grijalva Yauri

2015-12-01

Full Text Available La investigación comprende el análisis de los niveles de eficiencia de los gobiernos locales de la región Junín, período 2009 - 2014, mediante el método de análisis envolvente de datos (DEA y el índice de Malmquist, que se aplican buscando el objetivo de identificar un conjunto de unidades de eficiencia que sirvan de referente a los gobiernos locales de la región y así impulsar el cumplimiento de la misión institucional y de las competencias de gobierno local y por ende promover el desarrollo integral de su jurisdicción . La hipótesis planteada fue que los gobiernos locales que reporten niveles de eficiencia alcanzarán el cumplimiento de su misión institucional y sus competencias así como el cumplimiento de sus funciones, logrando promover el desarrollo integral de su jurisdicción. Los resultados obtenidos, en función de tres competencias de los gobiernos locales (servicios públicos locales; organización del espacio físico y uso del suelo; servicios sociales locales, indican que los gobiernos locales de Junín no alcanzan niveles de eficiencia permanentes en el tiempo. En conclusión, no es posible identificar unidades de toma de decisiones (DMU de eficiencia que sirvan como referencia a los gobiernos locales de Junín, limitando el cumplimiento de su misión institucional y cabal desempeño de competencias y funciones, en desmedro del desarrollo económico y social de su jurisdicción.

The C-Terminal RpoN Domain of sigma54 Forms an unpredictedHelix-Turn-Helix Motif Similar to domains of sigma70

Energy Technology Data Exchange (ETDEWEB)

Doucleff, Michaeleen; Malak, Lawrence T.; Pelton, Jeffrey G.; Wemmer, David E.

2005-11-01

The ''{delta}'' subunit of prokaryotic RNA-polymerase allows gene-specific transcription initiation. Two {sigma} families have been identified, {sigma}{sup 70} and {sigma}{sup 54}, which use distinct mechanisms to initiate transcription and share no detectable sequence homology. Although the {sigma}{sup 70}-type factors have been well characterized structurally by x-ray crystallography, no high-resolution structural information is available for the {sigma}{sup 54}-type factors. Here we present the NMR derived structure of the C-terminal domain of {sigma}{sup 54} from Aquifex aeolicus. This domain (Thr323 to Gly389), which contains the highly conserved RpoN box sequence, consists of a poorly structured N-terminal tail followed by a three-helix bundle, which is surprisingly similar to domains of the {sigma}{sup 70}-type proteins. Residues of the RpoN box, which have previously been shown to be critical for DNA binding, form the second helix of an unpredicted helix-turn-helix motif. This structure's homology with other DNA binding proteins, combined with previous biochemical data, suggest how the C-terminal domain of {sigma}{sup 54} binds to DNA.

Crystal structures of eight 3D molecular adducts derived from bis-imidazole, bis(benzimidazole), and organic acids

Science.gov (United States)

Ding, Aihua; Jin, Shouwen; Jin, Shide; Hu, KaiKai; Lin, Zhihao; Liu, Hui; Wang, Daqi

2018-01-01

Cocrystallization of the bis(imidazole)/bis(benzimidazole) with a series of organic acids gave a total of eight molecular adducts with the compositions: (3,6-bis(imidazole-1-yl)pyridazine): (trichloroacetic acid)2(1) [(H2L1)2+ · (tca-)2, L1 = 3,6-bis(imidazole-1-yl)pyridazine, tca- = trichloroacetate], (bis(N-imidazolyl)methane): (suberic acid) (2) [(L2) · (H2suba), L2 = bis(N-imidazolyl)methane, H2suba = suberic acid], bis(N-imidazolyl)methane: (3-nitrophthalic acid): 3H2O (3) [(H2L2)2+ · (3-Hnpa-)2 · 3H2O, 3-Hnpa- = 3-nitro hydrogenphthalate], (bis(N-imidazolyl)butane)0.5: (4-nitrophthalic acid): H2O (4) [(H2L3)0.5+ · (4-Hnpa-)- · H2O, L3 = bis(N-imidazolyl)butane, 4-Hnpa- = 4-nitro hydrogenphthalate], (1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole): (3,5-dinitrosalicylic acid) (5) [(HL4) · (3,5-dns-), L4 = 1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole, 3,5-dns- = 3,5-dinitrosalicylate], (1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole): (3-nitrophthalic acid) (6) [(H2L4) · (3-npa2-), L4 = 1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole, 3-npa2-=3-nitrogenphthalate], (bis(N-imidazolyl)butane): (pamoic acid) (7) [(H2L3) · (pam), pam = pamoate], and (3,6-bis(imidazole-1-yl)pyridazine): (1,5-naphthalenedisulfonic acid) [(H2L1)2+ · (npda)2- = 1,5-naphthalenedisulfonate] (8). The eight adducts have been characterized by X-ray diffraction technique, infrared spectrum, and elemental analysis, and the melting points of all adducts were also reported. And their structural and supramolecular aspects are fully analyzed. The result reveals that among the eight investigated crystals both the end ring N in the bis(imidazole) moieties are protonated when the organic acids are deprotonated except 2, and 5, and the crystal packing is interpreted in terms of the strong ionic Nsbnd H⋯O H-bond between the imidazolium and the deprotonated acidic groups. Except the Nsbnd H⋯O H-bond, the Osbnd H⋯O H-bonds were also found at the salts 3, 4

The leucine zipper domains of the transcription factors GCN4 and c-Jun have ribonuclease activity.

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Yaroslav Nikolaev

Full Text Available Basic-region leucine zipper (bZIP proteins are one of the largest transcription factor families that regulate a wide range of cellular functions. Owing to the stability of their coiled coil structure leucine zipper (LZ domains of bZIP factors are widely employed as dimerization motifs in protein engineering studies. In the course of one such study, the X-ray structure of the retro-version of the LZ moiety of yeast transcriptional activator GCN4 suggested that this retro-LZ may have ribonuclease activity. Here we show that not only the retro-LZ but also the authentic LZ of GCN4 has weak but distinct ribonuclease activity. The observed cleavage of RNA is unspecific, it is not suppressed by the ribonuclease A inhibitor RNasin and involves the breakage of 3',5'-phosphodiester bonds with formation of 2',3'-cyclic phosphates as the final products as demonstrated by HPLC/electrospray ionization mass spectrometry. Several mutants of the GCN4 leucine zipper are catalytically inactive, providing important negative controls and unequivocally associating the enzymatic activity with the peptide under study. The leucine zipper moiety of the human factor c-Jun as well as the entire c-Jun protein are also shown to catalyze degradation of RNA. The presented data, which was obtained in the test-tube experiments, adds GCN4 and c-Jun to the pool of proteins with multiple functions (also known as moonlighting proteins. If expressed in vivo, the endoribonuclease activity of these bZIP-containing factors may represent a direct coupling between transcription activation and controlled RNA turnover. As an additional result of this work, the retro-leucine zipper of GCN4 can be added to the list of functional retro-peptides.

The Lectin Domain of the Polypeptide GalNAc Transferase Family of Glycosyltransferases (ppGalNAc Ts) Acts as a Switch Directing Glycopeptide Substrate Glycosylation in an N- or C-terminal Direction, Further Controlling Mucin Type O-Glycosylation

DEFF Research Database (Denmark)

Gerken, Thomas A; Revoredo, Leslie; Thome, Joseph J C

2013-01-01

and specificity that differ between transferase isoforms. For example, ppGalNAc T1, T2, and T14 prefer C-terminally placed GalNAc-O-Thr, whereas ppGalNAc T3 and T6 prefer N-terminally placed GalNAc-O-Thr. Several transferase isoforms, ppGalNAc T5, T13, and T16, display equally enhanced N- or C-terminal activities...... relative to the nonglycosylated control peptides. This N- and/or C-terminal selectivity is presumably due to weak glycopeptide binding to the lectin domain, whose orientation relative to the catalytic domain is dynamic and isoform-dependent. Such N- or C-terminal glycopeptide selectivity provides...

Phenyl Saligenin Phosphate Induced Caspase-3 and c-Jun N-Terminal Kinase Activation in Cardiomyocyte-Like Cells.

Science.gov (United States)

Felemban, Shatha G; Garner, A Christopher; Smida, Fathi A; Boocock, David J; Hargreaves, Alan J; Dickenson, John M

2015-11-16

At present, little is known about the effect(s) of organophosphorous compounds (OPs) on cardiomyocytes. In this study, we have investigated the effects of phenyl saligenin phosphate (PSP), two organophosphorothioate insecticides (diazinon and chlorpyrifos), and their acutely toxic metabolites (diazoxon and chlorpyrifos oxon) on mitotic and differentiated H9c2 cardiomyoblasts. OP-induced cytotoxicity was assessed by monitoring MTT reduction, LDH release, and caspase-3 activity. Cytotoxicity was not observed with diazinon, diazoxon, or chlorpyrifos oxon (48 h exposure; 200 μM). Chlorpyrifos-induced cytotoxicity was only evident at concentrations >100 μM. In marked contrast, PSP displayed pronounced cytotoxicity toward mitotic and differentiated H9c2 cells. PSP triggered the activation of JNK1/2 but not ERK1/2, p38 MAPK, or PKB, suggesting a role for this pro-apoptotic protein kinase in PSP-induced cell death. The JNK1/2 inhibitor SP 600125 attenuated PSP-induced caspase-3 and JNK1/2 activation, confirming the role of JNK1/2 in PSP-induced cytotoxicity. Fluorescently labeled PSP (dansylated PSP) was used to identify novel PSP binding proteins. Dansylated PSP displayed cytotoxicity toward differentiated H9c2 cells. 2D-gel electrophoresis profiles of cells treated with dansylated PSP (25 μM) were used to identify proteins fluorescently labeled with dansylated PSP. Proteomic analysis identified tropomyosin, heat shock protein β-1, and nucleolar protein 58 as novel protein targets for PSP. In summary, PSP triggers cytotoxicity in differentiated H9c2 cardiomyoblasts via JNK1/2-mediated activation of caspase-3. Further studies are required to investigate whether the identified novel protein targets of PSP play a role in the cytotoxicity of this OP, which is usually associated with the development of OP-induced delayed neuropathy.

Electronic structure evolution and energy level alignment at C60/4,4'-cyclohexylidenebis[N,N-bis(4-methylphenyl) benzenamine]/MoOx/indium tin oxide interfaces

Science.gov (United States)

Liu, Xiaoliang; Yi, Shijuan; Wang, Chenggong; Wang, Congcong; Gao, Yongli

2014-04-01

The electronic structure evolution and energy level alignment have been investigated at interfaces comprising fullerene (C60)/4,4'-cyclohexylidenebis[N,N-bis(4-methylphenyl) benzenamine] (TAPC)/ molybdenum oxide (MoOx)/ indium tin oxide with ultraviolet photoemission spectroscopy and inverse photoemission spectroscopy. With deposition of TAPC upon MoOx, a dipole of 1.58 eV was formed at the TAPC/MoOx interface due to electron transfer from TAPC to MoOx. The highest occupied molecular orbital (HOMO) onset of TAPC was pinned closed to the Fermi level, leading to a p-doped region and thus increasing the carrier concentration at the very interface. The downward band bending and the resulting built-in field in TAPC were favorable for the hole transfer toward the TAPC/MoOx interface. The rigid downward shift of energy levels of TAPC indicated no significant interface chemistry at the interface. With subsequent deposition of C60 on TAPC, a dipole of 0.27 eV was observed at the C60/TAPC heterojunction due to the electron transfer from TAPC to C60. This led to a drop of the HOMO of TAPC near the C60/TAPC interface, and hence further enhanced the band bending in TAPC. The band bending behavior was also observed in C60, similarly creating a built-in field in C60 film and improving the electron transfer away from the C60/TAPC interface. It can be deduced from the interface analysis that a promising maximum open circuit voltage of 1.5 eV is achievable in C60/TAPC-based organic photovoltaic cells.

Epimerization-free C-terminal peptide activation, elongation and cyclization

NARCIS (Netherlands)

Popović, S.

2015-01-01

C-terminal peptide activation and cyclization reactions are generally accompanied with epimerization (partial loss of C‐terminal stereointegrity). Therefore, the focus of this thesis was to develop epimerization-free methods for C-terminal peptide activation to enable C-terminal peptide elongation

Conformational and functional analysis of the C-terminal globular head of the reovirus cell attachment protein.

Science.gov (United States)

Duncan, R; Horne, D; Strong, J E; Leone, G; Pon, R T; Yeung, M C; Lee, P W

1991-06-01

We have been investigating structure-function relationships in the reovirus cell attachment protein sigma 1 using various deletion mutants and protease analysis. In the present study, a series of deletion mutants were constructed which lacked 90, 44, 30, 12, or 4 amino acids from the C-terminus of the 455-amino acid-long reovirus type 3 (T3) sigma 1 protein. The full-length and truncated sigma 1 proteins were expressed in an in vitro transcription/translation system and assayed for L cell binding activity. It was found that the removal of as few as four amino acids from the C-terminus drastically affected the cell binding function of the sigma 1 protein. The C-terminal-truncated proteins were further characterized using trypsin, chymotrypsin, and monoclonal and polyclonal antibodies. Our results indicated that the C-terminal portions of the mutant proteins were misfolded, leading to a loss in cell binding function. The N-terminal fibrous tail of the proteins was unaffected by the deletions as was sigma 1 oligomerization, further illustrating the discrete structural and functional roles of the N- and C-terminal domains of sigma 1. In an attempt to identify smaller, functional peptides, full-length sigma 1 expressed in vitro was digested with trypsin and subsequently with chymotrypsin under various conditions. The results clearly demonstrated the highly stable nature of the C-terminal globular head of sigma 1, even when separated from the N-terminal fibrous tail. We concluded that: (1) the C-terminal globular head of sigma 1 exists as a compact, protease-resistant oligomeric structure; (2) an intact C-terminus is required for proper head folding and generation of the conformationally dependent cell binding domain.

33 CFR 334.450 - Cape Fear River and tributaries at Sunny Point Army Terminal, Brunswick County, N.C.; restricted...

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2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Cape Fear River and tributaries... AND RESTRICTED AREA REGULATIONS § 334.450 Cape Fear River and tributaries at Sunny Point Army Terminal, Brunswick County, N.C.; restricted area. (a) The area. That portion of Cape Fear River due west of the main...

Crystal Structure of N,N-bis-(3-Carbomethoxy-5-methyl-pyrazol-1-ylmethylaniline

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Taibi Ben-Hadda

2002-09-01

Full Text Available The tripodal ligand N,N-bis-(3-carbomethoxy-5-methylpyrazol-1-ylmethyl aniline (2 has been prepared by the condensation of aniline with two equivalents of N-hydroxymethyl[3-carbomethoxy-5-methyl]pyrazole. The molecule consists of two structurally analogous 3-carbomethoxy-5-methylpyrazol-1-ylmethyl moieties, which adopt a transoidal conformation via a central aniline ring, suggesting that this tripodal ligand is highly flexible and could accommodate many metals by coordination.

Reactivity of the parent amido complexes of iridium with olefins: C-NH2 bond formation versus C-H activation.

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Mena, Inmaculada; García-Orduña, Pilar; Polo, Víctor; Lahoz, Fernando J; Casado, Miguel A; Oro, Luis A

2017-08-29

Herein we report on the different chemical reactivity displayed by two mononuclear terminal amido compounds depending on the nature of the coordinated diene. Hence, treatment of amido-bridged iridium complexes [{Ir(μ-NH 2 )(tfbb)} 3 ] (1; tfbb = tetrafluorobenzobarrelene) with dppp (dppp = bis(diphenylphosphane)propane) leads to the rupture of the amido bridges forming the mononuclear terminal amido compound [Ir(NH 2 )(dppp)(tfbb)] (3) in the first stage. On changing the reaction conditions, the formation of a C-NH 2 bond between the amido moiety and the coordinated diene is observed and a new dinuclear complex [{Ir(1,2-η 2 -4-κ-C 12 H 8 F 4 N)(dppp)} 2 (μ-dppp)] (4) has been isolated. On the contrary, the diiridium amido-bridged complex [{Ir(μ-NH 2 )(cod)} 2 ] (2; cod = 1,5-cyclooctadiene) in the presence of dppb (dppb = bis(diphenylphosphane)butane) allows the isolation of a mononuclear complex [Ir(1,2,3-η 3 -6-κ-C 8 H 10 )H(dppb)] (5), as a consequence of the extrusion of ammonia. The monitoring of the reaction of 2 with dppb (and dppp) allowed us to detect terminal amido complexes [Ir(NH 2 )(P-P)(cod)] (P-P = dppb (6), dppp (7)) in solution, as confirmed by an X-ray analysis of 7. Complex 7 was observed to evolve into hydrido species 5 at room temperature. DFT studies showed that C-H bond activation occurs through the deprotonation of one methylene fragment of the cod ligand by the highly basic terminal amido moiety instead of C-H oxidative addition to the Ir(i) center.

Activity of the C-terminal-dependent vacuolar sorting signal of horseradish peroxidase C1a is enhanced by its secondary structure.

Science.gov (United States)

Matsui, Takeshi; Tabayashi, Ayako; Iwano, Megumi; Shinmyo, Atsuhiko; Kato, Ko; Nakayama, Hideki

2011-02-01

Plant class III peroxidase (PRX) catalyzes the oxidation and oxidative polymerization of a variety of phenolic compounds while reducing hydrogen peroxide. PRX proteins are classified into apoplast type and vacuole type based on the absence or the presence of C-terminal propeptides, which probably function as vacuolar sorting signals (VSSs). In this study, in order to improve our understanding of vacuole-type PRX, we analyzed regulatory mechanisms of vacuolar sorting of a model vacuole-type PRX, the C1a isozyme of horseradish (Armoracia rusticana) (HRP C1a). Using cultured transgenic tobacco cells and protoplasts derived from horseradish leaves, we characterized HRP C1a's VSS, which is a 15 amino acid C-terminal propeptide (C15). We found that the C-terminal hexapeptide of C15 (C6), which is well conserved among vacuole-type PRX proteins, forms the core of the C-terminal-dependent VSS. We also found that the function of C6 is enhanced by the remaining N-terminal part of C15 which probably folds into an amphiphilic α-helix.

C-Terminal Fluorescent Labeling Impairs Functionality of DNA Mismatch Repair Proteins

Science.gov (United States)

Brieger, Angela; Plotz, Guido; Hinrichsen, Inga; Passmann, Sandra; Adam, Ronja; Zeuzem, Stefan

2012-01-01

The human DNA mismatch repair (MMR) process is crucial to maintain the integrity of the genome and requires many different proteins which interact perfectly and coordinated. Germline mutations in MMR genes are responsible for the development of the hereditary form of colorectal cancer called Lynch syndrome. Various mutations mainly in two MMR proteins, MLH1 and MSH2, have been identified so far, whereas 55% are detected within MLH1, the essential component of the heterodimer MutLα (MLH1 and PMS2). Most of those MLH1 variants are pathogenic but the relevance of missense mutations often remains unclear. Many different recombinant systems are applied to filter out disease-associated proteins whereby fluorescent tagged proteins are frequently used. However, dye labeling might have deleterious effects on MutLα's functionality. Therefore, we analyzed the consequences of N- and C-terminal fluorescent labeling on expression level, cellular localization and MMR activity of MutLα. Besides significant influence of GFP- or Red-fusion on protein expression we detected incorrect shuttling of single expressed C-terminal GFP-tagged PMS2 into the nucleus and found that C-terminal dye labeling impaired MMR function of MutLα. In contrast, N-terminal tagged MutLαs retained correct functionality and can be recommended both for the analysis of cellular localization and MMR efficiency. PMID:22348133

C-terminal fluorescent labeling impairs functionality of DNA mismatch repair proteins.

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Angela Brieger

Full Text Available The human DNA mismatch repair (MMR process is crucial to maintain the integrity of the genome and requires many different proteins which interact perfectly and coordinated. Germline mutations in MMR genes are responsible for the development of the hereditary form of colorectal cancer called Lynch syndrome. Various mutations mainly in two MMR proteins, MLH1 and MSH2, have been identified so far, whereas 55% are detected within MLH1, the essential component of the heterodimer MutLα (MLH1 and PMS2. Most of those MLH1 variants are pathogenic but the relevance of missense mutations often remains unclear. Many different recombinant systems are applied to filter out disease-associated proteins whereby fluorescent tagged proteins are frequently used. However, dye labeling might have deleterious effects on MutLα's functionality. Therefore, we analyzed the consequences of N- and C-terminal fluorescent labeling on expression level, cellular localization and MMR activity of MutLα. Besides significant influence of GFP- or Red-fusion on protein expression we detected incorrect shuttling of single expressed C-terminal GFP-tagged PMS2 into the nucleus and found that C-terminal dye labeling impaired MMR function of MutLα. In contrast, N-terminal tagged MutLαs retained correct functionality and can be recommended both for the analysis of cellular localization and MMR efficiency.

Metformin prevents endoplasmic reticulum stress-induced apoptosis through AMPK-PI3K-c-Jun NH2 pathway

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Jung, T.W.; Lee, M.W.; Lee, Y.-J.; Kim, S.M.

2012-01-01

Type 2 diabetes mellitus is thought to be partially associated with endoplasmic reticulum (ER) stress toxicity on pancreatic beta cells and the result of decreased insulin synthesis and secretion. In this study, we showed that a well-known insulin sensitizer, metformin, directly protects against dysfunction and death of ER stress-induced NIT-1 cells (a mouse pancreatic beta cell line) via AMP-activated protein kinase (AMPK) and phosphatidylinositol-3 (PI3) kinase activation. We also showed that exposure of NIT-1 cells to metformin (5mM) increases cellular resistance against ER stress-induced NIT-1 cell dysfunction and death. AMPK and PI3 kinase inhibitors abolished the effect of metformin on cell function and death. Metformin-mediated protective effects on ER stress-induced apoptosis were not a result of an unfolded protein response or the induced inhibitors of apoptotic proteins. In addition, we showed that exposure of ER stressed-induced NIT-1 cells to metformin decreases the phosphorylation of c-Jun NH(2) terminal kinase (JNK). These data suggest that metformin is an important determinant of ER stress-induced apoptosis in NIT-1 cells and may have implications for ER stress-mediated pancreatic beta cell destruction via regulation of the AMPK-PI3 kinase-JNK pathway.

Activation of Tax protein by c-Jun-N-terminal kinase is not dependent on the presence or absence of the early growth response-1 gene product.

Science.gov (United States)

Parra, Eduardo; Gutierréz, Luís; Ferreira, Jorge

2016-02-01

The Tax protein of human T cell leukemia virus type 1 plays a major role in the pathogenesis of adult T cell leukemia (ATL), an aggressive neoplasia of CD4+ T cells. In the present study, we investigated whether the EGR-1 pathway is involved in the regulation of Tax-induced JNK expression in human Jurkat T cells transfected to express the Tax protein in the presence or absence of PMA or ionomycin. Overexpression of EGR-1 in Jurkat cells transfected to express Tax, promoted the activation of several genes, with the most potent being those that contained AP-1 (Jun/c-Fos), whereas knockdown of endogenous EGR-1 by small interfering RNA (siRNA) somewhat reduced Tax-mediated JNK-1 transcription. Additionally, luciferase-based AP-1 and NF-κB reporter gene assays demonstrated that inhibition of EGR-1 expression by an siRNA did not affect the transcriptional activity of a consensus sequence of either AP-1 or NF-κB. On the other hand, the apoptosis assay, using all-trans retinoic acid (ATRA) as an inducer of apoptosis, confirmed that siRNA against EGR-1 failed to suppress ATRA-induced apoptosis in Jurkat and Jurkat-Tax cells, as noted by the low levels of both DEVDase activity and DNA fragmentation, indicating that the induction of apoptosis by ATRA was Egr-1-independent. Finally, our data showed that activation of Tax by JNK-1 was not dependent on the EGR-1 cascade of events, suggesting that EGR-1 is important but not a determinant for the activity for Tax-induced proliferation of Jurkat cells.

Structure of the C-terminal effector-binding domain of AhrC bound to its corepressor l-arginine

International Nuclear Information System (INIS)

Garnett, James A.; Baumberg, Simon; Stockley, Peter G.; Phillips, Simon E. V.

2007-01-01

The crystal structure of the C-terminal domain hexameric core of AhrC, with bound corepressor (l-arginine), has been solved at 1.95 Å resolution. Binding of l-arginine results in a rotation between the two trimers of the hexamer, leading to the activation of the DNA-binding state. The arginine repressor/activator protein (AhrC) from Bacillus subtilis belongs to a large family of multifunctional transcription factors that are involved in the regulation of bacterial arginine metabolism. AhrC interacts with operator sites in the promoters of arginine biosynthetic and catabolic operons, acting as a transcriptional repressor at biosynthetic sites and an activator of transcription at catabolic sites. AhrC is a hexamer of identical subunits, each having two domains. The C-terminal domains form the core of the protein and are involved in oligomerization and l-arginine binding. The N-terminal domains lie on the outside of the compact core and play a role in binding to 18 bp DNA operators called ARG boxes. The C-terminal domain of AhrC has been expressed, purified and characterized, and also crystallized as a hexamer with the bound corepressor l-arginine. Here, the crystal structure refined to 1.95 Å is presented

[Expressiona of c-Jun and collagens I and III in cultured human skin fibroblasts are affected by infrared ray radiation].

Science.gov (United States)

Liu, Ping; Yang, Rong-Li; Su, Hui; Li, Lin-Li; Song, Jian-Wen; Lu, Ning; Liu, Yu-Ze

2016-02-01

To observe the effect of solar infrared ray (IR) radiation on the expressions of c-Jun and collagens I and III in cultured human skin fibroblasts (HSFs) and explore the molecular mechanism by which IR radiation causes aging of the skin. Primarily cultured HSFs exposed to IR radiation were examined for changes of the cell viability with MTT assay. The mRNA and protein expressions of c-Jun and collagens I and III was detected with real-time quantitative PCR and immunocytochemistry. MTT assay showed that IR irradiation caused inhibition of cell proliferation compared with the control cells. The mRNA and protein expression of collagen I was decreased significantly by IR irradiation with the increase of the irradiation dose (Pradiation to initiate and promote skin photoaging.

Andrographolide attenuates LPS-stimulated up-regulation of C-C and C-X-C motif chemokines in rodent cortex and primary astrocytes.

Science.gov (United States)

Wong, Siew Ying; Tan, Michelle G K; Banks, William A; Wong, W S Fred; Wong, Peter T-H; Lai, Mitchell K P

2016-02-09

Andrographolide is the major bioactive compound isolated from Andrographis paniculata, a native South Asian herb used medicinally for its anti-inflammatory properties. In this study, we aimed to assess andrographolide's potential utility as an anti-neuroinflammatory therapeutic. The effects of andrographolide on lipopolysaccharide (LPS)-induced chemokine up-regulation both in mouse cortex and in cultured primary astrocytes were measured, including cytokine profiling, gene expression, and, in cultured astrocytes, activation of putative signaling regulators. Orally administered andrographolide significantly attenuated mouse cortical chemokine levels from the C-C and C-X-C subfamilies. Similarly, andrographolide abrogated a range of LPS-induced chemokines as well as tumor necrosis factor (TNF)-α in astrocytes. In astrocytes, the inhibitory actions of andrographolide on chemokine and TNF-α up-regulation appeared to be mediated by nuclear factor-κB (NF-κB) or c-Jun N-terminal kinase (JNK) activation. These results suggest that andrographolide may be useful as a therapeutic for neuroinflammatory diseases, especially those characterized by chemokine dysregulation.

miR-138 protects cardiomyocytes from hypoxia-induced apoptosis via MLK3/JNK/c-jun pathway

Energy Technology Data Exchange (ETDEWEB)

He, Siyi; Liu, Peng; Jian, Zhao; Li, Jingwei; Zhu, Yun; Feng, Zezhou; Xiao, Yingbin, E-mail: xiaoyb@vip.sina.com

2013-11-29

Highlights: •First time to find miR-138 is up-regulated in hypoxic cardiomyocytes. •First time to find miR-138 targets MLK3 and regulates JNK/c-jun pathway. •Rare myocardial biopsy of patients with CHD were collected. •Both silence and overexpression of miR-138 were implemented. •Various methods were used to detect cell function. -- Abstract: Cardiomyocytes experience a series of complex endogenous regulatory mechanisms against apoptosis induced by chronic hypoxia. MicroRNAs are a class of endogenous small non-coding RNAs that regulate cellular pathophysiological processes. Recently, microRNA-138 (miR-138) has been found related to hypoxia, and beneficial for cell proliferation. Therefore, we intend to study the role of miR-138 in hypoxic cardiomyocytes and the main mechanism. Myocardial samples of patients with congenital heart disease (CHD) were collected to test miR-138 expression. Agomir or antagomir of miR-138 was transfected into H9C2 cells to investigate its effect on cell apoptosis. Higher miR-138 expression was observed in patients with cyanotic CHD, and its expression gradually increased with prolonged hypoxia time in H9C2 cells. Using MTT and LDH assays, cell growth was significantly greater in the agomir group than in the negative control (NC) group, while antagomir decreased cell survival. Dual luciferase reporter gene and Western-blot results confirmed MLK3 was a direct target of miR-138. It was found that miR-138 attenuated hypoxia-induced apoptosis using TUNEL, Hoechst staining and Annexin V-PE/7-AAD flow cytometry analysis. We further detected expression of apoptosis-related proteins. In the agomir group, the level of pro-apoptotic proteins such as cleaved-caspase-3, cleaved-PARP and Bad significantly reduced, while Bcl-2 and Bcl-2/Bax ratio increased. Opposite changes were observed in the antagomir group. Downstream targets of MLK3, JNK and c-jun, were also suppressed by miR-138. Our study demonstrates that up-regulation of miR-138 plays

Discovery of new molecular entities able to strongly interfere with Hsp90 C-terminal domain.

Science.gov (United States)

Terracciano, Stefania; Russo, Alessandra; Chini, Maria G; Vaccaro, Maria C; Potenza, Marianna; Vassallo, Antonio; Riccio, Raffaele; Bifulco, Giuseppe; Bruno, Ines

2018-01-26

Heat shock protein 90 (Hsp90) is an ATP dependent molecular chaperone deeply involved in the complex network of cellular signaling governing some key functions, such as cell proliferation and survival, invasion and angiogenesis. Over the past years the N-terminal protein domain has been fully investigated as attractive strategy against cancer, but despite the many efforts lavished in the field, none of the N-terminal binders (termed "classical inhibitors"), currently in clinical trials, have yet successfully reached the market, because of the detrimental heat shock response (HSR) that showed to induce; thus, recently, the selective inhibition of Hsp90 C-terminal domain has powerfully emerged as a more promising alternative strategy for anti-cancer therapy, not eliciting this cell rescue cascade. However, the structural complexity of the target protein and, mostly, the lack of a co-crystal structure of C-terminal domain-ligand, essential to drive the identification of new hits, represent the largest hurdles in the development of new selective C-terminal inhibitors. Continuing our investigations on the identification of new anticancer drug candidates, by using an orthogonal screening approach, here we describe two new potent C-terminal inhibitors able to induce cancer cell death and a considerable down-regulation of Hsp90 client oncoproteins, without triggering the undesired heat shock response.

[(Nitrato-κO,O')(nitrito-κO,O')(0.25/1.75)]bis-(1,10-phenanthroline-κN,N')cadmium(II).

Science.gov (United States)

Najafi, Ezzatollah; Amini, Mostafa M; Ng, Seik Weng

2011-01-22

The reaction of cadmium nitrate and sodium nitrite in the presence of 1,10-phenanthroline yields the mixed nitrate-nitrite title complex, [Cd(NO(2))(1.75)(NO(3))(0.25)(C(12)H(8)N(2))(2)]. The metal ion is bis-chelated by two N-heterocycles as well as by the nitrate/nitrite ions in a distorted dodeca-hedral CdN(4)O(4) coordination environment. One nitrite group is ordered; the other is disordered with respect to a nitrate group (ratio 0.75:0.25) concerning the O atom that is not involved in bonding to the metal ion.

Bis[(lprolinate-N,O]Zn: A water-soluble and recycle catalyst for various organic transformations

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Roona Poddar

2017-05-01

Full Text Available Under the green chemistry perspective, bis[(lprolinate-N,O]Zn (also called zinc–proline or Zn[(l-pro]2 has proven its competence as a promising alternative in a plethora of applications such as catalyst or promoter. Owing to its biodegradable and non-toxic nature of bis[(lprolinate-N,O]Zn, it is being actively investigated as a water soluble green catalyst for synthetic chemistry. Bis[(lprolinate-N,O]Zn are readily utilized under mild conditions and have high selectivity and reactivity with broad range of substrate acceptance to make it better reaction medium for a wide variety of organic transformations. This Review summarizes the till date literature on its synthesis, characterization, and its catalytic role in various organic reactions.

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.

Designing a Long Acting Erythropoietin by Fusing Three Carboxyl-Terminal Peptides of Human Chorionic Gonadotropin β Subunit to the N-Terminal and C-Terminal Coding Sequence

Directory of Open Access Journals (Sweden)

Fuad Fares

2011-01-01

Full Text Available A new analog of EPO was designed by fusing one and two CTPs to the N-terminal and C-terminal ends of EPO (EPO-(CTP3, respectively. This analog was expressed and secreted efficiently in CHO cells. The in vitro test shows that the activity of EPO-(CTP3 in TFI-1 cell proliferation assay is similar to that of EPO-WT and commercial rHEPO. However, in vivo studies indicated that treatment once a week with EPO-(CTP3 (15 μg/kg dramatically increased (~8 folds haematocrit as it was compared to rHuEPO. Moreover, it was found that EPO-(CTP3 is more effective than rHuEPO and Aranesp in increasing reticulocyte number in mice blood. The detected circulatory half-lives of rHuEPO, Aranesp, and EPO-(CTP3 following IV injection of 20 IU were 4.4, 10.8, and 13.1 h, respectively. These data established the rational for using this chimera as a long-acting EPO analog in clinics. The therapeutic efficacy of EPO-CTP analog needs to be established in higher animals and in human clinical trials.

Dynamic acetylation of all lysine 4-methylated histone H3 in the mouse nucleus: analysis at c-fos and c-jun.

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Catherine A Hazzalin

2005-12-01

Full Text Available A major focus of current research into gene induction relates to chromatin and nucleosomal regulation, especially the significance of multiple histone modifications such as phosphorylation, acetylation, and methylation during this process. We have discovered a novel physiological characteristic of all lysine 4 (K4-methylated histone H3 in the mouse nucleus, distinguishing it from lysine 9-methylated H3. K4-methylated histone H3 is subject to continuous dynamic turnover of acetylation, whereas lysine 9-methylated H3 is not. We have previously reported dynamic histone H3 phosphorylation and acetylation as a key characteristic of the inducible proto-oncogenes c-fos and c-jun. We show here that dynamically acetylated histone H3 at these genes is also K4-methylated. Although all three modifications are proven to co-exist on the same nucleosome at these genes, phosphorylation and acetylation appear transiently during gene induction, whereas K4 methylation remains detectable throughout this process. Finally, we address the functional significance of the turnover of histone acetylation on the process of gene induction. We find that inhibition of turnover, despite causing enhanced histone acetylation at these genes, produces immediate inhibition of gene induction. These data show that all K4-methylated histone H3 is subject to the continuous action of HATs and HDACs, and indicates that at c-fos and c-jun, contrary to the predominant model, turnover and not stably enhanced acetylation is relevant for efficient gene induction.

The influence of the N-terminal region of antimicrobial peptide pleurocidin on fungal apoptosis.

Science.gov (United States)

Choi, Hyemin; Lee, Dong Gun

2013-10-28

In our previous study, the 25-mer antimicrobial peptide pleurocidin (Ple) had been thought to induce apoptosis in Candida albicans. This study demonstrated that reactive oxygen species (ROS) production was a major cause of Ple-induced apoptosis. Four truncated analogs were synthesized to understand the functional roles in the N- and C-terminal regions of Ple on the apoptosis. Ple, Ple (4-25), Ple (1-22), and Ple (1-19) produced ROS, including hydroxyl radicals, on the order of [Ple > Ple (1-22) > Ple (4-25) > Ple (1-19)], whereas Ple (7-25) did not induce any ROS production. The results suggested that the N-terminal deletion affected the ROS-inducing activities much more than that of the C-terminal deletion, and net hydrophobicity [Ple > Ple (1-22) > Ple (4-25) > Ple (1-19) > Ple (7-25)] was related to ROS generation rather than other primary factors like net charge. Hence, we focused on the N-terminal-truncated peptides, Ple (4-25) and Ple (7-25), and examined other apoptotic features, including mitochondrial membrane depolarization, caspase activation, phosphatidylserine externalization, and DNA and nuclear fragmentation. The results also confirmed the disappearance of apoptotic activity of Ple (7-25) by the truncation of the N-terminal region (1-6) and the specific activity patterns between Ple and analogs. In conclusion, the N-terminal region of Ple played an important role in apoptosis.

DNA-Directed alkylating agents. 7. Synthesis, DNA interaction, and antitumor activity of bis(hydroxymethyl)- and bis(carbamate)-substituted pyrrolizines and imidazoles.

Science.gov (United States)

Atwell, G J; Fan, J Y; Tan, K; Denny, W A

1998-11-19

A series of bis(hydroxymethyl)-substituted imidazoles, thioimidazoles, and pyrrolizines and related bis(carbamates), linked to either 9-anilinoacridine (intercalating) or 4-(4-quinolinylamino)benzamide (minor groove binding) carriers, were synthesized and evaluated for sequence-specific DNA alkylation and cytotoxicity. The imidazole and thioimidazole analogues were prepared by initial synthesis of [(4-aminophenyl)alkyl]imidazole-, thioimidazole-, or pyrrolizine dicarboxylates, coupling of these with the desired carrier, and reduction to give the required bis(hydroxymethyl) alkylating moiety. The pyrrolizines were the most reactive alkylators, followed by the thioimidazoles, while the imidazoles were unreactive. The pyrrolizines and some of the thioimidazoles cross-linked DNA, as measured by agarose gel electrophoresis. Strand cleavage assays showed that none of the compounds reacted at purine N7 or N3 sites in the gpt region of the plasmid gpt2Eco, but the polymerase stop assay showed patterns of G-alkylation in C-rich regions. The corresponding thioimidazole bis(carbamates) were more selective than the bis(hydroxymethyl) pyrrolizines, with high-intensity bands at 5'-NCCN, 5'-NGCN and 5'-NCGN sequences in the PCR stopping assay ( indicates block sites). The data suggest that these targeted compounds, like the known thioimidazole bis(carbamate) carmethizole, alkylate exclusively at guanine residues via the 2-amino group, with little or no alkylation at N3 and N7 guanine or adenine sites. The cytotoxicities of the compounds correlated broadly with their reactivities, with the bis(hydroxymethyl)imidazoles being the least cytotoxic (IC50s >1 microM; P388 leukemia) and with the intercalator-linked analogues being more cytotoxic than the corresponding minor-groove-targeted ones. This was true also for the more reactive thioimidazole bis(carbamates) (IC50s 0.8 and 11 microM, respectively), but both were more active than the analogous "untargeted" carmethizole (IC50 20

Capacitaciones lúdicas en micro y pequeñas empresas del departamento de Junín

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Roberto De La Torre Santana

2015-06-01

Full Text Available Los objetivos fueron, proponer metodologías lúdicas vivenciales de capacitación para medir su valoración por los pequeños y microempresarios de la región Junín; y demostrar la posibilidad de atender a este segmento de mercado con capacitaciones especializadas en centros adecuados. El estudio fue de caracter descriptivo y para la recopilación de datos se utilizó la técnica de la encuesta, aplicado a 803 pequeños y microempresarios de ocho zonas de la región Junín para conocer su periodicidad de capacitación, percepción frente a ella y su grado de conocimiento sobre las capacitaciones lúdicas. Sobre esta muestra fue determinada otra muestra para la realización de cuatro talleres de capacitación lúdica vivencial, orientados a comprobar la hipótesis; asimismo se aplicó la metodología de laboratorio de negocios de la OIT en 58 empresarios durante enero y febrero de 2014. Los resultados indican que el 100 % de los empresarios participantes en los cuatro talleres consideraron que la capacitación lúdica es de alta aplicabilidad para sus negocios; el 96,6 % la consideraron activa y nada aburrida; y el 100 % también mostraron su disposición de participar en más de estas capacitaciones, incluso propusieron una lista de cursos o temas que demandarían. En conclusión, las capacitaciones lúdicas son muy bien recibidas y valoradas por el 96,6 % de los empresarios que participaron en los talleres. Este segmento es muy importante y numeroso, que bien orientado y con productos de capacitación a su medida, puede aprovechar al máximo el mercado de capacitación lúdica.

Use of green fluorescent protein fusions to analyse the N- and C-terminal signal peptides of GPI-anchored cell wall proteins in Candida albicans.

Science.gov (United States)

Mao, Yuxin; Zhang, Zimei; Wong, Brian

2003-12-01

Glycophosphatidylinositol (GPI)-anchored proteins account for 26-35% of the Candida albicans cell wall. To understand the signals that regulate these proteins' cell surface localization, green fluorescent protein (GFP) was fused to the N- and C-termini of the C. albicans cell wall proteins (CWPs) Hwp1p, Als3p and Rbt5p. C. albicans expressing all three fusion proteins were fluorescent at the cell surface. GFP was released from membrane fractions by PI-PLC and from cell walls by beta-glucanase, which implied that GFP was GPI-anchored to the plasma membrane and then covalently attached to cell wall glucans. Twenty and 25 amino acids, respectively, from the N- and C-termini of Hwp1p were sufficient to target GFP to the cell surface. C-terminal substitutions that are permitted by the omega rules (G613D, G613N, G613S, G613A, G615S) did not interfere with GFP localization, whereas some non-permitted substitutions (G613E, G613Q, G613R, G613T and G615Q) caused GFP to accumulate in intracellular ER-like structures and others (G615C, G613N/G615C and G613D/G615C) did not. These results imply that (i) GFP fusions can be used to analyse the N- and C-terminal signal peptides of GPI-anchored CWPs, (ii) the omega amino acid in Hwp1p is G613, and (iii) C can function at the omega+2 position in C. albicans GPI-anchored proteins.

Differential functions of C- and N-terminal hepatitis B x protein in liver cells treated with doxorubicin in normoxic or hypoxic condition.

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Davor Kin-Fan Chau

Full Text Available Hepatitis viral B x protein (HBx, a hepatocarcinogen, is frequently mutated. Hypoxia influences the growth of HCC and also the sensitivity of tumor cells to treatments. We aimed to test the role of HBx and acute hypoxia in the efficacy of chemotherapy. In this study, we established 4 Chang liver cell lines with the full-length HBx (HBx, the first 50 amino acids of N-terminal HBx (HBx/50, the last 104 amino acids of C-terminal HBx (HBx/51 and empty vector (CL, respectively. MTT and TNUEL assays were used to assess cell viability and apoptosis respectively. Western blot was used to determine the expression of relevant proteins. Results showed that among 4 cell lines, doxorubicin was most effective in decreasing the viability and enhancing apoptosis in HBx/51 cells, while HBx/50 cells were most resistant to the treatment. Cells in hypoxia were more susceptible to doxorubicin than cells in normoxia. Hypoxia facilitated the Bid cleavage especially in HBx/51 cells via phosphorylating p38 MAPK. p38 MAPK inhibitor significantly reduced the tBid level and increased cell viability. In conclusion, N-terminal HBx and C-terminal HBx function differentially in their ability to regulate cell growth, with the former being promotive but the latter being inhibitory. The acute hypoxia may overcome the HBx-induced resistance and facilitate the chemotherapy.

Planeamiento estratégico de las cajas municipales de ahorro y crédito de la Región Junín

OpenAIRE

Corilla Ruiz, Mariella; Julcarima Iñigo, Gilmar; Meneses Galindez, Carolina; Rodríguez Rivera, Franchesca

2017-01-01

La presente tesis desarrolla un planeamiento estratégico, con el propósito de que las Cajas Municipales de Ahorro y Crédito de la región Junín, se mantengan para el año 2022 como líderes del sector microfinanciero dentro de esta región, mediante la generación de soluciones financieras eficientes y eficaces basadas en incrementar la inclusión y educación financiera, la responsabilidad social y el cuidado del medio ambiente. Así mismo, el presente trabajo tiene por finalidad aume...

Influenza A H3N2 subtype virus NS1 protein targets into the nucleus and binds primarily via its C-terminal NLS2/NoLS to nucleolin and fibrillarin

Science.gov (United States)

2012-01-01

Background Influenza A virus non-structural protein 1 (NS1) is a virulence factor, which is targeted into the cell cytoplasm, nucleus and nucleolus. NS1 is a multi-functional protein that inhibits host cell pre-mRNA processing and counteracts host cell antiviral responses. Previously, we have shown that the NS1 protein of the H3N2 subtype influenza viruses possesses a C-terminal nuclear localization signal (NLS) that also functions as a nucleolar localization signal (NoLS) and targets the protein into the nucleolus. Results Here, we show that the NS1 protein of the human H3N2 virus subtype interacts in vitro primarily via its C-terminal NLS2/NoLS and to a minor extent via its N-terminal NLS1 with the nucleolar proteins, nucleolin and fibrillarin. Using chimeric green fluorescence protein (GFP)-NS1 fusion constructs, we show that the nucleolar retention of the NS1 protein is determined by its C-terminal NLS2/NoLS in vivo. Confocal laser microscopy analysis shows that the NS1 protein colocalizes with nucleolin in nucleoplasm and nucleolus and with B23 and fibrillarin in the nucleolus of influenza A/Udorn/72 virus-infected A549 cells. Since some viral proteins contain NoLSs, it is likely that viruses have evolved specific nucleolar functions. Conclusion NS1 protein of the human H3N2 virus interacts primarily via the C-terminal NLS2/NoLS and to a minor extent via the N-terminal NLS1 with the main nucleolar proteins, nucleolin, B23 and fibrillarin. PMID:22909121

Structural and spectral analyses of N,N'-(2,2'-dithiodi-o-phenylene)bis-(furan-2-carboxamide)

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Yıldırım, Sema Öztürk; Büyükmumcu, Zeki; Pekdur, Özlem Savaş; Butcher, Ray J.; Doǧan, Şengül Dilem

2018-02-01

In this study we report structure determination of N,N'-(2,2'-dithiodi-o-phenylene)bis-(furan-2-carboxamide). 2,2'-Dithiobis(benzamide) derivatives have been reported to possess important biological properties such as antibacterial, antifungal activities and inhibition of blood platelet aggregation and redeterrmined at 100(2)K from the data published by Raftery, Lallbeeharry, Bhowon, Laulloo & Joulea [Acta Cryst. 2009, E65, o16]. 2,2'-Dithiobis(N-butyl-benzamide) has been reported to be useful as an antiseptic for cosmetics. The structural properties of the compound have been characterized by using 1H NMR and the structure were determined by single-crystal X-ray diffraction. Molecular structure crystallizes in triclinic form, space group with a = 9.6396(7) Å, b = 9.9115(7) Å, c = 12.0026(8) Å, α = 109.743(6)°, β = 103.653(6)°, γ = 104.633(6)° and V = 977.15(13) Å3. In the solid state of the molecular structure N-H…S, N-H…O and C-H…O, type interactions provide for stabilization. The geometries of the title compound have been optimized using density functional theory (DFT) method. The calculated values were found to be in agreement with the experimental data.

The Synthesis of Backbone Thermo and pH Responsive Hyperbranched Poly(Bis(N,N-Propyl Acryl Amides by RAFT

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Shijiao Zhou

2016-04-01

Full Text Available Hyperbranched poly(methylene-bis-acrylamide, poly(bis(N,N-propyl acryl amide (HPNPAM and poly(bis(N,N-butyl acryl amide were synthesized by reversible addition-fragmentation chain transfer polymerization. HPNPAMs showed lower critical solution temperature (LCST due to an appropriate ratio between hydrophilic and hydrophobic groups. The effects of reaction conditions on polymerization were investigated in detail. The structure of HPNPAM was characterized by 1H NMR, FT-IR, Muti detector-size exclusion chromatography (MDSEC and Ultravioletvisble (UV-Vis. The α value reached 0.20 and DB was 90%, indicating HPNPAMs with compact topology structure were successfully prepared. LCSTs were tuned by Mw and the pH value of the solution. The change of molecular size was assayed by dynamic light scattering and scanning electron microscope. These results indicated that the stable uniform nanomicelles were destroyed and macromolecules aggregated together, forming large particles as temperature exceeded LCST. In addition, after the cells were incubated for 24 h, the cell viability reached 80%, which confirmed this new dual responsive HPNPAM had low cytotoxicity.

Presencia de Piscirickettsia salmonis en truchas de cultivo (Oncorhynchus mykiss) en Junín, Perú

OpenAIRE

Yunis A, Jefferson; Anicama D, Jahir; Manchego S, Alberto; Sandoval C, Nieves

2015-01-01

El objetivo de este estudio fue determinar la posible presencia de Piscirickettsia salmonis en truchas de cultivo (Oncorhynchus mykiss) en la cuenca del río Mantaro, Junín, Perú, mediante la prueba de inmunofluorescencia indirecta (IFI). Se obtuvieron 180 truchas en forma aleatoria de tres piscigranjas, se beneficiaron, se les realizó la necropsia y se recolectaron muestras de riñón y bazo. Los tejidos fueron sometidos a la prueba de inmunofluorescencia indirecta (IFI). Todas las muestras res...

Occurrence of C-Terminal Residue Exclusion in Peptide Fragmentation by ESI and MALDI Tandem Mass Spectrometry

Science.gov (United States)

Dupré, Mathieu; Cantel, Sonia; Martinez, Jean; Enjalbal, Christine

2012-02-01

the high mass range of the MS/MS spectra. The mass difference between this signal and the protonated molecular ion corresponds to the mass of the C-terminal residue. It allowed a straightforward identification of the amino acid positioned at this extremity. It must be emphasized that a neutral residue loss can be misattributed to the formation of a ym-1 ion, i.e., to the loss of the N-terminal residue following the a1-ym-1 fragmentation channel. Extreme caution must be adopted when reading the direct sequence ion on the positive ion MS/MS spectra of singly charged peptides not to mix up the attribution of the N- and C-terminal amino acids. Although such peculiar fragmentation behavior is of obvious interest for de novo peptide sequencing, it can also be exploited in proteomics, especially for studies involving digestion protocols carried out with proteolytic enzymes other than trypsin (Lys-N, Glu-C, and Asp-N) that produce arginine-containing peptides.

Laser processing for bevel termination of high voltage pn junction in SiC

International Nuclear Information System (INIS)

Kubiak, A; Ruta, Ł; Rosowski, A; French, P

2016-01-01

Proper edge termination of the p-n junction in silicon carbide is a key requirement in the fabrication of discrete devices able to withstand high voltages in reverse polarization. Due to the hardness of SiC the creation of the bevel termination remains difficult using mechanical machining. The use of laser beam sources with medium wavelength (532 nm) gives new possibilities in the machining of the silicon carbide. The paper presents the fabrication of the bevel termination structure in SiC using a green DPSS laser equipped with scanner and dedicated rotating sample holder. Characterization of the resulting structures proves the high potential of the proposed approach. (paper)

Identification of Molecular Receptors for Therapeutic Targeting in Prostate Cancer

Science.gov (United States)

2009-12-01

proteins linking integrin and tyrosine kinase receptors to the c-Jun N-terminal kinase /stress-activated protein kinase signaling pathway. J Biol Chem...of its SH domains. First, they contain important protein-protein interaction modules; and secondly they are non-catalytic regulators of kinase ...transcriptional reporter assay the SH2 , the N-terminal SH3 (SH3-N) and the C-terminal SH3 (SH3-C) domains of CRKL. We found that all three SH domains were

Hydroxyl Radical-Mediated Novel Modification of Peptides: N-Terminal Cyclization through the Formation of α-Ketoamide.

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Lee, Seon Hwa; Kyung, Hyunsook; Yokota, Ryo; Goto, Takaaki; Oe, Tomoyuki

2015-01-20

The hydroxyl radical-mediated oxidation of peptides and proteins constitutes a large group of post-translational modifications that can result in structural and functional changes. These oxidations can lead to hydroxylation, sulfoxidation, or carbonylation of certain amino acid residues and cleavage of peptide bonds. In addition, hydroxyl radicals can convert the N-terminus of peptides to an α-ketoamide via abstraction of the N-terminal α-hydrogen and hydrolysis of the ketimine intermediate. In the present study, we identified N-terminal cyclization as a novel modification mediated by a hydroxyl radical. The reaction of angiotensin (Ang) II (DRVYIHPF) and the hydroxyl radical generated by the Cu(II)/ascorbic acid (AA) system or UV/hydrogen peroxide system produced N-terminal cyclized-Ang II (Ang C) and pyruvamide-Ang II (Ang P, CH3COCONH-RVYIHPF). The structure of Ang C was confirmed by mass spectrometry and comparison to an authentic standard. The subsequent incubation of isolated Ang P in the presence of Cu(II)/AA revealed that Ang P was the direct precursor of Ang C. The proposed mechanism involves the formation of a nitrogen-centered (aminyl) radical, which cyclizes to form a five-membered ring containing the alkoxy radical. The subsequent β-scission reaction of the alkoxyl radical results in the cleavage of the terminal CH3CO group. The initial aminyl radical can be stabilized by chelation to the Cu(II) ions. The affinity of Ang C toward the Ang II type 1 receptor was significantly lower than that of Ang II or Ang P. Ang C was not further metabolized by aminopeptidase A, which converts Ang II to Ang III. Hydroxyl radical-mediated N-terminal cyclization was also observed in other Ang peptides containing N-terminal alanine, arginine, valine, and amyloid β 1-11 (DAEFRHDSGYE).

Expression and Purification of Z Protein from Junín Virus

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S. E. Goñi

2010-01-01

Full Text Available Arenaviridae comprises 23 recognized virus species with a bipartite ssRNA genome and an ambisense coding strategy. The virions are enveloped and include nonequimolar amounts of each genomic RNA species, designated L and S, coding for four ORFs (N, GPC, L, and Z. The arenavirus Junín (JUNV is the etiological agent of Argentine Hemorrhagic Fever, an acute disease with high mortality rate. It has been proposed that Z is the functional counterpart of the matrix proteins found in other negative-stranded enveloped RNA viruses. Here we report the optimized expression of a synthetic gene of Z protein, using three expression systems (two bacterial and a baculoviral one. One of these recombinant proteins was used to generate antibodies. A bioinformatic analysis was made where Z was subdivided into three domains. The data presented contributes methodologies for Z recombinant production and provides the basis for the development of new experiments to test its function.

N-doping of organic semiconductors by bis-metallosandwich compounds

Science.gov (United States)

Barlow, Stephen; Qi, Yabing; Kahn, Antoine; Marder, Seth; Kim, Sang Bok; Mohapatra, Swagat K.; Guo, Song

2016-01-05

The various inventions disclosed, described, and/or claimed herein relate to the field of methods for n-doping organic semiconductors with certain bis-metallosandwich compounds, the doped compositions produced, and the uses of the doped compositions in organic electronic devices. Metals can be manganese, rhenium, iron, ruthenium, osmium, rhodium, or iridium. Stable and efficient doping can be achieved.

N-terminal pro-C-type natriuretic peptide in serum associated with bone destruction in patients with multiple myeloma

DEFF Research Database (Denmark)

Mylin, Anne K; Goetze, Jens P; Heickendorff, Lene

2015-01-01

AIM: To examine whether N-terminal proCNP concentrations in serum is associated with bone destruction in patients with multiple myeloma. MATERIALS & METHODS: N-terminal proCNP and biochemical bone markers were measured in 153 patients. Radiographic bone disease and skeletal-related events were...

Bis{2-[(diisopropylphosphanylamino]pyridine-κ2N1,P}copper(I hexafluoridophosphate

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Özgür Öztopcu

2010-07-01

Full Text Available The crystal structure of the title compound, [Cu(C11H19N2P2]PF6, is composed of discrete [Cu(PN-iPr2]+ cations [PN-iPr is 2-(diisopropylphosphanylaminopyridine] and PF6− anions. The Cu(I atom is bis-chelated by two independent PN-iPr ligands. It has a distorted tetrahedral coordination by two P atoms [Cu—P = 2.2277 (4 and 2.2257 (4 Å] and two pyridine N atoms [Cu—N = 2.0763 (11 and 2.0845 (12 Å]. Bond angles about Cu vary from 85.11 (3 (P—Cu—N to 130.37 (2° (P—Cu—P. In the crystal, N—H...F hydrogen bonds link the Cu complexes and the PF6− anions into continuous chains, which show a cross-bedded spatial arrangement. In addition, several weaker C—H...F interactions contribute to the coherence of the structure.

Differential isotope dansylation labeling combined with liquid chromatography mass spectrometry for quantification of intact and N-terminal truncated proteins

International Nuclear Information System (INIS)

Tang, Yanan; Li, Liang

2013-01-01

Graphical abstract: -- Highlights: •LC–MS was developed for quantifying protein mixtures containing both intact and N-terminal truncated proteins. • 12 C 2 -Dansylation of the N-terminal amino acid of proteins was done first, followed by microwave-assisted acid hydrolysis. •The released 12 C 2 -dansyl labeled N-terminal amino acid was quantified using 13 C 2 -dansyl labeled amino acid standards. •The method provided accurate and precise results for quantifying intact and N-terminal truncated proteins within 8 h. -- Abstract: The N-terminal amino acids of proteins are important structure units for maintaining the biological function, localization, and interaction networks of proteins. Under different biological conditions, one or several N-terminal amino acids could be cleaved from an intact protein due to processes, such as proteolysis, resulting in the change of protein properties. Thus, the ability to quantify the N-terminal truncated forms of proteins is of great importance, particularly in the area of development and production of protein-based drugs where the relative quantity of the intact protein and its truncated form needs to be monitored. In this work, we describe a rapid method for absolute quantification of protein mixtures containing intact and N-terminal truncated proteins. This method is based on dansylation labeling of the N-terminal amino acids of proteins, followed by microwave-assisted acid hydrolysis of the proteins into amino acids. It is shown that dansyl labeled amino acids are stable in acidic conditions and can be quantified by liquid chromatography mass spectrometry (LC–MS) with the use of isotope analog standards

Structural and electrochemical studies of TiO2 complexes with (4,4'-((1E,1'E)-(2,5-bis(octyloxy)-1,4-phenylene)bis(ethene-2,1-diyl))bis-(E)-N-(2,5-bis(octyloxy)benzylidene)) imine derivative bases towards organic devices.

Science.gov (United States)

Rozycka, Anna; Iwan, Agnieszka; Bogdanowicz, Krzysztof Artur; Filapek, Michal; Górska, Natalia; Hreniak, Agnieszka; Marzec, Monika

2018-06-12

Three (4,4'-((1E,1'E)-(2,5-bis(octyloxy)-1,4-phenylene)bis(ethene-2,1-diyl))bis-(E)-N-(2,5-bis(octyloxy)benzylidene)) imine derivatives were synthesized via a condensation reaction with p-toluenesulfonic acid as a catalyst. The effects of the end groups and vinylene (-HC[double bond, length as m-dash]CH-) moieties on the structural, thermal, optical, electrochemical and photovoltaic properties of imines were investigated to check the influence of TiO2 on the imine properties. The thermal behavior of imines and their complexes with TiO2 was widely investigated using FT-IR, XRD, DSC and POM methods in order to determine the order type in the imine structure. All imines present the highest occupied molecular orbital (HOMO) levels of about -5.39 eV (SAI1 and SAI2) and -5.27 eV (SAI3) and the lowest unoccupied molecular orbital (LUMO) levels at about -3.17 eV. The difference of the end groups in the imines in each case did not affect redox properties. Generally, both oxidation and reduction are easier after TiO2 addition and it also changes the HOMO-LUMO levels of imines. Moreover, changes in the characteristic bands for imines in the region 1500-1700 cm-1 observed as a drastic decrease of intensity or even disappearance of bands in the imine : TiO2 mixture suggest the formation of a complex (C[double bond, length as m-dash]N)-TiO2. Organic devices with the configuration of ITO/TiO2/SAIx (or SAIx : TiO2)/Au were fabricated and investigated in the presence and absence of visible light irradiation with an intensity of 93 mW cm-2. In all imines and complexes with TiO2, the generation of the photocurrent indicates their use as photodiodes and the best result was observed for SAI3 : TiO2 complexes.

Crystal structure of N′′-benzyl-N′′-[3-(benzyldimethylazaniumylpropyl]-N,N,N′,N′-tetramethylguanidinium bis(tetraphenylborate

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Ioannis Tiritiris

2015-12-01

Full Text Available In the crystal structure of the title salt, C24H38N42+·2C24H20B−, the C—N bond lengths in the central CN3 unit of the guanidinium ion are 1.3364 (13, 1.3407 (13 and 1.3539 (13 Å, indicating partial double-bond character. The central C atom is bonded to the three N atoms in a nearly ideal trigonal–planar geometry and the positive charge is delocalized in the CN3 plane. The bonds between the N atoms and the terminal methyl groups of the guanidinium moiety and the four C—N bonds to the central N atom of the (benzyldimethylazaniumylpropyl group have single-bond character. In the crystal, C—H...π interactions between the guanidinium H atoms and the phenyl C atoms of the tetraphenylborate ions are present, leading to the formation of a two-dimensional supramolecular pattern parallel to the ac plane.

Dynamics of Fos-Jun-NFAT1 complexes.

Science.gov (United States)

Ramirez-Carrozzi, V R; Kerppola, T K

2001-04-24

Transcription initiation in eukaryotes is controlled by nucleoprotein complexes formed through cooperative interactions among multiple transcription regulatory proteins. These complexes may be assembled via stochastic collisions or defined pathways. We investigated the dynamics of Fos-Jun-NFAT1 complexes by using a multicolor fluorescence resonance energy transfer assay. Fos-Jun heterodimers can bind to AP-1 sites in two opposite orientations, only one of which is populated in mature Fos-Jun-NFAT1 complexes. We studied the reversal of Fos-Jun binding orientation in response to NFAT1 by measuring the efficiencies of energy transfer from donor fluorophores linked to opposite ends of an oligonucleotide to an acceptor fluorophore linked to one subunit of the heterodimer. The reorientation of Fos-Jun by NFAT1 was not inhibited by competitor oligonucleotides or heterodimers. The rate of Fos-Jun reorientation was faster than the rate of heterodimer dissociation at some binding sites. The facilitated reorientation of Fos-Jun heterodimers therefore can enhance the efficiency of Fos-Jun-NFAT1 complex formation. We also examined the influence of the preferred orientation of Fos-Jun binding on the stability and transcriptional activity of Fos-Jun-NFAT1 complexes. Complexes formed at sites where Fos-Jun favored the same binding orientation in the presence and absence of NFAT1 exhibited an 8-fold slower dissociation rate than complexes formed at sites where Fos-Jun favored the opposite binding orientation. Fos-Jun-NFAT1 complexes also exhibited greater transcription activation at promoter elements that favored the same orientation of Fos-Jun binding in the presence and absence of NFAT1. Thus, the orientation of heterodimer binding can influence both the dynamics and promoter selectivity of multiprotein transcription regulatory complexes.

La formación del mercado de tierras durante la expansión de la frontera bonaerense. Chascomús y Junín, 1860-1890

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Guillermo Banzato

2009-04-01

Full Text Available En este trabajo nos proponemos analizar la formación del mercado de tierras durante la expansión de la frontera de la provincia de Buenos Aires entre 1860 y 1890, a partir de un enfoque local comparado, enfocando la investigación en dos partidos: Chascomús y Junín. Postulamos que la constitución del mercado de tierras en la campaña bonaerense fue un proceso gradual, que se inició apenas comenzaron a poblarse las tierras defendidas por los fuertes de la frontera interior y se establecían ciertas garantías de seguridad para la propiedad privada

The N-terminal domain determines the affinity and specificity of H1 binding to chromatin

International Nuclear Information System (INIS)

Öberg, Christine; Belikov, Sergey

2012-01-01

Highlights: ► wt Human histone H1.4 and hH1.4 devoid of N-terminal domain, ΔN-hH1.4, were compared. ► Both histones bind to chromatin, however, ΔN-hH1.4 displays lower binding affinity. ► Interaction of ΔN-hH1.4 with chromatin includes a significant unspecific component. ► N-terminal domain is a determinant of specificity of histone H1 binding to chromatin. -- Abstract: Linker histone H1, one of the most abundant nuclear proteins in multicellular eukaryotes, is a key component of the chromatin structure mainly due to its role in the formation and maintenance of the 30 nm chromatin fiber. It has a three-domain structure; a central globular domain flanked by a short N-terminal domain and a long, highly basic C-terminal domain. Previous studies have shown that the binding abilities of H1 are at large determined by the properties of the C-terminal domain; much less attention has been paid to role of the N-terminal domain. We have previously shown that H1 can be reconstituted via cytoplasmic mRNA injection in Xenopus oocytes, cells that lack somatic H1. The heterologously expressed H1 proteins are incorporated into in vivo assembled chromatin at specific sites and the binding event is monitored as an increase in nucleosomal repeat length (NRL). Using this setup we have here compared the binding properties of wt-H1.4 and hH1.4 devoid of its N-terminal domain (ΔN-hH1.4). The ΔN-hH1.4 displays a drastically lower affinity for chromatin binding as compared to the wild type hH1.4. Our data also indicates that ΔN-hH1.4 is more prone to unspecific chromatin binding than the wild type. We conclude that the N-terminal domain of H1 is an important determinant of affinity and specificity of H1-chromatin interactions.

Activation of PI3K/Akt signaling by n-terminal SH2 domain mutants of the p85α regulatory subunit of PI3K is enhanced by deletion of its c-terminal SH2 domain.

Science.gov (United States)

Hofmann, Bianca T; Jücker, Manfred

2012-10-01

The phosphoinositide 3-kinase (PI3K) is frequently activated in human cancer cells due to gain of function mutations in the catalytic (p110) and the regulatory (p85) subunits. The regulatory subunit consists of an SH3 domain and two SH2 domains. An oncogenic form of p85α named p65 lacking the c-terminal SH2 domain (cSH2) has been cloned from an irradiation-induced murine thymic lymphoma and transgenic mice expressing p65 in T lymphocytes develop a lymphoproliferative disorder. We have recently detected a c-terminal truncated form of p85α named p76α in a human lymphoma cell line lacking most of the cSH2 domain due to a frame shift mutation. Here, we report that the deletion of the cSH2 domain enhances the activating effects of the n-terminal SH2 domain (nSH2) mutants K379E and R340E on the PI3K/Akt pathway and micro tumor formation in a focus assay. Further analysis revealed that this transforming effect is mediated by activation of the catalytic PI3K isoform p110α and downstream signaling through mTOR. Our data further support a mechanistic model in which mutations of the cSH2 domain of p85α can abrogate its negative regulatory function on PI3K activity via the nSH2 domain of p85α. Copyright © 2012 Elsevier Inc. All rights reserved.

C0 and C1 N-terminal Ig domains of myosin binding protein C exert different effects on thin filament activation.

Science.gov (United States)

Harris, Samantha P; Belknap, Betty; Van Sciver, Robert E; White, Howard D; Galkin, Vitold E

2016-02-09

Mutations in genes encoding myosin, the molecular motor that powers cardiac muscle contraction, and its accessory protein, cardiac myosin binding protein C (cMyBP-C), are the two most common causes of hypertrophic cardiomyopathy (HCM). Recent studies established that the N-terminal domains (NTDs) of cMyBP-C (e.g., C0, C1, M, and C2) can bind to and activate or inhibit the thin filament (TF). However, the molecular mechanism(s) by which NTDs modulate interaction of myosin with the TF remains unknown and the contribution of each individual NTD to TF activation/inhibition is unclear. Here we used an integrated structure-function approach using cryoelectron microscopy, biochemical kinetics, and force measurements to reveal how the first two Ig-like domains of cMyPB-C (C0 and C1) interact with the TF. Results demonstrate that despite being structural homologs, C0 and C1 exhibit different patterns of binding on the surface of F-actin. Importantly, C1 but not C0 binds in a position to activate the TF by shifting tropomyosin (Tm) to the "open" structural state. We further show that C1 directly interacts with Tm and traps Tm in the open position on the surface of F-actin. Both C0 and C1 compete with myosin subfragment 1 for binding to F-actin and effectively inhibit actomyosin interactions when present at high ratios of NTDs to F-actin. Finally, we show that in contracting sarcomeres, the activating effect of C1 is apparent only once low levels of Ca(2+) have been achieved. We suggest that Ca(2+) modulates the interaction of cMyBP-C with the TF in the sarcomere.

Cardiovascular risk prediction by N-terminal pro brain natriuretic peptide and high sensitivity C-reactive protein is affected by age and sex

DEFF Research Database (Denmark)

Olsen, M.H.; Hansen, T.W.; Christensen, M.K.

2008-01-01

BACKGROUND: Previous studies have shown that the urine albumin/creatinine ratio (UACR), high sensitivity C-reactive protein (hsCRP) and N-terminal pro brain natriuretic peptide (Nt-proBNP) predict cardiovascular events in a general population aged 41, 51, 61 or 71 years. This study investigated...

EL CRITERIO DE INTERPRETACIÓN DEL PRINCIPIO NON BIS IN ÍDEM PREVISTO EN EL ARTÍCULO 45.3 DE LA CONSTITUCIÓN ESPAÑOLA The Interpretation Criterium of the "Non Bis Idem" Principle Provided in Article 45.3 of Spain Constitution

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Ramírez Torrado María Lourdes

2010-01-01

Full Text Available Respecto a la lectura constitucional del principio se propone una interpretación complementaria y diversa a la hasta ahora presentada por la doctrina constitucional y científica que insisten en derivar el sustento constitucional del postulado non bis in ídem del artículo 25. Desconociendo lo anterior, una disposición constitucional que prevé tácitamente el non bis in ídem al establecer un criterio para determinar cuál es la sanción o el procedimiento a imponer sin quebrantar la prohibición bis in ídem.Con ello nos referimos a la presencia de un cláusula de interpretación del principio non bis in ídem, prevista en el artículo 45.3, que contempla en su texto la prevalencia del Derecho Penal sobre el Administrativo.With respect to the constitutional reading of the principle we propose a complementary and diverse reading different from what has been presented to date by constitutional and scientific doctrine, which insist on deriving constitutional support from article 25.Setting the former aside, there is a constitutional disposition which considers tacitly the "non bis in idem" by establishing a criterion to determine what the sanction or the procedure is to be imposed without violating prohibition "bis in idem". We refer to the presence of an interpretation clause of the "bis in idem" principle provided in article 45.3, which considers the prevalence of Penal Law over Administrative Law.

Organomolybdenum (VI) and lithium Organomolybdate (VI) and (V) Complexes with C,N-Chelating Aminoaryl Ligands

NARCIS (Netherlands)

Koten, G. van; Brandts, J.A.M.; Leur, M. de; Gossage, R.A.; Spek, A.L.

1999-01-01

The synthesis and characterization of new, five-coordinate molybdenum bis(imidoaryl) complexes [Mo(NAr)2(C-N)X] (Ar = C6H3i-Pr2-2,6; C-N = [C6H4(CH2NMe2)-2]-; X = Cl (1), Me (2), Et (3), Bu (4), CH2SiMe3 (5), (p-tolyl) (6), (C-N) (7)) is reported. The solid-state structure of 2 has been elucidated

Differential isotope dansylation labeling combined with liquid chromatography mass spectrometry for quantification of intact and N-terminal truncated proteins

Energy Technology Data Exchange (ETDEWEB)

Tang, Yanan; Li, Liang, E-mail: Liang.Li@ualberta.ca

2013-08-20

Graphical abstract: -- Highlights: •LC–MS was developed for quantifying protein mixtures containing both intact and N-terminal truncated proteins. •{sup 12}C{sub 2}-Dansylation of the N-terminal amino acid of proteins was done first, followed by microwave-assisted acid hydrolysis. •The released {sup 12}C{sub 2}-dansyl labeled N-terminal amino acid was quantified using {sup 13}C{sub 2}-dansyl labeled amino acid standards. •The method provided accurate and precise results for quantifying intact and N-terminal truncated proteins within 8 h. -- Abstract: The N-terminal amino acids of proteins are important structure units for maintaining the biological function, localization, and interaction networks of proteins. Under different biological conditions, one or several N-terminal amino acids could be cleaved from an intact protein due to processes, such as proteolysis, resulting in the change of protein properties. Thus, the ability to quantify the N-terminal truncated forms of proteins is of great importance, particularly in the area of development and production of protein-based drugs where the relative quantity of the intact protein and its truncated form needs to be monitored. In this work, we describe a rapid method for absolute quantification of protein mixtures containing intact and N-terminal truncated proteins. This method is based on dansylation labeling of the N-terminal amino acids of proteins, followed by microwave-assisted acid hydrolysis of the proteins into amino acids. It is shown that dansyl labeled amino acids are stable in acidic conditions and can be quantified by liquid chromatography mass spectrometry (LC–MS) with the use of isotope analog standards.

Valoración económica del almacenamiento de agua y carbono en la comunidad campesina Villa de Junín

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Miguel Vila Balbin

2015-12-01

Full Text Available El objetivo ha sido estimar el valor económico que generan los bofedales en el almacenamiento de agua y carbono en la comunidad campesina Villa de Junín en el departamento de Junín, Perú. El proceso de recolección de datos a estado enfocado en datos meteorológicos (temperatura y precipitación, datos de la actividad económica predominante (ganadería, recolección de muestras de suelo para hallar el contenido de carbono y capacidad volumétrica; posteriormente se hizo la comparación del beneficio percibido por la actividad ganadera y el beneficio que se podría obtener por los servicios que brinda un bofedal (almacenamiento de agua y carbono. Entre los resultados respecto a la precipitación anual se ha determinado 22 367 664 m3/año, del cual un 42,56 % (9 294 933,67 m3/ año regresa a la atmósfera a través del proceso de la evapotranspiración, quedando una oferta hídrica disponible de 13 072 730,33 m3/año, que representa un 57,44 % de la oferta hídrica total; la productividad hídrica es de 0,01 S/./m3. El costo de oportunidad que tiene la ganadería es de 200,38 S/./ha /año; el valor económico de agua y carbono es de S/. 48 974 181,79 y S/. 44 305 010,31 respectivamente. Se concluye que el almacenamiento de agua y carbono brindan mayores ingresos económicos a la población que la actividad ganadera.

Crystal structure, solvothermal synthesis, thermogravimetric studies and DFT calculations of a five-coordinate cobalt(II) compound based on the N,N-bis-(2-hy-droxy-eth-yl)glycine anion.

Science.gov (United States)

Zhou, Yanling; Liu, Xianrong; Wang, Qijun; Wang, Lisheng; Song, Baoling

2016-10-01

The reaction of CoCl 2 ·6H 2 O, N , N -bis-(2-hy-droxy-eth-yl)glycine and tri-ethyl-amine (Et 3 N) in ethanol solution under solvothermal conditions produced crystals of [ N , N -bis-(2-hy-droxy-eth-yl)glycinato]chloridocobalt(II), [Co(C 6 H 12 NO 4 )Cl]. The Co II ion is coordinated in a slightly distorted trigonal-bipyramidal environment which is defined by three O atoms occupying the equatorial plane and the N and Cl atoms in the apical sites. In the crystal, two types of O-H⋯O hydrogen bonds connect the mol-ecules, forming a two-dimensional network parallel to (001). The mol-ecular structure of the title compound confirms the findings of FTIR, elemental analysis, ESI-MS analysis and TG analysis. By using the density functional theory (DFT) (B3LYP) method with 6-31G(d) basis set, the molecular structure has been calculated and optimized.

Changes in Cytokines and Aggrecan ARGS Neoepitope in Synovial Fluid and Serum and in C-Terminal Crosslinking Telopeptide of Type II Collagen and N-Terminal Crosslinking Telopeptide of Type I Collagen in Urine Over Five Years After Anterior Cruciate Ligament Rupture

DEFF Research Database (Denmark)

Struglics, André; Larsson, Staffan; Kumahashi, Nobuyuki

2015-01-01

OBJECTIVE: To prospectively monitor levels of proinflammatory cytokines and aggrecan ARGS neoepitope in synovial fluid and serum as well as levels of C-terminal crosslinking telopeptide of type II collagen (CTX-II) and N-terminal crosslinking telopeptide of type I collagen (NTX-I) in urine after ...

Bis-ligated Ti and Zr complexes of chelating N-heterocyclic carbenes

KAUST Repository

El-Batta, Amer; Waltman, Andrew W.; Grubbs, Robert H.

2011-01-01

In this communication we report the synthesis of novel titanium and zirconium complexes ligated by bidentate "salicylaldimine-like" N-heterocyclic carbenes (NHC). Double addition of the NHC chelate to either TiCl4(thf)2 or ZrCl4 forms bis

Kinetic Investigation of the Electrochemical Oxidation of Bis(benzene)chromium(0) in Diethyl ketone / N,N-Dimethylformamide

Czech Academy of Sciences Publication Activity Database

Tsierkezos, Nikos

2008-01-01

Roč. 37, č. 10 (2008), s. 1437-1448 ISSN 0095-9782 Institutional research plan: CEZ:AV0Z40550506 Keywords : bis(benzene)chromium(0) * cyclic voltammetry * diethyl ketone * half-wawe potential * N,N-dimethylformamide Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.241, year: 2008

Living between multiple sites: transnational family relations from the perspective of elderly non-migrants in Junín, Peru

NARCIS (Netherlands)

de Bruine, E.; Hordijk, M.; Tamagno, C.; Sánchez Arimborgo, Y.

2013-01-01

Transnationality—defined as maintaining a sense of familyhood across national borders—is a complex process. This article studies the complexities of transnationality by analysing remittance-sending and practices of connectivity between migrants and non-migrants from the Junín region in Peru, in

Tetrakis[bis(pyridin-2-ylamine-κN2](nitrato-κOsilver(I

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Yuliia Parashchenko

2014-02-01

Full Text Available In the title complex, [Ag(NO3(C10H9N34], the nitrate ligand is found to be disordered over two sets of positions, with occupancy factors of 0.473 (5 and 0.527 (5. The AgI ion is located in a square-pyramidal coordination environment formed by four N atoms from four bis(pyridin-2-ylamine ligands and one O atom from a nitrate ligand. Weak interactions between the AgI ions and the nitrate anions acting in a monodentate mode [Ag...O = 2.791 (13 and 2.816 (9 Å for the major component of the nitrate ligand, and 2.865 (8 and 2.837 (8 Å for the minor component] link the complex molecules into a chain along [001]. N—H...O hydrogen bonds are observed.

Antiepileptic Effect of Uncaria rhynchophylla and Rhynchophylline Involved in the Initiation of c-Jun N-Terminal Kinase Phosphorylation of MAPK Signal Pathways in Acute Seizures of Kainic Acid-Treated Rats

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Hsin-Cheng Hsu

2013-01-01

Full Text Available Seizures cause inflammation of the central nervous system. The extent of the inflammation is related to the severity and recurrence of the seizures. Cell surface receptors are stimulated by stimulators such as kainic acid (KA, which causes intracellular mitogen-activated protein kinase (MAPK signal pathway transmission to coordinate a response. It is known that Uncaria rhynchophylla (UR and rhynchophylline (RP have anticonvulsive effects, although the mechanisms remain unclear. Therefore, the purpose of this study is to develop a novel strategy for treating epilepsy by investigating how UR and RP initiate their anticonvulsive mechanisms. Sprague-Dawley rats were administered KA (12 mg/kg, i.p. to induce seizure before being sacrificed. The brain was removed 3 h after KA administration. The results indicate that pretreatment with UR (1.0 g/kg, RP (0.25 mg/kg, and valproic acid (VA, 250 mg/kg for 3 d could reduce epileptic seizures and could also reduce the expression of c-Jun aminoterminal kinase phosphorylation (JNKp of MAPK signal pathways in the cerebral cortex and hippocampus brain tissues. Proinflammatory cytokines interleukin (IL-1β, IL-6, and tumor necrosis factor-α remain unchanged, indicating that the anticonvulsive effect of UR and RP is initially involved in the JNKp MAPK signal pathway during the KA-induced acute seizure period.

Antiepileptic Effect of Uncaria rhynchophylla and Rhynchophylline Involved in the Initiation of c-Jun N-Terminal Kinase Phosphorylation of MAPK Signal Pathways in Acute Seizures of Kainic Acid-Treated Rats.

Science.gov (United States)

Hsu, Hsin-Cheng; Tang, Nou-Ying; Liu, Chung-Hsiang; Hsieh, Ching-Liang

2013-01-01

Seizures cause inflammation of the central nervous system. The extent of the inflammation is related to the severity and recurrence of the seizures. Cell surface receptors are stimulated by stimulators such as kainic acid (KA), which causes intracellular mitogen-activated protein kinase (MAPK) signal pathway transmission to coordinate a response. It is known that Uncaria rhynchophylla (UR) and rhynchophylline (RP) have anticonvulsive effects, although the mechanisms remain unclear. Therefore, the purpose of this study is to develop a novel strategy for treating epilepsy by investigating how UR and RP initiate their anticonvulsive mechanisms. Sprague-Dawley rats were administered KA (12 mg/kg, i.p.) to induce seizure before being sacrificed. The brain was removed 3 h after KA administration. The results indicate that pretreatment with UR (1.0 g/kg), RP (0.25 mg/kg), and valproic acid (VA, 250 mg/kg) for 3 d could reduce epileptic seizures and could also reduce the expression of c-Jun aminoterminal kinase phosphorylation (JNKp) of MAPK signal pathways in the cerebral cortex and hippocampus brain tissues. Proinflammatory cytokines interleukin (IL)-1 β , IL-6, and tumor necrosis factor- α remain unchanged, indicating that the anticonvulsive effect of UR and RP is initially involved in the JNKp MAPK signal pathway during the KA-induced acute seizure period.

Bis[tris(1H-pyrazol-1-yl-κN2methane]nickel(II bis{[tris(1H-pyrazol-1-yl-κN2methane]tris(thiocyanato-κNnickelate(II} methanol disolvate

Directory of Open Access Journals (Sweden)

Ganna Lyubartseva

2011-12-01

Full Text Available Attempts to prepare the mononuclear [(tpmNiIIL3]−1 [tpm = tris(1H-pyrazol-1-ylmethane and L = thiocyanate] anion yielded the methanol-solvated salt, [(tpm2NiII][(tpmNiII(NCS3]2·2CH3OH or [Ni(C10H10N62][Ni(NCS3(C10H10N6]2·2CH3OH. The asymmetric unit consists of half a centrosymmetric bis[tris(1H-pyrazol-1-ylmethane]nickel(II cation and an octahedral nickelate(II anion bound to one tpm and three L ligands, and a methanol solvent molecule. One of the L ligands is disordered over two positions with occupancy factors of 0.650 (3 and 0.350 (3. There are O—H...S interactions between the methanol and the disordered thiocyanate anion, and a weak C—H...O hydrogen bond between the cation and the methanol O atom.

Hexaaquabis[3,5-bis(hydroxyimino-1-methyl-2,4,6-trioxocyclohexanido-κ2N3,O4]barium tetrahydrate

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Nguyen Dinh Do

2013-11-01

Full Text Available In the title compound, [Ba(C7H5N2O52(H2O6]·4H2O, the Ba2+ cation lies on a twofold rotation axis and is ten-coordinated by two 3,5-bis(hydroxyimino-1-methyl-2,4,6-trioxocyclohexanide oxo O atoms [Ba—O = 2.8715 (17 Å], two hydroxyimino N atoms [Ba—N = 3.036 (2 Å], and six water molecules [Ba—O = 2.847 (2, 2.848 (2, and 2.880 (2 Å]. The 3,5-bis(hydroxyimino-1-methyl-2,4,6-trioxocyclohexanide monoanions act in a bidentate chelating manner, coordinating through an N atom of the non-deprotonated hydroxyimino group and an O atom of the neighboring oxo group. Two lattice water molecules are located in the cavities of the framework and are involved in hydrogen bonding to O atoms of one of the coordinating water molecules and the O atom of a keto group of the ligand. As a result, a three-dimensional network is formed.

New OprM structure highlighting the nature of the N-terminal anchor

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Laura eMONLEZUN

2015-07-01

Full Text Available Among the different mechanisms used by bacteria to resist antibiotics, active efflux plays a major role. In gram-negative bacteria, active efflux is carried out by tripartite efflux pumps that form a macromolecular assembly spanning both membranes of the cellular wall. At the outer membrane level, a well-conserved Outer Membrane Factor (OMF protein acts as an exit duct, but its sequence varies greatly among different species. The OMFs share a similar tri-dimensional structure that includes a beta-barrel pore domain that stabilizes the channel within the membrane. In addition, OMFs are often subjected to different N-terminal post-translational modifications, such as an acylation with a lipid. The role of additional N-terminal anchors is all the more intriguing since it is not always required among the OMFs family. Understanding this optional post-translational modification could open new research lines in the field of antibiotics resistance. In E. coli, it has been shown that CusC is modified with a tri-acylated lipid, whereas TolC does not show any. In the case of OprM from Pseudomonas aeruginosa, the N-terminal modification remains a matter of debate, therefore, we used several approaches to investigate this issue. As definitive evidence, we present a new X ray structure at 3.8Å resolution that was solved in a new space group, making it possible to model the N-terminal residue as a palmitylated cysteine.

An intermediate region in C-terminal of phosphoprotein is required ...

African Journals Online (AJOL)

In this study, the region of P that binds to NPNC was mapped. To determine the binding region, 18 N- and C-terminally truncated P mutants were synthesized by in vitro translation in rabbit reticulocytes and mixed with purified NP (NPNC). The mutants which did not bind to NP were considered as mutants and they contain ...

N-terminal nesprin-2 variants regulate β-catenin signalling

Energy Technology Data Exchange (ETDEWEB)

Zhang, Qiuping; Minaisah, Rose-Marie; Ferraro, Elisa; Li, Chen; Porter, Lauren J.; Zhou, Can; Gao, Fang; Zhang, Junyi; Rajgor, Dipen; Autore, Flavia; Shanahan, Catherine M.; Warren, Derek T., E-mail: derek.warren@kcl.ac.uk

2016-07-15

The spatial compartmentalisation of biochemical signalling pathways is essential for cell function. Nesprins are a multi-isomeric family of proteins that have emerged as signalling scaffolds, herein, we investigate the localisation and function of novel nesprin-2 N-terminal variants. We show that these nesprin-2 variants display cell specific distribution and reside in both the cytoplasm and nucleus. Immunofluorescence microscopy revealed that nesprin-2 N-terminal variants colocalised with β-catenin at cell-cell junctions in U2OS cells. Calcium switch assays demonstrated that nesprin-2 and β-catenin are lost from cell-cell junctions in low calcium conditions whereas emerin localisation at the NE remained unaltered, furthermore, an N-terminal fragment of nesprin-2 was sufficient for cell-cell junction localisation and interacted with β-catenin. Disruption of these N-terminal nesprin-2 variants, using siRNA depletion resulted in loss of β-catenin from cell-cell junctions, nuclear accumulation of active β-catenin and augmented β-catenin transcriptional activity. Importantly, we show that U2OS cells lack nesprin-2 giant, suggesting that the N-terminal nesprin-2 variants regulate β-catenin signalling independently of the NE. Together, these data identify N-terminal nesprin-2 variants as novel regulators of β-catenin signalling that tether β-catenin to cell-cell contacts to inhibit β-catenin transcriptional activity. - Highlights: • N-terminal nesprin-2 variants display cell specific expression patterns. • N-terminal spectrin repeats of nesprin-2 interact with β-catenin. • N-terminal nesprin-2 variants scaffold β-catenin at cell-cell junctions.. • Nesprin-2 variants play multiple roles in β-catenin signalling.

Synthesis of Acridine-based DNA Bis-intercalating Agents

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P. Mack

2001-02-01

Full Text Available Methods for the synthesis of N1, N8-bis(9-acridinyl-N4-(4-hydroxybenzyl-spermidine and N1, N7-(hydroxybenzyl-bis-(3-aminopropylamine were investigated. Thus monocyanoethylation of 4-methoxybenzylamine followed by treatment with 4-chlorobutyronitrile gave the dinitrile N-(2-cyanoethyl-N-(3-cyanopropyl-4-methoxybenzylamine. Subsequent in situ reduction with lithium aluminium hydride gave the corresponding diamine. Biscyanoethylation of 4-methoxybenzylamine with 2 mole of acrylonitrile followed by reduction yielded the diamine N, N-bis-(3-aminopropyl-4-methoxybenzylamine. Both diamines reacted smoothly with 9-methoxyacridine to give the bis-(9-acridinyl compounds 11 and 15 but with 4,5-dimethyl-9-methoxyacridine, the bis compound 16 was produced in only low yields. Demethylation of the dinitriles by a variety of approaches all failed to give the corresponding hydroxybenzyl derivatives. These studies yielded useful methylated tyrosine derivatives which could also be iodinated. This study has been useful for elucidating chemical methods needed for the synthesis of the desired tyrosine-based bis acridine compound and for alerting us to the need to synthesise a more labile protected tyrosine intermediate which will be easily deprotected to afford the desired tyrosine-based bis acridine compound.

Upregulation of α7 Nicotinic Receptors by Acetylcholinesterase C-Terminal Peptides

Science.gov (United States)

Bond, Cherie E.; Zimmermann, Martina; Greenfield, Susan A.

2009-01-01

Background The alpha-7 nicotinic acetylcholine receptor (α7-nAChR) is well known as a potent calcium ionophore that, in the brain, has been implicated in excitotoxicity and hence in the underlying mechanisms of neurodegenerative disorders such as Alzheimer's disease. Previous research implied that the activity of this receptor may be modified by exposure to a peptide fragment derived from the C-terminal region of the enzyme acetylcholinesterase. This investigation was undertaken to determine if the functional changes observed could be attributed to peptide binding interaction with the α7-nAChR, or peptide modulation of receptor expression. Methodology/Principal Findings This study provides evidence that two peptides derived from the C-terminus of acetylcholinesterase, not only selectively displace specific bungarotoxin binding at the α7-nAChR, but also alter receptor binding properties for its familiar ligands, including the alternative endogenous agonist choline. Of more long-term significance, these peptides also induce upregulation of α7-nAChR mRNA and protein expression, as well as enhancing receptor trafficking to the plasma membrane. Conclusions/Significance The results reported here demonstrate a hitherto unknown relationship between the α7-nAChR and the non-enzymatic functions of acetylcholinesterase, mediated independently by its C-terminal domain. Such an interaction may prove valuable as a pharmacological tool, prompting new approaches for understanding, and combating, the process of neurodegeneration. PMID:19287501

Synthesis, characterization, and reactivity of furan- and thiophene-functionalized bis(n-heterocyclic carbene) complexes of iron(II)

KAUST Repository

Rieb, Julia

2014-09-15

The synthesis of iron(II) complexes bearing new heteroatom-functionalized methylene-bridged bis(N-heterocyclic carbene) ligands is reported. All complexes are characterized by single-crystal X-ray diffraction (SC-XRD), nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis. Tetrakis(acetonitrile)-cis-[bis(o-imidazol-2-ylidenefuran)methane]iron(II) hexafluorophosphate (2a) and tetrakis(acetonitrile)-cis-[bis(o-imidazol-2-ylidenethiophene)methane]iron(II) hexafluorophosphate (2b) were obtained by aminolysis of [Fe{N(SiMe3)2}2(THF)] with furan- and thiophene-functionalized bis(imidazolium) salts 1a and 1b in acetonitrile. The SC-XRD structures of 2a and 2b show coordination of the bis(carbene) ligand in a bidentate fashion instead of a possible tetradentate coordination. The four other coordination sites of these distorted octahedral complexes are occupied by acetonitrile ligands. Crystallization of 2a in an acetone solution by the slow diffusion of Et2O led to the formation of cisdiacetonitriledi[ bis(o-imidazol-2-ylidenefuran)methane]iron(II) hexafluorophosphate (3a) with two bis(carbene) ligands coordinated in a bidentate manner and two cis-positioned acetonitrile molecules. Compounds 2a and 2b are the first reported iron(II) carbene complexes with four coordination sites occupied by solvent molecules, and it was demonstrated that those solvent ligands can undergo ligand-exchange reactions.

Bis(μ-bis{[4-(2-pyridylpyrimidin-2-yl]sulfanyl}methanedisilver(I bis(perchlorate

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Hai-Bin Zhu

2010-12-01

Full Text Available In the macrocyclic centrosymmetric dinuclear complex, [Ag2(C19H14N6S22](ClO42, the AgI atom, bis{[4-(2-pyridylpyrimidin-2-yl]sulfanyl}methane (2-bppt ligand and perchlorate anion each lie on a twofold rotation axis. The 2-bppt ligand chelates two four-coordinated AgI atoms through its two bipyridine-like arms. The O atoms of the perchlorate anion are disordered each over two positions of equal occupancy. Adjacent complex molecules are linked by π–π interactions between the pyridine and pyrimidine rings [centroid–centroid distance = 3.663 (8 Å].

Bipodal surface organometallic complexes with surface N-donor ligands and application to the catalytic cleavage of C-H and C-C bonds in n -Butane

KAUST Repository

Bendjeriou-Sedjerari, Anissa

2013-11-27

We present a new generation of "true vicinal" functions well-distributed on the inner surface of SBA15: [(Sî - Si-NH 2)(≡Si-OH)] (1) and [(≡Si-NH2)2] (2). From these amine-modified SBA15s, two new well-defined surface organometallic species [(≡Si-NH-)(≡Si-O-)]Zr(CH2tBu) 2 (3) and [(≡Si-NH-)2]Zr(CH2tBu) 2 (4) have been obtained by reaction with Zr(CH2tBu) 4. The surfaces were characterized with 2D multiple-quantum 1H-1H NMR and infrared spectroscopies. Energy-filtered transmission electron microscopy (EFTEM), mass balance, and elemental analysis unambiguously proved that Zr(CH2tBu)4 reacts with these vicinal amine-modified surfaces to give mainly bipodal bis(neopentyl)zirconium complexes (3) and (4), uniformly distributed in the channels of SBA15. (3) and (4) react with hydrogen to give the homologous hydrides (5) and (6). Hydrogenolysis of n-butane catalyzed by these hydrides was carried out at low temperature (100 C) and low pressure (1 atm). While (6) exhibits a bis(silylamido)zirconium bishydride, [(≡Si-NH-)2]Zr(H) 2 (6a) (60%), and a bis(silylamido)silyloxozirconium monohydride, [(≡Si-NH-)2(≡Si-O-)]ZrH (6b) (40%), (5) displays a new surface organometallic complex characterized by an 1H NMR signal at 14.46 ppm. The latter is assigned to a (silylimido)(silyloxo)zirconium monohydride, [(≡Si-Nî)(≡Si-O-)]ZrH (5b) (30%), coexistent with a (silylamido)(silyloxo)zirconium bishydride, [(≡Si-NH-)(≡Si-O-)] Zr(H)2 (5a) (45%), and a silylamidobis(silyloxo)zirconium monohydride, [(≡Si-NH-)(≡Si-O-)2]ZrH (5c) (25%). Surprisingly, nitrogen surface ligands possess catalytic properties already encountered with silicon oxide surfaces, but interestingly, catalyst (5) with chelating [N,O] shows better activity than (6) with chelating [N,N]. © 2013 American Chemical Society.

Bipodal surface organometallic complexes with surface N-donor ligands and application to the catalytic cleavage of C-H and C-C bonds in n -Butane

KAUST Repository

Bendjeriou-Sedjerari, Anissa; Azzi, Joachim; Abou-Hamad, Edy; Anjum, Dalaver H.; Pasha, Fahran A.; Huang, Kuo-Wei; Emsley, Lyndon; Basset, Jean-Marie

2013-01-01

We present a new generation of "true vicinal" functions well-distributed on the inner surface of SBA15: [(Sî - Si-NH 2)(≡Si-OH)] (1) and [(≡Si-NH2)2] (2). From these amine-modified SBA15s, two new well-defined surface organometallic species [(≡Si-NH-)(≡Si-O-)]Zr(CH2tBu) 2 (3) and [(≡Si-NH-)2]Zr(CH2tBu) 2 (4) have been obtained by reaction with Zr(CH2tBu) 4. The surfaces were characterized with 2D multiple-quantum 1H-1H NMR and infrared spectroscopies. Energy-filtered transmission electron microscopy (EFTEM), mass balance, and elemental analysis unambiguously proved that Zr(CH2tBu)4 reacts with these vicinal amine-modified surfaces to give mainly bipodal bis(neopentyl)zirconium complexes (3) and (4), uniformly distributed in the channels of SBA15. (3) and (4) react with hydrogen to give the homologous hydrides (5) and (6). Hydrogenolysis of n-butane catalyzed by these hydrides was carried out at low temperature (100 C) and low pressure (1 atm). While (6) exhibits a bis(silylamido)zirconium bishydride, [(≡Si-NH-)2]Zr(H) 2 (6a) (60%), and a bis(silylamido)silyloxozirconium monohydride, [(≡Si-NH-)2(≡Si-O-)]ZrH (6b) (40%), (5) displays a new surface organometallic complex characterized by an 1H NMR signal at 14.46 ppm. The latter is assigned to a (silylimido)(silyloxo)zirconium monohydride, [(≡Si-Nî)(≡Si-O-)]ZrH (5b) (30%), coexistent with a (silylamido)(silyloxo)zirconium bishydride, [(≡Si-NH-)(≡Si-O-)] Zr(H)2 (5a) (45%), and a silylamidobis(silyloxo)zirconium monohydride, [(≡Si-NH-)(≡Si-O-)2]ZrH (5c) (25%). Surprisingly, nitrogen surface ligands possess catalytic properties already encountered with silicon oxide surfaces, but interestingly, catalyst (5) with chelating [N,O] shows better activity than (6) with chelating [N,N]. © 2013 American Chemical Society.

Estructura del macrobentos de la laguna de Paca, Junín

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Pedro Huamán

2013-06-01

Full Text Available Se caracterizó la estructura comunitaria del macrobentos de la laguna de Paca ubicada a 3364 msnm, a 11º 45 S y 75º 30’ W en el departamento de Junín-Perú. También se analizaron los principales factores físicos y químicos del agua y sedimentos que condicionan dicha estructura. Los muestreos se realizaron en el año 2000 en 8 estaciones, distribuidas en la zona litoral (5 y pelágica (3. En cada estación se tomaron muestras de agua cercana al fondo y de sedimentos para analizar los parámetros físicos, químicos y biológicos de la comunidad del macrobentos. Los datos fueron sometidos a pruebas univariadas y multivariadas para determinar el grado de interacción de los diversos factores con las variables biológicas. La diversidad del macrobentos es baja y muestra valores de diversidad menores a 1,5 y el número de especies menores a 11 especies. La abundancia varía en valores que van desde los 16 hasta 176 individuos/0,04 m2 . Tubifex tubifex y Chironomus sp. fueron las especies más resistentes a los altos valores de materia orgánica (35,22 a 38,28% y bajos valores de oxígeno disuelto (1 a 2 mg/L, lo que constituye indicadores biológicos de eutroficación.

NMR assignments of SPOC domain of the human transcriptional corepressor SHARP in complex with a C-terminal SMRT peptide.

Science.gov (United States)

Mikami, Suzuka; Kanaba, Teppei; Ito, Yutaka; Mishima, Masaki

2013-10-01

The transcriptional corepressor SMRT/HDAC1-associated repressor protein (SHARP) recruits histone deacetylases. Human SHARP protein is thought to function in processes involving steroid hormone responses and the Notch signaling pathway. SHARP consists of RNA recognition motifs (RRMs) in the N-terminal region and the spen paralog and ortholog C-terminal (SPOC) domain in the C-terminal region. It is known that the SPOC domain binds the LSD motif in the C-terminal tail of corepressors silencing mediator for retinoid and thyroid receptor (SMRT)/nuclear receptor corepressor (NcoR). We are interested in delineating the mechanism by which the SPOC domain recognizes the LSD motif of the C-terminal tail of SMRT/NcoR. To this end, we are investigating the tertiary structure of the SPOC/SMRT peptide using NMR. Herein, we report on the (1)H, (13)C and (15)N resonance assignments of the SPOC domain in complex with a SMRT peptide, which contributes towards a structural understanding of the SPOC/SMRT peptide and its molecular recognition.

BDNF restores the expression of Jun and Fos inducible transcription factors in the rat brain following repetitive electroconvulsive seizures.

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Hsieh, T F; Simler, S; Vergnes, M; Gass, P; Marescaux, C; Wiegand, S J; Zimmermann, M; Herdegen, T

1998-01-01

The expression of inducible transcription factors was studied following repetitive electroconvulsive seizures (ECS), c-Fos, c-Jun, JunB, and JunD immunoreactivities were investigated following a single (1 x ECS) or repetitive ECS evoked once per day for 4, 5, or 10 days (4 x ECS, 5 x ECS, or 10 x ECS). Animals were killed 3 or 12 h following the last ECS. Three hours after 1 x ECS, c-Fos was expressed throughout the cortex and hippocampus. After 5 x ECS and 10 x ECS, c-Fos was reexpressed in the CA4 area, but was completely absent in the other hippocampal areas and cortex. In these areas, c-Fos became only reinducible when the time lag between two ECS stimuli was 5 days. In contrast to c-Fos, intense JunB expression was inducible in the cortex and hippocampus, but not CA4 subfield, after 1 x ECS, 5 x ECS, and 10 x ECS. Repetitive ECS did not effect c-Jun and JunD expression. In a second model of systemic excitation of the brain, repetitive daily injection of kainic acid for 4 days completely failed to express c-Fos, c-Jun, and JunB after the last application whereas injection of kainic acid once per week did not alter the strong expressions compared to a single application of kainic acid. In order to study the maintenance of c-Fos expression during repetitive seizures, brain-derived neurotrophic factor (BDNF) was applied in parallel for 5 or 10 days via miniosmotic pumps and permanent cannula targeted at the hippocampus or the parietal cortex. Infusion of BDNF completely reinduced c-Fos expression during 5 x ECS or 10 x ECS in the cortex ipsilaterally to the cannula and, to a less extent, also increased the expression of c-Jun and JunB when compared to saline-treated controls. BDNF had no effect on the expression patterns in the hippocampus. ECS with or without BDNF infusion did not change the expression patterns of the constitutive transcription factors ATF-2, CREB, and SRF. These data demonstrate that various transcription factors substantially differ in their

Merkel cell polyomavirus in Merkel cell carcinogenesis: small T antigen-mediates c-Jun phosphorylation.

Science.gov (United States)

Wu, Julie H; Simonette, Rebecca A; Nguyen, Harrison P; Rady, Peter L; Tyring, Stephen K

2016-06-01

Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine skin cancer associated with the Merkel cell polyomavirus (MCPyV). The MCPyV genome, which is clonally integrated in the majority of MCCs, encodes the regulatory small T (sT) antigen. Previously, reports have established MCPyV sT antigen as a potent oncogene capable of inducing cell transformation. In the current study, we demonstrate a distinct role for c-Jun hyperactivation in MCPyV sT antigen pathogenesis. As MCPyV sT antigen's association with aggressive cancer growth has been previously established, this finding may represent a potential therapeutic target for the treatment of MCCs.

Synthesis and discovery of potent carbonic anhydrase, acetylcholinesterase, butyrylcholinesterase, and α-glycosidase enzymes inhibitors: The novel N,N'-bis-cyanomethylamine and alkoxymethylamine derivatives.

Science.gov (United States)

Taslimi, Parham; Caglayan, Cuneyt; Farzaliyev, Vagif; Nabiyev, Oruj; Sujayev, Afsun; Turkan, Fikret; Kaya, Ruya; Gulçin, İlhami

2018-04-01

During this investigation, N,N'-bis-azidomethylamines, N,N'-bis-cyanomethylamine, new alkoxymethylamine and chiral derivatives, which are considered to be a new generation of multifunctional compounds, were synthesized, functional properties were investigated, and anticholinergic and antidiabetic properties of those compounds were studied through the laboratory tests, and it was approved that they contain physiologically active compounds rather than analogues. Novel N-bis-cyanomethylamine and alkoxymethylamine derivatives were effective inhibitors of the α-glycosidase, cytosolic carbonic anhydrase I and II isoforms, butyrylcholinesterase (BChE), and acetylcholinesterase (AChE) with K i values in the range of 0.15-13.31 nM for α-glycosidase, 2.77-15.30 nM for human carbonic anhydrase isoenzymes I (hCA I), 3.12-21.90 nM for human carbonic anhydrase isoenzymes II (hCA II), 23.33-73.23 nM for AChE, and 3.84-48.41 nM for BChE, respectively. Indeed, the inhibition of these metabolic enzymes has been considered as a promising factor for pharmacologic intervention in a diversity of disturbances. © 2018 Wiley Periodicals, Inc.

Structural Insight into the Critical Role of the N-Terminal Region in the Catalytic Activity of Dual-Specificity Phosphatase 26.

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Eun-Young Won

Full Text Available Human dual-specificity phosphatase 26 (DUSP26 is a novel target for anticancer therapy because its dephosphorylation of the p53 tumor suppressor regulates the apoptosis of cancer cells. DUSP26 inhibition results in neuroblastoma cell cytotoxicity through p53-mediated apoptosis. Despite the previous structural studies of DUSP26 catalytic domain (residues 61-211, DUSP26-C, the high-resolution structure of its catalytically active form has not been resolved. In this study, we determined the crystal structure of a catalytically active form of DUSP26 (residues 39-211, DUSP26-N with an additional N-terminal region at 2.0 Å resolution. Unlike the C-terminal domain-swapped dimeric structure of DUSP26-C, the DUSP26-N (C152S monomer adopts a fold-back conformation of the C-terminal α8-helix and has an additional α1-helix in the N-terminal region. Consistent with the canonically active conformation of its protein tyrosine phosphate-binding loop (PTP loop observed in the structure, the phosphatase assay results demonstrated that DUSP26-N has significantly higher catalytic activity than DUSP26-C. Furthermore, size exclusion chromatography-multiangle laser scattering (SEC-MALS measurements showed that DUSP26-N (C152S exists as a monomer in solution. Notably, the crystal structure of DUSP26-N (C152S revealed that the N-terminal region of DUSP26-N (C152S serves a scaffolding role by positioning the surrounding α7-α8 loop for interaction with the PTP-loop through formation of an extensive hydrogen bond network, which seems to be critical in making the PTP-loop conformation competent for phosphatase activity. Our study provides the first high-resolution structure of a catalytically active form of DUSP26, which will contribute to the structure-based rational design of novel DUSP26-targeting anticancer therapeutics.

Towards the N-terminal acetylome

DEFF Research Database (Denmark)

Zhang, Xumin; Højrup, Peter

2013-01-01

Protein N-terminal acetylation (N(α)-acetylation) is observed widely from prokaryotes to eukaryotes. It gains increased importance in biological field, due to its multiple roles in many aspects of the protein life, such as assembly, stability, activity, and location. Today, mass spectrometry (MS...

Preparation of tritium labelled synthanecine A and its bis-N-ethylcarbamate

International Nuclear Information System (INIS)

Mattocks, A.R.

1982-01-01

A procedure is described for incorporating tritium into the 3-CH 2 side chain of synthanecine A, and preparing the carbamate, 2,3-bis-N-ethylcarbamoyloxymethyl-1-methyl-3-pyrroline, a hepatotoxic pyrrolizidine alkaloid analogue. The pyrrolizidine amino alcohol, retronecine, can be tritium labelled in a similar way. (author)

Preparation of tritium labelled synthanecine A and its bis-N-ethylcarbamate

Energy Technology Data Exchange (ETDEWEB)

Mattocks, A.R. (Medical Research Council, Carshalton (UK))

1982-04-01

A procedure is described for incorporating tritium into the 3-CH/sub 2/ side chain of synthanecine A, and preparing the carbamate, 2,3-bis-N-ethylcarbamoyloxymethyl-1-methyl-3-pyrroline, a hepatotoxic pyrrolizidine alkaloid analogue. The pyrrolizidine amino alcohol, retronecine, can be tritium labelled in a similar way.

Highly enantioselective catalytic cross-dehydrogenative coupling of N-carbamoyl tetrahydroisoquinolines and terminal alkynes.

Science.gov (United States)

Sun, Shutao; Li, Chengkun; Floreancig, Paul E; Lou, Hongxiang; Liu, Lei

2015-04-03

The first catalytic asymmetric cross-dehydrogenative coupling of cyclic carbamates and terminal alkynes has been established. The reaction features high enantiocontrol and excellent functional group tolerance and displays a wide range of structurally and electronically diverse carbamates as well as terminal alkynes. N-Acyl hemiaminals were identified as the reactive intermediates through preliminary control experiments. Employing readily removable carbamates as substrates rather than traditionally adopted N-aryl amines allows applications in complex molecule synthesis and therefore advances the C-H functionalization strategy to a synthetically useful level.

A two-dimensional ZnII coordination polymer constructed from benzene-1,2,3-tricarboxylic acid and N,N'-bis[(pyridin-4-yl)methylidene]hydrazine.

Science.gov (United States)

Wang, Xiangfei; Yang, Fang; Tang, Meng; Yuan, Limin; Liu, Wenlong

2015-07-01

The hydrothermal synthesis of the novel complex poly[aqua(μ4-benzene-1,2,3-tricarboxylato)[μ2-4,4'-(hydrazine-1,2-diylidenedimethanylylidene)dipyridine](μ3-hydroxido)dizinc(II)], [Zn(C9H3O6)(OH)(C12H10N4)(H2O)]n, is described. The benzene-1,2,3-tricarboxylate ligand connects neighbouring Zn4(OH)2 secondary building units (SBUs) producing an infinite one-dimensional chain. Adjacent one-dimensional chains are connected by the N,N'-bis[(pyridin-4-yl)methylidene]hydrazine ligand, forming a two-dimensional layered structure. Adjacent layers are stacked to generate a three-dimensional supramolecular architecture via O-H...O hydrogen-bond interactions. The thermal stability of this complex is described and the complex also appears to have potential for application as a luminescent material.

Identification and characterization of NDT 9513727 [N,N-bis(1,3-benzodioxol-5-ylmethyl)-1-butyl-2,4-diphenyl-1H-imidazole-5-methanamine], a novel, orally bioavailable C5a receptor inverse agonist.

Science.gov (United States)

Brodbeck, Robbin M; Cortright, Daniel N; Kieltyka, Andrzej P; Yu, Jianying; Baltazar, Carolyn O; Buck, Marianne E; Meade, Robin; Maynard, George D; Thurkauf, Andrew; Chien, Du-Shieng; Hutchison, Alan J; Krause, James E

2008-12-01

The complement system represents an innate immune mechanism of host defense that has three effector arms, the C3a receptor, the C5a receptor (C5aR), and the membrane attack complex. Because of its inflammatory and immune-enhancing properties, the biological activity of C5a and its classical receptor have been widely studied. Because specific antagonism of the C5aR could have therapeutic benefit without affecting the protective immune response, the C5aR continues to be a promising target for pharmaceutical research. The lack of specific, potent and orally bioavailable small-molecule antagonists has limited the clinical investigation of the C5aR. We report the discovery of NDT 9513727 [N,N-bis(1,3-benzodioxol-5-ylmethyl)-1-butyl-2,4-diphenyl-1H-imidazole-5-methanamine], a small-molecule, orally bioavailable, selective, and potent inverse agonist of the human C5aR. NDT 9513727 was discovered based on the integrated use of in vitro affinity and functional assays in conjunction with medicinal chemistry. NDT 9513727 inhibited C5a-stimulated responses, including guanosine 5'-3-O-(thio)triphosphate binding, Ca(2+) mobilization, oxidative burst, degranulation, cell surface CD11b expression and chemotaxis in various cell types with IC(50)s from 1.1 to 9.2 nM, respectively. In C5a competition radioligand binding experiments, NDT 9513727 exhibited an IC(50) of 11.6 nM. NDT 9513727 effectively inhibited C5a-induced neutropenia in gerbil and cynomolgus macaque in vivo. The findings suggest that NDT 9513727 may be a promising new entity for the treatment of human inflammatory diseases.

Carbamylation of N-terminal proline.

Science.gov (United States)

Olajuyigbe, Folasade M; Demitri, Nicola; Ajele, Joshua O; Maurizio, Elisa; Randaccio, Lucio; Geremia, Silvano

2010-09-09

Protein carbamylation is of great concern both in vivo and in vitro. Here, we report the first structural characterization of a protein carbamylated at the N-terminal proline. The unexpected carbamylation of the α-amino group of the least reactive codified amino acid has been detected in high-resolution electron density maps of a new crystal form of the HIV-1 protease/saquinavir complex. The carbamyl group is found coplanar to the proline ring with a trans conformation. The reaction of N-terminal with cyanate ion derived from the chaotropic agent urea was confirmed by mass spectra analysis on protease single crystals. Implications of carbamylation process in vitro and in vivo are discussed.

Bis(trialkylsilyl) peroxides as alkylating agents in the copper-catalyzed selective mono-N-alkylation of primary amides.

Science.gov (United States)

Sakamoto, Ryu; Sakurai, Shunya; Maruoka, Keiji

2017-06-13

The copper-catalyzed selective mono-N-alkylation of primary amides with bis(trialkylsilyl) peroxides as alkylating agents was reported. The results of a mechanistic study suggest that this reaction should proceed via a free radical process that includes the generation of alkyl radicals from bis(trialkylsilyl) peroxides.

Bis[μ-1,2-bis(1H-imidazol-1-ylmethylbenzene-κ2N3:N3′]disilver(I 3-carboxylato-4-hydroxybenzenesulfonate methanol solvate trihydrate

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Hong-Mei Sun

2009-09-01

Full Text Available In the title compound, [Ag2(C14H14N42](C7H4O6S·CH3OH·3H2O, the complex dication has a binuclear structure in which each AgI ion is two-coordinated in a slightly distorted linear coordination geometry. The two AgI atoms are bridged by two 1,2-bis[(1H-imidazol-1-ylmethyl]benzene (IBI ligands, forming a 22-membered ring. In the dication, π–π interactions are observed between the imidazole rings with centroid–centroid distances of 3.472 (3 and 3.636 (3 Å. In the crystal, the uncoordinated water molecules, anions and methanol solvent molecules are linked into chains along the b axis by O—H...O hydrogen bonds. In addition, π–π interactions are observed between the benzene rings of the IBI ligands, with a centroid–centroid distance of 3.776 (2 Å. The sulfonate group is disordered over two orientations with occupancies of 0.676 (12 and 0.324 (12.

Structural Basis for Toughness and Flexibility in the C-terminal Passenger Domain of an Acinetobacter Trimeric Autotransporter Adhesin*

Science.gov (United States)

Koiwai, Kotaro; Hartmann, Marcus D.; Linke, Dirk; Lupas, Andrei N.; Hori, Katsutoshi

2016-01-01

Trimeric autotransporter adhesins (TAAs) on the cell surface of Gram-negative pathogens mediate bacterial adhesion to host cells and extracellular matrix proteins. However, AtaA, a TAA in the nonpathogenic Acinetobacter sp. strain Tol 5, shows nonspecific high adhesiveness to abiotic material surfaces as well as to biotic surfaces. It consists of a passenger domain secreted by the C-terminal transmembrane anchor domain (TM), and the passenger domain contains an N-terminal head, N-terminal stalk, C-terminal head (Chead), and C-terminal stalk (Cstalk). The Chead-Cstalk-TM fragment, which is conserved in many Acinetobacter TAAs, has by itself the head-stalk-anchor architecture of a complete TAA. Here, we show the crystal structure of the Chead-Cstalk fragment, AtaA_C-terminal passenger domain (CPSD), providing the first view of several conserved TAA domains. The YadA-like head (Ylhead) of the fragment is capped by a unique structure (headCap), composed of three β-hairpins and a connector motif; it also contains a head insert motif (HIM1) before its last inner β-strand. The headCap, Ylhead, and HIM1 integrally form a stable Chead structure. Some of the major domains of the CPSD fragment are inherently flexible and provide bending sites for the fiber between segments whose toughness is ensured by topological chain exchange and hydrophobic core formation inside the trimer. Thus, although adherence assays using in-frame deletion mutants revealed that the characteristic adhesive sites of AtaA reside in its N-terminal part, the flexibility and toughness of the CPSD part provide the resilience that enables the adhesive properties of the full-length fiber across a wide range of conditions. PMID:26698633

catena-Poly[[copper(II-bis[μ-bis(3,5-dimethyl-1H-pyrazol-4-yl selenide

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Maksym Seredyuk

2009-11-01

Full Text Available In the title compound, {[Cu(C10H14N4Se2](ClO42}n, the CuII ion is located on a twofold rotation axis and has a tetragonally distorted square-planar geometry constituted by four N atoms. A pair of bis(3,5-dimethyl-1H-pyrazol-4-yl selenide (L ligands bridges the copper centers into a polymeric chain extending along [001]. The perchlorate anions are involved in intermolecular N—H...O hydrogen bonding, which links the chains into layers parallel to the bc plane.

Effects of alkyl chain length and substituent pattern of fullerene bis-adducts on film structures and photovoltaic properties of bulk heterojunction solar cells.

Science.gov (United States)

Tao, Ran; Umeyama, Tomokazu; Kurotobi, Kei; Imahori, Hiroshi

2014-10-08

A series of alkoxycarbonyl-substituted dihydronaphthyl-based [60]fullerene bis-adduct derivatives (denoted as C2BA, C4BA, and C6BA with the alkyl chain of ethyl, n-butyl, and n-hexyl, respectively) have been synthesized to investigate the effects of alkyl chain length and substituent pattern of fullerene bis-adducts on the film structures and photovoltaic properties of bulk heterojunction polymer solar cells. The shorter alkyl chain length caused lower solubility of the fullerene bis-adducts (C6BA > C4BA > C2BA), thereby resulting in the increased separation difficulty of respective bis-adduct isomers. The device performance based on poly(3-hexylthiophene) (P3HT) and the fullerene bis-adduct regioisomer mixtures was enhanced by shortening the alkyl chain length. When using the regioisomerically separated fullerene bis-adducts, the devices based on trans-2 and a mixture of trans-4 and e of C4BA exhibited the highest power conversion efficiencies of ca. 2.4%, which are considerably higher than those of the C6BA counterparts (ca. 1.4%) and the C4BA regioisomer mixture (1.10%). The film morphologies as well as electron mobilities of the P3HT:bis-adduct blend films were found to affect the photovoltaic properties considerably. These results reveal that the alkyl chain length and substituent pattern of fullerene bis-adducts significantly influence the photovoltaic properties as well as the film structures of bulk heterojunction solar cells.

Synthesis and characterization of phenylethynylcarbonyl terminated novel thermosetting imide compound

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H. Kimura

2013-02-01

Full Text Available Phenylethynyl terminated novel imide compound based on 1,3-bis(3-aminophenoxybenzene (APB and phenylethynyl trimellitic anhydride (PETA were prepared. The curing behavior of phenylethynyl terminated imide compound was investigated by differential scanning calorimetry and Fourier transform infrared spectrometry. The curing reaction of phenylethynylcarbonyl end group completed at 220°C, and proceeded much faster than that of phenylethynyl end group. Glass transition temperature of the thermosetting resin from phenylethynylcarbonyl terminated novel imide compound determined by dynamic mechanical analysis was almost the same as that of o-cresolnovolac type epoxy resin. In addition, the thermosetting resin from phenylethynylcarbonyl terminated novel imide compound exhibited excellent thermal and dimensional stabilities. These excellent properties of these phenylethynyl terminated imide compound might be due to the incorporation of alkene group or aromatic ring substitutes in the backbones, which might enhance the chain interaction (molecular packing and reduce the molecular chain mobility.

Aqua[bis(pyrimidin-2-yl-kappa N)amine](carbonato-kappa 2O,O')copper(II) dihydrate.

Science.gov (United States)

van Albada, Gerard A; Mutikainen, Ilpo; Turpeinen, Urho; Reedijk, Jan

2002-03-01

The title mononuclear complex, [Cu(CO(3))(C(8)H(7)N(5))(H(2)O)] x 2H(2)O, was obtained by fixation of CO(2) by a mixture of copper(II) tetrafluoroborate and the ligand bis(pyrimidin-2-yl)amine in ethanol/water. The Cu(II) ion of the complex has a distorted square-pyramidal environment, with a basal plane formed by two N atoms of the ligand and two chelating O atoms of the carbonate group, while the apical position is occupied by the O atom of the coordinating water molecule. In the solid state, hydrogen-bonding interactions are dominant, the most unusual being the Watson-Crick-type coplanar ligand pairing through two N--H...N bonds. Lattice water molecules also participate in hydrogen bonding.

C-terminal domains of bacterial proteases: structure, function and the biotechnological applications.

Science.gov (United States)

Huang, J; Wu, C; Liu, D; Yang, X; Wu, R; Zhang, J; Ma, C; He, H

2017-01-01

C-terminal domains widely exist in the C-terminal region of multidomain proteases. As a β-sandwich domain in multidomain protease, the C-terminal domain plays an important role in proteolysis including regulation of the secretory process, anchoring and swelling the substrate molecule, presenting as an inhibitor for the preprotease and adapting the protein structural flexibility and stability. In this review, the diversity, structural characteristics and biological function of C-terminal protease domains are described. Furthermore, the application prospects of C-terminal domains, including polycystic kidney disease, prepeptidase C-terminal and collagen-binding domain, in the area of medicine and biological artificial materials are also discussed. © 2016 The Society for Applied Microbiology.

An N-terminal peptide extension results in efficient expression, but not secretion, of a synthetic horseradish peroxidase gene in transgenic tobacco.

Science.gov (United States)

Kis, Mihaly; Burbridge, Emma; Brock, Ian W; Heggie, Laura; Dix, Philip J; Kavanagh, Tony A

2004-03-01

Native horseradish (Armoracia rusticana) peroxidase, HRP (EC 1.11.1.7), isoenzyme C is synthesized with N-terminal and C-terminal peptide extensions, believed to be associated with protein targeting. This study aimed to explore the specific functions of these extensions, and to generate transgenic plants with expression patterns suitable for exploring the role of peroxidase in plant development and defence. Transgenic Nicotiana tabacum (tobacco) plants expressing different versions of a synthetic horseradish peroxidase, HRP, isoenzyme C gene were constructed. The gene was engineered to include additional sequences coding for either the natural N-terminal or the C-terminal extension or both. These constructs were placed under the control of a constitutive promoter (CaMV-35S) or the tobacco RUBISCO-SSU light inducible promoter (SSU) and introduced into tobacco using Agrobacterium-mediated transformation. To study the effects of the N- and C-terminal extensions, the localization of recombinant peroxidase was determined using biochemical and molecular techniques. Transgenic tobacco plants can exhibit a ten-fold increase in peroxidase activity compared with wild-type tobacco levels, and the majority of this activity is located in the symplast. The N-terminal extension is essential for the production of high levels of recombinant protein, while the C-terminal extension has little effect. Differences in levels of enzyme activity and recombinant protein are reflected in transcript levels. There is no evidence to support either preferential secretion or vacuolar targeting of recombinant peroxidase in this heterologous expression system. This leads us to question the postulated targeting roles of these peptide extensions. The N-terminal extension is essential for high level expression and appears to influence transcript stability or translational efficiency. Plants have been generated with greatly elevated cytosolic peroxidase activity, and smaller increases in apoplastic

Small interference RNA-mediated knockdown of sperm associated antigen 9 having structural homology with c-Jun N-terminal kinase-interacting protein

International Nuclear Information System (INIS)

Rana, Ritu; Jagadish, Nirmala; Garg, Manoj; Mishra, Deepshikha; Dahiya, Neetu; Chaurasiya, Dipak; Suri, Anil

2006-01-01

Recently, we reported a novel testis-specific sperm associated antigen 9 (SPAG9) protein, a new member of the JNK-interacting protein family, having a functional role in sperm-egg fusion [N. Jagadish, R. Rana, R. Selvi, D. Mishra, M. Garg, S. Yadav, J.C. Herr, K. Okumura, A. Hasegawa, K. Koyama, A. Suri, Biochem. J. 389 (2005) 73-82]. NCBI Blast searches revealed SPAG9 nucleotide sequence similarities with ESTs of various cancerous tissues. In the present study, we compared the efficiency of two independent SPAG9 specific small interfering RNA (siRNA) constructs, BS/U6/spag9 and BS/U6/spag9-I, to ablate the SPAG9 expression in mammalian cells. A positive correlation between the ratio of target gene versus siRNA and the suppression of SPAG9 expression was observed. Further, the cotransfection of BS/U6/spag9 with pcDNA-SPAG9 and pFlag-CMV2-JNK-3 resulted in specific suppression of SPAG9 without affecting JNK-3 expression. The present investigation will eventually extend the application of SPAG9 siRNA in in vivo targeting experiments that aim to define the SPAG9 functional genomics in tumor and reproductive biology

Synthesis and Biodistribution of Lipophilic Monocationic Gallium Radiopharmaceuticals Derived from N,N′-bis(3-aminopropyl)-N,N′-dimethylethylenediamine: Potential Agents for PET Myocardial Imaging with 68Ga

Science.gov (United States)

Hsiao, Yui-May; Mathias, Carla J.; Wey, Shiaw-Pyng; Fanwick, Phillip E.; Green, Mark A.

2009-01-01

Introduction In locations that lack nearby cyclotron facilities for radionuclide production, generator-based 68Ga-radiopharmaceuticals might have clinical utility for positron emission tomography (PET) studies of myocardial perfusion and other physiologic processes. Methods The lipophilic, monocationic 67Ga-labeled gallium chelates of five novel hexadentate bis(salicylaldimine) ligands, the bis(salicylaldimine), bis(3-methoxysalicylaldimine), bis(4-methoxysalicylaldimine), bis(6-methoxysalicylaldimine), and bis(4,6-dimethoxysalicylaldimine) of N,N′-bis(3-aminopropyl)-N,N′-dimethylethylenediamine (BAPDMEN), were prepared. The structure of the unlabeled [Ga(4-MeOsal)2BAPDMEN]+PF6− salt was determined by X-ray crystallography, and the biodistribution of each of the 67Ga-labeled gallium chelates determined in rats following i.v. administration and compared to the biodistribution of [86Rb]rubidium chloride. Results The [Ga(4-MeOsal)2BAPDMEN]+PF6− complex exhibits the expected pseudo-octahedral N4O22− coordination sphere about the Ga3+ center with a trans-disposition of the phenolate oxygen atoms. All five of the 67Ga-radiopharmaceuticals were found to afford the desired myocardial retention of the radiogallium. The [67/68Ga][Ga(3-MeOsal)2BAPDMEN]1+ radiopharmaceutical appears to have the best properties for myocardial imaging, exhibiting 2% of the injected dose in the heart at both 1-minute and 2-hours post-injection and very high heart/non-target ratios (heart/blood ratios of 7.6 ± 1.0 and 54 ± 10 at 1-min and 120-min, respectively; heart/liver ratios of 1.8 ± 0.4 and 39 ± 3 at 1-min and 120-min, respectively). Conclusions Most of these new agents, particularly [67/68Ga][Ga(3-MeOsal)2BAPDMEN]1+, would appear superior to previously reported bis(salicyaldimines) of N,N′-bis(3-aminopropyl)ethylenediamine as candidates for PET imaging of the heart with 68Ga. PMID:19181267

A non-catalytic N-terminal domain negatively influences the nucleotide exchange activity of translation elongation factor 1Bα.

Science.gov (United States)

Trosiuk, Tetiana V; Shalak, Vyacheslav F; Szczepanowski, Roman H; Negrutskii, Boris S; El'skaya, Anna V

2016-02-01

Eukaryotic translation elongation factor 1Bα (eEF1Bα) is a functional homolog of the bacterial factor EF-Ts, and is a component of the macromolecular eEF1B complex. eEF1Bα functions as a catalyst of guanine nucleotide exchange on translation elongation factor 1A (eEF1A). The C-terminal domain of eEF1Bα is necessary and sufficient for its catalytic activity, whereas the N-terminal domain interacts with eukaryotic translation elongation factor 1Bγ (eEF1Bγ) to form a tight complex. However, eEF1Bγ has been shown to enhance the catalytic activity of eEF1Bα attributed to the C-terminal domain of eEF1Bα. This suggests that the N-terminal domain of eEF1Bα may in some way influence the guanine nucleotide exchange process. We have shown that full-length recombinant eEF1Bα and its truncated forms are non-globular proteins with elongated shapes. Truncation of the N-terminal domain of eEF1Bα, which is dispensable for catalytic activity, resulted in acceleration of the rate of guanine nucleotide exchange on eEF1A compared to full-length eEF1Bα. A similar effect on the catalytic activity of eEF1Bα was observed after its interaction with eEF1Bγ. We suggest that the non-catalytic N-terminal domain of eEF1Bα may interfere with eEF1A binding to the C-terminal catalytic domain, resulting in a decrease in the overall rate of the guanine nucleotide exchange reaction. Formation of a tight complex between the eEF1Bγ and eEF1Bα N-terminal domains abolishes this inhibitory effect. © 2015 FEBS.

Solvothermal synthesis and characterisation of new one-dimensional indium and gallium sulphides: [C1N4H26]0.5[InS2] and [C1N4H26]0.5[GaS2

International Nuclear Information System (INIS)

Vaqueiro, Paz

2006-01-01

Two new main group metal sulphides, [C 1 N 4 H 26 ] 0.5 [InS 2 ] (1) and [C 1 N 4 H 26 ] 0.5 [GaS 2 ] (2) have been prepared solvothermally in the presence of 1,4-bis(3-aminopropyl)piperazine and their crystal structures determined by single-crystal X-ray diffraction. Both compounds are isostructural and crystallise in the monoclinic space group P2 1 /n (Z=4), with a=6.5628(5), b=11.2008(9), c=12.6611(9) A and β=94.410(4) o (wR=0.035) for compound (1) and a=6.1094(5), b=11.2469(9), c=12.7064(10) A and β=94.313(4) o (wR=0.021) for compound (2). The structure of [C 1 N 4 H 26 ] 0.5 [MS 2 ] (M=In,Ga) consists of one-dimensional [MS 2 ] - chains which run parallel to the crystallographic a axis and are separated by diprotonated amine molecules. These materials represent the first example of solvothermally prepared one-dimensional gallium and indium sulphides. -- Graphical abstract: [C 1 N 4 H 26 ] 0.5 [InS 2 ] and [C 1 N 4 H 26 ] 0.5 [GaS 2 ], prepared under solvothermal conditions, consist of one-dimensional [MS 2 ] - chains separated by diprotonated 1,4-bis(3-aminopropyl)piperazine molecules

Loss of connective tissue growth factor as an unfavorable prognosis factor activates miR-18b by PI3K/AKT/C-Jun and C-Myc and promotes cell growth in nasopharyngeal carcinoma.

Science.gov (United States)

Yu, X; Zhen, Y; Yang, H; Wang, H; Zhou, Y; Wang, E; Marincola, F M; Mai, C; Chen, Y; Wei, H; Song, Y; Lyu, X; Ye, Y; Cai, L; Wu, Q; Zhao, M; Hua, S; Fu, Q; Zhang, Y; Yao, K; Liu, Z; Li, X; Fang, W

2013-05-16

Connective tissue growth factor (CTGF) has different roles in different types of cancer. However, the involvement and molecular basis of CTGF in tumor progression and prognosis of human nasopharyngeal carcinoma (NPC) have almost never been reported. In this study, we observed that downregulated CTGF expression was significantly associated with NPC progression and poor prognosis. Knockdown of CTGF markedly elevated the ability of cell proliferation in vivo and in vitro. Subsequently, we discovered that the reduction of CTGF increased the expression of miR-18b, an oncomir-promoting cell proliferation. Further, we discovered that attenuated CTGF-mediated upregulation of miR-18b was dependent on the increased binding of transcription factors Jun proto-oncogene (C-Jun) and v-Myc myelocytomatosis viral oncogene homolog (C-Myc) to miR-18b promoter region via phosphoinositide 3-kinase (PI3K)/AKT pathway. Finally, we further found that miR-18b directly suppressed the expression of CTGF in NPC. In clinical fresh specimens, miR-18b was widely overexpressed and inversely correlated with CTGF expression in NPC. Our studies are the first to demonstrate that reduced CTGF as an unfavorable prognosis factor mediates the activation of miR-18b, an oncomir directly suppresses CTGF expression, by PI3K/AKT/C-Jun and C-Myc and promotes cell growth of NPC.

A continuous record of glacial-interglacial cycles spanning more than 500 kyr from Lake Junín, Perú

Science.gov (United States)

Rodbell, D. T.; Abbott, M. B.; McGee, D.; Chen, C. Y.; Stoner, J. S.; Hatfield, R. G.; Tapia, P. M.; Bush, M. B.; Weidhaas, N.; Woods, A.; Valero-Garces, B. L.; Lehmann, S. B.; Bustamante, M. G.; Larsen, D. J.

2017-12-01

Lake Junín (11.0°S, 76.2°W) is a shallow (zmax 12 m), intermontane, high-elevation (4080 masl) lake in the inner-tropics of the Southern Hemisphere that spans 300 km2. It is dammed by coalescing alluvial fans that are >250 ka that emanate from glacial valleys. Lake Junín has not been overrun by glacial ice in several hundred thousand years and is ideally located to receive glacigenic sediment. The Junín basin is underlain by carbonate rocks that have provided a source of Ca and HCO3 ions; precipitation of CaCO3 in the western margin of the lake during the present interglacial period has occurred at 1mm yr-1. An airgun seismic survey revealed a strong reflector at 105 meters depth, which marks the base of the lacustrine section. Drilling focused on three sites. Site 1, located near the depocenter and most distal to glacial sources, yielded a composite sediment thickness of 95m; Site 2, proximal to glacial outwash fans, yielded a composite thickness of 28 m; Site 3, located at an intermediate distance yielded a sediment thickness of 55m. The stratigraphy of Site 1 is marked by 8 glacial/interglacial cycles; the latter are characterized by low bulk density and magnetic susceptibility (MS) and high CaCO3. These units are intercalated with glacigenic sediment that has high density and MS, and low CaCO3. The age model for Site 1 is based on AMS radiocarbon dates on terrestrial macrofossils and dozens of U/Th ages on authigenic CaCO3. Strong and protracted interglacial periods appear to be associated with intervals of reduced variability of solar insolation in the Southern Hemisphere tropics. During these intervals there is strong covariation (r2>0.9) between the δ13C and δ18O of authigenic calcium carbonate, and δ18O values are relatively enriched (-12 to -2‰); examples include interglacial periods correlative with marine isotope stages (MIS) 1, 13, and 15. The magnitude of tropical glaciation appears to have been greater during glacial cycles prior to the LGM

Crystal and Molecular Structure of Bis(2,2-diphenyl-N-(di-n-propylcarbamothioyl acetamidocopper(II Complex

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Hakan Arslan

2011-01-01

Full Text Available Bis(2,2-diphenyl-N-(di-n-propylcarbamothioyl acetamidocopper(II complex has been synthesized and characterized by elemental analysis and FT-IR spectroscopy. The crystal and molecular structure of the title compound has been determined from single crystal X-ray diffraction data. It crystallizes in the triclinic space group P-1, with a = 13.046(2 Å, b = 13.135(2 Å, c = 13.179(2 Å, α= 67.083(4°, β= 67.968(4°, γ = 84.756(4° and Dcalc =1.330 g/cm3 for Z = 2. The crystal structure confirms that the complex is a mononuclear copper(II complex and the 2,2-diphenyl-N-(di-n-propyl-carbamothioylacetamide ligand is a bidentate chelating ligand, coordinating to the copper atom through the thiocarbonyl and carbonyl groups. This coordination has a slightly distorted square-planar geometry (O1-Cu1-O2: 86.48(11°, O1-Cu1-S1: 93.85(9°, O2-Cu1-S2: 94.20(9° and S1-Cu1-S2: 91.21(4°. The title molecule shows a cis-arrangement and C–O, C–S and C–N bond lengths of the complex suggest considerable electronic delocalization in the chelate rings.

NetAcet: prediction of N-terminal acetylation sites

DEFF Research Database (Denmark)

Kiemer, Lars; Bendtsen, Jannick Dyrløv; Blom, Nikolaj

2005-01-01

Summary: We present here a neural network based method for prediction of N-terminal acetylation-by far the most abundant post-translational modification in eukaryotes. The method was developed on a yeast dataset for N-acetyltransferase A (NatA) acetylation, which is the type of N-acetylation for ......Summary: We present here a neural network based method for prediction of N-terminal acetylation-by far the most abundant post-translational modification in eukaryotes. The method was developed on a yeast dataset for N-acetyltransferase A (NatA) acetylation, which is the type of N...

The catalytic chain of human complement subcomponent C1r. Purification and N-terminal amino acid sequences of the major cyanogen bromide-cleavage fragments.

Science.gov (United States)

Arlaud, G J; Gagnon, J; Porter, R R

1982-01-01

1. The a- and b-chains of reduced and alkylated human complement subcomponent C1r were separated by high-pressure gel-permeation chromatography and isolated in good yield and in pure form. 2. CNBr cleavage of C1r b-chain yielded eight major peptides, which were purified by gel filtration and high-pressure reversed-phase chromatography. As determined from the sum of their amino acid compositions, these peptides accounted for a minimum molecular weight of 28 000, close to the value 29 100 calculated from the whole b-chain. 3. N-Terminal sequence determinations of C1r b-chain and its CNBr-cleavage peptides allowed the identification of about two-thirds of the amino acids of C1r b-chain. From our results, and on the basis of homology with other serine proteinases, an alignment of the eight CNBr-cleavage peptides from C1r b-chain is proposed. 4. The residues forming the 'charge-relay' system of the active site of serine proteinases (His-57, Asp-102 and Ser-195 in the chymotrypsinogen numbering) are found in the corresponding regions of C1r b-chain, and the amino acid sequence around these residues has been determined. 5. The N-terminal sequence of C1r b-chain has been extended to residue 60 and reveals that C1r b-chain lacks the 'histidine loop', a disulphide bond that is present in all other known serine proteinases.

Atomic Layer Deposition of Silicon Nitride from Bis(tert-butylamino)silane and N2 Plasma.

Science.gov (United States)

Knoops, Harm C M; Braeken, Eline M J; de Peuter, Koen; Potts, Stephen E; Haukka, Suvi; Pore, Viljami; Kessels, Wilhelmus M M

2015-09-09

Atomic layer deposition (ALD) of silicon nitride (SiNx) is deemed essential for a variety of applications in nanoelectronics, such as gate spacer layers in transistors. In this work an ALD process using bis(tert-butylamino)silane (BTBAS) and N2 plasma was developed and studied. The process exhibited a wide temperature window starting from room temperature up to 500 °C. The material properties and wet-etch rates were investigated as a function of plasma exposure time, plasma pressure, and substrate table temperature. Table temperatures of 300-500 °C yielded a high material quality and a composition close to Si3N4 was obtained at 500 °C (N/Si=1.4±0.1, mass density=2.9±0.1 g/cm3, refractive index=1.96±0.03). Low wet-etch rates of ∼1 nm/min were obtained for films deposited at table temperatures of 400 °C and higher, similar to that achieved in the literature using low-pressure chemical vapor deposition of SiNx at >700 °C. For novel applications requiring significantly lower temperatures, the temperature window from room temperature to 200 °C can be a solution, where relatively high material quality was obtained when operating at low plasma pressures or long plasma exposure times.

Poly[bis[μ4-N-(2-hydroxyiminopropionyl-N′-(2-oxidoiminopropionylpropane-1,3-diaminato]dimethanolcalciumdicopper(II

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Valentina A. Kalibabchuk

2009-09-01

Full Text Available In the title compound, [CaCu2(C9H13N4O42(CH3OH2]n, the CaII atom lies on an inversion center and is situated in a moderately distorted octahedral environment. The CuII atom is in a distorted square-pyramidal geometry, defined by four N atoms belonging to the amide and oxime groups of the triply deprotonated residue of N,N′-bis(2-hydroxyiminopropanoylpropane-1,3-diamine (H4pap and one oxime O atom from a neighboring Hpap ligand at the apical site, forming a dimeric [Cu2(Hpap2]2− unit. Each dimeric unit connects four Ca atoms and each Ca atom links four [Cu2(Hpap2]2− units through Ca—O(amide bonds, leading to a three-dimensional framework. The crystal structure involves intra- and intermolecular O—H...O hydrogen bonds.

EL CRITERIO DE INTERPRETACIÓN DEL PRINCIPIO NON BIS IN ÍDEM PREVISTO EN EL ARTÍCULO 45.3 DE LA CONSTITUCIÓN ESPAÑOLA

OpenAIRE

María Lourdes,Ramírez Torrado

2010-01-01

Respecto a la lectura constitucional del principio se propone una interpretación complementaria y diversa a la hasta ahora presentada por la doctrina constitucional y científica que insisten en derivar el sustento constitucional del postulado non bis in ídem del artículo 25. Desconociendo lo anterior, una disposición constitucional que prevé tácitamente el non bis in ídem al establecer un criterio para determinar cuál es la sanción o el procedimiento a imponer sin quebrantar la prohibición bi...

War Termination, Identity Conflict, and Genocide: A Road Map

Science.gov (United States)

2012-05-17

of The Cambodian Genocide Project, and the Vice President of the International Association of Genocide Scholars. 10 Genocide Watch, “About Genocide ...Approved for Public Release; Distribution is Unlimited War Termination, Identity Conflict, and Genocide : A Road Map A Monograph by MAJ Stephen...TYPE SAMS Monograph 3. DATES COVERED (From - To) JUN 2011 – MAY 2012 4. TITLE AND SUBTITLE War Termination, Identity Conflict, and Genocide : A

Steric and electronic parameters of a bulky yet flexible N-heterocyclic carbene: 1,3-bis(2,6-bis(1-ethylpropyl)phenyl)imidazol-2-ylidene (IPent)

KAUST Repository

Collado, Alba; Balogh, Já nos; Meiries, Sé bastien; Slawin, Alexandra M. Z.; Falivene, Laura; Cavallo, Luigi; Nolan, Steven P.

2013-01-01

The free N-heterocyclic carbene IPent (1; IPent = 1,3-bis(2,6-bis(1- ethylpropyl)phenyl)imidazol-2-ylidene) was prepared from the corresponding imidazolium chloride salt (2). The steric and electronic parameters of 1 were determined by synthesis of the gold(I) chloride complex [Au(IPent)Cl] (3) and the nickel-carbonyl complex [Ni(IPent)(CO)3] (4), respectively. 3 and 4 were fully characterized by NMR spectroscopy, elemental analysis, and X-ray diffraction studies on single crystals. © 2013 American Chemical Society.

Steric and electronic parameters of a bulky yet flexible N-heterocyclic carbene: 1,3-bis(2,6-bis(1-ethylpropyl)phenyl)imidazol-2-ylidene (IPent)

KAUST Repository

Collado, Alba

2013-06-10

The free N-heterocyclic carbene IPent (1; IPent = 1,3-bis(2,6-bis(1- ethylpropyl)phenyl)imidazol-2-ylidene) was prepared from the corresponding imidazolium chloride salt (2). The steric and electronic parameters of 1 were determined by synthesis of the gold(I) chloride complex [Au(IPent)Cl] (3) and the nickel-carbonyl complex [Ni(IPent)(CO)3] (4), respectively. 3 and 4 were fully characterized by NMR spectroscopy, elemental analysis, and X-ray diffraction studies on single crystals. © 2013 American Chemical Society.

Antimicrobial activity of human prion protein is mediated by its N-terminal region.

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Mukesh Pasupuleti

Full Text Available BACKGROUND: Cellular prion-related protein (PrP(c is a cell-surface protein that is ubiquitously expressed in the human body. The multifunctionality of PrP(c, and presence of an exposed cationic and heparin-binding N-terminus, a feature characterizing many antimicrobial peptides, made us hypothesize that PrP(c could exert antimicrobial activity. METHODOLOGY AND PRINCIPAL FINDINGS: Intact recombinant PrP exerted antibacterial and antifungal effects at normal and low pH. Studies employing recombinant PrP and N- and C-terminally truncated variants, as well as overlapping peptide 20mers, demonstrated that the antimicrobial activity is mediated by the unstructured N-terminal part of the protein. Synthetic peptides of the N-terminus of PrP killed the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, and the Gram-positive Bacillus subtilis and Staphylococcus aureus, as well as the fungus Candida parapsilosis. Fluorescence studies of peptide-treated bacteria, paired with analysis of peptide effects on liposomes, showed that the peptides exerted membrane-breaking effects similar to those seen after treatment with the "classical" human antimicrobial peptide LL-37. In contrast to LL-37, however, no marked helix induction was detected for the PrP-derived peptides in presence of negatively charged (bacteria-mimicking liposomes. PrP furthermore showed an inducible expression during wounding of human skin ex vivo and in vivo, as well as stimulation of keratinocytes with TGF-alpha in vitro. CONCLUSIONS: The demonstration of an antimicrobial activity of PrP, localisation of its activity to the N-terminal and heparin-binding region, combined with results showing an increased expression of PrP during wounding, indicate that PrPs could have a previously undisclosed role in host defense.

Synthesis and characterization of thermally stable poly(amide-imide-montmorillonite nanocomposites based on bis(4-carboxyphenyl-N,N'-pyromellitimide acid

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M. Hajibeygi

2013-04-01

Full Text Available Two new poly(amide-imide-montmorillonite reinforced nanocomposites containing bis(4-carboxyphenyl-N,N'-pyromellitimide acid moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide-imide (PAI as a source of polymer matrix was synthesized by the direct polycondensation reaction of bis(4-carboxyphenyl-N,N'-pyromellitimide acid with 4,4'-diamino diphenyl sulfone in the presence of triphenyl phosphite (TPP, CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP. Morphology and structure of the resulting PAI-nanocomposite films with 10 and 20% silicate particles were characterized by FT-IR spectroscopy, X-ray diffraction (XRD and scanning electron microscopy (SEM. The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposites films were investigated by using UV-Vis spectroscopy, thermal gravimetry analysis (TGA and water uptake measurements.DOI: http://dx.doi.org/10.4314/bcse.v27i1.10

Synthesis of the mevalonic acid labelled with "1"4C, "1"3C and "3H

International Nuclear Information System (INIS)

Rousseau, Bernard

1982-01-01

This thesis describes five new methods of synthesis of the (R,S) mevalonic acid adapted to the labelling with "1"4C and "1"3C in positions 4,5 or 5 or 3', or with tritium in position 3'. Three of them use the tri-oxa-2,4,10 adamantyl group as masked carboxyl function. The two others take benefit from the regioselectivity of the bis-hydro-boration of terminal acetylenics by the 9-borabicyclo [3-3-1]nonane. The acylation of the bis-trimethylsilyl lithiomalonate, and the chemistry of dithiannes are also involved. Acetylene and methyl iodide labelled with isotopes are used as cheap base products [fr

Apoptotic Activity of MeCP2 Is Enhanced by C-Terminal Truncating Mutations.

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Alison A Williams

Full Text Available Methyl-CpG binding protein 2 (MeCP2 is a widely abundant, multifunctional protein most highly expressed in post-mitotic neurons. Mutations causing Rett syndrome and related neurodevelopmental disorders have been identified along the entire MECP2 locus, but symptoms vary depending on mutation type and location. C-terminal mutations are prevalent, but little is known about the function of the MeCP2 C-terminus. We employ the genetic efficiency of Drosophila to provide evidence that expression of p.Arg294* (more commonly identified as R294X, a human MECP2 E2 mutant allele causing truncation of the C-terminal domains, promotes apoptosis of identified neurons in vivo. We confirm this novel finding in HEK293T cells and then use Drosophila to map the region critical for neuronal apoptosis to a small sequence at the end of the C-terminal domain. In vitro studies in mammalian systems previously indicated a role of the MeCP2 E2 isoform in apoptosis, which is facilitated by phosphorylation at serine 80 (S80 and decreased by interactions with the forkhead protein FoxG1. We confirm the roles of S80 phosphorylation and forkhead domain transcription factors in affecting MeCP2-induced apoptosis in Drosophila in vivo, thus indicating mechanistic conservation between flies and mammalian cells. Our findings are consistent with a model in which C- and N-terminal interactions are required for healthy function of MeCP2.

Abl N-terminal Cap stabilization of SH3 domain dynamics†

OpenAIRE

Chen, Shugui; Dumitrescu, Teodora Pene; Smithgall, Thomas E.; Engen, John R.

2008-01-01

Crystal structures and other biochemical data indicate that the N-terminal cap (NCap) region of the Abelson tyrosine kinase (c-Abl) is important for maintaining the downregulated conformation of the kinase domain. The exact contributions that NCap makes in stabilizing the various intramolecular interactions within c-Abl are less clear. While the NCap appears important for locking the SH3/SH2 domains to the back of the kinase domain, there may be other more subtle elements of regulation. Hydro...

Surprisingly Different Reaction Behavior of Alkali and Alkaline Earth Metal Bis(trimethylsilyl)amides toward Bulky N-(2-Pyridylethyl)-N'-(2,6-diisopropylphenyl)pivalamidine.

Science.gov (United States)

Kalden, Diana; Oberheide, Ansgar; Loh, Claas; Görls, Helmar; Krieck, Sven; Westerhausen, Matthias

2016-07-25

N-(2,6-Diisopropylphenyl)-N'-(2-pyridylethyl)pivalamidine (Dipp-N=C(tBu)-N(H)-C2 H4 -Py) (1), reacts with metalation reagents of lithium, magnesium, calcium, and strontium to give the corresponding pivalamidinates [(tmeda)Li{Dipp-N=C(tBu)-N-C2 H4 -Py}] (6), [Mg{Dipp-N=C(tBu)-N-C2 H4 -Py}2 ] (3), and heteroleptic [{(Me3 Si)2 N}Ae{Dipp-N=C(tBu)-N-C2 H4 -Py}], with Ae being Ca (2 a) and Sr (2 b). In contrast to this straightforward deprotonation of the amidine units, the reaction of 1 with the bis(trimethylsilyl)amides of sodium or potassium unexpectedly leads to a β-metalation and an immediate deamidation reaction yielding [(thf)2 Na{Dipp-N=C(tBu)-N(H)}] (4 a) or [(thf)2 K{Dipp-N=C(tBu)-N(H)}] (4 b), respectively, as well as 2-vinylpyridine in both cases. The lithium derivative shows a similar reaction behavior to the alkaline earth metal congeners, underlining the diagonal relationship in the periodic table. Protonation of 4 a or the metathesis reaction of 4 b with CaI2 in tetrahydrofuran yields N-(2,6-diisopropylphenyl)pivalamidine (Dipp-N=C(tBu)-NH2 ) (5), or [(thf)4 Ca{Dipp-N=C(tBu)-N(H)}2 ] (7), respectively. The reaction of AN(SiMe3 )2 (A=Na, K) with less bulky formamidine Dipp-N=C(H)-N(H)-C2 H4 -Py (8) leads to deprotonation of the amidine functionality, and [(thf)Na{Dipp-N=C(H)-N-C2 H4 -Py}]2 (9 a) or [(thf)K{Dipp-N=C(H)-N-C2 H4 -Py}]2 (9 b), respectively, are isolated as dinuclear complexes. From these experiments it is obvious, that β-metalation/deamidation of N-(2-pyridylethyl)amidines requires bases with soft metal ions and also steric pressure. The isomeric forms of all compounds are verified by single-crystal X-ray structure analysis and are maintained in solution. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quando o índice bispectral (BIS pode fornecer valores espúrios Cuando el índice bispectral (BIS puede suministrar valores falsos When the bispectral index (Bis can give false results

Directory of Open Access Journals (Sweden)

Leonardo Teixeira Domingues Duarte

2009-02-01

Full Text Available JUSTIFICATIVA E OBJETIVOS: O índice bispectral (BIS é um parâmetro multifatorial derivado do eletroencefalograma (EEG que permite a monitorização do componente hipnótico da anestesia. Foi obtido a partir de algoritmo derivado da análise de grande número de EEGs de voluntários e pacientes submetidos a sedações e anestesia geral com diferentes agentes anestésicos. Além de outros benefícios, o uso do BIS para monitorização da profundidade da anestesia reduz a ocorrência de despertar e memória intra-operatória. Esta revisão teve o objetivo de apresentar situações clínicas em que o BIS aponta valores espúrios, falsamente elevados ou reduzidos, em decorrência de condições do paciente ou ações de anestésicos não-previstos quando da elaboração do seu algoritmo. CONTEÚDO: Os valores do BIS podem sofrer alteração e influência em variadas situações clínicas em que há padrões anormais do EEG; efeito de diferentes anestésicos e outros fármacos não-incluídos na elaboração de seu algoritmo; interferência de equipamentos elétricos; bem como decorrentes de peculiaridades do monitor. CONCLUSÃO: Apesar de o algoritmo do BIS ter sofrido diversas alterações desde a sua primeira versão, essas situações que determinam variações espúrias dos valores do BIS devem ser reconhecidas pelo anestesiologista a fim de evitar complicações, sejam conseqüentes à sobredose anestésica, sejam por subdoses que poderão causar despertar e memória intra-operatória.JUSTIFICATIVA Y OBJETIVOS: El índice bispectral (BIS es un parámetro multifactorial derivado del electroencefalograma (EEG, que permite la monitorización del componente hipnótico de la anestesia. Fue obtenido a partir de algoritmo derivado del análisis de un gran número de EEG de voluntarios y pacientes sometidos a sedaciones y anestesia general con diferentes agentes anestésicos. Además de otros beneficios, el uso del BIS para la monitorización de la

catena-Poly[[copper(II)-bis[μ-bis(3,5-dimethyl-1H-pyrazol-4-yl) selenide

Science.gov (United States)

Seredyuk, Maksym; Haukka, Matti; Pavlenko, Vadim A.; Fritsky, Igor O.

2009-01-01

In the title compound, {[Cu(C10H14N4Se)2](ClO4)2}n, the CuII ion is located on a twofold rotation axis and has a tetra­gonally distorted square-planar geometry constituted by four N atoms. A pair of bis(3,5-dimethyl-1H-pyrazol-4-yl) selenide (L) ligands bridges the copper centers into a polymeric chain extending along [001]. The perchlorate anions are involved in inter­molecular N—H⋯O hydrogen bonding, which links the chains into layers parallel to the bc plane. PMID:21578140

Facile, novel two-step syntheses of benzimidazoles, bis-benzimidazoles, and bis-benzimidazole-dihydroquinoxalines.

Science.gov (United States)

Xu, Zhigang; Shaw, Arthur Y; Dietrich, Justin; Cappelli, Alexandra P; Nichol, Gary; Hulme, Christopher

2012-02-01

Three scaffolds of benzimidazoles, bis-benzimidazoles, and bis-benzimidazole-dihydroquinoxalines were synthesized via Ugi/de-protection/cyclization methodology. Benzimidazole forming ring closure was enabled under microwave irradiation in the presence of 10% TFA/DCE. The methodology demonstrates the utility of 2-(N-Boc-amino)-phenyl-isocyanide for the generation of new molecular diversity.

Facile, novel two-step syntheses of benzimidazoles, bis-benzimidazoles, and bis-benzimidazole-dihydroquinoxalines

OpenAIRE

Xu, Zhigang; Shaw, Arthur Y.; Dietrich, Justin; Cappelli, Alexandra P.; Nichol, Gary; Hulme, Christopher

2012-01-01

Three scaffolds of benzimidazoles, bis-benzimidazoles, and bis-benzimidazole-dihydroquinoxalines were synthesized via Ugi/de-protection/cyclization methodology. Benzimidazole forming ring closure was enabled under microwave irradiation in the presence of 10% TFA/DCE. The methodology demonstrates the utility of 2-(N-Boc-amino)-phenyl-isocyanide for the generation of new molecular diversity.

The unique N-terminal zinc finger of synaptotagmin-like protein 4 reveals FYVE structure.

Science.gov (United States)

Miyamoto, Kazuhide; Nakatani, Arisa; Saito, Kazuki

2017-12-01

Synaptotagmin-like protein 4 (Slp4), expressed in human platelets, is associated with dense granule release. Slp4 is comprised of the N-terminal zinc finger, Slp homology domain, and C2 domains. We synthesized a compact construct (the Slp4N peptide) corresponding to the Slp4 N-terminal zinc finger. Herein, we have determined the solution structure of the Slp4N peptide by nuclear magnetic resonance (NMR). Furthermore, experimental, chemical modification of Cys residues revealed that the Slp4N peptide binds two zinc atoms to mediate proper folding. NMR data showed that eight Cys residues coordinate zinc atoms in a cross-brace fashion. The Simple Modular Architecture Research Tool database predicted the structure of Slp4N as a RING finger. However, the actual structure of the Slp4N peptide adopts a unique C 4 C 4 -type FYVE fold and is distinct from a RING fold. To create an artificial RING finger (ARF) with specific ubiquitin-conjugating enzyme (E2)-binding capability, cross-brace structures with eight zinc-ligating residues are needed as the scaffold. The cross-brace structure of the Slp4N peptide could be utilized as the scaffold for the design of ARFs. © 2017 The Protein Society.

Diminished excretion of polyamines from BHK-21/C13 cells exposed to methylglyoxal bis(guanylhydrazone).

Science.gov (United States)

Melvin, M A; Keir, H M

1978-01-01

Methylglyoxal bis(guanylhydrazone) (1,1'-[methylethanediylidine)dinitrilo]diguanidine) inhibited the growth of BHK-21/C13 cells in monolayer cultures. Accumulation of spermidine and spermine was inhibited, whereas the accumulation of putrescine was increased. The intracellular spermidine/spermine molar ratio decreased conly slightly after exposure of the cells to 20 micrometer-methylglyoxal bis(guanylhydrazone) for 1 day. Cells incubated in the presence of the drug released less polyamine into the culture medium that did control cells, the polyamine released consisting almost exclusively of spermidine, both free and as a conjugated form. PMID:697761

Structural implications of the C-terminal tail in the catalytic and stability properties of manganese peroxidases from ligninolytic fungi

Energy Technology Data Exchange (ETDEWEB)

Fernández-Fueyo, Elena [CSIC, Ramiro de Maeztu 9, 28040 Madrid (Spain); Acebes, Sandra [Barcelona Supercomputing Center, Jordi Girona 29, 08034 Barcelona (Spain); Ruiz-Dueñas, Francisco J.; Martínez, María Jesús; Romero, Antonio; Medrano, Francisco Javier, E-mail: fjmedrano@cib.csic.es [CSIC, Ramiro de Maeztu 9, 28040 Madrid (Spain); Guallar, Victor, E-mail: fjmedrano@cib.csic.es [Barcelona Supercomputing Center, Jordi Girona 29, 08034 Barcelona (Spain); ICREA, Passeig Lluís Companys 23, 08010 Barcelona (Spain); Martínez, Angel T., E-mail: fjmedrano@cib.csic.es [CSIC, Ramiro de Maeztu 9, 28040 Madrid (Spain)

2014-12-01

The variable C-terminal tail of manganese peroxidases, a group of enzymes involved in lignin degradation, is implicated in their catalytic and stability properties, as shown by new crystal structures, molecular-simulation and directed-mutagenesis data. Based on this structural–functional evaluation, short and long/extralong manganese peroxidase subfamilies have been accepted; the latter are characterized by exceptional stability, while it is shown for the first time that the former are able to oxidize other substrates at the same site where manganese(II) is oxidized. The genome of Ceriporiopsis subvermispora includes 13 manganese peroxidase (MnP) genes representative of the three subfamilies described in ligninolytic fungi, which share an Mn{sup 2+}-oxidation site and have varying lengths of the C-terminal tail. Short, long and extralong MnPs were heterologously expressed and biochemically characterized, and the first structure of an extralong MnP was solved. Its C-terminal tail surrounds the haem-propionate access channel, contributing to Mn{sup 2+} oxidation by the internal propionate, but prevents the oxidation of 2, 2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS), which is only oxidized by short MnPs and by shortened-tail variants from site-directed mutagenesis. The tail, which is anchored by numerous contacts, not only affects the catalytic properties of long/extralong MnPs but is also associated with their high acidic stability. Cd{sup 2+} binds at the Mn{sup 2+}-oxidation site and competitively inhibits oxidation of both Mn{sup 2+} and ABTS. Moreover, mutations blocking the haem-propionate channel prevent substrate oxidation. This agrees with molecular simulations that position ABTS at an electron-transfer distance from the haem propionates of an in silico shortened-tail form, while it cannot reach this position in the extralong MnP crystal structure. Only small differences exist between the long and the extralong MnPs, which do not justify their

Asparagine 326 in the extremely C-terminal region of XRCC4 is essential for the cell survival after irradiation

Energy Technology Data Exchange (ETDEWEB)

Wanotayan, Rujira; Fukuchi, Mikoto; Imamichi, Shoji; Sharma, Mukesh Kumar; Matsumoto, Yoshihisa, E-mail: yoshim@nr.titech.ac.jp

2015-02-20

XRCC4 is one of the crucial proteins in the repair of DNA double-strand break (DSB) through non-homologous end-joining (NHEJ). As XRCC4 consists of 336 amino acids, N-terminal 200 amino acids include domains for dimerization and for association with DNA ligase IV and XLF and shown to be essential for XRCC4 function in DSB repair and V(D)J recombination. On the other hand, the role of the remaining C-terminal region of XRCC4 is not well understood. In the present study, we noticed that a stretch of ∼20 amino acids located at the extreme C-terminus of XRCC4 is highly conserved among vertebrate species. To explore its possible importance, series of mutants in this region were constructed and assessed for the functionality in terms of ability to rescue radiosensitivity of M10 cells lacking XRCC4. Among 13 mutants, M10 transfectant with N326L mutant (M10-XRCC4{sup N326L}) showed elevated radiosensitivity. N326L protein showed defective nuclear localization. N326L sequence matched the consensus sequence of nuclear export signal. Leptomycin B treatment accumulated XRCC4{sup N326L} in the nucleus but only partially rescued radiosensitivity of M10-XRCC4{sup N326L}. These results collectively indicated that the functional defects of XRCC4{sup N326L} might be partially, but not solely, due to its exclusion from nucleus by synthetic nuclear export signal. Further mutation of XRCC4 Asn326 to other amino acids, i.e., alanine, aspartic acid or glutamine did not affect the nuclear localization but still exhibited radiosensitivity. The present results indicated the importance of the extremely C-terminal region of XRCC4 and, especially, Asn326 therein. - Highlights: • Extremely C-terminal region of XRCC4 is highly conserved among vertebrate species. • XRCC4 C-terminal point mutants, R325F and N326L, are functionally deficient in terms of survival after irradiation. • N326L localizes to the cytoplasm because of synthetic nuclear export signal. • Leptomycin B restores the

[μ-1,2-Bis(diphenylphosphinoethane-κ2P:P′]bis{[1,2-bis(diphenylphosphinoethane-κ2P,P′]cyanidocopper(I} methanol disolvate

Directory of Open Access Journals (Sweden)

Rong Wang

2010-08-01

Full Text Available The title centrosymmetric complex, [Cu2(CN2(C26H24P23]·2CH3OH, consists of two five-membered [Cu(dppeCN] rings [dppe is 1,2-bis(diphenylphosphinoethane] bridged by one μ2-dppe ligand, and two methanol solvent molecules. The angles around the central metal atom indicate that each CuI atom is located in the center of a distorted tetrahedron. The coordination sphere of each CuI atom is formed by three P atoms from two dppe ligands, and one C atom from the cyanide ligand. The crystal structure is stabilized by O—H...N hydrogen bonds, which are formed by the O—H donor group from methanol and the N-atom acceptor from a cyanide ligand.

Crystal structures of the dioxane hemisolvates of N-(7-bromomethyl-1,8-naphthyridin-2-ylacetamide and bis[N-(7-dibromomethyl-1,8-naphthyridin-2-ylacetamide

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Robert Rosin

2017-10-01

Full Text Available The syntheses and crystal structures of N-(7-bromomethyl-1,8-naphthyridin-2-ylacetamide dioxane hemisolvate, C11H10BrN3O·0.5C4H8O2, (I, and bis[N-(7-dibromomethyl-1,8-naphthyridin-2-ylacetamide] dioxane hemisolvate, 2C11H9Br2N3O·0.5C4H8O2, (II, are described. The molecules adopt a conformation with the N—H hydrogen pointing towards the lone electron pair of the adjacent naphthyridine N atom. The crystals of (I are stabilized by a three-dimensional supramolecular network comprising N—H...N, C—H...N and C—H...O hydrogen bonds, as well as C—Br...π halogen bonds. The crystals of compound (II are stabilized by a three-dimensional supramolecular network comprising N—H...N, C—H...N and C—H...O hydrogen bonds, as well as C—H...π contacts and C—Br...π halogen bonds. The structure of the substituent attached in the 7-position of the naphthyridine skeleton has a fundamental influence on the pattern of intermolecular noncovalent bonding. While the Br atom of (I participates in weak C—Br...Oguest and C—Br...π contacts, the Br atoms of compound (II are involved in host–host interactions via C—Br...O=C, C—Br...N and C—Br...π bonding.

CLARIFICAREA PRINCIPIULUI NON BIS IN IDEM ÎN CAZURI DE CONDAMNARE A PERSOANELOR PENTRU CRIMELE CONTRA UMANITĂŢII

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George LAZĂR

2016-03-01

Full Text Available Problema ştiinţifică de importanţă majoră abordată în cadrul acestui mesaj ştiinţific rezidă în identificarea particu­la­ri­tăţilor aplicării principiului non bis in idem în cadrul urmăririi penale, extrădării şi pedepsirii persoanelor care au comis crime împotriva umanităţii.Pentru a obţine un răspuns clar şi exhaustiv la acest subiect, urmează să ne aprofundăm în analiza doctrinei procesual penale generale ale principiului non bis in idem, precum şi a unor surse ştiinţifice speciale consacrate problemelor de aplicare a acestui principiu în cazul crimelor contra umanităţii. Clarification concerning the principle of non bis in idem in the cases of persons’ conviction for crimes against humanity The major scientific problem which has been analyzed in the realm of this scientific research is considered to be identification of the peculiarities of the principle non bis in idem in the process of criminal prosecution, extradition and criminal punishment of the persons who have committed crimes against humanity.In order to obtain a clear answer regarding this problem we have to be involved in the doctrinaire analysis of the criminal procedure theory of non bis in idem principle, as well as of some special scientific problems of its application in the cases of crimes against humanity.

Epidemiología y caracterización de los factores de riesgo de diarrea viral bovina y neosporosis en bovinos del valle del Mantaro – región Junín

OpenAIRE

Arauco Villar, Fernando

2015-01-01

Se realizó un estudio epidemiológico de Diarrea viral bovina (DVB) y neosporosis en 425 vacas en producción de 37 hatos del Valle del Mantaro-Región Junín, Perú, mediante ELISA e identificando sus factores de riesgo aplicando una encuesta. Para DVB se encontraron prevalencias: muestral 66.33%, predial 97.3% (36/37) y promedio/hato 64.78%, Concepción tuvo las prevalencias promedio/hato y muestral más altas, luego Jauja, Chupaca y Huancayo; la prevalencia de animales persistentement...

Di-μ-chlorido-bis{chlorido[(R/(S-1,5-diphenyl-3-(2-pyridyl-κN-2-pyrazoline-κN2]zinc(II}

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Miquel Barceló-Oliver

2010-08-01

Full Text Available In the centrosymmetric binuclear title compound, [Zn2Cl4(C20H17N32], the coordination geometry of the ZnII ion can be described as a distorted ZnN2Cl3 trigonal bipyramid (τ = 0.89, arising from the N,N′-bidentate ligand, a terminal chloride ion and two bridging chloride ions. The N atoms occupy one axial and one equatorial site and the terminal chloride ion occupies an equatorial site. The dihedral angle between the pyridine and pyrazole rings is 12.8 (2°. In the crystal, aromatic π–π stacking [centroid–centroid separations = 3.812 (3 and 3.848 (3 Å] and C—H...Cl and C—H...π interactions help to establish the packing.

Suppression of cell death by the secretory form of N-terminal ERC/mesothelin.

Science.gov (United States)

Wang, Tegexibaiyin; Kajino, Kazunori; Abe, Masaaki; Tan, Ke; Maruo, Masumi; Sun, Guodong; Hagiwara, Yoshiaki; Maeda, Masahiro; Hino, Okio

2010-08-01

ERC/mesothelin is highly expressed in malignant mesothelioma, pancreatic cancer, and ovarian cancer. It is cleaved to a 30 kDa N-terminal secretory form (N-ERC) and a 40 kDa C-terminal membranous form (C-ERC). Several functions have been reported for full-length ERC (full-ERC) and C-ERC/mesothelin, such as in cell adhesion and invasion, stimulation of cell proliferation, and the suppression of cell death. However, there have been no studies to date on the function of secretory N-ERC, despite the fact that it is abundantly secreted into the sera of mesothelioma patients. In this study, we investigated whether N-ERC could function as a secretory factor to stimulate tumor progression. Full-, N, or C-ERC was overexpressed in the human hepatocellular carcinoma cell line Huh7 that lacks endogenous expression of ERC/mesothelin. Changes in the rates of cell proliferation and cell death were determined, and the state of signal transducers was examined using various endpoints: total cell counts, trypan blue exclusion rate, BrdU incorporation rate, TUNEL assay, and the phosphorylation of ERK1/2 and Stat3. In cells overexpressing N-ERC, phosphorylation of ERK1/2 was enhanced and the rate of cell death decreased, leading to the increase of cell number. The culture medium containing the secretory N-ERC also had the activity to increase the number of cells. Our data suggested that one of the full-ERC functions reported previously was mediated by the secretory N-ERC.

One-pot synthesis of 4,8-dibromobenzo[1,2-c;4,5-c']bis[1,2,5]thiadiazole.

Science.gov (United States)

Tam, Teck Lip; Li, Hairong; Wei, Fengxia; Tan, Ke Jie; Kloc, Christian; Lam, Yeng Ming; Mhaisalkar, Subodh G; Grimsdale, Andrew C

2010-08-06

A one-step synthesis of 4,8-dibromobenzo[1,2-c;4,5-c']bis[1,2,5]thiadiazole with use of 1,2,4,5-tetraaminobenzene tetrahydrobromide and thionyl bromide in good yield is reported. This unit can then be used in the synthesis of low bandgap materials via palladium-catalyzed coupling reactions. The approach offers a quick and easy way to prepare low bandgap materials as compared to the current literature methods.

Tungsten(VI) Carbyne/Bis(carbene) Tautomerization Enabled by N-Donor SBA15 Surface Ligands: A Solid-State NMR and DFT Study

KAUST Repository

Bendjeriou-Sedjerari, Anissa

2016-08-11

Designing supported well-defined bis(carbene) complexes remains a key challenge in heterogeneous catalysis. The reaction of W(CtBu)(CH(2)tBu)(3) with amine-modified mesoporous SBA15 silica, which has vicinal silanol/silylamine pairs [(SiOH)(SiNH2)], leads to [(SiNH2-)(SiO-)W(CHtBu)(CH(2)tBu)(2)] and [(SiNH2-)(SiO-)W(=CHtBu)(2)(CH(2)tBu). Variable temperature, H-1-H-1 2D double-quantum, H-1-C-13 HETCOR, and HETCOR with spin diffusion solid-state NMR spectroscopy demonstrate tautomerization between the alkyl alkylidyne and the bis(alkylidene) on the SBA15 surface. Such equilibrium is possible through the coordination of W to the surface [(Si-OH)(Si-NH2)] groups, which act as a [N,O] pincer ligand. DFT calculations provide a rationalization for the surface-complex tautomerization and support the experimental results. This direct observation of such a process shows the strong similarity between molecular mechanisms in homogeneous and heterogeneous catalysis. In propane metathesis (at 150 degrees C), the tungsten bis(carbene) tautomer is favorable, with a turnover number (TON) of 262. It is the highest TON among all the tungsten alkyl-supported catalysts.

Tungsten(VI) Carbyne/Bis(carbene) Tautomerization Enabled by N-Donor SBA15 Surface Ligands: A Solid-State NMR and DFT Study

KAUST Repository

Bendjeriou-Sedjerari, Anissa; Sofack-Kreutzer, Julien; Minenkov, Yury; Abou-Hamad, Edy; Hamzaoui, Bilel; Werghi, Baraa; Anjum, Dalaver H.; Cavallo, Luigi; Huang, Kuo-Wei; Basset, Jean-Marie

2016-01-01

Designing supported well-defined bis(carbene) complexes remains a key challenge in heterogeneous catalysis. The reaction of W(CtBu)(CH(2)tBu)(3) with amine-modified mesoporous SBA15 silica, which has vicinal silanol/silylamine pairs [(SiOH)(SiNH2)], leads to [(SiNH2-)(SiO-)W(CHtBu)(CH(2)tBu)(2)] and [(SiNH2-)(SiO-)W(=CHtBu)(2)(CH(2)tBu). Variable temperature, H-1-H-1 2D double-quantum, H-1-C-13 HETCOR, and HETCOR with spin diffusion solid-state NMR spectroscopy demonstrate tautomerization between the alkyl alkylidyne and the bis(alkylidene) on the SBA15 surface. Such equilibrium is possible through the coordination of W to the surface [(Si-OH)(Si-NH2)] groups, which act as a [N,O] pincer ligand. DFT calculations provide a rationalization for the surface-complex tautomerization and support the experimental results. This direct observation of such a process shows the strong similarity between molecular mechanisms in homogeneous and heterogeneous catalysis. In propane metathesis (at 150 degrees C), the tungsten bis(carbene) tautomer is favorable, with a turnover number (TON) of 262. It is the highest TON among all the tungsten alkyl-supported catalysts.

Jun Wang

Indian Academy of Sciences (India)

0.32O2 solid solution on depositing -alumina washcoat on .... Volume 38 Issue 5 September 2015 pp 1435-1438. High-performance aqueous rechargeable batteries based on zinc anode and NiCo2O4 cathode · Jun Wang Zhijun Jia Songbo Li ...

Porphyrin amino acids-amide coupling, redox and photophysical properties of bis(porphyrin) amides.

Science.gov (United States)

Melomedov, Jascha; Wünsche von Leupoldt, Anica; Meister, Michael; Laquai, Frédéric; Heinze, Katja

2013-07-14

New trans-AB2C meso-substituted porphyrin amino acid esters with meso-substituents of tunable electron withdrawing power (B = mesityl, 4-C6H4F, 4-C6H4CF3, C6F5) were prepared as free amines 3a-3d, as N-acetylated derivatives Ac-3a-Ac-3d and corresponding zinc(II) complexes Zn-Ac-3a-Zn-Ac-3d. Several amide-linked bis(porphyrins) with a tunable electron density at each porphyrin site were obtained from the amino porphyrin precursors by condensation reactions (4a-4d) and mono- and bis(zinc(II)) complexes Zn(2)-4d and Zn(1)Zn(2)-4d were prepared. The electronic interaction between individual porphyrin units in bis(porphyrins) 4 is probed by electrochemical experiments (CV, EPR), electronic absorption spectroscopy, steady-state and time-resolved fluorescence spectroscopy in combination with DFT/PCM calculations on diamagnetic neutral bis(porphyrins) 4 and on respective charged mixed-valent radicals 4(+/-). The interaction via the -C6H4-NHCO-C6H4- bridge, the site of oxidation and reduction and the lowest excited singlet state S1, is tuned by the substituents on the individual porphyrins and the metalation state.

c-Jun amino-terminal kinase-1 mediates glucose-responsive upregulation of the RNA editing enzyme ADAR2 in pancreatic beta-cells.

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Liu Yang

Full Text Available A-to-I RNA editing catalyzed by the two main members of the adenosine deaminase acting on RNA (ADAR family, ADAR1 and ADAR2, represents a RNA-based recoding mechanism implicated in a variety of cellular processes. Previously we have demonstrated that the expression of ADAR2 in pancreatic islet β-cells is responsive to the metabolic cues and ADAR2 deficiency affects regulated cellular exocytosis. To investigate the molecular mechanism by which ADAR2 is metabolically regulated, we found that in cultured β-cells and primary islets, the stress-activated protein kinase JNK1 mediates the upregulation of ADAR2 in response to changes of the nutritional state. In parallel with glucose induction of ADAR2 expression, JNK phosphorylation was concurrently increased in insulin-secreting INS-1 β-cells. Pharmacological inhibition of JNKs or siRNA knockdown of the expression of JNK1 prominently suppressed glucose-augmented ADAR2 expression, resulting in decreased efficiency of ADAR2 auto-editing. Consistently, the mRNA expression of Adar2 was selectively reduced in the islets from JNK1 null mice in comparison with that of wild-type littermates or JNK2 null mice, and ablation of JNK1 diminished high-fat diet-induced Adar2 expression in the islets from JNK1 null mice. Furthermore, promoter analysis of the mouse Adar2 gene identified a glucose-responsive region and revealed the transcription factor c-Jun as a driver of Adar2 transcription. Taken together, these results demonstrate that JNK1 serves as a crucial component in mediating glucose-responsive upregulation of ADAR2 expression in pancreatic β-cells. Thus, the JNK1 pathway may be functionally linked to the nutrient-sensing actions of ADAR2-mediated RNA editing in professional secretory cells.

Kaposi's sarcoma herpesvirus C-terminal LANA concentrates at pericentromeric and peri-telomeric regions of a subset of mitotic chromosomes

International Nuclear Information System (INIS)

Kelley-Clarke, Brenna; Ballestas, Mary E.; Komatsu, Takashi; Kaye, Kenneth M.

2007-01-01

The Kaposi's sarcoma-associated herpesvirus (KSHV) latency-associated nuclear antigen (LANA) tethers KSHV terminal repeat (TR) DNA to mitotic chromosomes to efficiently segregate episomes to progeny nuclei. LANA contains N- and C-terminal chromosome binding regions. We now show that C-terminal LANA preferentially concentrates to paired dots at pericentromeric and peri-telomeric regions of a subset of mitotic chromosomes through residues 996-1139. Deletions within C-terminal LANA abolished both self-association and chromosome binding, consistent with a requirement for self-association to bind chromosomes. A deletion abolishing TR DNA binding did not affect chromosome targeting, indicating LANA's localization is not due to binding its recognition sequence in chromosomal DNA. LANA distributed similarly on human and non-human mitotic chromosomes. These results are consistent with C-terminal LANA interacting with a cell factor that concentrates at pericentromeric and peri-telomeric regions of mitotic chromosomes

Poly[[[diisothiocyanatocobalt(II]-bis[μ-4-tert-butyl-2,6-bis(1,2,4-triazol-1-ylmethylphenol

Directory of Open Access Journals (Sweden)

2009-03-01

Full Text Available In the title compound, {[Co(NCS2(C16H20N6O2]·2C3H7NO·2H2O}n, each CoII ion located on an inversion center is six-coordinated by four equatorial N atoms from four different 4-tert-butyl-2,6-bis(1,2,4-triazol-1-ylmethylphenol (L ligands, and by two N atoms from two axial thiocyanate anions [Co—N = 2.104 (3–2.144 (3 Å]. The metal centres are connected via the bidentate L ligands into two-dimensional polymeric layers parallel to bc plane. The dimethylformamide and solvent water molecules participate in intermolecular O—H...O and O—H...S hydrogen bonds, which consolidate the crystal packing.

Structure of the N-terminal region of Haemophilus Influenzae HI0017: Implications for function

International Nuclear Information System (INIS)

Yu Liping; Mack, Jamey; Hajduk, Phil; Fesik, Stephen W.

2001-01-01

Haemophilus influenzae is a gram-negative pathogen that causes infections ranging from asymptomatic colonization of the human upper respiratory tract to serious invasive diseases such as meningitis. Although the genome of Haemophilus influenzae has been completely sequenced, the structure and function of many of these proteins are unknown. HI0017 is one of these uncharacterized proteins. Here we describe the three-dimensional solution structure of the N-terminal portion of HI0017 as determined by NMR spectroscopy. The structure consists of a five-stranded antiparallel β-sheet and two short α-helices. It is similar to the C-terminal domain of Diphtheria toxin repressor (DtxR). The C-terminal portion of HI0017 has an amino acid sequence that closely resembles pyruvate formate-lyase - an enzyme that converts pyruvate and CoA into acetyl-CoA and formate by a radical mechanism. Based on structural and sequence comparisons, we propose that the C-terminus of HI0017 functions as an enzyme with a glycyl radical mechanism, while the N-terminus participates in protein/protein interactions involving an activase (iron-sulfur protein) and/or the substrate

Structure of the N-terminal region of Haemophilus Influenzae HI0017: Implications for function

Energy Technology Data Exchange (ETDEWEB)

Yu Liping; Mack, Jamey; Hajduk, Phil; Fesik, Stephen W. [Abbott Laboratories, Pharmaceutical Discovery Division, D46Y, AP10/LL (United States)

2001-06-15

Haemophilus influenzae is a gram-negative pathogen that causes infections ranging from asymptomatic colonization of the human upper respiratory tract to serious invasive diseases such as meningitis. Although the genome of Haemophilus influenzae has been completely sequenced, the structure and function of many of these proteins are unknown. HI0017 is one of these uncharacterized proteins. Here we describe the three-dimensional solution structure of the N-terminal portion of HI0017 as determined by NMR spectroscopy. The structure consists of a five-stranded antiparallel {beta}-sheet and two short {alpha}-helices. It is similar to the C-terminal domain of Diphtheria toxin repressor (DtxR). The C-terminal portion of HI0017 has an amino acid sequence that closely resembles pyruvate formate-lyase - an enzyme that converts pyruvate and CoA into acetyl-CoA and formate by a radical mechanism. Based on structural and sequence comparisons, we propose that the C-terminus of HI0017 functions as an enzyme with a glycyl radical mechanism, while the N-terminus participates in protein/protein interactions involving an activase (iron-sulfur protein) and/or the substrate.

Impregnation of chelating agent 3,3-bis-N,N bis-(carboxymethylaminomethyl-o-cresolsulfonephthalein in biopolymer chitosan: adsorption equilibrium of Cu(II in aqueous medium

Directory of Open Access Journals (Sweden)

Luciano Vitali

2006-06-01

Full Text Available The aim of this study was to impregnate the chelating agent 3,3-bis-N,N,bis-(carboxymethylaminomethyl-o-cresolsulfonephthalein in chitosan and to investigate the adsorption of Cu(II ions. The chemical modification was confirmed by FTIR spectrometry, thermogravimetric analysis (TGA and energy dispersive x-ray spectroscopy (EDX. The adsorption studies were carried out with Cu(II ions in a batch process and were shown to be dependent on pH. The adsorption kinetics was tested using three models: pseudo first-order, pseudo second order and intraparticle diffusion. The experimental kinetics data were best fitted with the pseudo second-order model (R² = 0.999, which provided a rate constant, k2, of 1.21 x 10-3 g mg-1 min-1. The adsorption rate depended on the concentration of Cu(II ions on the adsorbent surface and on the quantity of Cu(II ions adsorbed at equilibrium. The Langmuir isotherm model provided the best fit for the equilibrium data in the concentration range investigated, with the maximum adsorption capacity being 81.0 mg of Cu(II per gram of adsorbent, as obtained from the linear equation of the isotherm. Desorption tests revealed that around 90% of the adsorbed metal was removed, using EDTA solution as the eluent. This result suggests that the polymeric matrix can be reused.

N-terminal and C-terminal heparin-binding domain polypeptides derived from fibronectin reduce adhesion and invasion of liver cancer cells

International Nuclear Information System (INIS)

Tang, Nan-Hong; Chen, Yan-Lin; Wang, Xiao-Qian; Li, Xiu-Jin; Wu, Yong; Zou, Qi-Lian; Chen, Yuan-Zhong

2010-01-01

Fibronectin (FN) is known to be a large multifunction glycoprotein with binding sites for many substances, including N-terminal and C-terminal heparin-binding domains. We investigated the effects of highly purified rhFNHN29 and rhFNHC36 polypeptides originally cloned from the two heparin-binding domains on the adhesion and invasion of highly metastatic human hepatocellular carcinoma cells (MHCC97H) and analyzed the underlying mechanism involved. The MHCC97H cells that adhered to FN in the presence of various concentrations of rhFNHN29 and rhFNHC36 polypeptides were stained with crystal violet and measured, and the effects of rhFNHN29 and rhFNHC36 on the invasion of the MHCC97H cells were then detected using the Matrigel invasion assay as well as a lung-metastasis mouse model. The expression level of integrins and focal adhesion kinase (FAK) phosphotyrosyl protein was examined by Western blot, and the activity of matrix metalloproteinases (MMPs) and activator protein 1 (AP-1) was analyzed by gelatin zymography and the electrophoretic mobility band-shift assay (EMSA), respectively. Both of the polypeptides rhFNHN29 and rhFNHC36 inhibited adhesion and invasion of MHCC97H cells; however, rhFNHC36 exhibited inhibition at a lower dose than rhFNHN29. These inhibitory effects were mediated by integrin αvβ3 and reversed by a protein tyrosine phosphatase inhibitor. Polypeptides rhFNHN29 and rhFNHC36 abrogated the tyrosine phosphorylation of focal adhesion kinase (p-FAK) and activation of activator protein 1 (AP-1), resulting in the decrease of integrin αv, β3 and β1 expression as well as the reduction of MMP-9 activity. Polypeptides rhFNHN29 and rhFNHC36 could potentially be applicable to human liver cancer as anti-adhesive and anti-invasive agents

Structure of the Escherichia coli RNA polymerase α subunit C-terminal domain

International Nuclear Information System (INIS)

Lara-González, Samuel; Birktoft, Jens J.; Lawson, Catherine L.

2010-01-01

The crystal structure of the dimethyllysine derivative of the E. coli RNA polymerase α subunit C-terminal domain is reported at 2.0 Å resolution. The α subunit C-terminal domain (αCTD) of RNA polymerase (RNAP) is a key element in transcription activation in Escherichia coli, possessing determinants responsible for the interaction of RNAP with DNA and with transcription factors. Here, the crystal structure of E. coli αCTD (α subunit residues 245–329) determined to 2.0 Å resolution is reported. Crystals were obtained after reductive methylation of the recombinantly expressed domain. The crystals belonged to space group P2 1 and possessed both pseudo-translational symmetry and pseudo-merohedral twinning. The refined coordinate model (R factor = 0.193, R free = 0.236) has improved geometry compared with prior lower resolution determinations of the αCTD structure [Jeon et al. (1995 ▶), Science, 270, 1495–1497; Benoff et al. (2002 ▶), Science, 297, 1562–1566]. An extensive dimerization interface formed primarily by N- and C-terminal residues is also observed. The new coordinates will facilitate the improved modeling of αCTD-containing multi-component complexes visualized at lower resolution using X-ray crystallography and electron-microscopy reconstruction

Aryl hydrocarbon receptor pathway activation enhances gastric cancer cell invasiveness likely through a c-Jun-dependent induction of matrix metalloproteinase-9

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Song Xin

2009-04-01

Full Text Available Abstract Background Abberant aryl hydrocarbon receptor (AhR expression and AhR pathway activation are involved in gastric carcinogenesis. However, the relationship between AhR pathway activation and gastric cancer progression is still unclear. In present study, we used 2,3,7,8-tetrachlorodibenzo-para-dioxin (TCDD, a classic and most potent ligand of AhR, to activate AhR pathway and investigated the effect of AhR pathway activation on human gastric cancer AGS cell invasion and explored the corresponding mechanism. Results To determine whether AhR pathway can be activated in AGS cells, we examined the expression of CYP1A1, a classic target gene of AhR pathway, following TCDD exposure. RT-PCR and western blot analysis showed that both CYP1A1 mRNA and protein expression were increased in a dose-dependent manner following TCDD treatment and AhR antagonist resveratrol (RSV could reverse this TCDD-induced CYP1A1 expression. To determine whether TCDD treatment of AGS cells results in an induction of MMP-9 expression, we detected MMP-9 mRNA using RT-PCR and detected MMP-9 enzymatic activity using gelatin zymography. The results showed that both MMP-9 mRNA expression and enzymatic activity were gradually increased with the concentration increase of TCDD in media and these changes could be reversed by RSV treatment in a dose-dependent manner. To examine whether AhR activation-induced MMP-9 expression and activity in AGS cells results in increased migration and invasion, we performed wound healing migration assay and transwell migration and invasion assay. After TCDD treatment, the migration distance and the migration and invasion abilities of AGS cells were increased with a dose-dependent manner. To demonstrate AhR activation-induced MMP-9 expression is mediated by c-Jun, siRNA transfection was performed to silence c-Jun mRNA in AGS cells. The results showed that MMP-9 mRNA expression and activity in untreated control AGS cells were very weak; After TCDD

A novel calmodulin-regulated Ca2+-ATPase (ACA2) from Arabidopsis with an N-terminal autoinhibitory domain

Science.gov (United States)

Harper, J. F.; Hong, B.; Hwang, I.; Guo, H. Q.; Stoddard, R.; Huang, J. F.; Palmgren, M. G.; Sze, H.; Evans, M. L. (Principal Investigator)

1998-01-01

To study transporters involved in regulating intracellular Ca2+, we isolated a full-length cDNA encoding a Ca2+-ATPase from a model plant, Arabidopsis, and named it ACA2 (Arabidopsis Ca2+-ATPase, isoform 2). ACA2p is most similar to a "plasma membrane-type" Ca2+-ATPase, but is smaller (110 kDa), contains a unique N-terminal domain, and is missing a long C-terminal calmodulin-binding regulatory domain. In addition, ACA2p is localized to an endomembrane system and not the plasma membrane, as shown by aqueous-two phase fractionation of microsomal membranes. ACA2p was expressed in yeast as both a full-length protein (ACA2-1p) and an N-terminal truncation mutant (ACA2-2p; Delta residues 2-80). Only the truncation mutant restored the growth on Ca2+-depleted medium of a yeast mutant defective in both endogenous Ca2+ pumps, PMR1 and PMC1. Although basal Ca2+-ATPase activity of the full-length protein was low, it was stimulated 5-fold by calmodulin (50% activation around 30 nM). In contrast, the truncated pump was fully active and insensitive to calmodulin. A calmodulin-binding sequence was identified within the first 36 residues of the N-terminal domain, as shown by calmodulin gel overlays on fusion proteins. Thus, ACA2 encodes a novel calmodulin-regulated Ca2+-ATPase distinguished by a unique N-terminal regulatory domain and a non-plasma membrane localization.

Antral content, secretion and peripheral metabolism of N-terminal progastrin fragments

DEFF Research Database (Denmark)

Goetze, Jens Peter; Hansen, Carsten Palnaes; Rehfeld, Jens F

2006-01-01

OBJECTIVES: In addition to the acid-stimulatory gastrins, progastrin also release N-terminal fragments. In order to examine the cellular content, secretion and peripheral metabolism of these fragments, we developed an immunoassay specific for the N-terminal sequence of human progastrin. RESULTS......-terminal progastrin fragments. The basal concentration of N-terminal fragments in normal human plasma was almost 30-fold higher than that of the amidated, acid-stimulatory gastrins (286 pmol/l versus 9.8 pmol/l, n=26, P...-35 in circulation was 30 min, and a pig model revealed the kidneys and the vasculature to the head as the primary sites of degradation. CONCLUSION: The cellular and circulatory concentration profiles of N-terminal progastrin fragments differ markedly from those of the acid-stimulatory gastrins. The high basal...

Side chain effect on electronic structure of spin-coated films of [6,6]-phenyl-C61-butyric acid methyl ester and its bis-adduct

International Nuclear Information System (INIS)

Akaike, Kouki; Kanai, Kaname; Ouchi, Yukio; Seki, Kazuhiko

2013-01-01

Highlights: ► Electronic structure of spin-coated films of PCBM and bis-PCBM was investigated. ► Ionization energy and electron affinity of bis-PCBM are smaller than those of PCBM. ► Electron donation from the side chain to C 60 -backbone raises the HOMO and LUMO. ► Open circuit voltages of PCBM-based solar cells relates to electron affinities. - Abstract: We investigated the electronic structure of spin-coated films of two soluble fullerenes; [6,6]-phenyl-C 61 -butyric acid methyl ester (PCBM) and its bis-adduct (bis-PCBM) using ultraviolet photoelectron spectroscopy, inverse photoemission spectroscopy and molecular orbital calculations. The ionization energy and electron affinity of spin-coated films of bis-PCBM were determined to be 6.01 eV and 3.4 eV, respectively. Analysis of electron density suggested the stronger electron donation from the two side chains to fullerene-backbone in a bis-PCBM molecule, compared with PCBM. The electron donation raises the energies of the frontier orbitals of bis-PCBM, which mainly consist of π-orbitals of fullerene-backbone. As a result, the ionization energy and electron affinity of bis-PCBM are smaller than those of PCBM. Moreover, we also concluded that the larger open circuit voltage observed for bis-PCBM based organic photovoltaics was explained by the higher-lying unoccupied molecular orbital of bis-PCBM

N-terminal arginines modulate plasma-membrane localization of Kv7.1/KCNE1 channel complexes.

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Zenawit Girmatsion

Full Text Available BACKGROUND AND OBJECTIVE: The slow delayed rectifier current (I(Ks is important for cardiac action potential termination. The underlying channel is composed of Kv7.1 α-subunits and KCNE1 β-subunits. While most evidence suggests a role of KCNE1 transmembrane domain and C-terminus for the interaction, the N-terminal KCNE1 polymorphism 38G is associated with reduced I(Ks and atrial fibrillation (a human arrhythmia. Structure-function relationship of the KCNE1 N-terminus for I(Ks modulation is poorly understood and was subject of this study. METHODS: We studied N-terminal KCNE1 constructs disrupting structurally important positively charged amino-acids (arginines at positions 32, 33, 36 as well as KCNE1 constructs that modify position 38 including an N-terminal truncation mutation. Experimental procedures included molecular cloning, patch-clamp recording, protein biochemistry, real-time-PCR and confocal microscopy. RESULTS: All KCNE1 constructs physically interacted with Kv7.1. I(Ks resulting from co-expression of Kv7.1 with non-atrial fibrillation '38S' was greater than with any other construct. Ionic currents resulting from co-transfection of a KCNE1 mutant with arginine substitutions ('38G-3xA' were comparable to currents evoked from cells transfected with an N-terminally truncated KCNE1-construct ('Δ1-38'. Western-blots from plasma-membrane preparations and confocal images consistently showed a greater amount of Kv7.1 protein at the plasma-membrane in cells co-transfected with the non-atrial fibrillation KCNE1-38S than with any other construct. CONCLUSIONS: The results of our study indicate that N-terminal arginines in positions 32, 33, 36 of KCNE1 are important for reconstitution of I(Ks. Furthermore, our results hint towards a role of these N-terminal amino-acids in membrane representation of the delayed rectifier channel complex.

μ-Oxalato-bis[(2,2′-bipyridylcopper(II] bis(perchlorate dimethylformamide disolvate monohydrate

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Alexander N. Boyko

2010-09-01

Full Text Available The title compound, [Cu2(C2O4(C10H8N24](ClO42·2C3H7NO·H2O, contains doubly charged centrosymmetric dinuclear oxalato-bridged copper(II complex cations, perchlorate anions, and DMF and water solvate molecules. In the complex cation, the oxalate ligand is coordinated in a bis-bidentate bridging mode to the Cu atoms. Each Cu atom has a distorted tetragonal-bipyramidal environment, being coordinated by two N atoms of the two chelating bipy ligands and two O atoms of the doubly deprotonated oxalate anion. Pairs of perchlorate anions and water molecules are linked into rectangles by O—H...O bonds in which the perchlorate O atoms act as acceptors and the water molecules as donors. Methyl groups of the DMF solvent molecule are disordered over two sites with occupancies of 0.453 (7:0.547 (7, and the water molecule is half-occupied.

Ribonucleocapsid Formation of SARS-COV Through Molecular Action of the N-Terminal Domain of N Protein

Energy Technology Data Exchange (ETDEWEB)

Saikatendu, K.S.; Joseph, J.S.; Subramanian, V.; Neuman, B.W.; Buchmeier, M.J.; Stevens, R.C.; Kuhn, P.; /Scripps Res. Inst.

2007-07-12

Conserved amongst all coronaviruses are four structural proteins, the matrix (M), small envelope (E) and spike (S) that are embedded in the viral membrane and the nucleocapsid phosphoprotein (N), which exists in a ribonucleoprotein complex in their lumen. The N terminal domain of coronaviral N proteins (N-NTD) provides a scaffold for RNA binding while the C-terminal domain (N-CTD) mainly acts as oligomerization modules during assembly. The C-terminus of N protein anchors it to the viral membrane by associating with M protein. We characterized the structures of N-NTD from severe acute respiratory syndrome coronavirus (SARS-CoV) in two crystal forms, at 1.17A (monoclinic) and 1.85 A (cubic) respectively, solved by molecular replacement using the homologous avian infectious bronchitis virus (IBV) structure. Flexible loops in the solution structure of SARS-CoV N-NTD are now shown to be well ordered around the beta-sheet core. The functionally important positively charged beta-hairpin protrudes out of the core and is oriented similar to that in the IBV N-NTD and is involved in crystal packing in the monoclinic form. In the cubic form, the monomers form trimeric units that stack in a helical array. Comparison of crystal packing of SARS-CoV and IBV N-NTDs suggest a common mode of RNA recognition, but probably associate differently in vivo during the formation of the ribonucleoprotein complex. Electrostatic potential distribution on the surface of homology models of related coronaviral N-NTDs hints that they employ different modes of both RNA recognition as well as oligomeric assembly, perhaps explaining why their nucleocapsids have different morphologies.

Crystal structures of bis(phenoxysilicon phthalocyanines: increasing π–π interactions, solubility and disorder and no halogen bonding observed

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Benoît H. Lessard

2016-07-01

Full Text Available We report the syntheses and characterization of three solution-processable phenoxy silicon phthalocyanines (SiPcs, namely bis(3-methylphenoxy(phthalocyaninesilicon [(3MP2-SiPc], C46H30N8O2Si, bis(2-sec-butylphenoxy(phthalocyaninesilicon [(2secBP2-SiPc], C44H24I2N8O2Si, and bis(3-iodophenoxy(phthalocyaninesilicon [(3IP2-SiPc], C52H42N8O2Si. Crystals grown of these compounds were characterized by single-crystal X-ray diffraction and the π–π interactions between the aromatic SiPc cores were studied. It was determined that (3MP2-SiPc has similar interactions to previously reported bis(3,4,5-trifluorophenoxysilicon phthalocyanines [(345 F2-SiPc] with significant π–π interactions between the SiPc groups. (3IP2-SiPc and (2secBP2-SiPc both experienced a parallel stacking of two of the peripheral aromatic groups. In all three cases, the solubility of these molecules was increased by the addition of phenoxy groups while maintaining π–π interactions between the aromatic SiPc groups. The solubility of (2secBP2-SiPc was significantly higher than other bis-phenoxy-SiPcs and this was exemplified by the higher observed disorder within the crystal structure.

Synthesis and photoinduced electron transfer in platinum(II) bis(N-(4-ethynylphenyl)carbazole)bipyridine fullerene complexes.

Science.gov (United States)

Lee, Sai-Ho; Chan, Chris Tsz-Leung; Wong, Keith Man-Chung; Lam, Wai Han; Kwok, Wai-Ming; Yam, Vivian Wing-Wah

2014-12-21

Platinum(ii) bis(N-(4-ethynylphenyl)carbazole)bipyridine fullerene complexes, (Cbz)2-Pt(bpy)-C60 and ((t)BuCbz)2-Pt(bpy)-C60, were synthesized. Their photophysical properties were studied by electronic absorption and emission spectroscopy and the origin of the transitions was supported by computational studies. The electrochemical properties were also studied and the free energies for charge-separation and charge-recombination processes were evaluated. The photoinduced electron transfer reactions in the triads were investigated by femtosecond and nanosecond transient absorption spectroscopy. In dichloromethane, both triads undergo ultrafast charge separation from the (3)MLCT/LLCT excited state within 300 fs to yield their respective triplet charge-separated (CS) states, namely (Cbz)2˙(+)-Pt(bpy)-C60˙(-) and ((t)BuCbz)2˙(+)-Pt(bpy)-C60˙(-), and the CS states would undergo charge recombination to give the (3)C60* state, which subsequently decays to the ground state in 22-28 μs.

N,N,N′,N′,N′′-Pentamethyl-N′′-[2-(trimethylazaniumylethyl]guanidinium bis(tetraphenylborate acetone monosolvate

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Ioannis Tiritiris

2016-02-01

Full Text Available The asymmetric unit of the title solvated salt, C11H28N42+·2C24H20B−·C3H6O, comprises two cations, four tetraphenylborate anions and two acetone molecules. One cation shows an orientational disorder at the CN3 moiety and two sets of N-atom positions were found related by a 60° rotation, with a refined occupancy ratio of 0.935 (1:0.065 (1. The respective nitrogen-bonded –CH2 and –CH3 groups are included in the disorder model. The C—N bond lengths in the central CN3 units of both guanidinium ions range between 1.3329 (17 and 1.364 (16 Å, indicating a degree of double-bond character. The central C atom is bonded to the three N atoms in a nearly ideal trigonal–planar geometry and one positive charge is delocalized in the CN3 plane. The C—N bond lengths in the terminal trimethylammonium groups have values close to a typical single bond, and the second positive charge is localized there. In the crystal, the guanidinium ions are connected by C—H...O hydrogen bonds with the acetone molecules. C—H...π interactions are present between the guanidinium and acetone hydrogen atoms and the phenyl rings of the tetraphenylborate ions, leading to the formation of a two-dimensional supramolecular pattern along the bc plane.

Characterization of Runella slithyformis HD-Pnk, a bifunctional DNA/RNA end-healing enzyme composed of an N-terminal 2',3' -phosphoesterase HD domain and a C-terminal 5' -OH polynucleotide kinase domain.

Science.gov (United States)

Munir, Annum; Shuman, Stewart

2016-11-28

5' and 3' end healing are key steps in nucleic acid break repair in which 5' -OH ends are phosphorylated by a polynucleotide kinase and 3' -PO 4 or 2',3' -cyclic-PO 4 ends are hydrolyzed by a phosphoesterase to generate the 5' -PO 4 and 3' -OH termini required for sealing by classic polynucleotide ligases. End healing and sealing enzymes are present in diverse bacterial taxa, often organized as modular units within a single multifunctional polypeptide or as subunits of a repair complex. Here we identify and characterize Runella slithyformis HD-Pnk as a novel bifunctional end-healing enzyme composed of an N-terminal 2',3' -phosphoesterase HD domain and a C-terminal 5' -OH polynucleotide kinase P-loop domain. HD-Pnk phosphorylates 5' -OH polynucleotides (9-mers or longer) in the presence of magnesium and any NTP donor. HD-Pnk dephosphorylates RNA 2',3' -cyclic phosphate, RNA 3' -phosphate, RNA 2' -phosphate, and DNA 3' -phosphate ends in the presence of a transition metal cofactor, which can be nickel, copper or cobalt. HD-Pnkp homologs are present in genera from eleven bacterial phyla and are often encoded in an operon with a putative ATP-dependent polynucleotide ligase. The present study provides insights to the diversity of nucleic acid repair strategies via the characterization of Runella slithyformis HD-Pnkp as the exemplar of a novel clade of dual 5' and 3' end-healing enzymes that phosphorylate 5' -OH termini and dephosphorylate 2',3' -cyclic-PO 4 , 3' -PO 4 , and 2' -PO 4 ends. The distinctive feature of HD-Pnk is its domain composition: a fusion of an N-terminal HD phosphohydrolase module to a C-terminal P-loop polynucleotide kinase module. Homologs of Runella HD-Pnk with the same domain composition, domain order, and similar polypeptide size are distributed widely among genera from eleven bacterial phyla. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Amino-terminal extension present in the methionine aminopeptidase type 1c of Mycobacterium tuberculosis is indispensible for its activity

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Kumaran Sangaralingam

2011-07-01

Full Text Available Abstract Background Methionine aminopeptidase (MetAP is a ubiquitous enzyme in both prokaryotes and eukaryotes, which catalyzes co-translational removal of N-terminal methionine from elongating polypeptide chains during protein synthesis. It specifically removes the terminal methionine in all organisms, if the penultimate residue is non-bulky and uncharged. The MetAP action for exclusion of N-terminal methionine is mandatory in 50-70% of nascent proteins. Such an activity is required for proper sub cellular localization, additional processing and eventually for the degradation of proteins. Results We cloned genes encoding two such metalloproteases (MtMetAP1a and MtMetAP1c present in Mycobacterium tuberculosis and expressed them as histidine-tagged proteins in Escherichia coli. Although they have different substrate preferences, for Met-Ala-Ser, we found, MtMetAP1c had significantly high enzyme turnover rate as opposed to MtMetAP1a. Circular dichroism spectroscopic studies as well as monitoring of enzyme activity indicated high temperature stability (up to 50°C of MtMetAP1a compared to that of the MtMetAP1c. Modelling of MtMetAP1a based on MtMetAP1c crystal structure revealed the distinct spatial arrangements of identical active site amino acid residues and their mutations affected the enzymatic activities of both the proteins. Strikingly, we observed that 40 amino acid long N-terminal extension of MtMetAP1c, compared to its other family members, contributes towards the activity and stability of this enzyme, which has never been reported for any methionine aminopeptidase. Furthermore, mutational analysis revealed that Val-18 and Pro-19 of MtMetAP1c are crucial for its enzymatic activity. Consistent with this observation, molecular dynamic simulation studies of wild-type and these variants strongly suggest their involvement in maintaining active site conformation of MtMetAP1c. Conclusion Our findings unequivocally emphasized that N-terminal

4-Aminobenzoic acid–1,2-bis(4-pyridylethane (2/1