AtMRP1 gene of Arabidopsis encodes a glutathione S-conjugate pump: isolation and functional definition of a plant ATP-binding cassette transporter gene.

Science.gov (United States)

Lu, Y P; Li, Z S; Rea, P A

1997-07-22

Because plants produce cytotoxic compounds to which they, themselves, are susceptible and are exposed to exogenous toxins (microbial products, allelochemicals, and agrochemicals), cell survival is contingent on mechanisms for detoxifying these agents. One detoxification mechanism is the glutathione S-transferase-catalyzed glutathionation of the toxin, or an activated derivative, and transport of the conjugate out of the cytosol. We show here that a transporter responsible for the removal of glutathione S-conjugates from the cytosol, a specific Mg2+-ATPase, is encoded by the AtMRP1 gene of Arabidopsis thaliana. The sequence of AtMRP1 and the transport capabilities of membranes prepared from yeast cells transformed with plasmid-borne AtMRP1 demonstrate that this gene encodes an ATP-binding cassette transporter competent in the transport of glutathione S-conjugates of xenobiotics and endogenous substances, including herbicides and anthocyanins.

Structure of the Putative 32 kDa Myrosinase Binding Protein from Arabidopsis (At3g16450.1) Determined by SAIL-NMR

Science.gov (United States)

Takeda, Mitsuhiro; Sugimori, Nozomi; Torizawa, Takuya; Terauchi, Tsutomu; Ono, Akira Mei; Yagi, Hirokazu; Yamaguchi, Yoshiki; Kato, Koichi; Ikeya, Teppei; Jee, JunGoo; Güntert, Peter; Aceti, David J.; Markley, John L.; Kainosho, Masatsune

2009-01-01

The product of gene At3g16450.1 from Arabidopsis thaliana is a 32 kDa, 299-residue protein classified as resembling a myrosinase-binding protein (MyroBP). MyroBPs are found in plants as part of a complex with the glucosinolate-degrading enzyme, myrosinase, and are suspected to play a role in myrosinase-dependent defense against pathogens. Many MyroBPs and MyroBP-related proteins are composed of repeated homologous sequences with unknown structure. We report here the three-dimensional structure of the At3g16450.1 protein from Arabidopsis, which consists of two tandem repeats. Because the size of the protein is larger than that amenable to high-throughput analysis by uniformly 13C/15N labeling methods, we used our stereo-array isotope labeling (SAIL) technology to prepare an optimally 2H/13C/15N-labeled sample. NMR data sets collected with the SAIL-protein enabled us to assign 1H, 13C and 15N chemical shifts to 95.5% of all atoms, even at the low concentration (0.2 mM) of the protein product. We collected additional NOESY data and solved the three-dimensional structure with the CYANA software package. The structure, the first for a MyroBP family member, revealed that the At3g16450.1 protein consists of two independent, but similar, lectin-fold domains composed of three β-sheets. PMID:19021763

BIIDXI, the At4g32460 DUF642 gene, is involved in pectin methyl esterase regulation during Arabidopsis thaliana seed germination and plant development.

Science.gov (United States)

Zúñiga-Sánchez, Esther; Soriano, Diana; Martínez-Barajas, Eleazar; Orozco-Segovia, Alma; Gamboa-deBuen, Alicia

2014-12-02

DUF642 proteins constitute a highly conserved family of proteins that are associated with the cell wall and are specific to spermatophytes. Transcriptome studies have suggested that members of this family are involved in seed development and germination processes. Previous in vitro studies have revealed that At4g32460- and At5g11420-encoded proteins interact with the catalytic domain of pectin methyl esterase 3 (AtPME3, which is encoded by At3g14310). PMEs play an important role in plant development, including seed germination. The aim of this study was to evaluate the function of the DUF642 gene At4g32460 during seed germination and plant development and to determine its relation to PME activity regulation. Our results indicated that the DUF642 proteins encoded by At4g32460 and At5g11420 could be positive regulators of PME activity during several developmental processes. Transgenic lines overexpressing these proteins showed increased PME activity during seed germination, and improved seed germination performance. In plants expressing At4g32460 antisense RNA, PME activity was decreased in the leaves, and the siliques were very short and contained no seeds. This phenotype was also present in the SALK_142260 and SALK_054867 lines for At4g32460. Our results suggested that the DUF642 family contributes to the complexity of the methylesterification process by participating in the fine regulation of pectin status during plant development.

Cloning and characterization of the gene encoding IMP dehydrogenase from Arabidopsis thaliana.

Science.gov (United States)

Collart, F R; Osipiuk, J; Trent, J; Olsen, G J; Huberman, E

1996-10-03

We have cloned and characterized the gene encoding inosine monophosphate dehydrogenase (IMPDH) from Arabidopsis thaliana (At). The transcription unit of the At gene spans approximately 1900 bp and specifies a protein of 503 amino acids with a calculated relative molecular mass (M(r)) of 54,190. The gene is comprised of a minimum of four introns and five exons with all donor and acceptor splice sequences conforming to previously proposed consensus sequences. The deduced IMPDH amino-acid sequence from At shows a remarkable similarity to other eukaryotic IMPDH sequences, with a 48% identity to human Type II enzyme. Allowing for conservative substitutions, the enzyme is 69% similar to human Type II IMPDH. The putative active-site sequence of At IMPDH conforms to the IMP dehydrogenase/guanosine monophosphate reductase motif and contains an essential active-site cysteine residue.

Molecular cloning and sequence of cDNA encoding the plasma membrane proton pump (H+-ATPase) of Arabidopsis thaliana

International Nuclear Information System (INIS)

Harper, J.F.; Surowy, T.K.; Sussman, M.R.

1989-01-01

In plants, the transport of solutes across the plasma membrane is driven by a proton pump (H + -ATPase) that produces an electric potential and pH gradient. The authors isolated and sequenced a full-length cDNA clone that encodes this enzyme in Arabidopsis thaliana. The protein predicted from its nucleotide sequence encodes 959 amino acids and has a molecular mass of 104,207 Da. The plant protein shows structural features common to a family of cation-translocating ATPases found in the plasma membrane of prokaryotic and eukaryotic cells, with the greatest overall identity in amino acid sequence (36%) to the H + -ATPase observed in the plasma membrane of fungi. The structure predicted from a hydropathy plant contains at least eight transmembrane segments, with most of the protein (73%) extending into the cytoplasm and only 5% of the residues exposed on the external surface. Unique features of the plant enzyme include diverged sequences at the amino and carboxyl termini as well as greater hydrophilic character in three extracellular loops

An early nodulin-like protein accumulates in the sieve element plasma membrane of Arabidopsis

DEFF Research Database (Denmark)

Khan, Junaid A.; Wang, Qi; Sjölund, Richard D.

2007-01-01

Membrane proteins within the sieve element-companion cell complex have essential roles in the physiological functioning of the phloem. The monoclonal antibody line RS6, selected from hybridomas raised against sieve elements isolated from California shield leaf (Streptanthus tortuosus; Brassicaceae...... was revealed by reverse transcription-PCR of Arabidopsis leaf RNA using degenerate primers to be an early nodulin (ENOD)-like protein that is encoded by the expressed gene At3g20570. Arabidopsis ENOD-like proteins are encoded by a multigene family composed of several types of structurally related phytocyanins...... from the precursor protein, resulting in a mature peptide of approximately 15 kD that is attached to the sieve element plasma membrane via a carboxy-terminal glycosylphosphatidylinositol membrane anchor. Many of the Arabidopsis ENOD-like proteins accumulate in gametophytic tissues, whereas in both...

bHLH106 Integrates Functions of Multiple Genes through Their G-Box to Confer Salt Tolerance on Arabidopsis.

Science.gov (United States)

Ahmad, Aftab; Niwa, Yasuo; Goto, Shingo; Ogawa, Takeshi; Shimizu, Masanori; Suzuki, Akane; Kobayashi, Kyoko; Kobayashi, Hirokazu

2015-01-01

An activation-tagging methodology was applied to dedifferentiated calli of Arabidopsis to identify new genes involved in salt tolerance. This identified salt tolerant callus 8 (stc8) as a gene encoding the basic helix-loop-helix transcription factor bHLH106. bHLH106-knockout (KO) lines were more sensitive to NaCl, KCl, LiCl, ABA, and low temperatures than the wild-type. Back-transformation of the KO line rescued its phenotype, and over-expression (OX) of bHLH106 in differentiated plants exhibited tolerance to NaCl. Green fluorescent protein (GFP) fused with bHLH106 revealed that it was localized to the nucleus. Prepared bHLH106 protein was subjected to electrophoresis mobility shift assays against E-box sequences (5'-CANNTG-3'). The G-box sequence 5'-CACGTG-3' had the strongest interaction with bHLH106. bHLH106-OX lines were transcriptomically analyzed, and resultant up- and down-regulated genes selected on the criterion of presence of a G-box sequence. There were 198 genes positively regulated by bHLH106 and 36 genes negatively regulated; these genes possessed one or more G-box sequences in their promoter regions. Many of these genes are known to be involved in abiotic stress response. It is concluded that bHLH106 locates at a branching point in the abiotic stress response network by interacting directly to the G-box in genes conferring salt tolerance on plants.

Arabidopsis N-MYC DOWNREGULATED-LIKE1, a positive regulator of auxin transport in a G protein-mediated pathway.

Science.gov (United States)

Mudgil, Yashwanti; Uhrig, Joachm F; Zhou, Jiping; Temple, Brenda; Jiang, Kun; Jones, Alan M

2009-11-01

Root architecture results from coordinated cell division and expansion in spatially distinct cells of the root and is established and maintained by gradients of auxin and nutrients such as sugars. Auxin is transported acropetally through the root within the central stele and then, upon reaching the root apex, auxin is transported basipetally through the outer cortical and epidermal cells. The two Gbetagamma dimers of the Arabidopsis thaliana heterotrimeric G protein complex are differentially localized to the central and cortical tissues of the Arabidopsis roots. A null mutation in either the single beta (AGB1) or the two gamma (AGG1 and AGG2) subunits confers phenotypes that disrupt the proper architecture of Arabidopsis roots and are consistent with altered auxin transport. Here, we describe an evolutionarily conserved interaction between AGB1/AGG dimers and a protein designated N-MYC DOWNREGULATED-LIKE1 (NDL1). The Arabidopsis genome encodes two homologs of NDL1 (NDL2 and NDL3), which also interact with AGB1/AGG1 and AGB1/AGG2 dimers. We show that NDL proteins act in a signaling pathway that modulates root auxin transport and auxin gradients in part by affecting the levels of at least two auxin transport facilitators. Reduction of NDL family gene expression and overexpression of NDL1 alter root architecture, auxin transport, and auxin maxima. AGB1, auxin, and sugars are required for NDL1 protein stability in regions of the root where auxin gradients are established; thus, the signaling mechanism contains feedback loops.

Arabidopsis N-MYC DOWNREGULATED-LIKE1, a Positive Regulator of Auxin Transport in a G Protein–Mediated Pathway[W

Science.gov (United States)

Mudgil, Yashwanti; Uhrig, Joachm F.; Zhou, Jiping; Temple, Brenda; Jiang, Kun; Jones, Alan M.

2009-01-01

Root architecture results from coordinated cell division and expansion in spatially distinct cells of the root and is established and maintained by gradients of auxin and nutrients such as sugars. Auxin is transported acropetally through the root within the central stele and then, upon reaching the root apex, auxin is transported basipetally through the outer cortical and epidermal cells. The two Gβγ dimers of the Arabidopsis thaliana heterotrimeric G protein complex are differentially localized to the central and cortical tissues of the Arabidopsis roots. A null mutation in either the single β (AGB1) or the two γ (AGG1 and AGG2) subunits confers phenotypes that disrupt the proper architecture of Arabidopsis roots and are consistent with altered auxin transport. Here, we describe an evolutionarily conserved interaction between AGB1/AGG dimers and a protein designated N-MYC DOWNREGULATED-LIKE1 (NDL1). The Arabidopsis genome encodes two homologs of NDL1 (NDL2 and NDL3), which also interact with AGB1/AGG1 and AGB1/AGG2 dimers. We show that NDL proteins act in a signaling pathway that modulates root auxin transport and auxin gradients in part by affecting the levels of at least two auxin transport facilitators. Reduction of NDL family gene expression and overexpression of NDL1 alter root architecture, auxin transport, and auxin maxima. AGB1, auxin, and sugars are required for NDL1 protein stability in regions of the root where auxin gradients are established; thus, the signaling mechanism contains feedback loops. PMID:19948787

The Arabidopsis thiamin-deficient mutant pale green1 lacks thiamin monophosphate phosphatase of the vitamin B1 biosynthesis pathway.

Science.gov (United States)

Hsieh, Wei-Yu; Liao, Jo-Chien; Wang, Hsin-Tzu; Hung, Tzu-Huan; Tseng, Ching-Chih; Chung, Tsui-Yun; Hsieh, Ming-Hsiun

2017-07-01

Thiamin diphosphate (TPP, vitamin B 1 ) is an essential coenzyme present in all organisms. Animals obtain TPP from their diets, but plants synthesize TPPde novo. We isolated and characterized an Arabidopsis pale green1 (pale1) mutant that contained higher concentrations of thiamin monophosphate (TMP) and less thiamin and TPP than the wild type. Supplementation with thiamin, but not the thiazole and pyrimidine precursors, rescued the mutant phenotype, indicating that the pale1 mutant is a thiamin-deficient mutant. Map-based cloning and whole-genome sequencing revealed that the pale1 mutant has a mutation in At5g32470 encoding a TMP phosphatase of the TPP biosynthesis pathway. We further confirmed that the mutation of At5g32470 is responsible for the mutant phenotypes by complementing the pale1 mutant with constructs overexpressing full-length At5g32470. Most plant TPP biosynthetic enzymes are located in the chloroplasts and cytosol, but At5g32470-GFP localized to the mitochondrion of the root, hypocotyl, mesophyll and guard cells of the 35S:At5g32470-GFP complemented plants. The subcellular localization of a functional TMP phosphatase suggests that the complete vitamin B1 biosynthesis pathway may involve the chloroplasts, mitochondria and cytosol in plants. Analysis of PALE1 promoter-uidA activity revealed that PALE1 is mainly expressed in vascular tissues of Arabidopsis seedlings. Quantitative RT-PCR analysis of TPP biosynthesis genes and genes encoding the TPP-dependent enzymes pyruvate dehydrogenase, α-ketoglutarate dehydrogenase and transketolase revealed that the transcript levels of these genes were upregulated in the pale1 mutant. These results suggest that endogenous levels of TPP may affect the expression of genes involved in TPP biosynthesis and TPP-dependent enzymes. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

AtALMT1, which encodes a malate transporter, is identified as one of several genes critical for aluminum tolerance in Arabidopsis

OpenAIRE

Hoekenga, Owen A.; Maron, Lyza G.; Piñeros, Miguel A.; Cançado, Geraldo M. A.; Shaff, Jon; Kobayashi, Yuriko; Ryan, Peter R.; Dong, Bei; Delhaize, Emmanuel; Sasaki, Takayuki; Matsumoto, Hideaki; Yamamoto, Yoko; Koyama, Hiroyuki; Kochian, Leon V.

2006-01-01

Aluminum (Al) tolerance in Arabidopsis is a genetically complex trait, yet it is mediated by a single physiological mechanism based on Al-activated root malate efflux. We investigated a possible molecular determinant for Al tolerance involving a homolog of the wheat Al-activated malate transporter, ALMT1. This gene, named AtALMT1 (At1g08430), was the best candidate from the 14-memberAtALMT family to be involved with Al tolerance based on expression patterns and genomic location. Physiological...

AtFH1 formin mutation affects actin filament and microtubule dynamics in Arabidopsis thaliana

Czech Academy of Sciences Publication Activity Database

Rosero, A.; Žárský, Viktor; Cvrčková, F.

2013-01-01

Roč. 64, č. 2 (2013), s. 585-597 ISSN 0022-0957 R&D Projects: GA ČR GAP305/10/0433 Institutional research plan: CEZ:AV0Z50380511 Keywords : Actin * Arabidopsis * At5g25500 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.794, year: 2013

The Arabidopsis GASA10 gene encodes a cell wall protein strongly expressed in developing anthers and seeds.

Science.gov (United States)

Trapalis, Menelaos; Li, Song Feng; Parish, Roger W

2017-07-01

The Arabidopsis GASA10 gene encodes a GAST1-like (Gibberellic Acid-Stimulated) protein. Reporter gene analysis identified consistent expression in anthers and seeds. In anthers expression was developmentally regulated, first appearing at stage 7 of anther development and reaching a maximum at stage 11. Strongest expression was in the tapetum and developing microspores. GASA10 expression also occurred throughout the seed and in root vasculature. GASA10 was shown to be transported to the cell wall. Using GASA1 and GASA6 as positive controls, gibberellic acid was found not to induce GASA10 expression in Arabidopsis suspension cells. Overexpression of GASA10 (35S promoter-driven) resulted in a reduction in silique elongation. GASA10 shares structural similarities to the antimicrobial peptide snakin1, however, purified GASA10 failed to influence the growth of a variety of bacterial and fungal species tested. We propose cell wall associated GASA proteins are involved in regulating the hydroxyl radical levels at specific sites in the cell wall to facilitate wall growth (regulating cell wall elongation). Copyright © 2017 Elsevier B.V. All rights reserved.

Membrane-localized extra-large G proteins and Gbg of the heterotrimeric G proteins form functional complexes engaged in plant immunity in Arabidopsis.

Science.gov (United States)

Maruta, Natsumi; Trusov, Yuri; Brenya, Eric; Parekh, Urvi; Botella, José Ramón

2015-03-01

In animals, heterotrimeric G proteins, comprising Ga, Gb, and Gg subunits, are molecular switches whose function tightly depends on Ga and Gbg interaction. Intriguingly, in Arabidopsis (Arabidopsis thaliana), multiple defense responses involve Gbg, but not Ga. We report here that the Gbg dimer directly partners with extra-large G proteins (XLGs) to mediate plant immunity. Arabidopsis mutants deficient in XLGs, Gb, and Gg are similarly compromised in several pathogen defense responses, including disease development and production of reactive oxygen species. Genetic analysis of double, triple, and quadruple mutants confirmed that XLGs and Gbg functionally interact in the same defense signaling pathways. In addition, mutations in XLG2 suppressed the seedling lethal and cell death phenotypes of BRASSINOSTEROID INSENSITIVE1-associated receptor kinase1-interacting receptor-like kinase1 mutants in an identical way as reported for Arabidopsis Gb-deficient mutants. Yeast (Saccharomyces cerevisiae) three-hybrid and bimolecular fluorescent complementation assays revealed that XLG2 physically interacts with all three possible Gbg dimers at the plasma membrane. Phylogenetic analysis indicated a close relationship between XLGs and plant Ga subunits, placing the divergence point at the dawn of land plant evolution. Based on these findings, we conclude that XLGs form functional complexes with Gbg dimers, although the mechanism of action of these complexes, including activation/deactivation, must be radically different form the one used by the canonical Ga subunit and are not likely to share the same receptors. Accordingly, XLGs expand the repertoire of heterotrimeric G proteins in plants and reveal a higher level of diversity in heterotrimeric G protein signaling.

G2 Checkpoint Responses in Arabidopsis

Energy Technology Data Exchange (ETDEWEB)

Britt, Anne [Univ. of California, Davis, CA (United States)

2013-03-18

This project focused on the mechanism and biological significance of the G2 arrest response to replication stress in plants. We employed both forward and reverse genetic approaches to identify genes required for this response. A total of 3 different postdocs, 5 undergraduates, and 2 graduate students participated in the project. We identified several genes required for damage response in plants, including homologs of genes previously identified in animals (ATM and ATR), novel, a plant-specific genes (SOG1) and a gene known in animals but previously thought to be missing from the Arabidopsis genome (ATRIP). We characterized the transcriptome of gamma-irradiated plants, and found that plants, unlike animals, express a robust transcriptional response to damage, involving genes that regulate the cell cycle and DNA metabolism. This response requires both ATM and the transcription factor SOG1. We found that both ATM and ATR play a role in meiosis in plants. We also found that plants have a cell-type-specific programmed cell death response to ionizing radiation and UV light, and that this response requires ATR, ATM, and SOG1. These results were published in a series of 5 papers.

Molecular cloning and characterization of RGA1 encoding a G protein alpha subunit from rice (Oryza sativa L. IR-36).

Science.gov (United States)

Seo, H S; Kim, H Y; Jeong, J Y; Lee, S Y; Cho, M J; Bahk, J D

1995-03-01

A cDNA clone, RGA1, was isolated by using a GPA1 cDNA clone of Arabidopsis thaliana G protein alpha subunit as a probe from a rice (Oryza sativa L. IR-36) seedling cDNA library from roots and leaves. Sequence analysis of genomic clone reveals that the RGA1 gene has 14 exons and 13 introns, and encodes a polypeptide of 380 amino acid residues with a calculated molecular weight of 44.5 kDa. The encoded protein exhibits a considerable degree of amino acid sequence similarity to all the other known G protein alpha subunits. A putative TATA sequence (ATATGA), a potential CAAT box sequence (AGCAATAC), and a cis-acting element, CCACGTGG (ABRE), known to be involved in ABA induction are found in the promoter region. The RGA1 protein contains all the consensus regions of G protein alpha subunits except the cysteine residue near the C-terminus for ADP-ribosylation by pertussis toxin. The RGA1 polypeptide expressed in Escherichia coli was, however, ADP-ribosylated by 10 microM [adenylate-32P] NAD and activated cholera toxin. Southern analysis indicates that there are no other genes similar to the RGA1 gene in the rice genome. Northern analysis reveals that the RGA1 mRNA is 1.85 kb long and expressed in vegetative tissues, including leaves and roots, and that its expression is regulated by light.

The TCP4 transcription factor of Arabidopsis blocks cell division in yeast at G1 → S transition

International Nuclear Information System (INIS)

Aggarwal, Pooja; Padmanabhan, Bhavna; Bhat, Abhay; Sarvepalli, Kavitha; Sadhale, Parag P.; Nath, Utpal

2011-01-01

Highlights: → TCP4 is a class II TCP transcription factor, that represses cell division in Arabidopsis. → TCP4 expression in yeast retards cell division by blocking G1 → S transition. → Genome-wide expression studies and Western analysis reveals stabilization of cell cycle inhibitor Sic1, as possible mechanism. -- Abstract: The TCP transcription factors control important aspects of plant development. Members of class I TCP proteins promote cell cycle by regulating genes directly involved in cell proliferation. In contrast, members of class II TCP proteins repress cell division. While it has been postulated that class II proteins induce differentiation signal, their exact role on cell cycle has not been studied. Here, we report that TCP4, a class II TCP protein from Arabidopsis that repress cell proliferation in developing leaves, inhibits cell division by blocking G1 → S transition in budding yeast. Cells expressing TCP4 protein with increased transcriptional activity fail to progress beyond G1 phase. By analyzing global transcriptional status of these cells, we show that expression of a number of cell cycle genes is altered. The possible mechanism of G1 → S arrest is discussed.

Molecular and physiological characterization of AtHIGD1 in Arabidopsis.

Science.gov (United States)

Hwang, Soong-Taek; Li, Huiling; Alavilli, Hemasundar; Lee, Byeong-Ha; Choi, Dongsu

2017-06-10

Flooding is a principal stress that limits plant productivity. The sensing of low oxygen levels (hypoxia) plays a critical role in the signaling pathway that functions in plants in flooded environments. In this study, to investigate hypoxia response mechanisms in Arabidopsis, we identified three hypoxia-related genes and subjected one of these genes, Arabidopsis thaliana HYPOXIA-INDUCED GENE DOMAIN 1 (AtHIGD1), to molecular characterization including gene expression analysis and intracellular localization of the encoded protein. AtHIGD1 was expressed in various organs but was preferentially expressed in developing siliques. Confocal microscopy of transgenic plants harboring eGFP-tagged AtHIGD1 indicated that AtHIGD1 is localized to mitochondria. Importantly, plants overexpressing AtHIGD1 exhibited increased resistance to hypoxia compared to wild type. Our results represent the first report of a biological function for an HIGD protein in plants and indicate that AtHIGD1 is a mitochondrial protein that plays an active role in mitigating the effects of hypoxia on plants. Copyright © 2017 Elsevier Inc. All rights reserved.

CLE peptide-encoding gene families in Medicago truncatula and Lotus japonicus, compared with those of soybean, common bean and Arabidopsis

DEFF Research Database (Denmark)

Hastwell, April H; de Bang, Thomas Christian; Gresshoff, Peter M

2017-01-01

these complete CLE peptide-encoding gene families with those of fellow legumes, Glycine max and Phaseolus vulgaris, in addition to the model plant Arabidopsis thaliana. This approach provided insight into the evolution of CLE peptide families and enabled us to establish putative M. truncatula and L. japonicus...

Arabidopsis CDS blastp result: AK242601 [KOME

Lifescience Database Archive (English)

Full Text Available AK242601 J090014G03 At4g23990.1 68417.m03448 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 5e-25 ...

Arabidopsis CDS blastp result: AK242601 [KOME

Lifescience Database Archive (English)

Full Text Available AK242601 J090014G03 At2g32530.1 68415.m03974 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 5e-48 ...

Arabidopsis CDS blastp result: AK241438 [KOME

Lifescience Database Archive (English)

Full Text Available AK241438 J065162G03 At4g32040.1 68417.m04561 homeobox protein knotted-1 like 5 (KNAT5) / home...odomain containing protein 1 (H1) identical to homeobox protein knotted-1 like 5 (KNAT5) SP:P48002 from [Arabidopsis thaliana] 4e-98 ...

Genes encoding calmodulin-binding proteins in the Arabidopsis genome

Science.gov (United States)

Reddy, Vaka S.; Ali, Gul S.; Reddy, Anireddy S N.

2002-01-01

Analysis of the recently completed Arabidopsis genome sequence indicates that approximately 31% of the predicted genes could not be assigned to functional categories, as they do not show any sequence similarity with proteins of known function from other organisms. Calmodulin (CaM), a ubiquitous and multifunctional Ca(2+) sensor, interacts with a wide variety of cellular proteins and modulates their activity/function in regulating diverse cellular processes. However, the primary amino acid sequence of the CaM-binding domain in different CaM-binding proteins (CBPs) is not conserved. One way to identify most of the CBPs in the Arabidopsis genome is by protein-protein interaction-based screening of expression libraries with CaM. Here, using a mixture of radiolabeled CaM isoforms from Arabidopsis, we screened several expression libraries prepared from flower meristem, seedlings, or tissues treated with hormones, an elicitor, or a pathogen. Sequence analysis of 77 positive clones that interact with CaM in a Ca(2+)-dependent manner revealed 20 CBPs, including 14 previously unknown CBPs. In addition, by searching the Arabidopsis genome sequence with the newly identified and known plant or animal CBPs, we identified a total of 27 CBPs. Among these, 16 CBPs are represented by families with 2-20 members in each family. Gene expression analysis revealed that CBPs and CBP paralogs are expressed differentially. Our data suggest that Arabidopsis has a large number of CBPs including several plant-specific ones. Although CaM is highly conserved between plants and animals, only a few CBPs are common to both plants and animals. Analysis of Arabidopsis CBPs revealed the presence of a variety of interesting domains. Our analyses identified several hypothetical proteins in the Arabidopsis genome as CaM targets, suggesting their involvement in Ca(2+)-mediated signaling networks.

Does low stomatal conductance or photosynthetic capacity enhance growth at elevated CO2 in Arabidopsis?

Science.gov (United States)

Easlon, Hsien Ming; Carlisle, Eli; McKay, John K; Bloom, Arnold J

2015-03-01

The objective of this study was to determine if low stomatal conductance (g) increases growth, nitrate (NO3 (-)) assimilation, and nitrogen (N) utilization at elevated CO2 concentration. Four Arabidopsis (Arabidopsis thaliana) near isogenic lines (NILs) differing in g were grown at ambient and elevated CO2 concentration under low and high NO3 (-) supply as the sole source of N. Although g varied by 32% among NILs at elevated CO2, leaf intercellular CO2 concentration varied by only 4% and genotype had no effect on shoot NO3 (-) concentration in any treatment. Low-g NILs showed the greatest CO2 growth increase under N limitation but had the lowest CO2 growth enhancement under N-sufficient conditions. NILs with the highest and lowest g had similar rates of shoot NO3 (-) assimilation following N deprivation at elevated CO2 concentration. After 5 d of N deprivation, the lowest g NIL had 27% lower maximum carboxylation rate and 23% lower photosynthetic electron transport compared with the highest g NIL. These results suggest that increased growth of low-g NILs under N limitation most likely resulted from more conservative N investment in photosynthetic biochemistry rather than from low g. © 2015 American Society of Plant Biologists. All Rights Reserved.

Expression pattern of two paralogs encoding cinnamyl alcohol dehydrogenases in Arabidopsis. Isolation and characterization of the corresponding mutants.

Science.gov (United States)

Sibout, Richard; Eudes, Aymerick; Pollet, Brigitte; Goujon, Thomas; Mila, Isabelle; Granier, Fabienne; Séguin, Armand; Lapierre, Catherine; Jouanin, Lise

2003-06-01

Studying Arabidopsis mutants of the phenylpropanoid pathway has unraveled several biosynthetic steps of monolignol synthesis. Most of the genes leading to monolignol synthesis have been characterized recently in this herbaceous plant, except those encoding cinnamyl alcohol dehydrogenase (CAD). We have used the complete sequencing of the Arabidopsis genome to highlight a new view of the complete CAD gene family. Among nine AtCAD genes, we have identified the two distinct paralogs AtCAD-C and AtCAD-D, which share 75% identity and are likely to be involved in lignin biosynthesis in other plants. Northern, semiquantitative restriction fragment-length polymorphism-reverse transcriptase-polymerase chain reaction and western analysis revealed that AtCAD-C and AtCAD-D mRNA and protein ratios were organ dependent. Promoter activities of both genes are high in fibers and in xylem bundles. However, AtCAD-C displayed a larger range of sites of expression than AtCAD-D. Arabidopsis null mutants (Atcad-D and Atcad-C) corresponding to both genes were isolated. CAD activities were drastically reduced in both mutants, with a higher impact on sinapyl alcohol dehydrogenase activity (6% and 38% of residual sinapyl alcohol dehydrogenase activities for Atcad-D and Atcad-C, respectively). Only Atcad-D showed a slight reduction in Klason lignin content and displayed modifications of lignin structure with a significant reduced proportion of conventional S lignin units in both stems and roots, together with the incorporation of sinapaldehyde structures ether linked at Cbeta. These results argue for a substantial role of AtCAD-D in lignification, and more specifically in the biosynthesis of sinapyl alcohol, the precursor of S lignin units.

Efficient Plastid Transformation in Arabidopsis.

Science.gov (United States)

Yu, Qiguo; Lutz, Kerry Ann; Maliga, Pal

2017-09-01

Plastid transformation is routine in tobacco ( Nicotiana tabacum ) but 100-fold less frequent in Arabidopsis ( Arabidopsis thaliana ), preventing its use in plastid biology. A recent study revealed that null mutations in ACC2 , encoding a plastid-targeted acetyl-coenzyme A carboxylase, cause hypersensitivity to spectinomycin. We hypothesized that plastid transformation efficiency should increase in the acc2 background, because when ACC2 is absent, fatty acid biosynthesis becomes dependent on translation of the plastid-encoded ACC β-carboxylase subunit. We bombarded ACC2 -defective Arabidopsis leaves with a vector carrying a selectable spectinomycin resistance ( aadA ) gene and gfp , encoding the green fluorescence protein GFP. Spectinomycin-resistant clones were identified as green cell clusters on a spectinomycin medium. Plastid transformation was confirmed by GFP accumulation from the second open reading frame of a polycistronic messenger RNA, which would not be translated in the cytoplasm. We obtained one to two plastid transformation events per bombarded sample in spectinomycin-hypersensitive Slavice and Columbia acc2 knockout backgrounds, an approximately 100-fold enhanced plastid transformation frequency. Slavice and Columbia are accessions in which plant regeneration is uncharacterized or difficult to obtain. A practical system for Arabidopsis plastid transformation will be obtained by creating an ACC2 null background in a regenerable Arabidopsis accession. The recognition that the duplicated ACCase in Arabidopsis is an impediment to plastid transformation provides a rational template to implement plastid transformation in related recalcitrant crops. © 2017 American Society of Plant Biologists. All Rights Reserved.

Mutations in the Arabidopsis Lst8 and Raptor genes encoding partners of the TOR complex, or inhibition of TOR activity decrease abscisic acid (ABA) synthesis.

Science.gov (United States)

Kravchenko, Alena; Citerne, Sylvie; Jéhanno, Isabelle; Bersimbaev, Rakhmetkazhi I; Veit, Bruce; Meyer, Christian; Leprince, Anne-Sophie

2015-11-27

The Target of Rapamycin (TOR) kinase regulates essential processes in plant growth and development by modulation of metabolism and translation in response to environmental signals. In this study, we show that abscisic acid (ABA) metabolism is also regulated by the TOR kinase. Indeed ABA hormone level strongly decreases in Lst8-1 and Raptor3g mutant lines as well as in wild-type (WT) Arabidopsis plants treated with AZD-8055, a TOR inhibitor. However the growth and germination of these lines are more sensitive to exogenous ABA. The diminished ABA hormone accumulation is correlated with lower transcript levels of ZEP, NCED3 and AAO3 biosynthetic enzymes, and higher transcript amount of the CYP707A2 gene encoding a key-enzyme in abscisic acid catabolism. These results suggest that the TOR signaling pathway is implicated in the regulation of ABA accumulation in Arabidopsis. Copyright © 2015 Elsevier Inc. All rights reserved.

Alternative splicing affects the targeting sequence of peroxisome proteins in Arabidopsis.

Science.gov (United States)

An, Chuanjing; Gao, Yuefang; Li, Jinyu; Liu, Xiaomin; Gao, Fuli; Gao, Hongbo

2017-07-01

A systematic analysis of the Arabidopsis genome in combination with localization experiments indicates that alternative splicing affects the peroxisomal targeting sequence of at least 71 genes in Arabidopsis. Peroxisomes are ubiquitous eukaryotic cellular organelles that play a key role in diverse metabolic functions. All peroxisome proteins are encoded by nuclear genes and target to peroxisomes mainly through two types of targeting signals: peroxisomal targeting signal type 1 (PTS1) and PTS2. Alternative splicing (AS) is a process occurring in all eukaryotes by which a single pre-mRNA can generate multiple mRNA variants, often encoding proteins with functional differences. However, the effects of AS on the PTS1 or PTS2 and the targeting of the protein were rarely studied, especially in plants. Here, we systematically analyzed the genome of Arabidopsis, and found that the C-terminal targeting sequence PTS1 of 66 genes and the N-terminal targeting sequence PTS2 of 5 genes are affected by AS. Experimental determination of the targeting of selected protein isoforms further demonstrated that AS at both the 5' and 3' region of a gene can affect the inclusion of PTS2 and PTS1, respectively. This work underscores the importance of AS on the global regulation of peroxisome protein targeting.

A mutation in the Arabidopsis HYL1 gene encoding a dsRNA binding protein affects responses to abscisic acid, auxin, and cytokinin

Science.gov (United States)

Lu, C.; Fedoroff, N.

2000-01-01

Both physiological and genetic evidence indicate interconnections among plant responses to different hormones. We describe a pleiotropic recessive Arabidopsis transposon insertion mutation, designated hyponastic leaves (hyl1), that alters the plant's responses to several hormones. The mutant is characterized by shorter stature, delayed flowering, leaf hyponasty, reduced fertility, decreased rate of root growth, and an altered root gravitropic response. It also exhibits less sensitivity to auxin and cytokinin and hypersensitivity to abscisic acid (ABA). The auxin transport inhibitor 2,3,5-triiodobenzoic acid normalizes the mutant phenotype somewhat, whereas another auxin transport inhibitor, N-(1-naph-thyl)phthalamic acid, exacerbates the phenotype. The gene, designated HYL1, encodes a 419-amino acid protein that contains two double-stranded RNA (dsRNA) binding motifs, a nuclear localization motif, and a C-terminal repeat structure suggestive of a protein-protein interaction domain. We present evidence that the HYL1 gene is ABA-regulated and encodes a nuclear dsRNA binding protein. We hypothesize that the HYL1 protein is a regulatory protein functioning at the transcriptional or post-transcriptional level.

Dioxygenase-encoding AtDAO1 gene controls IAA oxidation and homeostasis in Arabidopsis

Czech Academy of Sciences Publication Activity Database

Porco, S.; Pěnčík, Aleš; Rashed, A.; Voss, U.; Casanova-Saez, R.; Bishopp, A.; Golebiowska, A.; Bhosale, R.; Swarup, R.; Swarup, K.; Peňáková, Pavlína; Novák, Ondřej; Staswick, P.; Hedden, P.; Phillips, A.; Vissenberg, K.; Bennett, M.J.

2016-01-01

Roč. 113, č. 39 (2016), s. 11016-11021 ISSN 0027-8424 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : Arabidopsis thaliana * IAA degradation * oxidase Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 9.661, year: 2016

Identification of a Xylogalacturonan Xylosyltransferase Involved in Pectin Biosynthesis in Arabidopsis

Energy Technology Data Exchange (ETDEWEB)

Pauly, Markus; Sorensen, Susanne Oxenboll; Harholt, Jesper; Geshi, Naomi; Sakuragi, Yumiko; Moller, Isabel; Zandleven, Joris; Bernal, Adriana J.; Jensen, Niels Bjerg; Sorensen, Charlotte; Jensen, Jacob K.; Beldman, Gerrit; Willats, William G.T.; Scheller, Henrik

2009-08-19

Xylogalacturonan (XGA) is a class of pectic polysaccharide found in plant cell walls. The Arabidopsis thaliana locus At5g33290 encodes a predicted Type II membrane protein, and insertion mutants of the At5g33290 locus had decreased cell wall xylose. Immunological studies, enzymatic extraction of polysaccharides, monosaccharide linkage analysis, and oligosaccharide mass profiling were employed to identify the affected cell wall polymer. Pectic XGA was reduced to much lower levels in mutant than in wild-type leaves, indicating a role of At5g33290 in XGA biosynthesis. The mutated gene was designated xylogalacturonan deficient1 (xgd1). Transformation of the xgd1-1 mutant with the wild-type gene restored XGA to wild-type levels. XGD1 protein heterologously expressed in Nicotiana benthamiana catalyzed the transfer of xylose from UDP-xylose onto oligogalacturonides and endogenous acceptors. The products formed could be hydrolyzed with an XGA-specific hydrolase. These results confirm that the XGD1 protein is a XGA xylosyltransferase. The protein was shown by expression of a fluorescent fusion protein in N. benthamiana to be localized in the Golgi vesicles as expected for a glycosyltransferase involved in pectin biosynthesis.

Genome-wide comparative analysis of NBS-encoding genes between Brassica species and Arabidopsis thaliana.

Science.gov (United States)

Yu, Jingyin; Tehrim, Sadia; Zhang, Fengqi; Tong, Chaobo; Huang, Junyan; Cheng, Xiaohui; Dong, Caihua; Zhou, Yanqiu; Qin, Rui; Hua, Wei; Liu, Shengyi

2014-01-03

Plant disease resistance (R) genes with the nucleotide binding site (NBS) play an important role in offering resistance to pathogens. The availability of complete genome sequences of Brassica oleracea and Brassica rapa provides an important opportunity for researchers to identify and characterize NBS-encoding R genes in Brassica species and to compare with analogues in Arabidopsis thaliana based on a comparative genomics approach. However, little is known about the evolutionary fate of NBS-encoding genes in the Brassica lineage after split from A. thaliana. Here we present genome-wide analysis of NBS-encoding genes in B. oleracea, B. rapa and A. thaliana. Through the employment of HMM search and manual curation, we identified 157, 206 and 167 NBS-encoding genes in B. oleracea, B. rapa and A. thaliana genomes, respectively. Phylogenetic analysis among 3 species classified NBS-encoding genes into 6 subgroups. Tandem duplication and whole genome triplication (WGT) analyses revealed that after WGT of the Brassica ancestor, NBS-encoding homologous gene pairs on triplicated regions in Brassica ancestor were deleted or lost quickly, but NBS-encoding genes in Brassica species experienced species-specific gene amplification by tandem duplication after divergence of B. rapa and B. oleracea. Expression profiling of NBS-encoding orthologous gene pairs indicated the differential expression pattern of retained orthologous gene copies in B. oleracea and B. rapa. Furthermore, evolutionary analysis of CNL type NBS-encoding orthologous gene pairs among 3 species suggested that orthologous genes in B. rapa species have undergone stronger negative selection than those in B .oleracea species. But for TNL type, there are no significant differences in the orthologous gene pairs between the two species. This study is first identification and characterization of NBS-encoding genes in B. rapa and B. oleracea based on whole genome sequences. Through tandem duplication and whole genome

Analysis of fast neutron-generated mutants at the Arabidopsis thaliana HY4 locus

International Nuclear Information System (INIS)

Bruggemann, E.; Handwerger, K.; Essex, C.; Storz, G.

1996-01-01

Ionizing radiation is expected to produce mutants with deletions or other chromosomal rearrangements. These mutants are useful for a variety of purposes, such as creating null alleles and cloning genes whose existence is known only from their mutant phenotype; however, only a few mutations generated by ionizing radiation have been characterized at the molecular level in Arabidopsis thaliana. Twenty fast neutron-generated alleles of the Arabidopsis HY4 locus, which encodes a blue light receptor, CRY1, were isolated and characterized. Nine of the mutant alleles displayed normal genetic behavior. The other 11 mutant alleles were poorly transmitted through the male gametophyte and were lethal in homozygous plants. Southern blot analysis demonstrated that alleles of the first group generally contain small or moderate-sized deletions at HY4, while alleles of the second group contain large deletions at this locus. These results demonstrate that fast neutrons can produce a range of deletions at a single locus in Arabidopsis. Many of these deletions would be suitable for cloning by genomic subtraction or representational difference analysis. The results also suggest the presence of an essential locus adjacent to HY4. (author)

Arabidopsis thaliana GYRB3 does not encode a DNA gyrase subunit.

Directory of Open Access Journals (Sweden)

Katherine M Evans-Roberts

2010-03-01

Full Text Available DNA topoisomerases are enzymes that control the topology of DNA in all cells. DNA gyrase is unique among the topoisomerases in that it is the only enzyme that can actively supercoil DNA using the free energy of ATP hydrolysis. Until recently gyrase was thought to be unique to bacteria, but has now been discovered in plants. The genome of the model plant, Arabidopsis thaliana, is predicted to encode four gyrase subunits: AtGyrA, AtGyrB1, AtGyrB2 and AtGyrB3.We found, contrary to previous data, that AtGyrB3 is not essential to the survival of A. thaliana. Bioinformatic analysis suggests AtGyrB3 is considerably shorter than other gyrase B subunits, lacking part of the ATPase domain and other key motifs found in all type II topoisomerases; but it does contain a putative DNA-binding domain. Partially purified AtGyrB3 cannot bind E. coli GyrA or support supercoiling. AtGyrB3 cannot complement an E. coli gyrB temperature-sensitive strain, whereas AtGyrB2 can. Yeast two-hybrid analysis suggests that AtGyrB3 cannot bind to AtGyrA or form a dimer.These data strongly suggest that AtGyrB3 is not a gyrase subunit but has another unknown function. One possibility is that it is a nuclear protein with a role in meiosis in pollen.

Expression Pattern of Two Paralogs Encoding Cinnamyl Alcohol Dehydrogenases in Arabidopsis. Isolation and Characterization of the Corresponding Mutants1

Science.gov (United States)

Sibout, Richard; Eudes, Aymerick; Pollet, Brigitte; Goujon, Thomas; Mila, Isabelle; Granier, Fabienne; Séguin, Armand; Lapierre, Catherine; Jouanin, Lise

2003-01-01

Studying Arabidopsis mutants of the phenylpropanoid pathway has unraveled several biosynthetic steps of monolignol synthesis. Most of the genes leading to monolignol synthesis have been characterized recently in this herbaceous plant, except those encoding cinnamyl alcohol dehydrogenase (CAD). We have used the complete sequencing of the Arabidopsis genome to highlight a new view of the complete CAD gene family. Among nine AtCAD genes, we have identified the two distinct paralogs AtCAD-C and AtCAD-D, which share 75% identity and are likely to be involved in lignin biosynthesis in other plants. Northern, semiquantitative restriction fragment-length polymorphism-reverse transcriptase-polymerase chain reaction and western analysis revealed that AtCAD-C and AtCAD-D mRNA and protein ratios were organ dependent. Promoter activities of both genes are high in fibers and in xylem bundles. However, AtCAD-C displayed a larger range of sites of expression than AtCAD-D. Arabidopsis null mutants (Atcad-D and Atcad-C) corresponding to both genes were isolated. CAD activities were drastically reduced in both mutants, with a higher impact on sinapyl alcohol dehydrogenase activity (6% and 38% of residual sinapyl alcohol dehydrogenase activities for Atcad-D and Atcad-C, respectively). Only Atcad-D showed a slight reduction in Klason lignin content and displayed modifications of lignin structure with a significant reduced proportion of conventional S lignin units in both stems and roots, together with the incorporation of sinapaldehyde structures ether linked at Cβ. These results argue for a substantial role of AtCAD-D in lignification, and more specifically in the biosynthesis of sinapyl alcohol, the precursor of S lignin units. PMID:12805615

Genome-wide identification and comparative analysis of squamosa-promoter binding proteins (sbp) transcription factor family in gossypium raimondii and arabidopsis thaliana

International Nuclear Information System (INIS)

Ali, M.A.; Alia, K.B.; Atif, R.M.; Rasulj, I.; Nadeem, H.U.; Shahid, A.; Azeem, F

2017-01-01

SQUAMOSA-Promoter Binding Proteins (SBP) are class of transcription factors that play vital role in regulation of plant tissue growth and development. The genes encoding these proteins have not yet been identified in diploid cotton. Thus here, a comprehensive genome wide analysis of SBP genes/proteins was carried out to identify the genes encoding SBP proteins in Gossypium raimondii and Arabidopsis thaliana. We identified 17 SBP genes from Arabidopsis thaliana genome and 30 SBP genes from Gossypium raimondii. Chromosome localization studies revealed the uneven distribution of SBP encoding genes both in the genomes of A. thaliana and G. raimondii. In cotton, five SBP genes were located on chromosome no. 2, while no gene was found on chromosome 9. In A. thaliana, maximum seven SBP genes were identified on chromosome 9, while chromosome 4 did not have any SBP gene. Thus, the SBP gene family might have expanded as a result of segmental as well as tandem duplications in these species. The comparative phylogenetic analysis of Arabidopsis and cotton SBPs revealed the presence of eight groups. The gene structure analysis of SBP encoding genes revealed the presence of one to eleven inrons in both Arabidopsis and G. raimondii. The proteins sharing the same phyletic group mostly demonstrated the similar intron-exon occurrence pattern; and share the common conserved domains. The SBP DNA-binding domain shared 24 absolutely conserved residues in Arabidopsis. The present study can serve as a base for the functional characterization of SBP gene family in Gossypium raimondii. (author)

mCSF1, a nucleus-encoded CRM protein required for the processing of many mitochondrial introns, is involved in the biogenesis of respiratory complexes I and IV in Arabidopsis.

Science.gov (United States)

Zmudjak, Michal; Colas des Francs-Small, Catherine; Keren, Ido; Shaya, Felix; Belausov, Eduard; Small, Ian; Ostersetzer-Biran, Oren

2013-07-01

The coding regions of many mitochondrial genes in plants are interrupted by intervening sequences that are classified as group II introns. Their splicing is essential for the expression of the genes they interrupt and hence for respiratory function, and is facilitated by various protein cofactors. Despite the importance of these cofactors, only a few of them have been characterized. CRS1-YhbY domain (CRM) is a recently recognized RNA-binding domain that is present in several characterized splicing factors in plant chloroplasts. The Arabidopsis genome encodes 16 CRM proteins, but these are largely uncharacterized. Here, we analyzed the intracellular location of one of these hypothetical proteins in Arabidopsis, mitochondrial CAF-like splicing factor 1 (mCSF1; At4 g31010), and analyzed the growth phenotypes and organellar activities associated with mcsf1 mutants in plants. Our data indicated that mCSF1 resides within mitochondria and its functions are essential during embryogenesis. Mutant plants with reduced mCSF1 displayed inhibited germination and retarded growth phenotypes that were tightly associated with reduced complex I and IV activities. Analogously to the functions of plastid-localized CRM proteins, analysis of the RNA profiles in wildtype and mcsf1 plants showed that mCSF1 acts in the splicing of many of the group II intron RNAs in Arabidopsis mitochondria. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

Arabidopsis VARIEGATED 3 encodes a chloroplasttargeted, zinc-finger protein required for chloroplast and palisade cell development

DEFF Research Database (Denmark)

Næsted, Henrik; Holm, A.; Jenkins, T.

2004-01-01

The stable, recessive Arabidopsis variegated 3 (var3) mutant exhibits a variegated phenotype due to somatic areas lacking or containing developmentally retarded chloroplasts and greatly reduced numbers of palisade cells. The VAR3 gene, isolated by transposon tagging, encodes the 85.9 kDa VAR3...... that pigment profiles are qualitatively similar in wild type and var3, although var3 accumulates lower levels of chlorophylls and carotenoids. These results indicate that VAR3 is a part of a protein complex required for normal chloroplast and palisade cell development....

Elongator Plays a Positive Role in Exogenous NAD-Induced Defense Responses in Arabidopsis.

Science.gov (United States)

An, Chuanfu; Ding, Yezhang; Zhang, Xudong; Wang, Chenggang; Mou, Zhonglin

2016-05-01

Extracellular NAD is emerging as an important signal molecule in animal cells, but its role in plants has not been well-established. Although it has been shown that exogenous NAD(+) activates defense responses in Arabidopsis, components in the exogenous NAD(+)-activated defense pathway remain to be fully discovered. In a genetic screen for mutants insensitive to exogenous NAD(+) (ien), we isolated a mutant named ien2. Map-based cloning revealed that IEN2 encodes ELONGATA3 (ELO3)/AtELP3, a subunit of the Arabidopsis Elongator complex, which functions in multiple biological processes, including histone modification, DNA (de)methylation, and transfer RNA modification. Mutations in the ELO3/AtELP3 gene compromise exogenous NAD(+)-induced expression of pathogenesis-related (PR) genes and resistance to the bacterial pathogen Pseudomonas syringae pv. maculicola ES4326, and transgenic expression of the coding region of ELO3/AtELP3 in elo3/Atelp3 restores NAD(+) responsiveness to the mutant plants, demonstrating that ELO3/AtELP3 is required for exogenous NAD(+)-induced defense responses. Furthermore, mutations in genes encoding the other five Arabidopsis Elongator subunits (ELO2/AtELP1, AtELP2, ELO1/AtELP4, AtELP5, and AtELP6) also compromise exogenous NAD(+)-induced PR gene expression and resistance to P. syringae pv. maculicola ES4326. These results indicate that the Elongator complex functions as a whole in exogenous NAD(+)-activated defense signaling in Arabidopsis.

Arabidopsis CDS blastp result: AK242601 [KOME

Lifescience Database Archive (English)

Full Text Available AK242601 J090014G03 At4g38190.1 68417.m05391 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-5 (gi:9622882) from Zea mays 0.0 ...

Arabidopsis CDS blastp result: AK242601 [KOME

Lifescience Database Archive (English)

Full Text Available AK242601 J090014G03 At4g23990.1 68417.m03448 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 2e-26 ...

Arabidopsis CDS blastp result: AK242601 [KOME

Lifescience Database Archive (English)

Full Text Available AK242601 J090014G03 At2g32540.1 68415.m03975 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 3e-31 ...

Arabidopsis CDS blastp result: AK242601 [KOME

Lifescience Database Archive (English)

Full Text Available AK242601 J090014G03 At4g23990.1 68417.m03448 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 8e-25 ...

Arabidopsis CDS blastp result: AK242601 [KOME

Lifescience Database Archive (English)

Full Text Available AK242601 J090014G03 At2g32530.1 68415.m03974 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 2e-29 ...

Arabidopsis CDS blastp result: AK242601 [KOME

Lifescience Database Archive (English)

Full Text Available AK242601 J090014G03 At2g32540.1 68415.m03975 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 2e-45 ...

Arabidopsis CDS blastp result: AK242601 [KOME

Lifescience Database Archive (English)

Full Text Available AK242601 J090014G03 At5g16910.1 68418.m01982 cellulose synthase family protein similar to gi:2827143 cellulo...se synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 0.0 ...

Overexpression of an alfalfa GDP-mannose 3, 5-epimerase gene enhances acid, drought and salt tolerance in transgenic Arabidopsis by increasing ascorbate accumulation.

Science.gov (United States)

Ma, Lichao; Wang, Yanrong; Liu, Wenxian; Liu, Zhipeng

2014-11-01

GDP-mannose 3', 5'-epimerase (GME) catalyses the conversion of GDP-D-mannose to GDP-L-galactose, an important step in the ascorbic acid (ascorbic acid) biosynthetic pathway in higher plants. In this study, a novel cDNA fragment (MsGME) encoding a GME protein was isolated and characterised from alfalfa (Medicago sativa). An expression analysis confirmed that MsGME expression was induced by salinity, PEG and acidity stresses. MsGME overexpression in Arabidopsis enhanced tolerance of the transgenic plants to salt, drought and acid. Real-time PCR analysis revealed that the transcript levels of GDP-D-mannose pyrophosphorylase (GMP), L-galactose-phosphate 1-P phosphatase (GP) and GDP-L-galactose phosphorylase (GGP) were increased in transgenic Arabidopsis (T3 generation). Moreover, the ascorbate content was increased in transgenic Arabidopsis. Our results suggest that MsGME can effectively enhance tolerance of transgenic Arabidopsis to acid, drought and salt by increasing ascorbate accumulation.

Arabidopsis CDS blastp result: AK109812 [KOME

Lifescience Database Archive (English)

Full Text Available AK109812 002-147-H02 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 5e-90 ...

Mutations in a plastid-localized elongation factor G alter early stages of plastid development in Arabidopsis thaliana

Directory of Open Access Journals (Sweden)

Hangarter Roger P

2007-07-01

Full Text Available Abstract Background Proper development of plastids in embryo and seedling tissues is critical for plant development. During germination, plastids develop to perform many critical functions that are necessary to establish the seedling for further growth. A growing body of work has demonstrated that components of the plastid transcription and translation machinery must be present and functional to establish the organelle upon germination. Results We have identified Arabidopsis thaliana mutants in a gene that encodes a plastid-targeted elongation factor G (SCO1 that is essential for plastid development during embryogenesis since two T-DNA insertion mutations in the coding sequence (sco1-2 and sco1-3 result in an embryo-lethal phenotype. In addition, a point mutation allele (sco1-1 and an allele with a T-DNA insertion in the promoter (sco1-4 of SCO1 display conditional seedling-lethal phenotypes. Seedlings of these alleles exhibit cotyledon and hypocotyl albinism due to improper chloroplast development, and normally die shortly after germination. However, when germinated on media supplemented with sucrose, the mutant plants can produce photosynthetically-active green leaves from the apical meristem. Conclusion The developmental stage-specific phenotype of the conditional-lethal sco1 alleles reveals differences in chloroplast formation during seedling germination compared to chloroplast differentiation in cells derived from the shoot apical meristem. Our identification of embryo-lethal mutant alleles in the Arabidopsis elongation factor G indicates that SCO1 is essential for plant growth, consistent with its predicted role in chloroplast protein translation.

The Arabidopsis homolog of human G3BP1 is a key regulator of stomatal and apoplastic immunity

KAUST Repository

Abulfaraj, Aala A.; Mariappan, Kiruthiga; Bigeard, Jean; Manickam, Prabhu; Blilou, Ikram; Guo, Xiujie; Al-Babili, Salim; Pflieger, Delphine; Hirt, Heribert; Rayapuram, Naganand

2018-01-01

Mammalian Ras-GTPase–activating protein SH3-domain–binding proteins (G3BPs) are a highly conserved family of RNA-binding proteins that link kinase receptor-mediated signaling to RNA metabolism. Mammalian G3BP1 is a multifunctional protein that functions in viral immunity. Here, we show that the Arabidopsis thaliana homolog of human G3BP1 negatively regulates plant immunity. Arabidopsis g3bp1 mutants showed enhanced resistance to the virulent bacterial pathogen Pseudomonas syringae pv. tomato. Pathogen resistance was mediated in Atg3bp1 mutants by altered stomatal and apoplastic immunity. Atg3bp1 mutants restricted pathogen entry into stomates showing insensitivity to bacterial coronatine–mediated stomatal reopening. AtG3BP1 was identified as a negative regulator of defense responses, which correlated with moderate up-regulation of salicylic acid biosynthesis and signaling without growth penalty.

The Arabidopsis homolog of human G3BP1 is a key regulator of stomatal and apoplastic immunity

KAUST Repository

Abulfaraj, Aala Abdulaziz Hussien

2018-05-31

Mammalian Ras-GTPase–activating protein SH3-domain–binding proteins (G3BPs) are a highly conserved family of RNA-binding proteins that link kinase receptor-mediated signaling to RNA metabolism. Mammalian G3BP1 is a multifunctional protein that functions in viral immunity. Here, we show that the Arabidopsis thaliana homolog of human G3BP1 negatively regulates plant immunity. Arabidopsis g3bp1 mutants showed enhanced resistance to the virulent bacterial pathogen Pseudomonas syringae pv. tomato. Pathogen resistance was mediated in Atg3bp1 mutants by altered stomatal and apoplastic immunity. Atg3bp1 mutants restricted pathogen entry into stomates showing insensitivity to bacterial coronatine–mediated stomatal reopening. AtG3BP1 was identified as a negative regulator of defense responses, which correlated with moderate up-regulation of salicylic acid biosynthesis and signaling without growth penalty.

An Arabidopsis callose synthase

DEFF Research Database (Denmark)

Ostergaard, Lars; Petersen, Morten; Mattsson, Ole

2002-01-01

in the Arabidopsis mpk4 mutant which exhibits systemic acquired resistance (SAR), elevated beta-1,3-glucan synthase activity, and increased callose levels. In addition, AtGsl5 is a likely target of salicylic acid (SA)-dependent SAR, since AtGsl5 mRNA accumulation is induced by SA in wild-type plants, while...... expression of the nahG salicylate hydroxylase reduces AtGsl5 mRNA levels in the mpk4 mutant. These results indicate that AtGsl5 is likely involved in callose synthesis in flowering tissues and in the mpk4 mutant....

Arabidopsis CDS blastp result: AK241312 [KOME

Lifescience Database Archive (English)

Full Text Available AK241312 J065141L09 At4g32040.1 68417.m04561 homeobox protein knotted-1 like 5 (KNAT5) / home...odomain containing protein 1 (H1) identical to homeobox protein knotted-1 like 5 (KNAT5) SP:P48002 from [Arabidopsis thaliana] 2e-19 ...

Arabidopsis CDS blastp result: AK243352 [KOME

Lifescience Database Archive (English)

Full Text Available AK243352 J100060L07 At4g32040.1 68417.m04561 homeobox protein knotted-1 like 5 (KNAT5) / home...odomain containing protein 1 (H1) identical to homeobox protein knotted-1 like 5 (KNAT5) SP:P48002 from [Arabidopsis thaliana] 1e-103 ...

Arabidopsis CDS blastp result: AK289177 [KOME

Lifescience Database Archive (English)

Full Text Available AK289177 J100024E07 At4g32040.1 68417.m04561 homeobox protein knotted-1 like 5 (KNAT5) / home...odomain containing protein 1 (H1) identical to homeobox protein knotted-1 like 5 (KNAT5) SP:P48002 from [Arabidopsis thaliana] 4e-98 ...

Cloning of human genes encoding novel G protein-coupled receptors

Energy Technology Data Exchange (ETDEWEB)

Marchese, A.; Docherty, J.M.; Heiber, M. [Univ. of Toronto, (Canada)] [and others

1994-10-01

We report the isolation and characterization of several novel human genes encoding G protein-coupled receptors. Each of the receptors contained the familiar seven transmembrane topography and most closely resembled peptide binding receptors. Gene GPR1 encoded a receptor protein that is intronless in the coding region and that shared identity (43% in the transmembrane regions) with the opioid receptors. Northern blot analysis revealed that GPR1 transcripts were expressed in the human hippocampus, and the gene was localized to chromosome 15q21.6. Gene GPR2 encoded a protein that most closely resembled an interleukin-8 receptor (51% in the transmembrane regions), and this gene, not expressed in the six brain regions examined, was localized to chromosome 17q2.1-q21.3. A third gene, GPR3, showed identity (56% in the transmembrane regions) with a previously characterized cDNA clone from rat and was localized to chromosome 1p35-p36.1. 31 refs., 5 figs., 1 tab.

Arabidopsis CDS blastp result: AK109848 [KOME

Lifescience Database Archive (English)

Full Text Available AK109848 002-148-F05 At4g37750.1 ovule development protein aintegumenta (ANT) ident...ical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 5e-73 ...

Co-overexpressing a plasma membrane and a vacuolar membrane sodium/proton antiporter significantly improves salt tolerance in transgenic Arabidopsis plants.

Science.gov (United States)

The Arabidopsis gene AtNHX1 encodes a vacuolar membrane bound sodium/proton (Sodium/Hydrogen) antiporter that transports sodium into the vacuole and exports hydrogen into the cytoplasm. The Arabidopsis gene SOS1 encodes a plasma membrane bound sodium/hydrogen antiporter that exports sodium to the ex...

Arabidopsis CDS blastp result: AK240892 [KOME

Lifescience Database Archive (English)

Full Text Available AK240892 J065030K10 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 5e-88 ...

Arabidopsis CDS blastp result: AK287621 [KOME

Lifescience Database Archive (English)

Full Text Available AK287621 J065066I09 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 5e-85 ...

Investigating the Role of the Arabidopsis Homologue of the Human G3BP in RNA Metabolism, Cellular Stress Responses and Innate Immunity

KAUST Repository

Abulfaraj, Aala A.

2018-04-01

Mitogen-activated protein kinases (MAPKs) belong to the most conserved signaling pathways and are found in all eukaryotes, including humans where they play important roles in various diseases and cancer. Stimulation of this signal transduction pathway by microbe-associated molecular patterns (MAMP) results in a multitude of events to regulate innate immune responses in Arabidopsis thaliana stimulating large-scale changes in gene expression. Starting from a phosphoproteomic screen in Arabidopsis thaliana wild type and mpk3, mpk4 and mpk6 mutants following microbe-associated molecular pattern (MAMP) treatment, several novel chromatin-associated proteins were identified that are differentially phosphorylated by stress-induced protein kinases. Arabidopsis Ras GTPase-activating protein SH3-domain-binding protein (AtG3BP-1) is a downstream putative substrate of the MAMP-stimulated MAPK pathway that is phosphorylated by MPK3, 4 and 6 in in vitro kinase assays. AtG3BP1 belongs to a highly conserved family of RNA-binding proteins in eukaryotes that link kinase receptormediated signaling to RNA metabolism. Here, we report the characterization of the Arabidopsis homolog of human G3BP1 in plant innate immunity. AtG3BP1 negatively regulates plant immunity and defense immune responses. Atg3bp1 mutant lines show constitutive stomata closure, expression of a number of key defense marker genes, and accumulate salicylic acid but not jasmonic acid. Furthermore, Atg3bp1 plants exhibit enhanced resistance to the biotrophic pathogen Pseudomonas syringae pv. tomato. Pathogen resistance was mediated by stomatal and apoplastic immunity in Atg3bp1. More generally, our data reinforce that AtG3BP1 is a key mediator of plant defense responses and transient expression of AtG3BP1 delivered striking disease resistance in the absence of yield penalty, highlighting a potential application of this gene in crop protection.

Arabidopsis CDS blastp result: AK105718 [KOME

Lifescience Database Archive (English)

Full Text Available AK105718 001-201-F09 At5g43560.2 meprin and TRAF homology domain-containing protein / MATH... domain-containing protein weak similarity to ubiquitin-specific protease 12 [Arabidopsis thaliana] GI:11993471; contains Pfam profile PF00917: MATH domain 5e-22 ...

Recombination Rate Heterogeneity within Arabidopsis Disease Resistance Genes.

Science.gov (United States)

Choi, Kyuha; Reinhard, Carsten; Serra, Heïdi; Ziolkowski, Piotr A; Underwood, Charles J; Zhao, Xiaohui; Hardcastle, Thomas J; Yelina, Nataliya E; Griffin, Catherine; Jackson, Matthew; Mézard, Christine; McVean, Gil; Copenhaver, Gregory P; Henderson, Ian R

2016-07-01

Meiotic crossover frequency varies extensively along chromosomes and is typically concentrated in hotspots. As recombination increases genetic diversity, hotspots are predicted to occur at immunity genes, where variation may be beneficial. A major component of plant immunity is recognition of pathogen Avirulence (Avr) effectors by resistance (R) genes that encode NBS-LRR domain proteins. Therefore, we sought to test whether NBS-LRR genes would overlap with meiotic crossover hotspots using experimental genetics in Arabidopsis thaliana. NBS-LRR genes tend to physically cluster in plant genomes; for example, in Arabidopsis most are located in large clusters on the south arms of chromosomes 1 and 5. We experimentally mapped 1,439 crossovers within these clusters and observed NBS-LRR gene associated hotspots, which were also detected as historical hotspots via analysis of linkage disequilibrium. However, we also observed NBS-LRR gene coldspots, which in some cases correlate with structural heterozygosity. To study recombination at the fine-scale we used high-throughput sequencing to analyze ~1,000 crossovers within the RESISTANCE TO ALBUGO CANDIDA1 (RAC1) R gene hotspot. This revealed elevated intragenic crossovers, overlapping nucleosome-occupied exons that encode the TIR, NBS and LRR domains. The highest RAC1 recombination frequency was promoter-proximal and overlapped CTT-repeat DNA sequence motifs, which have previously been associated with plant crossover hotspots. Additionally, we show a significant influence of natural genetic variation on NBS-LRR cluster recombination rates, using crosses between Arabidopsis ecotypes. In conclusion, we show that a subset of NBS-LRR genes are strong hotspots, whereas others are coldspots. This reveals a complex recombination landscape in Arabidopsis NBS-LRR genes, which we propose results from varying coevolutionary pressures exerted by host-pathogen relationships, and is influenced by structural heterozygosity.

DOG1-like genes in cereals: investigation of their function by means of ectopic expression in Arabidopsis.

Science.gov (United States)

Ashikawa, Ikuo; Abe, Fumitaka; Nakamura, Shingo

2013-07-01

The Arabidopsis gene DOG1 (AtDOG1) functions in seed dormancy and in sugar signaling. Little is known about the structural and functional features of plant genes homologous to AtDOG1, except for one type (clade 1) of Triticeae AtDOG1-like genes, which was previously demonstrated to be functionally orthologous to AtDOG1. Here, through phylogenetic, structural, and functional analyses of cereal AtDOG1-like genes, we characterized their features: these genes exist as a gene family that can be classified into five distinct clades (1-5). Of these, AtDOG1-like genes in clades 1-4 have a similar architecture to AtDOG1: they encode proteins with three conserved regions. In contrast, the clade 5 genes are distinct; their encoded proteins lack these conserved regions, but harbor domains that interact with DNA. Ectopic expression of the cereal AtDOG1-like genes of clades 2-4 in Arabidopsis demonstrated that like the clade 1 genes, they performed the same function as AtDOG1. The correlation between the depth of seed dormancy and the efficiency of sugar signaling in transgenic Arabidopsis conferred by genes in clades 1-4 suggests a close link in the underlying mechanisms between the seed dormancy and sugar signaling functions of AtDOG1. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The Arabidopsis SKU5 gene encodes an extracellular glycosyl phosphatidylinositol-anchored glycoprotein involved in directional root growth

Science.gov (United States)

Sedbrook, John C.; Carroll, Kathleen L.; Hung, Kai F.; Masson, Patrick H.; Somerville, Chris R.

2002-01-01

To investigate how roots respond to directional cues, we characterized a T-DNA-tagged Arabidopsis mutant named sku5 in which the roots skewed and looped away from the normal downward direction of growth on inclined agar surfaces. sku5 roots and etiolated hypocotyls were slightly shorter than normal and exhibited a counterclockwise (left-handed) axial rotation bias. The surface-dependent skewing phenotype disappeared when the roots penetrated the agar surface, but the axial rotation defect persisted, revealing that these two directional growth processes are separable. The SKU5 gene belongs to a 19-member gene family designated SKS (SKU5 Similar) that is related structurally to the multiple-copper oxidases ascorbate oxidase and laccase. However, the SKS proteins lack several of the conserved copper binding motifs characteristic of copper oxidases, and no enzymatic function could be assigned to the SKU5 protein. Analysis of plants expressing SKU5 reporter constructs and protein gel blot analysis showed that SKU5 was expressed most strongly in expanding tissues. SKU5 was glycosylated and modified by glycosyl phosphatidylinositol and localized to both the plasma membrane and the cell wall. Our observations suggest that SKU5 affects two directional growth processes, possibly by participating in cell wall expansion.

Remobilization of Phytol from Chlorophyll Degradation Is Essential for Tocopherol Synthesis and Growth of Arabidopsis

Science.gov (United States)

vom Dorp, Katharina; Hölzl, Georg; Plohmann, Christian; Eisenhut, Marion; Abraham, Marion

2015-01-01

Phytol from chlorophyll degradation can be phosphorylated to phytyl-phosphate and phytyl-diphosphate, the substrate for tocopherol (vitamin E) synthesis. A candidate for the phytyl-phosphate kinase from Arabidopsis thaliana (At1g78620) was identified via a phylogeny-based approach. This gene was designated VITAMIN E DEFICIENT6 (VTE6) because the leaves of the Arabidopsis vte6 mutants are tocopherol deficient. The vte6 mutant plants are incapable of photoautotrophic growth. Phytol and phytyl-phosphate accumulate, and the phytyl-diphosphate content is strongly decreased in vte6 leaves. Phytol feeding and enzyme assays with Arabidopsis and recombinant Escherichia coli cells demonstrated that VTE6 has phytyl-P kinase activity. Overexpression of VTE6 resulted in increased phytyl-diphosphate and tocopherol contents in seeds, indicating that VTE6 encodes phytyl-phosphate kinase. The severe growth retardation of vte6 mutants was partially rescued by introducing the phytol kinase mutation vte5. Double mutant plants (vte5 vte6) are tocopherol deficient and contain more chlorophyll, but reduced amounts of phytol and phytyl-phosphate compared with vte6 mutants, suggesting that phytol or phytyl-phosphate are detrimental to plant growth. Therefore, VTE6 represents the missing phytyl-phosphate kinase, linking phytol release from chlorophyll with tocopherol synthesis. Moreover, tocopherol synthesis in leaves depends on phytol derived from chlorophyll, not on de novo synthesis of phytyl-diphosphate from geranylgeranyl-diphosphate. PMID:26452599

Arabidopsis CDS blastp result: AK105393 [KOME

Lifescience Database Archive (English)

Full Text Available AK105393 001-123-B04 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 0.0 ...

Arabidopsis CDS blastp result: AK102695 [KOME

Lifescience Database Archive (English)

Full Text Available AK102695 J033103F21 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 0.0 ...

Arabidopsis CDS blastp result: AK100523 [KOME

Lifescience Database Archive (English)

Full Text Available AK100523 J023100P04 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 0.0 ...

Arabidopsis CDS blastp result: AK065259 [KOME

Lifescience Database Archive (English)

Full Text Available AK065259 J013002J18 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 0.0 ...

Arabidopsis CDS blastp result: AK102134 [KOME

Lifescience Database Archive (English)

Full Text Available AK102134 J033085F12 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 0.0 ...

Arabidopsis CDS blastp result: AK073859 [KOME

Lifescience Database Archive (English)

Full Text Available AK073859 J033073L16 At4g22260.1 alternative oxidase, putative / immutans protein (I...M) identical to IMMUTANS from Arabidopsis thaliana [gi:4138855]; contains Pfam profile PF01786 alternative oxidase 5e-21 ...

Arabidopsis CDS blastp result: AK110534 [KOME

Lifescience Database Archive (English)

Full Text Available AK110534 002-168-A07 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 1e-114 ...

Arabidopsis CDS blastp result: AK066835 [KOME

Lifescience Database Archive (English)

Full Text Available AK066835 J013087I16 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 1e-171 ...

Arabidopsis CDS blastp result: AK103940 [KOME

Lifescience Database Archive (English)

Full Text Available AK103940 001-013-G08 At5g54190.1 protochlorophyllide reductase A, chloroplast / PCR A / NADPH-protochlorophy...llide oxidoreductase A (PORA) identical to SP:Q42536 protochlorophyllide reductase ...A, chloroplast precursor (EC 1.3.1.33) (PCR A) (NADPH-protochlorophyllide oxidoreductase A) (POR A) [Arabidopsis thaliana] 1e-130 ...

Arabidopsis CDS blastp result: AK121003 [KOME

Lifescience Database Archive (English)

Full Text Available AK121003 J023045B21 At2g32540.1 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 1e-167 ...

Arabidopsis CDS blastp result: AK069071 [KOME

Lifescience Database Archive (English)

Full Text Available AK069071 J023010H01 At2g32540.1 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 1e-167 ...

Arabidopsis CDS blastp result: AK061162 [KOME

Lifescience Database Archive (English)

Full Text Available AK061162 006-209-A01 At2g32540.1 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 3e-35 ...

Arabidopsis CDS blastp result: AK060286 [KOME

Lifescience Database Archive (English)

Full Text Available AK060286 001-006-C08 At2g32540.1 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 6e-78 ...

A G-protein β subunit, AGB1, negatively regulates the ABA response and drought tolerance by down-regulating AtMPK6-related pathway in Arabidopsis.

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Dong-bei Xu

Full Text Available Heterotrimeric G-proteins are versatile regulators involved in diverse cellular processes in eukaryotes. In plants, the function of G-proteins is primarily associated with ABA signaling. However, the downstream effectors and the molecular mechanisms in the ABA pathway remain largely unknown. In this study, an AGB1 mutant (agb1-2 was found to show enhanced drought tolerance, indicating that AGB1 might negatively regulate drought tolerance in Arabidopsis. Data showed that AGB1 interacted with protein kinase AtMPK6 that was previously shown to phosphorylate AtVIP1, a transcription factor responding to ABA signaling. Our study found that transcript levels of three ABA responsive genes, AtMPK6, AtVIP1 and AtMYB44 (downstream gene of AtVIP1, were significantly up-regulated in agb1-2 lines after ABA or drought treatments. Other ABA-responsive and drought-inducible genes, such as RD29A (downstream gene of AtMYB44, were also up-regulated in agb1-2 lines. Furthermore, overexpression of AtVIP1 resulted in hypersensitivity to ABA at seed germination and seedling stages, and significantly enhanced drought tolerance in transgenic plants. These results suggest that AGB1 was involved in the ABA signaling pathway and drought tolerance in Arabidopsis through down-regulating the AtMPK6, AtVIP1 and AtMYB44 cascade.

Experimental infection of calves with a gI, gE, US9 negative bovine herpesvirus type 5

NARCIS (Netherlands)

Hubner, S.O.; Oliveira, A.P.; Franco, A.C.; Rijsewijk, F.A.M.; Roehe, P.M.

2005-01-01

In this work, a role for the genes encoding glycoproteins I (gI) and E (gE) and the US9 protein of bovine herpesvirus type 5 (BHV-5) in neuropathogenicity and reactivation of latent infections was examined. Calves infected intranasally with a gI/gE/US9 deleted recombinant shed up to 102.85 TCID50/ml

Arabidopsis thaliana glucuronosyltransferase in family GT14

DEFF Research Database (Denmark)

Dilokpimol, Adiphol; Geshi, Naomi

2014-01-01

Arabinogalactan proteins are abundant cell-surface proteoglycans in plants and are involved in many cellular processes including somatic embryogenesis, cell-cell interactions, and cell elongation. We reported a glucuronosyltransferase encoded by Arabidopsis AtGlcAT14A, which catalyzes an addition...

Natural variants of AtHKT1 enhance Na+ accumulation in two wild populations of Arabidopsis.

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Ana Rus

2006-12-01

Full Text Available Plants are sessile and therefore have developed mechanisms to adapt to their environment, including the soil mineral nutrient composition. Ionomics is a developing functional genomic strategy designed to rapidly identify the genes and gene networks involved in regulating how plants acquire and accumulate these mineral nutrients from the soil. Here, we report on the coupling of high-throughput elemental profiling of shoot tissue from various Arabidopsis accessions with DNA microarray-based bulk segregant analysis and reverse genetics, for the rapid identification of genes from wild populations of Arabidopsis that are involved in regulating how plants acquire and accumulate Na(+ from the soil. Elemental profiling of shoot tissue from 12 different Arabidopsis accessions revealed that two coastal populations of Arabidopsis collected from Tossa del Mar, Spain, and Tsu, Japan (Ts-1 and Tsu-1, respectively, accumulate higher shoot levels of Na(+ than do Col-0 and other accessions. We identify AtHKT1, known to encode a Na(+ transporter, as being the causal locus driving elevated shoot Na(+ in both Ts-1 and Tsu-1. Furthermore, we establish that a deletion in a tandem repeat sequence approximately 5 kb upstream of AtHKT1 is responsible for the reduced root expression of AtHKT1 observed in these accessions. Reciprocal grafting experiments establish that this loss of AtHKT1 expression in roots is responsible for elevated shoot Na(+. Interestingly, and in contrast to the hkt1-1 null mutant, under NaCl stress conditions, this novel AtHKT1 allele not only does not confer NaCl sensitivity but also cosegregates with elevated NaCl tolerance. We also present all our elemental profiling data in a new open access ionomics database, the Purdue Ionomics Information Management System (PiiMS; http://www.purdue.edu/dp/ionomics. Using DNA microarray-based genotyping has allowed us to rapidly identify AtHKT1 as the casual locus driving the natural variation in shoot Na

Expression pattern of a nuclear encoded mitochondrial arginine-ornithine translocator gene from Arabidopsis

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Schneider Anja

2003-01-01

Full Text Available Abstract Background Arginine and citrulline serve as nitrogen storage forms, but are also involved in biosynthetic and catabolic pathways. Metabolism of arginine, citrulline and ornithine is distributed between mitochondria and cytosol. For the shuttle of intermediates between cytosol and mitochondria transporters present on the inner mitochondrial membrane are required. Yeast contains a mitochondrial translocator for ornithine and arginine, Ort1p/Arg11p. Ort1p/Arg11p is a member of the mitochondrial carrier family (MCF essential for ornithine export from mitochondria. The yeast arg11 mutant, which is deficient in Ort1p/Arg11p grows poorly on media lacking arginine. Results High-level expression of a nuclear encoded Arabidopsis thaliana homolog (AtmBAC2 of Ort1p/Arg11p was able to suppress the growth deficiency of arg11. RT-PCR analysis demonstrated expression of AtmBAC2 in all tissues with highest levels in flowers. Promoter-GUS fusions showed preferential expression in flowers, i.e. pollen, in the vasculature of siliques and in aborted seeds. Variable expression was observed in leaf vasculature. Induction of the promoter was not observed during the first two weeks in seedlings grown on media containing NH4NO3, arginine or ornithine as sole nitrogen sources. Conclusion AtmBAC2 was isolated as a mitochondrial transporter for arginine in Arabidopsis. The absence of expression in developing seeds and in cotyledons of seedlings indicates that other transporters are responsible for storage and mobilization of arginine in seeds.

Arabidopsis CDS blastp result: AK241679 [KOME

Lifescience Database Archive (English)

Full Text Available AK241679 J065193F24 At3g29410.1 68416.m03695 terpene synthase/cyclase family protein similar to terpene... synthase GB:CAA72074 from [Arabidopsis thaliana], contains Pfam profile: PF01397 terpene synthase family 5e-65 ...

Arabidopsis CDS blastp result: AK071661 [KOME

Lifescience Database Archive (English)

Full Text Available AK071661 J023105D07 At5g37770.1 touch-responsive protein / calmodulin-related protein 2, touch...-induced (TCH2) identical to calmodulin-related protein 2,touch-induced SP:P25070 from [Arabidopsis thaliana] 3e-33 ...

Arabidopsis CDS blastp result: AK108506 [KOME

Lifescience Database Archive (English)

Full Text Available AK108506 002-143-H11 At5g37770.1 touch-responsive protein / calmodulin-related protein 2, touch...-induced (TCH2) identical to calmodulin-related protein 2,touch-induced SP:P25070 from [Arabidopsis thaliana] 7e-14 ...

Arabidopsis CDS blastp result: AK062711 [KOME

Lifescience Database Archive (English)

Full Text Available AK062711 001-106-C02 At5g37770.1 touch-responsive protein / calmodulin-related protein 2, touch...-induced (TCH2) identical to calmodulin-related protein 2,touch-induced SP:P25070 from [Arabidopsis thaliana] 9e-34 ...

Arabidopsis CDS blastp result: AK242472 [KOME

Lifescience Database Archive (English)

Full Text Available AK242472 J080303B22 At5g46200.1 68418.m05684 expressed protein contains similarity to carboxyl-term...inal proteinase contains Pfam profile PF03080: Arabidopsis proteins of unknown function; expression supported by MPSS 2e-33 ...

Arabidopsis CDS blastp result: AK288612 [KOME

Lifescience Database Archive (English)

Full Text Available AK288612 J090053J15 At4g16390.1 68417.m02481 chloroplastic RNA-binding protein P67,... putative nearly identical to 67kD chloroplastic RNA-binding protein, P67 [Arabidopsis thaliana] GI:9755842 5e-24 ...

Arabidopsis CDS blastp result: AK242585 [KOME

Lifescience Database Archive (English)

Full Text Available AK242585 J090010M20 At4g38190.1 68417.m05391 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-5 (gi:9622882) from Zea mays 8e-63 ...

Arabidopsis CDS blastp result: AK242890 [KOME

Lifescience Database Archive (English)

Full Text Available AK242890 J090079L19 At2g32540.1 68415.m03975 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 4e-47 ...

Arabidopsis CDS blastp result: AK242585 [KOME

Lifescience Database Archive (English)

Full Text Available AK242585 J090010M20 At5g16910.1 68418.m01982 cellulose synthase family protein similar to gi:2827143 cellulo...se synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 1e-28 ...

Arabidopsis CDS blastp result: AK242890 [KOME

Lifescience Database Archive (English)

Full Text Available AK242890 J090079L19 At4g23990.1 68417.m03448 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 1e-45 ...

Arabidopsis CDS blastp result: AK242585 [KOME

Lifescience Database Archive (English)

Full Text Available AK242585 J090010M20 At5g16910.1 68418.m01982 cellulose synthase family protein similar to gi:2827143 cellulo...se synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 2e-65 ...

Arabidopsis CDS blastp result: AK242585 [KOME

Lifescience Database Archive (English)

Full Text Available AK242585 J090010M20 At4g23990.1 68417.m03448 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 1e-124 ...

Arabidopsis CDS blastp result: AK242890 [KOME

Lifescience Database Archive (English)

Full Text Available AK242890 J090079L19 At5g16910.1 68418.m01982 cellulose synthase family protein similar to gi:2827143 cellulo...se synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 1e-130 ...

Arabidopsis CDS blastp result: AK242890 [KOME

Lifescience Database Archive (English)

Full Text Available AK242890 J090079L19 At4g38190.1 68417.m05391 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-5 (gi:9622882) from Zea mays 1e-125 ...

Arabidopsis CDS blastp result: AK242585 [KOME

Lifescience Database Archive (English)

Full Text Available AK242585 J090010M20 At2g32540.1 68415.m03975 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 4e-98 ...

Arabidopsis CDS blastp result: AK242585 [KOME

Lifescience Database Archive (English)

Full Text Available AK242585 J090010M20 At2g32530.1 68415.m03974 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 8e-98 ...

Arabidopsis CDS blastp result: AK242585 [KOME

Lifescience Database Archive (English)

Full Text Available AK242585 J090010M20 At4g38190.1 68417.m05391 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-5 (gi:9622882) from Zea mays 4e-27 ...

Arabidopsis CDS blastp result: AK242890 [KOME

Lifescience Database Archive (English)

Full Text Available AK242890 J090079L19 At2g32530.1 68415.m03974 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 4e-50 ...

Dissecting a hidden gene duplication: the Arabidopsis thaliana SEC10 locus.

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Nemanja Vukašinović

Full Text Available Repetitive sequences present a challenge for genome sequence assembly, and highly similar segmental duplications may disappear from assembled genome sequences. Having found a surprising lack of observable phenotypic deviations and non-Mendelian segregation in Arabidopsis thaliana mutants in SEC10, a gene encoding a core subunit of the exocyst tethering complex, we examined whether this could be explained by a hidden gene duplication. Re-sequencing and manual assembly of the Arabidopsis thaliana SEC10 (At5g12370 locus revealed that this locus, comprising a single gene in the reference genome assembly, indeed contains two paralogous genes in tandem, SEC10a and SEC10b, and that a sequence segment of 7 kb in length is missing from the reference genome sequence. Differences between the two paralogs are concentrated in non-coding regions, while the predicted protein sequences exhibit 99% identity, differing only by substitution of five amino acid residues and an indel of four residues. Both SEC10 genes are expressed, although varying transcript levels suggest differential regulation. Homozygous T-DNA insertion mutants in either paralog exhibit a wild-type phenotype, consistent with proposed extensive functional redundancy of the two genes. By these observations we demonstrate that recently duplicated genes may remain hidden even in well-characterized genomes, such as that of A. thaliana. Moreover, we show that the use of the existing A. thaliana reference genome sequence as a guide for sequence assembly of new Arabidopsis accessions or related species has at least in some cases led to error propagation.

Disruption of ATCSLD5 results in reduced growth, reduced xylan and homogalacturonan synthase activity and altered xylan occurrence in Arabidopsis

DEFF Research Database (Denmark)

Bernal Giraldo, Adriana Jimena; Jensen, Jacob Krüger; Harholt, Jesper

2007-01-01

Members of a large family of cellulose synthase-like genes (CSLs) are predicted to encode glycosyl transferases (GTs) involved in the biosynthesis of plant cell walls. The CSLA and CSLF families are known to contain mannan and glucan synthases, respectively, but the products of other CSLs...... are unknown. Here we report the effects of disrupting ATCSLD5 expression in Arabidopsis. Both stem and root growth were significantly reduced in ATCSLD5 knock-out plants, and these plants also had increased susceptibility to the cellulose synthase inhibitor isoxaben. Antibody and carbohydrate-binding module...

Structural insights of the ssDNA binding site in the multifunctional endonuclease AtBFN2 from Arabidopsis thaliana.

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Tsung-Fu Yu

Full Text Available The multi S1/P1 nuclease AtBFN2 (EC 3.1.30.1 encoded by the Arabidopsis thaliana At1g68290 gene is a glycoprotein that digests RNA, ssDNA, and dsDNA. AtBFN2 depends on three zinc ions for cleaving DNA and RNA at 3'-OH to yield 5'-nucleotides. In addition, AtBFN2's enzymatic activity is strongly glycan dependent. Plant Zn(2+-dependent endonucleases present a unique fold, and belong to the Phospholipase C (PLC/P1 nuclease superfamily. In this work, we present the first complete, ligand-free, AtBFN2 crystal structure, along with sulfate, phosphate and ssDNA co-crystal structures. With these, we were able to provide better insight into the glycan structure and possible enzymatic mechanism. In comparison with other nucleases, the AtBFN2/ligand-free and AtBFN2/PO4 models suggest a similar, previously proposed, catalytic mechanism. Our data also confirm that the phosphate and vanadate can inhibit the enzyme activity by occupying the active site. More importantly, the AtBFN2/A5T structure reveals a novel and conserved secondary binding site, which seems to be important for plant Zn(2+-dependent endonucleases. Based on these findings, we propose a rational ssDNA binding model, in which the ssDNA wraps itself around the protein and the attached surface glycan, in turn, reinforces the binding complex.

Arabidopsis CDS blastp result: AK242428 [KOME

Lifescience Database Archive (English)

Full Text Available AK242428 J080089P09 At5g37770.1 68418.m04547 touch-responsive protein / calmodulin-related protein 2, touch...-induced (TCH2) identical to calmodulin-related protein 2,touch-induced SP:P25070 from [Arabidopsis thaliana] 9e-19 ...

Arabidopsis CDS blastp result: AK241786 [KOME

Lifescience Database Archive (English)

Full Text Available AK241786 J065207F05 At5g37770.1 68418.m04547 touch-responsive protein / calmodulin-related protein 2, touch...-induced (TCH2) identical to calmodulin-related protein 2,touch-induced SP:P25070 from [Arabidopsis thaliana] 1e-19 ...

Arabidopsis CDS blastp result: AK242346 [KOME

Lifescience Database Archive (English)

Full Text Available AK242346 J080012M07 At5g37770.1 68418.m04547 touch-responsive protein / calmodulin-related protein 2, touch...-induced (TCH2) identical to calmodulin-related protein 2,touch-induced SP:P25070 from [Arabidopsis thaliana] 2e-11 ...

Arabidopsis CDS blastp result: AK242346 [KOME

Lifescience Database Archive (English)

Full Text Available AK242346 J080012M07 At5g37770.1 68418.m04547 touch-responsive protein / calmodulin-related protein 2, touch...-induced (TCH2) identical to calmodulin-related protein 2,touch-induced SP:P25070 from [Arabidopsis thaliana] 2e-25 ...

Arabidopsis CDS blastp result: AK243656 [KOME

Lifescience Database Archive (English)

Full Text Available AK243656 J100088L22 At2g41100.2 68415.m05077 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 5e-20 ...

Arabidopsis CDS blastp result: AK061037 [KOME

Lifescience Database Archive (English)

Full Text Available AK061037 006-205-B07 At5g65670.2 auxin-responsive protein / indoleacetic acid-induc...ed protein 9 (IAA9) identical to SP|Q38827 Auxin-responsive protein IAA9 (Indoleacetic acid-induced protein 9) {Arabidopsis thaliana} 2e-25 ...

Mining the active proteome of Arabidopsis thaliana

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Renier A. L. Van Der Hoorn

2011-11-01

Full Text Available Assigning functions to the >30.000 proteins encoded by the Arabidopsis genome is a challenging task of the Arabidopsis Functional Genomics Network. Although genome-wide technologies like proteomics and transcriptomics have generated a wealth of information that significantly accelerated gene annotation, protein activities are poorly predicted by transcript or protein levels as protein activities are post-translationally regulated. To directly display protein activities in Arabidopsis proteomes, we developed and applied Activity-based Protein Profiling (ABPP. ABPP is based on the use of small molecule probes that react with the catalytic residues of distinct protein classes in an activity-dependent manner. Labeled proteins are separated and detected from proteins gels and purified and identified by mass spectrometry. Using probes of six different chemotypes we have displayed of activities of 76 Arabidopsis proteins. These proteins represent over ten different protein classes that contain over 250 Arabidopsis proteins, including cysteine- serine- and metallo-proteases, lipases, acyltransferases, and the proteasome. We have developed methods for identification of in vivo labeled proteins using click-chemistry and for in vivo imaging with fluorescent probes. In vivo labeling has revealed novel protein activities and unexpected subcellular activities of the proteasome. Labeling of extracts displayed several differential activities e.g. of the proteasome during immune response and methylesterases during infection. These studies illustrate the power of ABPP to display the functional proteome and testify to a successful interdisciplinary collaboration involving chemical biology, organic chemistry and proteomics.

AtPP2CG1, a protein phosphatase 2C, positively regulates salt tolerance of Arabidopsis in abscisic acid-dependent manner

International Nuclear Information System (INIS)

Liu, Xin; Zhu, Yanming; Zhai, Hong; Cai, Hua; Ji, Wei; Luo, Xiao; Li, Jing; Bai, Xi

2012-01-01

Highlights: ► AtPP2CG1 positively regulates salt tolerance in ABA-dependent manner. ► AtPP2CG1 up-regulates the expression of marker genes in different pathways. ► AtPP2CG1 expresses in the vascular system and trichomes of Arabidopsis. -- Abstract: AtPP2CG1 (Arabidopsis thaliana protein phosphatase 2C G Group 1) was predicted as an abiotic stress candidate gene by bioinformatic analysis in our previous study. The gene encodes a putative protein phosphatase 2C that belongs to Group G of PP2C. There is no report of Group G genes involved in abiotic stress so far. Real-time RT-PCR analysis showed that AtPP2CG1 expression was induced by salt, drought, and abscisic acid (ABA) treatment. The expression levels of AtPP2CG1 in the ABA synthesis-deficient mutant abi2–3 were much lower than that in WT plants under salt stress suggesting that the expression of AtPP2CG1 acts in an ABA-dependent manner. Over-expression of AtPP2CG1 led to enhanced salt tolerance, whereas its loss of function caused decreased salt tolerance. These results indicate that AtPP2CG1 positively regulates salt stress in an ABA-dependent manner. Under salt treatment, AtPP2CG1 up-regulated the expression levels of stress-responsive genes, including RD29A, RD29B, DREB2A and KIN1. GUS activity was detected in roots, leaves, stems, flower, and trichomes of AtPP2CG1 promoter–GUS transgenic plants. AtPP2CG1 protein was localized in nucleus and cytoplasm via AtPP2CG1:eGFP and YFP:AtPP2CG1 fusion approaches.

AtPP2CG1, a protein phosphatase 2C, positively regulates salt tolerance of Arabidopsis in abscisic acid-dependent manner

Energy Technology Data Exchange (ETDEWEB)

Liu, Xin, E-mail: fangfei6073@126.com [Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin 150030 (China); Zhu, Yanming, E-mail: ymzhu2001@neau.edu.cn [Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin 150030 (China); Zhai, Hong, E-mail: Zhai.h@neigaehrb.ac.cn [Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin 150040 (China); Cai, Hua, E-mail: small-big@sohu.com [Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin 150030 (China); Ji, Wei, E-mail: iwei_j@hotmail.com [Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin 150030 (China); Luo, Xiao, E-mail: luoxiao2010@yahoo.cn [Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin 150030 (China); Li, Jing, E-mail: lijing@neau.edu.cn [Plant Secondary Metabolism Laboratory, Northeast Agricultural University, Harbin 150030 (China); Bai, Xi, E-mail: baixi@neau.edu.cn [Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin 150030 (China)

2012-06-15

Highlights: Black-Right-Pointing-Pointer AtPP2CG1 positively regulates salt tolerance in ABA-dependent manner. Black-Right-Pointing-Pointer AtPP2CG1 up-regulates the expression of marker genes in different pathways. Black-Right-Pointing-Pointer AtPP2CG1 expresses in the vascular system and trichomes of Arabidopsis. -- Abstract: AtPP2CG1 (Arabidopsis thaliana protein phosphatase 2C G Group 1) was predicted as an abiotic stress candidate gene by bioinformatic analysis in our previous study. The gene encodes a putative protein phosphatase 2C that belongs to Group G of PP2C. There is no report of Group G genes involved in abiotic stress so far. Real-time RT-PCR analysis showed that AtPP2CG1 expression was induced by salt, drought, and abscisic acid (ABA) treatment. The expression levels of AtPP2CG1 in the ABA synthesis-deficient mutant abi2-3 were much lower than that in WT plants under salt stress suggesting that the expression of AtPP2CG1 acts in an ABA-dependent manner. Over-expression of AtPP2CG1 led to enhanced salt tolerance, whereas its loss of function caused decreased salt tolerance. These results indicate that AtPP2CG1 positively regulates salt stress in an ABA-dependent manner. Under salt treatment, AtPP2CG1 up-regulated the expression levels of stress-responsive genes, including RD29A, RD29B, DREB2A and KIN1. GUS activity was detected in roots, leaves, stems, flower, and trichomes of AtPP2CG1 promoter-GUS transgenic plants. AtPP2CG1 protein was localized in nucleus and cytoplasm via AtPP2CG1:eGFP and YFP:AtPP2CG1 fusion approaches.

FIN5 positively regulates far-red light responses in Arabidopsis thaliana

International Nuclear Information System (INIS)

Cho, D.S.; Hong, S.H.; Nam, H.G.; Soh, M.S.

2003-01-01

We report the characterization of a semi-dominant mutation fin5-1 (far-red insensitive 5-1) of Arabidopsis, which was isolated from genetic screening of phytochrome A (phyA) signaling components. Plants with the fin5-1 mutation exhibited a long hypocotyl phenotype when grown under far-red (FR) light, but not under red light. Physiological analyses implied that FIN5 might be differentially involved in diverse responses that are regulated by phyA under continuous FR light. Anthocyanin accumulation, gravitropic response of hypocotyl growth, and FR light-preconditioned blocking of greening were also impaired in the fin5-1 mutant, whereas photoperiodic floral induction was not, if at all, significantly affected. Moreover, light-regulated expression of the CHS, PORA and PsbS genes was attenuated in fin5-1 mutant plants, while the light-induced expression of CAB was normal. The mutation exhibited semi-dominance regarding control of hypocotyl growth in FR light. We suggest that FIN5 defines a novel branch in the network of phyA signaling in Arabidopsis. (author)

Arabidopsis VARIEGATED 3 encodes a chloroplast-targeted, zinc-finger protein required for chloroplast and palisade cell development

DEFF Research Database (Denmark)

Næsted, Henrik; Holm, Agnethe; Jenkins, Tom

2004-01-01

The stable, recessive Arabidopsis variegated 3 (var3) mutant exhibits a variegated phenotype due to somatic areas lacking or containing developmentally retarded chloroplasts and greatly reduced numbers of palisade cells. The VAR3 gene, isolated by transposon tagging, encodes the 85.9 kDa VAR3...... that pigment profiles are qualitatively similar in wild type and var3, although var3 accumulates lower levels of chlorophylls and carotenoids. These results indicate that VAR3 is a part of a protein complex required for normal chloroplast and palisade cell development....

Analysis of essential Arabidopsis nuclear genes encoding plastid-targeted proteins.

Science.gov (United States)

Savage, Linda J; Imre, Kathleen M; Hall, David A; Last, Robert L

2013-01-01

The Chloroplast 2010 Project (http://www.plastid.msu.edu/) identified and phenotypically characterized homozygous mutants in over three thousand genes, the majority of which encode plastid-targeted proteins. Despite extensive screening by the community, no homozygous mutant alleles were available for several hundred genes, suggesting that these might be enriched for genes of essential function. Attempts were made to generate homozygotes in ~1200 of these lines and 521 of the homozygous viable lines obtained were deposited in the Arabidopsis Biological Resource Center (http://abrc.osu.edu/). Lines that did not yield a homozygote in soil were tested as potentially homozygous lethal due to defects either in seed or seedling development. Mutants were characterized at four stages of development: developing seed, mature seed, at germination, and developing seedlings. To distinguish seed development or seed pigment-defective mutants from seedling development mutants, development of seeds was assayed in siliques from heterozygous plants. Segregating seeds from heterozygous parents were sown on supplemented media in an attempt to rescue homozygous seedlings that could not germinate or survive in soil. Growth of segregating seeds in air and air enriched to 0.3% carbon dioxide was compared to discover mutants potentially impaired in photorespiration or otherwise responsive to CO2 supplementation. Chlorophyll fluorescence measurements identified CO2-responsive mutants with altered photosynthetic parameters. Examples of genes with a viable mutant allele and one or more putative homozygous-lethal alleles were documented. RT-PCR of homozygotes for potentially weak alleles revealed that essential genes may remain undiscovered because of the lack of a true null mutant allele. This work revealed 33 genes with two or more lethal alleles and 73 genes whose essentiality was not confirmed with an independent lethal mutation, although in some cases second leaky alleles were identified.

Analysis of essential Arabidopsis nuclear genes encoding plastid-targeted proteins.

Directory of Open Access Journals (Sweden)

Linda J Savage

Full Text Available The Chloroplast 2010 Project (http://www.plastid.msu.edu/ identified and phenotypically characterized homozygous mutants in over three thousand genes, the majority of which encode plastid-targeted proteins. Despite extensive screening by the community, no homozygous mutant alleles were available for several hundred genes, suggesting that these might be enriched for genes of essential function. Attempts were made to generate homozygotes in ~1200 of these lines and 521 of the homozygous viable lines obtained were deposited in the Arabidopsis Biological Resource Center (http://abrc.osu.edu/. Lines that did not yield a homozygote in soil were tested as potentially homozygous lethal due to defects either in seed or seedling development. Mutants were characterized at four stages of development: developing seed, mature seed, at germination, and developing seedlings. To distinguish seed development or seed pigment-defective mutants from seedling development mutants, development of seeds was assayed in siliques from heterozygous plants. Segregating seeds from heterozygous parents were sown on supplemented media in an attempt to rescue homozygous seedlings that could not germinate or survive in soil. Growth of segregating seeds in air and air enriched to 0.3% carbon dioxide was compared to discover mutants potentially impaired in photorespiration or otherwise responsive to CO2 supplementation. Chlorophyll fluorescence measurements identified CO2-responsive mutants with altered photosynthetic parameters. Examples of genes with a viable mutant allele and one or more putative homozygous-lethal alleles were documented. RT-PCR of homozygotes for potentially weak alleles revealed that essential genes may remain undiscovered because of the lack of a true null mutant allele. This work revealed 33 genes with two or more lethal alleles and 73 genes whose essentiality was not confirmed with an independent lethal mutation, although in some cases second leaky alleles

Changes in Gene Expression of Arabidopsis Thaliana Cell Cultures Upon Exposure to Real and Simulated Partial- g Forces

Science.gov (United States)

Fengler, Svenja; Spirer, Ina; Neef, Maren; Ecke, Margret; Hauslage, Jens; Hampp, Rüdiger

2016-06-01

Cell cultures of the plant model organism Arabidopsis thaliana were exposed to partial- g forces during parabolic flight and clinostat experiments (0.16 g, 0.38 g and 0.5 g were tested). In order to investigate gravity-dependent alterations in gene expression, samples were metabolically quenched by the fixative RNA later Ⓡ to stabilize nucleic acids and used for whole-genome microarray analysis. An attempt to identify the potential threshold acceleration for the gravity-dependent response showed that the smaller the experienced g-force, the greater was the susceptibility of the cell cultures. Compared to short-term μ g during a parabolic flight, the number of differentially expressed genes under partial- g was lower. In addition, the effect on the alteration of amounts of transcripts decreased during partial- g parabolic flight due to the sequence of the different parabolas (0.38 g, 0.16 g and μ g). A time-dependent analysis under simulated 0.5 g indicates that adaptation occurs within minutes. Differentially expressed genes (at least 2-fold up- or down-regulated in expression) under real flight conditions were to some extent identical with those affected by clinorotation. The highest number of homologuous genes was detected within seconds of exposure to 0.38 g (both flight and clinorotation). To a considerable part, these genes deal with cell wall properties. Additionally, responses specific for clinorotation were observed.

Arabidopsis CDS blastp result: AK102133 [KOME

Lifescience Database Archive (English)

Full Text Available AK102133 J033085E13 At5g43560.2 meprin and TRAF homology domain-containing protein / MATH... domain-containing protein weak similarity to ubiquitin-specific protease 12 [Arabidopsis thaliana] GI:11993471; contains Pfam profile PF00917: MATH domain 1e-146 ...

Arabidopsis CDS blastp result: AK120871 [KOME

Lifescience Database Archive (English)

Full Text Available AK120871 J023026D19 At1g48900.1 signal recognition particle 54 kDa protein 3 / SRP5...4 (SRP-54C) identical to SP|P49967 Signal recognition particle 54 kDa protein 3 (SRP54) {Arabidopsis thaliana} 0.0 ...

Autoimmunity in Arabidopsis acd11 is mediated by epigenetic regulation of an immune receptor.

Directory of Open Access Journals (Sweden)

Kristoffer Palma

Full Text Available Certain pathogens deliver effectors into plant cells to modify host protein targets and thereby suppress immunity. These target modifications can be detected by intracellular immune receptors, or Resistance (R proteins, that trigger strong immune responses including localized host cell death. The accelerated cell death 11 (acd11 "lesion mimic" mutant of Arabidopsis thaliana exhibits autoimmune phenotypes such as constitutive defense responses and cell death without pathogen perception. ACD11 encodes a putative sphingosine transfer protein, but its precise role during these processes is unknown. In a screen for lazarus (laz mutants that suppress acd11 death we identified two genes, LAZ2 and LAZ5. LAZ2 encodes the histone lysine methyltransferase SDG8, previously shown to epigenetically regulate flowering time via modification of histone 3 (H3. LAZ5 encodes an RPS4-like R-protein, defined by several dominant negative alleles. Microarray and chromatin immunoprecipitation analyses showed that LAZ2/SDG8 is required for LAZ5 expression and H3 lysine 36 trimethylation at LAZ5 chromatin to maintain a transcriptionally active state. We hypothesize that LAZ5 triggers cell death in the absence of ACD11, and that cell death in other lesion mimic mutants may also be caused by inappropriate activation of R genes. Moreover, SDG8 is required for basal and R protein-mediated pathogen resistance in Arabidopsis, revealing the importance of chromatin remodeling as a key process in plant innate immunity.

Ectopic overexpression of castor bean LEAFY COTYLEDON2 (LEC2 in Arabidopsis triggers the expression of genes that encode regulators of seed maturation and oil body proteins in vegetative tissues

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Hyun Uk Kim

2014-01-01

Full Text Available The LEAFY COTYLEDON2 (LEC2 gene plays critically important regulatory roles during both early and late embryonic development. Here, we report the identification of the LEC2 gene from the castor bean plant (Ricinus communis, and characterize the effects of its overexpression on gene regulation and lipid metabolism in transgenic Arabidopsis plants. LEC2 exists as a single-copy gene in castor bean, is expressed predominantly in embryos, and encodes a protein with a conserved B3 domain, but different N- and C-terminal domains to those found in LEC2 from Arabidopsis. Ectopic overexpression of LEC2 from castor bean under the control of the cauliflower mosaic virus (CaMV 35S promoter in Arabidopsis plants induces the accumulation of transcripts that encodes five major transcription factors (the LEAFY COTYLEDON1 (LEC1, LEAFY COTYLEDON1-LIKE (L1L, FUSCA3 (FUS3, and ABSCISIC ACID INSENSITIVE 3 (ABI3 transcripts for seed maturation, and WRINKELED1 (WRI1 transcripts for fatty acid biosynthesis, as well as OLEOSIN transcripts for the formation of oil bodies in vegetative tissues. Transgenic Arabidopsis plants that express the LEC2 gene from castor bean show a range of dose-dependent morphological phenotypes and effects on the expression of LEC2-regulated genes during seedling establishment and vegetative growth. Expression of castor bean LEC2 in Arabidopsis increased the expression of fatty acid elongase 1 (FAE1 and induced the accumulation of triacylglycerols, especially those containing the seed-specific fatty acid, eicosenoic acid (20:1Δ11, in vegetative tissues.

Ectopic overexpression of castor bean LEAFY COTYLEDON2 (LEC2) in Arabidopsis triggers the expression of genes that encode regulators of seed maturation and oil body proteins in vegetative tissues.

Science.gov (United States)

Kim, Hyun Uk; Jung, Su-Jin; Lee, Kyeong-Ryeol; Kim, Eun Ha; Lee, Sang-Min; Roh, Kyung Hee; Kim, Jong-Bum

2013-01-01

The LEAFY COTYLEDON2 (LEC2) gene plays critically important regulatory roles during both early and late embryonic development. Here, we report the identification of the LEC2 gene from the castor bean plant (Ricinus communis), and characterize the effects of its overexpression on gene regulation and lipid metabolism in transgenic Arabidopsis plants. LEC2 exists as a single-copy gene in castor bean, is expressed predominantly in embryos, and encodes a protein with a conserved B3 domain, but different N- and C-terminal domains to those found in LEC2 from Arabidopsis. Ectopic overexpression of LEC2 from castor bean under the control of the cauliflower mosaic virus (CaMV) 35S promoter in Arabidopsis plants induces the accumulation of transcripts that encodes five major transcription factors (the LEAFY COTYLEDON1 (LEC1), LEAFY COTYLEDON1-LIKE (L1L), FUSCA3 (FUS3), and ABSCISIC ACID INSENSITIVE 3 (ABI3) transcripts for seed maturation, and WRINKELED1 (WRI1) transcripts for fatty acid biosynthesis), as well as OLEOSIN transcripts for the formation of oil bodies in vegetative tissues. Transgenic Arabidopsis plants that express the LEC2 gene from castor bean show a range of dose-dependent morphological phenotypes and effects on the expression of LEC2-regulated genes during seedling establishment and vegetative growth. Expression of castor bean LEC2 in Arabidopsis increased the expression of fatty acid elongase 1 (FAE1) and induced the accumulation of triacylglycerols, especially those containing the seed-specific fatty acid, eicosenoic acid (20:1(Δ11)), in vegetative tissues.

Ectopic overexpression of castor bean LEAFY COTYLEDON2 (LEC2) in Arabidopsis triggers the expression of genes that encode regulators of seed maturation and oil body proteins in vegetative tissues☆

Science.gov (United States)

Kim, Hyun Uk; Jung, Su-Jin; Lee, Kyeong-Ryeol; Kim, Eun Ha; Lee, Sang-Min; Roh, Kyung Hee; Kim, Jong-Bum

2013-01-01

The LEAFY COTYLEDON2 (LEC2) gene plays critically important regulatory roles during both early and late embryonic development. Here, we report the identification of the LEC2 gene from the castor bean plant (Ricinus communis), and characterize the effects of its overexpression on gene regulation and lipid metabolism in transgenic Arabidopsis plants. LEC2 exists as a single-copy gene in castor bean, is expressed predominantly in embryos, and encodes a protein with a conserved B3 domain, but different N- and C-terminal domains to those found in LEC2 from Arabidopsis. Ectopic overexpression of LEC2 from castor bean under the control of the cauliflower mosaic virus (CaMV) 35S promoter in Arabidopsis plants induces the accumulation of transcripts that encodes five major transcription factors (the LEAFY COTYLEDON1 (LEC1), LEAFY COTYLEDON1-LIKE (L1L), FUSCA3 (FUS3), and ABSCISIC ACID INSENSITIVE 3 (ABI3) transcripts for seed maturation, and WRINKELED1 (WRI1) transcripts for fatty acid biosynthesis), as well as OLEOSIN transcripts for the formation of oil bodies in vegetative tissues. Transgenic Arabidopsis plants that express the LEC2 gene from castor bean show a range of dose-dependent morphological phenotypes and effects on the expression of LEC2-regulated genes during seedling establishment and vegetative growth. Expression of castor bean LEC2 in Arabidopsis increased the expression of fatty acid elongase 1 (FAE1) and induced the accumulation of triacylglycerols, especially those containing the seed-specific fatty acid, eicosenoic acid (20:1Δ11), in vegetative tissues. PMID:24363987

Arabidopsis CPR5 regulates ethylene signaling via molecular association with the ETR1 receptor.

Science.gov (United States)

Wang, Feifei; Wang, Lijuan; Qiao, Longfei; Chen, Jiacai; Pappa, Maria Belen; Pei, Haixia; Zhang, Tao; Chang, Caren; Dong, Chun-Hai

2017-11-01

The plant hormone ethylene plays various functions in plant growth, development and response to environmental stress. Ethylene is perceived by membrane-bound ethylene receptors, and among the homologous receptors in Arabidopsis, the ETR1 ethylene receptor plays a major role. The present study provides evidence demonstrating that Arabidopsis CPR5 functions as a novel ETR1 receptor-interacting protein in regulating ethylene response and signaling. Yeast split ubiquitin assays and bi-fluorescence complementation studies in plant cells indicated that CPR5 directly interacts with the ETR1 receptor. Genetic analyses indicated that mutant alleles of cpr5 can suppress ethylene insensitivity in both etr1-1 and etr1-2, but not in other dominant ethylene receptor mutants. Overexpression of Arabidopsis CPR5 either in transgenic Arabidopsis plants, or ectopically in tobacco, significantly enhanced ethylene sensitivity. These findings indicate that CPR5 plays a critical role in regulating ethylene signaling. CPR5 is localized to endomembrane structures and the nucleus, and is involved in various regulatory pathways, including pathogenesis, leaf senescence, and spontaneous cell death. This study provides evidence for a novel regulatory function played by CPR5 in the ethylene receptor signaling pathway in Arabidopsis. © 2017 Institute of Botany, Chinese Academy of Sciences.

Overexpression of the tonoplast aquaporin AtTIP5;1 conferred tolerance to boron toxicity in Arabidopsis.

Science.gov (United States)

Pang, Yongqi; Li, Lijuan; Ren, Fei; Lu, Pingli; Wei, Pengcheng; Cai, Jinghui; Xin, Lingguo; Zhang, Juan; Chen, Jia; Wang, Xuechen

2010-06-01

Boron (B) toxicity to plants is responsible for low crop productivity in many regions of the world. Here we report a novel and effective means to alleviate the B toxicity to plants under high B circumstance. Functional characterization of AtTIP5;1, an aquaporin gene, revealed that overexpression of AtTIP5;1 (OxAtTIP5;1) in Arabidopsis significantly increased its tolerance to high B toxicity. Compared to wild-type plants, OxAtTIP5;1 plants exhibited longer hypocotyls, accelerated development, increased silique production under high B treatments. GUS staining and quantitative RT-PCR (qRT-PCR) results demonstrated that the expression of AtTIP5;1 was induced by high B concentration treatment. Subcellular localization analysis revealed that the AtTIP5;1-GFP fusion protein was localized on the tonoplast membrane, which was consistent with the prediction based on bioinformatics. Taken together, our results suggest that AtTIP5;1 is involved in B transport pathway possibly via vacuolar compartmentation for B, and that overexpression of AtTIP5;1 in plants may provide an effective way to overcome the problem resulting from high B concentration toxicity. Copyright 2010 Institute of Genetics and Developmental Biology and the Genetics Society of China. Published by Elsevier Ltd. All rights reserved.

A compatible interaction of Alternaria brassicicola with Arabidopsis thaliana ecotype DiG: evidence for a specific transcriptional signature

Directory of Open Access Journals (Sweden)

Gepstein Shimon

2009-03-01

Full Text Available Abstract Background The interaction of Arabidopsis with Alternaria brassicicola provides a model for disease caused by necrotrophs, but a drawback has been the lack of a compatible pathosystem. Infection of most ecotypes, including the widely-studied line Col-0, with this pathogen generally leads to a lesion that does not expand beyond the inoculated area. This study examines an ecotype, Dijon G (DiG, which is considered sensitive to A. brassicicola. Results We show that the interaction has the characteristics of a compatible one, with expanding rather than limited lesions. To ask whether DiG is merely more sensitive to the pathogen or, rather, interacts in distinct manner, we identified genes whose regulation differs between Col-0 and DiG challenged with A. brassicicola. Suppression subtractive hybridization was used to identify differentially expressed genes, and their expression was verified using semi-quantitative PCR. We also tested a set of known defense-related genes for differential regulation in the two plant-pathogen interactions. Several known pathogenesis-related (PR genes are up-regulated in both interactions. PR1, and a monooxygenase gene identified in this study, MO1, are preferentially up-regulated in the compatible interaction. In contrast, GLIP1, which encodes a secreted lipase, and DIOX1, a pathogen-response related dioxygenase, are preferentially up-regulated in the incompatible interaction. Conclusion The results show that DiG is not only more susceptible, but demonstrate that its interaction with A. brassicicola has a specific transcriptional signature.

The Reaumuria trigyna transcription factor RtWRKY1 confers tolerance to salt stress in transgenic Arabidopsis.

Science.gov (United States)

Du, Chao; Zhao, Pingping; Zhang, Huirong; Li, Ningning; Zheng, Linlin; Wang, Yingchun

2017-08-01

Reaumuria trigyna (R. trigyna) is an endangered small shrub endemic to the Eastern Alxa-Western Ordos area in Inner Mongolia, China. Based on R. trigyna transcriptome data, the Group I WRKY transcription factor gene RtWRKY1 was cloned from R. trigyna. The full-length RtWRKY1 gene was 2100bp, including a 1261-bp open reading frame (ORF) encoding 573 amino acids. RtWRKY1 was mainly expressed in the stem and was induced by salt, cold stress, and ABA treatment. Overexpression of RtWRKY1 in Arabidopsis significantly enhanced the chlorophyll content, root length, and fresh weight of the transgenic lines under salt stress. RtWRKY1 transgenic Arabidopsis exhibited higher proline content, GSH-PX, POD, SOD, and CAT activities, and lower MDA content, Na + content, and Na + /K + ratio than wild-type Arabidopsis under salt stress conditions. Salt stress affected the expression of ion transport, proline biosynthesis, and antioxidant related genes, including AtAPX1, AtCAT1, AtSOD1, AtP5CS1, AtP5CS2, AtPRODH1, AtPRODH2, and AtSOS1 in transgenic lines. RtWRKY1 confers tolerance to salt stress in transgenic Arabidopsis by regulating plant growth, osmotic balance, Na + /K + homeostasis, and the antioxidant system. Copyright © 2017 Elsevier GmbH. All rights reserved.

The arabidopsis thaliana AGRAVITROPIC 1 gene encodes a component of the polar-auxin-transport efflux carrier

Science.gov (United States)

Chen, R.; Hilson, P.; Sedbrook, J.; Rosen, E.; Caspar, T.; Masson, P. H.

1998-01-01

Auxins are plant hormones that mediate many aspects of plant growth and development. In higher plants, auxins are polarly transported from sites of synthesis in the shoot apex to their sites of action in the basal regions of shoots and in roots. Polar auxin transport is an important aspect of auxin functions and is mediated by cellular influx and efflux carriers. Little is known about the molecular identity of its regulatory component, the efflux carrier [Estelle, M. (1996) Current Biol. 6, 1589-1591]. Here we show that mutations in the Arabidopsis thaliana AGRAVITROPIC 1 (AGR1) gene involved in root gravitropism confer increased root-growth sensitivity to auxin and decreased sensitivity to ethylene and an auxin transport inhibitor, and cause retention of exogenously added auxin in root tip cells. We used positional cloning to show that AGR1 encodes a putative transmembrane protein whose amino acid sequence shares homologies with bacterial transporters. When expressed in Saccharomyces cerevisiae, AGR1 promotes an increased efflux of radiolabeled IAA from the cells and confers increased resistance to fluoro-IAA, a toxic IAA-derived compound. AGR1 transcripts were localized to the root distal elongation zone, a region undergoing a curvature response upon gravistimulation. We have identified several AGR1-related genes in Arabidopsis, suggesting a global role of this gene family in the control of auxin-regulated growth and developmental processes.

Arabidopsis CDS blastp result: AK062262 [KOME

Lifescience Database Archive (English)

Full Text Available AK062262 001-047-H04 At5g13630.1 magnesium-chelatase subunit chlH, chloroplast, put...ative / Mg-protoporphyrin IX chelatase, putative (CHLH) nearly identical to magnesium chelatase subunit GI:1...154627 from [Arabidopsis thaliana]; contains Pfam profile: PF02514 CobN/magnesium chelatase family protein 0.0 ...

Arabidopsis CDS blastp result: AK069545 [KOME

Lifescience Database Archive (English)

Full Text Available AK069545 J023025I06 At5g13630.1 magnesium-chelatase subunit chlH, chloroplast, puta...tive / Mg-protoporphyrin IX chelatase, putative (CHLH) nearly identical to magnesium chelatase subunit GI:11...54627 from [Arabidopsis thaliana]; contains Pfam profile: PF02514 CobN/magnesium chelatase family protein 0.0 ...

Arabidopsis CDS blastp result: AK067323 [KOME

Lifescience Database Archive (English)

Full Text Available AK067323 J013106B16 At5g13630.1 magnesium-chelatase subunit chlH, chloroplast, puta...tive / Mg-protoporphyrin IX chelatase, putative (CHLH) nearly identical to magnesium chelatase subunit GI:11...54627 from [Arabidopsis thaliana]; contains Pfam profile: PF02514 CobN/magnesium chelatase family protein 0.0 ...

Arabidopsis CDS blastp result: AK060612 [KOME

Lifescience Database Archive (English)

Full Text Available AK060612 001-025-F03 At5g13630.1 magnesium-chelatase subunit chlH, chloroplast, put...ative / Mg-protoporphyrin IX chelatase, putative (CHLH) nearly identical to magnesium chelatase subunit GI:1...154627 from [Arabidopsis thaliana]; contains Pfam profile: PF02514 CobN/magnesium chelatase family protein 0.0 ...

The Arabidopsis thaliana REDUCED EPIDERMAL FLUORESCENCE1 gene encodes an aldehyde dehydrogenase involved in ferulic acid and sinapic acid biosynthesis.

Science.gov (United States)

Nair, Ramesh B; Bastress, Kristen L; Ruegger, Max O; Denault, Jeff W; Chapple, Clint

2004-02-01

Recent research has significantly advanced our understanding of the phenylpropanoid pathway but has left in doubt the pathway by which sinapic acid is synthesized in plants. The reduced epidermal fluorescence1 (ref1) mutant of Arabidopsis thaliana accumulates only 10 to 30% of the sinapate esters found in wild-type plants. Positional cloning of the REF1 gene revealed that it encodes an aldehyde dehydrogenase, a member of a large class of NADP(+)-dependent enzymes that catalyze the oxidation of aldehydes to their corresponding carboxylic acids. Consistent with this finding, extracts of ref1 leaves exhibit low sinapaldehyde dehydrogenase activity. These data indicate that REF1 encodes a sinapaldehyde dehydrogenase required for sinapic acid and sinapate ester biosynthesis. When expressed in Escherichia coli, REF1 was found to exhibit both sinapaldehyde and coniferaldehyde dehydrogenase activity, and further phenotypic analysis of ref1 mutant plants showed that they contain less cell wall-esterified ferulic acid. These findings suggest that both ferulic acid and sinapic acid are derived, at least in part, through oxidation of coniferaldehyde and sinapaldehyde. This route is directly opposite to the traditional representation of phenylpropanoid metabolism in which hydroxycinnamic acids are instead precursors of their corresponding aldehydes.

Arabidopsis CDS blastp result: AK104855 [KOME

Lifescience Database Archive (English)

Full Text Available AK104855 001-043-B11 At5g54190.1 protochlorophyllide reductase A, chloroplast / PCR A / NADPH-protochlorophy...llide oxidoreductase A (PORA) identical to SP:Q42536 protochlorophyllide reductase ...A, chloroplast precursor (EC 1.3.1.33) (PCR A) (NADPH-protochlorophyllide oxidoreductase A) (POR A) [Arabidopsis thaliana] 1e-130 ...

Arabidopsis CDS blastp result: AK065420 [KOME

Lifescience Database Archive (English)

Full Text Available AK065420 J013022D10 At5g13630.1 magnesium-chelatase subunit chlH, chloroplast, puta...tive / Mg-protoporphyrin IX chelatase, putative (CHLH) nearly identical to magnesium chelatase subunit GI:11...54627 from [Arabidopsis thaliana]; contains Pfam profile: PF02514 CobN/magnesium chelatase family protein 1e-166 ...

Arabidopsis CPR5 is a senescence-regulatory gene with pleiotropic functions as predicted by the evolutionary theory of senescence

NARCIS (Netherlands)

Jing, Hai-Chun; Anderson, Lisa; Sturre, Marcel J. G.; Hille, Jacques; Dijkwel, Paul P.

2007-01-01

Arabidopsis CPR5 is a senescence-regulatory gene with pleiotropic functions as predicted by the evolutionary theory of senescence Hai-Chun Jing1,2, Lisa Anderson3, Marcel J.G. Sturre1, Jacques Hille1 and Paul P. Dijkwel1,* 1Molecular Biology of Plants, Groningen Biomolecular Sciences and

Intergenic sequence between Arabidopsis caseinolytic protease B-cytoplasmic/heat shock protein100 and choline kinase genes functions as a heat-inducible bidirectional promoter.

Science.gov (United States)

Mishra, Ratnesh Chandra; Grover, Anil

2014-11-01

In Arabidopsis (Arabidopsis thaliana), the At1g74310 locus encodes for caseinolytic protease B-cytoplasmic (ClpB-C)/heat shock protein100 protein (AtClpB-C), which is critical for the acquisition of thermotolerance, and At1g74320 encodes for choline kinase (AtCK2) that catalyzes the first reaction in the Kennedy pathway for phosphatidylcholine biosynthesis. Previous work has established that the knockout mutants of these genes display heat-sensitive phenotypes. While analyzing the AtClpB-C promoter and upstream genomic regions in this study, we noted that AtClpB-C and AtCK2 genes are head-to-head oriented on chromosome 1 of the Arabidopsis genome. Expression analysis showed that transcripts of these genes are rapidly induced in response to heat stress treatment. In stably transformed Arabidopsis plants harboring this intergenic sequence between head-to-head oriented green fluorescent protein and β-glucuronidase reporter genes, both transcripts and proteins of the two reporters were up-regulated upon heat stress. Four heat shock elements were noted in the intergenic region by in silico analysis. In the homozygous transfer DNA insertion mutant Salk_014505, 4,393-bp transfer DNA is inserted at position -517 upstream of ATG of the AtClpB-C gene. As a result, AtCk2 loses proximity to three of the four heat shock elements in the mutant line. Heat-inducible expression of the AtCK2 transcript was completely lost, whereas the expression of AtClpB-C was not affected in the mutant plants. Our results suggest that the 1,329-bp intergenic fragment functions as a heat-inducible bidirectional promoter and the region governing the heat inducibility is possibly shared between the two genes. We propose a model in which AtClpB-C shares its regulatory region with heat-induced choline kinase, which has a possible role in heat signaling. © 2014 American Society of Plant Biologists. All Rights Reserved.

Phytochrome-interacting factors PIF4 and PIF5 negatively regulate anthocyanin biosynthesis under red light in Arabidopsis seedlings.

Science.gov (United States)

Liu, Zhongjuan; Zhang, Yongqiang; Wang, Jianfeng; Li, Ping; Zhao, Chengzhou; Chen, Yadi; Bi, Yurong

2015-09-01

Light is an important environmental factor inducing anthocyanin accumulation in plants. Phytochrome-interacting factors (PIFs) have been shown to be a family of bHLH transcription factors involved in light signaling in Arabidopsis. Red light effectively increased anthocyanin accumulation in wild-type Col-0, whereas the effects were enhanced in pif4 and pif5 mutants but impaired in overexpression lines PIF4OX and PIF5OX, indicating that PIF4 and PIF5 are both negative regulators for red light-induced anthocyanin accumulation. Consistently, transcript levels of several genes involved in anthocyanin biosynthesis and regulatory pathway, including CHS, F3'H, DFR, LDOX, PAP1 and TT8, were significantly enhanced in mutants pif4 and pif5 but decreased in PIF4OX and PIF5OX compared to in Col-0, indicating that PIF4 and PIF5 are transcriptional repressor of these gene. Transient expression assays revealed that PIF4 and PIF5 could repress red light-induced promoter activities of F3'H and DFR in Arabidopsis protoplasts. Furthermore, chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) test and electrophoretic mobility shift assay (EMSA) showed that PIF5 could directly bind to G-box motifs present in the promoter of DFR. Taken together, these results suggest that PIF4 and PIF5 negatively regulate red light-induced anthocyanin accumulation through transcriptional repression of the anthocyanin biosynthetic genes in Arabidopsis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Arabidopsis CDS blastp result: AK065950 [KOME

Lifescience Database Archive (English)

Full Text Available AK065950 J013049M07 At3g11820.1 syntaxin 121 (SYP121) / syntaxin-related protein (S...YR1) contains Pfam profiles: PF00804 syntaxin and PF05739: SNARE domain; identical to cDNA syntaxin-related ...protein At-SYR1 (At-Syr1) GI:4206788, SP|Q9ZSD4 Syntaxin 121 (AtSYP121) (Syntaxin-related protein At-Syr1) {Arabidopsis thaliana} 5e-88 ...

Arabidopsis ACA7, encoding a putative auto-regulated Ca(2+)-ATPase, is required for normal pollen development.

Science.gov (United States)

Lucca, Noel; León, Gabriel

2012-04-01

Microgametogenesis is a complex process that involves numerous well-coordinated cell activities, ending with the production of pollen grains. Pollen development has been studied at the cytological level in Arabidopsis and other plant species, where its temporal time course has been defined. However, the molecular mechanism underlying this process is still unclear, since a relative small number of genes and/or processes have been identified as essential for pollen development. We have designed a methodology to select candidate genes for functional analysis, based on transcriptomic data obtained from different stages of pollen development. From our analyses, we selected At2g22950 as a candidate gene; this gene encodes a protein belonging to the auto-regulated Ca(2+)-ATPase family, ACA7. Microarray data indicate that ACA7 is expressed exclusively in developing pollen grains, with the highest level of mRNA at the time of the second pollen mitosis. Our RT-PCR experiments showed that ACA7 mRNA is detected exclusively in developing flowers. Confocal microscopy experiments showed a plasma membrane localization for the recombinant GFP:ACA7 protein. We identified two different insertional mutant lines, aca7-1 and aca7-2; plants from both mutant lines displayed a normal vegetative development but showed large amounts of dead pollen grains in mature flowers assayed by Alexander's staining. Histological analysis indicated that abnormalities are detected after the first pollen mitosis and we found a strong correlation between ACA7 mRNA accumulation and the severity of the phenotype. Our results indicate that ACA7 is a plasma membrane protein that has an important role during pollen development, possibly through regulation of Ca(2+) homeostasis. © Springer-Verlag 2011

NKS1, Na+- and K+-sensitive 1, regulates ion homeostasis in an SOS-independent pathway in Arabidopsis

KAUST Repository

Choi, Wonkyun

2011-04-01

An Arabidopsis thaliana mutant, nks1-1, exhibiting enhanced sensitivity to NaCl was identified in a screen of a T-DNA insertion population in the genetic background of Col-0 gl1 sos3-1. Analysis of the genome sequence in the region flanking the T-DNA left border indicated two closely linked mutations in the gene encoded at locus At4g30996. A second allele, nks1-2, was obtained from the Arabidopsis Biological Resource Center. NKS1 mRNA was detected in all parts of wild-type plants but was not detected in plants of either mutant, indicating inactivation by the mutations. Both mutations in NKS1 were associated with increased sensitivity to NaCl and KCl, but not to LiCl or mannitol. NaCl sensitivity was associated with nks1 mutations in Arabidopsis lines expressing either wild type or alleles of SOS1, SOS2 or SOS3. The NaCl-sensitive phenotype of the nks1-2 mutant was complemented by expression of a full-length NKS1 allele from the CaMV35S promoter. When grown in medium containing NaCl, nks1 mutants accumulated more Na+ than wild type and K +/Na+ homeostasis was perturbed. It is proposed NKS1, a plant-specific gene encoding a 19 kDa endomembrane-localized protein of unknown function, is part of an ion homeostasis regulation pathway that is independent of the SOS pathway. © 2011 Elsevier Ltd. All rights reserved.

NKS1, Na+- and K+-sensitive 1, regulates ion homeostasis in an SOS-independent pathway in Arabidopsis

KAUST Repository

Choi, Wonkyun; Baek, Dongwon; Oh, Dongha; Park, Jiyoung; Hong, Hyewon; Kim, Woeyeon; Bohnert, Hans Jü rgen; Bressan, Ray Anthony; Park, Hyeongcheol; Yun, Daejin

2011-01-01

An Arabidopsis thaliana mutant, nks1-1, exhibiting enhanced sensitivity to NaCl was identified in a screen of a T-DNA insertion population in the genetic background of Col-0 gl1 sos3-1. Analysis of the genome sequence in the region flanking the T-DNA left border indicated two closely linked mutations in the gene encoded at locus At4g30996. A second allele, nks1-2, was obtained from the Arabidopsis Biological Resource Center. NKS1 mRNA was detected in all parts of wild-type plants but was not detected in plants of either mutant, indicating inactivation by the mutations. Both mutations in NKS1 were associated with increased sensitivity to NaCl and KCl, but not to LiCl or mannitol. NaCl sensitivity was associated with nks1 mutations in Arabidopsis lines expressing either wild type or alleles of SOS1, SOS2 or SOS3. The NaCl-sensitive phenotype of the nks1-2 mutant was complemented by expression of a full-length NKS1 allele from the CaMV35S promoter. When grown in medium containing NaCl, nks1 mutants accumulated more Na+ than wild type and K +/Na+ homeostasis was perturbed. It is proposed NKS1, a plant-specific gene encoding a 19 kDa endomembrane-localized protein of unknown function, is part of an ion homeostasis regulation pathway that is independent of the SOS pathway. © 2011 Elsevier Ltd. All rights reserved.

Evidence for a Ustilago maydis Steroid 5α-Reductase by Functional Expression in Arabidopsis det2-1 Mutants1

Science.gov (United States)

Basse, Christoph W.; Kerschbamer, Christine; Brustmann, Markus; Altmann, Thomas; Kahmann, Regine

2002-01-01

We have identified a gene (udh1) in the basidiomycete Ustilago maydis that is induced during the parasitic interaction with its host plant maize (Zea mays). udh1 encodes a protein with high similarity to mammalian and plant 5α-steroid reductases. Udh1 differs from those of known 5α-steroid reductases by six additional domains, partially predicted to be membrane-spanning. A fusion protein of Udh1 and the green fluorescent protein provided evidence for endoplasmic reticulum localization in U. maydis. The function of the Udh1 protein was demonstrated by complementing Arabidopsis det2-1 mutants, which display a dwarf phenotype due to a mutation in the 5α-steroid reductase encoding DET2 gene. det2-1 mutant plants expressing either the udh1 or the DET2 gene controlled by the cauliflower mosaic virus 35S promoter differed from wild-type Columbia plants by accelerated stem growth, flower and seed development and a reduction in size and number of rosette leaves. The accelerated growth phenotype of udh1 transgenic plants was stably inherited and was favored under reduced light conditions. Truncation of the N-terminal 70 amino acids of the Udh1 protein abolished the ability to restore growth in det2-1 plants. Our results demonstrate the existence of a 5α-steroid reductase encoding gene in fungi and suggest a common ancestor between fungal, plant, and mammalian proteins. PMID:12068114

The high affinity K+ transporter AtHAK5 plays a physiological role in planta at very low K+ concentrations and provides a caesium uptake pathway in Arabidopsis.

Science.gov (United States)

Qi, Zhi; Hampton, Corrina R; Shin, Ryoung; Barkla, Bronwyn J; White, Philip J; Schachtman, Daniel P

2008-01-01

Caesium (Cs(+)) is a potentially toxic mineral element that is released into the environment and taken up by plants. Although Cs(+) is chemically similar to potassium (K(+)), and much is known about K(+) transport mechanisms, it is not clear through which K(+) transport mechanisms Cs(+) is taken up by plant roots. In this study, the role of AtHAK5 in high affinity K(+) and Cs(+) uptake was characterized. It is demonstrated that AtHAK5 is localized to the plasma membrane under conditions of K(+) deprivation, when it is expressed. Growth analysis showed that AtHAK5 plays a role during severe K(+) deprivation. Under K(+)-deficient conditions in the presence of Cs(+), Arabidopsis seedlings lacking AtHAK5 had increased inhibition of root growth and lower Cs(+) accumulation, and significantly higher leaf chlorophyll concentrations than wild type. These data indicate that, in addition to transporting K(+) in planta, AtHAK5 also transports Cs(+). Further experiments showed that AtHAK5 mediated Cs(+) uptake into yeast cells and that, although the K(+) deficiency-induced expression of AtHAK5 was inhibited by low concentrations of NH(4)(+) in planta, Cs(+) uptake by yeast was stimulated by low concentrations of NH(4)(+). Interestingly, the growth of the Arabidopsis atakt1-1 mutant was more sensitive to Cs(+) than the wild type. This may be explained, in part, by increased expression of AtHAK5 in the atakt1-1 mutant. It is concluded that AtHAK5 is a root plasma membrane uptake mechanism for K(+) and Cs(+) under conditions of low K(+) availability.

Reference: 278 [Arabidopsis Phenome Database[Archive

Lifescience Database Archive (English)

Full Text Available functional ERA1 gene, which encodes the beta-subunit of protein farnesyltransferase (PFT), exhibit pleiotropic effects...gnaling and meristem development. Here, we report the effects of T-DNA insertion mutations in the Arabidopsi

Dynamic regulation of genome-wide pre-mRNA splicing and stress tolerance by the Sm-like protein LSm5 in Arabidopsis

KAUST Repository

Cui, Peng

2014-01-07

Background: Sm-like proteins are highly conserved proteins that form the core of the U6 ribonucleoprotein and function in several mRNA metabolism processes, including pre-mRNA splicing. Despite their wide occurrence in all eukaryotes, little is known about the roles of Sm-like proteins in the regulation of splicing.Results: Here, through comprehensive transcriptome analyses, we demonstrate that depletion of the Arabidopsis supersensitive to abscisic acid and drought 1 gene (SAD1), which encodes Sm-like protein 5 (LSm5), promotes an inaccurate selection of splice sites that leads to a genome-wide increase in alternative splicing. In contrast, overexpression of SAD1 strengthens the precision of splice-site recognition and globally inhibits alternative splicing. Further, SAD1 modulates the splicing of stress-responsive genes, particularly under salt-stress conditions. Finally, we find that overexpression of SAD1 in Arabidopsis improves salt tolerance in transgenic plants, which correlates with an increase in splicing accuracy and efficiency for stress-responsive genes.Conclusions: We conclude that SAD1 dynamically controls splicing efficiency and splice-site recognition in Arabidopsis, and propose that this may contribute to SAD1-mediated stress tolerance through the metabolism of transcripts expressed from stress-responsive genes. Our study not only provides novel insights into the function of Sm-like proteins in splicing, but also uncovers new means to improve splicing efficiency and to enhance stress tolerance in a higher eukaryote. 2014 Cui et al.; licensee BioMed Central Ltd.

Single nucleotide polymorphism analysis of ubiquitin extension protein genes (ubq) of gossypium arboreum and gossypium herbaceum in comparison with arabidopsis thaliana

International Nuclear Information System (INIS)

Shaheen, T.; Zafar, Y.; Rahman, M.

2014-01-01

Single nucleotide polymorphism analysis is an expedient way to study polymorphisms at genomic level. In the present study we have explored Ubiquitin extension protein gene of G. arboreum (A2) and G. herbaceum (A1) of cotton which is a multiple copy gene. We have found SNPs at 16 positions in 200 bp region within A genome of cotton indicating frequency of SNPs 1/13 bp. Both sequences from cotton have shown maximum similarity with UBQ5 and UBQ6 of Arabidopsis thaliana. Sequence obtained from G. arboreum has shown SNPs at 28 positions in comparison with each UBQ5 and UBQ6 of Arabidopsis thaliana while sequence obtained from G. herbaceum has shown SNPs at 31 positions in comparison with each UBQ5 and UBQ6 of Arabidopsis thaliana. In conclusion although during pace of evolution ubiquitin extension protein genes of both A genome species have got some mutations from nature but still most of their sequence is similar. Single nucleotide polymorphism study can prove a vital tool to identify gene type in case of Multicopy genes. (author)

Nucleotide variation in ATHK1 region of Arabidopsis thaliana and its ...

African Journals Online (AJOL)

The ATHK1 gene in Arabidopsis encodes a putative histidine kinase that is transcriptionally upregulated in response to changes in external osmolarity. In this work, we investigated the nucleotide variability of the ATHK1 gene in a sample of 32 core Arabidopsis accessions originating from different ecoclimatic regions and ...

The AtCAO gene, encoding chlorophyll a oxygenase, is required for chlorophyll b synthesis in Arabidopsis thaliana

Science.gov (United States)

Espineda, Cromwell E.; Linford, Alicia S.; Devine, Domenica; Brusslan, Judy A.

1999-01-01

Chlorophyll b is synthesized from chlorophyll a and is found in the light-harvesting complexes of prochlorophytes, green algae, and both nonvascular and vascular plants. We have used conserved motifs from the chlorophyll a oxygenase (CAO) gene from Chlamydomonas reinhardtii to isolate a homologue from Arabidopsis thaliana. This gene, AtCAO, is mutated in both leaky and null chlorina1 alleles, and DNA sequence changes cosegregate with the mutant phenotype. AtCAO mRNA levels are higher in three different mutants that have reduced levels of chlorophyll b, suggesting that plants that do not have sufficient chlorophyll b up-regulate AtCAO gene expression. Additionally, AtCAO mRNA levels decrease in plants that are grown under dim-light conditions. We have also found that the six major Lhcb proteins do not accumulate in the null ch1-3 allele. PMID:10468639

Differentially expressed genes associated with dormancy or germination of Arabidopsis thaliana seeds

NARCIS (Netherlands)

Toorop, P.E.; Barroco, R.M.; Engler, G.; Groot, S.P.C.; Hilhorst, H.W.M.

2005-01-01

Differential display analysis using dormant and non-dormant Arabidopsis thaliana (L.) Heynh seeds resulted in a set of genes that were associated with either dormancy or germination. Expression of the germination-associated genes AtRPL36B and AtRPL27B, encoding two ribosomal proteins, was

Regulatory domain or CpG site variation in SLC12A5, encoding the chloride transporter KCC2, in human autism and schizophrenia

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Nancy D Merner

2015-10-01

Full Text Available Many encoded gene products responsible for neurodevelopmental disorders (NDs like autism spectrum disorders (ASD, schizophrenia (SCZ, intellectual disability (ID, and idiopathic generalized epilepsy (IGE converge on networks controlling synaptic function. An increase in KCC2 (SLC12A5 Cl- transporter activity drives the developmental GABA excitatory-inhibitory sequence, but the role of KCC2 in human NDs is essentially unknown. Here, we report two rare, non-synonymous (NS, functionally-impairing variants in the KCC2 C-terminal regulatory domain (CTRD in human ASD (R952H and R1049C and SCZ (R952H previously linked with IGE and familial febrile seizures, and another novel NS KCC2 variant in ASD (R1048W with highly-predicted pathogenicity. Exome data from 2517 simplex families in the ASD Simon Simplex Collection revealed significantly more KCC2 CTRD variants in ASD cases than controls, and interestingly, these were more often synonymous and predicted to disrupt or introduce a CpG site. Furthermore, full gene analysis showed ASD cases are more likely to contain rare KCC2 variants affecting CpG sites than controls. These data suggest genetically-encoded dysregulation of KCC2-dependent GABA signaling may contribute to multiple human NDs.

Glufosinate ammonium selection of transformed Arabidopsis.

Science.gov (United States)

Weigel, Detlef; Glazebrook, Jane

2006-12-01

INTRODUCTIONOne of the most commonly used markers for the selection of transgenic Arabidopsis is resistance to glufosinate ammonium, an herbicide that is sold under a variety of trade names including Basta and Finale. Resistance to glufosinate ammonium is conferred by the bacterial bialophos resistance gene (BAR) encoding the enzyme phosphinotricin acetyl transferase (PAT). This protocol describes the use of glufosinate ammonium to select transformed Arabidopsis plants. The major advantage of glufosinate ammonium selection is that it can be performed on plants growing in soil and does not require the use of sterile techniques.

A distal ABA responsive element in AtNCED3 promoter is required for positive feedback regulation of ABA biosynthesis in Arabidopsis.

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Yan-Zhuo Yang

Full Text Available The plant hormone abscisic acid (ABA plays a crucial role in plant development and responses to abiotic stresses. Recent studies indicate that a positive feedback regulation by ABA exists in ABA biosynthesis in plants under dehydration stress. To understand the molecular basis of this regulation, we analyzed the cis-elements of the AtNCED3 promoter in Arabidopsis. AtNCED3 encodes the first committed and highly regulated dioxygenase in the ABA biosynthetic pathway. Through delineated and mutagenesis analyses in stable-transformed Arabidopsis, we revealed that a distal ABA responsive element (ABRE: GGCACGTG, -2372 to -2364 bp is required for ABA-induced AtNCED3 expression. By analyzing the AtNCED3 expression in ABRE binding protein ABF3 over-expression transgenic plants and knock-out mutants, we provide evidence that the ABA feedback regulation of AtNCED3 expression is not mediated by ABF3.

A distal ABA responsive element in AtNCED3 promoter is required for positive feedback regulation of ABA biosynthesis in Arabidopsis.

Science.gov (United States)

Yang, Yan-Zhuo; Tan, Bao-Cai

2014-01-01

The plant hormone abscisic acid (ABA) plays a crucial role in plant development and responses to abiotic stresses. Recent studies indicate that a positive feedback regulation by ABA exists in ABA biosynthesis in plants under dehydration stress. To understand the molecular basis of this regulation, we analyzed the cis-elements of the AtNCED3 promoter in Arabidopsis. AtNCED3 encodes the first committed and highly regulated dioxygenase in the ABA biosynthetic pathway. Through delineated and mutagenesis analyses in stable-transformed Arabidopsis, we revealed that a distal ABA responsive element (ABRE: GGCACGTG, -2372 to -2364 bp) is required for ABA-induced AtNCED3 expression. By analyzing the AtNCED3 expression in ABRE binding protein ABF3 over-expression transgenic plants and knock-out mutants, we provide evidence that the ABA feedback regulation of AtNCED3 expression is not mediated by ABF3.

Chloroplast genomes of Arabidopsis halleri ssp. gemmifera and Arabidopsis lyrata ssp. petraea: Structures and comparative analysis.

Science.gov (United States)

Asaf, Sajjad; Khan, Abdul Latif; Khan, Muhammad Aaqil; Waqas, Muhammad; Kang, Sang-Mo; Yun, Byung-Wook; Lee, In-Jung

2017-08-08

We investigated the complete chloroplast (cp) genomes of non-model Arabidopsis halleri ssp. gemmifera and Arabidopsis lyrata ssp. petraea using Illumina paired-end sequencing to understand their genetic organization and structure. Detailed bioinformatics analysis revealed genome sizes of both subspecies ranging between 154.4~154.5 kbp, with a large single-copy region (84,197~84,158 bp), a small single-copy region (17,738~17,813 bp) and pair of inverted repeats (IRa/IRb; 26,264~26,259 bp). Both cp genomes encode 130 genes, including 85 protein-coding genes, eight ribosomal RNA genes and 37 transfer RNA genes. Whole cp genome comparison of A. halleri ssp. gemmifera and A. lyrata ssp. petraea, along with ten other Arabidopsis species, showed an overall high degree of sequence similarity, with divergence among some intergenic spacers. The location and distribution of repeat sequences were determined, and sequence divergences of shared genes were calculated among related species. Comparative phylogenetic analysis of the entire genomic data set and 70 shared genes between both cp genomes confirmed the previous phylogeny and generated phylogenetic trees with the same topologies. The sister species of A. halleri ssp. gemmifera is A. umezawana, whereas the closest relative of A. lyrata spp. petraea is A. arenicola.

Mutations in the Arabidopsis AtMRS2-11/AtMGT10/VAR5 Gene Cause Leaf Reticulation

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Shuang Liang

2017-11-01

Full Text Available In higher plants, the development of functional chloroplasts is essential for photosynthesis and many other physiological processes. With a long-term goal of elucidating the genetic regulation of chloroplast development, we identified two allelic leaf variegation mutants, variegated5-1 (var5-1 and var5-2. Both mutants showed a distinct leaf reticulation phenotype of yellow paraveinal regions and green interveinal regions, and the leaf reticulation phenotype correlated with photosynthetic defects. Through the identification of mutation sites in the two mutant alleles and the molecular complementation, we confirmed that VAR5 encodes a CorA family of Mg2+ transporters also known as AtMRS2-11/AtMGT10. Using protoplast transient expression and biochemical fractionation assays, we demonstrated that AtMRS2-11/AtMGT10/VAR5 likely localizes to the chloroplast envelope. Moreover, we established that AtMRS2-11/AtMGT10/VAR5 forms large molecular weight complexes in the chloroplast and the sizes of these complexes clearly exceed those of their bacterial counterparts, suggesting the compositions of CorA Mg2+ transporter complex is different between the chloroplast and bacteria. Our findings indicate that AtMRS2-11/AtMGT10/VAR5 plays an important role in the tissue specific regulation of chloroplast development.

Divided attention reduces resistance to distraction at encoding but not retrieval.

Science.gov (United States)

Weeks, Jennifer C; Hasher, Lynn

2017-08-01

Older adults show implicit memory for previously seen distraction, an effect attributed to poor attentional control. It is unclear whether this effect results from lack of control over encoding during the distraction task, lack of retrieval constraint during the test task, or both. In the present study, we simulated poor distraction control in young adults using divided attention at encoding, at retrieval, at both times, or not at all. The encoding task was a 1-back task on pictures with distracting superimposed letter strings, some of which were words. The retrieval task was a word fragment completion task testing implicit memory for the distracting words. Attention was divided using an auditory odd digit detection task. Dividing attention at encoding, but not at retrieval, resulted in significant priming for distraction, which suggests that control over encoding processes is a primary determinant of distraction transfer in populations with low inhibitory control (e.g. older adults).

Divergent regulation of Arabidopsis SAUR genes

NARCIS (Netherlands)

Mourik, van Hilda; Dijk, van Aalt D.J.; Stortenbeker, Niek; Angenent, Gerco C.; Bemer, Marian

2017-01-01

Background: Small Auxin-Upregulated RNA (SAUR) genes encode growth regulators that induce cell elongation. Arabidopsis contains more than 70 SAUR genes, of which the growth-promoting function has been unveiled in seedlings, while their role in other tissues remained largely unknown. Here, we

Arabidopsis CDS blastp result: AK108458 [KOME

Lifescience Database Archive (English)

Full Text Available AK108458 002-143-D05 At4g35000.1 L-ascorbate peroxidase 3 (APX3) identical to ascorbat...e peroxidase 3 [Arabidopsis thaliana] GI:2444019, L-ascorbate peroxidase [Arabidopsis thaliana] gi|152379...1|emb|CAA66926; similar to ascorbate peroxidase [Gossypium hirsutum] gi|1019946|gb|AAB52954 2e-35 ...

Arabidopsis CDS blastp result: AK070842 [KOME

Lifescience Database Archive (English)

Full Text Available AK070842 J023074O14 At4g35000.1 L-ascorbate peroxidase 3 (APX3) identical to ascorbat...e peroxidase 3 [Arabidopsis thaliana] GI:2444019, L-ascorbate peroxidase [Arabidopsis thaliana] gi|1523791...|emb|CAA66926; similar to ascorbate peroxidase [Gossypium hirsutum] gi|1019946|gb|AAB52954 1e-112 ...

AtMMS21, an SMC5/6 complex subunit, is involved in stem cell niche maintenance and DNA damage responses in Arabidopsis roots.

Science.gov (United States)

Xu, Panglian; Yuan, Dongke; Liu, Ming; Li, Chunxin; Liu, Yiyang; Zhang, Shengchun; Yao, Nan; Yang, Chengwei

2013-04-01

Plants maintain stem cells in meristems to sustain lifelong growth; these stem cells must have effective DNA damage responses to prevent mutations that can propagate to large parts of the plant. However, the molecular links between stem cell functions and DNA damage responses remain largely unexplored. Here, we report that the small ubiquitin-related modifier E3 ligase AtMMS21 (for methyl methanesulfonate sensitivity gene21) acts to maintain the root stem cell niche by mediating DNA damage responses in Arabidopsis (Arabidopsis thaliana). Mutation of AtMMS21 causes defects in the root stem cell niche during embryogenesis and postembryonic stages. AtMMS21 is essential for the proper expression of stem cell niche-defining transcription factors. Moreover, mms21-1 mutants are hypersensitive to DNA-damaging agents, have a constitutively increased DNA damage response, and have more DNA double-strand breaks (DSBs) in the roots. Also, mms21-1 mutants exhibit spontaneous cell death within the root stem cell niche, and treatment with DSB-inducing agents increases this cell death, suggesting that AtMMS21 is required to prevent DSB-induced stem cell death. We further show that AtMMS21 functions as a subunit of the STRUCTURAL MAINTENANCE OF CHROMOSOMES5/6 complex, an evolutionarily conserved chromosomal ATPase required for DNA repair. These data reveal that AtMMS21 acts in DSB amelioration and stem cell niche maintenance during Arabidopsis root development.

Arabidopsis thaliana RGXT1 and RGXT2 encode Golgi-localized (1,3)-alpha-D-xylosyltransferases involved in the synthesis of pectic rhamnogalacturonan-II

DEFF Research Database (Denmark)

Madsen, Jack Egelund; Petersen, Bent Larsen; Motawia, Mohammed Saddik

2006-01-01

in rhamnogalacturonan-II, a complex polysaccharide essential to vascular plants, and is conserved across higher plant families. Rhamnogalacturonan-II isolated from both RGXT1 and RGXT2 T-DNA insertional mutants functioned as specific acceptor molecules in the xylosyltransferase assay. Expression of RGXT1- and RGXT2......Two homologous plant-specific Arabidopsis thaliana genes, RGXT1 and RGXT2, belong to a new family of glycosyltransferases (CAZy GT-family-77) and encode cell wall (1,3)-alpha-d-xylosyltransferases. The deduced amino acid sequences contain single transmembrane domains near the N terminus, indicative...

A Novel Complementation Assay for Quick and Specific Screen of Genes Encoding Glycerol-3-Phosphate Acyltransferases

Directory of Open Access Journals (Sweden)

Jie Lei

2018-03-01

Full Text Available The initial step in glycerolipid biosynthesis, especially in diverse allopolyploid crop species, is poorly understood, mainly due to the lack of an effective and convenient method for functional characterization of genes encoding glycerol-3-phosphate acyltransferases (GPATs catalyzing this reaction. Here we present a novel complementation assay for quick and specific characterization of GPAT-encoding genes. Its key design involves rational construction of yeast conditional lethal gat1Δgat2Δ double mutant bearing the heterologous Arabidopsis AtGPAT1 gene whose leaky expression under repressed conditions does not support any non-specific growth, thereby circumventing the false positive problem encountered with the system based on the gat1Δgat2Δ mutant harboring the native episomal GAT1 gene whose leaky expression appears to be sufficient for generating enough GPAT activities for the non-specific restoration of the mutant growth. A complementation assay developed based on this novel mutant enables quick phenotypic screen of GPAT sequences. A high degree of specificity of our assay was exemplified by its ability to differentiate effectively GPAT-encoding genes from those of other fatty acyltransferases and lipid-related sequences. Using this assay, we show that Arabidopsis AtGPAT1, AtGPAT5, and AtGPAT7 can complement the phosphatidate biosynthetic defect in the double mutants. Collectively, our assay provides a powerful tool for rapid screening, validation and optimization of GPAT sequences, aiding future engineering of the initial step of the triacylglycerol biosynthesis in oilseeds.

Autoimmunity in Arabidopsis acd11 Is Mediated by Epigenetic Regulation of an Immune Receptor

DEFF Research Database (Denmark)

Palma, K.; Thorgrimsen, S.; Malinovsky, F.G.

2010-01-01

. In a screen for lazarus (laz) mutants that suppress acd11 death we identified two genes, LAZ2 and LAZ5. LAZ2 encodes the histone lysine methyltransferase SDG8, previously shown to epigenetically regulate flowering time via modification of histone 3 (H3). LAZ5 encodes an RPS4-like R-protein, defined by several...... dominant negative alleles. Microarray and chromatin immunoprecipitation analyses showed that LAZ2/SDG8 is required for LAZ5 expression and H3 lysine 36 trimethylation at LAZ5 chromatin to maintain a transcriptionally active state. We hypothesize that LAZ5 triggers cell death in the absence of ACD11......, and that cell death in other lesion mimic mutants may also be caused by inappropriate activation of R genes. Moreover, SDG8 is required for basal and R protein-mediated pathogen resistance in Arabidopsis, revealing the importance of chromatin remodeling as a key process in plant innate immunity....

Sorbitol dehydrogenase is a cytosolic protein required for sorbitol metabolism in Arabidopsis thaliana.

Science.gov (United States)

Aguayo, María Francisca; Ampuero, Diego; Mandujano, Patricio; Parada, Roberto; Muñoz, Rodrigo; Gallart, Marta; Altabella, Teresa; Cabrera, Ricardo; Stange, Claudia; Handford, Michael

2013-05-01

Sorbitol is converted to fructose in Rosaceae species by SORBITOL DEHYDROGENASE (SDH, EC 1.1.1.14), especially in sink organs. SDH has also been found in non-Rosaceae species and here we show that the protein encoded by At5g51970 in Arabidopsis thaliana (L.) Heynh. possesses the molecular characteristics of an SDH. Using a green fluorescent protein-tagged version and anti-SDH antisera, we determined that SDH is cytosolically localized, consistent with bioinformatic predictions. We also show that SDH is widely expressed, and that SDH protein accumulates in both source and sink organs. In the presence of NAD+, recombinant SDH exhibited greatest oxidative activity with sorbitol, ribitol and xylitol as substrates; other sugar alcohols were oxidized to a lesser extent. Under standard growth conditions, three independent sdh- mutants developed as wild-type. Nevertheless, all three exhibited reduced dry weight and primary root length compared to wild-type when grown in the presence of sorbitol. Additionally, under short-day conditions, the mutants were more resistant to dehydration stress, as shown by a reduced loss of leaf water content when watering was withheld, and a greater survival rate on re-watering. This evidence suggests that limitations in the metabolism of sugar alcohols alter the growth of Arabidopsis and its response to drought. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Intracellular localization of Arabidopsis sulfurtransferases.

Science.gov (United States)

Bauer, Michael; Dietrich, Christof; Nowak, Katharina; Sierralta, Walter D; Papenbrock, Jutta

2004-06-01

Sulfurtransferases (Str) comprise a group of enzymes widely distributed in archaea, eubacteria, and eukaryota which catalyze the transfer of a sulfur atom from suitable sulfur donors to nucleophilic sulfur acceptors. In all organisms analyzed to date, small gene families encoding Str proteins have been identified. The gene products were localized to different compartments of the cells. Our interest concerns the localization of Str proteins encoded in the nuclear genome of Arabidopsis. Computer-based prediction methods revealed localization in different compartments of the cell for six putative AtStrs. Several methods were used to determine the localization of the AtStr proteins experimentally. For AtStr1, a mitochondrial localization was demonstrated by immunodetection in the proteome of isolated mitochondria resolved by one- and two-dimensional gel electrophoresis and subsequent blotting. The respective mature AtStr1 protein was identified by mass spectrometry sequencing. The same result was obtained by transient expression of fusion constructs with the green fluorescent protein in Arabidopsis protoplasts, whereas AtStr2 was exclusively localized to the cytoplasm by this method. Three members of the single-domain AtStr were localized in the chloroplasts as demonstrated by transient expression of green fluorescent protein fusions in protoplasts and stomata, whereas the single-domain AtStr18 was shown to be cytoplasmic. The remarkable subcellular distribution of AtStr15 was additionally analyzed by transmission electron immunomicroscopy using a monospecific antibody against green fluorescent protein, indicating an attachment to the thylakoid membrane. The knowledge of the intracellular localization of the members of this multiprotein family will help elucidate their specific functions in the organism.

Genome-wide classification and expression analysis of MYB transcription factor families in rice and Arabidopsis

Science.gov (United States)

2012-01-01

Background The MYB gene family comprises one of the richest groups of transcription factors in plants. Plant MYB proteins are characterized by a highly conserved MYB DNA-binding domain. MYB proteins are classified into four major groups namely, 1R-MYB, 2R-MYB, 3R-MYB and 4R-MYB based on the number and position of MYB repeats. MYB transcription factors are involved in plant development, secondary metabolism, hormone signal transduction, disease resistance and abiotic stress tolerance. A comparative analysis of MYB family genes in rice and Arabidopsis will help reveal the evolution and function of MYB genes in plants. Results A genome-wide analysis identified at least 155 and 197 MYB genes in rice and Arabidopsis, respectively. Gene structure analysis revealed that MYB family genes possess relatively more number of introns in the middle as compared with C- and N-terminal regions of the predicted genes. Intronless MYB-genes are highly conserved both in rice and Arabidopsis. MYB genes encoding R2R3 repeat MYB proteins retained conserved gene structure with three exons and two introns, whereas genes encoding R1R2R3 repeat containing proteins consist of six exons and five introns. The splicing pattern is similar among R1R2R3 MYB genes in Arabidopsis. In contrast, variation in splicing pattern was observed among R1R2R3 MYB members of rice. Consensus motif analysis of 1kb upstream region (5′ to translation initiation codon) of MYB gene ORFs led to the identification of conserved and over-represented cis-motifs in both rice and Arabidopsis. Real-time quantitative RT-PCR analysis showed that several members of MYBs are up-regulated by various abiotic stresses both in rice and Arabidopsis. Conclusion A comprehensive genome-wide analysis of chromosomal distribution, tandem repeats and phylogenetic relationship of MYB family genes in rice and Arabidopsis suggested their evolution via duplication. Genome-wide comparative analysis of MYB genes and their expression analysis

Two differentially regulated Arabidopsis genes define a new branch of the DFR superfamily

DEFF Research Database (Denmark)

Østergaard, L; Lauvergeat, V; Naested, H

2001-01-01

that, whereas high expression of AtCRL1 in mature seeds declines during subsequent vegetative growth, transcriptional activity from the AtCRL2 promoter increases during vegetative growth. Expression of both genes is restricted to vascular tissue. Based upon their homology to proteins involved in lignin......Two tandem genes were identified on Arabidopsis chromosome II (AtCRL1 and AtCRL2) encoding proteins with homology to members of the dihydroflavonol-4-reductase (DFR) superfamily. The encoded CRL1 and CRL2 proteins share 87% mutual amino acid sequence identity whereas their promoter regions...

P-proteins in Arabidopsis are heteromeric structures involved in rapid sieve tube sealing.

Science.gov (United States)

Jekat, Stephan B; Ernst, Antonia M; von Bohl, Andreas; Zielonka, Sascia; Twyman, Richard M; Noll, Gundula A; Prüfer, Dirk

2013-01-01

Structural phloem proteins (P-proteins) are characteristic components of the sieve elements in all dicotyledonous and many monocotyledonous angiosperms. Tobacco P-proteins were recently confirmed to be encoded by the widespread sieve element occlusion (SEO) gene family, and tobacco SEO proteins were shown to be directly involved in sieve tube sealing thus preventing the loss of photosynthate. Analysis of the two Arabidopsis SEO proteins (AtSEOa and AtSEOb) indicated that the corresponding P-protein subunits do not act in a redundant manner. However, there are still pending questions regarding the interaction properties and specific functions of AtSEOa and AtSEOb as well as the general function of structural P-proteins in Arabidopsis. In this study, we characterized the Arabidopsis P-proteins in more detail. We used in planta bimolecular fluorescence complementation assays to confirm the predicted heteromeric interactions between AtSEOa and AtSEOb. Arabidopsis mutants depleted for one or both AtSEO proteins lacked the typical P-protein structures normally found in sieve elements, underlining the identity of AtSEO proteins as P-proteins and furthermore providing the means to determine the role of Arabidopsis P-proteins in sieve tube sealing. We therefore developed an assay based on phloem exudation. Mutants with reduced AtSEO expression levels lost twice as much photosynthate following injury as comparable wild-type plants, confirming that Arabidopsis P-proteins are indeed involved in sieve tube sealing.

P-proteins in Arabidopsis are heteromeric structures involved in rapid sieve tube sealing

Directory of Open Access Journals (Sweden)

Stephan B Jekat

2013-07-01

Full Text Available Structural phloem proteins (P-proteins are characteristic components of the sieve elements in all dicotyledonous and many monocotyledonous angiosperms. Tobacco P-proteins were recently evidenced to be encoded by the widespread SEO gene family, and tobacco SEO proteins were shown to be directly involved in sieve tube sealing thus preventing the loss of photosynthate. Analysis of the two Arabidopsis SEO proteins (AtSEOa and AtSEOb indicated that the corresponding P-protein subunits do not act in a redundant manner. However, there are still pending questions regarding the interaction properties and specific functions of AtSEOa and AtSEOb as well as the general function of structural P-proteins in Arabidopsis. In this study, we characterized the Arabidopsis P-proteins in more detail. We used in planta bimolecular fluorescence complementation assays to confirm the predicted heteromeric interactions between AtSEOa and AtSEOb. Arabidopsis mutants depleted for one or both AtSEO proteins lacked the typical P-protein structures normally found in sieve elements, underlining the identity of AtSEO proteins as P-proteins and furthermore providing the means to determine the role of Arabidopsis P-proteins in sieve tube sealing. We therefore developed an assay based on phloem exudation. Mutants with reduced AtSEO expression levels lost twice as much photosynthate following injury as comparable wild-type plants, confirming that Arabidopsis P-proteins are indeed involved in sieve tube sealing. 

Short-term exposure of Arabidopsis cell culures to hyper-G: Short-term changes in transcription regulation expression

Science.gov (United States)

Babbick, Maren; Hampp, Rudiger

2005-08-01

Callus cultures of Arabidopsis thaliana (cv. Columbia) were used to screen for early changes in gene expression in response to altered gravitational fields. In a recent microarray study we found hyper- g dependent changes in gene expression which indicated the involvement of WRKY genes [Martzivanou M. and Hampp R., Physiol. Plant., 118, 221-231,2003]. WRKY genes code for a family of plant-specific regulators of gene expression. In this study we report on the exposure of Arabidopsis callus cultures to 8g for up to 30 min. Quantitative analysis by real time RT-PCR of the amount of transcripts of WRKYs 3, 6, 22, 46, 65 and 70 showed individual changes in expression. As far as their function is known, these WRKY proteins are mainly involved in stress responses. As most alterations in transcript amount occurred within 10 min of treatment, such genes can be used for the investigation of microgravity-related effects on gene expression under sounding rocket conditions (TEXUS, MAXUS).

A Dehydration-Induced Eukaryotic Translation Initiation Factor iso4G Identified in a Slow Wilting Soybean Cultivar Enhances Abiotic Stress Tolerance in Arabidopsis

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Juan P. Gallino

2018-03-01

Full Text Available Water is usually the main limiting factor for soybean productivity worldwide and yet advances in genetic improvement for drought resistance in this crop are still limited. In the present study, we investigated the physiological and molecular responses to drought in two soybean contrasting genotypes, a slow wilting N7001 and a drought sensitive TJS2049 cultivars. Measurements of stomatal conductance, carbon isotope ratios and accumulated dry matter showed that N7001 responds to drought by employing mechanisms resulting in a more efficient water use than TJS2049. To provide an insight into the molecular mechanisms that these cultivars employ to deal with water stress, their early and late transcriptional responses to drought were analyzed by suppression subtractive hybridization. A number of differentially regulated genes from N7001 were identified and their expression pattern was compared between in this genotype and TJS2049. Overall, the data set indicated that N7001 responds to drought earlier than TJ2049 by up-regulating a larger number of genes, most of them encoding proteins with regulatory and signaling functions. The data supports the idea that at least some of the phenotypic differences between slow wilting and drought sensitive plants may rely on the regulation of the level and timing of expression of specific genes. One of the genes that exhibited a marked N7001-specific drought induction profile encoded a eukaryotic translation initiation factor iso4G (GmeIFiso4G-1a. GmeIFiso4G-1a is one of four members of this protein family in soybean, all of them sharing high sequence identity with each other. In silico analysis of GmeIFiso4G-1 promoter sequences suggested a possible functional specialization between distinct family members, which can attain differences at the transcriptional level. Conditional overexpression of GmeIFiso4G-1a in Arabidopsis conferred the transgenic plants increased tolerance to osmotic, salt, drought and low

Arabidopsis CDS blastp result: AK073288 [KOME

Lifescience Database Archive (English)

Full Text Available AK073288 J033028L24 At1g70550.2 expressed protein similar to hypothetical protein G...B:AAD31338 [Arabidopsis thaliana] and to putative putative carboxyl-terminal peptidase GB:AAC16072 [Arabidop

Arabidopsis CDS blastp result: AK242601 [KOME

Lifescience Database Archive (English)

Full Text Available AK242601 J090014G03 At3g03050.1 68416.m00301 cellulose synthase family protein (CslD3) similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose syntha

Arabidopsis CDS blastp result: AK110467 [KOME

Lifescience Database Archive (English)

Full Text Available AK110467 002-166-G08 At3g03050.1 cellulose synthase family protein (CslD3) similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-7 (gi:962

AHP2, AHP3, and AHP5 act downstream of CKI1 in Arabidopsis female gametophyte development.

Science.gov (United States)

Liu, Zhenning; Yuan, Li; Song, Xiaoya; Yu, Xiaolin; Sundaresan, Venkatesan

2017-06-15

Histidine phosphotransfer proteins (HPs) are key elements of the two-component signaling system, which act as a shuttle to transfer phosphorylation signals from histidine kinases (HKs) to response regulators (RRs). CYTOKININ INDEPENDENT 1 (CKI1), a key regulator of central cell specification in the Arabidopsis female gametophyte, activates the cytokinin signaling pathway through the Arabidopsis histidine phosphotransfer proteins (AHPs). There are five HP genes in Arabidopsis, AHP1-AHP5, but it remains unknown which AHP genes act downstream of CKI1 in Arabidopsis female gametophyte development. Promoter activity analysis of AHP1-AHP5 in embryo sacs revealed AHP1, AHP2, AHP3, and AHP5 expression in the central cell. Phenotypic studies of various combinations of ahp mutants showed that triple mutations in AHP2, AHP3, and AHP5 resulted in defective embryo sac development. Using cell-specific single and double markers in the female gametophyte, the ahp2-2 ahp3 ahp5-2/+ triple mutant ovules showed loss of central cell and antipodal cell fates and gain of egg cell or synergid cell attributes, resembling the cki1 mutant phenotypes. These data suggest that AHP2, AHP3, and AHP5 are the major factors acting downstream of CKI1 in the two-component cytokinin signaling pathway to promote Arabidopsis female gametophyte development. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

A potato NOA gene increased salinity tolerance in Arabidopsis ...

African Journals Online (AJOL)

ONOS

2010-09-06

Sep 6, 2010 ... in Arabidopsis thaliana salt stress responses and increased its salinity tolerance. Key words: StNOA1 ... (NR)-dependent pathways (Cueto et al., 1996; Delledonne ..... plastome-encoded proteins uncovers a mechanism for the.

Arabidopsis CDS blastp result: AK241860 [KOME

Lifescience Database Archive (English)

Full Text Available AK241860 J065216G12 At1g70550.1 68414.m08119 expressed protein similar to hypotheti...cal protein GB:AAD31338 [Arabidopsis thaliana] and to putative putative carboxyl-terminal peptidase GB:AAC16

Arabidopsis CDS blastp result: AK241860 [KOME

Lifescience Database Archive (English)

Full Text Available AK241860 J065216G12 At1g70550.2 68414.m08120 expressed protein similar to hypotheti...cal protein GB:AAD31338 [Arabidopsis thaliana] and to putative putative carboxyl-terminal peptidase GB:AAC16

Abscisic acid negatively regulates post-penetration resistance of Arabidopsis to the biotrophic powdery mildew fungus.

Science.gov (United States)

Xiao, Xiang; Cheng, Xi; Yin, Kangquan; Li, Huali; Qiu, Jin-Long

2017-08-01

Pytohormone abscisic acid (ABA) plays important roles in defense responses. Nonetheless, how ABA regulates plant resistance to biotrophic fungi remains largely unknown. Arabidopsis ABA-deficient mutants, aba2-1 and aba3-1, displayed enhanced resistance to the biotrophic powdery mildew fungus Golovinomyces cichoracearum. Moreover, exogenously administered ABA increased the susceptibility of Arabidopsis to G. cichoracearum. Arabidopsis ABA perception components mutants, abi1-1 and abi2-1, also displayed similar phenotypes to ABA-deficient mutants in resistance to G. cichoracearum. However, the resistance to G. cichoracearum is not changed in downstream ABA signaling transduction mutants, abi3-1, abi4-1, and abi5-1. Microscopic examination revealed that hyphal growth and conidiophore production of G. cichoracearum were compromised in the ABA deficient mutants, even though pre-penetration and penetration growth of the fungus were not affected. In addition, salicylic acid (SA) and MPK3 are found to be involved in ABA-regulated resistance to G. cichoracearum. Our work demonstrates that ABA negatively regulates post-penetration resistance of Arabidopsis to powdery mildew fungus G. cichoracearum, probably through antagonizing the function of SA.

The 1.7 Å resolution structure of At2g44920, a pentapeptide-repeat protein in the thylakoid lumen of Arabidopsis thaliana

International Nuclear Information System (INIS)

Ni, Shuisong; McGookey, Michael E.; Tinch, Stuart L.; Jones, Alisha N.; Jayaraman, Seetharaman; Tong, Liang; Kennedy, Michael A.

2011-01-01

The crystal structure of At2g44920, a pentapeptide repeat protein (PRP) from Arabidopsis thaliana, has been determined at 1.7 Å resolution. The structure represents the first PRP protein whose subcellular localization has been experimentally confirmed to be the thylakoid lumen of a plant species. At2g44920 belongs to a diverse family (Pfam PF00805) of pentapeptide-repeat proteins (PRPs) that are present in all known organisms except yeast. PRPs contain at least eight tandem-repeating sequences of five amino acids with an approximate consensus sequence (STAV)(D/N)(L/F)(S/T/R)(X). Recent crystal structures show that PRPs adopt a highly regular four-sided right-handed β-helical structure consisting mainly of type II and type IV β-turns, sometimes referred to as a repeated five-residue (or Rfr) fold. Among sequenced genomes, PRP genes are most abundant in cyanobacteria, leading to speculation that PRPs play an important role in the unique lifestyle of photosynthetic cyanobacteria. Despite the recent structural characterization of several cyanobacterial PRPs, most of their functions remain unknown. Plants, whose chloroplasts are of cyanobacterial origin, have only four PRP genes in their genomes. At2g44920 is one of three PRPs located in the thylakoid lumen. Here, the crystal structure of a double methionine mutant of residues 81–224 of At2g44920, the naturally processed fragment of one of its full-length isoforms, is reported at 1.7 Å resolution. The structure of At2g44920 consists of the characteristic Rfr fold with five uninterrupted coils made up of 25 pentapeptide repeats and α-helical elements capping both termini. A disulfide bridge links the two α-helices with a conserved loop between the helical elements at its C-terminus. This structure represents the first structure of a PRP protein whose subcellular location has been experimentally confirmed to be the thylakoid lumen in a plant species

Intracellular Localization of Arabidopsis Sulfurtransferases1

Science.gov (United States)

Bauer, Michael; Dietrich, Christof; Nowak, Katharina; Sierralta, Walter D.; Papenbrock, Jutta

2004-01-01

Sulfurtransferases (Str) comprise a group of enzymes widely distributed in archaea, eubacteria, and eukaryota which catalyze the transfer of a sulfur atom from suitable sulfur donors to nucleophilic sulfur acceptors. In all organisms analyzed to date, small gene families encoding Str proteins have been identified. The gene products were localized to different compartments of the cells. Our interest concerns the localization of Str proteins encoded in the nuclear genome of Arabidopsis. Computer-based prediction methods revealed localization in different compartments of the cell for six putative AtStrs. Several methods were used to determine the localization of the AtStr proteins experimentally. For AtStr1, a mitochondrial localization was demonstrated by immunodetection in the proteome of isolated mitochondria resolved by one- and two-dimensional gel electrophoresis and subsequent blotting. The respective mature AtStr1 protein was identified by mass spectrometry sequencing. The same result was obtained by transient expression of fusion constructs with the green fluorescent protein in Arabidopsis protoplasts, whereas AtStr2 was exclusively localized to the cytoplasm by this method. Three members of the single-domain AtStr were localized in the chloroplasts as demonstrated by transient expression of green fluorescent protein fusions in protoplasts and stomata, whereas the single-domain AtStr18 was shown to be cytoplasmic. The remarkable subcellular distribution of AtStr15 was additionally analyzed by transmission electron immunomicroscopy using a monospecific antibody against green fluorescent protein, indicating an attachment to the thylakoid membrane. The knowledge of the intracellular localization of the members of this multiprotein family will help elucidate their specific functions in the organism. PMID:15181206

Phytomelatonin receptor PMTR1-mediated signaling regulates stomatal closure in Arabidopsis thaliana.

Science.gov (United States)

Wei, Jian; Li, Dong-Xu; Zhang, Jia-Rong; Shan, Chi; Rengel, Zed; Song, Zhong-Bang; Chen, Qi

2018-04-27

Melatonin has been detected in plants in 1995; however, the function and signaling pathway of this putative phytohormone are largely undetermined due to a lack of knowledge about its receptor. Here, we discovered the first phytomelatonin receptor (CAND2/PMTR1) in Arabidopsis thaliana and found that melatonin governs the receptor-dependent stomatal closure. The application of melatonin induced stomatal closure through the heterotrimeric G protein α subunit-regulated H 2 O 2 and Ca 2+ signals. The Arabidopsis mutant lines lacking AtCand2 that encodes a candidate G protein-coupled receptor were insensitive to melatonin-induced stomatal closure. Accordingly, the melatonin-induced H 2 O 2 production and Ca 2+ influx were completely abolished in cand2. CAND2 is a membrane protein that interacts with GPA1 and the expression of AtCand2 was tightly regulated by melatonin in various organs and guard cells. CAND2 showed saturable and specific 125 I-melatonin binding, with apparent K d (dissociation constant) of 0.73 ± 0.10 nmol/L (r 2  = .99), demonstrating this protein is a phytomelatonin receptor (PMTR1). Our results suggest that the phytomelatonin regulation of stomatal closure is dependent on its receptor CAND2/PMTR1-mediated H 2 O 2 and Ca 2+ signaling transduction cascade. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Induction of Oxidative Stress and Antioxidative Mechanisms in Arabidopsis thaliana after Uranium Exposure at pH 7.5

Directory of Open Access Journals (Sweden)

Eline Saenen

2015-06-01

Full Text Available To evaluate the environmental impact of uranium (U contamination, it is important to investigate the effects of U at ecologically relevant conditions. Since U speciation, and hence its toxicity, strongly depends on environmental pH, the present study aimed to investigate dose-dependent effects of U at pH 7.5. Arabidopsis thaliana plants (Mouse-ear Cress were exposed for three days to different U concentrations at pH 7.5. In the roots, the increased capacities of ascorbate peroxidase and glutathione reductase indicate an important role for the ascorbate-glutathione cycle during U-induced stress. However, a significant decrease in the ascorbate redox state was observed after exposure to 75 and 100 µM U, indicating that those roots are severely stressed. In accordance with the roots, the ascorbate-glutathione cycle plays an important role in the antioxidative defence systems in A. thaliana leaves exposed to U at pH 7.5 as the ascorbate and glutathione biosynthesis were upregulated. In addition, small inductions of enzymes of the antioxidative defence system were observed at lower U concentrations to counteract the U-induced stress. However, at higher U concentrations it seems that the antioxidative defence system of the leaves collapses as reductions in enzyme activities and gene expression levels were observed.

Survey of the rubber tree genome reveals a high number of cysteine protease-encoding genes homologous to Arabidopsis SAG12.

Science.gov (United States)

Zou, Zhi; Liu, Jianting; Yang, Lifu; Xie, Guishui

2017-01-01

Arabidopsis thaliana SAG12, a senescence-specific gene encoding a cysteine protease, is widely used as a molecular marker for the study of leaf senescence. To date, its potential orthologues have been isolated from several plant species such as Brassica napus and Nicotiana tabacum. However, little information is available in rubber tree (Hevea brasiliensis), a rubber-producing plant of the Euphorbiaceae family. This study presents the identification of SAG12-like genes from the rubber tree genome. Results showed that an unexpected high number of 17 rubber orthologues with a single intron were found, contrasting the single copy with two introns in Arabidopsis. The gene expansion was also observed in another two Euphorbiaceae plants, castor bean (Ricinus communis) and physic nut (Jatropha curcas), both of which contain 8 orthologues. In accordance with no occurrence of recent whole-genome duplication (WGD) events, most duplicates in castor and physic nut were resulted from tandem duplications. In contrast, the duplicated HbSAG12H genes were derived from tandem duplications as well as the recent WGD. Expression analysis showed that most HbSAG12H genes were lowly expressed in examined tissues except for root and male flower. Furthermore, HbSAG12H1 exhibits a strictly senescence-associated expression pattern in rubber tree leaves, and thus can be used as a marker gene for the study of senescence mechanism in Hevea.

Arabidopsis CDS blastp result: AK242601 [KOME

Lifescience Database Archive (English)

Full Text Available AK242601 J090014G03 At1g32180.1 68414.m03958 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-9 (gi:9622890) from Zea mays 0.0 ...

Co-overexpressing a Plasma Membrane and a Vacuolar Membrane Sodium/Proton Antiporter Significantly Improves Salt Tolerance in Transgenic Arabidopsis Plants

Science.gov (United States)

Pehlivan, Necla; Sun, Li; Jarrett, Philip; Yang, Xiaojie; Mishra, Neelam; Chen, Lin; Kadioglu, Asim; Shen, Guoxin; Zhang, Hong

2016-01-01

The Arabidopsis gene AtNHX1 encodes a vacuolar membrane-bound sodium/proton (Na+/H+) antiporter that transports Na+ into the vacuole and exports H+ into the cytoplasm. The Arabidopsis gene SOS1 encodes a plasma membrane-bound Na+/H+ antiporter that exports Na+ to the extracellular space and imports H+ into the plant cell. Plants rely on these enzymes either to keep Na+ out of the cell or to sequester Na+ into vacuoles to avoid the toxic level of Na+ in the cytoplasm. Overexpression of AtNHX1 or SOS1 could improve salt tolerance in transgenic plants, but the improved salt tolerance is limited. NaCl at concentration >200 mM would kill AtNHX1-overexpressing or SOS1-overexpressing plants. Here it is shown that co-overexpressing AtNHX1 and SOS1 could further improve salt tolerance in transgenic Arabidopsis plants, making transgenic Arabidopsis able to tolerate up to 250 mM NaCl treatment. Furthermore, co-overexpression of AtNHX1 and SOS1 could significantly reduce yield loss caused by the combined stresses of heat and salt, confirming the hypothesis that stacked overexpression of two genes could substantially improve tolerance against multiple stresses. This research serves as a proof of concept for improving salt tolerance in other plants including crops. PMID:26985021

Arabidopsis CDS blastp result: AK071899 [KOME

Lifescience Database Archive (English)

Full Text Available AK071899 J013059G06 At1g44446.1 chlorophyll a oxygenase (CAO) / chlorophyll b synthase identical to chloroph...yll a oxygenase GI:5853117 from [Arabidopsis thaliana]; contains Pfam PF00355 Rieske [2Fe-2S] domain 1e-154 ...

ADN ribosomique 5S chez Arabidopsis thaliana : dynamique chromatinienne et ARN polymérase IV

OpenAIRE

Douet , Julien

2008-01-01

In Arabidopsis thaliana, 5S rRNA genes are found clustered at pericentromeric heterochromatin of chromosomes 3, 4 and 5. 5S rRNA genes transcription is epigenetically regulated through the formation of specific chromatin structure. In order to determine the events that lead to the establishment of such structures, a study during the first steps of post-germinative plant development was done. Unexpectedly, we observed a decondensation followed by a rapid "re"condensation of 5S rDNA chromatin. ...

Identification of proteins interacting with Arabidopsis ACD11

DEFF Research Database (Denmark)

Petersen, Nikolaj H T; Joensen, Jan; McKinney, Lea V

2009-01-01

The Arabidopsis ACD11 gene encodes a sphingosine transfer protein and was identified by the accelerated cell death phenotype of the loss of function acd11 mutant, which exhibits heightened expression of genes involved in the disease resistance hypersensitive response (HR). We used ACD11 as bait...... in a yeast two-hybrid screen of an Arabidopsis cDNA library to identify ACD11 interacting proteins. One interactor identified is a protein of unknown function with an RNA recognition motif (RRM) designated BPA1 (binding partner of ACD11). Co-immunoprecipitation experiments confirmed the ACD11-BPA1...

The ANGULATA7 gene encodes a DnaJ-like zinc finger-domain protein involved in chloroplast function and leaf development in Arabidopsis.

Science.gov (United States)

Muñoz-Nortes, Tamara; Pérez-Pérez, José Manuel; Ponce, María Rosa; Candela, Héctor; Micol, José Luis

2017-03-01

The characterization of mutants with altered leaf shape and pigmentation has previously allowed the identification of nuclear genes that encode plastid-localized proteins that perform essential functions in leaf growth and development. A large-scale screen previously allowed us to isolate ethyl methanesulfonate-induced mutants with small rosettes and pale green leaves with prominent marginal teeth, which were assigned to a phenotypic class that we dubbed Angulata. The molecular characterization of the 12 genes assigned to this phenotypic class should help us to advance our understanding of the still poorly understood relationship between chloroplast biogenesis and leaf morphogenesis. In this article, we report the phenotypic and molecular characterization of the angulata7-1 (anu7-1) mutant of Arabidopsis thaliana, which we found to be a hypomorphic allele of the EMB2737 gene, which was previously known only for its embryonic-lethal mutations. ANU7 encodes a plant-specific protein that contains a domain similar to the central cysteine-rich domain of DnaJ proteins. The observed genetic interaction of anu7-1 with a loss-of-function allele of GENOMES UNCOUPLED1 suggests that the anu7-1 mutation triggers a retrograde signal that leads to changes in the expression of many genes that normally function in the chloroplasts. Many such genes are expressed at higher levels in anu7-1 rosettes, with a significant overrepresentation of those required for the expression of plastid genome genes. Like in other mutants with altered expression of plastid-encoded genes, we found that anu7-1 exhibits defects in the arrangement of thylakoidal membranes, which appear locally unappressed. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

Arabidopsis CDS blastp result: AK105724 [KOME

Lifescience Database Archive (English)

Full Text Available AK105724 001-201-G07 At1g07110.1 fructose-6-phosphate 2-kinase / fructose-2,6-bisph...osphatase (F2KP) identical to fructose-6-phosphate 2-kinase/fructose-2,6-bisphosphatase (F2KP) [Arabidopsis thaliana] GI:13096098 0.0 ...

Arabidopsis AtDjA3 null mutant shows increased sensitivity to abscisic acid, salt, and osmotic stress in germination and postgermination stages

Directory of Open Access Journals (Sweden)

Silvia eSalas-Muñoz

2016-02-01

Full Text Available DnaJ proteins are essential co-chaperones involved in abiotic and biotic stress responses. Arabidopsis AtDjA3 gene encodes a molecular co-chaperone of 420 amino acids, which belongs to the J-protein family. In this study, we report the functional characterization of the AtDjA3 gene using the Arabidopsis knockout line designated j3 and the 35S::AtDjA3 overexpression lines. Loss of AtDjA3 function was associated with small seed production. In fact, j3 mutant seeds showed a reduction of 24% in seed weight compared to Col-0 seeds. Expression analysis showed that the AtDjA3 gene was modulated in response to NaCl, glucose, and abscisic acid. The j3 line had increased sensitivity to NaCl and glucose treatments in the germination and cotyledon development in comparison to parental Col-0. Furthermore, the j3 mutant line exhibited higher abscisic acid sensitivity in comparison to parental Col-0 and 35S::AtDjA3 overexpression lines. In addition, we examined the expression of ABI3 gene, which is a central regulator in ABA signalling, in j3 mutant and 35S::AtDjA3 overexpression lines. Under 5 μM ABA treatment at 24 h, j3 mutant seedlings displayed higher ABI3 expression, whereas in 35S::AtDjA3 overexpression lines, ABI3 gene expression was repressed. Taken together, these results demonstrate that the AtDjA3 gene is involved in seed development and abiotic stress tolerance.

Photorepair mutants of Arabidopsis

International Nuclear Information System (INIS)

Jiang, C.Z.; Yee, J.; Mitchell, D.L.; Britt, A.B.

1997-01-01

UV radiation induces two major DNA damage products, the cyclobutane pyrimidine dimer (CPD) and, at a lower frequency, the pyrimidine (6-4) pyrimidinone dimer (6-4 product). Although Escherichia coli and Saccharomyces cerevisiae produce a CPD-specific photolyase that eliminates only this class of dimer, Arabidopsis thaliana, Drosophila melanogaster, Crotalus atrox, and Xenopus laevis have recently been shown to photoreactivate both CPDs and 6-4 products. We describe the isolation and characterization of two new classes of mutants of Arabidopsis, termed uvr2 and uvr3, that are defective in the photoreactivation of CPDs and 6-4 products, respectively. We demonstrate that the CPD photolyase mutation is genetically linked to a DNA sequence encoding a type II (metazoan) CPD photolyase. In addition, we are able to generate plants in which only CPDs or 6-4 products are photoreactivated in the nuclear genome by exposing these mutants to UV light and then allowing them to repair one or the other class of dimers. This provides us with a unique opportunity to study the biological consequences of each of these two major UV-induced photoproducts in an intact living system

Small RNAs and the regulation of cis-natural antisense transcripts in Arabidopsis

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Lonardi Stefano

2008-01-01

Full Text Available Abstract Background In spite of large intergenic spaces in plant and animal genomes, 7% to 30% of genes in the genomes encode overlapping cis-natural antisense transcripts (cis-NATs. The widespread occurrence of cis-NATs suggests an evolutionary advantage for this type of genomic arrangement. Experimental evidence for the regulation of two cis-NAT gene pairs by natural antisense transcripts-generated small interfering RNAs (nat-siRNAs via the RNA interference (RNAi pathway has been reported in Arabidopsis. However, the extent of siRNA-mediated regulation of cis-NAT genes is still unclear in any genome. Results The hallmarks of RNAi regulation of NATs are 1 inverse regulation of two genes in a cis-NAT pair by environmental and developmental cues and 2 generation of siRNAs by cis-NAT genes. We examined Arabidopsis transcript profiling data from public microarray databases to identify cis-NAT pairs whose sense and antisense transcripts show opposite expression changes. A subset of the cis-NAT genes displayed negatively correlated expression profiles as well as inverse differential expression changes under at least one of the examined developmental stages or treatment conditions. By searching the Arabidopsis Small RNA Project (ASRP and Massively Parallel Signature Sequencing (MPSS small RNA databases as well as our stress-treated small RNA dataset, we found small RNAs that matched at least one gene in 646 pairs out of 1008 (64% protein-coding cis-NAT pairs, which suggests that siRNAs may regulate the expression of many cis-NAT genes. 209 putative siRNAs have the potential to target more than one gene and half of these small RNAs could target multiple members of a gene family. Furthermore, the majority of the putative siRNAs within the overlapping regions tend to target only one transcript of a given NAT pair, which is consistent with our previous finding on salt- and bacteria-induced nat-siRNAs. In addition, we found that genes encoding plastid- or

Highly sensitive electrochemical immunoassay for human IgG using double-encoded magnetic redox-active nanoparticles

International Nuclear Information System (INIS)

Tang, D.; Tang, J.; Su, B.; Chen, H.; Chen, G.; Huang, J.

2010-01-01

A new sandwich-type electrochemical immunoassay was developed for the detection of human IgG using doubly-encoded and magnetic redox-active nanoparticles as recognition elements on the surface of a glassy carbon electrode modified with anti-IgG on nanogold particles. The recognition elements were synthesized by coating magnetic Fe3O4 nanoparticles with Prussian blue nanoparticles and then covered with peroxidase-labeled anti-IgG antibodies (POx-anti-IgG) on Prussian blue nanoparticles. The immunoelectrode displays very good electrochemical properties towards detection of IgG via using double-encoded magnetic redox-active nanoparticles as trace and hydrogen peroxide as enzyme substrate. Its limit of detection (10 pmol.L -1 ) is 10-fold better than that of using plain POx-anti-IgG secondary antibodies. The method was applied to the detection of IgG in serum samples, and an excellent correspondence with the reference values was found. (author)

A non-canonical transferred DNA insertion at the BRI1 locus in Arabidopsis thaliana.

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Zhao, Zhong; Zhu, Yan; Erhardt, Mathieu; Ruan, Ying; Shen, Wen-Hui

2009-04-01

Agrobacterium-mediated transformation is widely used in transgenic plant engineering and has been proven to be a powerful tool for insertional mutagenesis of the plant genome. The transferred DNA (T-DNA) from Agrobacterium is integrated into the plant genome through illegitimate recombination between the T-DNA and the plant DNA. Contrasting to the canonical insertion, here we report on a locus showing a complex mutation associated with T-DNA insertion at the BRI1 gene in Arabidopsis thaliana. We obtained a mutant line, named salade for its phenotype of dwarf stature and proliferating rosette. Molecular characterization of this mutant revealed that in addition to T-DNA a non-T-DNA-localized transposon from bacteria was inserted in the Arabidopsis genome and that a region of more than 11.5 kb of the Arabidopsis genome was deleted at the insertion site. The deleted region contains the brassinosteroid receptor gene BRI1 and the transcription factor gene WRKY13. Our finding reveals non-canonical T-DNA insertion, implicating horizontal gene transfer and cautioning the use of T-DNA as mutagen in transgenic research.

Expression, purification, crystallization and preliminary X-ray diffraction analysis of Arabidopsis thaliana cyclophilin 38 (AtCyp38)

International Nuclear Information System (INIS)

Vasudevan, Dileep; Gopalan, Gayathri; He, Zengyong; Luan, Sheng; Swaminathan, Kunchithapadam

2005-01-01

Crystallization of Arabidopsis thaliana cyclophilin 38. The crystal diffracts X-rays to 2.5 Å resolution. AtCyp38 is one of the highly divergent multidomain cyclophilins from Arabidopsis thaliana. A recombinant form of AtCyp38 (residues 83–437) was expressed in Escherichia coli and purified to homogeneity. The protein was crystallized using the vapour-batch technique with PEG 6000 and t-butanol as precipitants. Crystals of recombinant AtCyp38 diffracted X-rays to better than 2.5 Å resolution at 95 K using a synchrotron-radiation source. The crystal belongs to the C-centred orthorhombic space group C222 1 , with unit-cell parameters a = 58.2, b = 95.9, c = 167.5 Å, and contains one molecule in the asymmetric unit. The selenomethionine derivative of the AtCyp38 protein was overexpressed, purified and crystallized in the same space group and data were collected to 3.5 Å at the NSLS synchrotron. The structure is being solved by the MAD method

Two Chimeric Regulators of G-protein Signaling (RGS) Proteins Differentially Modulate Soybean Heterotrimeric G-protein Cycle*

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Roy Choudhury, Swarup; Westfall, Corey S.; Laborde, John P.; Bisht, Naveen C.; Jez, Joseph M.; Pandey, Sona

2012-01-01

Heterotrimeric G-proteins and the regulator of G-protein signaling (RGS) proteins, which accelerate the inherent GTPase activity of Gα proteins, are common in animals and encoded by large gene families; however, in plants G-protein signaling is thought to be more limited in scope. For example, Arabidopsis thaliana contains one Gα, one Gβ, three Gγ, and one RGS protein. Recent examination of the Glycine max (soybean) genome reveals a larger set of G-protein-related genes and raises the possibility of more intricate G-protein networks than previously observed in plants. Stopped-flow analysis of GTP-binding and GDP/GTP exchange for the four soybean Gα proteins (GmGα1–4) reveals differences in their kinetic properties. The soybean genome encodes two chimeric RGS proteins with an N-terminal seven transmembrane domain and a C-terminal RGS box. Both GmRGS interact with each of the four GmGα and regulate their GTPase activity. The GTPase-accelerating activities of GmRGS1 and -2 differ for each GmGα, suggesting more than one possible rate of the G-protein cycle initiated by each of the Gα proteins. The differential effects of GmRGS1 and GmRGS2 on GmGα1–4 result from a single valine versus alanine difference. The emerging picture suggests complex regulation of the G-protein cycle in soybean and in other plants with expanded G-protein networks. PMID:22474294

XAP5 CIRCADIAN TIMEKEEPER Positively Regulates RESISTANCE TO POWDERY MILDEW8.1–Mediated Immunity in Arabidopsis

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Yong-Ju Xu

2017-11-01

Full Text Available Ectopic expression of the Arabidopsis RESISTANCE TO POWDERY MILDEW8.1 (RPW8.1 boosts pattern-triggered immunity leading to enhanced resistance to different pathogens in Arabidopsis and rice. However, the underlying regulatory mechanism remains largely elusive. Here, we report that XAP5 CIRCADIAN TIMEKEEPER (XCT, At2g21150 positively regulates RPW8.1-mediated cell death and disease resistance. Forward genetic screen identified the b3-17 mutant that exhibited less cell death and susceptibility to powdery mildew and bacterial pathogens. Map-based cloning identified a G-to-A point mutation at the 3′ splice site of the 8th intron, which resulted in splice shift to 8-bp down-stream of the original splice site of XCT in b3-17, and introduced into a stop codon after two codons leading to a truncated XCT. XCT has previously been identified as a circadian clock gene required for small RNA biogenesis and acting down-stream of ETHYLENE-INSENSITIVE3 (EIN3 in the ethylene-signaling pathway. Here we further showed that mutation or down-regulation of XCT by artificial microRNA reduced RPW8.1-mediated immunity in R1Y4, a transgenic line expressing RPW8.1-YFP from the RPW8.1 native promoter. On the contrary, overexpression of XCT in R1Y4 background enhanced RPW8.1-mediated cell death, H2O2 production and resistance against powdery mildew. Consistently, the expression of RPW8.1 was down- and up-regulated in xct mutant and XCT overexpression lines, respectively. Taken together, these results indicate that XCT positively regulates RPW8.1-mediated cell death and disease resistance, and provide new insight into the regulatory mechanism of RPW8.1-mediated immunity.

Expression of cinnamyl alcohol dehydrogenases and their putative homologues during Arabidopsis thaliana growth and development: lessons for database annotations?

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Kim, Sung-Jin; Kim, Kye-Won; Cho, Man-Ho; Franceschi, Vincent R; Davin, Laurence B; Lewis, Norman G

2007-07-01

A major goal currently in Arabidopsis research is determination of the (biochemical) function of each of its approximately 27,000 genes. To date, however, 12% of its genes actually have known biochemical roles. In this study, we considered it instructive to identify the gene expression patterns of nine (so-called AtCAD1-9) of 17 genes originally annotated by The Arabidopsis Information Resource (TAIR) as cinnamyl alcohol dehydrogenase (CAD, EC 1.1.1.195) homologues [see Costa, M.A., Collins, R.E., Anterola, A.M., Cochrane, F.C., Davin, L.B., Lewis N.G., 2003. An in silico assessment of gene function and organization of the phenylpropanoid pathway metabolic networks in Arabidopsis thaliana and limitations thereof. Phytochemistry 64, 1097-1112.]. In agreement with our biochemical studies in vitro [Kim, S.-J., Kim, M.-R., Bedgar, D.L., Moinuddin, S.G.A., Cardenas, C.L., Davin, L.B., Kang, C.-H., Lewis, N.G., 2004. Functional reclassification of the putative cinnamyl alcohol dehydrogenase multigene family in Arabidopsis. Proc. Natl. Acad. Sci. USA 101, 1455-1460.], and analysis of a double mutant [Sibout, R., Eudes, A., Mouille, G., Pollet, B., Lapierre, C., Jouanin, L., Séguin A., 2005. Cinnamyl Alcohol Dehydrogenase-C and -D are the primary genes involved in lignin biosynthesis in the floral stem of Arabidopsis. Plant Cell 17, 2059-2076.], both AtCAD5 (At4g34230) and AtCAD4 (At3g19450) were found to have expression patterns consistent with development/formation of different forms of the lignified vascular apparatus, e.g. lignifying stem tissues, bases of trichomes, hydathodes, abscission zones of siliques, etc. Expression was also observed in various non-lignifying zones (e.g. root caps) indicative of, perhaps, a role in plant defense. In addition, expression patterns of the four CAD-like homologues were investigated, i.e. AtCAD2 (At2g21730), AtCAD3 (At2g21890), AtCAD7 (At4g37980) and AtCAD8 (At4g37990), each of which previously had been demonstrated to have low CAD

Co-overexpressing a Plasma Membrane and a Vacuolar Membrane Sodium/Proton Antiporter Significantly Improves Salt Tolerance in Transgenic Arabidopsis Plants.

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Pehlivan, Necla; Sun, Li; Jarrett, Philip; Yang, Xiaojie; Mishra, Neelam; Chen, Lin; Kadioglu, Asim; Shen, Guoxin; Zhang, Hong

2016-05-01

The Arabidopsis gene AtNHX1 encodes a vacuolar membrane-bound sodium/proton (Na(+)/H(+)) antiporter that transports Na(+) into the vacuole and exports H(+) into the cytoplasm. The Arabidopsis gene SOS1 encodes a plasma membrane-bound Na(+)/H(+) antiporter that exports Na(+) to the extracellular space and imports H(+) into the plant cell. Plants rely on these enzymes either to keep Na(+) out of the cell or to sequester Na(+) into vacuoles to avoid the toxic level of Na(+) in the cytoplasm. Overexpression of AtNHX1 or SOS1 could improve salt tolerance in transgenic plants, but the improved salt tolerance is limited. NaCl at concentration >200 mM would kill AtNHX1-overexpressing or SOS1-overexpressing plants. Here it is shown that co-overexpressing AtNHX1 and SOS1 could further improve salt tolerance in transgenic Arabidopsis plants, making transgenic Arabidopsis able to tolerate up to 250 mM NaCl treatment. Furthermore, co-overexpression of AtNHX1 and SOS1 could significantly reduce yield loss caused by the combined stresses of heat and salt, confirming the hypothesis that stacked overexpression of two genes could substantially improve tolerance against multiple stresses. This research serves as a proof of concept for improving salt tolerance in other plants including crops. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.

Arabidopsis CDS blastp result: AK106306 [KOME

Lifescience Database Archive (English)

Full Text Available AK106306 002-101-C10 At4g37750.1 ovule development protein aintegumenta (ANT) ident...ical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 3e-89 ...

Synthesis of hydroxylated sterols in transgenic Arabidopsis plants alters growth and steroid metabolism.

Science.gov (United States)

Beste, Lisa; Nahar, Nurun; Dalman, Kerstin; Fujioka, Shozo; Jonsson, Lisbeth; Dutta, Paresh C; Sitbon, Folke

2011-09-01

To explore mechanisms in plant sterol homeostasis, we have here increased the turnover of sterols in Arabidopsis (Arabidopsis thaliana) and potato (Solanum tuberosum) plants by overexpressing four mouse cDNA encoding cholesterol hydroxylases (CHs), hydroxylating cholesterol at the C-7, C-24, C-25, or C-27 positions. Compared to the wild type, the four types of Arabidopsis transformant showed varying degrees of phenotypic alteration, the strongest one being in CH25 lines, which were dark-green dwarfs resembling brassinosteroid-related mutants. Gas chromatography-mass spectrometry analysis of extracts from wild-type Arabidopsis plants revealed trace levels of α and β forms of 7-hydroxycholesterol, 7-hydroxycampesterol, and 7-hydroxysitosterol. The expected hydroxycholesterol metabolites in CH7-, CH24-, and CH25 transformants were identified and quantified using gas chromatography-mass spectrometry. Additional hydroxysterol forms were also observed, particularly in CH25 plants. In CH24 and CH25 lines, but not in CH7 ones, the presence of hydroxysterols was correlated with a considerable alteration of the sterol profile and an increased sterol methyltransferase activity in microsomes. Moreover, CH25 lines contained clearly reduced levels of brassinosteroids, and displayed an enhanced drought tolerance. Equivalent transformations of potato plants with the CH25 construct increased hydroxysterol levels, but without the concomitant alteration of growth and sterol profiles observed in Arabidopsis. The results suggest that an increased hydroxylation of cholesterol and/or other sterols in Arabidopsis triggers compensatory processes, acting to maintain sterols at adequate levels.

LSM Proteins Provide Accurate Splicing and Decay of Selected Transcripts to Ensure Normal Arabidopsis Development[W

Science.gov (United States)

Perea-Resa, Carlos; Hernández-Verdeja, Tamara; López-Cobollo, Rosa; Castellano, María del Mar; Salinas, Julio

2012-01-01

In yeast and animals, SM-like (LSM) proteins typically exist as heptameric complexes and are involved in different aspects of RNA metabolism. Eight LSM proteins, LSM1 to 8, are highly conserved and form two distinct heteroheptameric complexes, LSM1-7 and LSM2-8,that function in mRNA decay and splicing, respectively. A search of the Arabidopsis thaliana genome identifies 11 genes encoding proteins related to the eight conserved LSMs, the genes encoding the putative LSM1, LSM3, and LSM6 proteins being duplicated. Here, we report the molecular and functional characterization of the Arabidopsis LSM gene family. Our results show that the 11 LSM genes are active and encode proteins that are also organized in two different heptameric complexes. The LSM1-7 complex is cytoplasmic and is involved in P-body formation and mRNA decay by promoting decapping. The LSM2-8 complex is nuclear and is required for precursor mRNA splicing through U6 small nuclear RNA stabilization. More importantly, our results also reveal that these complexes are essential for the correct turnover and splicing of selected development-related mRNAs and for the normal development of Arabidopsis. We propose that LSMs play a critical role in Arabidopsis development by ensuring the appropriate development-related gene expression through the regulation of mRNA splicing and decay. PMID:23221597

Genome interrogation for novel salinity tolerant Arabidopsis mutants.

Science.gov (United States)

van Tol, Niels; Pinas, Johan; Schat, Henk; Hooykaas, Paul J J; van der Zaal, Bert J

2016-12-01

Soil salinity is becoming an increasingly large problem in agriculture. In this study, we have investigated whether a capacity to withstand salinity can be induced in the salinity sensitive plant species Arabidopsis thaliana, and whether it can be maintained in subsequent generations. To this end, we have used zinc finger artificial transcription factor (ZF-ATFs) mediated genome interrogation. Already within a relatively small collection Arabidopsis lines expressing ZF-ATFs, we found 41 lines that were tolerant to 100 mM NaCl. Furthermore, ZF-ATF encoding gene constructs rescued from the most strongly salinity tolerant lines were indeed found to act as dominant and heritable agents for salinity tolerance. Altogether, our data provide evidence that a silent capacity to withstand normally lethal levels of salinity exists in Arabidopsis and can be evoked relatively easily by in trans acting transcription factors like ZF-ATFs. © 2016 John Wiley & Sons Ltd.

Arabidopsis CDS blastp result: AK104980 [KOME

Lifescience Database Archive (English)

Full Text Available AK104980 001-125-D09 At1g70550.2 expressed protein similar to hypothetical protein ...GB:AAD31338 [Arabidopsis thaliana] and to putative putative carboxyl-terminal peptidase GB:AAC16072 [Arabido

Arabidopsis CDS blastp result: AK287673 [KOME

Lifescience Database Archive (English)

Full Text Available AK287673 J065121E18 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 6e-17 ...

Arabidopsis CDS blastp result: AK241272 [KOME

Lifescience Database Archive (English)

Full Text Available AK241272 J065132I19 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 1e-88 ...

Arabidopsis CDS blastp result: AK241712 [KOME

Lifescience Database Archive (English)

Full Text Available AK241712 J065197H24 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 6e-27 ...

Arabidopsis CDS blastp result: AK287726 [KOME

Lifescience Database Archive (English)

Full Text Available AK287726 J065138E17 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 1e-88 ...

Arabidopsis CDS blastp result: AK242387 [KOME

Lifescience Database Archive (English)

Full Text Available AK242387 J080051E14 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 2e-45 ...

Arabidopsis CDS blastp result: AK242957 [KOME

Lifescience Database Archive (English)

Full Text Available AK242957 J090089I15 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 1e-28 ...

The plastid casein kinase 2 phosphorylates Rubisco activase at the Thr-78 site but is not essential for regulation of Rubisco activation state

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Rubisco activase (RCA) is essential for the activation of Rubisco, the carboxylating enzyme of photosynthesis. In Arabidopsis, RCA is encoded by a single gene (At2g39730) that is alternatively spliced to form a large alpha-RCA and small beta-RCA isoform. The activity of Rubisco is controlled in res...

Arabidopsis Glutamate Receptor Homolog3.5 Modulates Cytosolic Ca2+ Level to Counteract Effect of Abscisic Acid in Seed Germination1[OPEN

Science.gov (United States)

Kong, Dongdong; Ju, Chuanli; Parihar, Aisha; Kim, So; Cho, Daeshik; Kwak, June M.

2015-01-01

Seed germination is a critical step in a plant’s life cycle that allows successful propagation and is therefore strictly controlled by endogenous and environmental signals. However, the molecular mechanisms underlying germination control remain elusive. Here, we report that the Arabidopsis (Arabidopsis thaliana) glutamate receptor homolog3.5 (AtGLR3.5) is predominantly expressed in germinating seeds and increases cytosolic Ca2+ concentration that counteracts the effect of abscisic acid (ABA) to promote germination. Repression of AtGLR3.5 impairs cytosolic Ca2+ concentration elevation, significantly delays germination, and enhances ABA sensitivity in seeds, whereas overexpression of AtGLR3.5 results in earlier germination and reduced seed sensitivity to ABA. Furthermore, we show that Ca2+ suppresses the expression of ABSCISIC ACID INSENSITIVE4 (ABI4), a key transcription factor involved in ABA response in seeds, and that ABI4 plays a fundamental role in modulation of Ca2+-dependent germination. Taken together, our results provide molecular genetic evidence that AtGLR3.5-mediated Ca2+ influx stimulates seed germination by antagonizing the inhibitory effects of ABA through suppression of ABI4. These findings establish, to our knowledge, a new and pivotal role of the plant glutamate receptor homolog and Ca2+ signaling in germination control and uncover the orchestrated modulation of the AtGLR3.5-mediated Ca2+ signal and ABA signaling via ABI4 to fine-tune the crucial developmental process, germination, in Arabidopsis. PMID:25681329

Arabidopsis CDS blastp result: AK242585 [KOME

Lifescience Database Archive (English)

Full Text Available AK242585 J090010M20 At3g03050.1 68416.m00301 cellulose synthase family protein (CslD3) similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose syntha

Arabidopsis CDS blastp result: AK242890 [KOME

Lifescience Database Archive (English)

Full Text Available AK242890 J090079L19 At3g03050.1 68416.m00301 cellulose synthase family protein (CslD3) similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose syntha

Structural Redesigning Arabidopsis Lignins into Alkali-Soluble Lignins through the Expression of p-Coumaroyl-CoA:Monolignol Transferase PMT1

Science.gov (United States)

Sibout, Richard; Le Bris, Philippe; Cézard, Laurent

2016-01-01

Grass lignins can contain up to 10% to 15% by weight of p-coumaric esters. This acylation is performed on monolignols under the catalysis of p-coumaroyl-coenzyme A monolignol transferase (PMT). To study the impact of p-coumaroylation on lignification, we first introduced the Brachypodium distachyon Bradi2g36910 (BdPMT1) gene into Arabidopsis (Arabidopsis thaliana) under the control of the constitutive maize (Zea mays) ubiquitin promoter. The resulting p-coumaroylation was far lower than that of lignins from mature grass stems and had no impact on stem lignin content. By contrast, introducing either the BdPMT1 or the Bradi1g36980 (BdPMT2) gene into Arabidopsis under the control of the Arabidopsis cinnamate-4-hydroxylase promoter boosted the p-coumaroylation of mature stems up to the grass lignin level (8% to 9% by weight), without any impact on plant development. The analysis of purified lignin fractions and the identification of diagnostic products confirmed that p-coumaric acid was associated with lignins. BdPMT1-driven p-coumaroylation was also obtained in the fah1 (deficient for ferulate 5-hydroxylase) and ccr1g (deficient for cinnamoyl-coenzyme A reductase) lines, albeit to a lower extent. Lignins from BdPMT1-expressing ccr1g lines were also found to be feruloylated. In Arabidopsis mature stems, substantial p-coumaroylation of lignins was achieved at the expense of lignin content and induced lignin structural alterations, with an unexpected increase of lignin units with free phenolic groups. This higher frequency of free phenolic groups in Arabidopsis lignins doubled their solubility in alkali at room temperature. These findings suggest that the formation of alkali-leachable lignin domains rich in free phenolic groups is favored when p-coumaroylated monolignols participate in lignification in a grass in a similar manner. PMID:26826222

Arabidopsis CDS blastp result: AK068893 [KOME

Lifescience Database Archive (English)

Full Text Available AK068893 J023001G24 At4g15090.1 far-red impaired response protein (FAR1) / far-red impai...red responsive protein (FAR1) identical to far-red impaired response protein FAR1 [Arabidopsis thaliana] gi|5764395|gb|AAD51282; contains Pfam:PF03101 domain: FAR1 family 1e-39 ...

What is 5G? Emerging 5G Mobile Services and Network Requirements

Directory of Open Access Journals (Sweden)

Heejung Yu

2017-10-01

Full Text Available In this paper, emerging 5G mobile services are investigated and categorized from the perspective of not service providers, but end-users. The development of 5G mobile services is based on an intensive analysis of the global trends in mobile services. Additionally, several indispensable service requirements, essential for realizing service scenarios presented, are described. To illustrate the changes in societies and in daily life in the 5G era, five megatrends, including the explosion of mobile data traffic, the rapid increase in connected devices, everything on the cloud, hyper-realistic media for convergence services and knowledge as a service enabled by big-data analysis, are examined. Based on such trends, we classify the new 5G services into five categories in terms of the end-users’ experience as follows: immersive 5G services, intelligent 5G services, omnipresent 5G services, autonomous 5G services and public 5G services. Moreover, several 5G service scenarios in each service category are presented, and essential technical requirements for realizing the aforementioned 5G services are suggested, along with a competitiveness analysis on 5G services/devices/network industries and the current condition of 5G technologies.

Arabidopsis CDS blastp result: AK107208 [KOME

Lifescience Database Archive (English)

Full Text Available Ala hydrolase, putative virtually identical to gr1-protein from [Arabidopsis thaliana] GI:3559811; similar t...AK107208 002-125-B11 At1g44350.1 IAA-amino acid hydrolase 6, putative (ILL6) / IAA-

Arabidopsis CDS blastp result: AK099152 [KOME

Lifescience Database Archive (English)

Full Text Available AK099152 J023070H02 At4g01900.1 P II nitrogen sensing protein (GLB I) identical to P II nitrogen... sensing protein GLB I (GI:7268574) [Arabidopsis thaliana]; similar to nitrogen regulatory prot

Arabidopsis CDS blastp result: AK068407 [KOME

Lifescience Database Archive (English)

Full Text Available AK068407 J013149B08 At4g01900.1 P II nitrogen sensing protein (GLB I) identical to P II nitrogen... sensing protein GLB I (GI:7268574) [Arabidopsis thaliana]; similar to nitrogen regulatory prot

Arabidopsis CDS blastp result: AK242707 [KOME

Lifescience Database Archive (English)

Full Text Available AK242707 J090040M15 At1g70550.2 68414.m08120 expressed protein similar to hypotheti...cal protein GB:AAD31338 [Arabidopsis thaliana] and to putative putative carboxyl-terminal peptidase GB:AAC16

Arabidopsis CDS blastp result: AK242707 [KOME

Lifescience Database Archive (English)

Full Text Available AK242707 J090040M15 At1g70550.1 68414.m08119 expressed protein similar to hypotheti...cal protein GB:AAD31338 [Arabidopsis thaliana] and to putative putative carboxyl-terminal peptidase GB:AAC16

Arabidopsis CDS blastp result: AK242472 [KOME

Lifescience Database Archive (English)

Full Text Available AK242472 J080303B22 At1g70550.2 68414.m08120 expressed protein similar to hypotheti...cal protein GB:AAD31338 [Arabidopsis thaliana] and to putative putative carboxyl-terminal peptidase GB:AAC16

Arabidopsis CDS blastp result: AK242472 [KOME

Lifescience Database Archive (English)

Full Text Available AK242472 J080303B22 At1g70550.1 68414.m08119 expressed protein similar to hypotheti...cal protein GB:AAD31338 [Arabidopsis thaliana] and to putative putative carboxyl-terminal peptidase GB:AAC16

Arabidopsis CDS blastp result: AK067891 [KOME

Lifescience Database Archive (English)

Full Text Available AK067891 J013124H21 At4g22260.1 alternative oxidase, putative / immutans protein (I...M) identical to IMMUTANS from Arabidopsis thaliana [gi:4138855]; contains Pfam profile PF01786 alternative oxidase 1e-110 ...

Functionally Similar WRKY Proteins Regulate Vacuolar Acidification in Petunia and Hair Development in Arabidopsis.

Science.gov (United States)

Verweij, Walter; Spelt, Cornelis E; Bliek, Mattijs; de Vries, Michel; Wit, Niek; Faraco, Marianna; Koes, Ronald; Quattrocchio, Francesca M

2016-03-01

The WD40 proteins ANTHOCYANIN11 (AN11) from petunia (Petunia hybrida) and TRANSPARENT TESTA GLABRA1 (TTG1) from Arabidopsis thaliana and associated basic helix-loop-helix (bHLH) and MYB transcription factors activate a variety of differentiation processes. In petunia petals, AN11 and the bHLH protein AN1 activate, together with the MYB protein AN2, anthocyanin biosynthesis and, together with the MYB protein PH4, distinct genes, such as PH1 and PH5, that acidify the vacuole. To understand how AN1 and AN11 activate anthocyanin biosynthetic and PH genes independently, we isolated PH3. We found that PH3 is a target gene of the AN11-AN1-PH4 complex and encodes a WRKY protein that can bind to AN11 and is required, in a feed-forward loop, together with AN11-AN1-PH4 for transcription of PH5. PH3 is highly similar to TTG2, which regulates hair development, tannin accumulation, and mucilage production in Arabidopsis. Like PH3, TTG2 can bind to petunia AN11 and the Arabidopsis homolog TTG1, complement ph3 in petunia, and reactivate the PH3 target gene PH5. Our findings show that the specificity of WD40-bHLH-MYB complexes is in part determined by interacting proteins, such as PH3 and TTG2, and reveal an unanticipated similarity in the regulatory circuitry that controls petunia vacuolar acidification and Arabidopsis hair development. © 2016 American Society of Plant Biologists. All rights reserved.

Arabidopsis female gametophyte gene expression map reveals similarities between plant and animal gametes.

Science.gov (United States)

Wuest, Samuel E; Vijverberg, Kitty; Schmidt, Anja; Weiss, Manuel; Gheyselinck, Jacqueline; Lohr, Miriam; Wellmer, Frank; Rahnenführer, Jörg; von Mering, Christian; Grossniklaus, Ueli

2010-03-23

The development of multicellular organisms is controlled by differential gene expression whereby cells adopt distinct fates. A spatially resolved view of gene expression allows the elucidation of transcriptional networks that are linked to cellular identity and function. The haploid female gametophyte of flowering plants is a highly reduced organism: at maturity, it often consists of as few as three cell types derived from a common precursor [1, 2]. However, because of its inaccessibility and small size, we know little about the molecular basis of cell specification and differentiation in the female gametophyte. Here we report expression profiles of all cell types in the mature Arabidopsis female gametophyte. Differentially expressed posttranscriptional regulatory modules and metabolic pathways characterize the distinct cell types. Several transcription factor families are overrepresented in the female gametophyte in comparison to other plant tissues, e.g., type I MADS domain, RWP-RK, and reproductive meristem transcription factors. PAZ/Piwi-domain encoding genes are upregulated in the egg, indicating a role of epigenetic regulation through small RNA pathways-a feature paralleled in the germline of animals [3]. A comparison of human and Arabidopsis egg cells for enrichment of functional groups identified several similarities that may represent a consequence of coevolution or ancestral gametic features. 2010 Elsevier Ltd. All rights reserved.

Introduction of a tryptophan side chain into subsite +1 enhances transglycosylation activity of a GH-18 chitinase from Arabidopsis thaliana, AtChiC

DEFF Research Database (Denmark)

Umemoto, Naoyuki; Ohnuma, Takayuki; Mizuhara, Mamiko

2013-01-01

A tryptophan side chain was introduced into subsite +1 of family GH-18 (class V) chitinases from Nicotiana tabacum and Arabidopsis thaliana (NtChiV and AtChiC, respectively) by the mutation of a glycine residue to tryptophan (G74W-NtChiV and G75W-AtChiC). The specific activity toward glycol chitin...... of the two mutant enzymes was 70-71% of that of the wild type. Using chitin oligosaccharides, (GlcNAc)(n) (n = 4, 5 and 6), as the substrates, we found the transglycosylation reaction to be significantly enhanced in G74W-NtChiV and G75W-AtChiC when compared with the corresponding wild-type enzymes....... The introduced tryptophan side chain might protect the oxazolinium ion intermediate from attack by a nucleophilic water molecule. The enhancement of transglycosylation activity was much more distinct in G75W-AtChiC than in G74W-NtChiV. Nuclear magnetic resonance titration experiments using the inactive double...

PNL1 and PNL2 : Arabidopsis homologs of maize PAN1

OpenAIRE

Clark, Lauren Gail

2010-01-01

PNL1 and PNL2 are the closest Arabidopsis relatives of maize pan1. pan1 and the PNL family of 11 genes encode leucine-rich repeat, receptor-like kinases, however none of these putative kinases is predicted to have actual kinase function, due to one or more amino acid substitutions in residues necessary for kinase function. Because PAN1 plays a role in subsidiary cell formation in maize, it is hypothesized that PNL1 and PNL2 are involved in stomatal formation in Arabidopsis. YFP fusions of the...

TaSK5, an abiotic stress-inducible GSK3/shaggy-like kinase from wheat, confers salt and drought tolerance in transgenic Arabidopsis.

Science.gov (United States)

Christov, Nikolai Kirilov; Christova, Petya Koeva; Kato, Hideki; Liu, Yuelin; Sasaki, Kentaro; Imai, Ryozo

2014-11-01

A novel cold-inducible GSK3/shaggy-like kinase, TaSK5, was isolated from winter wheat using a macroarray-based differential screening approach. TaSK5 showed high similarity to Arabidopsis subgroup I GSK3/shaggy-like kinases ASK-alpha, AtSK-gamma and ASK-epsilon. RNA gel blot analyses revealed TaSK5 induction by cold and NaCl treatments and to a lesser extent by drought treatment. TaSK5 functionally complemented the cold- and salt-sensitive phenotypes of a yeast GSK3/shaggy-like kinase mutant, △mck1. Transgenic Arabidopsis plants overexpressing TaSK5 cDNA showed enhanced tolerance to salt and drought stresses. By contrast, the tolerance of the transgenic plants to freezing stress was not altered. Microarray analysis revealed that a number of abiotic stress-inducible genes were constitutively induced in the transgenic Arabidopsis plants, suggesting that TaSK5 may function in a novel signal transduction pathway that appears to be unrelated to DREB1/CBF regulon and may involve crosstalk between abiotic and hormonal signals. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

GENE EXPRESSION CHANGES IN ARABIDOPSIS THALIANA SEEDLING ROOTS EXPOSED TO THE MUNITION HEXAHYDRO-1,3,5-TRINITRO-1,3,5-TRIAZINE

Science.gov (United States)

Arabidopsis thaliana root transcriptome responses to the munition, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), were assessed using serial analysis of gene expression (SAGE). Comparison of the transcriptional profile for the RDX response to a profile previously described for Ar...

Arabidopsis CDS blastp result: AK243131 [KOME

Lifescience Database Archive (English)

Full Text Available AK243131 J100030A12 At1g21450.1 68414.m02682 scarecrow-like transcription factor 1 ...(SCL1) identical to scarecrow-like 1 GB:AAF21043 GI:6644390 from [Arabidopsis thaliana] 4e-46 ...

Arabidopsis CDS blastp result: AK242412 [KOME

Lifescience Database Archive (English)

Full Text Available AK242412 J080076J05 At1g21450.1 68414.m02682 scarecrow-like transcription factor 1 ...(SCL1) identical to scarecrow-like 1 GB:AAF21043 GI:6644390 from [Arabidopsis thaliana] 1e-36 ...

Arabidopsis CDS blastp result: AK119904 [KOME

Lifescience Database Archive (English)

Full Text Available AK119904 002-182-A05 At3g10920.1 superoxide dismutase [Mn], mitochondrial (SODA) / manga...nese superoxide dismutase (MSD1) identical to manganese superoxide dismutase [Arabidopsis thaliana] gi|3273751|gb|AAC24832 9e-78 ...

Arabidopsis CDS blastp result: AK070528 [KOME

Lifescience Database Archive (English)

Full Text Available AK070528 J023060D13 At3g10920.1 superoxide dismutase [Mn], mitochondrial (SODA) / manga...nese superoxide dismutase (MSD1) identical to manganese superoxide dismutase [Arabidopsis thaliana] gi|3273751|gb|AAC24832 9e-99 ...

Arabidopsis CDS blastp result: AK104030 [KOME

Lifescience Database Archive (English)

Full Text Available AK104030 001-020-C01 At3g10920.1 superoxide dismutase [Mn], mitochondrial (SODA) / manga...nese superoxide dismutase (MSD1) identical to manganese superoxide dismutase [Arabidopsis thaliana] gi|3273751|gb|AAC24832 9e-99 ...

Arabidopsis CDS blastp result: AK104160 [KOME

Lifescience Database Archive (English)

Full Text Available AK104160 006-211-E09 At3g10920.1 superoxide dismutase [Mn], mitochondrial (SODA) / manga...nese superoxide dismutase (MSD1) identical to manganese superoxide dismutase [Arabidopsis thaliana] gi|3273751|gb|AAC24832 9e-99 ...

Ectodomain of plasmodesmata-localized protein 5 in Arabidopsis: expression, purification, crystallization and crystallographic analysis.

Science.gov (United States)

Wang, Xiaocui; Zhu, Peiyan; Qu, Shanshan; Zhao, Jie; Singh, Prashant K; Wang, Wei

2017-09-01

Plasmodesmata-localized protein 5 (PDLP5) is a cysteine-rich receptor-like protein which is localized on the plasmodesmata of Arabidopsis thaliana. Overexpression of PDLP5 can reduce the permeability of the plasmodesmata and further affect the cell-to-cell movement of viruses and macromolecules in plants. The ectodomain of PDLP5 contains two DUF26 domains; however, the function of these domains is still unknown. Here, the ectodomain of PDLP5 from Arabidopsis was cloned and overexpressed using an insect expression system and was then purified and crystallized. X-ray diffraction data were collected to 1.90 Å resolution and were indexed in space group P1, with unit-cell parameters a = 41.9, b = 48.1, c = 62.2 Å, α = 97.3, β = 103.1, γ = 99.7°. Analysis of the crystal content indicated that there are two molecules in the asymmetric unit, with a Matthews coefficient of 2.51 Å 3  Da -1 and a solvent content of 50.97%.

A role for circadian evening elements in cold-regulated gene expression in Arabidopsis.

Science.gov (United States)

Mikkelsen, Michael D; Thomashow, Michael F

2009-10-01

The plant transcriptome is dramatically altered in response to low temperature. The cis-acting DNA regulatory elements and trans-acting factors that regulate the majority of cold-regulated genes are unknown. Previous bioinformatic analysis has indicated that the promoters of cold-induced genes are enriched in the Evening Element (EE), AAAATATCT, a DNA regulatory element that has a role in circadian-regulated gene expression. Here we tested the role of EE and EE-like (EEL) elements in cold-induced expression of two Arabidopsis genes, CONSTANS-like 1 (COL1; At5g54470) and a gene encoding a 27-kDa protein of unknown function that we designated COLD-REGULATED GENE 27 (COR27; At5g42900). Mutational analysis indicated that the EE/EEL elements were required for cold induction of COL1 and COR27, and that their action was amplified through coupling with ABA response element (ABRE)-like (ABREL) motifs. An artificial promoter consisting solely of four EE motifs interspersed with three ABREL motifs was sufficient to impart cold-induced gene expression. Both COL1 and COR27 were found to be regulated by the circadian clock at warm growth temperatures and cold-induction of COR27 was gated by the clock. These results suggest that cold- and clock-regulated gene expression are integrated through regulatory proteins that bind to EE and EEL elements supported by transcription factors acting at ABREL sequences. Bioinformatic analysis indicated that the coupling of EE and EEL motifs with ABREL motifs is highly enriched in cold-induced genes and thus may constitute a DNA regulatory element pair with a significant role in configuring the low-temperature transcriptome.

Influence of EARLI1-like genes on flowering time and lignin synthesis of Arabidopsis thaliana.

Science.gov (United States)

Shi, Y; Zhang, X; Xu, Z-Y; Li, L; Zhang, C; Schläppi, M; Xu, Z-Q

2011-09-01

EARLI1 encodes a 14.7 kDa protein in the cell wall, is a member of the PRP (proline-rich protein) family and has multiple functions, including resistance to low temperature and fungal infection. RNA gel blot analyses in the present work indicated that expression of EARLI1-like genes, EARLI1, At4G12470 and At4G12490, was down-regulated in Col-FRI-Sf2 RNAi plants derived from transformation with Agrobacterium strain ABI, which contains a construct encoding a double-strand RNA targeting 8CM of EARLI1. Phenotype analyses revealed that Col-FRI-Sf2 RNAi plants of EARLI1 flowered earlier than Col-FRI-Sf2 wild-type plants. The average bolting time of Col-FRI-Sf2 and Col-FRI-Sf2 RNAi plants was 39.7 and 19.4 days, respectively, under a long-day photoperiod. In addition, there were significant differences in main stem length, internode number and rosette leaf number between Col-FRI-Sf2 and Col-FRI-Sf2 RNAi plants. RT-PCR showed that EARLI1-like genes might delay flowering time through the autonomous and long-day photoperiod pathways by maintaining the abundance of FLC transcripts. In Col-FRI-Sf2 RNAi plants, transcription of FLC was repressed, while expression of SOC1 and FT was activated. Microscopy observations showed that EARLI1-like genes were also associated with morphogenesis of leaf cells in Arabidopsis. Using histochemical staining, EARLI1-like genes were found to be involved in regulation of lignin synthesis in inflorescence stems, and Col-FRI-Sf2 and Col-FRI-Sf2 RNAi plants had 9.67% and 8.76% dry weight lignin, respectively. Expression analysis revealed that cinnamoyl-CoA reductase, a key enzyme in lignin synthesis, was influenced by EARLI1-like genes. These data all suggest that EARLI1-like genes could control the flowering process and lignin synthesis in Arabidopsis. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

Arabidopsis: an adequate model for dicot root systems?

Directory of Open Access Journals (Sweden)

Richard W Zobel

2016-02-01

Full Text Available The Arabidopsis root system is frequently considered to have only three classes of root: primary, lateral, and adventitious. Research with other plant species has suggested up to 8 different developmental/functional classes of root for a given plant root system. If Arabidopsis has only three classes of root, it may not be an adequate model for eudicot plant root systems. Recent research, however, can be interpreted to suggest that pre-flowering Arabidopsis does have at least five (5 of these classes of root. This then suggests that Arabidopsis root research can be considered an adequate model for eudicot plant root systems.

Regulatory Proteolysis in Arabidopsis-Pathogen Interactions.

Science.gov (United States)

Pogány, Miklós; Dankó, Tamás; Kámán-Tóth, Evelin; Schwarczinger, Ildikó; Bozsó, Zoltán

2015-09-24

Approximately two and a half percent of protein coding genes in Arabidopsis encode enzymes with known or putative proteolytic activity. Proteases possess not only common housekeeping functions by recycling nonfunctional proteins. By irreversibly cleaving other proteins, they regulate crucial developmental processes and control responses to environmental changes. Regulatory proteolysis is also indispensable in interactions between plants and their microbial pathogens. Proteolytic cleavage is simultaneously used both by plant cells, to recognize and inactivate invading pathogens, and by microbes, to overcome the immune system of the plant and successfully colonize host cells. In this review, we present available results on the group of proteases in the model plant Arabidopsis thaliana whose functions in microbial pathogenesis were confirmed. Pathogen-derived proteolytic factors are also discussed when they are involved in the cleavage of host metabolites. Considering the wealth of review papers available in the field of the ubiquitin-26S proteasome system results on the ubiquitin cascade are not presented. Arabidopsis and its pathogens are conferred with abundant sets of proteases. This review compiles a list of those that are apparently involved in an interaction between the plant and its pathogens, also presenting their molecular partners when available.

Arabidopsis CDS blastp result: AK242212 [KOME

Lifescience Database Archive (English)

Full Text Available AK242212 J075171E13 At3g29410.1 68416.m03695 terpene synthase/cyclase family protein similar to terpene... synthase GB:CAA72074 from [Arabidopsis thaliana], contains Pfam profile: PF01397 terpene synthase family 1e-21 ...

Arabidopsis CDS blastp result: AK289251 [KOME

Lifescience Database Archive (English)

Full Text Available AK289251 J100081E23 At4g16390.1 68417.m02481 chloroplastic RNA-binding protein P67,... putative nearly identical to 67kD chloroplastic RNA-binding protein, P67 [Arabidopsis thaliana] GI:9755842 6e-21 ...

Arabidopsis CDS blastp result: AK287737 [KOME

Lifescience Database Archive (English)

Full Text Available AK287737 J065143M09 At4g16390.1 68417.m02481 chloroplastic RNA-binding protein P67,... putative nearly identical to 67kD chloroplastic RNA-binding protein, P67 [Arabidopsis thaliana] GI:9755842 7e-14 ...

Arabidopsis CDS blastp result: AK288338 [KOME

Lifescience Database Archive (English)

Full Text Available AK288338 J090023E14 At4g16390.1 68417.m02481 chloroplastic RNA-binding protein P67,... putative nearly identical to 67kD chloroplastic RNA-binding protein, P67 [Arabidopsis thaliana] GI:9755842 9e-22 ...

Arabidopsis CDS blastp result: AK288935 [KOME

Lifescience Database Archive (English)

Full Text Available AK288935 J090082J19 At4g16390.1 68417.m02481 chloroplastic RNA-binding protein P67,... putative nearly identical to 67kD chloroplastic RNA-binding protein, P67 [Arabidopsis thaliana] GI:9755842 8e-21 ...

Arabidopsis CDS blastp result: AK241112 [KOME

Lifescience Database Archive (English)

Full Text Available AK241112 J065091K02 At4g16390.1 68417.m02481 chloroplastic RNA-binding protein P67,... putative nearly identical to 67kD chloroplastic RNA-binding protein, P67 [Arabidopsis thaliana] GI:9755842 1e-16 ...

Arabidopsis CDS blastp result: AK240855 [KOME

Lifescience Database Archive (English)

Full Text Available AK240855 J065021H02 At4g16390.1 68417.m02481 chloroplastic RNA-binding protein P67,... putative nearly identical to 67kD chloroplastic RNA-binding protein, P67 [Arabidopsis thaliana] GI:9755842 7e-25 ...

Arabidopsis CDS blastp result: AK288753 [KOME

Lifescience Database Archive (English)

Full Text Available AK288753 J090065M09 At4g16390.1 68417.m02481 chloroplastic RNA-binding protein P67,... putative nearly identical to 67kD chloroplastic RNA-binding protein, P67 [Arabidopsis thaliana] GI:9755842 3e-29 ...

Arabidopsis CDS blastp result: AK242890 [KOME

Lifescience Database Archive (English)

Full Text Available AK242890 J090079L19 At1g32180.1 68414.m03958 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-9 (gi:9622890) from Zea mays 1e-126 ...

Arabidopsis CDS blastp result: AK242585 [KOME

Lifescience Database Archive (English)

Full Text Available AK242585 J090010M20 At1g32180.1 68414.m03958 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-9 (gi:9622890) from Zea mays 1e-24 ...

Arabidopsis CDS blastp result: AK242585 [KOME

Lifescience Database Archive (English)

Full Text Available AK242585 J090010M20 At1g32180.1 68414.m03958 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-9 (gi:9622890) from Zea mays 3e-66 ...

Arabidopsis CDS blastp result: AK287434 [KOME

Lifescience Database Archive (English)

Full Text Available AK287434 J043012F24 At4g16390.1 68417.m02481 chloroplastic RNA-binding protein P67,... putative nearly identical to 67kD chloroplastic RNA-binding protein, P67 [Arabidopsis thaliana] GI:9755842 2e-27 ...

Arabidopsis CDS blastp result: AK241784 [KOME

Lifescience Database Archive (English)

Full Text Available AK241784 J065206N09 At4g16390.1 68417.m02481 chloroplastic RNA-binding protein P67,... putative nearly identical to 67kD chloroplastic RNA-binding protein, P67 [Arabidopsis thaliana] GI:9755842 4e-11 ...

Arabidopsis thaliana is a susceptible host plant for the holoparasite Cuscuta spec.

Science.gov (United States)

Birschwilks, Mandy; Sauer, Norbert; Scheel, Dierk; Neumann, Stefanie

2007-10-01

Arabidopsis thaliana and Cuscuta spec. represent a compatible host-parasite combination. Cuscuta produces a haustorium that penetrates the host tissue. In early stages of development the searching hyphae on the tip of the haustorial cone are connected to the host tissue by interspecific plasmodesmata. Ten days after infection, translocation of the fluorescent dyes, Texas Red (TR) and 5,6-carboxyfluorescein (CF), demonstrates the existence of a continuous connection between xylem and phloem of the host and parasite. Cuscuta becomes the dominant sink in this host-parasite system. Transgenic Arabidopsis plants expressing genes encoding the green fluorescent protein (GFP; 27 kDa) or a GFP-ubiquitin fusion (36 kDa), respectively, under the companion cell (CC)-specific AtSUC2 promoter were used to monitor the transfer of these proteins from the host sieve elements to those of Cuscuta. Although GFP is transferred unimpedly to the parasite, the GFP-ubiquitin fusion could not be detected in Cuscuta. A translocation of the GFP-ubiquitin fusion protein was found to be restricted to the phloem of the host, although a functional symplastic pathway exists between the host and parasite, as demonstrated by the transport of CF. These results indicate a peripheral size exclusion limit (SEL) between 27 and 36 kDa for the symplastic connections between host and Cuscuta sieve elements. Forty-six accessions of A. thaliana covering the entire range of its genetic diversity, as well as Arabidopsis halleri, were found to be susceptible towards Cuscuta reflexa.

High frequency of the IVS2-2A>G DNA sequence variation in SLC26A5, encoding the cochlear motor protein prestin, precludes its involvement in hereditary hearing loss

Directory of Open Access Journals (Sweden)

Pereira Fred A

2005-08-01

Full Text Available Abstract Background Cochlear outer hair cells change their length in response to variations in membrane potential. This capability, called electromotility, is believed to enable the sensitivity and frequency selectivity of the mammalian cochlea. Prestin is a transmembrane protein required for electromotility. Homozygous prestin knockout mice are profoundly hearing impaired. In humans, a single nucleotide change in SLC26A5, encoding prestin, has been reported in association with hearing loss. This DNA sequence variation, IVS2-2A>G, occurs in the exon 3 splice acceptor site and is expected to abolish splicing of exon 3. Methods To further explore the relationship between hearing loss and the IVS2-2A>G transition, and assess allele frequency, genomic DNA from hearing impaired and control subjects was analyzed by DNA sequencing. SLC26A5 genomic DNA sequences from human, chimp, rat, mouse, zebrafish and fruit fly were aligned and compared for evolutionary conservation of the exon 3 splice acceptor site. Alternative splice acceptor sites within intron 2 of human SLC26A5 were sought using a splice site prediction program from the Berkeley Drosophila Genome Project. Results The IVS2-2A>G variant was found in a heterozygous state in 4 of 74 hearing impaired subjects of Hispanic, Caucasian or uncertain ethnicity and 4 of 150 Hispanic or Caucasian controls (p = 0.45. The IVS2-2A>G variant was not found in 106 subjects of Asian or African American descent. No homozygous subjects were identified (n = 330. Sequence alignment of SLC26A5 orthologs demonstrated that the A nucleotide at position IVS2-2 is invariant among several eukaryotic species. Sequence analysis also revealed five potential alternative splice acceptor sites in intron 2 of human SLC26A5. Conclusion These data suggest that the IVS2-2A>G variant may not occur more frequently in hearing impaired subjects than in controls. The identification of five potential alternative splice acceptor sites in

Substrate specificity of Arabidopsis 3-ketoacyl-CoA synthases

International Nuclear Information System (INIS)

Blacklock, Brenda J.; Jaworski, Jan G.

2006-01-01

The very long chain fatty acids (VLCFA) incorporated into plant lipids are derived from the iterative addition of C2 units provided by malonyl-CoA to an acyl-CoA by the 3-ketoacyl-CoA synthase (KCS) component of a fatty acid elongase (FAE) complex. Mining of the Arabidopsis genome sequence database revealed 20 genes with homology to seed-specific FAE1 KCS. Eight of the 20 putative KCSs were cloned, expressed in yeast, and isolated as (His) 6 fusion proteins. Five of the eight (At1g71160, At1g19440, At1g07720, At5g04530, and At4g34250) had little or no activity with C16 to C20 substrates while three demonstrated activity with C16, C18, and C20 saturated acyl-CoA substrates. At1g01120 KCS (KCS1) and At2g26640 KCS had broad substrate specificities when assayed with saturated and mono-unsaturated C16 to C24 acyl-CoAs while At4g34510 KCS was specific for saturated fatty acyl-CoA substrates

The DNA translocase RAD5A acts independently of the other main DNA repair pathways, and requires both its ATPase and RING domain for activity in Arabidopsis thaliana.

Science.gov (United States)

Klemm, Tobias; Mannuß, Anja; Kobbe, Daniela; Knoll, Alexander; Trapp, Oliver; Dorn, Annika; Puchta, Holger

2017-08-01

Multiple pathways exist to repair DNA damage induced by methylating and crosslinking agents in Arabidopsis thaliana. The SWI2/SNF2 translocase RAD5A, the functional homolog of budding yeast Rad5 that is required for the error-free branch of post-replicative repair, plays a surprisingly prominent role in the repair of both kinds of lesions in Arabidopsis. Here we show that both the ATPase domain and the ubiquitination function of the RING domain of the Arabidopsis protein are essential for the cellular response to different forms of DNA damage. To define the exact role of RAD5A within the complex network of DNA repair pathways, we crossed the rad5a mutant line with mutants of different known repair factors of Arabidopsis. We had previously shown that RAD5A acts independently of two main pathways of replication-associated DNA repair defined by the helicase RECQ4A and the endonuclease MUS81. The enhanced sensitivity of all double mutants tested in this study indicates that the repair of damaged DNA by RAD5A also occurs independently of nucleotide excision repair (AtRAD1), single-strand break repair (AtPARP1), as well as microhomology-mediated double-strand break repair (AtTEB). Moreover, RAD5A can partially complement for a deficient AtATM-mediated DNA damage response in plants, as the double mutant shows phenotypic growth defects. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

Sequence and RT-PCR expression analysis of two peroxidases from Arabidopsis thaliana belonging to a novel evolutionary branch of plant perioxidases

DEFF Research Database (Denmark)

Kjærsgård, I.V.H.; Jespersen, H.M.; Rasmussen, Søren Kjærsgård

1997-01-01

cDNA clones encoding two new Arabidopsis thaliana peroxidases, ATP la and ATP 2a, have been identified by searching the Arabidopsis database of expressed sequence tags (dbEST). They represent a novel branch of hitherto uncharacterized plant peroxidases which is only 35% identical in amino acid...

Isolation and characterization of CNGC17 gene from Arabidopsis thaliana

International Nuclear Information System (INIS)

Yamagami, Mutsumi; Kobayashi, Daisuke; Hisamatsu, Shun'ichi

2007-01-01

Phytoremediation is a possible countermeasure for cleaning up soil contaminated by 137 Cs, and development of plants which can effectively absorb 137 Cs is important for it. It is expected that capability of Cs extraction from soil can be strengthened by genetic alteration of the Cs + root-uptake mechanism of plants. This study aimed at elucidating the uptake mechanism of Cs + for future genetic engineering. Plant roots take up Cs + from the soil solution via transport proteins at the plasma membrane of root cells. Voltage-insensitive cation channels (VICCs) are a possible transfer route of Cs + , and they are encoded by cyclic-nucleotide gated channel (CNGC) and glutamate receptor (GLR) gene families. The genome of Arabidopsis thaliana contains 20 CNGC genes. We have cloned a putative AtCNGC17 gene from cDNAs which were generated with total-RNA obtained from leaves of Arabidopsis thaliana by RT-PCR. The cDNA contained 2163 bp with an ORF that encoded a protein consisting of 721 amino acids residues. The plasmid prepared by the insertion of the gene under a Taq promoter was used to transform an E. coli deficient in the three major K + uptake systems (Kdp, Trk, and Kup). Only the E. coli with AtCNGC17 gene grew in low K + concentration minimal medium. This result suggested that the AtCNGC17 protein has a function of K + uptake. Growth rates of the E. coli cells expressing the gene were strongly inhibited by CsCl in low K + concentration minimal medium, suggesting that the AtCNGC17 transporter also carries Cs + . (author)

5G CHAMPION - rolling out 5G in 2018

OpenAIRE

Mueck, M.; Strinati, E.C.; Kim, I.-G.; Clemente, A.; Dore, J.-B.; Domenico, A. de; Kim, T.; Choi, T.; Chung, H.K.; Destino, G.; Pärssinen, A.; Pouttu, A.; Latva-aho, M.; Chuberre, N.; Gineste, M.

2016-01-01

The 5G CHAMPION Consortium will provide the first fully integrated and operational 5G prototype in 2018 - this effort is a major leap ahead compared to existing punctual technology trials, such as, e.g., Proof-of-Concept platforms focusing on mm Wave communication in specific bands, etc. This paper describes the overall set-up including a synergetic combination of technologies such as beamforming based mm Wave & Satellite service provisioning, virtualized infrastructure, software reconfigurat...

Arabidopsis CDS blastp result: AK065124 [KOME

Lifescience Database Archive (English)

Full Text Available AK065124 J013001P04 At1g44446.1 chlorophyll a oxygenase (CAO) / chlorophyll b synthase identical to chloroph...yll a oxygenase GI:5853117 from [Arabidopsis thaliana]; contains Pfam PF00355 Rieske [2Fe-2S] domain 0.0 ...

Arabidopsis CDS blastp result: AK067730 [KOME

Lifescience Database Archive (English)

Full Text Available AK067730 J013116K15 At1g44446.1 chlorophyll a oxygenase (CAO) / chlorophyll b synthase identical to chloroph...yll a oxygenase GI:5853117 from [Arabidopsis thaliana]; contains Pfam PF00355 Rieske [2Fe-2S] domain 0.0 ...

Arabidopsis CDS blastp result: AK063367 [KOME

Lifescience Database Archive (English)

Full Text Available AK063367 001-114-D11 At1g44446.1 chlorophyll a oxygenase (CAO) / chlorophyll b synthase identical to chlorop...hyll a oxygenase GI:5853117 from [Arabidopsis thaliana]; contains Pfam PF00355 Rieske [2Fe-2S] domain 0.0 ...

Arabidopsis CDS blastp result: AK064663 [KOME

Lifescience Database Archive (English)

Full Text Available AK064663 002-115-A10 At2g34450.1 high mobility group (HMG1/2) family protein simila...r to HMG protein [Arabidopsis thaliana] GI:2832361; contains Pfam profile PF00505: HMG (high mobility group) box 2e-27 ...

Arabidopsis CDS blastp result: AK242428 [KOME

Lifescience Database Archive (English)

Full Text Available AK242428 J080089P09 At2g41100.1 68415.m05076 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 8e-18 ...

Arabidopsis CDS blastp result: AK242346 [KOME

Lifescience Database Archive (English)

Full Text Available AK242346 J080012M07 At2g41100.1 68415.m05076 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 8e-44 ...

Arabidopsis CDS blastp result: AK242428 [KOME

Lifescience Database Archive (English)

Full Text Available AK242428 J080089P09 At2g41100.1 68415.m05076 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 2e-14 ...

Arabidopsis CDS blastp result: AK242428 [KOME

Lifescience Database Archive (English)

Full Text Available AK242428 J080089P09 At2g41100.2 68415.m05077 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 3e-16 ...

Arabidopsis CDS blastp result: AK242346 [KOME

Lifescience Database Archive (English)

Full Text Available AK242346 J080012M07 At2g41100.1 68415.m05076 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 4e-41 ...

Arabidopsis CDS blastp result: AK242346 [KOME

Lifescience Database Archive (English)

Full Text Available AK242346 J080012M07 At2g41100.2 68415.m05077 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 3e-26 ...

Arabidopsis CDS blastp result: AK243656 [KOME

Lifescience Database Archive (English)

Full Text Available AK243656 J100088L22 At2g41100.1 68415.m05076 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 1e-19 ...

Arabidopsis CDS blastp result: AK242346 [KOME

Lifescience Database Archive (English)

Full Text Available AK242346 J080012M07 At2g41100.2 68415.m05077 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 3e-44 ...

Arabidopsis CDS blastp result: AK243656 [KOME

Lifescience Database Archive (English)

Full Text Available AK243656 J100088L22 At2g41100.1 68415.m05076 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 2e-17 ...

Arabidopsis CDS blastp result: AK288095 [KOME

Lifescience Database Archive (English)

Full Text Available AK288095 J075191E21 At2g41100.1 68415.m05076 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 2e-16 ...

Arabidopsis CDS blastp result: AK242346 [KOME

Lifescience Database Archive (English)

Full Text Available AK242346 J080012M07 At2g41100.1 68415.m05076 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 3e-26 ...

Arabidopsis CDS blastp result: AK288095 [KOME

Lifescience Database Archive (English)

Full Text Available AK288095 J075191E21 At2g41100.2 68415.m05077 touch-responsive protein / calmodulin-related protein 3, touch...-induced (TCH3) identical to calmodulin-related protein 3, touch-induced SP:P25071 from [Arabidopsis thaliana] 2e-15 ...

Arabidopsis CDS blastp result: AK072001 [KOME

Lifescience Database Archive (English)

Full Text Available AK072001 J013094L17 At2g22670.2 auxin-responsive protein / indoleacetic acid-induce...d protein 8 (IAA8) identical to SP|Q38826 Auxin-responsive protein IAA8 (Indoleacetic acid-induced protein 8) {Arabidopsis thaliana} 2e-11 ...

Arabidopsis CDS blastp result: AK069892 [KOME

Lifescience Database Archive (English)

Full Text Available AK069892 J023039N11 At2g33310.1 auxin-responsive protein / indoleacetic acid-induce...d protein 13 (IAA13) identical to SP|Q38831 Auxin-responsive protein IAA13 (Indoleacetic acid-induced protein 13) {Arabidopsis thaliana} 3e-41 ...

Arabidopsis CDS blastp result: AK102396 [KOME

Lifescience Database Archive (English)

Full Text Available AK102396 J033092H03 At2g22670.1 auxin-responsive protein / indoleacetic acid-induce...d protein 8 (IAA8) identical to SP|Q38826 Auxin-responsive protein IAA8 (Indoleacetic acid-induced protein 8) {Arabidopsis thaliana} 2e-50 ...

Arabidopsis CDS blastp result: AK059838 [KOME

Lifescience Database Archive (English)

Full Text Available AK059838 006-206-C11 At3g04730.1 auxin-responsive protein / indoleacetic acid-induc...ed protein 16 (IAA16) identical to SP|O24407 Auxin-responsive protein IAA16 (Indoleacetic acid-induced protein 16) {Arabidopsis thaliana} 8e-45 ...

Arabidopsis CDS blastp result: AK061495 [KOME

Lifescience Database Archive (English)

Full Text Available AK061495 006-309-C06 At2g22670.1 auxin-responsive protein / indoleacetic acid-induc...ed protein 8 (IAA8) identical to SP|Q38826 Auxin-responsive protein IAA8 (Indoleacetic acid-induced protein 8) {Arabidopsis thaliana} 3e-50 ...

Arabidopsis CDS blastp result: AK099253 [KOME

Lifescience Database Archive (English)

Full Text Available AK099253 J013168H04 At2g22670.1 auxin-responsive protein / indoleacetic acid-induce...d protein 8 (IAA8) identical to SP|Q38826 Auxin-responsive protein IAA8 (Indoleacetic acid-induced protein 8) {Arabidopsis thaliana} 4e-51 ...

Arabidopsis CDS blastp result: AK063854 [KOME

Lifescience Database Archive (English)

Full Text Available AK063854 001-122-D03 At3g04730.1 auxin-responsive protein / indoleacetic acid-induc...ed protein 16 (IAA16) identical to SP|O24407 Auxin-responsive protein IAA16 (Indoleacetic acid-induced protein 16) {Arabidopsis thaliana} 2e-22 ...

Arabidopsis CDS blastp result: AK104018 [KOME

Lifescience Database Archive (English)

Full Text Available AK104018 001-007-H11 At2g22670.1 auxin-responsive protein / indoleacetic acid-induc...ed protein 8 (IAA8) identical to SP|Q38826 Auxin-responsive protein IAA8 (Indoleacetic acid-induced protein 8) {Arabidopsis thaliana} 4e-51 ...

Arabidopsis CDS blastp result: AK106181 [KOME

Lifescience Database Archive (English)

Full Text Available AK106181 001-208-D03 At2g22670.1 auxin-responsive protein / indoleacetic acid-induc...ed protein 8 (IAA8) identical to SP|Q38826 Auxin-responsive protein IAA8 (Indoleacetic acid-induced protein 8) {Arabidopsis thaliana} 4e-51 ...

Arabidopsis CDS blastp result: AK109363 [KOME

Lifescience Database Archive (English)

Full Text Available AK109363 006-206-E12 At2g22670.1 auxin-responsive protein / indoleacetic acid-induc...ed protein 8 (IAA8) identical to SP|Q38826 Auxin-responsive protein IAA8 (Indoleacetic acid-induced protein 8) {Arabidopsis thaliana} 2e-51 ...

Arabidopsis CDS blastp result: AK073365 [KOME

Lifescience Database Archive (English)

Full Text Available AK073365 J033030K18 At3g23030.1 auxin-responsive protein / indoleacetic acid-induce...d protein 2 (IAA2) identical to SP|P49678 Auxin-responsive protein IAA2 (Indoleacetic acid-induced protein 2) {Arabidopsis thaliana} 4e-20 ...

Arabidopsis CDS blastp result: AK066518 [KOME

Lifescience Database Archive (English)

Full Text Available AK066518 J013070M23 At2g46990.1 auxin-responsive protein / indoleacetic acid-induce...d protein 20 (IAA20) identical to SP|O24410 Auxin-responsive protein IAA20 (Indoleacetic acid-induced protein 20) {Arabidopsis thaliana} 3e-25 ...

Arabidopsis CDS blastp result: AK106121 [KOME

Lifescience Database Archive (English)

Full Text Available AK106121 001-207-E11 At2g22670.1 auxin-responsive protein / indoleacetic acid-induc...ed protein 8 (IAA8) identical to SP|Q38826 Auxin-responsive protein IAA8 (Indoleacetic acid-induced protein 8) {Arabidopsis thaliana} 7e-51 ...

Arabidopsis CDS blastp result: AK104802 [KOME

Lifescience Database Archive (English)

Full Text Available AK104802 001-040-C05 At2g33310.1 auxin-responsive protein / indoleacetic acid-induc...ed protein 13 (IAA13) identical to SP|Q38831 Auxin-responsive protein IAA13 (Indoleacetic acid-induced protein 13) {Arabidopsis thaliana} 3e-41 ...

Arabidopsis CDS blastp result: AK100988 [KOME

Lifescience Database Archive (English)

Full Text Available AK100988 J023145H17 At1g63440.1 copper-exporting ATPase, putative / responsive-to-a...ntagonist 1, putative / copper-transporting ATPase, putative similar to ATP dependent copper transporter SP|Q9S7J8 [Arabidopsis thaliana] 0.0 ...

Arabidopsis CDS blastp result: AK063759 [KOME

Lifescience Database Archive (English)

Full Text Available AK063759 001-121-A10 At1g63440.1 copper-exporting ATPase, putative / responsive-to-...antagonist 1, putative / copper-transporting ATPase, putative similar to ATP dependent copper transporter SP|Q9S7J8 [Arabidopsis thaliana] 0.0 ...

Arabidopsis CDS blastp result: AK072990 [KOME

Lifescience Database Archive (English)

Full Text Available AK072990 J023144D18 At1g63440.1 copper-exporting ATPase, putative / responsive-to-a...ntagonist 1, putative / copper-transporting ATPase, putative similar to ATP dependent copper transporter SP|Q9S7J8 [Arabidopsis thaliana] 0.0 ...

The alpha-subunit of the Arabidopsis heterotrimeric G protein, GPA1, is a regulator of transpiration efficiency.

Science.gov (United States)

Nilson, Sarah E; Assmann, Sarah M

2010-04-01

Land plants must balance CO2 assimilation with transpiration in order to minimize drought stress and maximize their reproductive success. The ratio of assimilation to transpiration is called transpiration efficiency (TE). TE is under genetic control, although only one specific gene, ERECTA, has been shown to regulate TE. We have found that the alpha-subunit of the heterotrimeric G protein in Arabidopsis (Arabidopsis thaliana), GPA1, is a regulator of TE. gpa1 mutants, despite having guard cells that are hyposensitive to abscisic acid-induced inhibition of stomatal opening, have increased TE under ample water and drought stress conditions and when treated with exogenous abscisic acid. Leaf-level gas-exchange analysis shows that gpa1 mutants have wild-type assimilation versus internal CO2 concentration responses but exhibit reduced stomatal conductance compared with ecotype Columbia at ambient and below-ambient internal CO2 concentrations. The increased TE and reduced whole leaf stomatal conductance of gpa1 can be primarily attributed to stomatal density, which is reduced in gpa1 mutants. GPA1 regulates stomatal density via the control of epidermal cell size and stomata formation. GPA1 promoter::beta-glucuronidase lines indicate that the GPA1 promoter is active in the stomatal cell lineage, further supporting a function for GPA1 in stomatal development in true leaves.

Inferring transcriptional gene regulation network of starch metabolism in Arabidopsis thaliana leaves using graphical Gaussian model

Directory of Open Access Journals (Sweden)

Ingkasuwan Papapit

2012-08-01

Full Text Available Abstract Background Starch serves as a temporal storage of carbohydrates in plant leaves during day/night cycles. To study transcriptional regulatory modules of this dynamic metabolic process, we conducted gene regulation network analysis based on small-sample inference of graphical Gaussian model (GGM. Results Time-series significant analysis was applied for Arabidopsis leaf transcriptome data to obtain a set of genes that are highly regulated under a diurnal cycle. A total of 1,480 diurnally regulated genes included 21 starch metabolic enzymes, 6 clock-associated genes, and 106 transcription factors (TF. A starch-clock-TF gene regulation network comprising 117 nodes and 266 edges was constructed by GGM from these 133 significant genes that are potentially related to the diurnal control of starch metabolism. From this network, we found that β-amylase 3 (b-amy3: At4g17090, which participates in starch degradation in chloroplast, is the most frequently connected gene (a hub gene. The robustness of gene-to-gene regulatory network was further analyzed by TF binding site prediction and by evaluating global co-expression of TFs and target starch metabolic enzymes. As a result, two TFs, indeterminate domain 5 (AtIDD5: At2g02070 and constans-like (COL: At2g21320, were identified as positive regulators of starch synthase 4 (SS4: At4g18240. The inference model of AtIDD5-dependent positive regulation of SS4 gene expression was experimentally supported by decreased SS4 mRNA accumulation in Atidd5 mutant plants during the light period of both short and long day conditions. COL was also shown to positively control SS4 mRNA accumulation. Furthermore, the knockout of AtIDD5 and COL led to deformation of chloroplast and its contained starch granules. This deformity also affected the number of starch granules per chloroplast, which increased significantly in both knockout mutant lines. Conclusions In this study, we utilized a systematic approach of microarray

Arabidopsis CDS blastp result: AK108796 [KOME

Lifescience Database Archive (English)

Full Text Available AK108796 002-151-C01 At2g25320.1 meprin and TRAF homology domain-containing protein / MATH... domain-containing protein weak similarity to ubiquitin-specific protease 12 [Arabidopsis thaliana] GI:11993471; contains Pfam profile PF00917: MATH domain 3e-97 ...

Arabidopsis CDS blastp result: AK072243 [KOME

Lifescience Database Archive (English)

Full Text Available AK072243 J023003N10 At1g07110.1 fructose-6-phosphate 2-kinase / fructose-2,6-bispho...sphatase (F2KP) identical to fructose-6-phosphate 2-kinase/fructose-2,6-bisphosphatase (F2KP) [Arabidopsis thaliana] GI:13096098 0.0 ...

Arabidopsis CDS blastp result: AK065086 [KOME

Lifescience Database Archive (English)

Full Text Available AK065086 J013001L18 At1g07110.1 fructose-6-phosphate 2-kinase / fructose-2,6-bispho...sphatase (F2KP) identical to fructose-6-phosphate 2-kinase/fructose-2,6-bisphosphatase (F2KP) [Arabidopsis thaliana] GI:13096098 0.0 ...

Arabidopsis CDS blastp result: AK069285 [KOME

Lifescience Database Archive (English)

Full Text Available AK069285 J023011N22 At1g07110.1 fructose-6-phosphate 2-kinase / fructose-2,6-bispho...sphatase (F2KP) identical to fructose-6-phosphate 2-kinase/fructose-2,6-bisphosphatase (F2KP) [Arabidopsis thaliana] GI:13096098 0.0 ...

Arabidopsis CDS blastp result: AK068433 [KOME

Lifescience Database Archive (English)

Full Text Available AK068433 J013156D16 At1g20620.2 catalase 3 (SEN2) almost identical to catalase 3 SP...:Q42547, GI:3123188 from [Arabidopsis thaliana]; identical to catalase 3 (SEN2) mRNA, partial cds GI:3158369 1e-63 ...

Arabidopsis and the Genetic Potential for the Phytoremediation of Toxic Elemental and Organic Pollutants

Science.gov (United States)

Cobbett, Christopher S.; Meagher, Richard B.

2002-01-01

In a process called phytoremediation, plants can be used to extract, detoxify, and/or sequester toxic pollutants from soil, water, and air. Phytoremediation may become an essential tool in cleaning the environment and reducing human and animal exposure to potential carcinogens and other toxins. Arabidopsis has provided useful information about the genetic, physiological, and biochemical mechanisms behind phytoremediation, and it is an excellent model genetic organism to test foreign gene expression. This review focuses on Arabidopsis studies concerning: 1) the remediation of elemental pollutants; 2) the remediation of organic pollutants; and 3) the phytoremediation genome. Elemental pollutants include heavy metals and metalloids (e.g., mercury, lead, cadmium, arsenic) that are immutable. The general goal of phytoremediation is to extract, detoxify, and hyperaccumulate elemental pollutants in above-ground plant tissues for later harvest. A few dozen Arabidopsis genes and proteins that play direct roles in the remediation of elemental pollutants are discussed. Organic pollutants include toxic chemicals such as benzene, benzo(a)pyrene, polychlorinated biphenyls, trichloroethylene, trinitrotoluene, and dichlorodiphenyltrichloroethane. Phytoremediation of organic pollutants is focused on their complete mineralization to harmless products, however, less is known about the potential of plants to act on complex organic chemicals. A preliminary survey of the Arabidopsis genome suggests that as many as 700 genes encode proteins that have the capacity to act directly on environmental pollutants or could be modified to do so. The potential of the phytoremediation proteome to be used to reduce human exposure to toxic pollutants appears to be enormous and untapped. PMID:22303204

Characterization of an AtCCX5 gene from Arabidopsis thaliana that involves in high-affinity K+ uptake and Na+ transport in yeast

International Nuclear Information System (INIS)

Zhang, Xinxin; Zhang, Min; Takano, Tetsuo; Liu, Shenkui

2011-01-01

Highlights: → The AtCCX5 protein coding a putative cation calcium exchanger was characterized. → AtCCX5 expressed in yeast was localized in the plasma membrane and nuclear periphery. → AtCCX5 protein did not show the same transport properties as the CAXs. → AtCCX5 protein involves in mediating high-affinity K + uptake in yeast. → AtCCX5 protein also involves in Na + transport in yeast. -- Abstract: The gene for a putative cation calcium exchanger (CCX) from Arabidopsis thaliana, AtCCX5, was cloned and its function was analyzed in yeast. Green fluorescent protein-tagged AtCCX5 expressed in yeast was localized in the plasma membrane and nuclear periphery. The yeast transformants expressing AtCCX5 were created and their growth in the presence of various cations (K + , Na + , Ca 2+ , Mg 2+ , Fe 2+ , Cu 2+ , Co 2+ , Cd 2+ , Mn 2+ , Ba 2+ , Ni 2+ , Zn 2+ , and Li + ) were analyzed. AtCCX5 expression was found to affect the response to K + and Na + in yeast. The AtCCX5 transformant also showed a little better growth to Zn 2+ . The yeast mutant 9.3 expressing AtCCX5 restored growth of the mutant on medium with low K + (0.5 mM), and also suppressed its Na + sensitivity. Ion uptake experiments showed that AtCCX5 mediated relatively high-affinity K + uptake and was also involved in Na + transport in yeast. Taken together, these findings suggest that the AtCCX5 is a novel transport protein involves in mediating high-affinity K + uptake and Na + transport in yeast.

Calcium dynamics in root cells of Arabidopsis thaliana visualized with selective plane illumination microscopy.

Directory of Open Access Journals (Sweden)

Alex Costa

Full Text Available Selective Plane Illumination Microscopy (SPIM is an imaging technique particularly suited for long term in-vivo analysis of transparent specimens, able to visualize small organs or entire organisms, at cellular and eventually even subcellular resolution. Here we report the application of SPIM in Calcium imaging based on Förster Resonance Energy Transfer (FRET. Transgenic Arabidopsis plants expressing the genetically encoded-FRET-based Ca(2+ probe Cameleon, in the cytosol or nucleus, were used to demonstrate that SPIM enables ratiometric fluorescence imaging at high spatial and temporal resolution, both at tissue and single cell level. The SPIM-FRET technique enabled us to follow nuclear and cytosolic Ca(2+ dynamics in Arabidopsis root tip cells, deep inside the organ, in response to different stimuli. A relevant physiological phenomenon, namely Ca(2+ signal percolation, predicted in previous studies, has been directly visualized.

A circadian clock-regulated toggle switch explains AtGRP7 and AtGRP8 oscillations in Arabidopsis thaliana.

Directory of Open Access Journals (Sweden)

Christoph Schmal

Full Text Available The circadian clock controls many physiological processes in higher plants and causes a large fraction of the genome to be expressed with a 24h rhythm. The transcripts encoding the RNA-binding proteins AtGRP7 (Arabidopsis thaliana Glycine Rich Protein 7 and AtGRP8 oscillate with evening peaks. The circadian clock components CCA1 and LHY negatively affect AtGRP7 expression at the level of transcription. AtGRP7 and AtGRP8, in turn, negatively auto-regulate and reciprocally cross-regulate post-transcriptionally: high protein levels promote the generation of an alternative splice form that is rapidly degraded. This clock-regulated feedback loop has been proposed to act as a molecular slave oscillator in clock output. While mathematical models describing the circadian core oscillator in Arabidopsis thaliana were introduced recently, we propose here the first model of a circadian slave oscillator. We define the slave oscillator in terms of ordinary differential equations and identify the model's parameters by an optimization procedure based on experimental results. The model successfully reproduces the pertinent experimental findings such as waveforms, phases, and half-lives of the time-dependent concentrations. Furthermore, we obtain insights into possible mechanisms underlying the observed experimental dynamics: the negative auto-regulation and reciprocal cross-regulation via alternative splicing could be responsible for the sharply peaking waveforms of the AtGRP7 and AtGRP8 mRNA. Moreover, our results suggest that the AtGRP8 transcript oscillations are subordinated to those of AtGRP7 due to a higher impact of AtGRP7 protein on alternative splicing of its own and of the AtGRP8 pre-mRNA compared to the impact of AtGRP8 protein. Importantly, a bifurcation analysis provides theoretical evidence that the slave oscillator could be a toggle switch, arising from the reciprocal cross-regulation at the post-transcriptional level. In view of this

A Cytosolic Arabidopsis d-Xylulose Kinase Catalyzes the Phosphorylation of 1-Deoxy-d-Xylulose into a Precursor of the Plastidial Isoprenoid Pathway1

Science.gov (United States)

Hemmerlin, Andréa; Tritsch, Denis; Hartmann, Michael; Pacaud, Karine; Hoeffler, Jean-François; van Dorsselaer, Alain; Rohmer, Michel; Bach, Thomas J.

2006-01-01

Plants are able to integrate exogenous 1-deoxy-d-xylulose (DX) into the 2C-methyl-d-erythritol 4-phosphate pathway, implicated in the biosynthesis of plastidial isoprenoids. Thus, the carbohydrate needs to be phosphorylated into 1-deoxy-d-xylulose 5-phosphate and translocated into plastids, or vice versa. An enzyme capable of phosphorylating DX was partially purified from a cell-free Arabidopsis (Arabidopsis thaliana) protein extract. It was identified by mass spectrometry as a cytosolic protein bearing d-xylulose kinase (XK) signatures, already suggesting that DX is phosphorylated within the cytosol prior to translocation into the plastids. The corresponding cDNA was isolated and enzymatic properties of a recombinant protein were determined. In Arabidopsis, xylulose kinases are encoded by a small gene family, in which only two genes are putatively annotated. The additional gene is coding for a protein targeted to plastids, as was proved by colocalization experiments using green fluorescent protein fusion constructs. Functional complementation assays in an Escherichia coli strain deleted in xk revealed that the cytosolic enzyme could exclusively phosphorylate xylulose in vivo, not the enzyme that is targeted to plastids. xk activities could not be detected in chloroplast protein extracts or in proteins isolated from its ancestral relative Synechocystis sp. PCC 6803. The gene encoding the plastidic protein annotated as “xylulose kinase” might in fact yield an enzyme having different phosphorylation specificities. The biochemical characterization and complementation experiments with DX of specific Arabidopsis knockout mutants seedlings treated with oxo-clomazone, an inhibitor of 1-deoxy-d-xylulose 5-phosphate synthase, further confirmed that the cytosolic protein is responsible for the phosphorylation of DX in planta. PMID:16920870

Challenges to 5G standardization

DEFF Research Database (Denmark)

Mihovska, Albena D.; Prasad, Ramjee

2013-01-01

Interoperable, ubiquitous and dynamic are key objectives for fifth-generation (5G) communication systems and applications. These characteristics are also at the core of the main challenges that researchers, manufacturers, regulators and standardization bodies face when designing targeted strategies...... for the successful deployment of 5G enabling technologies....

Methyl transfer in glucosinolate biosynthesis mediated by indole glucosinolate O-Methyltransferase 5

DEFF Research Database (Denmark)

Pfalz, Marina; Mukhaimar, Maisara; Perreau, François

2016-01-01

in position 1 (1-IG modification) or 4 (4-IG modification). Products of the 4-IG modification pathway mediate plant-enemy interactions and are particularly important for Arabidopsis innate immunity. While CYP81Fs encoding cytochrome P450 monooxygenases and IGMTs encoding indole glucosinolate O...... with moderate similarity to previously characterized IGMTs, encodes the methyltransferase that is responsible for the conversion of 1OHI3M to 1MOI3M. Disruption of IGMT5 function increases resistance against the root-knot nematode Meloidogyne javanica and suggests a potential role for the 1-IG modification...

Arabidopsis CDS blastp result: AK106106 [KOME

Lifescience Database Archive (English)

Full Text Available AK106106 001-207-C12 At1g07110.1 fructose-6-phosphate 2-kinase / fructose-2,6-bisph...osphatase (F2KP) identical to fructose-6-phosphate 2-kinase/fructose-2,6-bisphosphatase (F2KP) [Arabidopsis thaliana] GI:13096098 9e-39 ...

Arabidopsis CDS blastp result: AK105066 [KOME

Lifescience Database Archive (English)

Full Text Available AK105066 001-044-F12 At1g07110.1 fructose-6-phosphate 2-kinase / fructose-2,6-bisph...osphatase (F2KP) identical to fructose-6-phosphate 2-kinase/fructose-2,6-bisphosphatase (F2KP) [Arabidopsis thaliana] GI:13096098 1e-166 ...

Identification of a novel group of putative Arabidopsis thaliana beta-(1,3)-galactosyltransferases

DEFF Research Database (Denmark)

Qu, Yongmei; Egelund, Jack; Gilson, Paul R

2008-01-01

To begin biochemical and molecular studies on the biosynthesis of the type II arabinogalactan chains on arabinogalactan-proteins (AGPs), we adopted a bioinformatic approach to identify and systematically characterise the putative galactosyltransferases (GalTs) responsible for synthesizing the beta......-(1,3)-Gal linkage from CAZy GT-family-31 from Arabidopsis thaliana. These analyses confirmed that 20 members of the GT-31 family contained domains/motifs typical of biochemically characterised beta-(1,3)-GTs from mammalian systems. Microarray data confirm that members of this family are expressed......,3)-GalT activity. This bioinformatic/molecular study of CAZy GT-family-31 was validated by the recent report of Strasser et al. (Plant Cell 19:2278-2292, 2007) that another member of this family (At1g26810; GALT1) encodes a beta-(1,3)-GalT involved in the biosynthesis of the Lewis a epitope of N...

Characterization of the snowy cotyledon 1 mutant of Arabidopsis thaliana: the impact of chloroplast elongation factor G on chloroplast development and plant vitality.

Science.gov (United States)

Albrecht, Verónica; Ingenfeld, Anke; Apel, Klaus

2006-03-01

During seedling development chloroplast formation marks the transition from heterotrophic to autotrophic growth. The development and activity of chloroplasts may differ in cotyledons that initially serve as a storage organ and true leaves whose primary function is photosynthesis. A genetic screen was used for the identification of genes that affect selectively chloroplast function in cotyledons of Arabidopsis thaliana. Several mutants exhibiting pale cotyledons and green true leaves were isolated and dubbed snowy cotyledon (sco). One of the mutants, sco1, was characterized in more detail. The mutated gene was identified using map-based cloning. The mutant contains a point mutation in a gene encoding the chloroplast elongation factor G, leading to an amino acid exchange within the predicted 70S ribosome-binding domain. The mutation results in a delay in the onset of germination. At this early developmental stage embryos still contain undifferentiated proplastids, whose proper function seems necessary for seed germination. In light-grown sco1 seedlings the greening of cotyledons is severely impaired, whereas the following true leaves develop normally as in wild-type plants. Despite this apparent similarity of chloroplast development in true leaves of mutant and wild-type plants various aspects of mature plant development are also affected by the sco1 mutation such as the onset of flowering, the growth rate, and seed production. The onset of senescence in the mutant and the wild-type plants occurs, however, at the same time, suggesting that in the mutant this particular developmental step does not seem to suffer from reduced protein translation efficiency in chloroplasts.

Arabidopsis CDS blastp result: AK119645 [KOME

Lifescience Database Archive (English)

Full Text Available PF|00847 AP2 domain; identical to cDNA enhancer of shoot regeneration ESR1 GI:18028939, enhancer of shoot regeneration ESR1 [Arabidopsis thaliana] GI:18028940 1e-10 ... ...ve / enhancer of shoot regeneration (ESR1) similar to gb|D38124 EREBP-3 from Nicotiana tabacum and contains ...AK119645 002-130-G05 At1g12980.1 AP2 domain-containing transcription factor, putati

Site-directed mutagenesis of the Arabidopsis heterotrimeric G protein β subunit suggests divergent mechanisms of effector activation between plant and animal G proteins.

Science.gov (United States)

Chakravorty, David; Trusov, Yuri; Botella, José Ramón

2012-03-01

Heterotrimeric G proteins are integral components of signal transduction in humans and other mammals and have been therefore extensively studied. However, while they are known to mediate many processes, much less is currently known about the effector pathways and molecular mechanisms used by these proteins to regulate effectors in plants. We designed a complementation strategy to study G protein signaling in Arabidopsis thaliana, particularly the mechanism of action of AGB1, the sole identified β subunit. We used biochemical and effector regulation data from human G protein studies to identify four potentially important residues for site-directed mutagenesis (T65, M111, D250 and W361 of AGB1). Each residue was individually mutated and the resulting mutated protein introduced in the agb1-2 mutant background under the control of the native AGB1 promoter. Interestingly, even though these mutations have been shown to have profound effects on effector signaling in humans, all the mutated subunits were able to restore thirteen of the fifteen Gβ-deficient phenotypes characterized in this study. Only one mutated protein, T65A was unable to complement the hypersensitivity to mannitol during germination observed in agb1 mutants; while only D250A failed to restore lateral root numbers in the agb1 mutant to wild-type levels. Our results suggest that the mechanisms used in mammalian G protein signaling are not well conserved in plant G protein signaling, and that either the effectors used by plant G proteins, or the mechanisms used to activate them, are at least partially divergent from the well-studied mammalian G proteins.

Spatio-Temporal Expression Patterns of Arabidopsis thaliana and Medicago truncatula Defensin-Like Genes

Science.gov (United States)

Nallu, Sumitha; Wang, Lin; Botanga, Christopher J.; Gomez, S. Karen; Costa, Liliana M.; Harrison, Maria J.; Samac, Deborah A.; Glazebrook, Jane; Katagiri, Fumiaki; Gutierrez-Marcos, Jose F.; VandenBosch, Kathryn A.

2013-01-01

Plant genomes contain several hundred defensin-like (DEFL) genes that encode short cysteine-rich proteins resembling defensins, which are well known antimicrobial polypeptides. Little is known about the expression patterns or functions of many DEFLs because most were discovered recently and hence are not well represented on standard microarrays. We designed a custom Affymetrix chip consisting of probe sets for 317 and 684 DEFLs from Arabidopsis thaliana and Medicago truncatula, respectively for cataloging DEFL expression in a variety of plant organs at different developmental stages and during symbiotic and pathogenic associations. The microarray analysis provided evidence for the transcription of 71% and 90% of the DEFLs identified in Arabidopsis and Medicago, respectively, including many of the recently annotated DEFL genes that previously lacked expression information. Both model plants contain a subset of DEFLs specifically expressed in seeds or fruits. A few DEFLs, including some plant defensins, were significantly up-regulated in Arabidopsis leaves inoculated with Alternaria brassicicola or Pseudomonas syringae pathogens. Among these, some were dependent on jasmonic acid signaling or were associated with specific types of immune responses. There were notable differences in DEFL gene expression patterns between Arabidopsis and Medicago, as the majority of Arabidopsis DEFLs were expressed in inflorescences, while only a few exhibited root-enhanced expression. By contrast, Medicago DEFLs were most prominently expressed in nitrogen-fixing root nodules. Thus, our data document salient differences in DEFL temporal and spatial expression between Arabidopsis and Medicago, suggesting distinct signaling routes and distinct roles for these proteins in the two plant species. PMID:23527067

Spatio-temporal expression patterns of Arabidopsis thaliana and Medicago truncatula defensin-like genes.

Directory of Open Access Journals (Sweden)

Mesfin Tesfaye

Full Text Available Plant genomes contain several hundred defensin-like (DEFL genes that encode short cysteine-rich proteins resembling defensins, which are well known antimicrobial polypeptides. Little is known about the expression patterns or functions of many DEFLs because most were discovered recently and hence are not well represented on standard microarrays. We designed a custom Affymetrix chip consisting of probe sets for 317 and 684 DEFLs from Arabidopsis thaliana and Medicago truncatula, respectively for cataloging DEFL expression in a variety of plant organs at different developmental stages and during symbiotic and pathogenic associations. The microarray analysis provided evidence for the transcription of 71% and 90% of the DEFLs identified in Arabidopsis and Medicago, respectively, including many of the recently annotated DEFL genes that previously lacked expression information. Both model plants contain a subset of DEFLs specifically expressed in seeds or fruits. A few DEFLs, including some plant defensins, were significantly up-regulated in Arabidopsis leaves inoculated with Alternaria brassicicola or Pseudomonas syringae pathogens. Among these, some were dependent on jasmonic acid signaling or were associated with specific types of immune responses. There were notable differences in DEFL gene expression patterns between Arabidopsis and Medicago, as the majority of Arabidopsis DEFLs were expressed in inflorescences, while only a few exhibited root-enhanced expression. By contrast, Medicago DEFLs were most prominently expressed in nitrogen-fixing root nodules. Thus, our data document salient differences in DEFL temporal and spatial expression between Arabidopsis and Medicago, suggesting distinct signaling routes and distinct roles for these proteins in the two plant species.

α/sub i/-3 cDNA encodes the α subunit of G/sub k/, the stimulatory G protein of receptor-regulated K+ channels

International Nuclear Information System (INIS)

Codina, J.; Olate, J.; Abramowitz, J.; Mattera, R.; Cook, R.G.; Birnbaumer, L.

1988-01-01

cDNA cloning has identified the presence in the human genome of three genes encoding α subunits of pertussis toxin substrates, generically called G/sub i/. They are named α/sub i/-1, α/sub i/-2 and α/sub i/-3. However, none of these genes has been functionally identified with any of the α subunits of several possible G proteins, including pertussis toxin-sensitive G/sub p/'s, stimulatory to phospholipase C or A 2 , G/sub i/, inhibitory to adenylyl cyclase, or G/sub k/, stimulatory to a type of K + channels. The authors now report the nucleotide sequence and the complete predicted amino acid sequence of human liver α/sub i/-3 and the partial amino acid sequence of proteolytic fragments of the α subunit of human erythrocyte G/sub k/. The amino acid sequence of the proteolytic fragment is uniquely encoded by the cDNA of α/sub i/-3, thus identifying it as α/sub k/. The probable identity of α/sub i/-1 with α/sub p/ and possible roles for α/sub i/-2, as well as additional roles for α/sub i/-1 and α/sub i/-3 (α/sub k/) are discussed

Synthesis of Hydroxylated Sterols in Transgenic Arabidopsis Plants Alters Growth and Steroid Metabolism1[C][W][OA

Science.gov (United States)

Beste, Lisa; Nahar, Nurun; Dalman, Kerstin; Fujioka, Shozo; Jonsson, Lisbeth; Dutta, Paresh C.; Sitbon, Folke

2011-01-01

To explore mechanisms in plant sterol homeostasis, we have here increased the turnover of sterols in Arabidopsis (Arabidopsis thaliana) and potato (Solanum tuberosum) plants by overexpressing four mouse cDNA encoding cholesterol hydroxylases (CHs), hydroxylating cholesterol at the C-7, C-24, C-25, or C-27 positions. Compared to the wild type, the four types of Arabidopsis transformant showed varying degrees of phenotypic alteration, the strongest one being in CH25 lines, which were dark-green dwarfs resembling brassinosteroid-related mutants. Gas chromatography-mass spectrometry analysis of extracts from wild-type Arabidopsis plants revealed trace levels of α and β forms of 7-hydroxycholesterol, 7-hydroxycampesterol, and 7-hydroxysitosterol. The expected hydroxycholesterol metabolites in CH7-, CH24-, and CH25 transformants were identified and quantified using gas chromatography-mass spectrometry. Additional hydroxysterol forms were also observed, particularly in CH25 plants. In CH24 and CH25 lines, but not in CH7 ones, the presence of hydroxysterols was correlated with a considerable alteration of the sterol profile and an increased sterol methyltransferase activity in microsomes. Moreover, CH25 lines contained clearly reduced levels of brassinosteroids, and displayed an enhanced drought tolerance. Equivalent transformations of potato plants with the CH25 construct increased hydroxysterol levels, but without the concomitant alteration of growth and sterol profiles observed in Arabidopsis. The results suggest that an increased hydroxylation of cholesterol and/or other sterols in Arabidopsis triggers compensatory processes, acting to maintain sterols at adequate levels. PMID:21746809

Biochemical and genetic characterization of three molybdenum cofactor hydroxylases in Arabidopsis thaliana

DEFF Research Database (Denmark)

Hoff, Tine; Frandsen, Gitte Inselmann; Rocher, Anne

1998-01-01

Aldehyde oxidases and xanthine dehydrogenases/oxidases belong to the molybdenum cofactor dependent hydroxylase class of enzymes. Zymograms show that Arabidopsis thaliana has at least three different aldehyde oxidases and one xanthine oxidase. Three different cDNA clones encoding putative aldehyde...... oxidases (AtAO1, 2, 3) were isolated. An aldehyde oxidase is the last step in abscisic acid (ABA) biosynthesis. AtAO1 is mainly expressed in seeds and roots which might reflect that it is involved in ABA biosynthesis....

Arabidopsis CDS blastp result: AK288349 [KOME

Lifescience Database Archive (English)

Full Text Available AK288349 J090023P19 At2g46590.1 68415.m05811 Dof zinc finger protein DAG2 / Dof affecting germination... 2 (DAG2) identical to SP|Q9ZPY0 DOF zinc finger protein DAG2 (Dof affecting germination 2) {Arabidopsis thaliana} 1e-23 ...

Arabidopsis CDS blastp result: AK241364 [KOME

Lifescience Database Archive (English)

Full Text Available AK241364 J065152E11 At2g46590.1 68415.m05811 Dof zinc finger protein DAG2 / Dof affecting germination... 2 (DAG2) identical to SP|Q9ZPY0 DOF zinc finger protein DAG2 (Dof affecting germination 2) {Arabidopsis thaliana} 2e-20 ...

AtMyb7, a subgroup 4 R2R3 Myb, negatively regulates ABA-induced inhibition of seed germination by blocking the expression of the bZIP transcription factor ABI5

KAUST Repository

Kim, Junhyeok; Hyun, Wooyoung; Nguyen, Hoai Nguyen; Jeong, Chanyoung; Xiong, Liming; Hong, Sukwhan; Lee, Hojoung

2014-01-01

Various Myb proteins have been shown to play crucial roles in plants, including primary and secondary metabolism, determination of cell fate and identity, regulation of development and involvement in responses to biotic and abiotic stresses. The 126 R2R3 Myb proteins (with two Myb repeats) have been found in Arabidopsis; however, the functions of most of these proteins remain to be fully elucidated. In the present study, we characterized the function of AtMyb7 using molecular biological and genetic analyses. We used qRT-PCR to determine the levels of stress-response gene transcripts in wild-type and atmyb7 plants. We showed that ArabidopsisAtMyb7 plays a critical role in seed germination. Under abscisic acid (ABA) and high-salt stress conditions, atmyb7 plants showed a lower germination rate than did wild-type plants. Furthermore, AtMyb7 promoter:GUS seeds exhibited different expression patterns in response to variations in the seed imbibition period. AtMyb7 negatively controls the expression of the gene encoding bZIP transcription factor, ABI5, which is a key transcription factor in ABA signalling and serves as a crucial regulator of germination inhibition in Arabidopsis. © 2014 John Wiley & Sons Ltd.

AtMyb7, a subgroup 4 R2R3 Myb, negatively regulates ABA-induced inhibition of seed germination by blocking the expression of the bZIP transcription factor ABI5

KAUST Repository

Kim, Junhyeok

2014-08-27

Various Myb proteins have been shown to play crucial roles in plants, including primary and secondary metabolism, determination of cell fate and identity, regulation of development and involvement in responses to biotic and abiotic stresses. The 126 R2R3 Myb proteins (with two Myb repeats) have been found in Arabidopsis; however, the functions of most of these proteins remain to be fully elucidated. In the present study, we characterized the function of AtMyb7 using molecular biological and genetic analyses. We used qRT-PCR to determine the levels of stress-response gene transcripts in wild-type and atmyb7 plants. We showed that ArabidopsisAtMyb7 plays a critical role in seed germination. Under abscisic acid (ABA) and high-salt stress conditions, atmyb7 plants showed a lower germination rate than did wild-type plants. Furthermore, AtMyb7 promoter:GUS seeds exhibited different expression patterns in response to variations in the seed imbibition period. AtMyb7 negatively controls the expression of the gene encoding bZIP transcription factor, ABI5, which is a key transcription factor in ABA signalling and serves as a crucial regulator of germination inhibition in Arabidopsis. © 2014 John Wiley & Sons Ltd.

A cold-induced pectin methyl-esterase inhibitor gene contributes negatively to freezing tolerance but positively to salt tolerance in Arabidopsis.

Science.gov (United States)

Chen, Jian; Chen, Xuehui; Zhang, Qingfeng; Zhang, Yidan; Ou, Xiangli; An, Lizhe; Feng, Huyuan; Zhao, Zhiguang

2018-03-01

Plant pectin methyl-esterase (PME) and PME inhibitor (PMEI) belong to large gene families whose members are proposed to be widely involved in growth, development, and stress responses; however, the biological functions of most PMEs and PMEIs have not been characterized. In this study, we studied the roles of CbPMEI1, a cold-induced pectin methyl-esterase inhibitor (PMEI) gene from Chorispora bungeana, under freezing and salt stress. The putative CbPMEI1 peptide shares highest similarity (83%) with AT5G62360 (PMEI13) of Arabidopsis. Overexpression of either CbPMEI1 or PMEI13 in Arabidopsis decreased tissue PME activity and enhanced the degree of methoxylation of cell wall pectins, indicating that both genes encode functional PMEIs. CbPMEI1 and PMEI13 were induced by cold but repressed by salt stress and abscisic acid, suggesting distinct roles of the genes in freezing and salt stress tolerance. Interestingly, transgenic Arabidopsis plants overexpressing CbPMEI1 or PMEI13 showed decreased freezing tolerance, as indicated by survival and electrolyte leakage assays. On the other hand, the salt tolerance of transgenic plants was increased, showing higher rates of germination, root growth, and survival under salinity conditions as compared with non-transgenic wild-type plants. Although the transgenic plants were freezing-sensitive, they showed longer roots than wild-type plants under cold conditions, suggesting a role of PMEs in balancing the trade-off between freezing tolerance and growth. Thus, our study indicates that CbPMEI1 and PMEI13 are involved in root growth regulation under cold and salt stresses, and suggests that PMEIs may be potential targets for genetic engineering aimed to improve fitness of plants under stress conditions. Copyright © 2018 Elsevier GmbH. All rights reserved.

SA and ROS are involved in methyl salicylate-induced programmed cell death in Arabidopsis thaliana.

Science.gov (United States)

Yun, Li Juan; Chen, Wen Li

2011-07-01

Programmed cell death (PCD) is a genetically encoded, active process that results in the death of individual cells, tissues, or whole organs, which plays an important role in the life cycles of plants and animals. Previous studies show that methyl salicylate (MeSA) is a defense signal molecular associated with systemic acquired resistance and hypersensitive reaction; however, whether MeSA can induce PCD in plant is still unknown. The morphological changes of Arabidopsis thaliana protoplasts exposed to MeSA were observed under fluorescence microscopy and transmission electron microscopy, and the induction of PCD was clearly distinguished by intense perinuclear chromatin margination, condensation of nuclear chromatin and DNA laddering after 3-h exposure of 100 μM MeSA. Our results also showed that salicylic acid (SA) was involved in MeSA-induced PCD by using a transgenic nahG Arabidopsis thaliana line, and the process was mediated by reactive oxygen species, which functioned with SA by making an amplification loop. Our study showed that MeSA could induce PCD in plant cell for the first time.

Loss of ferulate 5-hydroxylase leads to Mediator-dependent inhibition of soluble phenylpropanoid biosynthesis in Arabidopsis

Energy Technology Data Exchange (ETDEWEB)

Anderson, Nickolas; Bonawitz, Nicholas D.; Nyffeler, Kayleigh E.; Chapple, Clint

2015-06-05

Phenylpropanoids are phenylalanine-derived specialized metabolites and include important structural components of plant cell walls, such as lignin and hydroxycinnamic acids, as well as ultraviolet and visible light-absorbing pigments, such as hydroxycinnamate esters (HCEs) and anthocyanins. Previous work has revealed a remarkable degree of plasticity in HCE biosynthesis, such that most Arabidopsis (Arabidopsis thaliana) mutants with blockages in the pathway simply redirect carbon flux to atypical HCEs. In contrast, the ferulic acid hydroxylase1 (fah1) mutant accumulates greatly reduced levels of HCEs, suggesting that phenylpropanoid biosynthesis may be repressed in response to the loss of FERULATE 5-HYDROXYLASE (F5H) activity. Here, we show that in fah1 mutant plants, the activity of HCE biosynthetic enzymes is not limiting for HCE accumulation, nor is phenylpropanoid flux diverted to the synthesis of cell wall components or flavonol glycosides. We further show that anthocyanin accumulation is also repressed in fah1 mutants and that this repression is specific to tissues in which F5H is normally expressed. Finally, we show that repression of both HCE and anthocyanin biosynthesis in fah1 mutants is dependent on the MED5a/5b subunits of the transcriptional coregulatory complex Mediator, which are similarly required for the repression of lignin biosynthesis and the stunted growth of the phenylpropanoid pathway mutant reduced epidermal fluorescence8. Taken together, these observations show that the synthesis of HCEs and anthocyanins is actively repressed in a MEDIATOR-dependent manner in Arabidopsis fah1 mutants and support an emerging model in which MED5a/5b act as central players in the homeostatic repression of phenylpropanoid metabolism.

Condensin II Alleviates DNA Damage and Is Essential for Tolerance of Boron Overload Stress in Arabidopsis[W

Science.gov (United States)

Sakamoto, Takuya; Inui, Yayoi Tsujimoto; Uraguchi, Shimpei; Yoshizumi, Takeshi; Matsunaga, Sachihiro; Mastui, Minami; Umeda, Masaaki; Fukui, Kiichi; Fujiwara, Toru

2011-01-01

Although excess boron (B) is known to negatively affect plant growth, its molecular mechanism of toxicity is unknown. We previously isolated two Arabidopsis thaliana mutants, hypersensitive to excess B (heb1-1 and heb2-1). In this study, we found that HEB1 and HEB2 encode the CAP-G2 and CAP-H2 subunits, respectively, of the condensin II protein complex, which functions in the maintenance of chromosome structure. Growth of Arabidopsis seedlings in medium containing excess B induced expression of condensin II subunit genes. Simultaneous treatment with zeocin, which induces DNA double-strand breaks (DSBs), and aphidicolin, which blocks DNA replication, mimicked the effect of excess B on root growth in the heb mutants. Both excess B and the heb mutations upregulated DSBs and DSB-inducible gene transcription, suggesting that DSBs are a cause of B toxicity and that condensin II reduces the incidence of DSBs. The Arabidopsis T-DNA insertion mutant atr-2, which is sensitive to replication-blocking reagents, was also sensitive to excess B. Taken together, these data suggest that the B toxicity mechanism in plants involves DSBs and possibly replication blocks and that plant condensin II plays a role in DNA damage repair or in protecting the genome from certain genotoxic stressors, particularly excess B. PMID:21917552

Arabidopsis CDS blastp result: AK121264 [KOME

Lifescience Database Archive (English)

Full Text Available AK121264 J023105D06 At3g15730.1 phospholipase D alpha 1 / PLD alpha 1 (PLDALPHA1) (PLD1) / choli...ne phosphatase 1 identical to SP:Q38882 Phospholipase D alpha 1 (EC 3.1.4.4) (AtPLDalpha1) (PLD alpha 1) (Choli...ne phosphatase 1) (Phosphatidylcholine-hydrolyzing phospholipase D 1) (PLDalpha) [Arabidopsis thaliana] 0.0 ...

Etude par génétique inverse du gène codant la protéine TARGET OF RAPAMYCIN d'Arabidopsis thaliana (AtTOR), l'homologue d'une kinase contrôlant la croissance cellulaire chez les eucaryotes

OpenAIRE

Menand, Benoit

2002-01-01

TOR (target of rapamycin) protein kinases were identified in yeast, mammals and Drosophila as central controllers of cell growth. Thu, G1 to S phases progression through the cell cycle is blocked by rapamycin, a drug which specifically inhibits TOR activity by forming a ternary complex with the peptidyl-prolyl isomerase FKBP12 (FK506 and rapamycin binding protein), and the FKBP-rapamycin binding domain (FRB) of TOR proteins. This work presents the study, the Arabidopsis homologue of yeast and...

Computational analyses and annotations of the Arabidopsis peroxidasegene family

DEFF Research Database (Denmark)

Østergaard, Lars; Pedersen, Anders Gorm; Jespersen, Hans M.

1998-01-01

Classical heme-containing plant peroxidases have been ascribed a wide variety of functional roles related to development, defense, lignification and hormonal signaling. More than 40 peroxidase genes are now known in Arabidopsis thaliana for which functional association is complicated by a general...... containing 40-71% adenine, a rare feature observed also in cDNAs which predominantly encode stress-induced proteins, and which may indicate translational regulation....

Impacts of high ATP supply from chloroplasts and mitochondria on the leaf metabolism of Arabidopsis thaliana

Directory of Open Access Journals (Sweden)

Chao eLiang

2015-10-01

Full Text Available Chloroplasts and mitochondria are the major ATP producing organelles in plant leaves. Arabidopsis thaliana purple acid phosphatase 2 (AtPAP2 is a phosphatase dually targeted to the outer membranes of both organelles and it plays a role in the import of selected nuclear-encoded proteins into these two organelles. Overexpression (OE of AtPAP2 in Arabidopsis thaliana accelerates plant growth and promotes flowering, seed yield and biomass at maturity. Measurement of ADP/ATP/NADP+/NADPH contents in the leaves of 20-day-old OE and wild-type lines at the end of night and at 1 and 8 h following illumination in a 16/8 h photoperiod revealed that the ATP levels and ATP/NADPH ratios were significantly increased in the OE line at all three time points. The AtPAP2 OE line is therefore a good model to investigate the impact of high energy on the global molecular status of Arabidopsis. In this study, transcriptome, proteome and metabolome profiles of the high ATP transgenic line were examined and compared with those of wild-type plants. A comparison of OE and WT at the end of the night provide valuable information on the impact of higher ATP output from mitochondria on plant physiology, as mitochondrial respiration is the major source of ATP in the dark in leaves. Similarly, comparison of OE and WT following illumination will provide information on the impact of higher energy output from chloroplasts on plant physiology. Overexpression of AtPAP2 was found to significantly affect the transcript and protein abundances of genes encoded by the two organellar genomes. For example, the protein abundances of many ribosomal proteins encoded by the chloroplast genome were higher in the AtPAP2 OE line under both light and dark conditions, while the protein abundances of multiple components of the photosynthetic complexes were lower. RNA-seq data also showed that the transcription of the mitochondrial genome is greatly affected by the availability of energy. These data

The genetic basis of constitutive and herbivore-induced ESP-independent nitrile formation in Arabidopsis.

Science.gov (United States)

Burow, Meike; Losansky, Anja; Müller, René; Plock, Antje; Kliebenstein, Daniel J; Wittstock, Ute

2009-01-01

Glucosinolates are a group of thioglucosides that are components of an activated chemical defense found in the Brassicales. Plant tissue damage results in hydrolysis of glucosinolates by endogenous thioglucosidases known as myrosinases. Spontaneous rearrangement of the aglucone yields reactive isothiocyanates that are toxic to many organisms. In the presence of specifier proteins, alternative products, namely epithionitriles, simple nitriles, and thiocyanates with different biological activities, are formed at the expense of isothiocyanates. Recently, simple nitriles were recognized to serve distinct functions in plant-insect interactions. Here, we show that simple nitrile formation in Arabidopsis (Arabidopsis thaliana) ecotype Columbia-0 rosette leaves increases in response to herbivory and that this increase is independent of the known epithiospecifier protein (ESP). We combined phylogenetic analysis, a screen of Arabidopsis mutants, recombinant protein characterization, and expression quantitative trait locus mapping to identify a gene encoding a nitrile-specifier protein (NSP) responsible for constitutive and herbivore-induced simple nitrile formation in Columbia-0 rosette leaves. AtNSP1 is one of five Arabidopsis ESP homologues that promote simple nitrile, but not epithionitrile or thiocyanate, formation. Four of these homologues possess one or two lectin-like jacalin domains, which share a common ancestry with the jacalin domains of the putative Arabidopsis myrosinase-binding proteins MBP1 and MBP2. A sixth ESP homologue lacked specifier activity and likely represents the ancestor of the gene family with a different biochemical function. By illuminating the genetic and biochemical bases of simple nitrile formation, our study provides new insights into the evolution of metabolic diversity in a complex plant defense system.

Arabidopsis mitochondrial protein slow embryo development1 is essential for embryo development

International Nuclear Information System (INIS)

Ju, Yan; Liu, Chunying; Lu, Wenwen; Zhang, Quan; Sodmergen

2016-01-01

The plant seeds formation are crucial parts in reproductive process in seed plants as well as food source for humans. Proper embryo development ensure viable seed formation. Here, we showed an Arabidopsis T-DNA insertion mutant slow embryo development1 (sed1) which exhibited retarded embryogenesis, led to aborted seeds. Embryo without SED1 developed slower compared to normal one and could be recognized at early globular stage by its white appearance. In later development stage, storage accumulated poorly with less protein and lipid body production. In vitro culture did not rescue albino embryo. SED1 encoded a protein targeted to mitochondria. Transmission electron microscopic analysis revealed that mitochondria developed abnormally, and more strikingly plastid failed to construct grana in time in sed1/sed1 embryo. These data indicated that SED1 is indispensable for embryogenesis in Arabidopsis, and the mitochondria may be involved in the regulation of many aspects of seed development. -- Highlights: •Arabidopsis SED1 is essential for embryo development. •The sed1 embryo accumulates less storage and has abnormal ultrastructure. •SED1 localizes to the mitochondrion.

Arabidopsis mitochondrial protein slow embryo development1 is essential for embryo development

Energy Technology Data Exchange (ETDEWEB)

Ju, Yan; Liu, Chunying; Lu, Wenwen; Zhang, Quan; Sodmergen, E-mail: sodmergn@pku.edu.cn

2016-05-27

The plant seeds formation are crucial parts in reproductive process in seed plants as well as food source for humans. Proper embryo development ensure viable seed formation. Here, we showed an Arabidopsis T-DNA insertion mutant slow embryo development1 (sed1) which exhibited retarded embryogenesis, led to aborted seeds. Embryo without SED1 developed slower compared to normal one and could be recognized at early globular stage by its white appearance. In later development stage, storage accumulated poorly with less protein and lipid body production. In vitro culture did not rescue albino embryo. SED1 encoded a protein targeted to mitochondria. Transmission electron microscopic analysis revealed that mitochondria developed abnormally, and more strikingly plastid failed to construct grana in time in sed1/sed1 embryo. These data indicated that SED1 is indispensable for embryogenesis in Arabidopsis, and the mitochondria may be involved in the regulation of many aspects of seed development. -- Highlights: •Arabidopsis SED1 is essential for embryo development. •The sed1 embryo accumulates less storage and has abnormal ultrastructure. •SED1 localizes to the mitochondrion.

Cellulose synthesis genes CESA6 and CSI1 are important for salt stress tolerance in Arabidopsis.

Science.gov (United States)

Zhang, Shuang-Shuang; Sun, Le; Dong, Xinran; Lu, Sun-Jie; Tian, Weidong; Liu, Jian-Xiang

2016-07-01

Two salt hypersensitive mutants she1 and she2 were identified through genetic screening. SHE1 encodes a cellulose synthase CESA6 while SHE2 encodes a cellulose synthase-interactive protein CSI1. Both of them are involved in cellulose deposition. Our results demonstrated that the sustained cellulose synthesis is important for salt stress tolerance in Arabidopsis. © 2015 Institute of Botany, Chinese Academy of Sciences.

Expression of transcription factors after short-term exposure of Arabidopsis thaliana cell cultures to hyper-g, and to simulated and sounding rocket micro-g

Science.gov (United States)

Hampp, R.; Babbick, M.

Previous microarray studies with cell cultures of Arabidopsis thaliana cv Columbia have shown responses in gene expression which were partly specific to exposure to microgravity sounding rocket experiment TEXUS In order to get access to early responses upon changes in gravitational fields we used exposure times as short as 2 min For this purpose we selected a range of genes which code for different groups of transcription factors WRKY ERF MYB MADS Samples were taken in 5-min clinorotation 2- and 3-dimensional hypergravity 8g and 2-min intervals sounding rocket experiment Amounts of transcripts were determined by quantitative RT PCR Most transcripts showed a significant transient change in content within a time frame of up to 30 min after changing the external gravitational field strength They could be grouped into 1 basic stress responses which occurred under all conditions 2 clinorotation-related effects which were either identical or opposite between 2D 60 rpm 4x10 -2 g and 3D clinorotation random positioning machine and 3 alterations specific to the microgravity exposure under sounding rocket conditions MAXUS The data are discussed in relation to gravitation-dependent signalling chains and with regard to the simulation of microgravity by means of clinorotation Supported by a grant from the Deutsches Zentrum f u r Luft- und Raumfahrt e V grant no 50 WB 0143

The Arabidopsis splicing factors, AtU2AF65, AtU2AF35, and AtSF1 shuttle between nuclei and cytoplasms

KAUST Repository

Park, Hyo-Young

2017-04-21

The Arabidopsis splicing factors, AtU2AF65, AtU2AF35, and AtSF1 shuttle between nuclei and cytoplasms. These proteins also move rapidly and continuously in the nuclei, and their movements are affected by ATP depletion. The U2AF65 proteins are splicing factors that interact with SF1 and U2AF35 proteins to promote U2snRNP for the recognition of the pre-mRNA 3\\' splice site during early spliceosome assembly. We have determined the subcellular localization and movement of these proteins\\' Arabidopsis homologs. It was found that Arabidopsis U2AF65 homologs, AtU2AF65a, and AtU2AF65b proteins interact with AtU2AF35a and AtU2AF35b, which are Arabidopsis U2AF35 homologs. We have examined the mobility of these proteins including AtSF1 using fluorescence recovery after photobleaching and fluorescence loss in photobleaching analyses. These proteins displayed dynamic movements in nuclei and their movements were affected by ATP depletion. We have also demonstrated that these proteins shuttle between nuclei and cytoplasms, suggesting that they may also function in cytoplasm. These results indicate that such splicing factors show very similar characteristics to their human counterparts, suggesting evolutionary conservation.

The Arabidopsis splicing factors, AtU2AF65, AtU2AF35, and AtSF1 shuttle between nuclei and cytoplasms

KAUST Repository

Park, Hyo-Young; Lee, Keh Chien; Jang, Yun Hee; Kim, SoonKap; Thu, May Phyo; Lee, Jeong Hwan; Kim, Jeong-Kook

2017-01-01

The Arabidopsis splicing factors, AtU2AF65, AtU2AF35, and AtSF1 shuttle between nuclei and cytoplasms. These proteins also move rapidly and continuously in the nuclei, and their movements are affected by ATP depletion. The U2AF65 proteins are splicing factors that interact with SF1 and U2AF35 proteins to promote U2snRNP for the recognition of the pre-mRNA 3' splice site during early spliceosome assembly. We have determined the subcellular localization and movement of these proteins' Arabidopsis homologs. It was found that Arabidopsis U2AF65 homologs, AtU2AF65a, and AtU2AF65b proteins interact with AtU2AF35a and AtU2AF35b, which are Arabidopsis U2AF35 homologs. We have examined the mobility of these proteins including AtSF1 using fluorescence recovery after photobleaching and fluorescence loss in photobleaching analyses. These proteins displayed dynamic movements in nuclei and their movements were affected by ATP depletion. We have also demonstrated that these proteins shuttle between nuclei and cytoplasms, suggesting that they may also function in cytoplasm. These results indicate that such splicing factors show very similar characteristics to their human counterparts, suggesting evolutionary conservation.

Phylogenetic analysis of fungal heterotrimeric G protein-encoding genes and their expression during dimorphism in Mucor circinelloides.

Science.gov (United States)

Valle-Maldonado, Marco Iván; Jácome-Galarza, Irvin Eduardo; Díaz-Pérez, Alma Laura; Martínez-Cadena, Guadalupe; Campos-García, Jesús; Ramírez-Díaz, Martha Isela; Reyes-De la Cruz, Homero; Riveros-Rosas, Héctor; Díaz-Pérez, César; Meza-Carmen, Víctor

2015-12-01

In fungi, heterotrimeric G proteins are key regulators of biological processes such as mating, virulence, morphology, among others. Mucor circinelloides is a model organism for many biological processes, and its genome contains the largest known repertoire of genes that encode putative heterotrimeric G protein subunits in the fungal kingdom: twelve Gα (McGpa1-12), three Gβ (McGpb1-3), and three Gγ (McGpg1-3). Phylogenetic analysis of fungal Gα showed that they are divided into four distinct groups as reported previously. Fungal Gβ and Gγ are also divided into four phylogenetic groups, and to our understanding this is the first report of a phylogenetic classification for fungal Gβ and Gγ subunits. Almost all genes that encode putative heterotrimeric G subunits in M. circinelloides are differentially expressed during dimorphic growth, except for McGpg1 (Gγ) that showed very low mRNA levels at all developmental stages. Moreover, several of the subunits are expressed in a similar pattern and at the same level, suggesting that they constitute discrete complexes. For example, McGpb3 (Gβ), and McGpg2 (Gγ), are co-expressed during mycelium growth, and McGpa1, McGpb2, and McGpg2, are co-expressed during yeast development. These findings provide the conceptual framework to study the biological role of these genes during M. circinelloides morphogenesis. Copyright © 2015 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Biochemical quantitation of the eIF5A hypusination in Arabidopsis thaliana uncovers ABA-dependent regulation

Science.gov (United States)

Belda-Palazón, Borja; Nohales, María A.; Rambla, José L.; Aceña, José L.; Delgado, Oscar; Fustero, Santos; Martínez, M. Carmen; Granell, Antonio; Carbonell, Juan; Ferrando, Alejandro

2014-01-01

The eukaryotic translation elongation factor eIF5A is the only protein known to contain the unusual amino acid hypusine which is essential for its biological activity. This post-translational modification is achieved by the sequential action of the enzymes deoxyhypusine synthase (DHS) and deoxyhypusine hydroxylase (DOHH). The crucial molecular function of eIF5A during translation has been recently elucidated in yeast and it is expected to be fully conserved in every eukaryotic cell, however the functional description of this pathway in plants is still sparse. The genetic approaches with transgenic plants for either eIF5A overexpression or antisense have revealed some activities related to the control of cell death processes but the molecular details remain to be characterized. One important aspect of fully understanding this pathway is the biochemical description of the hypusine modification system. Here we have used recombinant eIF5A proteins either modified by hypusination or non-modified to establish a bi-dimensional electrophoresis (2D-E) profile for the three eIF5A protein isoforms and their hypusinated or unmodified proteoforms present in Arabidopsis thaliana. The combined use of the recombinant 2D-E profile together with 2D-E/western blot analysis from whole plant extracts has provided a quantitative approach to measure the hypusination status of eIF5A. We have used this information to demonstrate that treatment with the hormone abscisic acid produces an alteration of the hypusine modification system in Arabidopsis thaliana. Overall this study presents the first biochemical description of the post-translational modification of eIF5A by hypusination which will be functionally relevant for future studies related to the characterization of this pathway in Arabidopsis thaliana. PMID:24904603

The Arabidopsis CROWDED NUCLEI genes regulate seed germination by modulating degradation of ABI5 protein.

Science.gov (United States)

Zhao, Wenming; Guan, Chunmei; Feng, Jian; Liang, Yan; Zhan, Ni; Zuo, Jianru; Ren, Bo

2016-07-01

In Arabidopsis, the phytohormone abscisic acid (ABA) plays a vital role in inhibiting seed germination and in post-germination seedling establishment. In the ABA signaling pathway, ABI5, a basic Leu zipper transcription factor, has important functions in the regulation of seed germination. ABI5 protein localizes in nuclear bodies, along with AFP, COP1, and SIZ1, and was degraded through the 26S proteasome pathway. However, the mechanisms of ABI5 nuclear body formation and ABI5 protein degradation remain obscure. In this study, we found that the Arabidopsis CROWDED NUCLEI (CRWN) proteins, predicted nuclear matrix proteins essential for maintenance of nuclear morphology, also participate in ABA-controlled seed germination by regulating the degradation of ABI5 protein. During seed germination, the crwn mutants are hypersensitive to ABA and have higher levels of ABI5 protein compared to wild type. Genetic analysis suggested that CRWNs act upstream of ABI5. The observation that CRWN3 colocalizes with ABI5 in nuclear bodies indicates that CRWNs might participate in ABI5 protein degradation in nuclear bodies. Moreover, we revealed that the extreme C-terminal of CRWN3 protein is necessary for its function in the response to ABA in germination. Our results suggested important roles of CRWNs in ABI5 nuclear body organization and ABI5 protein degradation during seed germination. © 2015 Institute of Botany, Chinese Academy of Sciences.

Over-expression of Arabidopsis thaliana SFD1/GLY1, the gene encoding plastid localized glycerol-3-phosphate dehydrogenase, increases plastidic lipid content in transgenic rice plants.

Science.gov (United States)

Singh, Vijayata; Singh, Praveen Kumar; Siddiqui, Adnan; Singh, Subaran; Banday, Zeeshan Zahoor; Nandi, Ashis Kumar

2016-03-01

Lipids are the major constituents of all membranous structures in plants. Plants possess two pathways for lipid biosynthesis: the prokaryotic pathway (i.e., plastidic pathway) and the eukaryotic pathway (i.e., endoplasmic-reticulum (ER) pathway). Whereas some plants synthesize galactolipids from diacylglycerol assembled in the plastid, others, including rice, derive their galactolipids from diacylglycerols assembled by the eukaryotic pathway. Arabidopsis thaliana glycerol-3-phosphate dehydrogenase (G3pDH), coded by SUPPRESSOR OF FATTY ACID DESATURASE 1 (SFD1; alias GLY1) gene, catalyzes the formation of glycerol 3-phosphate (G3p), the backbone of many membrane lipids. Here SFD1 was introduced to rice as a transgene. Arabidopsis SFD1 localizes in rice plastids and its over-expression increases plastidic membrane lipid content in transgenic rice plants without any major impact on ER lipids. The results suggest that over-expression of plastidic G3pDH enhances biosynthesis of plastid-localized lipids in rice. Lipid composition in the transgenic plants is consistent with increased phosphatidylglycerol synthesis in the plastid and increased galactolipid synthesis from diacylglycerol produced via the ER pathway. The transgenic plants show a higher photosynthetic assimilation rate, suggesting a possible application of this finding in crop improvement.

Characterization and functional analysis of four HYH splicing variants in Arabidopsis hypocotyl elongation.

Science.gov (United States)

Li, Chen; Zheng, Lanlan; Zhang, Jingxuan; Lv, Yanxia; Liu, Jianping; Wang, Xuanbin; Palfalvi, Gergo; Wang, Guodong; Zhang, Yonghong

2017-07-01

Arabidopsis thaliana LONG HYPOCOTYL5 (HY5) is a positive regulator of the light signaling pathway. The hy5 mutant has an elongated hypocotyl in all light conditions, whereas the hy5 homolog (hyh) mutant has a very weak phenotype, but only in blue light. However, overexpression of HYH rescues the elongated hypocotyl phenotype in the hy5 null mutant. Here, we report the identification of four HYH splicing variants in Arabidopsis. Alternative splicing in the 5' region of the HYH gene occurred such that the proteins encoded by all four HYH variants retained their bZIP domain. In hypocotyl tissue, transcript levels of HYH.2, HYH.3, and HYH.4 were higher than those of HYH.1. Like HY5, all HYH variants were induced by light. Functional analysis of the four HYH variants, based on their abilities to complement the hy5 mutant, indicated that they have similar roles in hypocotyl development, and may function redundantly with HY5. Our results indicate that the bZIP domain in HYH is critical for the function of four variants in the compensation of hy5 mutant in hypocotyl development. Additionally, while HY5/HYH is found in plant species ranging from green algae to flowering plants, the potential alternative splicing events are distinct in different species, with certain HYH variants found with greater frequency in some species than others. Copyright © 2017. Published by Elsevier B.V.

Identification and molecular properties of SUMO-binding proteins in arabidopsis

KAUST Repository

Park, Hyeongcheol

2011-05-20

Reversible conjugation of the small ubiquitin modifier (SUMO) peptide to proteins (SUMOylation) plays important roles in cellular processes in animals and yeasts. However, little is known about plant SUMO targets. To identify SUMO substrates in Arabidopsis and to probe for biological functions of SUMO proteins, we constructed 6xHis-3xFLAG fused AtSUMO1 (HFAtSUMO1) controlled by the CaMV35S promoter for transformation into Arabidopsis Col-0. After heat treatment, an increased sumoylation pattern was detected in the transgenic plants. SUMO1-modified proteins were selected after two-dimensional gel electrophoresis (2-DE) image analysis and identified using matrix-assisted laser-desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). We identified 27 proteins involved in a variety of processes such as nucleic acid metabolism, signaling, metabolism, and including proteins of unknown functions. Binding and sumoylation patterns were confirmed independently. Surprisingly, MCM3 (At5G46280), a DNA replication licensing factor, only interacted with and became sumoylated by AtSUMO1, but not by SUMO1ΔGG or AtSUMO3. The results suggest specific interactions between sumoylation targets and particular sumoylation enzymes. ©2011 KSMCB.

Opposite roles of the Arabidopsis cytokinin receptors AHK2 and AHK3 in the expression of plastid genes and genes for the plastid transcriptional machinery during senescence.

Science.gov (United States)

Danilova, Maria N; Kudryakova, Natalia V; Doroshenko, Anastasia S; Zabrodin, Dmitry A; Rakhmankulova, Zulfira F; Oelmüller, Ralf; Kusnetsov, Victor V

2017-03-01

Cytokinin membrane receptors of the Arabidopsis thaliana AHK2 and AHK3 play opposite roles in the expression of plastid genes and genes for the plastid transcriptional machinery during leaf senescence Loss-of-function mutants of Arabidopsis thaliana were used to study the role of cytokinin receptors in the expression of chloroplast genes during leaf senescence. Accumulation of transcripts of several plastid-encoded genes is dependent on the АНК2/АНК3 receptor combination. АНК2 is particularly important at the final stage of plant development and, unlike АНК3, a positive regulator of leaf senescence. Cytokinin-dependent up-regulation of the nuclear encoded genes for chloroplast RNA polymerases RPOTp and RPOTmp suggests that the hormone controls plastid gene expression, at least in part, via the expression of nuclear genes for the plastid transcription machinery. This is further supported by cytokinin dependent regulation of genes for the nuclear encoded plastid σ-factors, SIG1-6, which code for components of the transcriptional apparatus in chloroplasts.

Selective cytotoxicity of PAMAM G5 core–PAMAM G2.5 shell tecto-dendrimers on melanoma cells

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Schilrreff P

2012-07-01

fashion in comparison to their building blocks and to its closest counterpart, PAMAM G6.5. After being actively taken up by epithelial cells, G5G2.5 caused cytotoxicity only on SK-Mel-28 cells, including depletion of intracellular glutathione and fast necrosis that was manifested above 5 µM G5G2.5. It cannot be discounted that traces of LiCl within G5G2.5 were involved in such deleterious effects.Conclusion: These preliminary results suggest that at concentrations that do not damage healthy keratinocytes, G5G2.5 could display antimelanoma activity.Keywords: core–shell tecto-dendrimers, SK-Mel-28 cells, oxidative stress

Sequence and RT-PCR expression analysis of two peroxidases from Arabidopsis thaliana belonging to a novel evolutionary branch of plant peroxidases.

Science.gov (United States)

Kjaersgård, I V; Jespersen, H M; Rasmussen, S K; Welinder, K G

1997-03-01

cDNA clones encoding two new Arabidopsis thaliana peroxidases, ATP 1a and ATP 2a, have been identified by searching the Arabidopsis database of expressed sequence tags (dbEST). They represent a novel branch of hitherto uncharacterized plant peroxidases which is only 35% identical in amino acid sequence to the well characterized group of basic plant peroxidases represented by the horseradish (Armoracia rusticana) isoperoxidases HRP C, HRP E5 and the similar Arabidopsis isoperoxidases ATP Ca, ATP Cb, and ATP Ea. However ATP 1a is 87% identical in amino acid sequence to a peroxidase encoded by an mRNA isolated from cotton (Gossypium hirsutum). As cotton and Arabidopsis belong to rather diverse families (Malvaceae and Crucifereae, respectively), in contrast with Arabidopsis and horseradish (both Crucifereae), the high degree of sequence identity indicates that this novel type of peroxidase, albeit of unknown function, is likely to be widespread in plant species. The atp 1 and atp 2 types of cDNA sequences were the most redundant among the 28 different isoperoxidases identified among about 200 peroxidase encoding ESTs. Interestingly, 8 out of totally 38 EST sequences coding for ATP 1 showed three identical nucleotide substitutions. This variant form is designated ATP 1b. Similarly, six out of totally 16 EST sequences coding for ATP 2 showed a number of deletions and nucleotide changes. This variant form is designated ATP 2b. The selected EST clones are full-length and contain coding regions of 993 nucleotides for atp 1a, and 984 nucleotides for atp 2a. These regions show 61% DNA sequence identity. The predicted mature proteins ATP 1a, and ATP 2a are 57% identical in sequence and contain the structurally and functionally important residues, characteristic of the plant peroxidase superfamily. However, they do show two differences of importance to peroxidase catalysis: (1) the asparagine residue linked with the active site distal histidine via hydrogen bonding is absent

Characterization and subcellular compartmentation of recombinant 4-hydroxyphenylpyruvate dioxygenase from Arabidopsis in transgenic tobacco.

Science.gov (United States)

Garcia, I; Rodgers, M; Pepin, R; Hsieh, T F; Matringe, M

1999-04-01

4-Hydroxyphenylpyruvate dioxygenase (4HPPD) catalyzes the formation of homogentisate (2,5-dihydroxyphenylacetate) from p-hydroxyphenylpyruvate and molecular oxygen. In plants this enzyme activity is involved in two distinct metabolic processes, the biosynthesis of prenylquinones and the catabolism of tyrosine. We report here the molecular and biochemical characterization of an Arabidopsis 4HPPD and the compartmentation of the recombinant protein in chlorophyllous tissues. We isolated a 1508-bp cDNA with one large open reading frame of 1338 bp. Southern analysis strongly suggested that this Arabidopsis 4HPPD is encoded by a single-copy gene. We investigated the biochemical characteristics of this 4HPPD by overproducing the recombinant protein in Escherichia coli JM105. The subcellular localization of the recombinant 4HPPD in chlorophyllous tissues was examined by overexpressing its complete coding sequence in transgenic tobacco (Nicotiana tabacum), using Agrobacterium tumefaciens transformation. We performed western analyses for the immunodetection of protein extracts from purified chloroplasts and total leaf extracts and for the immunocytochemistry on tissue sections. These analyses clearly revealed that 4HPPD was confined to the cytosol compartment, not targeted to the chloroplast. Western analyses confirmed the presence of a cytosolic form of 4HPPD in cultured green Arabidopsis cells.

The maize glossy13 gene, cloned via BSR-Seq and Seq-walking encodes a putative ABC transporter required for the normal accumulation of epicuticular waxes.

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Li Li

Full Text Available Aerial plant surfaces are covered by epicuticular waxes that among other purposes serve to control water loss. Maize glossy mutants originally identified by their "glossy" phenotypes exhibit alterations in the accumulation of epicuticular waxes. By combining data from a BSR-Seq experiment and the newly developed Seq-Walking technology, GRMZM2G118243 was identified as a strong candidate for being the glossy13 gene. The finding that multiple EMS-induced alleles contain premature stop codons in GRMZM2G118243, and the one knockout allele of gl13, validates the hypothesis that gene GRMZM2G118243 is gl13. Consistent with this, GRMZM2G118243 is an ortholog of AtABCG32 (Arabidopsis thaliana, HvABCG31 (barley and OsABCG31 (rice, which encode ABCG subfamily transporters involved in the trans-membrane transport of various secondary metabolites. We therefore hypothesize that gl13 is involved in the transport of epicuticular waxes onto the surfaces of seedling leaves.

Abscisic Acid–Responsive Guard Cell Metabolomes of Arabidopsis Wild-Type and gpa1 G-Protein Mutants[C][W

Science.gov (United States)

Jin, Xiaofen; Wang, Rui-Sheng; Zhu, Mengmeng; Jeon, Byeong Wook; Albert, Reka; Chen, Sixue; Assmann, Sarah M.

2013-01-01

Individual metabolites have been implicated in abscisic acid (ABA) signaling in guard cells, but a metabolite profile of this specialized cell type is lacking. We used liquid chromatography–multiple reaction monitoring mass spectrometry for targeted analysis of 85 signaling-related metabolites in Arabidopsis thaliana guard cell protoplasts over a time course of ABA treatment. The analysis utilized ∼350 million guard cell protoplasts from ∼30,000 plants of the Arabidopsis Columbia accession (Col) wild type and the heterotrimeric G-protein α subunit mutant, gpa1, which has ABA-hyposensitive stomata. These metabolomes revealed coordinated regulation of signaling metabolites in unrelated biochemical pathways. Metabolites clustered into different temporal modules in Col versus gpa1, with fewer metabolites showing ABA-altered profiles in gpa1. Ca2+-mobilizing agents sphingosine-1-phosphate and cyclic adenosine diphosphate ribose exhibited weaker ABA-stimulated increases in gpa1. Hormone metabolites were responsive to ABA, with generally greater responsiveness in Col than in gpa1. Most hormones also showed different ABA responses in guard cell versus mesophyll cell metabolomes. These findings suggest that ABA functions upstream to regulate other hormones, and are also consistent with G proteins modulating multiple hormonal signaling pathways. In particular, indole-3-acetic acid levels declined after ABA treatment in Col but not gpa1 guard cells. Consistent with this observation, the auxin antagonist α-(phenyl ethyl-2-one)-indole-3-acetic acid enhanced ABA-regulated stomatal movement and restored partial ABA sensitivity to gpa1. PMID:24368793

Arabidopsis brassinosteroid biosynthetic mutant dwarf7-1 exhibits slower rates of cell division and shoot induction

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Schulz Burkhard

2010-12-01

Full Text Available Abstract Background Plant growth depends on both cell division and cell expansion. Plant hormones, including brassinosteroids (BRs, are central to the control of these two cellular processes. Despite clear evidence that BRs regulate cell elongation, their roles in cell division have remained elusive. Results Here, we report results emphasizing the importance of BRs in cell division. An Arabidopsis BR biosynthetic mutant, dwarf7-1, displayed various characteristics attributable to slower cell division rates. We found that the DWARF4 gene which encodes for an enzyme catalyzing a rate-determining step in the BR biosynthetic pathways, is highly expressed in the actively dividing callus, suggesting that BR biosynthesis is necessary for dividing cells. Furthermore, dwf7-1 showed noticeably slower rates of callus growth and shoot induction relative to wild-type control. Flow cytometric analyses of the nuclei derived from either calli or intact roots revealed that the cell division index, which was represented as the ratio of cells at the G2/M vs. G1 phases, was smaller in dwf7-1 plants. Finally, we found that the expression levels of the genes involved in cell division and shoot induction, such as PROLIFERATING CELL NUCLEAR ANTIGEN2 (PCNA2 and ENHANCER OF SHOOT REGENERATION2 (ESR2, were also lower in dwf7-1 as compared with wild type. Conclusions Taken together, results of callus induction, shoot regeneration, flow cytometry, and semi-quantitative RT-PCR analysis suggest that BRs play important roles in both cell division and cell differentiation in Arabidopsis.

Atypical DNA methylation of genes encoding cysteine-rich peptides in Arabidopsis thaliana

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You Wanhui

2012-04-01

Full Text Available Abstract Background In plants, transposons and non-protein-coding repeats are epigenetically silenced by CG and non-CG methylation. This pattern of methylation is mediated in part by small RNAs and two specialized RNA polymerases, termed Pol IV and Pol V, in a process called RNA-directed DNA methylation. By contrast, many protein-coding genes transcribed by Pol II contain in their gene bodies exclusively CG methylation that is independent of small RNAs and Pol IV/Pol V activities. It is unclear how the different methylation machineries distinguish between transposons and genes. Here we report on a group of atypical genes that display in their coding region a transposon-like methylation pattern, which is associated with gene silencing in sporophytic tissues. Results We performed a methylation-sensitive amplification polymorphism analysis to search for targets of RNA-directed DNA methylation in Arabidopsis thaliana and identified several members of a gene family encoding cysteine-rich peptides (CRPs. In leaves, the CRP genes are silent and their coding regions contain dense, transposon-like methylation in CG, CHG and CHH contexts, which depends partly on the Pol IV/Pol V pathway and small RNAs. Methylation in the coding region is reduced, however, in the synergid cells of the female gametophyte, where the CRP genes are specifically expressed. Further demonstrating that expressed CRP genes lack gene body methylation, a CRP4-GFP fusion gene under the control of the constitutive 35 S promoter remains unmethylated in leaves and is transcribed to produce a translatable mRNA. By contrast, a CRP4-GFP fusion gene under the control of a CRP4 promoter fragment acquires CG and non-CG methylation in the CRP coding region in leaves similar to the silent endogenous CRP4 gene. Conclusions Unlike CG methylation in gene bodies, which does not dramatically affect Pol II transcription, combined CG and non-CG methylation in CRP coding regions is likely to

Cloning of the cryptochrome-encoding PeCRY1 gene from Populus euphratica and functional analysis in Arabidopsis.

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Ke Mao

Full Text Available Cryptochromes are photolyase-like blue/UV-A light receptors that evolved from photolyases. In plants, cryptochromes regulate various aspects of plant growth and development. Despite of their involvement in the control of important plant traits, however, most studies on cryptochromes have focused on lower plants and herbaceous crops, and no data on cryptochrome function are available for forest trees. In this study, we isolated a cryptochrome gene, PeCRY1, from Euphrates poplar (Populus euphratica, and analyzed its structure and function in detail. The deduced PeCRY1 amino acid sequence contained a conserved N-terminal photolyase-homologous region (PHR domain as well as a C-terminal DQXVP-acidic-STAES (DAS domain. Secondary and tertiary structure analysis showed that PeCRY1 shares high similarity with AtCRY1 from Arabidopsis thaliana. PeCRY1 expression was upregulated at the mRNA level by light. Using heterologous expression in Arabidopsis, we showed that PeCRY1 overexpression rescued the cry1 mutant phenotype. In addition, PeCRY1 overexpression inhibited hypocotyl elongation, promoted root growth, and enhanced anthocyanin accumulation in wild-type background seedlings grown under blue light. Furthermore, we examined the interaction between PeCRY1 and AtCOP1 using a bimolecular fluorescence complementation (BiFc assay. Our data provide evidence for the involvement of PeCRY1 in the control of photomorphogenesis in poplar.

Mutational effects of γ-rays and carbon ion beams on Arabidopsis seedlings

International Nuclear Information System (INIS)

Yoshihara, Ryohei; Nozawa, Shigeki; Hase, Yoshihiro; Sakamoto, Ayako N.; Narumi, Issay; Hidema, Jun

2013-01-01

To assess the mutational effects of radiation on vigorously proliferating plant tissue, the mutation spectrum was analyzed with Arabidopsis seedlings using the plasmid-rescue method. Transgenic plants containing the Escherichia coli rpsL gene were irradiated with γ-rays and carbon ion beams (320-MeV 12 C 6+ ), and mutations in the rpsL gene were analyzed. Mutant frequency increased significantly following irradiation by γ-rays, but not by 320-MeV 12 C 6+ . Mutation spectra showed that both radiations increased the frequency of frameshifts and other mutations, including deletions and insertions, but only γ-rays increased the frequency of total base substitutions. These results suggest that the type of DNA lesions which cause base substitutions were less often induced by 320-MeV 12 C 6+ than by γ-rays in Arabidopsis seedlings. Furthermore, γ-rays never increased the frequencies of G:C to T:A or A:T to C:G transversions, which are caused by oxidized guanine; 320-MeV 12 C 6+ , however, produced a slight increase in both transversions. Instead, γ-rays produced a significant increase in the frequency of G:C to A:T transitions. These results suggest that 8-oxoguanine has little effect on mutagenesis in Arabidopsis cells. (author)

The Simbox Experiment with Arabidopsis Thaliana Cell Cultures: Hardware-Tests and First Resutls from the German-Chinese satellite Mission Shenzhou 8

Science.gov (United States)

Fengler, Svenja; Neef, Maren; Ecke, Margret; Hampp, Ruediger

2013-02-01

The Simbox experiment was the first joint German-Chinese space project. In this context Arabidopsis thaliana cell cultures were exposed to microgravity for a 17-day period. To carry out a successful space mission, diverse hardware tests were performed in advance. Due to the limited oxygen supply inside the hardware units, cells were fixed after 5 days under microgravity conditions. As a control, samples were exposed in an on-board 1g reference centrifuge. To investigate the space effect, a ground-based study was performed with the same hardware and identical experimental procedures. As we were able to obtain high quality RNA from the RNAlater quenched samples, we used the Affymetrix Arabidopsis genome array for a transcriptome analysis. Our experiment aimed at the identification of plant genes that were differentially expressed after long-term exposure to microgravity. Pair-wise comparison of flight samples with 1g controls revealed the largest differences between space 1g and ground 1g controls.

Sugar regulation of SUGAR TRANSPORTER PROTEIN 1 (STP1) expression in Arabidopsis thaliana

Science.gov (United States)

Cordoba, Elizabeth; Aceves-Zamudio, Denise Lizeth; Hernández-Bernal, Alma Fabiola; Ramos-Vega, Maricela; León, Patricia

2015-01-01

Sugars regulate the expression of many genes at the transcriptional level. In Arabidopsis thaliana, sugars induce or repress the expression of >1800 genes, including the STP1 (SUGAR TRANSPORTER PROTEIN 1) gene, which encodes an H+/monosaccharide cotransporter. STP1 transcript levels decrease more rapidly after the addition of low concentrations of sugars than the levels of other repressed genes, such as DIN6 (DARK-INDUCED 6). We found that this regulation is exerted at the transcriptional level and is initiated by phosphorylatable sugars. Interestingly, the sugar signal that modulates STP1 expression is transmitted through a HEXOKINASE 1-independent signalling pathway. Finally, analysis of the STP1 5′ regulatory region allowed us to delimit a region of 309bp that contains the cis elements implicated in the glucose regulation of STP1 expression. Putative cis-acting elements involved in this response were identified. PMID:25281700

What is 5G? Emerging 5G Mobile Services and Network Requirements

OpenAIRE

Heejung Yu; Howon Lee; Hongbeom Jeon

2017-01-01

In this paper, emerging 5G mobile services are investigated and categorized from the perspective of not service providers, but end-users. The development of 5G mobile services is based on an intensive analysis of the global trends in mobile services. Additionally, several indispensable service requirements, essential for realizing service scenarios presented, are described. To illustrate the changes in societies and in daily life in the 5G era, five megatrends, including the explosion of mobi...

Arabidopsis CDS blastp result: AK110331 [KOME

Lifescience Database Archive (English)

Full Text Available AK110331 002-164-D12 At2g31510.1 IBR domain-containing protein / ARIADNE-like prote...in ARI7 (ARI7) identical to ARIADNE-like protein ARI7 [Arabidopsis thaliana] GI:29125028; contains similarit...y to Swiss-Prot:Q94981 ariadne-1 protein (Ari-1) [Drosophila melanogaster]; contains Pfam profile PF01485: IBR domain 3e-59 ...

A double-mutant collection targeting MAP kinase related genes in Arabidopsis for studying genetic interactions.

Science.gov (United States)

Su, Shih-Heng; Krysan, Patrick J

2016-12-01

Mitogen-activated protein kinase cascades are conserved in all eukaryotes. In Arabidopsis thaliana there are approximately 80 genes encoding MAP kinase kinase kinases (MAP3K), 10 genes encoding MAP kinase kinases (MAP2K), and 20 genes encoding MAP kinases (MAPK). Reverse genetic analysis has failed to reveal abnormal phenotypes for a majority of these genes. One strategy for uncovering gene function when single-mutant lines do not produce an informative phenotype is to perform a systematic genetic interaction screen whereby double-mutants are created from a large library of single-mutant lines. Here we describe a new collection of 275 double-mutant lines derived from a library of single-mutants targeting genes related to MAP kinase signaling. To facilitate this study, we developed a high-throughput double-mutant generating pipeline using a system for growing Arabidopsis seedlings in 96-well plates. A quantitative root growth assay was used to screen for evidence of genetic interactions in this double-mutant collection. Our screen revealed four genetic interactions, all of which caused synthetic enhancement of the root growth defects observed in a MAP kinase 4 (MPK4) single-mutant line. Seeds for this double-mutant collection are publicly available through the Arabidopsis Biological Resource Center. Scientists interested in diverse biological processes can now screen this double-mutant collection under a wide range of growth conditions in order to search for additional genetic interactions that may provide new insights into MAP kinase signaling. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

Identification of the yeast gene encoding the tRNA m1G methyltransferase responsible for modification at position 9.

Science.gov (United States)

Jackman, Jane E; Montange, Rebecca K; Malik, Harmit S; Phizicky, Eric M

2003-05-01

Methylation of tRNA at the N-1 position of guanosine to form m(1)G occurs widely in nature. It occurs at position 37 in tRNAs from all three kingdoms, and the methyltransferase that catalyzes this reaction is known from previous work of others to be critically important for cell growth in Escherichia coli and the yeast Saccharomyces cerevisiae. m(1)G is also widely found at position 9 in eukaryotic tRNAs, but the corresponding methyltransferase was unknown. We have used a biochemical genomics approach with a collection of purified yeast GST-ORF fusion proteins to show that m(1)G(9) formation of yeast tRNA(Gly) is associated with ORF YOL093w, named TRM10. Extracts lacking Trm10p have undetectable levels of m(1)G(9) methyltransferase activity but retain normal m(1)G(37) methyltransferase activity. Yeast Trm10p purified from E. coli quantitatively modifies the G(9) position of tRNA(Gly) in an S-adenosylmethionine-dependent fashion. Trm10p is responsible in vivo for most if not all m(1)G(9) modification of tRNAs, based on two results: tRNA(Gly) purified from a trm10-Delta/trm10-Delta strain is lacking detectable m(1)G; and a primer extension block occurring at m(1)G(9) is removed in trm10-Delta/trm10-Delta-derived tRNAs for all 9 m(1)G(9)-containing species that were testable by this method. There is no obvious growth defect of trm10-Delta/trm10-Delta strains. Trm10p bears no detectable resemblance to the yeast m(1)G(37) methyltransferase, Trm5p, or its orthologs. Trm10p homologs are found widely in eukaryotes and many archaea, with multiple homologs in several metazoans, including at least three in humans.

Reference: 495 [Arabidopsis Phenome Database[Archive

Lifescience Database Archive (English)

Full Text Available . Emission of methanethiol from Arabidopsis plants supplied with 10 mM L-methionine was undetectable (cation in an alternat...>homocysteine-->cystathionine-->cysteine) in which methanethiol is an intermediate. Functional characterizat...wth on L-methionine as sole nitrogen source and conferred a high rate of methanethiol emission. The purified...mol min(-1) g(-1) FW), suggesting that AtMGL is not an important source of volatile methanethiol. Knocking o

5G Spectrum Sharing

OpenAIRE

Nekovee, Maziar; Rudd, Richard

2017-01-01

In this paper an overview is given of the current status of 5G industry standards, spectrum allocation and use cases, followed by initial investigations of new opportunities for spectrum sharing in 5G using cognitive radio techniques, considering both licensed and unlicensed scenarios. A particular attention is given to sharing millimeter-wave frequencies, which are of prominent importance for 5G.

RNA Processing Factor 5 is required for efficient 5' cleavage at a processing site conserved in RNAs of three different mitochondrial genes in Arabidopsis thaliana.

Science.gov (United States)

Hauler, Aron; Jonietz, Christian; Stoll, Birgit; Stoll, Katrin; Braun, Hans-Peter; Binder, Stefan

2013-05-01

The 5' ends of many mitochondrial transcripts are generated post-transcriptionally. Recently, we identified three RNA PROCESSING FACTORs required for 5' end maturation of different mitochondrial mRNAs in Arabidopsis thaliana. All of these factors are pentatricopeptide repeat proteins (PPRPs), highly similar to RESTORERs OF FERTILTY (RF), that rescue male fertility in cytoplasmic male-sterile lines from different species. Therefore, we suggested a general role of these RF-like PPRPs in mitochondrial 5' processing. We now identified RNA PROCESSING FACTOR 5, a PPRP not classified as an RF-like protein, required for the efficient 5' maturation of the nad6 and atp9 mRNAs as well as 26S rRNA. The precursor molecules of these RNAs share conserved sequence elements, approximately ranging from positions -50 to +9 relative to mature 5' mRNA termini, suggesting these sequences to be at least part of the cis elements required for processing. The knockout of RPF5 has only a moderate influence on 5' processing of atp9 mRNA, whereas the generation of the mature nad6 mRNA and 26S rRNA is almost completely abolished in the mutant. The latter leads to a 50% decrease of total 26S rRNA species, resulting in an imbalance between the large rRNA and 18S rRNA. Despite these severe changes in RNA levels and in the proportion between the 26S and 18S rRNAs, mitochondrial protein levels appear to be unaltered in the mutant, whereas seed germination capacity is markedly reduced. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

Modified cellulose synthase gene from Arabidopsis thaliana confers herbicide resistance to plants

Science.gov (United States)

Somerville, Chris R [Portola Valley, CA; Scheible, Wolf [Golm, DE

2007-07-10

Cellulose synthase ("CS"), a key enzyme in the biosynthesis of cellulose in plants is inhibited by herbicides comprising thiazolidinones such as 5-tert-butyl-carbamoyloxy-3-(3-trifluromethyl)phenyl-4-thiazolidinone (TZ), isoxaben and 2,6-dichlorobenzonitrile (DCB). Two mutant genes encoding isoxaben and TZ-resistant cellulose synthase have been isolated from isoxaben and TZ-resistant Arabidopsis thaliana mutants. When compared with the gene coding for isoxaben or TZ-sensitive cellulose synthase, one of the resistant CS genes contains a point mutation, wherein glycine residue 998 is replaced by an aspartic acid. The other resistant mutation is due to a threonine to isoleucine change at amino acid residue 942. The mutant CS gene can be used to impart herbicide resistance to a plant; thereby permitting the utilization of the herbicide as a single application at a concentration which ensures the complete or substantially complete killing of weeds, while leaving the transgenic crop plant essentially undamaged.

Cloning and characterization of Sdga gene encoding alpha-subunit of heterotrimeric guanosine 5'-triphosphate-binding protein complex in Scoparia dulcis.

Science.gov (United States)

Shite, Masato; Yamamura, Yoshimi; Hayashi, Toshimitsu; Kurosaki, Fumiya

2008-11-01

A homology-based cloning strategy yielded Sdga, a cDNA clone presumably encoding alpha-subunit of heterotrimeric guanosine 5'-triphosphate-binding protein complex, from leaf tissues of Scoparia dulcis. Phylogenetic tree analysis of G-protein alpha-subunits from various biological sources suggested that, unlike in animal cells, classification of Galpha-proteins into specific subfamilies could not be applicable to the proteins from higher plants. Restriction digests of genomic DNA of S. dulcis showed a single hybridized signal in Southern blot analysis, suggesting that Sdga is a sole gene encoding Galpha-subunit in this plant. The expression level of Sdga appeared to be maintained at almost constant level after exposure of the leaves to methyl jasmonate as analyzed by reverse-transcription polymerase chain reaction. These results suggest that Sdga plays roles in methyl jasmonate-induced responses of S. dulcis without a notable change in the transcriptional level.

Structural and functional analysis of VQ motif-containing proteins in Arabidopsis as interacting proteins of WRKY transcription factors.

Science.gov (United States)

Cheng, Yuan; Zhou, Yuan; Yang, Yan; Chi, Ying-Jun; Zhou, Jie; Chen, Jian-Ye; Wang, Fei; Fan, Baofang; Shi, Kai; Zhou, Yan-Hong; Yu, Jing-Quan; Chen, Zhixiang

2012-06-01

WRKY transcription factors are encoded by a large gene superfamily with a broad range of roles in plants. Recently, several groups have reported that proteins containing a short VQ (FxxxVQxLTG) motif interact with WRKY proteins. We have recently discovered that two VQ proteins from Arabidopsis (Arabidopsis thaliana), SIGMA FACTOR-INTERACTING PROTEIN1 and SIGMA FACTOR-INTERACTING PROTEIN2, act as coactivators of WRKY33 in plant defense by specifically recognizing the C-terminal WRKY domain and stimulating the DNA-binding activity of WRKY33. In this study, we have analyzed the entire family of 34 structurally divergent VQ proteins from Arabidopsis. Yeast (Saccharomyces cerevisiae) two-hybrid assays showed that Arabidopsis VQ proteins interacted specifically with the C-terminal WRKY domains of group I and the sole WRKY domains of group IIc WRKY proteins. Using site-directed mutagenesis, we identified structural features of these two closely related groups of WRKY domains that are critical for interaction with VQ proteins. Quantitative reverse transcription polymerase chain reaction revealed that expression of a majority of Arabidopsis VQ genes was responsive to pathogen infection and salicylic acid treatment. Functional analysis using both knockout mutants and overexpression lines revealed strong phenotypes in growth, development, and susceptibility to pathogen infection. Altered phenotypes were substantially enhanced through cooverexpression of genes encoding interacting VQ and WRKY proteins. These findings indicate that VQ proteins play an important role in plant growth, development, and response to environmental conditions, most likely by acting as cofactors of group I and IIc WRKY transcription factors.

Mutations in LCA5, encoding the ciliary protein lebercilin, cause Leber congenital amaurosis.

NARCIS (Netherlands)

Hollander, A.I. den; Koenekoop, R.K.; Mohamed, M.D.; Arts, H.H.; Boldt, K.; Towns, K.V.; Sedmak, T.; Beer, M. de; Nagel-Wolfrum, K.; McKibbin, M.; Dharmaraj, S.; Lopez, I.; Ivings, L.; Williams, G.A.; Springell, K.; Woods, C.G.; Jafri, H.; Rashid, Y.; Strom, T.M.; Zwaag, B. van der; Gosens, I.; Kersten, F.F.J.; Wijk, E. van; Veltman, J.A.; Zonneveld, M.N.; Beersum, S.E.C. van; Maumenee, I.H.; Wolfrum, U.; Cheetham, M.E.; Ueffing, M.; Cremers, F.P.M.; Inglehearn, C.F.; Roepman, R.

2007-01-01

Leber congenital amaurosis (LCA) causes blindness or severe visual impairment at or within a few months of birth. Here we show, using homozygosity mapping, that the LCA5 gene on chromosome 6q14, which encodes the previously unknown ciliary protein lebercilin, is associated with this disease. We

Regulation of Flavonoid Biosynthetic Genes in Germinating Arabidopsis Seedlings.

Science.gov (United States)

Kubasek, WL; Shirley, BW; McKillop, A; Goodman, HM; Briggs, W; Ausubel, FM

1992-01-01

Many higher plants, including Arabidopsis, transiently display purple anthocyanin pigments just after seed germination. We observed that steady state levels of mRNAs encoded by four flavonoid biosynthetic genes, PAL1 (encoding phenylalanine ammonia-lyase 1), CHS (encoding chalcone synthase), CHI (encoding chalcone isomerase), and DFR (encoding dihydroflavonol reductase), were temporally regulated, peaking in 3-day-old seedlings grown in continuous white light. Except for the case of PAL1 mRNA, mRNA levels for these flavonoid genes were very low in seedlings grown in darkness. Light induction studies using seedlings grown in darkness showed that PAL1 mRNA began to accumulate before CHS and CHI mRNAs, which, in turn, began to accumulate before DFR mRNA. This order of induction is the same as the order of the biosynthetic steps in flavonoid biosynthesis. Our results suggest that the flavonoid biosynthetic pathway is coordinately regulated by a developmental timing mechanism during germination. Blue light and UVB light induction experiments using red light- and dark-grown seedlings showed that the flavonoid biosynthetic genes are induced most effectively by UVB light and that blue light induction is mediated by a specific blue light receptor. PMID:12297632

Arabidopsis C3HC4-RING finger E3 ubiquitin ligase AtAIRP4 positively regulates stress-responsive abscisic acid signaling.

Science.gov (United States)

Yang, Liang; Liu, Qiaohong; Liu, Zhibin; Yang, Hao; Wang, Jianmei; Li, Xufeng; Yang, Yi

2016-01-01

Degradation of proteins via the ubiquitin system is an important step in many stress signaling pathways in plants. E3 ligases recognize ligand proteins and dictate the high specificity of protein degradation, and thus, play a pivotal role in ubiquitination. Here, we identified a gene, named Arabidopsis thaliana abscisic acid (ABA)-insensitive RING protein 4 (AtAIRP4), which is induced by ABA and other stress treatments. AtAIRP4 encodes a cellular protein with a C3HC4-RING finger domain in its C-terminal side, which has in vitro E3 ligase activity. Loss of AtAIRP4 leads to a decrease in sensitivity of root elongation and stomatal closure to ABA, whereas overexpression of this gene in the T-DNA insertion mutant atairp4 effectively recovered the ABA-associated phenotypes. AtAIRP4 overexpression plants were hypersensitive to salt and osmotic stresses during seed germination, and showed drought avoidance compared with the wild-type and atairp4 mutant plants. In addition, the expression levels of ABA- and drought-induced marker genes in AtAIRP4 overexpression plants were markedly higher than those in the wild-type and atairp4 mutant plants. Hence, these results indicate that AtAIRP4 may act as a positive regulator of ABA-mediated drought avoidance and a negative regulator of salt tolerance in Arabidopsis. © 2015 The Authors. Journal of Integrative Plant Biology published by Wiley Publishing Asia Pty Ltd on behalf of Institute of Botany, Chinese Academy of Sciences.

Harpin-induced expression and transgenic overexpression of the phloem protein gene AtPP2-A1 in Arabidopsis repress phloem feeding of the green peach aphid Myzus persicae

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Sun Weiwei

2011-01-01

Full Text Available Abstract Background Treatment of plants with HrpNEa, a protein of harpin group produced by Gram-negative plant pathogenic bacteria, induces plant resistance to insect herbivores, including the green peach aphid Myzus persicae, a generalist phloem-feeding insect. Under attacks by phloem-feeding insects, plants defend themselves using the phloem-based defense mechanism, which is supposed to involve the phloem protein 2 (PP2, one of the most abundant proteins in the phloem sap. The purpose of this study was to obtain genetic evidence for the function of the Arabidopsis thaliana (Arabidopsis PP2-encoding gene AtPP2-A1 in resistance to M. persicae when the plant was treated with HrpNEa and after the plant was transformed with AtPP2-A1. Results The electrical penetration graph technique was used to visualize the phloem-feeding activities of apterous agamic M. persicae females on leaves of Arabidopsis plants treated with HrpNEa and an inactive protein control, respectively. A repression of phloem feeding was induced by HrpNEa in wild-type (WT Arabidopsis but not in atpp2-a1/E/142, the plant mutant that had a defect in the AtPP2-A1 gene, the most HrpNEa-responsive of 30 AtPP2 genes. In WT rather than atpp2-a1/E/142, the deterrent effect of HrpNEa treatment on the phloem-feeding activity accompanied an enhancement of AtPP2-A1 expression. In PP2OETAt (AtPP2-A1-overexpression transgenic Arabidopsis thaliana plants, abundant amounts of the AtPP2-A1 gene transcript were detected in different organs, including leaves, stems, calyces, and petals. All these organs had a deterrent effect on the phloem-feeding activity compared with the same organs of the transgenic control plant. When a large-scale aphid population was monitored for 24 hours, there was a significant decrease in the number of aphids that colonized leaves of HrpNEa-treated WT and PP2OETAt plants, respectively, compared with control plants. Conclusions The repression in phloem-feeding activities of

Harpin-induced expression and transgenic overexpression of the phloem protein gene AtPP2-A1 in Arabidopsis repress phloem feeding of the green peach aphid Myzus persicae.

Science.gov (United States)

Zhang, Chunling; Shi, Haojie; Chen, Lei; Wang, Xiaomeng; Lü, Beibei; Zhang, Shuping; Liang, Yuan; Liu, Ruoxue; Qian, Jun; Sun, Weiwei; You, Zhenzhen; Dong, Hansong

2011-01-13

Treatment of plants with HrpNEa, a protein of harpin group produced by Gram-negative plant pathogenic bacteria, induces plant resistance to insect herbivores, including the green peach aphid Myzus persicae, a generalist phloem-feeding insect. Under attacks by phloem-feeding insects, plants defend themselves using the phloem-based defense mechanism, which is supposed to involve the phloem protein 2 (PP2), one of the most abundant proteins in the phloem sap. The purpose of this study was to obtain genetic evidence for the function of the Arabidopsis thaliana (Arabidopsis) PP2-encoding gene AtPP2-A1 in resistance to M. persicae when the plant was treated with HrpNEa and after the plant was transformed with AtPP2-A1. The electrical penetration graph technique was used to visualize the phloem-feeding activities of apterous agamic M. persicae females on leaves of Arabidopsis plants treated with HrpNEa and an inactive protein control, respectively. A repression of phloem feeding was induced by HrpNEa in wild-type (WT) Arabidopsis but not in atpp2-a1/E/142, the plant mutant that had a defect in the AtPP2-A1 gene, the most HrpNEa-responsive of 30 AtPP2 genes. In WT rather than atpp2-a1/E/142, the deterrent effect of HrpNEa treatment on the phloem-feeding activity accompanied an enhancement of AtPP2-A1 expression. In PP2OETAt (AtPP2-A1-overexpression transgenic Arabidopsis thaliana) plants, abundant amounts of the AtPP2-A1 gene transcript were detected in different organs, including leaves, stems, calyces, and petals. All these organs had a deterrent effect on the phloem-feeding activity compared with the same organs of the transgenic control plant. When a large-scale aphid population was monitored for 24 hours, there was a significant decrease in the number of aphids that colonized leaves of HrpNEa-treated WT and PP2OETAt plants, respectively, compared with control plants. The repression in phloem-feeding activities of M. persicae as a result of AtPP2-A1 overexpression, and

Arabidopsis Yak1 protein (AtYak1) is a dual specificity protein kinase

KAUST Repository

Kim, Dongjin; Ntui, Valentine Otang; Zhang, Nianshu; Xiong, Liming

2015-01-01

Yak1 is a member of dual-specificity Tyr phosphorylation-regulated kinases (DYRKs) that are evolutionarily conserved. The downstream targets of Yak1 and their functions are largely unknown. Here, a homologous protein AtYAK1 was identified in Arabidopsis thaliana and the phosphoprotein profiles of the wild type and an atyak1 mutant were compared on two-dimensional gel following Pro-Q Diamond phosphoprotein gel staining. Annexin1, Annexin2 and RBD were phosphorylated at serine/ threonine residues by the AtYak1 kinase. Annexin1, Annexin2 and Annexin4 were also phosphorylated at tyrosine residues. Our study demonstrated that AtYak1 is a dual specificity protein kinase in Arabidopsis that may regulate the phosphorylation status of the annexin family proteins.

Arabidopsis Yak1 protein (AtYak1) is a dual specificity protein kinase

KAUST Repository

Kim, Dongjin

2015-10-09

Yak1 is a member of dual-specificity Tyr phosphorylation-regulated kinases (DYRKs) that are evolutionarily conserved. The downstream targets of Yak1 and their functions are largely unknown. Here, a homologous protein AtYAK1 was identified in Arabidopsis thaliana and the phosphoprotein profiles of the wild type and an atyak1 mutant were compared on two-dimensional gel following Pro-Q Diamond phosphoprotein gel staining. Annexin1, Annexin2 and RBD were phosphorylated at serine/ threonine residues by the AtYak1 kinase. Annexin1, Annexin2 and Annexin4 were also phosphorylated at tyrosine residues. Our study demonstrated that AtYak1 is a dual specificity protein kinase in Arabidopsis that may regulate the phosphorylation status of the annexin family proteins.

Durum wheat dehydrin (DHN-5) confers salinity tolerance to transgenic Arabidopsis plants through the regulation of proline metabolism and ROS scavenging system.

Science.gov (United States)

Saibi, Walid; Feki, Kaouthar; Ben Mahmoud, Rihem; Brini, Faiçal

2015-11-01

The wheat dehydrin (DHN-5) gives birth to salinity tolerance to transgenic Arabidopsis plants by the regulation of proline metabolism and the ROS scavenging system. Dehydrins (DHNs) are involved in plant abiotic stress tolerance. In this study, we reported that salt tolerance of transgenic Arabidopsis plants overexpressing durum wheat dehydrin (DHN-5) was closely related to the activation of the proline metabolism enzyme (P5CS) and some antioxidant biocatalysts. Indeed, DHN-5 improved P5CS activity in the transgenic plants generating a significant proline accumulation. Moreover, salt tolerance of Arabidopsis transgenic plants was accompanied by an excellent activation of antioxidant enzymes like catalase (CAT), superoxide dismutase (SOD) and peroxide dismutase (POD) and generation of a lower level of hydrogen peroxide (H2O2) in leaves compared to the wild-type plants. The enzyme activities were enhanced in these transgenic plants in the presence of exogenous proline. Nevertheless, proline accumulation was slightly reduced in transgenic plants promoting chlorophyll levels. All these results suggest the crucial role of DHN-5 in response to salt stress through the activation of enzymes implicated in proline metabolism and in ROS scavenging enzymes.

Seed-specific overexpression of AtFAX1 increases seed oil content in Arabidopsis.

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Tian, Yinshuai; Lv, Xueyan; Xie, Guilan; Zhang, Jing; Xu, Ying; Chen, Fang

2018-06-02

Biosynthesis of plant seed oil is accomplished through the coordinate action of multiple enzymes in multiple subcellular compartments. Fatty acid (FA) has to be transported from plastid to endoplasmic reticulum (ER) for TAG synthesis. However, the role of plastid FA transportation during seed oil accumulation has not been evaluated. AtFAX1 (Arabidopsis fatty acid export1) mediated the FA export from plastid. In this study, we overexpressed AtFAX1 under the control of a seed specific promoter in Arabidopsis. The resultant overexpression lines (OEs) produced seeds which contained 21-33% more oil and 24-30% more protein per seed than those of the wild type (WT). The increased oil content was probably because of the enhanced FA and TAG synthetic activity. The seed size and weight were both increased accordingly. In addition, the seed number per silique and silique number per plant had no changes in transgenic plants. Taken together, our results demonstrated that seed specific overexpression of AtFAX1 could promote oil accumulation in Arabidopsis seeds and manipulating FA transportation is a feasible strategy for increasing the seed oil content. Copyright © 2018 Elsevier Inc. All rights reserved.

Gravity-regulated gene expression in Arabidopsis thaliana

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Sederoff, Heike; Brown, Christopher S.; Heber, Steffen; Kajla, Jyoti D.; Kumar, Sandeep; Lomax, Terri L.; Wheeler, Benjamin; Yalamanchili, Roopa

Plant growth and development is regulated by changes in environmental signals. Plants sense environmental changes and respond to them by modifying gene expression programs to ad-just cell growth, differentiation, and metabolism. Functional expression of genes comprises many different processes including transcription, translation, post-transcriptional and post-translational modifications, as well as the degradation of RNA and proteins. Recently, it was discovered that small RNAs (sRNA, 18-24 nucleotides long), which are heritable and systemic, are key elements in regulating gene expression in response to biotic and abiotic changes. Sev-eral different classes of sRNAs have been identified that are part of a non-cell autonomous and phloem-mobile network of regulators affecting transcript stability, translational kinetics, and DNA methylation patterns responsible for heritable transcriptional silencing (epigenetics). Our research has focused on gene expression changes in response to gravistimulation of Arabidopsis roots. Using high-throughput technologies including microarrays and 454 sequencing, we iden-tified rapid changes in transcript abundance of genes as well as differential expression of small RNA in Arabidopsis root apices after minutes of reorientation. Some of the differentially regu-lated transcripts are encoded by genes that are important for the bending response. Functional mutants of those genes respond faster to reorientation than the respective wild type plants, indicating that these proteins are repressors of differential cell elongation. We compared the gravity responsive sRNAs to the changes in transcript abundances of their putative targets and identified several potential miRNA: target pairs. Currently, we are using mutant and transgenic Arabidopsis plants to characterize the function of those miRNAs and their putative targets in gravitropic and phototropic responses in Arabidopsis.

Arabidopsis CDS blastp result: AK242789 [KOME

Lifescience Database Archive (English)

Full Text Available AK242789 J090057B20 At2g31510.1 68415.m03850 IBR domain-containing protein / ARIADN...E-like protein ARI7 (ARI7) identical to ARIADNE-like protein ARI7 [Arabidopsis thaliana] GI:29125028; contai...ns similarity to Swiss-Prot:Q94981 ariadne-1 protein (Ari-1) [Drosophila melanogaster]; contains Pfam profile PF01485: IBR domain 8e-12 ...

Expression of TpNRAMP5, a metal transporter from Polish wheat (Triticum polonicum L.), enhances the accumulation of Cd, Co and Mn in transgenic Arabidopsis plants.

Science.gov (United States)

Peng, Fan; Wang, Chao; Zhu, Jianshu; Zeng, Jian; Kang, Houyang; Fan, Xing; Sha, Lina; Zhang, Haiqin; Zhou, Yonghong; Wang, Yi

2018-06-01

TpRNAMP5 is mainly expressed in the plasma membrane of roots and basal stems. It functions as a metal transporter for Cd, Mn and Co accumulation. Numerous natural resistance-associated macrophage proteins (NRAMPs) have been functionally identified in various plant species, including Arabidopsis, rice, soybean and tobacco, but no information is available on NRAMP genes in wheat. In this study, we isolated a TpNRAMP5 from dwarf Polish wheat (DPW, Triticum polonicum L.), a species with high tolerance to Cd and Zn. Expression pattern analysis revealed that TpNRAMP5 is mainly expressed in roots and basal stems of DPW. TpNRAMP5 was localized at the plasma membrane of Arabidopsis leaf protoplast. Expression of TpNRAMP5 in yeast significantly increased yeast sensitivity to Cd and Co, but not Zn, and enhanced Cd and Co concentrations. Expression of TpNRAMP5 in Arabidopsis significantly increased Cd, Co and Mn concentrations in roots, shoots and whole plants, but had no effect on Fe and Zn concentrations. These results indicate that TpNRAMP5 is a metal transporter enhancing the accumulation of Cd, Co and Mn, but not Zn and Fe. Genetic manipulation of TpNRAMP5 can be applied in the future to limit the transfer of Cd from soil to wheat grains, thereby protecting human health.

Functional divergence of chloroplast Cpn60α subunits during Arabidopsis embryo development.

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Xiaolong Ke

2017-09-01

Full Text Available Chaperonins are a class of molecular chaperones that assist in the folding and assembly of a wide range of substrates. In plants, chloroplast chaperonins are composed of two different types of subunits, Cpn60α and Cpn60β, and duplication of Cpn60α and Cpn60β genes occurs in a high proportion of plants. However, the importance of multiple Cpn60α and Cpn60β genes in plants is poorly understood. In this study, we found that loss-of-function of CPNA2 (AtCpn60α2, a gene encoding the minor Cpn60α subunit in Arabidopsis thaliana, resulted in arrested embryo development at the globular stage, whereas the other AtCpn60α gene encoding the dominant Cpn60α subunit, CPNA1 (AtCpn60α1, mainly affected embryonic cotyledon development at the torpedo stage and thereafter. Further studies demonstrated that CPNA2 can form a functional chaperonin with CPNB2 (AtCpn60β2 and CPNB3 (AtCpn60β3, while the functional partners of CPNA1 are CPNB1 (AtCpn60β1 and CPNB2. We also revealed that the functional chaperonin containing CPNA2 could assist the folding of a specific substrate, KASI (β-ketoacyl-[acyl carrier protein] synthase I, and that the KASI protein level was remarkably reduced due to loss-of-function of CPNA2. Furthermore, the reduction in the KASI protein level was shown to be the possible cause for the arrest of cpna2 embryos. Our findings indicate that the two Cpn60α subunits in Arabidopsis play different roles during embryo development through forming distinct chaperonins with specific AtCpn60β to assist the folding of particular substrates, thus providing novel insights into functional divergence of Cpn60α subunits in plants.

Adaptation response of Arabidopsis thaliana to random positioning

Science.gov (United States)

Kittang, A.-I.; Winge, P.; van Loon, J. J. W. A.; Bones, A. M.; Iversen, T.-H.

2013-10-01

Arabidopsis thaliana seedlings were exposed on a Random Positioning Machine (RPM) under light conditions for 16 h and the samples were analysed using microarray techniques as part of a preparation for a space experiment on the International Space Station (ISS). The results demonstrated a moderate to low regulation of 55 genes (genes). Genes encoding proteins associated with the chaperone system (e.g. heat shock proteins, HSPs) and enzymes in the flavonoid biosynthesis were induced. Most of the repressed genes were associated with light and sugar responses. Significant up-regulation of selected HSP genes was found by quantitative Real-Time PCR in 1 week old plants after the RPM exposure both in light and darkness. Higher quantity of DPBA (diphenylboric acid 2-amino-ethyl ester) staining was observed in the whole root and in the root elongation zone of the seedlings exposed on the RPM by use of fluorescent microscopy, indicating higher flavonoid content. The regulated genes and an increase of flavonoids are related to several stresses, but increased occurrence of HSPs and flavonoids are also representative for normal growth (e.g. gravitropism). The response could be a direct stress response or an integrated response of the two signal pathways of light and gravity resulting in an overall light response.

Variation in the Subcellular Localization and Protein Folding Activity among Arabidopsis thaliana Homologs of Protein Disulfide Isomerase

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Christen Y. L. Yuen

2013-10-01

Full Text Available Protein disulfide isomerases (PDIs catalyze the formation, breakage, and rearrangement of disulfide bonds to properly fold nascent polypeptides within the endoplasmic reticulum (ER. Classical animal and yeast PDIs possess two catalytic thioredoxin-like domains (a, a′ and two non-catalytic domains (b, b′, in the order a-b-b′-a′. The model plant, Arabidopsis thaliana, encodes 12 PDI-like proteins, six of which possess the classical PDI domain arrangement (AtPDI1 through AtPDI6. Three additional AtPDIs (AtPDI9, AtPDI10, AtPDI11 possess two thioredoxin domains, but without intervening b-b′ domains. C-terminal green fluorescent protein (GFP fusions to each of the nine dual-thioredoxin PDI homologs localized predominantly to the ER lumen when transiently expressed in protoplasts. Additionally, expression of AtPDI9:GFP-KDEL and AtPDI10: GFP-KDDL was associated with the formation of ER bodies. AtPDI9, AtPDI10, and AtPDI11 mediated the oxidative folding of alkaline phosphatase when heterologously expressed in the Escherichia coli protein folding mutant, dsbA−. However, only three classical AtPDIs (AtPDI2, AtPDI5, AtPDI6 functionally complemented dsbA−. Interestingly, chemical inducers of the ER unfolded protein response were previously shown to upregulate most of the AtPDIs that complemented dsbA−. The results indicate that Arabidopsis PDIs differ in their localization and protein folding activities to fulfill distinct molecular functions in the ER.

IBR5 Modulates Temperature-Dependent, R Protein CHS3-Mediated Defense Responses in Arabidopsis.

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Jingyan Liu

2015-10-01

Full Text Available Plant responses to low temperature are tightly associated with defense responses. We previously characterized the chilling-sensitive mutant chs3-1 resulting from the activation of the Toll and interleukin 1 receptor-nucleotide binding-leucine-rich repeat (TIR-NB-LRR-type resistance (R protein harboring a C-terminal LIM (Lin-11, Isl-1 and Mec-3 domains domain. Here we report the identification of a suppressor of chs3, ibr5-7 (indole-3-butyric acid response 5, which largely suppresses chilling-activated defense responses. IBR5 encodes a putative dual-specificity protein phosphatase. The accumulation of CHS3 protein at chilling temperatures is inhibited by the IBR5 mutation. Moreover, chs3-conferred defense phenotypes were synergistically suppressed by mutations in HSP90 and IBR5. Further analysis showed that IBR5, with holdase activity, physically associates with CHS3, HSP90 and SGT1b (Suppressor of the G2 allele of skp1 to form a complex that protects CHS3. In addition to the positive role of IBR5 in regulating CHS3, IBR5 is also involved in defense responses mediated by R genes, including SNC1 (Suppressor of npr1-1, Constitutive 1, RPS4 (Resistance to P. syringae 4 and RPM1 (Resistance to Pseudomonas syringae pv. maculicola 1. Thus, the results of the present study reveal a role for IBR5 in the regulation of multiple R protein-mediated defense responses.

Do dorsal raphe 5-HT neurons encode "beneficialness"?

Science.gov (United States)

Luo, Minmin; Li, Yi; Zhong, Weixin

2016-11-01

The neurotransmitter serotonin (5-hydroxytryptamine; 5-HT) affects numerous behavioral and physiological processes. Drugs that alter 5-HT signaling treat several major psychiatric disorders and may lead to widespread abuse. The dorsal raphe nucleus (DRN) in the midbrain provides a majority of 5-HT for the forebrain. The importance of 5-HT signaling propels the search for a general theoretical framework under which the diverse functions of the DRN 5-HT neurons can be interpreted and additional therapeutic solutions may be developed. However, experimental data so far support several seeming irreconcilable theories, suggesting that 5-HT neurons mediate behavioral inhibition, aversive processing, or reward signaling. Here, we review recent progresses and propose that DRN 5-HT neurons encode "beneficialness" - how beneficial the current environmental context represents for an individual. Specifically, we speculate that the activity of these neurons reflects the possible net benefit of the current context as determined by p·R-C, in which p indicates reward probability, R the reward value, and C the cost. Through the widespread projections of these neurons to the forebrain, the beneficialness signal may reconfigure neural circuits to bias perception, boost positive emotions, and switch behavioral choices. The "beneficialness" hypothesis can explain many conflicting observations, and at the same time raises new questions. We suggest additional experiments that will help elucidate the exact computational functions of the DRN 5-HT neurons. Copyright © 2016 Elsevier Inc. All rights reserved.

The Genetic Basis of Constitutive and Herbivore-Induced ESP-Independent Nitrile Formation in Arabidopsis1[W][OA

Science.gov (United States)

Burow, Meike; Losansky, Anja; Müller, René; Plock, Antje; Kliebenstein, Daniel J.; Wittstock, Ute

2009-01-01

Glucosinolates are a group of thioglucosides that are components of an activated chemical defense found in the Brassicales. Plant tissue damage results in hydrolysis of glucosinolates by endogenous thioglucosidases known as myrosinases. Spontaneous rearrangement of the aglucone yields reactive isothiocyanates that are toxic to many organisms. In the presence of specifier proteins, alternative products, namely epithionitriles, simple nitriles, and thiocyanates with different biological activities, are formed at the expense of isothiocyanates. Recently, simple nitriles were recognized to serve distinct functions in plant-insect interactions. Here, we show that simple nitrile formation in Arabidopsis (Arabidopsis thaliana) ecotype Columbia-0 rosette leaves increases in response to herbivory and that this increase is independent of the known epithiospecifier protein (ESP). We combined phylogenetic analysis, a screen of Arabidopsis mutants, recombinant protein characterization, and expression quantitative trait locus mapping to identify a gene encoding a nitrile-specifier protein (NSP) responsible for constitutive and herbivore-induced simple nitrile formation in Columbia-0 rosette leaves. AtNSP1 is one of five Arabidopsis ESP homologues that promote simple nitrile, but not epithionitrile or thiocyanate, formation. Four of these homologues possess one or two lectin-like jacalin domains, which share a common ancestry with the jacalin domains of the putative Arabidopsis myrosinase-binding proteins MBP1 and MBP2. A sixth ESP homologue lacked specifier activity and likely represents the ancestor of the gene family with a different biochemical function. By illuminating the genetic and biochemical bases of simple nitrile formation, our study provides new insights into the evolution of metabolic diversity in a complex plant defense system. PMID:18987211

Natural modifiers of seed longevity in the Arabidopsis mutants abscisic acid insensitive3-5 (abi3-5) and leafy cotyledon1-3 (lec1-3)

NARCIS (Netherlands)

Sugliani, M.R.L.; Rajjou, L.; Clerkx, E.J.M.; Koornneef, M.; Soppe, W.J.J.

2009-01-01

• Seed longevity is an important trait in many crops and is essential for the success of most land plant species. Current knowledge of its molecular regulation is limited. The Arabidopsis mutants abscisic acid insensitive3-5 (abi3-5) and leafy cotyledon1-3 (lec1-3) have impaired seed maturation and

Hypermutability of CpG dinucleotides in the propeptide-encoding sequence of the human albumin gene

International Nuclear Information System (INIS)