Tumor necrosis factor alpha (TNFalpha) inhibits insulin action, in part, through serine phosphorylation of IRS proteins; however, the sites that mediate inhibition are unknown. TNFalpha promotes multipotential signal transduction cascades, including activation Jun NH(2)-terminal kinase (JNK). Endogenous JNK associates with IRS-1 Chinese hamster ovary cells. Anisomycin, a strong activator these cells, stimulates activity bound to and insulin-stimulated tyrosine IRS-1. Serine 307 is major site...

GRB-2 is a small SH2- and SH3 domain-containing adapter protein that associates with the mammalian SOS homolog to regulate p21ras during growth factor signaling. During insulin stimulation, binds phosphorylated Y895VNI motif of IRS-1. Substitution Tyr-895 phenylalanine (IRS-1F-895) prevented IRS-1-GRB-2 association in vivo vitro. The myeloid progenitor cell line, 32-D, insensitive because it contains few receptors no Coexpression IRS-1 or IRS-1F-895 receptor was required for...

Interferon-α (IFNα) induces rapid tyrosine phosphorylation of the insulin receptor substrate-1 (IRS-1), a docking protein with multiple sites that bind to Src homology 2 (SH2) domains various signaling proteins. During IFNα stimulation, p85 regulatory subunit phosphatidylinositol 3′-kinase binds via its SH2 tyrosine-phosphorylated IRS-1, and activity is detected in association IRS-1. Thus, responses occur by activation IRS system, which it shares insulin, insulin-like growth factor-1,...

Potassium is the major cation responsible for maintenance of ionic environment in plant cells. Stable potassium homeostasis indispensable virtually all cellular functions, and, concomitantly, viability. Plants must cope with environmental changes such as salt or drought that can alter homeostasis. fluxes are required to regulate essential process transpiration, so a constraint on transport may also affect plant's response heat, cold, oxidative stress. Sequencing data and functional analyses...

Interaction domains located in the NH2 terminus of IRS-1 mediate its recognition by insulin receptor. Alignment and IRS-2 reveals two homology regions: IH1PH contains a pleckstrin (PH) domain, IH2PTB phosphotyrosine binding (PTB) domain. A third region called SAIN was proposed to contain another functional PTB Peptide competition experiments demonstrated that IRS-2, like corresponding domain IRS-1, binds directly peptides containing NPXY motifs. In contrast, these do not bind or regions. 32D...

The temporal activation of E2F transcriptional activity appears to be an important component the mechanisms that prepare mammalian cells for DNA replication. Regulation a highly complex process, and dissection pathway will greatly facilitated by ability use genetic approaches. We report isolation two Drosophila genes can stimulate E2F-dependent transcription in cells. One these genes, dE2F, contains three domains are conserved human homologs E2F-1, E2F-2, E2F-3. Interestingly, one is...

Signal transduction by insulin and IGF-1, several interleukins (IL-2, IL-4, IL-9, IL-13), interferons, GH, other cytokines involves IRS proteins, which link the receptors for these factors to signaling molecules with Src homology-2 domains (SH2-proteins). We recently reported amino acid sequence of murine IRS-2; in order examine a potential genetic role this molecule disease, we isolated IRS-2 gene compared expression pattern against IRS-1. Like IRS-1, is encoded single exon. Whereas IRS-1...

Seed longevity is crucial for agriculture and plant genetic diversity, but it limited by cellular damage during storage. Seeds are protected against aging defenses structures such as the seed coat. We have screened an activation-tagging mutant collection of Arabidopsis (Arabidopsis thaliana) selected four dominant mutants with improved (isl1-1D to isl4-1D) under both natural accelerated conditions. In isl1-1D mutant, characterized in this work, overexpression transcription factor ARABIDOPSIS...

Tomato plants expressing the NahG transgene, which prevents accumulation of endogenous salicylic acid (SA), were used to study importance SA signalling pathway in basal defence against Citrus Exocortis Viroid (CEVd) or Spotted Wilt Virus (TSWV). The lack CEVd- TSWV-infected tomato led an early and dramatic disease phenotype, as compared that observed corresponding parental Money Maker. Addition acibenzolar-S-methyl, a benzothiadiazole (BTH), activates systemic acquired resistance downstream...

Abstract Viruses are obligate intracellular parasites that have co-evolved with their hosts to establish an intricate network of protein–protein interactions. Here, we followed a high-throughput yeast two-hybrid screening identify 378 novel interactions between turnip mosaic virus (TuMV) and its natural host Arabidopsis thaliana . We identified the RNA-dependent RNA polymerase NIb as viral protein largest number contacts, including key salicylic acid-dependent transcription regulators....

Salinization poses a significant challenge in agriculture, exacerbated by anthropogenic global warming. Biostimulants, derived from living microorganisms or natural extracts, have emerged as valuable tools for conventional and organic agriculture. However, our understanding of the molecular mechanisms underlying effects biostimulants is very limited, especially crops under real cultivation conditions. In this study, we adopted an integrative approach to investigate effectiveness combined...

Summary Protein synthesis is very sensitive to NaCl. However, the molecular targets responsible for this sensitivity have not been described. A cDNA library of halotolerant plant sugar beet was functionally screened in a sodium‐sensitive yeast strain. We obtained clone ( BveIF1A ) encoding eukaryotic translation initiation factor eIF1A. able partially complement eIF1A‐deficient Overexpression eIF1A specifically increased sodium and lithium salt tolerance yeast. This phenotype accompanied by...

Intracellular pH and K+ concentrations must be tightly controlled because they affect many cellular activities, including cell growth death. The mechanisms of homeostasis H+ are only partially understood. In the yeast Saccharomyces cerevisiae, proton efflux is mediated by Pma1 H+-ATPase. As this pump electrogenic, activity Trk1 -2 uptake system crucial for sustained Pma1p operation. coordinated activities these two systems determine volume, turgor, membrane potential, pH. Genetic evidence...

Stomata govern the gaseous exchange between leaf and external atmosphere, their function is essential for photosynthesis global carbon oxygen cycles. Rhythmic stomata movements in daily dark/light cycles prevent water loss at night allow CO2 uptake during day. How actors involved are transcriptionally regulated how this might contribute to rhythmicity largely unknown. Here, we show that morning opening depends on previous period. The transcription factors PHYTOCHROME-INTERACTING FACTORS...

Tyrosine phosphorylation of insulin receptor substrate 1 (IRS-1) by the activated receptors for insulin, IGF-1, and various cytokines creates binding sites signaling proteins with Src homology 2 domains (SH2 proteins). Determining role specific SH2 during has been difficult because IRS-1 possesses as many 18 potential tyrosine sites, several which contain redundant motifs. Using 32D cells, no endogenous IRS proteins, we compared ability an molecule in were replaced phenylalanine (IRS-1(F18))...

The Drosophila insulin receptor (DIR) contains a 368-amino-acid COOH-terminal extension that several tyrosine phosphorylation sites in YXXM motifs. This is absent from the human but resembles region substrate (IRS) proteins which binds to phosphatidylinositol (PI) 3-kinase and mediates mitogenesis. function of chimeric DIR containing binding domain (hDIR) was investigated 32D cells, contain few receptors no IRS proteins. Insulin stimulated autophosphorylation hDIR, both mediated Shc...