Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.16 (calcineurin)
 17,112 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To investigate the involvement of protein kinases in the signaling cascade that leads to hypersensitive cell death, we used a previously established system in which a fungal elicitor, xylanase from Trichoderma viride (TvX), induces a hypersensitive reaction in tobacco (Nicotiana tabacum) cells in culture (line XD6S). The elicitor induced the slow and prolonged activation of a p47 protein kinase, which has the characteristics of a family member of the mitogen-activated protein kinases. An inhibitor of protein kinases, staurosporine, and a blocker of Ca channels, Gd3+ ions, both of which blocked the TvX-induced hypersensitive cell death, inhibited the TvX-induced activation of p47 protein kinase. Moreover, an inhibitor of serine/threonine protein phosphatase alone induced both rapid cell death and the persistent activation of the p47 protein kinase. Thus, the p47 protein kinase might be a component of the signal transduction pathway that leads to hypersensitive cell death, and the regulation of the duration of activation of the p47 protein kinase might be important in determining the destiny of tobacco cells.
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PMID:Slow and prolonged activation of the p47 protein kinase during hypersensitive cell death in a culture of tobacco cells 1019 6

In cultured XD6S tobacco cells, xylanase from Trichoderma viride (TvX) induced the expression of a luciferase reporter gene that was under the control of a GCC box, which is an 11 bp sequence (TAAGAGCCGCC) that is found in the 5'-upstream region of pathogen-responsive defence genes that include genes for class I basic chitinase. TvX-induced biosynthesis of ethylene was not required for the TvX-activated transcription. The TvX-induced, GCC box-mediated transcription of the reporter gene was completely blocked not only by staurosporine, an inhibitor of serine/threonine protein kinases, at 1 microM, but also by calyculin A, an inhibitor of protein phosphatases 1 and 2A, at 0.2 microM. It appeared also that protein synthesis de novo was required for the GCC box-mediated transcription of the reporter gene. Accumulation of mRNAs for various ERFs (ethylene-responsive transcription factors), which have been shown to bind specifically to the GCC box, was also induced by TvX prior to increases in the level of mRNA for a class I basic chitinase. In particular, the level of mRNA for EFR2 reached a maximum from 3 to 6 h, whereas levels of mRNAs for ERF3 and ERF4 were highest 0.5 h after the start of treatment of TvX and decreased thereafter. Moreover, induction of accumulation of the mRNA for ERF2 was inhibited by staurosporine and calyculin A. These results suggest that ERF2 might play a major role in TvX-induced, GCC box-mediated transcription of genes and that both protein kinase(s) and protein phosphatase(s) might be involved, as positive regulators, in the signal transduction pathway that leads to expression of ERF2 and subsequent GCC box-mediated transcription of genes.
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PMID:Elicitor-responsive, ethylene-independent activation of GCC box-mediated transcription that is regulated by both protein phosphorylation and dephosphorylation in cultured tobacco cells. 1065 29

Suspension-cultured tomato cells react to microbial signals, so-called elicitors, with rapid alkalinization of the growth medium and increased biosynthesis of the stress hormone ethylene. These responses to elicitors can be blocked by staurosporine and K-252a, two specific inhibitors of protein kinases. Here we show that calyculin A, a potent inhibitor of protein phosphatases, mimics the action of elicitors and, at nanomolar concentrations, induces medium alkalinization as well as a strong increase in the activity of 1-aminocyclopropane-1-carboxylate synthase, the key enzyme of ethylene biosynthesis. Both responses were strongly inhibited by K-252a, and calyculin A induced both responses more rapidly than did a fungal elicitor, xylanase. For example, the lag phase for medium alkalinization was only 0.2-0.4 min for calyculin A, compared with 2 min for xylanase. To study changes in the dynamics of protein phosphorylation, cells were labeled with 30-sec pulses of [33P]orthophosphate. Calyculin A strongly increased phosphorylation of several polypeptide bands within 40 sec of treatment. The same phosphorylated bands also appeared in response to xylanase, but only after a lag phase of 2-3 min. These results show that the protein phosphatase inhibitor calyculin A leads to rapid hyperphosphorylation of specific proteins in cultured cells and indicate that elicitor action could be based on inhibition of a protein phosphatase as well as on activation of a protein kinase.
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PMID:The protein phosphatase inhibitor calyculin A mimics elicitor action in plant cells and induces rapid hyperphosphorylation of specific proteins as revealed by pulse labeling with [33P]phosphate. 1160 54