Mitogen-activated protein kinases mechanisms

The OP group of receptois share common effector mechanisms. All receptois couple via pertussis toxin-sensitive Go and Gi proteins leading to (i) inhibition of adenylate cyclase (ii) reduction of Ca2+ currents via diverse Ca2+ channels (hi) activation of inward rectifying K+ channels. In addition, the majority of these receptors cause the activation of phospholipase A2 (PLA2), phospholipase C 3 (PLC 3), phospholipase D2 and of MAP (mitogen-activated protein) kinase (Table 3). 

The biochemical mechanism of Mos action is not yet established. Mos has been found to phosphorylate cyclin B in vitro, and it is possible that this phosphorylation directly inhibits cyclin B proteolysis (Roy et al., 1990). However, such a direct effect of phosphorylation on cyclin B stability remains to be demonstrated, and it is alternatively possible that Mos inhibits (directly or indirectly) the proteolytic pathway responsible for cyclin B degradation. Mos has recently been found to stimulate mitogen-activated protein kinase (MAP kinase) in Xenopus oocytes,... 

Dineley, K.T., Westerman, M., Bui, D., Bell, K., Ashe, K.H., Sweatt, J.D. Beta-amyloid activates the mitogen-activated protein kinase cascade via hippocampal alpha7 nicotinic acetylcholine receptors in vitro and in vivo mechanisms related to Alzheimer s disease. J. Neurosci. 21 4125, 2001. 

Kang, Y. J., Seit-Nebi, A., Davis, R. J., and Han, J. (2006). Multiple activation mechanisms ofp38alpha mitogen-activated protein kinase. /. Biol. Chem. 281, 26225—26234. 

The catalytic activity of cPLA2 is stimulated by phosphorylation catalyzed by the mitogen-activated protein kinase (MAPK) at Ser505. This modification stimulates enzyme activity only, indicating that translocation and phosphorylation are independent mechanisms of cPLA2 regulation [21]. 

Fiebich, B. L., Schleicher, S., Spleiss, O., Czygan, M. and Hull, M. Mechanisms of prostaglandin E2-induced interleukin-6 release in astrocytes possible involvement of EP4-like receptors, p38 mitogen-activated protein kinase and protein kinase C. /. Neurochem. 5 950-958,2001. 

What are the mechanisms by which trichothecenes exert their transcriptional and post-transcriptional effects The 60S ribosomal subunit is a well-known molecular target of trichothecenes in leukocytes and other actively proliferating eukaryotic cells,3 whereas attempts to demonstrate alternative receptors have not been successful.37 38 Translational inhibitors that bind to ribosomes rapidly activate mitogen-activated protein kinases (MAPKs) and apoptosis via a mechanism termed the ribotoxic stress response. 39-40... 

Pedersen IM, Buhl AM, Klausen P et al. The chimeric anti-CD20 antibody rituximab induces apoptosis in B-cell ehronie lymphoeytie leukemia cells through a p38 mitogen activated protein-kinase-dependent mechanism. B/oo[Pg.226]

Montero, M., Lobaton, C. D., Moreno, A., and Alvarez, J., 2002, A novel regulatory mechanism of the mitochondrial Ca2+ uniporter revealed by the p38 mitogen-activated protein kinase inhibitor SB202190, FASEB J. 16, pp. 1955-1957... 

Fig. 2 Presynaptic signaling mechanisms of ai adrenoceptor subtypes (Oia, 2B, Ofec)- Abbreviations W2abc> Pi23> adrenoceptor subtypes MAP, mitogen-activated protein kinase.

Some of the mechanisms for the rapid effects of 1713-estradiol on vascular cells were recently elucidated (33,34). It was observed that l7(3-estradiol rapidly increases proliferation of ECs and their migration through rapid upregulation of mitogen-activated protein kinases while decreasing the same events in... 

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