Roles of the MAP Kinase Cascade in Vertebrates

摘要: Publisher Summary This chapter focuses on the roles of MAP kinase cascade in mammalian cultured cells and Xenopus systems. One most outstanding characteristics kinases is their activation mechanism. Activation requires phos- phorylation both threonine tyrosine residues sequence “TEY” located between subdomains VII VIII. commonly activated by a large number extracellular stimuli supposed to play key role various intracellular signal transduction pathways because can phosphorylate many target substrates vitro . However, few have been shown be for vivo In PC12 cells, NGF epidermal growth factor (EGF) activate 43-kDa (ERK1) 41-kDa (ERK2). The EGF-induced transient, whereas NGF-induced sustained accompanied nuclear translocation kinases. Fully grown Xelzopus oocytes are naturally arrested at prophase meiosis I. Progesterone releases this arrest induces progression through meiosis. activities MAPKK elevated about same time as MPF during progesterone-induced oocyte maturation, suggesting possibility positive feedback loop MPF. stimuli. Evidence accumulating involvement wide variety cellular responses including differentiation proliferation fibroblasts, metaphase arrest, mesoderm induction summarized chapter.