Ras-Gefs and Ras Gaps

摘要: Ras proteins (H-, N-, and K-Ras) are critical components of signal transduction pathways leading from cell-surface receptors to the control cell proliferation, differentiation or death. Normal exist in equilibrium between an active (Ras-GTP) inactive (Ras-GDP) state. Once activated, stimulates a multitude downstream signaling pathways, but different data about location plasma membrane subdomains new roles for some docking/scaffold proteins, point specificities proteins. Studies with knockout mice strains have revealed that Kras (but not Nras Hras) is necessary sufficient development animals adult stage. Although possess intrinsic GTPase GDP/GTP exchange activities, they too low account rapid transient cycling occurs during mitogenic stimulation. Then, function requires regulatory rate. These include activating (Ras-GAPs), which stimulate hydrolysis bound GTP GDP, guanine nucleotide factor (Ras-GEFs), promote replacement GDP GTP. We undertook this review analyze current understanding mammalian Ras-GAPs Ras-GEFs functions, focusing on possible physiological each Ras-GAP/Ras-GEF family member. Furthermore, we analyzed mechanisms Rac activation due covalent-interaction hydrophobic molecules as NO cyclopentenone prostaglandins