Many faces of Ras activation.

摘要: Ras proteins were originally identified as the products of oncogenes capable inducing cell transformation. Over last twenty-five years they have been studied in great detail because mutant are associated with many types human cancer. Wild type play a central role regulation proliferation and differentiation various types. They alternate between an active GTP-bound state inactive GDP-bound state. Their activation is catalysed by specialized group enzymes known guanine nucleotide exchange factors (GEFs). To date, four subfamilies GEF molecules identified. Although all them able to activate Ras, their structure, tissue expression significantly diverse. In this review we will summarize mechanisms which these Ras.