A 32 kDa protein--whose phosphorylation correlates with oncogenic Ras-induced cell cycle arrest in activated Xenopus egg extracts--is identified as ribosomal protein S6.

摘要: Oncogenic Ras induces cell-cycle arrest in mammalian cells and fertilized Xenopus eggs. How oncogenic remains unclear. We previously showed that activated egg extracts (cycling extracts) the induced correlates with hyperphosphorylation of a 32 kDa protein. However, identity protein was not known. By using sucrose density-gradient centrifugation, Triton X-100-acetic acid-urea (TAU)-gel electrophoresis, composite agarose-polyacrylamide gel electrophoresis (CAPAGE), SDS-PAGE, partial tryptic peptide sequence analysis, has now been identified as S6, 40S subunit ribosomal Hence, our results indicate Ras-induced is correlated suggesting phosphorylation S6 plays an important role arrest. It shown conditional deletion gene encoding prevents proliferation, demonstrating importance cell proliferation. The exact proliferation implicated regulation synthesis. Thus, are consistent concept to influence synthesis, thereby contributing In addition, also demonstrate suitable for separation large molecular complexes.