Degradation of Newly Synthesized Polypeptides by Ribosome-Associated RACK1/c-Jun N-Terminal Kinase/Eukaryotic Elongation Factor 1A2 Complex

作者：Gandin Valentina; Gutierrez Gustavo J; Brill Laurence M; Varsano Tal; Feng Yongmei; Aza Blanc Pedro; Au Qingyan; McLaughlan Shannon; Ferreira Tiago A; Alain Tommy; Sonenberg Nahum; Topisirovic Ivan; Ronaic Ze'ev A^*

来源：Molecular and Cellular Biology, 2013, 33(13): 2510-2526.

DOI：10.1128/MCB.01362-12

Folding of newly synthesized polypeptides (NSPs) into functional proteins is a highly regulated process. Rigorous quality control ensures that NSPs attain their native fold during or shortly after completion of translation. Nonetheless, signaling pathways that govern the degradation of NSPs in mammals remain elusive. We demonstrate that the stress-induced c-Jun N-terminal kinase (JNK) is recruited to ribosomes by the receptor for activated protein C kinase 1 (RACK1). RACK1 is an integral component of the 40S ribosome and an adaptor for protein kinases. Ribosome-associated JNK phosphorylates the eukaryotic translation elongation factor 1A isoform 2 (eEF1A2) on serines 205 and 358 to promote degradation of NSPs by the proteasome. These findings establish a role for a RACK1/JNK/eEF1A2 complex in the quality control of NSPs in response to stress.

• 出版日期2013-7
• 单位河北医科大学