Absence of Gim proteins, but not GimC complex, alters stress-induced transcription

作者：Amorim Ana Fatima; Pinto Dora; Kuras Laurent; Fernandes Lisete^*

来源：Biochimica et Biophysica Acta-Gene Regulatory Mechanisms, 2017, 1860(7): 773-781.

DOI：10.1016/j.bbagrm.2017.04.005

• Transcription regulation
• Gim proteins
• Stress

Saccharomyces cerevisiae GimC (mammalian Prefoldin) is a hexameric (Gim1-6) cytoplasmic complex involved in the folding pathway of actin/tubulin. In contrast to a shared role in GimC complex, we show that absence of individual Gim proteins results in distinct stress responses. No concomitant alteration in F-actin integrity was observed. Transcription of stress responsive genes is altered in gim2 Delta, gim3 Delta and gim6 Delta mutants: TRX2 gene is induced in these mutants but with a profile diverging from type cells, whereas CTT1 and HSP26 fail to be induced. Remaining gim Delta mutants display stress transcript abundance comparable to wild type cells. No alteration in the nuclear localization of the transcriptional activators for TRX2 (Yapl) and CTT1/HSP26 (Msn2) was observed in gim2 Delta. In accordance with TRX2 induction, RNA polymerase II occupancy at TRX2 discriminates the wild type from gim2 Delta and gim6 Delta. In contrast, RNA polymerase II occupancy at CTT1 is similar in wild type and gim2 Delta, but higher in gim6 Delta. The absence of active RNA polymerase II at CTT1 in gim2 Delta, but not in wild type and girn1 Delta, explains the respective CTT1 transcript outputs. Altogether our results put forward the need of Gim2, Gim3 and Gim6 in oxidative and osmotic stress activated transcription; others Gim proteins are dispensable. Consequently, the participation of Gim proteins in activated -transcription is independent from the GimC complex.

• 出版日期2017-7
• 单位中国地震局