Identification of Elongin A target genes and clarification of the mechanisms governing conversion of the Elongin complex from its elongation factor to its ubiquitin ligase form

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K08279
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: General medical chemistry
• Research Institution: Kochi University
• Principal Investigator: Aso Teijiro 高知大学, 教育研究部医療学系基礎医学部門, 教授 (20291289)
• Co-Investigator(Renkei-kenkyūsha): KITAJIMA Shigetaka 東京医科歯科大学, 難治疾患研究所, 教授 (30186241)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: Elongin / CSB / ユビキチンリガーゼ / 転写伸長 / RNAポリメラーゼII / DNA傷害 / ストレス / 遺伝子発現

Outline of Final Research Achievements

Elongin A (EloA) performs dual functions as the transcriptionally active subunit of RNA polymerase II (Pol II) elongation factor Elongin and as the substrate recognition subunit of an ubiquitin ligase (E3) that ubiquitylates Pol II in response to DNA damage. In this study, we first identified Hox genes as the targets of elongation factor EloA. We also investigated the mechanisms governing conversion of the Elongin complex from its elongation factor to its E3 form. Assembly of EloA into the E3 was strongly induced by DNA-damaging agents; and α-amanitin, a drug that induces Pol II stalling; and by other various stimuli. In addition, we demonstrated (i) that EloA and the E3 subunit Cul5 associate in cells with the Cockayne syndrome B (CSB) protein, (ii) that this interaction was also induced by DNA-damaging agents and α-amanitin, and (iii) that CSB protein promotes stable recruitment of the EloA-E3 to sites of DNA damage.

Free Research Field

分子生物学