北海道大学 大学院理学研究院 化学部門

生物化学研究室

講演者

Prof. James G. Omichinski
（Department of Biochemistry and Molecular Medicine, Université de Montréal）

日時

平成27年3月24日（火）　13:45-14：30

場所

北海道大学理学部　6号館　2階04-2室＜多目的演習室＞

概要

Rift Valley fever virus (RVFV) is a single-stranded RNA virus and the causative agent of the zoonotic vector-borne disease Rift Valley fever. Although RVFV is considered a tropical virus, like other tropical hemorrhagic fever viruses including Ebola, there is increasing concern that it will become more prevalent in other regions of the world due to vector migration as a result of rising global temperatures. A key component of RVFV virulence is its ability to form nuclear filaments through interactions between the viral non-structural protein NSs and the host general transcription factor TFIIH. We have identified an interaction between a ΩXaV motif in NSs and the p62 subunit of TFIIH. This motif in NSs is similar to ΩXaV motifs found in nucleotide excision repair (NER) factors Rad2 and Rad4 and the general transcription factor IIE known to interact with p62. Structural and biophysical studies demonstrate that NSs binds to p62 in a similar manner as these other DNA repair and transcription factors. Functional studies in RVFV-infected cells show that the ΩXaV motif is required for both nuclear filament formation and degradation of p62. Consistent with the fact that the RFVF can be distinguished from other Bunyaviridae-family viruses due to its ability to form nuclear filaments in infected cells, the motif is absent in the NSs proteins of other Bunyaviridae-family viruses. Taken together, our studies demonstrate that p62 binding to NSs through the ΩXaV motif is essential for degrading p62, forming nuclear filaments and enhancing RVFV virulence. I will discuss how the RVFV has incorporated a simple motif into the NSs protein that enables it to functionally mimic host cell proteins that bind the p62 subunit of TFIIH.

主催

Ambitious物質科学セミナー

共催

生命分子化学セミナー

連絡先

北海道大学 大学院理学研究院 化学部門
生物化学研究室
坂口 和靖
TEL: 011-706-2698