4A4K

Crystal structure of the S. cerevisiae Ski2 insertion domain

4A4K の概要

• エントリーDOI: 10.2210/pdb4a4k/pdb
• 分子名称: ANTIVIRAL HELICASE SKI2, ZINC ION (2 entities in total)
• 機能のキーワード: dexh helicase, hydrolase, rna degradation, exosome
• 由来する生物種: SACCHAROMYCES CEREVISIAE (BAKER'S YEAST)
• タンパク質・核酸の鎖数: 5
• 化学式量合計: 148876.21

構造登録者

Halbach, F.,Rode, M.,Conti, E. (登録日: 2011-10-17, 公開日: 2011-12-21, 最終更新日: 2024-05-08)

主引用文献

Halbach, F.,Rode, M.,Conti, E.
The Crystal Structure of S. Cerevisiae Ski2, a Dexh Helicase Associated with the Cytoplasmic Functions of the Exosome.
RNA, 18:124-, 2012

PubMed Abstract: Ski2 is a cytoplasmic RNA helicase that functions together with the exosome in the turnover and quality control of mRNAs. Ski2 is conserved in eukaryotes and is related to the helicase Mtr4, a cofactor of the nuclear exosome involved in the processing and quality control of a variety of structured RNAs. We have determined the 2.4 Å resolution crystal structure of the 113 kDa helicase region of Saccharomyces cerevisiae Ski2. The structure shows that Ski2 has an overall architecture similar to that of Mtr4, with a core DExH region and an extended insertion domain. The insertion is not required for the formation of the Ski2-Ski3-Ski8 complex, but is instead an RNA-binding domain. While this is reminiscent of the Mtr4 insertion, there are specific structural and biochemical differences between the two helicases. The insertion of yeast Mtr4 consists of a β-barrel domain that is flexibly attached to a helical stalk, contains a KOW signature motif, and binds in vitro-transcribed tRNA(i)(Met), but not single-stranded RNA. The β-barrel domain of yeast Ski2 does not contain a KOW motif and is tightly packed against the helical stalk, forming a single structural unit maintained by a zinc-binding site. Biochemically, the Ski2 insertion has broad substrate specificity, binding both single-stranded and double-stranded RNAs. We speculate that the Ski2 and Mtr4 insertion domains have evolved with different properties tailored to the type of transcripts that are the substrates of the cytoplasmic and nuclear exosome.

PubMed: 22114319
DOI: 10.1261/RNA.029553.111

実験手法

X-RAY DIFFRACTION (3.25 Å)