4F6O

Crystal structure of the yeast metacaspase Yca1

4F6O の概要

• エントリーDOI: 10.2210/pdb4f6o/pdb
• 分子名称: Metacaspase-1, 1,1-diphenylethanol (3 entities in total)
• 機能のキーワード: rossmann fold, metacaspase, hydrolase
• 由来する生物種: Saccharomyces cerevisiae (Baker's yeast)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 38809.35

構造登録者

Wong, A.H.,Yan, C.Y.,Shi, Y.G. (登録日: 2012-05-15, 公開日: 2012-07-11, 最終更新日: 2023-11-08)

主引用文献

Wong, A.H.,Yan, C.,Shi, Y.
Crystal structure of the yeast metacaspase Yca1.
J.Biol.Chem., 287:29251-29259, 2012

PubMed Abstract: Yca1, the only metacaspase in Saccharomyces cerevisiae, is thought to be a clan CD cysteine protease that includes the caspase subfamily. Although yeast is a single cell eukaryote, it can undergo a cell death process reminiscent of apoptosis. Yca1 has been reported to play an important role in the regulation of such apoptotic process. However, the structure and functional mechanism of Yca1 remain largely enigmatic. In this study, we report the crystal structure of the Yca1 metacaspase at 1.7 Å resolution, confirming a caspase-like fold. In sharp contrast to canonical caspases, however, Yca1 exists as a monomer both in solution and in the crystals. Canonical caspase contains six β-strands, with strand β6 pairing up with β6 of another caspase molecule to form a homodimerization interface. In Yca1, an extra pair of antiparallel β-strands forms a continuous β-sheet with the six caspase-common β-strands, blocking potential dimerization. Yca1 was reported to undergo autocatalytic processing in yeast; overexpression in bacteria also led to autoprocessing of Yca1 into two fragments. Unexpectedly, we found that both the autocatalytic processing and the proteolytic activity of Yca1 are greatly facilitated by the presence of calcium (Ca(2+)), but not other divalent cations. Our structural and biochemical characterization identifies Yca1 as a Ca(2+)-activated cysteine protease that may cleave specific substrates during stress response in yeast.

PubMed: 22761449
DOI: 10.1074/jbc.M112.381806

実験手法

X-RAY DIFFRACTION (1.681 Å)