Mechanisms of protein disulfide bond formation in the ER of mammalian cells

2014 Fiscal Year Final Research Report

• Project/Area Number: 24580141
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Applied biochemistry
• Research Institution: Tohoku University (2013-2014); Nara Institute of Science and Technology (2012)
• Principal Investigator: KADOKURA Hiroshi 東北大学, 多元物質科学研究所, 准教授 (70224558)
• Co-Investigator(Renkei-kenkyūsha): SAITO Michiko 奈良先端科学技術大学院大学, バイオサイエンス研究科, 助教 (40379558) ; KOHNO Kenji 奈良先端科学技術大学院大学, バイオサイエンス研究科, 教授 (50142005)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 物質生産 / ジスルフィド結合 / 立体構造形成 / 分泌タンパク質 / 小胞体 / 哺乳動物

Outline of Final Research Achievements

Formation of disulfide bonds is a crucial step in the folding of a number of proteins that go through the secretory pathway. They include proteins with industrial importance such as insulin. The ER of mammalian cells harbors twenty enzymes that belong to thioredoxin-superfamily members (they are also called thioredoxin-like proteins). These enzymes are implicated in the formation of protein disulfide bonds. However, the physiological function of each enzyme is unclear, due to the lack of information on its substrates. To gain insights into the role of JPDI, one of the enzymes, we successfully identified the potential substrates of this enzyme from a mouse tissue. Furthermore, we were able to identify four of thioredoxin-superfamily members that interacted with proinsulin (a precursor of insulin) via formation of an intermolecular disulfide bond. These findings provide insights into the mechanisms of folding of secretory proteins in mammalian cells.

Free Research Field

農学