Regulation of nuclear protein functions by N-acetylglucosamine modification

2014 Fiscal Year Final Research Report

• Project/Area Number: 24390015
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Biological pharmacy
• Research Institution: The University of Tokyo
• Principal Investigator: YAMAMOTO Kazuo 東京大学, 新領域創成科学研究科, 教授 (20174782)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: Nーアセチルグルコサミン修飾 / 核内タンパク質 / レクチン / イメージング

Outline of Final Research Achievements

O-GlcNAcylation of nuclear proteins is a unique reaction in several points of view. O-GlcNAcyation levels are modulated in response to cellular signaling and affect protein localization, activity and stability. We screened engineered lectins to monitor O-GlcNAc modification using mammalian cell surface display from randomized lectin library. Furthermore, we expressed a soluble form of β-N-acetylgalactosaminyltransferase in the nucleus to change O-GlcNAc to GalNAc-GlcNAc. A novel lectin specific for GalNAc-GlcNAc was purified from Wisteria japonica seeds. Using these lectins as a probe, we identified more than 80 kinds of O-GlcNAc-modified proteins including 10 kinds of novel proteins from the nuclear and cytosolic fractions. O-GlcNAc-moidifed peptides were purified by lectin affinity chromatography and identified O-GlcNAc-modified residues by mass spectrometry. A lectin-GFP was expressed in the cytoplasm for monitoring O-GlcNAcylation in a live cell during cell activation.

Free Research Field

糖鎖生物学