Molecular mechanism to maintain homeostasis in gut microbiota through protein-protein cross-linking by transglutaminase

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H04353
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Functional biochemistry
• Research Institution: Kyushu University
• Principal Investigator: Kawabata Shun-ichiro 九州大学, 理学研究院, 教授 (90183037)
• Co-Investigator(Renkei-kenkyūsha): SHIBATA Toshio 九州大学, 大学院理学研究院, 助教 (00614257)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 腸内細菌叢 / 囲食膜 / トランスグルタミナーゼ / タンパク質間の架橋 / キチン結合タンパク質 / ポリアミン / ノトバイオートハエ / 遺伝子ノックダウウン

Outline of Final Research Achievements

We obtained following findings through the project on Drosophila TG supported by this grant. TG (i) plays an important role in cuticular morphogenesis, hemolymph coagulation, and entrapment against invading pathogens, (ii) suppresses the immune deficiency pathway to enable immune tolerance against commensal bacteria through the incorporation of polyamines into the NF-κB-like transcription factor Relish as well as through the protein-protein cross-linking of Relish, (iii) forms a physical matrix in the gut through cross-linking of chitin-binding proteins, and (iv) is involved in the maintenance of homeostasis in microbiota in the gut. In addition, we found the evidence that TG-A, one of alternative splicing-derived isoforms of Drosophila TG, is secreted through an endoplasmic reticulum/Golgi-independent pathway involving exosomes and fatty acylations.

Free Research Field

生化学、節足動物の自然免疫