The structure of human ADCY9 and Gs alpha subunit to explore therapeutic agents for congenital nephrogenic diabetes insipidus

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K17245
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 53040:Nephrology-related
• Research Institution: Tokyo Medical and Dental University
• Principal Investigator: Nomura Risa 東京医科歯科大学, 高等研究院, 特任助教 (70868124)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: アデニル酸シクラーぜ / ADCY 9 / クライオ電子顕微鏡 / cryo-EM / 先天性腎性尿崩症 / NDI

Outline of Final Research Achievements

In this study, we attempted to analyze the structure of adenylate cyclase (ADCY), which acts in conjunction with vasopressin receptor (V2R) in renal collecting duct principal cells, in order to search for a therapeutic agent for congenital nephrogenic diabetes insipidus (NDI). Human ADCY 3, 6, and 9 are conjugated with V2R, and based on past research, we specifically purified the expression of ADCY 6 and 9 and analyzed them using cryo-electron microscopy (cryo-EM). As a result, we created consensus sequences for ADCY6 in nine types of mammals other than humans and in 200 types of vertebrates, but the expression status was unstable and analysis was difficult. We have successfully expressed and purified human ADCY 9 and are currently preparing to publish it in a paper.

Free Research Field

細胞構造生理学

Academic Significance and Societal Importance of the Research Achievements

ADCYは10種類あり、広く生体内に発現し、Gタンパク質共役受容体と共役し調整をしている。bovinenのADCY 9,8,5の構造が報告されているが、ADCYの発現精製自体が困難であることも多く、それゆえ既報も分解能が3.5Å前後と側鎖の評価などが十分ではない。ADCYは12本の膜貫通ドメイン(TM)と酵素活性部位（C1 ,C2)、TMとC1 ,C2を繋ぐドメイン（HD)があるが、Gタンパク質やATP の結合時のTMやHDの機能や酵素活性時における構造変化などが十分にはわかっていない。本研究はヒトADCY９においてより分解能のよい構造解析をすることで上記を明らかにする足がけとなる研究である。