Elucidation of pancreatic and intestinal dysbiosis using human disease iPS cells and its application to regenerative medicine

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K06970
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 49030:Experimental pathology-related
• Research Institution: Kyoto University
• Principal Investigator: Fujikura Junji 京都大学, 医学研究科, 助教 (70378743)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 膵 / 腸管 / RFX6 / iPS細胞 / 発生 / Mitchell-Riley症候群 / 糖尿病 / インクレチン

Outline of Final Research Achievements

RFX6 is the causative gene of Mitchell-Riley syndrome, which shows pancreatic hypoplasia and intestinal obstruction and develops neonatal diabetes. In this study, RFX6 heterozygous and homozygous GFP knock-in/knock-out hiPSCs were established and induced to differentiate into the endoderm lineage. RFX6 expression increased rapidly in the primitive intestinal tract, followed by RFX6 loss, which reduced expression of PDX1 and CDX2, regulatory genes of the posterior foregut and mid-hindgut, respectively. Using cap analysis, we found RFX6-binding X-box motifs and the motif sequences in the enhancer regions of PDX1 and CDX2 bind RFX6 in vitro. In Mitchell-Riley syndrome, defects in early endodermal patterning were shown to be etiologic.

Free Research Field

内分泌・代謝

Academic Significance and Societal Importance of the Research Achievements

RFX6はMitchell-Riley症候群だけでなく腸管内分泌や膵β細胞の分化や機能に関わっている。今回RFX6欠損hiPSCを内胚葉分化系に適用し、病態モデル作成に成功した。ヒト胎児で不可能な網羅的解析を行いRFX6の結合する新たなmotifを発見しえた。今後RFX6が制御する遺伝子群の検討により各種内胚葉系疾患の病態解明が可能となる。また、RFX6発現をGFP蛍光で示す本細胞を用いてRFX6を制御する物質を探索し、RFX6陽性細胞由来である膵・腸管内分泌細胞への分化促進因子をスクリーニングし、vitroでの膵・腸管細胞分化を実現させることにより膵腸管疾患再生医療への展開が可能となる。