Analysis of transcriptional regulation of villin in liver

• Project/Area Number: 16K09207
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Legal medicine
• Research Institution: Kyoto University
• Principal Investigator: Ozeki Munetaka 京都大学, 医学研究科, 助教 (80549618)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000); Fiscal Year 2018: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2017: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2016: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: 肝臓 / ビリン / リトコール酸 / 転写 / villin / 転写制御 / 胆汁鬱滞

Outline of Final Research Achievements

To investigate the transcriptional regulation of villin in HepG2 human hepatocarcinoma cells, Luciferase reporter assay was carried out using villin promoter fragments. Transcription factors SRF and TBP transcribed villin via TATA Box/CArG Box locates around -60 bp on villin promoter. These transcriptional factors reduced their transcriptional activity under lithocholic acid stimulation in HepG2 cells. Villin mRNA expression was decreased by SRF knockdown using siRNA, and increased by TBP knockdown. These result suggest that villin transcriptional regulation by SRF and TBP are prevented by lithocholic acid under cholestasis.

Academic Significance and Societal Importance of the Research Achievements

本研究において、リトコール酸刺激下で転写因子SRFおよびTBPの転写活性が低下することが新たに明らかとなった。SRFは細胞形態の維持に必要な多くの遺伝子の発現を司り、TBPは基礎転写に重要な転写因子として知られている。胆汁鬱滞下でこれらの転写因子がリトコール酸の影響を受ける可能性が示唆されたことで、胆汁鬱滞性肝疾患における遺伝子発現調節を理解するのに役立つとともに、新規の治療法の開発につながる可能性が見出された。

Research Products

• [Journal Article] Prevention of Cell Growth by Suppression of Villin Expression in Lithocholic Acid-Stimulated HepG2 Cells (2018)
  • Author(s): Ozeki Munetaka、Aini Wulamujiang、Miyagawa-Hayashino Aya、Tamaki Keiji
  • Journal Title: Journal of Histochemistry & Cytochemistry Volume: 67 Issue: 2 Pages: 129-141
  • DOI: 10.1369/0022155418804507
  • Peer Reviewed
• [Presentation] Suppression of villin expression and cell growth arrest by lithocholic acid in HepG2 human hepatocarcinoma cells (2018)
  • Author(s): Munetaka Ozeki, Leila Jemail, Hirozo Minami, Hitoshi Abiru, Keiji Tamaki
  • Organizer: 24th Congress of the International Academy of Legal Medicine/第102次日本法医学会学術集会 合同開催
  • Int'l Joint Research
• [Presentation] ヒト肝癌細胞株HepG2におけるリトコール酸によるビリン発現抑制に関する研究 (2018)
  • Author(s): 尾関宗孝、玉木敬二
  • Organizer: 第91回日本生化学会大会
• [Presentation] リトコール酸によるvillinの発現抑制作用に関する研究 (2017)
  • Author(s): 尾関宗孝、玉木敬二
  • Organizer: 肝細胞研究会