Studies on molecular mechanism of paracellular pathway

• Project/Area Number: 26440029
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Structural biochemistry
• Research Institution: Osaka University
• Principal Investigator: Aoyama Hiroshi 大阪大学, 薬学研究科, 准教授 (60291910)
• Co-Investigator(Renkei-kenkyūsha): KONDOH Masuo 大阪大学, 大学院薬学研究科, 准教授 (50309697)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥5,070,000 (Direct Cost: ¥3,900,000、Indirect Cost: ¥1,170,000); Fiscal Year 2016: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2015: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2014: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: Ｘ線結晶構造解析 / 膜タンパク質 / 国際情報交換

Outline of Final Research Achievements

We performed the following studies on claudin, which plays a barrier function between cells, and connexin, which is responsible for substrate transport between cells. Two CL binders wirh high affinity for CL were created from mutant variant screening of the C-terminal domain of Clostridium perfringens enterotoxin, which is known as a inhibitory protein in the paracellular route.　These X-ray structures revealed strucrutal changes contributing to the stability of complex formation with CL.　For structural activity correlation was analyzed for tisse-specifically expressed Cx by the combination of dual patch clamp and homology structure modelling.

Research Products

• [Int'l Joint Research] University of Western Ontario(Canada)
• [Int'l Joint Research] University of Western Ontario(Canada)
• [Journal Article] Engineered Cx26 variants established functional heterotypic Cx26/Cx43 and Cx26/Cx40 gap junction channels (2016)
  • Author(s): Levent B. Karademir, Hiroshi Aoyama, Benny Yue, Honghong Chen, Donglin
  • Journal Title: Biochemical Journal Volume: 473 Issue: 10 Pages: 1391-1403
  • DOI: 10.1042/bcj20160200
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Engineered Cx40 variants increased docking and function of heterotypic Cx40/Cx43 gap junction channels (2016)
  • Author(s): Arjewan Jassim, Hiroshi Aoyama ,Willy G. Ye, Honghong Chen, Donglin Bai
  • Journal Title: Journal of Molecular and Cellular Cardiology Volume: 90 Pages: 11-20
  • DOI: 10.1016/j.yjmcc.2015.11.026
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] The first extracellular domain plays an important role in unitary channel conductance of Cx50 gap junction channels (2015)
  • Author(s): Xiaoling Tong, Hiroshi Aoyama, Swathy Sudhakar, Honghong Chen, Brian H. Shilton, Donglin Bai
  • Journal Title: PLOS ONE Volume: 10(12) Issue: 12 Pages: e0143876-e0143876
  • DOI: 10.1371/journal.pone.0143876
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Charge at the 46th residue of connexin 50 is crucial for the gap-junction unitary conductance and transjunctional voltage-depending gating (2014)
  • Author(s): Xiaoling Tong, Hiroshi Aoyama, Tomitake Tsukihara, Donglin Bai
  • Journal Title: The Journal of Physiology Volume: 592 Issue: 23 Pages: 5187-5202
  • DOI: 10.1113/jphysiol.2014.280636
  • Peer Reviewed / Acknowledgement Compliant
• [Presentation] ENGINEERED CX40 VARIANTS SHOWED HETEROTYPIC COLOCALIZATION AND INCREASED GAP JUNCTIONAL COUPLING WITH CX43 (2016)
  • Author(s): Arjewan Jassim, Hiroshi Aoyama, Willy G. Ye, Honghong Chen, Donglin Bai
  • Organizer: Biophysical Society 60th Annual Meeting
  • Place of Presentation: Los Angeles, USA
  • Year and Date: 2016-02-27
  • Int'l Joint Research
• [Presentation] The first extracellular domain plays an important role in single channel conductance of Cx50 gap junction channels (2015)
  • Author(s): Tong, Xiaoling., Aoyama, Hiroshi., Sudhakar, Swathy., Chen, Honghong., Bai, Donglin
  • Organizer: International Gap Junction Conference
  • Place of Presentation: Chile
  • Year and Date: 2015-04-01
  • Int'l Joint Research
• [Presentation] The residues in the first extracellular domain play an important role in transjunctional-voltage dependent gating and unitary channel conductance of Cx50 gap junctional channels (2015)
  • Author(s): Xioling Tong, Hiroshi Aoyama, Swathy Sudhakar, Honghong Chen, Donglin Bai
  • Organizer: Biophysical Society 59th Annual Meeting
  • Place of Presentation: Baltimore, Maryland, USA
  • Year and Date: 2015-02-07 – 2015-02-11
• [Presentation] Charge at the 46th residue of Cx50 is critical for the gap junctional unitary conductance and transjunctional voltage-dependent gating (2014)
  • Author(s): Xioling Tong, Hiroshi Aoyama, Tomitake Tsukihara, Donglin Bai
  • Organizer: 2014 International Biophysics Congress
  • Place of Presentation: Brisbane, Australia
  • Year and Date: 2014-08-03 – 2014-08-07