Nanoscience Seminar Series with Cheng-Han Yu, The University of Hong Kong

Title: Matrix microenvironment modulates force-dependent adhesion signaling of integrin receptors

Abstract: Matrix-integrin activation triggers cell adhesion. Force development at integrins can differentially regulate adaptor protein recruitment, and micro-partitioned RGD-membrane provides a unique substrate to study force-dependent signal transduction. Previously, we have used RGD-membrane to investigate initial activation of integrin clustering and podosome formation. Here we report that clathrin-associated adaptor protein Dab2 progressively binds to integrin-beta3 after 20-min of cell adhesion on mobile RGD-membrane. When a single cell adheres on the substrate with both mobile and immobile ligands, Dab2 is preferentially recruited to integrin-beta3 at mobile RGD regions. Intriguingly, Dab2 is mutually excluded with other integrin-binding proteins, including talin, kindlin, focal adhesion kinase, paxillin, and vinculin. Point mutations of tyrosine residues of integrin-beta3 block Dab2 binding. Increase cellular contractility by RhoA-Q63L and phospho-mimic MRLC mutant impedes Dab2 recruitment on mobile RGD membrane. More importantly, decrease myosin-II activity by blebbistatin promotes Dab2 binding to integrin-beta3 on immobile matrices. As a result, Dab2 recruits clathrin- mediated endocytic machinery and results in RGD-integrin endocytosis. We propose that absence of traction force causes recruitment of Dab2/clathrin and endocytosis of integrin-beta3.

  • Start Date: 5/25/2017
  • End Date: 5/25/2017
  • Time: 12:00 PM - 1:00 PM
  • College: CUNY Advanced Science Research Center
  • Address: 85 St. Nicholas Terrace, Manhattan
  • Building: CUNY Advanced Science Research Center
  • Room: Seminar Room
  • Phone: 212-413-3382
  • Website:
  • Admission: Free

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