Dynamic visualization of α-catenin reveals rapid, reversible conformation switching between tension states

Tae Jin Kim, Shuai Zheng, Jie Sun, Ismaeel Muhamed, Jun Wu, Lei Lei, Xinyu Kong, Deborah E. Leckband, Yingxiao Wang

Research output: Contribution to journalArticle

Abstract

The cytosolic protein α-catenin is a postulated force transducer at cadherin complexes [1]. The demonstration of force activation, identification of consequent downstream events in live cells, and development of tools to study these dynamic processes in living cells are central to elucidating the role of α-catenin in cellular mechanics and tissue function [2-10]. Here we demonstrate that α-catenin is a force-activatable mechanotransducer at cell-cell junctions by using an engineered α-catenin conformation sensor based on fluorescence resonance energy transfer (FRET). This sensor reconstitutes α-catenin-dependent functions in α-catenin-depleted cells and recapitulates the behavior of the endogenous protein. Dynamic imaging of cells expressing the sensor demonstrated that α-catenin undergoes immediate, reversible conformation switching in direct response to different mechanical perturbations of cadherin adhesions. Combined magnetic twisting cytometry with dynamic FRET imaging [11] revealed rapid, local conformation switching upon the mechanical stimulation of specific cadherin bonds. At acutely stretched cell-cell junctions, the immediate, reversible conformation change further reveals that α-catenin behaves like an elastic spring in series with cadherin and actin. The force-dependent recruitment of vinculin - a principal α-catenin effector - to junctions requires the vinculin binding site of the α-catenin sensor [1, 12-16]. In cells, the relative rates of force-dependent α-catenin conformation switching and vinculin recruitment reveal that α-catenin activation and vinculin recruitment occur sequentially, rather than in a concerted process, with vinculin accumulation being significantly slower. This engineered α-catenin sensor revealed that α-catenin is a reversible, stretch-activatable sensor that mechanically links cadherin complexes and actin and is an indispensable player in cadherin-specific mechanotransduction at intercellular junctions.

Original languageEnglish (US)
Pages (from-to)218-224
Number of pages7
JournalCurrent Biology
Volume25
Issue number2
DOIs
StatePublished - Jan 19 2015

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Agricultural and Biological Sciences(all)

Fingerprint Dive into the research topics of 'Dynamic visualization of α-catenin reveals rapid, reversible conformation switching between tension states'. Together they form a unique fingerprint.

  • Cite this