Send to

Choose Destination
Structure. 2003 Jun;11(6):615-25.

Structural and functional analysis of the actin binding domain of plectin suggests alternative mechanisms for binding to F-actin and integrin beta4.

Author information

Program on Cell Adhesion, The Burnham Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.


Plectin is a widely expressed cytoskeletal linker. Here we report the crystal structure of the actin binding domain of plectin and show that this region is sufficient for interaction with F-actin or the cytoplasmic region of integrin alpha6beta4. The structure is formed by two calponin homology domains arranged in a closed conformation. We show that binding to F-actin induces a conformational change in plectin that is inhibited by an engineered interdomain disulfide bridge. A two-step induced fit mechanism involving binding and subsequent domain rearrangement is proposed. In contrast, interaction with integrin alpha6beta4 occurs in a closed conformation. Competitive binding of plectin to F-actin and integrin alpha6beta4 may rely on the observed alternative binding mechanisms and involve both allosteric and steric factors.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center