BAR domain proteins—a linkage between cellular membranes, signaling pathways, and the actin cytoskeleton

• Published in: Biophysical reviews 2018-12, Vol.10 (6), p.1587-1604
• Main Authors: Carman, Peter J., Dominguez, Roberto
• Format: Article
• Language: English
• Subjects: Actin; Biochemistry; Biological and Medical Physics; Biological Techniques; Biomedical and Life Sciences; Biophysics; Cell Biology; Cell membranes; Curvature; Cytoskeleton; Dimerization; Endocytosis; Life Sciences; Membrane Biology; Membrane proteins; Membranes; Muscles; Nanotechnology; Polymerization; Proteins; Review; Signaling; Structure-function relationships
• ISSN: 1867-2450; 1867-2469
• DOI: 10.1007/s12551-018-0467-7

Actin filament assembly typically occurs in association with cellular membranes. A large number of proteins sit at the interface between actin networks and membranes, playing diverse roles such as initiation of actin polymerization, modulation of membrane curvature, and signaling. Bin/Amphiphysin/Rvs (BAR) domain proteins have been implicated in all of these functions. The BAR domain family of proteins comprises a diverse group of multi-functional effectors, characterized by their modular architecture. In addition to the membrane-curvature sensing/inducing BAR domain module, which also mediates antiparallel dimerization, most contain auxiliary domains implicated in protein-protein and/or protein-membrane interactions, including SH3, PX, PH, RhoGEF, and RhoGAP domains. The shape of the BAR domain itself varies, resulting in three major subfamilies: the classical crescent-shaped BAR, the more extended and less curved F-BAR, and the inverse curvature I-BAR subfamilies. Most members of this family have been implicated in cellular functions that require dynamic remodeling of the actin cytoskeleton, such as endocytosis, organelle trafficking, cell motility, and T-tubule biogenesis in muscle cells. Here, we review the structure and function of mammalian BAR domain proteins and the many ways in which they are interconnected with the actin cytoskeleton.