title: Differential arginylation of actin isoforms: the mystery of the actin N-terminus.
abstract: Actin is one of the most abundant, essential and well studied intracellular proteins, yet its regulation in vivo is still not completely understood. One of the mysteries around actin concerns the existence of multiple actin isoforms that are extremely similar to each other except for their N-termini but have been shown in multiple studies to preferentially incorporate into different actin networks and are suggested to have different roles in vivo. The mechanisms of this actin isoform segregation are unknown. My colleagues and I recently showed that beta but not gamma actin in cultured fibroblasts undergoes N-terminal arginylation, which regulates actin polymerization and lamella formation in motile cells. Here, I propose that arginylation could be a general mechanism that regulates actin isoform segregation in vivo and participates in the formation of loose beta-actin network at the leading edge of the cell.
authors.affiliation: Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, 143 Rosenthal Building, 3800 Spruce Street, Philadelphia, PA 19104, USA.
authors.forename: Anna S
authors.initials: AS
authors.lastname: Kashina
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism / Q000648:ultrastructure; D000199:Actins / Q000737:chemistry* / Q000378:metabolism*; D000818:Animals; D001120:Arginine / Q000737:chemistry*; D002465:Cell Movement / Q000502:physiology; D003599:Cytoskeleton / Q000378:metabolism* / Q000648:ultrastructure; D006801:Humans; D011108:Polymers / Q000737:chemistry / Q000378:metabolism; D020033:Protein Isoforms / Q000737:chemistry* / Q000378:metabolism*; D017434:Protein Structure, Tertiary / Q000502:physiology; D011554:Pseudopodia / Q000737:chemistry / Q000378:metabolism
chemical_list: D000199:Actins; D011108:Polymers; D020033:Protein Isoforms; D001120:Arginine