title: The Arp2/3 complex: a central regulator of the actin cytoskeleton.
abstract: In recent years the Arp2/3 complex has emerged as a central regulator of actin dynamics, assembling and cross-linking actin filaments to produce a diverse array of cellular structures. Here I discuss our current state of knowledge about this actin-remodelling machine. The predicted structure of the Arp2/3 complex can be directly correlated with its ability to nucleate, cap and cross-link actin filaments. A growing family of Arp2/3 complex activators such as the WASP family, type I myosins, and the newly identified activators cortactin and Abplp tightly regulate this activity within the cell. Localised activation of the Arp2/3 complex produces structures such as lamellipodia or actin patches via a process termed dendritic nucleation. Furthermore, several pathogenic microorganisms have evolved strategies to 'hijack' the Arp2/3 complex to their own advantage. Finally, I discuss some of the questions which remain unanswered about this fascinating complex.
authors.affiliation: School of Biosciences, University of Birmingham, Edgbaston, United Kingdom. r.c.may@bham.ac.uk
authors.forename: R C
authors.initials: RC
authors.lastname: May
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism*; D051377:Actin-Related Protein 2; D051378:Actin-Related Protein 3; D000199:Actins / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism; D021961:Cell Membrane Structures / Q000378:metabolism; D003598:Cytoskeletal Proteins; D005656:Fungal Proteins / Q000378:metabolism; D006801:Humans; D046911:Macromolecular Substances; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D010940:Plant Proteins / Q000378:metabolism; D020033:Protein Isoforms; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D051316:Wiskott-Aldrich Syndrome Protein
chemical_list: C495926:ACTR2 protein, human; C495928:ACTR3 protein, human; D051377:Actin-Related Protein 2; D051378:Actin-Related Protein 3; D000199:Actins; D001426:Bacterial Proteins; D003598:Cytoskeletal Proteins; D005656:Fungal Proteins; D046911:Macromolecular Substances; D010940:Plant Proteins; D020033:Protein Isoforms; D011506:Proteins; C495767:WAS protein, human; D051316:Wiskott-Aldrich Syndrome Protein