title: Schizosaccharomyces pombe Arc3 is a conserved subunit of the Arp2/3 complex required for polarity, actin organization, and endocytosis.
abstract: We characterized the Schizosaccharomyces pombe arc3 gene, whose product shares sequence homology with that of the budding yeast ARC18 and human ARPC3/p21 subunits of the Arp2/3 complex. Our data showed that Arc3p co-localizes with F-actin patches at the cell ends, but not with F-actin cables or the equatorial actin ring, and binds other subunits of the Arp2/3 complex. Gene deletion analysis showed that arc3 is essential for viability. When arc3 expression was repressed, F-actin patches became dispersed throughout the cell with greatly reduced mobility. Furthermore, in arc3-repressed cells, endocytosis was also inhibited. Human ARPC3 rescued the viability of the Sz. pombe arc3 null mutant; in addition, ARPC3 also localized to F-actin patches in human cells. These data suggest that Arc3p is an evolutionarily conserved subunit of the Arp2/3 complex required for proper F-actin organization and efficient endocytosis.
authors: Department of Molecular and Cellular Biology and Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA.
authors: Rodrigo
authors: R
authors: Cabrera
authors: Jinfeng
authors: J
authors: Suo
authors: Evelin
authors: E
authors: Young
authors: Eric C
authors: EC
authors: Chang
mesh_terms: D051376:Actin-Related Protein 2-3 Complex / Q000737:chemistry* / Q000378:metabolism*; D000199:Actins / Q000378:metabolism*; D004705:Endocytosis; D005656:Fungal Proteins / Q000302:isolation & purification* / Q000378:metabolism*; D017353:Gene Deletion; D020043:Genes, Essential; D005800:Genes, Fungal; D005816:Genetic Complementation Test; D050296:Microbial Viability; D012568:Schizosaccharomyces / Q000378:metabolism / Q000502:physiology*
chemical_list: D051376:Actin-Related Protein 2-3 Complex; D000199:Actins; D005656:Fungal Proteins