The SH3 domains of two PCH family members cooperate in assembly of the Schizosaccharomyces pombe contractile ring.
Schizosaccharomyces pombe cdc15 homology (PCH) family members participate in many cellular processes by bridging the plasma membrane and cytoskeleton. Their F-BAR domains bind and curve membranes, whereas other domains, typically SH3 domains, are expected to provide cytoskeletal links. We tested this prevailing model of functional division in the founding member of the family, Cdc15, which is essential for cytokinesis in S. pombe, and in the related PCH protein, Imp2. We find that the distinct functions of Imp2 and Cdc15 are SH3 domain independent. However, the Cdc15 and Imp2 SH3 domains share an essential role in recruiting proteins to the contractile ring, including Pxl1 and Fic1. Together, Pxl1 and Fic1, a previously uncharacterized C2 domain protein, add structural integrity to the contractile ring and prevent it from fragmenting during division. Our data indicate that the F-BAR proteins Cdc15 and Imp2 contribute to a single biological process with both distinct and overlapping functions.
Roberts-Galbraith
Rachel H
RH
Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.
Chen
Jun-Song
JS
Wang
Jianqiu
J
Gould
Kathleen L
KL
D001665:Binding Sites; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D048749:Cytokinesis / Q000235:genetics / Q000502:physiology*; D003598:Cytoskeletal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D019204:GTP-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D017353:Gene Deletion; D049452:Green Fluorescent Proteins / Q000032:analysis; D025941:Protein Interaction Mapping; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000032:analysis; D012568:Schizosaccharomyces / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D029702:Schizosaccharomyces pombe Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
C082279:CDC15 protein; D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; C535065:Fic1 protein, S pombe; C535064:IMP2 protein, S pombe; C533048:Pxl1 protein, S pombe; D011993:Recombinant Fusion Proteins; D029702:Schizosaccharomyces pombe Proteins; D049452:Green Fluorescent Proteins; D019204:GTP-Binding Proteins