A link between aurora kinase and Clp1/Cdc14 regulation uncovered by the identification of a fission yeast borealin-like protein.
The chromosomal passenger complex (CPC) regulates various events in cell division. This complex is composed of a catalytic subunit, Aurora B kinase, and three nonenzymatic subunits, INCENP, Survivin, and Borealin. Together, these four subunits interdependently regulate CPC function, and they are highly conserved among eukaryotes. However, a Borealin homologue has never been characterized in the fission yeast, Schizosaccharomyces pombe. Here, we isolate a previously uncharacterized S. pombe protein through association with the Cdc14 phosphatase homologue, Clp1/Flp1, and identify it as a Borealin-like member of the CPC. Nbl1 (novel Borealin-like 1) physically associates with known CPC components, affects the kinase activity and stability of the S. pombe Aurora B homologue, Ark1, colocalizes with known CPC subunits during mitosis, and shows sequence similarity to human Borealin. Further analysis of the Clp1-Nbl1 interaction indicates that Clp1 requires CPC activity for proper accumulation at the contractile ring (CR). Consistent with this, we describe negative genetic interactions between mutant alleles of CPC and CR components. Thus, this study characterizes a fission yeast Borealin homologue and reveals a previously unrecognized connection between the CPC and the process of cytokinesis in S. pombe.
Bohnert
K Adam
KA
Howard Hughes Medical Institute, Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
Chen
Jun-Song
JS
Clifford
Dawn M
DM
Vander Kooi
Craig W
CW
Gould
Kathleen L
KL
D000595:Amino Acid Sequence; D064127:Aurora Kinases; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015825:Chromosomes, Fungal; D048749:Cytokinesis / Q000502:physiology; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D046912:Multiprotein Complexes / Q000378:metabolism; D010749:Phosphoprotein Phosphatases / Q000235:genetics / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D017433:Protein Structure, Secondary; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D017027:Protein Tyrosine Phosphatases / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012568:Schizosaccharomyces / Q000166:cytology / Q000235:genetics / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
C490157:CDCA8 protein, human; D018797:Cell Cycle Proteins; D046912:Multiprotein Complexes; C545515:Nbl1 protein, S pombe; D021122:Protein Subunits; D011993:Recombinant Fusion Proteins; D029702:Schizosaccharomyces pombe Proteins; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases; C576962:ark1 protein, S pombe; C503885:CDC14 protein, S pombe; D010749:Phosphoprotein Phosphatases; C439269:Clp1 protein, S. pombe; D017027:Protein Tyrosine Phosphatases