title: Co-regulation proteomics reveals substrates and mechanisms of APC/C-dependent degradation.
abstract: Using multiplexed quantitative proteomics, we analyzed cell cycle-dependent changes of the human proteome. We identified >4,400 proteins, each with a six-point abundance profile across the cell cycle. Hypothesizing that proteins with similar abundance profiles are co-regulated, we clustered the proteins with abundance profiles most similar to known Anaphase-Promoting Complex/Cyclosome (APC/C) substrates to identify additional putative APC/C substrates. This protein profile similarity screening (PPSS) analysis resulted in a shortlist enriched in kinases and kinesins. Biochemical studies on the kinesins confirmed KIFC1, KIF18A, KIF2C, and KIF4A as APC/C substrates. Furthermore, we showed that the APC/C(CDH1)-dependent degradation of KIFC1 regulates the bipolar spindle formation and proper cell division. A targeted quantitative proteomics experiment showed that KIFC1 degradation is modulated by a stabilizing CDK1-dependent phosphorylation site within the degradation motif of KIFC1. The regulation of KIFC1 (de-)phosphorylation and degradation provides insights into the fidelity and proper ordering of substrate degradation by the APC/C during mitosis.
authors: Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA.
authors: Sasha A
authors: SA
authors: Singh
authors: Dominic
authors: D
authors: Winter
authors: Marc
authors: M
authors: Kirchner
authors: Ruchi
authors: R
authors: Chauhan
authors: Saima
authors: S
authors: Ahmed
authors: Nurhan
authors: N
authors: Ozlu
authors: Amit
authors: A
authors: Tzur
authors: Judith A
authors: JA
authors: Steen
authors: Hanno
authors: H
authors: Steen
mesh_terms: D000595:Amino Acid Sequence; D064173:Anaphase-Promoting Complex-Cyclosome / Q000378:metabolism*; D002453:Cell Cycle; D006367:HeLa Cells; D006801:Humans; D016547:Kinesins / Q000378:metabolism; D008954:Models, Biological; D008969:Molecular Sequence Data; D010766:Phosphorylation; D059748:Proteolysis; D040901:Proteomics; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013379:Substrate Specificity; D054875:Ubiquitination
chemical_list: C486566:KIFC1 protein, human; D011993:Recombinant Fusion Proteins; D064173:Anaphase-Promoting Complex-Cyclosome; C502735:KIF18A protein, human; D016547:Kinesins