title: The Aspergillus nidulans bimC4 mutation provides an excellent tool for identification of kinesin-14 inhibitors.
abstract: Centrosome amplification is a hallmark of many types of cancer cells, and clustering of multiple centrosomes is critical for cancer cell survival and proliferation. Human kinesin-14 HSET/KFIC1 is essential for centrosome clustering, and its inhibition leads to the specific killing of cancer cells with extra centrosomes. Since kinesin-14 motor domains are conserved evolutionarily, we conceived a strategy of obtaining kinesin-14 inhibitors using Aspergillus nidulans, based on the previous result that loss of the kinesin-14 KlpA rescues the non-viability of the bimC4 kinesin-5 mutant at 42 °C. However, it was unclear whether alteration of BimC or any other non-KlpA protein would be a major factor reversing the lethality of the bimC4 mutant. Here we performed a genome-wide screen for bimC4 suppressors and obtained fifteen suppressor strains. None of the suppressor mutations maps to bimC. The vast majority of them contain mutations in the klpA gene, most of which are missense mutations affecting the C-terminal motor domain. Our study confirms that the bimC4 mutant is suitable for a cell-based screen for chemical inhibitors of kinesin-14. Since the selection is based on enhanced growth rather than diminished growth, cytotoxic compounds can be excluded.
authors.affiliation: Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences - F. Edward Hébert School of Medicine, Bethesda, MD, United States; Richard Montgomery High School, Rockville, MD, United States.
authors.forename: Betsy
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences - F. Edward Hébert School of Medicine, Bethesda, MD, United States; River Hill High School, Clarksville, MD, United States; USU Summer Research Training Program (USRTP), United States.
authors.forename: Kristin
authors.initials: K
authors.lastname: Li
authors.affiliation: Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences - F. Edward Hébert School of Medicine, Bethesda, MD, United States; Wootton High School, Rockville, MD, United States.
authors.forename: Max
authors.initials: M
authors.lastname: Jin
authors.affiliation: Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences - F. Edward Hébert School of Medicine, Bethesda, MD, United States.
authors.forename: Rongde
authors.initials: R
authors.lastname: Qiu
authors.affiliation: Department of Plant Biology, UC Davis, Davis, CA, United States.
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
authors.affiliation: Department of Molecular Biosciences, College of Liberal Arts and Sciences, The University of Kansas, Lawrence, KS, United States.
authors.forename: Berl R
authors.initials: BR
authors.lastname: Oakley
authors.affiliation: Department of Biochemistry and Molecular Biology, The Uniformed Services University of the Health Sciences - F. Edward Hébert School of Medicine, Bethesda, MD, United States. Electronic address: xin.xiang@usuhs.edu.
authors.forename: Xin
authors.initials: X
authors.lastname: Xiang
mesh_terms: D000595:Amino Acid Sequence; D001233:Aspergillus nidulans / Q000235:genetics*; D055808:Drug Discovery; D005656:Fungal Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000235:genetics*; D016547:Kinesins / Q000037:antagonists & inhibitors* / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D016415:Sequence Alignment; D013696:Temperature
chemical_list: D005656:Fungal Proteins; C444432:KLPA protein, Aspergillus nidulans; D016547:Kinesins
keywords: Aspergillus nidulans; Cancer-drug screening; Kinesin-14; Kinesin-5; Suppressor mutations