Microcephalin and pericentrin regulate mitotic entry via centrosome-associated Chk1
نویسندگان
چکیده
Primary microcephaly, Seckel syndrome, and microcephalic osteodysplastic primordial dwarfism type II (MOPD II) are disorders exhibiting marked microcephaly, with small brain sizes reflecting reduced neuron production during fetal life. Although primary microcephaly can be caused by mutations in microcephalin (MCPH1), cells from patients with Seckel syndrome and MOPD II harbor mutations in ataxia telangiectasia and Rad3 related (ATR) or pericentrin (PCNT), leading to disturbed ATR signaling. In this study, we show that a lack of MCPH1 or PCNT results in a loss of Chk1 from centrosomes with subsequently deregulated activation of centrosomal cyclin B-Cdk1.
منابع مشابه
Neurogenesis: Premature Mitotic Entry Lets Cleavage Planes Take Off!
Mutations in the gene microcephalin/MCPH1 result in the neurodevelopmental disease microcephaly. A recent report provides evidence that MCPH1 controls neuroprogenitor entry into mitosis via the Chk1-Cdc25b centrosome maturation pathway.
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