Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.
Cell. December 9, 2011; 147 (6): 1397-407.

Katanin contributes to interspecies spindle length scaling in Xenopus.

Loughlin R , Wilbur JD , McNally FJ , Nédélec FJ , Heald R .

Bipolar spindles must separate chromosomes by the appropriate distance during cell division, but mechanisms determining spindle length are poorly understood. Based on a 2D model of meiotic spindle assembly, we predicted that higher localized microtubule (MT) depolymerization rates could generate the shorter spindles observed in egg extracts of X. tropicalis compared to X. laevis. We found that katanin-dependent MT severing was increased in X. tropicalis, which, unlike X. laevis, lacks an inhibitory phosphorylation site in the katanin p60 catalytic subunit. Katanin inhibition lengthened spindles in both species. In X. tropicalis, k-fiber MT bundles that connect to chromosomes at their kinetochores extended through spindle poles, disrupting them. In both X. tropicalis extracts and the spindle simulation, a balance between k-fiber number and MT depolymerization is required to maintain spindle morphology. Thus, mechanisms have evolved in different species to scale spindle size and coordinate regulation of multiple MT populations in order to generate a robust steady-state structure.

PubMed ID: 22153081
PMC ID: PMC3240848
Article link: Cell.
Grant support: DP1 OD000818 NIH HHS , DP1 OD000818-05 NIH HHS , R01 GM079421 NIGMS NIH HHS

Genes referenced: arhgef5

External Resources:

Bird, 2008, Pubmed[+]

Xenbase: The Xenopus laevis and X. tropicalis resource.
Version: 4.9.0
Major funding for Xenbase is provided by the National Institute of Child Health and Human Development, grant P41 HD064556