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Title: Spindle assembly in egg extracts of the Marsabit clawed frog, Xenopus borealis
Abstract

Egg extracts of the African clawed frogXenopus laevishave provided a cell‐free system instrumental in elucidating events of the cell cycle, including mechanisms of spindle assembly. Comparison with extracts from the diploid Western clawed frog,Xenopus tropicalis, which is smaller at the organism, cellular and subcellular levels, has enabled the identification of spindle size scaling factors. We set out to characterize the Marsabit clawed frog,Xenopus borealis, which is intermediate in size between the two species, but more recently diverged in evolution fromX. laevisthanX. tropicalis.X. borealiseggs were slightly smaller than those ofX. laevis, and slightly smaller spindles were assembled in egg extracts. Interestingly, microtubule distribution across the length of theX. borealisspindles differed from bothX. laevisandX. tropicalis. Extract mixing experiments revealed common scaling phenomena amongXenopusspecies, while characterization of spindle factors katanin, TPX2, and Ran indicate thatX. borealisspindles possess bothX. laevisandX. tropicalisfeatures. Thus,X. borealisegg extract provides a thirdin vitrosystem to investigate interspecies scaling and spindle morphometric variation.

 
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NSF-PAR ID:
10058920
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Cytoskeleton
Volume:
75
Issue:
6
ISSN:
1949-3584
Page Range / eLocation ID:
p. 244-257
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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