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.
XB-ART-20583
Cell 1994 Nov 04;793:475-86.
Show Gene links Show Anatomy links

A MAP kinase-dependent spindle assembly checkpoint in Xenopus egg extracts.

Minshull J , Sun H , Tonks NK , Murray AW .


???displayArticle.abstract???
Like early Xenopus embryos, extracts made from Xenopus eggs lack the cell cycle checkpoint that keeps anaphase from occurring before spindle assembly is complete. At very high densities of sperm nuclei, however, microtubule depolymerization arrests the extracts in mitosis. The arrested extracts have high levels of maturation-promoting factor activity, fail to degrade cyclin B, and contain activated ERK2/mitogen-activated protein (MAP) kinase. The addition of the purified MAP kinase-specific phosphatase MKP-1 demonstrates that MAP kinase activity is required for both the establishment and maintenance of the mitotic arrest induced by spindle depolymerization. Increased calcium concentrations, which release unfertilized frog eggs from their natural arrest in metaphase of meiosis II, have no effect on the mitotic arrest.

???displayArticle.pubmedLink??? 7954813
???displayArticle.link??? Cell
???displayArticle.grants??? [+]

Species referenced: Xenopus
Genes referenced: ccnb1.2 cdk1 mapk1