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-39592
Science 2009 Apr 24;3245926:509-12. doi: 10.1126/science.1169498.
Show Gene links Show Anatomy links

Tuning the activation threshold of a kinase network by nested feedback loops.

Justman QA , Serber Z , Ferrell JE , El-Samad H , Shokat KM .


???displayArticle.abstract???
Determining proper responsiveness to incoming signals is fundamental to all biological systems. We demonstrate that intracellular signaling nodes can tune a signaling network's response threshold away from the basal median effective concentration established by ligand-receptor interactions. Focusing on the bistable kinase network that governs progesterone-induced meiotic entry in Xenopus oocytes, we characterized glycogen synthase kinase-3beta (GSK-3beta) as a dampener of progesterone responsiveness. GSK-3beta engages the meiotic kinase network through a double-negative feedback loop; this specific feedback architecture raises the progesterone threshold in correspondence with the strength of double-negative signaling. We also identified a marker of nutritional status, l-leucine, which lowers the progesterone threshold, indicating that oocytes integrate additional signals into their cell-fate decisions by modulating progesterone responsiveness.

???displayArticle.pubmedLink??? 19390045
???displayArticle.pmcLink??? PMC2880456
???displayArticle.link??? Science
???displayArticle.grants??? [+]


References [+] :
Acar, Enhancement of cellular memory by reducing stochastic transitions. 2005, Pubmed