%0 Journal Article
%T Activation of an AMP-activated protein kinase is involved in post-diapause development of Artemia franciscana encysted embryos
%A Xiao-Jing Zhu
%A Jie-Qiong Dai
%A Xin Tan
%A Yang Zhao
%A Wei-Jun Yang
%J BMC Developmental Biology
%D 2009
%I BioMed Central
%R 10.1186/1471-213x-9-21
%X Herein we report the specific activation of an AMP-activated protein kinase (AMPK) in the post-diapause developmental process of Artemia. Using a phospho-AMPK¦Į antibody, AMPK was shown to be phosphorylated in the post-diapause developmental process. Results of kinase assay analysis showed that this phosphorylation is essential for AMPK activation. Using whole-mount immunohistochemistry, phosphorylated AMPK was shown to be predominantly located in the ectoderm of the early developed embryos in a ring shape; however, the location and shape of the activation region changed as development proceeded. Additionally, Western blotting analysis on different portions of the cyst extracts showed that phosphorylated AMPK¦Į localized to the nuclei and this location was not affected by intracellular pH. Confocal microscopy analysis of immunofluorescent stained cyst nuclei further showed that AMPK¦Į localized to the nuclei when activated. Moreover, cellular AMP, ADP, and ATP levels in developing cysts were determined by HPLC, and the results showed that the activation of Artemia AMPK may not be associated with cellular AMP:ATP ratios, suggesting other pathways for regulation of Artemia AMPK activity.Together, we report evidence demonstrating the activation of AMPK in Artemia developing cysts and present an argument for its role in the development-related gene expression and energy control in certain cells during post-diapause development of Artemia.Artemia is a species of primitive crustaceans capable of producing diapause encysted embryos (cysts) to survive adverse conditions. The cyst, composed of about 4000 cells and developmentally arrested at the gastrula stage, is remarkably resistant to physiologic stressors [1]. Diapause embryos remain in dormancy and will not resume development until they are activated by transient exposure to a specific environmental stimulus. Activated cysts require only suitable environmental conditions to resume metabolism and development, and eventually
%U http://www.biomedcentral.com/1471-213X/9/21