Regulation of starch stores by a Ca2+-dependent protein kinase is essential for viable cyst development in Toxoplasma gondii
Details
Publication Year 2015-12-09,Volume 18,Issue #6,Page 670-681
Journal Title
Cell Host & Microbe
Publication Type
Journal Article
Abstract
Transmissible stages of Toxoplasma gondii store energy in the form of the carbohydrate amylopectin. Here, we show that the Ca2+-dependent protein kinase CDPK2 is a critical regulator of amylopectin metabolism. Increased synthesis and loss of degradation of amylopectin in CDPK2 deficient parasites results in the hyperaccumulation of this sugar polymer. A carbohydrate-binding module 20 (CBM20) targets CDPK2 to amylopectin stores, while the EF-hands regulate CDPK2 kinase activity in response to Ca2+ to modulate amylopectin levels. We identify enzymes involved in amylopectin turnover whose phosphorylation is dependent on CDPK2 activity. Strikingly, accumulation of massive amylopectin granules in CDPK2-deficient bradyzoite stages leads to gross morphological defects and complete ablation of cyst formation in a mouse model. Together these data show that Ca2+ signaling regulates carbohydrate metabolism in Toxoplasma and that the post-translational control of this pathway is required for normal cyst development.
Publisher
Elsevier
Research Division(s)
Infection And Immunity; Systems Biology And Personalised Medicine; Inflammation
Terms of Use/Rights Notice
Refer to copyright notice on published article.


Creation Date: 2015-12-10 11:27:48
Last Modified: 2015-12-15 02:11:01
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