Deficiency of a glycogen synthase-associated protein, Epm2aip1, causes decreased glycogen synthesis and hepatic insulin resistance.
نویسندگان
چکیده
Glycogen synthesis is a major component of the insulin response, and defective glycogen synthesis is a major portion of insulin resistance. Insulin regulates glycogen synthase (GS) through incompletely defined pathways that activate the enzyme through dephosphorylation and, more potently, allosteric activation. We identify Epm2aip1 as a GS-associated protein. We show that the absence of Epm2aip1 in mice impairs allosteric activation of GS by glucose 6-phosphate, decreases hepatic glycogen synthesis, increases liver fat, causes hepatic insulin resistance, and protects against age-related obesity. Our work identifies a novel GS-associated GS activity-modulating component of insulin resistance.
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عنوان ژورنال:
- The Journal of biological chemistry
دوره 288 48 شماره
صفحات -
تاریخ انتشار 2013