Identification of the substrate recruitment mechanism of the muscle glycogen protein phosphatase 1 holoenzyme.

ABSTRACT: Glycogen is the primary storage form of glucose. Glycogen synthesis and breakdown are tightly controlled by glycogen synthase (GYS) and phosphorylase, respectively. The enzyme responsible for dephosphorylating GYS and phosphorylase, which results in their activation (GYS) or inactivation (phosphorylase) to robustly stimulate glycogen synthesis, is protein phosphatase 1 (PP1). However, our understanding of how PP1 recruits these substrates is limited. Here, we show how PP1, together with its muscle glycogen-targeting (G_M) regulatory subunit, recruits and selectively dephosphorylates its substrates. Our molecular data reveal that the G_M carbohydrate binding module (G_M ^CBM21), which is amino-terminal to the G_M PP1 binding domain, has a du

SUBMITTER: Kumar GS 

PROVIDER: S-EPMC6235537 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature