The structure of the large regulatory α subunit of phosphorylase kinase examined by modeling and hydrogen-deuterium exchange.

ABSTRACT: Phosphorylase kinase (PhK), a 1.3 MDa regulatory enzyme complex in the glycogenolysis cascade, has four copies each of four subunits, (αβγδ)₄ , and 325 kDa of unique sequence (the mass of an αβγδ protomer). The α, β and δ subunits are regulatory, and contain allosteric activation sites that stimulate the activity of the catalytic γ subunit in response to diverse signaling molecules. Due to its size and complexity, no high resolution structures have been solved for the intact complex or its regulatory α and β subunits. Of PhK's four subunits, the least is known about the structure and function of its largest subunit, α. Here, we have modeled the full-length α subunit, compared that structure against previously predicted domains within this subunit, and performed hydrogen-deuteriu

SUBMITTER: Rimmer MA 

PROVIDER: S-EPMC5775172 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature