Structural Characterization of the Catalytic Gamma and Regulatory Beta Subunits of Phosphorylase Kinase in the Context of the Hexadecameric Enzyme Complex
Abstract
In the tightly regulated glycogenolysis cascade, the breakdown of glycogen to glucose-1-phosphate, phosphorylase kinase (PhK) plays a key role in regulating the activity of glycogen phosphorylase. PhK is a 1.3 MDa hexadecamer, with four copies each of four different subunits (alpha, beta, gamma and delta), making the study of its structure challenging. Using hydrogen-deuterium exchange, we have analyzed the regulatory beta subunit and the catalytic gamma subunit in the context of the intact non-activated PhK complex to study the structure of these subunits and identify regions of surface exposure. Our data suggest that within the non-activated complex the gamma subunit assumes an activated conformation and are consistent with a previous docking model of the beta subunit within the cryoelectron microscopy envelope of PhK.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 03, 2017
- Accession Number
- AD1103127
Entities
People
- Antonio Artigues
- Gerald M. Carlson
- Mary A. Rimmer
- Owen W. Nadeau
Organizations
- United States Naval Research Laboratory