Studies of the residual glycogen branching enzyme activity present in human skin fibroblasts from patients with type IV glycogen storage disease.

Abstract

Human skin fibroblasts from patients with Type IV glycogen storage disease, in which there is a demonstrable deficiency of glycogen branching enzyme, were shown to be able to synthesize [14C]glycogen containing [14C]glucose at branch points when sonicates containing endogenous glycogen synthase a were incubated with UDP[14C]glucose. The branch point content of the glycogen synthesized by the Type IV cells was essentially the same as that formed by normal cells, but the total synthetic capacity of the Type IV cells was lower. A new assay for the branching enzyme using glycogen synthase as the indicator enzyme has been developed. Using this assay it has been shown that the residual branching enzyme of affected children and of their heterozygote parents is less easily inhibited by an IgG antibody raised in rabbits against the normal human liver enzyme than is the branching enzyme of normal fibroblasts.

• Authors: D H Brown, B I Brown
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 111 Issue 2 Pg. 636-43 (Mar 16 1983) ISSN: 0006-291X [Print] United States
• PMID: 6220706 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Glucosyltransferases
• Glycogen Synthase
• 1,4-alpha-Glucan Branching Enzyme
• Uridine Diphosphate Glucose

Topics

• 1,4-alpha-Glucan Branching Enzyme (analysis)
• Cells, Cultured
• Cross Reactions
• Fibroblasts (enzymology)
• Glucosyltransferases (analysis)
• Glycogen Storage Disease (enzymology)
• Glycogen Storage Disease Type IV (enzymology)
• Glycogen Synthase (analysis)
• Humans
• Liver (enzymology)
• Skin (enzymology)
• Uridine Diphosphate Glucose (metabolism)