Coordinate regulation of glycogen metabolism in the yeast Saccharomyces cerevisiae. Induction of glycogen branching enzyme.

The yeast glycogen branching enzyme (EC 2.4.1.18) is shown to be induced in batch culture simultaneously with the onset of intracellular glycogen accumulation. The branching enzyme structural gene (GLC3) has been cloned. Its predicted amino acid sequence is very similar to procaryotic branching enzymes. Northern analysis indicates that GLC3 mRNA abundance increases in late exponential growth phase coincident with glycogen accumulation. Disruption of the branching enzyme structural gene establishes that branching enzyme activity is an absolute requirement for maximal glycogen synthesis.