Saccharomyces cerevisiae contains two functional genes encoding 3-hydroxy-3-methylglutaryl-coenzyme A reductase.

نویسندگان

  • M E Basson
  • M Thorsness
  • J Rine
چکیده

We have isolated two genes from yeast encoding 3-hydroxy-3-methylglutaryl-coenzyme A reductase [hydroxymethylglutaryl-coenzyme A reductase (NADPH); HMG-CoA reductase; EC 1.1.1.34], the rate-limiting enzyme of sterol biosynthesis. These genes, HMG1 and HMG2, were identified by hybridization to a cDNA clone encoding hamster HMG-CoA reductase. DNA sequence analysis reveals homology between the amino acid sequence of the proteins encoded by the two yeast genes and the carboxyl-terminal half of the hamster protein. Cells containing mutant alleles of both HMG1 and HMG2 are unable to undergo spore germination and vegetative growth. However, cells containing a mutant allele of either HMG1 or HMG2 are viable but are more sensitive to compactin, a competitive inhibitor of HMG-CoA reductase, than are wild-type cells. Assays of HMG-CoA reductase activity in extracts from hmg1- and hmg2- mutants indicate that HMG1 contributes at least 83% of the activity found in wild-type cells.

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عنوان ژورنال:
  • Proceedings of the National Academy of Sciences of the United States of America

دوره 83 15  شماره 

صفحات  -

تاریخ انتشار 1986