Diverse essential functions revealed by complementing yeast calmodulin mutants.

Y Ohya; D Botstein

doi:10.1126/science.8310294

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PubMed · 8310294

Diverse essential functions revealed by complementing yeast calmodulin mutants.

Y Ohya·D Botstein

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Abstract

Calmodulin, a cytoplasmic calcium-binding protein, is indispensable for eukaryotic cell growth. Examination of 14 temperature-sensitive yeast mutants bearing one or more phenylalanine to alanine substitutions in the single essential calmodulin gene of yeast (CMD1) revealed diverse essential functions. Mutations could be classified into four intragenic complementation groups. Each group showed different characteristic functional defects in actin organization, calmodulin localization, nuclear division, or bud emergence. Phenylalanine residues implicated in calmodulin localization and nuclear division are located in the amino-terminal half of the protein, whereas those implicated in actin organization and bud emergence are located in the carboxyl-terminal half.

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Actins Calmodulin Cell Cycle DNA Replication Genes, Fungal Genetic Complementation Test Mutagenesis, Site-Directed Mutation Phenotype Saccharomyces cerevisiae Temperature Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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Y Ohya, D Botstein. 1994-02-18. Diverse essential functions revealed by complementing yeast calmodulin mutants.. https://doi.org/10.1126/science.8310294

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