« Previous AbstractLetter: Odour-blindness to musk: simple recessive inheritance    Next AbstractDevelopment and testing of a whole-air sampler for measurement of personal exposure to volatile organic compounds »

Genetics

Title:		Generation of an isogenic collection of yeast actin mutants and identification of three interrelated phenotypes
Author(s):		Whitacre J; Davis D; Toenjes K; Brower S; Adams A;
Address:		"Department of Molecular & Cellular Biology, University of Arizona, Tucson, AZ 85721, USA. jodell@biomail.ucsd.edu"
Journal Title:		Genetics
Year:		2001
Volume:		157
Issue:		2
Page Number:		533 - 543
DOI:		10.1093/genetics/157.2.533
ISSN/ISBN:		0016-6731 (Print) 0016-6731 (Linking)
Abstract:		"A large collection of yeast actin mutations has been previously isolated and used in numerous studies of actin cytoskeletal function. However, the various mutations have been in congenic, rather than isogenic, backgrounds, making it difficult to compare the subtle phenotypes that are characteristic of these mutants. We have therefore placed 27 mutations in an isogenic background. We used a subset of these mutants to compare the degree to which different actin alleles are defective in sporulation, endocytosis, and growth on NaCl-containing media. We found that the three phenotypes are highly correlated. The correlations are specific and not merely a reflection of general growth defects, because the phenotypes are not correlated with growth rates under normal conditions. Significantly, those actin mutants exhibiting the most severe phenotypes in all three processes have altered residues that cluster to a small region of the actin crystal structure previously defined as the fimbrin (Sac6p)-binding site. We examined the relationship between endocytosis and growth on salt and found that shifting wild-type or actin mutant cells to high salt reduces the rate of alpha-factor internalization. These results suggest that actin mutants may be unable to grow on salt because of additive endocytic defects (due to mutation and salt)"
Keywords:		"Actins/chemistry/*genetics/metabolism Alleles Binding Sites Cell Division/genetics Cytoskeleton/metabolism Endocytosis/genetics Genotype Mating Factor Membrane Glycoproteins/metabolism *Microfilament Proteins Models, Molecular *Mutation Peptides/genetics;"
Notes:		"MedlineWhitacre, J Davis, D Toenjes, K Brower, S Adams, A eng GM45288/GM/NIGMS NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. 2001/02/07 Genetics. 2001 Feb; 157(2):533-43. doi: 10.1093/genetics/157.2.533"