Biomaterial Database

Polarization of yeast cells in spatial gradients of alpha mating factor. 1993

J E Segall

Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY 10461.

The process of cell fusion during mating of the yeast Saccharomyces cerevisiae is mediated by factors secreted by the mating partners. Spatial gradients of one of these mating factors, alpha-factor, polarized the growth of projections by MATa cells. The site of previous budding did not affect the direction of polarization, and subsequent budding was also polarized if mating factor was removed. Orientation occurred in the presence of nocodazole, suggesting that microtubules were not critical. At extremely low concentrations of alpha-factor, sst2-mutants (which in genetic studies do not discriminate between partners producing different amounts of alpha-factor) were able to polarize their projections. The sensitivity of this spatial sensing mechanism in wild-type cells is such that differences in receptor occupancy estimated to be about 1% are sufficient for orientation.

UI	MeSH Term	Description	Entries
D010455	Peptides	Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are considered to be larger versions of peptides that can form into complex structures such as ENZYMES and RECEPTORS.	Peptide,Polypeptide,Polypeptides
D011956	Receptors, Cell Surface	Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.	Cell Surface Receptor,Cell Surface Receptors,Hormone Receptors, Cell Surface,Receptors, Endogenous Substances,Cell Surface Hormone Receptors,Endogenous Substances Receptors,Receptor, Cell Surface,Surface Receptor, Cell
D002633	Chemotaxis	The movement of cells or organisms toward or away from a substance in response to its concentration gradient.	Haptotaxis
D005838	Genotype	The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.	Genogroup,Genogroups,Genotypes
D000072235	Mating Factor	A protein also known as pheromone mating factor that occurs on the surfaces of organisms such as yeast and fungi.	Mating Hormone,Pheromone a-Factor,Pheromone alpha-Factor,Sexual Agglutination Factor,alpha-Agglutinin (Fungal),alpha-Factor (Fungal),alpha-Mating Factor,Agglutination Factor, Sexual,Factor, Mating,Factor, Sexual Agglutination,Factor, alpha-Mating,Hormone, Mating,Pheromone a Factor,Pheromone alpha Factor,a-Factor, Pheromone,alpha Mating Factor,alpha-Factor, Pheromone
D012441	Saccharomyces cerevisiae	A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.	Baker's Yeast,Brewer's Yeast,Candida robusta,S. cerevisiae,Saccharomyces capensis,Saccharomyces italicus,Saccharomyces oviformis,Saccharomyces uvarum var. melibiosus,Yeast, Baker's,Yeast, Brewer's,Baker Yeast,S cerevisiae,Baker's Yeasts,Yeast, Baker
D014157	Transcription Factors	Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.	Transcription Factor,Factor, Transcription,Factors, Transcription
D051964	Receptors, Mating Factor	A family of pheromone receptors that were initially discovered in SACCHAROMYCES CEREVISIAE as proteins necessary for fungal conjugation. Each mating factor receptor is expressed in HAPLOID CELLS of a single mating type.	Mating Factor Receptors,A-Factor Receptor,Mating Factor Receptor A,Mating Factor Receptor Ste2,Mating Factor Receptor Ste3,Mating Factor Receptor alpha,alpha-Factor Receptor,A Factor Receptor,Receptor, A-Factor,Receptor, alpha-Factor,alpha Factor Receptor
D018000	Receptors, Peptide	Cell surface receptors that bind peptide messengers with high affinity and regulate intracellular signals which influence the behavior of cells.	Peptide Hormone Receptors,Peptide Receptors,Peptide Hormone Receptor,Peptide Receptor,Receptors, Peptide Hormones,Receptors, Peptides,Hormone Receptor, Peptide,Hormone Receptors, Peptide,Hormones Receptors, Peptide,Peptide Hormones Receptors,Peptides Receptors,Receptor, Peptide,Receptor, Peptide Hormone,Receptors, Peptide Hormone