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Mol Cell Biol. 1987 July; 7(7): 2316–2328.
PMCID: PMC365362

Two genes required for cell fusion during yeast conjugation: evidence for a pheromone-induced surface protein.

Abstract

We characterized two genes, FUS1 and FUS2, which are required for fusion of Saccharomyces cerevisiae cells during conjugation. Mutations in these genes lead to an interruption of the mating process at a point just before cytoplasmic fusion; the partition dividing the mating pair remains undissolved several hours after the cells have initially formed a stable "prezygote." Fusion is only moderately impaired when the two parents together harbor one or two mutant fus genes, and it is severely compromised only when three or all four fus genes are inactivated. Cloning of FUS1 and FUS2 revealed that they share some functional homology; FUS1 on a high-copy number plasmid can partially suppress a fus2 mutant, and vice versa. FUS1 remains essentially unexpressed in vegetative cells, but is strongly induced by incubation of haploid cells with the appropriate mating pheromone. Immunofluorescence microscopy of alpha factor-induced a cells harboring a fus1-LACZ fusion showed the fusion protein to be localized at the cell surface, concentrated at one end of the cell (the shmoo tip). FUS1 maps near HIS4, and the intervening region (including BIK1, a gene required for nuclear fusion) was sequenced along with FUS1. The sequence of FUS1 revealed the presence of three copies of a hexamer (TGAAAC) conserved in the 5' noncoding regions of other pheromone-inducible genes. The deduced FUS1 protein sequence exhibits a striking concentration of serines and threonines at the amino terminus (46%; 33 of 71), followed by a 25-amino acid hydrophobic stretch and a predominantly hydrophilic carboxy terminus, which contains several potential N-glycosylation sites (Asn-X-Ser/Thr). This sequence suggests that FUS1 encodes a membrane-anchored glycoprotein with both N- and O-linked sugars.

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  • Biggin MD, Gibson TJ, Hong GF. Buffer gradient gels and 35S label as an aid to rapid DNA sequence determination. Proc Natl Acad Sci U S A. 1983 Jul;80(13):3963–3965. [PubMed]
  • Bresch C, Müller G, Egel R. Genes involved in meiosis and sporulation of a yeast. Mol Gen Genet. 1968;102(4):301–306. [PubMed]
  • Bulawa CE, Slater M, Cabib E, Au-Young J, Sburlati A, Adair WL, Jr, Robbins PW. The S. cerevisiae structural gene for chitin synthase is not required for chitin synthesis in vivo. Cell. 1986 Jul 18;46(2):213–225. [PubMed]
  • Byers B, Goetsch L. Behavior of spindles and spindle plaques in the cell cycle and conjugation of Saccharomyces cerevisiae. J Bacteriol. 1975 Oct;124(1):511–523. [PMC free article] [PubMed]
  • Carlson M, Botstein D. Two differentially regulated mRNAs with different 5' ends encode secreted with intracellular forms of yeast invertase. Cell. 1982 Jan;28(1):145–154. [PubMed]
  • Conde J, Fink GR. A mutant of Saccharomyces cerevisiae defective for nuclear fusion. Proc Natl Acad Sci U S A. 1976 Oct;73(10):3651–3655. [PubMed]
  • Curran BP, Carter BL. Alpha-factor enhancement of hybrid formation by protoplast fusion in Saccharomyces cerevisiae II. Curr Genet. 1986;10(12):943–945. [PubMed]
  • Davis CG, Elhammer A, Russell DW, Schneider WJ, Kornfeld S, Brown MS, Goldstein JL. Deletion of clustered O-linked carbohydrates does not impair function of low density lipoprotein receptor in transfected fibroblasts. J Biol Chem. 1986 Feb 25;261(6):2828–2838. [PubMed]
  • DeFeo-Jones D, Scolnick EM, Koller R, Dhar R. ras-Related gene sequences identified and isolated from Saccharomyces cerevisiae. Nature. 1983 Dec 15;306(5944):707–709. [PubMed]
  • Donahue TF, Daves RS, Lucchini G, Fink GR. A short nucleotide sequence required for regulation of HIS4 by the general control system of yeast. Cell. 1983 Jan;32(1):89–98. [PubMed]
  • Donahue TF, Farabaugh PJ, Fink GR. The nucleotide sequence of the HIS4 region of yeast. Gene. 1982 Apr;18(1):47–59. [PubMed]
  • Duntze W, MacKay V, Manney TR. Saccharomyces cerevisiae: a diffusible sex factor. Science. 1970 Jun 19;168(3938):1472–1473. [PubMed]
  • Duntze W, Stötzler D, Bücking-Throm E, Kalbitzer S. Purification and partial characterization of -factor, a mating-type specific inhibitor of cell reproduction from Saccharomyces cerevisiae. Eur J Biochem. 1973 Jun;35(2):357–365. [PubMed]
  • Farabaugh PJ, Fink GR. Insertion of the eukaryotic transposable element Ty1 creates a 5-base pair duplication. Nature. 1980 Jul 24;286(5771):352–356. [PubMed]
  • Fink GR, Styles CA. Curing of a killer factor in Saccharomyces cerevisiae. Proc Natl Acad Sci U S A. 1972 Oct;69(10):2846–2849. [PubMed]
  • Goldring ES, Grossman LI, Krupnick D, Cryer DR, Marmur J. The petite mutation in yeast. Loss of mitochondrial deoxyribonucleic acid during induction of petites with ethidium bromide. J Mol Biol. 1970 Sep 14;52(2):323–335. [PubMed]
  • Guarente L, Lalonde B, Gifford P, Alani E. Distinctly regulated tandem upstream activation sites mediate catabolite repression of the CYC1 gene of S. cerevisiae. Cell. 1984 Feb;36(2):503–511. [PubMed]
  • Hereford L, Fahrner K, Woolford J, Jr, Rosbash M, Kaback DB. Isolation of yeast histone genes H2A and H2B. Cell. 1979 Dec;18(4):1261–1271. [PubMed]
  • Holland JP, Holland MJ. Structural comparison of two nontandemly repeated yeast glyceraldehyde-3-phosphate dehydrogenase genes. J Biol Chem. 1980 Mar 25;255(6):2596–2605. [PubMed]
  • Holland MJ, Holland JP, Thill GP, Jackson KA. The primary structures of two yeast enolase genes. Homology between the 5' noncoding flanking regions of yeast enolase and glyceraldehyde-3-phosphate dehydrogenase genes. J Biol Chem. 1981 Feb 10;256(3):1385–1395. [PubMed]
  • Julius D, Brake A, Blair L, Kunisawa R, Thorner J. Isolation of the putative structural gene for the lysine-arginine-cleaving endopeptidase required for processing of yeast prepro-alpha-factor. Cell. 1984 Jul;37(3):1075–1089. [PubMed]
  • Kilmartin JV, Adams AE. Structural rearrangements of tubulin and actin during the cell cycle of the yeast Saccharomyces. J Cell Biol. 1984 Mar;98(3):922–933. [PMC free article] [PubMed]
  • Laz TM, Pietras DF, Sherman F. Differential regulation of the duplicated isocytochrome c genes in yeast. Proc Natl Acad Sci U S A. 1984 Jul;81(14):4475–4479. [PubMed]
  • Bertoglio J, Laldjim B, Doré JF. Mouse erythrocyte rosette formation by human lymphoid cell lines. Scand J Immunol. 1979;10(2):153–159. [PubMed]
  • Orr-Weaver TL, Szostak JW, Rothstein RJ. Yeast transformation: a model system for the study of recombination. Proc Natl Acad Sci U S A. 1981 Oct;78(10):6354–6358. [PubMed]
  • Osumi M, Shimoda C, Yanagishima N. Mating reaction in Saccharomyces cerevisiae. V. Changes in the fine structure during the mating reaction. Arch Mikrobiol. 1974 Apr 10;97(1):27–38. [PubMed]
  • Rogers D, Bussey H. Fidelity of conjugation in Saccharomyces cerevisiae. Mol Gen Genet. 1978 Jun 14;162(2):173–182. [PubMed]
  • Roeder GS, Fink GR. DNA rearrangements associated with a transposable element in yeast. Cell. 1980 Aug;21(1):239–249. [PubMed]
  • Rose MD, Price BR, Fink GR. Saccharomyces cerevisiae nuclear fusion requires prior activation by alpha factor. Mol Cell Biol. 1986 Oct;6(10):3490–3497. [PMC free article] [PubMed]
  • Rothstein RJ. One-step gene disruption in yeast. Methods Enzymol. 1983;101:202–211. [PubMed]
  • Sakai K, Yanagishima N. Mating reaction in Saccharomyces cerevisiae. II. Hormonal regulation of agglutinability of a type cells. Arch Mikrobiol. 1972;84(3):191–198. [PubMed]
  • Sanger F, Nicklen S, Coulson AR. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. [PubMed]
  • Santos T, del Rey F, Conde J, Villanueva JR, Nombela C. Saccharomyces cerevisiae mutant defective in exo-1,3-beta-glucanase production. J Bacteriol. 1979 Aug;139(2):333–338. [PMC free article] [PubMed]
  • Schatz PJ, Pillus L, Grisafi P, Solomon F, Botstein D. Two functional alpha-tubulin genes of the yeast Saccharomyces cerevisiae encode divergent proteins. Mol Cell Biol. 1986 Nov;6(11):3711–3721. [PMC free article] [PubMed]
  • Shortle D. A genetic system for analysis of staphylococcal nuclease. Gene. 1983 May-Jun;22(2-3):181–189. [PubMed]
  • Singh A, Chen EY, Lugovoy JM, Chang CN, Hitzeman RA, Seeburg PH. Saccharomyces cerevisiae contains two discrete genes coding for the alpha-factor pheromone. Nucleic Acids Res. 1983 Jun 25;11(12):4049–4063. [PMC free article] [PubMed]
  • Tatchell K, Chaleff DT, DeFeo-Jones D, Scolnick EM. Requirement of either of a pair of ras-related genes of Saccharomyces cerevisiae for spore viability. Nature. 1984 Jun 7;309(5968):523–527. [PubMed]
  • Terrance K, Lipke PN. Sexual agglutination in Saccharomyces cerevisiae. J Bacteriol. 1981 Dec;148(3):889–896. [PMC free article] [PubMed]
  • Tkacz JS, MacKay VL. Sexual conjugation in yeast. Cell surface changes in response to the action of mating hormones. J Cell Biol. 1979 Feb;80(2):326–333. [PMC free article] [PubMed]
  • Wilkinson LE, Pringle JR. Transient G1 arrest of S. cerevisiae cells of mating type alpha by a factor produced by cells of mating type a. Exp Cell Res. 1974 Nov;89(1):175–187. [PubMed]

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