Regulation of fungal gene expression

Abstract

Disclosed herein are methods for regulating fungal gene expression, and reagents for carrying out those methods.

What is claimed is:  
     
         1 . A method for determining whether a candidate compound decreases the expression of a gene operably linked to a fungal invasin gene promoter, said method comprising 
 (a) providing a fungus expressing said gene operably linked to a fungal invasin gene promoter;    (b) contacting said fungus with said candidate compound; and    (c) detecting or measuring expression of said gene following contact of the fungus with said candidate compound.    
     
     
         2 . The method of  claim 1 , wherein said fungus is a wild-type strain.  
     
     
         3 . The method of  claim 2 , wherein said wild-type strain is  Saccharomyces cerevisiae, Candida albicans,  or  Aspergillus nidulans.    
     
     
         4 . The method of  claim 1 , wherein said fungus is a mutant strain.  
     
     
         5 . The method of  claim 1 , wherein said fungus is a transgenic fungus  
     
     
         6 . The method of  claim 1 , wherein said gene comprises a fungal invasin gene.  
     
     
         7 . The method of  claim 6 , wherein said fungal invasin gene is FLO11 or MUC1.  
     
     
         8 . The method of  claim 1 , wherein said fungal invasin gene is AFL1, DHH1, INV1, INV5, INV6, INV7, INV8, INV9, INV10, INV11, INV12, INV13, INV14, INV15, BEM2, CDC25, HOG1, IRA1, MCM1, MGA1, PET9, PHD2, PHO23, PTC1, RIM15, SFL1, SRB11, SSD1, STE21, STP22, SWI4, TPK2, TPK3, RIM1, or YPR1  
     
     
         9 . The method of  claim 1 , wherein said gene comprises a reporter gene.  
     
     
         10 . The method of  claim 9 , wherein said reporter gene is lacZ, URA3, or HIS3.  
     
     
         11 . The method of  claim 1 , wherein said fungal invasin gene promoter is the FLO11, MUC1, STA1, STA2, or STA3 gene promoter.  
     
     
         12 . The method of  claim 1 , wherein said fungal invasin gene promoter is the AFL1, DHH1, INV1, INV5, INV6, INV7, INV8, INV9, INV10, INV11, INV12, INV13, RIM1, INV14, INV15, BEM2, CDC25, HOG1, IRA1, MCM1, MGA1, PET9, PHD2, PHO23, PTC1, RIM15, SFL1, SRB11, SSD1, STE21, STP22, SWI4, TPK2, TPK3, or YPR1 gene promoter.  
     
     
         13 . The method of  claim 1 , wherein said fungal invasin gene promoter is a fragment or deletion of a fungal invasin gene promoter.  
     
     
         14 . The method of  claim 13 , wherein said fragment is fused to a basal promoter.  
     
     
         15 . The method of  claim 14 , wherein said basal promoter comprises PGK1, ADH1, GAL1-10, tet-R, MET25, CYC1 or CUP1.  
     
     
         16 . The method of  claim 1 , wherein said gene expression is measured by assaying the protein level of the expressed gene.  
     
     
         17 . The method of  claim 1 , wherein said gene expression is measured by assaying the RNA level of the expressed gene.  
     
     
         18 . The method of  claim 6 , wherein a decrease in the expression of said fungal invasin gene inhibits fungal invasion.  
     
     
         19 . The method of  claim 6 , wherein a decrease in the expression of said fungal invasin gene inhibits the switch from yeast form to pseudohyphal growth.  
     
     
         20 . The method of  claim 1 , wherein said candidate compound inhibits or decreases the pathogenicity of a fungus.  
     
     
         21 . A method for determining whether a candidate compound increases the expression of a gene operably linked to a fungal invasin gene promoter, said method comprising 
 (a) providing a fungus expressing said gene operably linked to a fungal invasin gene promoter;    (b) contacting said fungus with said candidate compound; and    (c) detecting or measuring expression of said gene following contact of the fungus with said candidate compound.    
     
     
         22 . The method of  claim 21 , wherein said fungus is a wild-type strain.  
     
     
         23 . The method of  claim 22  wherein said wild-type strain is  Saccharomyces cerevisiae, Aspergillus nidulans, Penicillium chrysogenum,  or  Acremonium chrysogenum.    
     
     
         24 . The method of  claim 21 , wherein said fungus is a mutant strain.  
     
     
         25 . The method of  claim 21 , wherein said fungus is a transgenic fungus  
     
     
         26 . The method of  claim 21 , wherein said gene comprises a fungal invasin gene.  
     
     
         27 . The method of  claim 26 , wherein said fungal invasin gene is FLO11 or MUC1.  
     
     
         28 . The method of  claim 26 , wherein said fungal invasin gene is AFL1, DHH1, INV1, INV5, INV6, INV7, INV8, INV9, INV10, INV11, RIM1, INV12, INV13, INV14, INV15, BEM2, CDC25, HOG1, IRA1, MCM1, MGA1, PET9, PHD2, PHO23, PTC1, RIM15, SFL1, SRB11, SSD1, STE21, STP22, SWI4, TPK2, TPK3, or YPR1  
     
     
         29 . The method of  claim 21 , wherein said gene comprises a reporter gene.  
     
     
         30 . The method of  claim 29 , wherein said reporter gene is lacZ, URA3, or HIS3.  
     
     
         31 . The method of  claim 21 , wherein said fungal invasin gene promoter is the FLO11, MUC1, STA1, STA2, or STA3 gene promoter.  
     
     
         32 . The method of  claim 21 , wherein said fungal invasin gene promoter is the AFL1, DHH1, INV1, INV5, INV6, INV7, INV8, INV9, INV10, INV11, INV12, INV13, INV14, INV15, BEM2, CDC25, HOG1, IRA1, MCM1, MGA1, PET9, PHD2, PHO23, PTC1, RIM15, SFL1, SRB11, SSD1, STE21, STP22, SWI4, TPK2, RIM1, TPK3, or YPR1 gene promoter.  
     
     
         33 . The method of  claim 21 , wherein said fungal invasin gene promoter is a fragment or deletion of a fungal invasin gene promoter.  
     
     
         34 . The method of  claim 33 , wherein said fragment is fused to a basal promoter.  
     
     
         35 . The method of  claim 34 , wherein said basal promoter is PGK1, ADH1, GAL1-10, tet-R, MET25, CYC1 or CUP1.  
     
     
         36 . The method of  claim 21 , wherein said gene expression is measured by assaying the protein level of the expressed gene.  
     
     
         37 . The method of  claim 21 , wherein said gene expression is measured by assaying the RNA level of the expressed gene.  
     
     
         38 . The method of  claim 21 , further comprising determining whether said candidate compound increases the production of a secondary metabolite in a fungus.  
     
     
         39 . A method for determining whether a candidate compound inhibits fungal invasion, said method comprising 
 (a) contacting a fungus with a candidate compound under conditions suitable for invasion; and    (b) measuring or detecting invasion by said fungus following contact with said candidate compound.    
     
     
         40 . The method of  claim 39 , wherein said fungus is  Candida albicans.    
     
     
         41 . The method of  claim 39 , wherein said fungus is  Saccharomyces cerevisiae.    
     
     
         42 . A method for determining whether a candidate compound promotes fungal invasion, said method comprising 
 (a) contacting a fungus with a candidate compound under conditions suitable for invasion; and    (b) measuring or detecting invasion by said fungus following contact with said candidate compound.    
     
     
         43 . The method of  claim 42 , wherein said fungus is  Candida albicans.    
     
     
         44 . The method of  claim 42  wherein said fungus is  Saccharomyces cerevisiae.    
     
     
         45 . The method of  claim 42 , wherein said fungus is  Aspergillus nidulans.    
     
     
         46 . A method for identifying a fungal invasion-promoting gene, said method comprising 
 (a) expressing in a fungus (i) a first gene operably linked to a fungal invasin gene promoter and (ii) a second candidate gene or a fragment thereof; and    (b) monitoring, the expression of said first gene,    wherein an increase in said expression identifies said candidate gene as a fungal invasion-promoting gene.    
     
     
         47 . The method of  claim 46 , wherein said fungus is a wild-type strain.  
     
     
         48 . The method of  claim 47 , wherein said wild-type strain is  Saccharomyces cerevisiae.    
     
     
         49 . The method of  claim 46 , wherein said fungus is a mutant strain.  
     
     
         50 . The method of  claim 46 , wherein said fungus is a transgenic fungus  
     
     
         51 . The method of  claim 46 , wherein said first gene comprises a fungal invasin gene.  
     
     
         52 . The method of  claim 51 , wherein said fungal invasin gene is FLO11 or MUC1.  
     
     
         53 . The method of  claim 51 , wherein said fungal invasin gene is AFL1, DHH1, INV1, INV5, INV6, INV7, INV8, INV9, INV10, INV11, INV12, INV13, INV14, INV15, BEM2, CDC25, HOG1, IRA1, RIM1, MCM1, MGA1, PET9, PHD2, PHO23, PTC1, RIM15, SFL1, SRB11, SSD1, STE21, STP22, SWI4, TPK2, TPK3, or YPR1  
     
     
         54 . The method of  claim 46 , wherein said first gene comprises a reporter gene.  
     
     
         55 . The method of  claim 54 , wherein said reporter gene is lacZ, URA3, or HIS3.  
     
     
         56 . The method of  claim 46 , wherein said fungal invasin gene promoter is the FLO11, MUC1, STA1, STA2, or STA3 gene promoter.  
     
     
         57 . The method of  claim 46 , wherein said fungal invasin gene promoter is the AFL1, DHH1, INV1, RIM1, INV5, INV6, INV7, INV8, INV9, INV10, INV11, INV12, INV13, INV14, INV15, BEM2, CDC25, HOG1, IRA1, MCM1, MGA1, PET9, PHD2, PHO23, PTC1, RIM15, SFL1, SRB11, SSD1, STE21, STP22, SWI4, TPK2, TPK3, or YPR1 gene promoter.  
     
     
         58 . The method of  claim 46 , wherein said fungal invasin gene promoter is a fragment or deletion of the FLO11, MUC1, STA1, STA2, or STA3 gene promoter.  
     
     
         59 . The method of  claim 58 , wherein said fragment is fused to a basal promoter.  
     
     
         60 . The method of  claim 59 , wherein said basal promoter is PGK1, ADH1, GAL1-10, tet-R, MET25, CYC1 or CUP1.  
     
     
         61 . The method of  claim 46 , wherein said gene expression is measured by assaying the protein level of the expressed first gene.  
     
     
         62 . The method of  claim 46 , wherein said gene expression is measured by assaying the RNA level of the expressed first gene.  
     
     
         63 . The method of  claim 46 , wherein said fungal invasion-promoting gene comprises a member of an invasin pathway.  
     
     
         64 . A method for identifying a fungal invasion-inhibiting gene, comprising 
 (a) expressing in a fungus (i) a first gene operably linked to a fungal invasin gene promoter and (ii) a second candidate gene or fragment thereof; and    (b) monitoring the expression of said first gene,    wherein a decrease in said expression identifies said candidate gene as a fungal invasion-inhibiting gene.    
     
     
         65 . The method of  claim 64 , wherein said fungus is a wild-type strain.  
     
     
         66 . The method of  claim 65 , wherein said wild-type strain is  Saccharomyces cerevisiae.    
     
     
         67 . The method of  claim 64 , wherein said fungus is a mutant strain.  
     
     
         68 . The method of  claim 64 , wherein said fungus is a transgenic fungus  
     
     
         69 . The method of  claim 64 , wherein said first gene comprises a fungal invasin gene.  
     
     
         70 . The method of  claim 69 , wherein said fungal invasin gene is FLO11 or MUC1.  
     
     
         71 . The method of  claim 69 , wherein said fungal invasin gene is AFL1, DHH1, INV1, INV5, INV6, INV7, INV8, INV9, INV10, INV11, INV12, INV13, INV14, RIM1, INV15, BEM7, CDC25, HOG1, IRA1, MCM1, MGA1, PET9, PHD2, PHO23, PTC1, RIM15, SFL1, SRB11, SSD1, STE21, STP22, SWI14, TPK2, TPK3, or YPR1  
     
     
         72 . The method of  claim 64 , wherein said first gene comprises a reporter gene.  
     
     
         73 . The method of  claim 72 , wherein said reporter gene is lacZ, URA3, or HIS3.  
     
     
         74 . The method of  claim 64 , wherein said fungal invasin gene promoter is the FLO11, MUC1, STA1, STA2, or STA3 gene promoter.  
     
     
         75 . The method of  claim 64 , wherein said fungal invasin gene promoter is the AFL1, DHH1, INV1, INV5, INV6, INV7, INV8, INV9, INV10, INV11, INV12, INV13, INV14, INV15, BEM2, CDC25, HOG1, IRA1, MCM1, MGA1, PET9, PHD2, PHO23, PTC1, RIM15, SFL1, SRB11, SSD1, STE21, STP22, SWI4, TPK2, TPK3, or YPR1 gene promoter.  
     
     
         76 . The method of  claim 64 , wherein said fungal invasin gene promoter is a fragment or deletion of the FLO11, MUC1, STA1, STA2, or STA3 gene promoter.  
     
     
         77 . The method of  claim 76 , wherein said fragment is fused to a basal promoter.  
     
     
         78 . The method of  claim 77 , wherein said basal promoter is PGK1, ADH1, GAL1-10, tet-R, MET25, CYC1 or CUP1.  
     
     
         79 . The method of  claim 64 , wherein said gene expression is measured by assaying the protein level of the expressed first gene.  
     
     
         80 . The method of  claim 64 , wherein said gene expression is measured by assaying the RNA level of the expressed first gene.  
     
     
         81 . The method of  claim 64 , wherein said fungal invasion-inhibiting gene comprises a member of an invasin pathway.  
     
     
         82 . A method for increasing production of a secondary metabolite in a fungal cell, said method comprising the step of contacting said fungal cell with a fungal invasion-promoting compound.  
     
     
         83 . A method for increasing production of a secondary metabolite in a fungal cell, said method comprising the step of decreasing the expression of a fungal invasion-inhibiting gene.  
     
     
         84 . The method of  claim 83 , wherein said decreased expression of said fungal invasion-inhibiting gene results from an inactivation of said fungal invasion-inhibiting gene.  
     
     
         85 . The method of  claim 83 , wherein said fungal invasion-inhibiting gene is mutated.  
     
     
         86 . The method of  claim 83 , wherein said fungal invasion-inhibiting gene comprises HOG1, BEM2, RIM15, SFL1, IRA1, SSD1, SRB11, SWI4, or TPK3.  
     
     
         87 . A method for increasing production of a fungal secondary metabolite, said method comprising the step of increasing the expression of a fungal invasion-promoting gene.  
     
     
         88 . The method of  claim 87 , wherein said fungal invasion-promoting gene is AFL1, DHH1, INV7, INV8, STE21, PET9, MEP2, INV1, INV5, INV6, INV9, INV10, INV11, INV12, INV13, INV14, INV15, CDC25, MCM1, MGA1, PHD2, PHO23, PTC1, RIM1, STP22, TPK2, or YPR1.  
     
     
         89 . The method of  claim 87 , wherein said fungal invasion-promoting gene is constitutively expressed or overexpressed.  
     
     
         90 . The method of  claim 87 , wherein said fungal invasion-promoting gene is mutated.  
     
     
         91 . A method for increasing production of a fungal secondary metabolite, said method comprising the step of expressing a gene, or fragment thereof, that encodes an activated form of a invasion-promoting polypeptide.  
     
     
         92 . The method of  claim 91 , wherein said activated form of said invasion-promoting polypeptide comprises a fusion between the invasion-promoting polypeptide and a second polypeptide that further enhances the activity of said invasion-promoting polypeptide.  
     
     
         93 . The method of  claim 91 , wherein said gene has a mutation.  
     
     
         94 . A method for increasing production of a secondary metabolite in a fungal cell, said method comprising the step of decreasing the activity of a fungal invasion-inhibiting polypeptide.  
     
     
         95 . The method of  claim 94 , wherein said fungal invasion-inhibiting polypeptide has a mutation.  
     
     
         96 . The method of  claim 95 , wherein said mutation encodes a dominant-inactive polypeptide.  
     
     
         97 . The method of  claim 94 , wherein said fungal invasion-inhibiting polypeptide comprises Hog1, Bem2, Rim15, Ira1, Sfl1, Ssd1, Srb11, Swi4, or Tpk3.  
     
     
         98 . A method for increasing production of a fungal secondary metabolite, said method comprising the step of increasing the activity of a fungal invasion-promoting polypeptide.  
     
     
         99 . The method of  claim 98 , wherein said fungal invasion-promoting polypeptide has a mutation.  
     
     
         100 . The method of  claim 99 , wherein said mutation encodes a dominant-active polypeptide.  
     
     
         101 . The method of  claim 98 , wherein said fungal invasion-promoting polypeptide is Afl1, Dhh1, Inv1, Inv5, Inv6, Inv9, Inv10, Inv11, Inv12, Inv13, Inv14, Rim1, Inv15, Cdc25, Inv7, Mcm1, Mga1, Phd2, Pho23, Ptc1, Inv8, Ste2, Pet9, Mep2, Stp22, Tpk2, or Ypr1.  
     
     
         102 . A method of isolating a fungal invasin gene, said method comprising 
 (a) providing a fungus expressing a genie operably linked to a fungal invasin gene promoter;    (b) mutagenizing said fungus;    (c) measuring expression of the gene, wherein an increase or decrease in the expression of said gene identifies a mutation in said invasin gene; and    (d) using said mutation as a marker for isolating said invasin gene.    
     
     
         103 . The method of  claim 102 , wherein said fungus is a wild-type strain.  
     
     
         104 . The method of  claim 103 , wherein said wild-type strain is  Saccharomyces cerevisiae.    
     
     
         105 . The method of  claim 102 , wherein said fungus is a mutant strain.  
     
     
         106 . The method of  claim 102 , wherein said gene comprises a fungal invasin gene.  
     
     
         107 . The method of  claim 106 , wherein said fungal invasin gene is FLO11 or MUC1.  
     
     
         108 . The method of  claim 106 , wherein said fungal invasin gene is AFL1, DHH1, INV1, INV5, INV6, INV7, INV8, INV9, INV10, INV11, INV12, INV13, INV14, INV15, BEM2, CDC25, HOG1, IRA1, MCM1, MGA1, PET9, PHD2, PHO23, RIM1, PTC1, RIM15, SFL1, SRB11, SSD1, STE21, STP22, SWI4, TPK2, TPK3, or YPR1  
     
     
         109 . The method of  claim 102 , wherein said gene comprises a reporter gene.  
     
     
         110 . The method of  claim 109 , wherein said reporter gene is lacZ, URA3, or HIS3.  
     
     
         111 . The method of  claim 102 , wherein said fungal invasin gene promoter is the FLO11, MUC1, STA1, STA2, or STA3 gene promoter.  
     
     
         112 . The method of  claim 102 , wherein said fungal invasin gene promoter is the AFL1, DHH1, INV1, INV5, INV6, INV7, INV8, INV9, INV10, INV11, INV12, INV13, INV14, INV15, BEM2, CDC25, RIM1, HOG1, IRA1, MCM1, MGA1, PET9, PHD2, PHO23, PTC1, RIM15, SFL1, SRB11, SSD1, STE21, STP22, SWI4, TPK2, TPK3, or YPR1 gene promoter.  
     
     
         113 . The method of  claim 102 , wherein said fungal invasin gene promoter is a fragment or deletion of the FLO11, MUC1, STA1, STA2, or STA3 gene promoter.  
     
     
         114 . The method of  claim 113 , wherein said fragment is fused to a basal promoter.  
     
     
         115 . The method of  claim 114 , wherein said basal promoter is PGK1, ADH1, GAL1-10, tet-R, MET25, CYC1 or CUP1.  
     
     
         116 . The method of  claim 102 , wherein said gene expression is measured by assaying the protein level of the expressed gene.  
     
     
         117 . The method of  claim 102 , wherein said gene expression is measured by assaying the RNA level of the expressed gene.  
     
     
         118 . A method of using a heterologous cell for identifying a gene which regulates the expression from a  Candida albicans  gene promoter, said method comprising 
 (a) providing a heterologous cell expressing a reporter gene operably linked to a  Candida albicans  gene promoter;    (b) expressing a candidate gene in said heterologous cell; and    (c) detecting or measuring said expression of said reporter gene.    
     
     
         119 . The method of  claim 118 , wherein said heterologous cell is  Saccharomyces cerevisiae.    
     
     
         120 . A method for preparing a transgenic fungal cell having increased secondary metabolite production, said method comprising 
 (a) introducing a transgene into a fungal cell; and    (b) selecting a cell that expresses the transgene to produce a protein, wherein said transgene is AFL1, DHH1, INV7, INV8, STE21, , PET9, MEP2, INV1, INV5, INV6, INV9, INV10, INV11, RIM1, INV12, INV13, INV14, INV15, CDC25, MCM1, MGA1, PHD2, PHO23, PTC1, STP22, TPK2, YPR1, HOG1, BEM2, RIM15, SFL1, IRA1, SSD1, SRB11, SWI4, TPK3, or a fragment thereof.    
     
     
         121 . The method of  claim 120 , wherein said transgene has a mutation.  
     
     
         122 . The method of  claim 121 , wherein said mutation is a dominant-active mutation.  
     
     
         123 . The method of  claim 121 , wherein said mutation is a dominant-inactive mutation.  
     
     
         124 . A method for increasing a secondary metabolite in a fungus, said method comprising 
 (a) culturing said fungus in culture with conditions allowing for secondary metabolite production;    (b) adding to said culture a fungal invasion-promoting compound; and    (c) isolating said metabolite from said culture.    
     
     
         125 . The method of  claim 124 , wherein said fungus has a mutation.  
     
     
         126 . The method of  claim 124 , wherein said fungus is a wild-type strain.  
     
     
         127 . A transgenic filamentous fungus comprising a mutation in its HOG1 gene, said mutation inhibits the activity of a functional Hog1 protein.  
     
     
         128 . The transgenic filamentous fungus of  claim 127 , wherein said fungus has increased secondary metabolite production.  
     
     
         129 . A transgenic filamentous fungus comprising a mutation in its SWI4 gene, said mutation inhibits the activity of a functional Swi4 protein.  
     
     
         130 . The transgenic filamentous fungus of  claim 129 , wherein said fungus has increased secondary metabolite production.  
     
     
         131 . A transgenic filamentous fungus comprising a mutation in its BEM2 gene, said mutation inhibits the activity of a functional Bem2 protein.  
     
     
         132 . The transgenic filamentous fungus of  claim 131 , wherein said fungus has increased secondary metabolite production.  
     
     
         133 . A transgenic filamentous fungus comprising a mutation in its SRB11 gene, said mutation inhibits the expression of a functional Srb11 protein.  
     
     
         134 . The transgenic filamentous fungus of  claim 133 , wherein said fungus has increased secondary metabolite production.  
     
     
         135 . A transgenic filamentous fungus comprising a mutation in its SSD1 gene, said mutation inhibits the expression of a functional Ssd1 protein.  
     
     
         136 . The transgenic filamentous fungus of  claim 135 , wherein said fungus has increased secondary metabolite production.  
     
     
         137 . A transgenic filamentous fungus comprising a mutation in its TPK3 gene, said mutation inhibits the expression of a functional Tpk3 protein.  
     
     
         138 . The transgenic filamentous fungus of  claim 137 , wherein said fungus has increased secondary metabolite production.  
     
     
         139 . A transgenic filamentous fungus comprising a mutation in its SFL1 gene, said mutation inhibits the expression of a functional Sfl1 protein.  
     
     
         140 . The transgenic filamentous fungus of  claim 139 , wherein said fungus has increased secondary metabolite production.  
     
     
         141 . A transgenic filamentous fungus comprising a mutation in its IRA1 gene, said mutation inhibits the expression of a functional Ira1 protein.  
     
     
         142 . The transgenic filamentous fungus of  claim 141 , wherein said fungus has increased secondary metabolite production.  
     
     
         143 . A substantially pure preparation of an Inv9 polypeptide.  
     
     
         144 . The Inv9 polypeptide of  claim 143 , wherein said Inv9 polypeptide is at least 55% identical to the amino acid sequence of FIG. 6B (SEQ ID NO:6).  
     
     
         145 . The polypeptide of  claim 143 , wherein said Inv9 polypeptide is from a fungus.  
     
     
         146 . The polypeptide of  claim 145 , wherein said fungus is a yeast.  
     
     
         147 . The polypeptide of  claim 145 , wherein said yeast is  Saccharomyces cerevisiae.    
     
     
         148 . The polypeptide of  claim 143 , wherein said polypeptide has invasion promoting activities.  
     
     
         149 . Isolated DNA encoding an Inv9 polypeptide.  
     
     
         150 . The DNA of  claim 149 , wherein said DNA comprises an INV9 gene of FIG. 6A (SEQ ID NO: 5).  
     
     
         151 . The DNA of  claim 149 , wherein said DNA complements an INV9 mutation in  Saccharomyces cerevisiae.    
     
     
         152 . A vector comprising the isolated DNA of  claim 149 , said vector being capable of directing the expression of the protein encoded by said DNA in a vector-containing cell.  
     
     
         153 . A cell comprising the vector of  claim 152.