Unusual retrotransposon from the yeast Candida albicans

Abstract

TCa2 is a TyI/copia retrotransposon from the pathogenic yeast Candida albicans . In contrast to other retrotransposons it can appear as an abundant, extrachromosomal double-stranded DNA molecule, called pCal. The invention relates to the isolation and characterisation of TCa2 and pCal together with its uses for inducing random mutagenesis in a genome, as a component of a transposable element and of an expression vector.

1 - 14 . (canceled)  
     
     
         15 . A method of gene disruption or altered expression comprising integrating a retrotransposon selected from the group consisting of: 
 (a) an isolated retrotransposon consisting of SEQ ID NO:3: and    (b) an isolated and purified retrotransposon comprising a nucleotide sequence that has at least 95% sequence similarity with a nucleotide sequence selected from the group consisting of: 
 (i) SEQ ID NO:3; and  
 (ii) the LTR and POL region of SEQ ID NO:3, into a site or sites in a yeast or fungus or  Candida , wherein the retrotransposon contains elements that cause gene disruption or altered expression at the site or sites.  
   
     
     
         16 . A gene discovery method comprising 
 integrating a retrotransposon selected from the group consisting of:    (a) an isolated retrotransposon consisting of SEQ ID NO:3; and    (b) an isolated and purified retrotransposon comprising a nucleotide sequence that has at least 95% sequence similarity with a nucleotide sequence selected from the group consisting of: 
 (i) SEQ ID NO:3; and  
 (ii) the LTR and POL region of SEQ ID NO:3, into a site or sites in a yeast or fungus or  Candida , wherein the retrotransposon contains elements that cause gene disruption or altered expression at the site or sites; and,  
   mapping the gene or genes disrupted or whose expression has been altered by the retrotransposon.    
     
     
         17 - 24 . (canceled)  
     
     
         25 . A method for gene disruption or altered expression comprising disrupting a gene by active retrotransposition into a new site or sites in the  Candida  genome of a retrotransposon.  
     
     
         26 . A method for discovering a gene comprising disrupting a gene by active retrotransposition into new site or sites in the  Candida  genome of a retrotransposon; and mapping the gene disrupted.  
     
     
         27 - 32 . (canceled)  
     
     
         33 . The method of  claim 15 , wherein the gene disruption or altered expression is non-revertible.  
     
     
         34 . The method of  claim 16 , wherein the gene disruption or altered expression is non-revertible.  
     
     
         35 . The method of  claim 25 , wherein the gene disruption or altered expression is non-revertible.  
     
     
         36 . The method of  claim 26 , wherein disruption of the gene is non-revertible.