Scarcity of ars sequences isolated in a morphogenesis mutant of the yeast Yarrowia lipolytica.
Previous attempts is isolate autonomously replicating sequences (ars) from the dimorphic yeast Yarrowia lipolytica have been unsuccessful. We isolated a Fil- mutant unable to produce hyphae and growing only in a yeast form to facilitate ars isolation. This mutant was transformed with a Y. lipolytica DNA bank and several unstable clones were obtained. Extrachromosomal plasmids were evidenced in yeast, recovered in Escherichia coli and characterized by restriction mapping. They were able to retransform Fil- and Fil+ yeast strains at high frequency and transformants displayed a slightly unstable phenotype. The detailed analysis of the plasmids showed that only two different ars sequences had been isolated, each of them corresponding to a unique sequence in the Y. lipolytica genome. We concluded that functional ars sequences that can be cloned on plasmids are rare in this yeast.
Fournier
P
P
Lab. Génétique INRA, Centre de Biotechnologies Agro-Industrielles, Thiverval-Grignon, France.
Guyaneux
L
L
Chasles
M
M
Gaillardin
C
C
D001483:Base Sequence; D003001:Cloning, Molecular; D015342:DNA Probes; D004261:DNA Replication; D004271:DNA, Fungal / Q000032:analysis / Q000737:chemistry* / Q000235:genetics; D015723:Gene Library; D009154:Mutation; D010957:Plasmids; D015183:Restriction Mapping; D004718:Saccharomycetales / Q000235:genetics* / Q000254:growth & development; D014170:Transformation, Genetic; D015003:Yeasts / Q000235:genetics* / Q000254:growth & development
D015342:DNA Probes; D004271:DNA, Fungal