MOLECULAR STUDIES OF PET61, PET44 AND YKE2 GENES IN SACCHAROMYCES CEREVISIAE

Abstract

The Saccharomyces cerevisiae nuclear gene PET61 was identified. Sequence analysis of the genomic fragment in pG61/ST4 revealed two open reading frames (ORFs). A 780 bp ORF is responsible for the respiratory competency of the PET61 gene. Disruption of this gene created a stable pet phenotype. Another ORF, located downstream of the PET61 gene, is homologous to a mouse developmental gene KE2. Inactivation of YKE2 gene did not cause a respiratory defective phenotype. Disruption of the Saccharomyces cerevisiae nuclear gene PET44, caused decreased mitochondrial succinic dehydrogenase activity, and led to a respiratory defect and a loss of mitochondrial DNA. A novel method mediated by the polymerase chain reaction (PCR) to inactivate the YKE2 and PET44 gene was employed, as these two genes lacked convenient restriction sites within their coding regions.