Functional analysis of eight open reading frames on chromosomes XII and XIV of Saccharomyces cerevisiae

Deletion, together with basic functional and bioinformatic analyses has been carried out on eight novel ORFs discovered during the sequencing of the Saccharomyces cerevisiae genome. Six ORFs (YLL049w, YLL051c, YLL052c, YLL053c, YLL054c and YLL055w) located on the left arm, and one (YLR130c) on the right arm, of chromosome XII, and an eighth ORF (YNL331c) on the left arm of the chromosome XIV, have been investigated. ORFs were deleted by the SFH-PCR gene-replacement strategy. Basic functional analysis revealed no obvious phenotype for any of the eight ORFs. Bioinformatic analysis, however, revealed possible functions for seven of the ORFs on the basis of the amino acid sequence similarity of their predicted protein products to those of proteins with known functions. ORF YLL051c (FRE6) shows similarity to iron transport proteins, such as ferric reductase. YLL052c and YLL053c appear to be aquaporins. The product of YLL054c (Yll054p) is highly similar to the oleate-specific transcriptional activator protein (Pip2p), which is involved in the peroxisomal induction pathway (pip). ORF YLL055w is similar to Dal5p, allantoate permease, and may play role in allantoin transport. YLR130c (ZRT2) is a low-affinity zinc transporter protein. YNL331c is also named AAD14, which is induced by chemicals that induce oxidative stress by depleting the cell of glutathione.