RIM2, MSI1 and PGI1 and located within an 8 kb segment of Saccharomyces cerevisiae chromosome II, which also contains the putative ribosomal gene L21 and a new putative essential gene with a leucine zipper motif

Abstract

We report the DNA sequence of an 8 kb segment localized on the right arm of chromosome II from Saccharomyces cerevisiae. The sequence reveals the presence of eight open reading frames (ORFs). Three of them, YBR1402, YBR1405 and YBR1406 are previously sequenced genes, respectively the RIM2 (replication in mitochondria), MSI1 (multicopy suppressor of IRA1 gene) and PGI1 (phosphoglucoisomerase) genes. The predicted product of the ORF YBR1401 could be the putative yeast ribosomal protein L21. A new essential gene, YBR1403, has been identified by disruption; it possesses a leucine zipper motif.

SHM1: A multicopy suppressor of a temperature-sensitive null mutation in the HMG1-likeabf2 gene

“…Analysis of mitochondrial membrane fractions by carbonate (high pH) and detergent (Triton X-100) extraction suggests that SHMlp may be an integral membrane protein (data not shown). Interestingly, the deduced amino acid sequence of the RIM2 gene (Demolis et al, 1993), which was isolated as a low copy suppressor of the pijl mutant (Van Dyck et al, 1992a), also shows homology to the carrier proteins and to SHMlp (Klingenberg and Nelson, 1994). The PIFI gene encodes a yeast mitochondrial DNA helicase involved in mtDNA repair, recombination and stability (Foury and Kolodynski, 1983;Foury and Van Dyck, 1985;Foury and Lahaye, 1987;Lahaye et al, 1991) and the pijl null mutant is similar to the abJ2 mutant in having a temperature-sensitive phenotype (Van Dyck et al, 1992b).…”

The Med proteins of yeast and their function through the RNA polymerase II carboxy-terminal domain

“…The existence of a putative leucine zipper motif in MED8 at amino acids 69-90 has been recognized previously (Dé molis et al 1993). MED2 contains an asparagine-rich region at the carboxy terminus of >100 amino acids.…”

“…Med7 derived from an uncharacterized open reading frame. The Med8 band gave rise to peptide sequences from two open reading frames, one corresponding to the previously identified holoenzyme component Rox3 (Gustafsson et al 1997), and a second, equally abundant protein, from an open reading frame partially characterized in the yeast chromosome II sequencing effort (Dé molis et al 1993), for which we retain the designation Med8.…”

SDC25, a dispensable Ras guanine nucleotide exchange factor of Saccharomyces cerevisiae differs from CDC25 by its regulation.

“…Usually, amplification was done with 1 jig of genomic DNA or 10 ng of plasmid DNA by 1.5 ,u Taq-polymerase (Appligene, Heidleberg, Germany) in conditions described by the supplier, in a Perkin-Elmer 480 thermo-cycler apparatus (Norwalk, CT). Nucleotide sequences were determined on double-stranded DNA by automated DNA sequencing, as previously described (Demolis et al, 1993), using the "Prism Kit" (Applied Biosystems, Foster City, CA). The sequence of the 5' part of SDC25 gene on the pRG3 plasmid and on genomic DNA from strains OL136, W303, and FY1679 was done on amplimers generated by polymerase chain reaction (PCR) with the primers olSDC1648 and olSDC2220.…”