RIM2, MSI1 and PGI1 are 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.

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.