FUNCTIONAL-ANALYSIS OF 3 ADJACENT OPEN READING FRAMES FROM THE RIGHT ARM OF YEAST - CHROMOSOME XVI

A 7.24 kb genomic DNA fragment from the yeast Saccharomyces cerevisiae chromosome XVI was isolated by complementation of a new temperature-s ensitive mutation tsa1. We determined the nucleotide sequence of this fragment located on the right arm of chromosome XVI. Among the three, complete open reading frames: YPR041w, YPR042c and YPR043w contained w ithin this fragment, the gene YPR041w was shown to complement the tsa1 mutation and to correspond to the TIF5 gene encoding an essential pro tein synthesis initiation translation factor. The YPR042c gene encodes a hypothetical protein of 1075 amino acids containing four putative t ransmembrane segments and is non-essential for growth. The gene YPR043 c encoding the 10 kDa product, highly similar to the human protein L37 a from the 60S ribosomal subunit, was found to be essential and a domi nant lethal. We conclude that three tightly linked yeast genes are inv olved in the translation process. (C) 1998 John Wiley & Sons, Ltd.