A PUTATIVE HELICASE, THE SUA5, PMR1, TRNA(LYS1) GENES AND 4 OPEN READING FRAMES HAVE BEEN DETECTED IN THE DNA-SEQUENCE OF AN 8.8 KB FRAGMENT OF THE LEFT ARM OF CHROMOSOME-VII OF SACCHAROMYCES-CEREVISIAE

We report the sequence of an 8.8 kb segment of DNA from the left arm o f chromosome VII of Saccharomyces cerevisiae. The sequence reveals sev en open reading frames (ORFs) G1651, G1654, G1660, G1663, G1666, G1667 and G1669 greater than 100 amino acids in length and the tRNA(Lys1) g ene. ORF G1651 shows 100% identity with the ROK1 protein which is a pu tative RNA helicase of the 'DEAD box' protein family. ORF G1654 exhibi ts a motif highly conserved in ATP/GTP binding proteins generally refe rred to as 'P-loop'. From FastA analysis, G1660 and G1666 were found t o be previously sequenced genes, respectively SUA5 and PMR1. The three other ORFs identified are partially (G1663) or completely (G1667 and G1669) overlapping with the PMR1 sequence on the complementary strand. This feature, together with their low codon adaptation indexes and th e absence of significant homology with known proteins suggest that the y do not correspond to real genes. The nucleotide sequence of the 8.8 kb fragment is available through the EMBL data library under the Acces sion Number X85757.