Sequence analysis of the CEN12 region of Saccharomyces cerevisiae on a 43.7 kb fragment of chromosome XII including an open reading frame homologous to the human cystic fibrosis transmembrane conductance regulator protein CFTR.

In the framework of the European Union BIOTECH project for systematically sequencing the Saccharomyces cerevisiae genome, we determined the nucleotide sequence of a 43.7 kb DNA fragment spanning the centromeric region of chromosome XII. A novel approach was the distribution of sublibraries prepared by the DNA coordinator (J. Hoheisel, Heidelberg, FRG), using a new hybridization-based DNA mapping method, in order to facilitate ordered sequencing. The sequence contains 22 open reading frames (ORFs) longer than 299 bp, including the published sequences for ATS/DPS1, SCD25, SOF1, DRS1, MMM1, DNM1 and the centromeric region CEN12. Five putative ORF products show similarity to known proteins: the leucine zipper-containing ABC transporter L1313p to the yeast Ycflp metal resistance protein, to the yeast putative ATP-dependent permease Yhd5p, to the yeast putative proteins Yk83p and Yk84p, to the human cystic fibrosis transmembrane conductance regulator protein (hCFTR) and to the human multidrug resistance-associated protein hMRP1; L1325p to the Drosophila melanogaster Pumilio protein, to the putative yeast regulatory protein Yg13p and to the yeast protein Mpt5p/Htrlp; L1329p to human lipase A and gastric lipase, to rat lingual lipase and to the putative yeast triglyceride lipase Tg11p; L1341p to the putative yeast protein Yhg4p; and the leucine zipper-containing L1361p to the two yeast proteins 00953p and Ym8156.08p and to the Arabidopsis thaliana protein HYP1. Eight ORFs show no homology to known sequences in the database, three small ORFs are internal and complementary to larger ones and L1301 is complementary overlapping the ATS/DPS1 gene. Additionally three equally spaced ARS consensus sequences were found.