XDJ1, A GENE ENCODING A NOVEL NONESSENTIAL DNAJ HOMOLOG FROM SACCHAROMYCES-CEREVISIAE

The gene encoding a novel DnaJ-like protein, termed Xdj1, has been ide ntified by amplification of Saccharomyces cerevisiae genomic DNA. An o pen reading frame of 1380 bp was detected. Disruption of XDJ1 did not yield any detectable new phenotype. A double-deletion strain containin g a disruption of both XDJ1 and YDJ1, another gene coding for a DnaJ-l ike protein, was still viable. Under a variety of growth conditions, n o XDJ1 transcripts could be detected by Northern blot analysis and no translation product was found by immunoblotting with antibody against Xdj1 produced in Escherichia coli. Thus, XDJ1 is either expressed only under very specific conditions or represents a silent gene.