Three genes for the elongation factor EF-1 alpha in Mucor racemosus.

We cloned three genes from Mucor racemosus coding for protein synthesis elongation factor 1 alpha (EF-1 alpha). A 110-base-pair (bp) EF-1 alpha-specific cDNA clone was identified by hybrid-selected translation. The nucleotide sequence of the cDNA showed significant homology to a region of the Saccharomyces cerevisiae genes for EF-1 alpha (TEF1 and TEF2). The cDNA was used to isolate an 850-bp EcoRI genomic DNA fragment containing a portion of the EF-1 alpha gene. Screening of a lambda/M. racemosus genomic DNA bank with the 850-bp EcoRI probe resulted in the identification of three DNA fragments containing a common 850-bp EcoRI fragment within a short overlapping region. S1 nuclease analysis of the three EF-1 alpha DNA fragments showed that the EF-1 alpha transcript covered the short overlapping region in the clones. Restriction fragments purified from flanking regions in each clone were used to probe a HindIII digest of M. racemosus genomic DNA. Each flanking probe hybridized to one of three DNA fragments which hybridized to the 850-bp EF-1 alpha-specific probe. Nucleotide sequence data from two random "shotgun clones" of one of the three genes show good homology to two regions of S. cerevisiae TEF1. The data indicate the presence of three genes for EF-1 alpha in M. racemosus located at unique sites in the genome.