GENOMIC STRUCTURE AND PROMOTER ACTIVITY OF THE HUMAN TESTIS LACTATE-DEHYDROGENASE GENE

The structure of the gene encoding the human testis-specific isozyme o f lactate dehydrogenase (LDH) has been characterized and a regulatory region identified by promoter activity. The single-copy ldh-c gene has two alternative 5' noncoding exons and seven coding exons comprising an approximately 40-kb locus. The gene does not contain the canonical TATA or CAAT promoter sequences, and ribonuclease protection experimen ts suggest multiple transcription start sites. In the present study an immortalized murine germ cell line was used to detect promoter activi ty driven by 5' sequence of human ldh-c with lacZ as the reporter gene . Reporter gene activity was nondetectable when promoter constructs we re transfected into nongerminal cells.