Identification of a novel human lactate dehydrogenase gene LDHAL6A, which activates transcriptional activities of AP1(PMA).

L-lactate dehydrogenase is a crucial enzyme in the process of glycolysis. Here we report the cloning and characterization of another novel lactate dehydrogenase gene, named as LDHAL6A (lactate dehydrogenase A-like 6A), which encodes a 332-amino-acid protein. The LDHAL6A gene consists of seven exons, and is mapped to 11p15.1 by searching the UCSC genomic database. By RT-PCR analysis in various tissues, LDHAL6A was found to be exclusively expressed in human testis. Subcellular localization demonstrated that LDHAL6A protein was located in the cytoplasm when overexpressed in COS7 cells. Furthermore, we found that the recombinant protein GST-LDHAL6A can catalyze the pyruvate convert into the lactate with NADH as its coenzyme. And in the dual luciferase reporter system, expression of LDHAL6A was able to activate transcriptional activities of AP1(PMA).