Expression of lactate dehydrogenases A and B during chicken spermatogenesis: characterization of testis specific transcripts.

The substrates required for glycolysis change markedly at successive stages of spermatogenesis suggesting a considerable plasticity in the expression of glycolytic enzymes. Lactate dehydrogenase (LDH) isoenzymes, LDH-A and LDH-B, are expressed in premeiotic, meiotic cells, and early spermatids, both in avian and mammalian spermatogenesis. Highly polyadenylated forms, particularly of LDH-A, were detected in chicken testis. While mammals and columbid birds express the testis specific LDH-C gene in meiotic and postmeiotic cells, several LDH-B testis specific transcripts were detected in the corresponding cells during chicken spermatogenesis. These testis specific transcripts and the mRNA of mammalian LDH-C show several properties in common, such as temporal correlation of expression, mRNA stability, and repression of premature translation. These observations suggest that the testis specific transcripts could perform during chicken spermatogenesis the functions of the LDH-C mRNA in mammalian testis.