NCBI Summary:
Lactate dehydrogenase C catalyzes the conversion of L-lactate and NAD to pyruvate and NADH in the final step of anaerobic glycolysis. LDHC is testis-specific and belongs to the lactate dehydrogenase family. Two transcript variants have been detected which differ in the 5' untranslated region.
General function
Enzyme
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Cellular localization
Cytoplasmic
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Ovarian function
Oogenesis
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Identification of developmental competence-related genes in mature porcine oocytes. Yuan Y et al. Oocyte competence is a key factor limiting female fertility, yet the underlying molecular mechanisms that contribute to oocyte competence remain unclear. The objective of this study was to elucidate specific genes whose function contributes to oocyte competence. We observed that 6 of 20 target genes examined were differentially expressed between adult (more competent) and prepubertal (less competent) porcine in vitro matured (IVM) oocytes. These genes were the cholesterol synthesis-related gene HMG-CoA reductase (HMGCR), fatty acid oxidation genes acyl-CoA synthetase long-chain family member 3 (ACSL3) and long-chain acyl-CoA dehydrogenase (ACADL), glycolytic genes fructose 1,6 bisphosphate aldolase (ALDOA) and lactate dehydrogenase C (LDHC), and tumor necrosis factor-a (TNF). These 6 genes, as well as 3 other genes [porcine endogenous retrovirus (PERV), transcribed loci 10 (TL10), serine/arginine-rich splicing factor 1 (SRSF1)], were further analyzed by comparing transcript abundance in IVM and in vivo matured (VVM) prepubertal and adult porcine oocytes. Among these 9 target genes, 5 were differentially expressed between IVM and VVM prepubertal oocytes, while 8 genes were differentially expressed between IVM and VVM adult oocytes. No genes were differentially expressed between VVM prepubertal and adult oocytes. A functional study of TNF demonstrated that depletion of endogenous TNF decreased oocyte competence and TNFAIP6 expression in cumulus cells, while TNF in IVM medium regulated TNFAIP6 expression in cumulus cells. Differential expression of the genes identified in this study suggests that these genes may be functionally relevant to oocyte competence. Mol. Reprod. Dev. 2011 Wiley-Liss, Inc.
Expression regulated by
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Ovarian localization
Oocyte
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Testis-Specific Lactate Dehydrogenase (LDH-C4; Ldh3) in Murine Oocytes and Preimplantation Embryos. Coonrod S et al. LDH-C4 (Ldh3) is a member of the lactate dehydrogenase family of isozymes that catalyze the terminal reaction in the glycolytic pathway. In mammals three genes, ldha, ldhb, and Ldhc encode the subunits that assemble into catalytically active homo- and heterotetramers. Differential expression of these genes determines the LDH isozyme composition of tissues and as is well known, A subunits predominate in skeletal muscle and B subunits are abundantly produced in brain and heart with the Ldh2 isozyme the most abundant form in oocytes. The C peptide can be detected first in pachytene spermatocytes and constitutes the primary LDH of spermatozoa. Originally the Ldhc gene (Ldh3 in terminology applied to murine cells) was considered to be testis-specific on the basis of immunochemical, enzymatic and molecular analyses. Here we report the detection of this isozyme in the murine oocyte and early embryo. Our results indicate that Ldh3 mRNA is transcribed in oocytes, and cannot be detected in fertilized eggs. Ldh3 protein, however, persists to the blastocyst stage of embryonic development localizing mainly to the cortex region of oocytes, eggs, zygotes and embryonic blastomeres.