Testis-specific lactate dehydrogenase (LDH-C4; Ldh3) in murine oocytes and preimplantation embryos.
LDH-C(4) (Ldh3) is a member of the lactate dehydrogenase family of isozymes that catalyze the terminal reaction in the glycolytic pathway. In mammals, 3 genes, ldha, ldhb, and Ldhc, encode the subunits that assemble into catalytically active homo- and heterotetramers. Differential expression of these genes determines the lactate dehydrogenase (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.
Department of Genetic Medicine, Weill Medical College of Cornell University, New York, New York, USA.
Scott
S
Coonrod
Alejandra
A
Vitale
Chongwen
C
Duan
Sarah
S
Bristol-Gould
John
J
Herr
Erwin
E
Goldberg
D000595:Amino Acid Sequence; D000818:Animals; D001755:Blastocyst / Q000201:enzymology*; D005260:Female; D007527:Isoenzymes / Q000032:analysis; D007770:L-Lactate Dehydrogenase / Q000032:analysis*; D051379:Mice; D008969:Molecular Sequence Data; D009865:Oocytes / Q000201:enzymology*; D020543:Proteome / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction
D007527:Isoenzymes; D020543:Proteome; D007770:L-Lactate Dehydrogenase; C409677:lactate dehydrogenase 3; C409673:lactate dehydrogenase C4