title: Evolutionary relations among vertebrate muscle-type lactate dehydrogenases.
abstract: Gene duplication has produced two lactate dehydrogenase (LDH) isozymes, LDH-A and LDH-B, that are found in essentially all vertebrates. On the basis of the biochemical properties of the LDH-A and LDH-B isozymes, it has been suggested that each locus is orthologous among all vertebrates. However, phylogenetic studies have not supported a common evolutionary history among the LDH-A isozymes, particularly when those from lower vertebrates are examined. We present here the sequence of a muscle-type LDH from Fundulus heteroclitus, a teleost fish for which the LDH-B sequence has been determined and shown to be unrelated phylogenetically to tetrapod LDH-A isozymes. Although the sequence of the teleost muscle LDH shares certain features with the LDH-A of tetrapods, phylogenetic analyses do not support an orthologous relation among the LDH-A isozymes of teleost fish and tetrapod vertebrates.
authors.affiliation: Department of Biology, University of South Carolina, Columbia 29208, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Quattro
authors.forename: D D
authors.initials: DD
authors.lastname: Pollock
authors.forename: M
authors.initials: M
authors.lastname: Powell
authors.forename: H A
authors.initials: HA
authors.lastname: Woods
authors.forename: D A
authors.initials: DA
authors.lastname: Powers
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D005399:Fishes / Q000235:genetics; D015723:Gene Library; D006801:Humans; D007527:Isoenzymes; D007695:Killifishes / Q000235:genetics; D007770:L-Lactate Dehydrogenase / Q000235:genetics*; D008322:Mammals / Q000235:genetics; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000201:enzymology*; D010802:Phylogeny; D014714:Vertebrates / Q000235:genetics*
chemical_list: D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase