Sequence analysis of teleost retina-specific lactate dehydrogenase C: evolutionary implications for the vertebrate lactate dehydrogenase gene family.

Abstract

At least two gene duplication events have led to the three lactate dehydrogenase (LDH; EC 1.1.1.27) isozymes (LDH-A, LDH-B, and LDH-C) of chordates. The prevailing model for the evolution of the LDH loci involves duplication of a primordial LDH locus near the origin of vertebrates, giving rise to Ldh-A and LU-B. A third locus, designated Ldh-C, is expressed in the spermatocytes of mammals and a single family of birds and in the eye or liver tissues of teleost fishes. Ldh-C might have arisen independently in these taxa as duplications of either Ldh-A or Ldh-B. Several authors have challenged this traditional hypothesis on the basis of amino acid sequence and immunological similarity of the three LDH isozymes. They suggest that the primordial LDH gene was duplicated to form Lk-C and a locus that later gave rise to Ldh-A and Lk-B. We have differentiated between these hypotheses by determining the cDNA sequence of the retinaspecific LDH-C from a teleost, Fundulus heteroclitus. On the basis of amino acid sequence similarity, we conclude that the LDH-C isozymes in fish and mammals are not orthologous but derive from independent gene duplications. Furthermore, our phylogenetic analyses support previous hypotheses that teleost LUh-C is derived from a duplication of the LU-B locus.Many workers have emphasized the importance of gene duplication as a mechanism of evolution and biological diversification (e.g., refs.

From Gene to Organismal Phylogeny: Reconciled Trees and the Gene Tree/Species Tree Problem

“…13 shows that the letters ''A,'' ''B,'' and ''C'' do not correspond exactly to orthologous sequences, as noted by Quattro et al (1993). Therefore the homology of these sequences must be reconsidered.…”

“…Other mammalian phylogenies may alter the interpretation of which sequences were orthologous or paralogous. As a final example of the application of reconciled trees we shall use lactate dehydrogenase (LDH), which was briefly discussed by Page (1994) based on data from Quattro et al (1993). Although Tsuji et al (1994) have since published a larger LDH tree we shall persist in using Quattro et al's tree as its smaller size makes it more manageable.…”

Fundulus as the premier teleost model in environmental biology: Opportunities for new insights using genomics

“…There are even suggestions that killifish possess the ability to change color in response to background color. In addition, the eye and its many complex components, such as the retina, have been the source of discovery of unique gene isoforms, including a F. heteroclitus retinal specific lactate dehydrogenase-C (Ldh-C) isoform (Quattro et al, 1993). …”

Biochemical Properties of Lactate Dehydrogenase Eye-Specific C4Isozyme: Lepomis macrochirus and Micropterus salmoides

“…그리고 눈조직에서 발현되는 LDH eye-specific C4는 망막 의 광수용기 세포에 존재하여 광색소 재생성에 필요한 NAD + 를 생성할 수 있다고 제시되어 [33,46], 농어목 어류에서 보고되 었고 [47], cichlidae 어류의 눈 및 뇌조직에서 eye-specific Ldh-C가 확인되었으며 [17], 송어에서 피루브산에 대해 친화성 이 크게 자연 선택되었다고 보고되었다 [19]. 그리고 lactate shuttle에 의한 젖산의 중요성이 인식되면서 망막에서의 젖산 대사와 monocarboxylate 수송체(monocarboxylate transporters, MCT)에 대한 연구가 진행되고 있으나 [5] LDH와 관 련된 연구는 이루어지고 있지 않다.…”