Identification of yak lactate dehydrogenase B gene variants by gene cloning

Abstract

Native polyacrylamide gel electrophoresis showed that two types of lactate dehydrogenase (LDH) existed in yaks. Based on the electrophoresis characteristics of LDH isoenzymes, yak LDH variants were speculated to be the gene mutation on H subunit encoded by B gene. According to the mobility in electrophoresis, the fast-band LDH type was named LDH-Hf and the slow-band LDH type LDH-Hs. In order to reveal the gene alteration in yak LDH variants, total RNA was extracted from heart tissues of yaks with different LDH variants, and cDNAs of the two variants were reverse transcripted. Two variants of B genes were cloned by RT-PCR. Sequence analysis revealed that four nucleotides differed between LDH-Bf and LDH-Bs, which resulted in two amino acids alteration. By Deepview software analysis of the conformation of yak LDH1 variants and H subunit, these four nucleotides altered two amino acids that generated new hydrogen bonds to change the hydrogen bonds network, and further caused subtle conformational changes between the two LDH variants.

Cloning and Polymorphisms of Yak Lactate Dehydrogenase b Gene

“…Based on the tetramer combination of LDH isozymes, we previously proposed that the occurrence of genetic polymorphisms of H subunit of LDH might give rise to 5 to 2 isozyme forms for LDH1 to LDH4, respectively [6]. In this study, we observed clearly the existence of multiple bands of LDH1 to LDH3 isozymes (Figure 1, lane 7).…”

“…We have previously identified two phenotypes of LDH1 in Maiwa yaks (a yak breed in China) by gene cloning [6], and purified three phenotypes of LDH1 in Jiulong yaks [9]. In this study we obtained three ldhb cDNA sequences, encoding H subunits, of the three LDH1 phenotypes of Jiulong yaks.…”

“…The ldhb gene, or LDH1 polymorphism, has been revealed in several yak breeds by isozyme electrophoresis or gene cloning [5,6], but has not been observed in other cattle species. Whether there is a relationship between yak ldhb polymorphism and hypoxia adaptation is unclear.…”

High-Altitude Adaptation of Yak Based on Genetic Variants and Activity of Lactate Dehydrogenase-1

“…As LDH subunits assemble to form tetramers, theoretically five forms of LDH1 can exist in heterogeneous yak individuals. Likewise, the proposed number of heterogeneous forms of LDH2 is four, LDH3 is three, LDH4 is two, and LDH5 is one (Zheng et al 2008). We did observe multiple bands for LDH1 to LDH3 in this study (Fig.…”

“…These data will assist in the evaluation of the effect of yak LDH1 variants on tissue metabolism. We have previously identified two variants of LDH1 in Maiwa yak (a yak breed in China) by gene cloning (Zheng et al 2008). In this experiment we revealed three LDH1 variants in Jiulong yak by PAGE.…”