Ontogenetic Expression of <i>Lpin2</i> and <i>Lpin3</i> Genes and Their Associations with Traits in Two Breeds of Chinese Fat-tailed Sheep

Abstract

Lipins play dual function in lipid metabolism by serving as phosphatidate phosphatase and transcriptional co-regulators of gene expression. Mammalian lipin proteins consist of lipin1, lipin2, and lipin3 and are encoded by their respective genes Lpin1, Lpin2, and Lpin3. To date, most studies are concerned with Lpin1, only a few have addressed Lpin2 and Lpin3. Ontogenetic expression of Lpin2 and Lpin3 and their associations with traits would help to explore their molecular and physiological functions in sheep. In this study, 48 animals with an equal number of males and females each for both breeds of fat-tailed sheep such as Guangling Large Tailed (GLT) and Small Tailed Han (STH) were chosen to evaluate the ontogenetic expression of Lpin2 and Lpin3 from eight different tissues and months of age by quantitative real-time polymerase chain reaction (PCR). Associations between gene expression and slaughter and tail traits were also analyzed. The results showed that Lpin2 mRNA was highly expressed in perirenal and tail fats, and was also substantially expressed in liver, kidney, reproductive organs (testis and ovary), with the lowest levels in small intestine and femoral biceps. Lpin3 mRNA was prominently expressed in liver and small intestine, and was also expressed at high levels in kidney, perirenal and tail fats as well as reproductive organs (testis and ovary), with the lowest level in femoral biceps. Global expression of Lpin2 and Lpin3 in GLT both were significantly higher than those in STH. Spatiotemporal expression showed that the highest levels of Lpin2 expression occurred at 10 months of age in two breeds of sheep, with the lowest expression at 2 months of age in STH and at 8 months of age in GLT. The greatest levels of Lpin3 expression occurred at 4 months of age in STH and at 10 months of age in GLT, with the lowest expression at 12 months of age in STH and at 8 months of age in GLT. Breed and age significantly influenced the tissue expression patterns of Lpin2 and Lpin3, respectively, and sex significantly influenced the spatiotemporal expression patterns of Lpin3. Meanwhile, Lpin2 and Lpin3 mRNA expression both showed significant correlations with slaughter and tail traits, and the associations appear to be related with the ontogenetic expression as well as the potential functions of lipin2 and lipin3 in sheep.

Regulatory Roles of SREBF1 and SREBF2 in Lipid Metabolism and Deposition in Two Chinese Representative Fat-Tailed Sheep Breeds

“…Lipid metabolism and deposition is composed of many enzymatic reactions and are often regulated by many molecules [7,25]. Roles of Lpin2/3, angiopoietin-like protein 4, miR-124-3p, and other genes and non-coding RNAs in the regulation of fat deposition from two fat-tailed sheep breeds had been discussed in our previous studies [26][27][28]. Another study by Moradi et al reported that there is a genetic basis for the phenotypic differences between fat-tailed and thin-tailed sheep [29].…”

Transcriptome analysis of adipose tissues from two fat-tailed sheep breeds reveals key genes involved in fat deposition

“…Crossing of sheep breeds with different patterns of fat deposition is one of the agronomical strategies for improving the meat quality. Previous studies have investigated the differences in gene expression patterns or molecular genetic mechanisms between characteristically different sheep breeds [ 3 , 5 , 6 , 26 – 28 ]. To investigate the genetic profiles of fat tissues and to understand the differences in the genetic mechanisms determining fat deposition between distinct breeds, we characterized the transcriptome of PEF, SUF, and TAF from GLT and STH sheep breeds.…”

“…The GLT breed is characterized by large tails and good meat quality but shows low fecundity whereas the STH breed typically has small tails and higher fecundity [ 3 ]. The difference in the content of tail fat between these two breeds has stimulated extensive interest in characterizing the expression of key genes associated with fat deposition, namely UCP-1 , ANGPTL4 , Lpin2 , and Lpin3 [ 3 – 5 ]. However, the fat deposition trait is a complex quantitative trait that is controlled by multiple genes.…”

Expression Patterns of SREBF1 and SREBF2 in Liver and Adipose Tissues of Two Fat-Tailed Sheep Breeds

“…9,30 In our previous studies, the roles of Lpin2/3, angiopoietin-like protein 4, miR-124-3p, and other genes and non-coding RNAs in the regulation of fat deposition from two fat-tailed sheep breeds had been discussed. [31][32][33][34] Therefore, this study mainly focuses on the crucial role of sterol regulatory element binding proteins (SREBPs) in fat-tailed sheep base on the dynamical changes of serum lipid metabolism indicators. SREBPs including SREBP-1a, SREBP-1c and SREBP2 are mainly responsible for regulating cellular lipogenesis and lipid homeostasis.…”