Ontogenetic Expression of Lpin2 and Lpin3 Genes and Their Associations with Traits in Two Breeds of Chinese Fat-tailed Sheep.

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.

[Determination of trace element contents in Urtica laetevirens Maxim. reaped in different months by ICP-MS].

The contents of twenty kinds of trace elements, Al, Ba, Ca, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, S and Zn, were determined by ICP-MS with microwave digestion in Urtica laetevirens Maxim. The recovery (n=7) is 95.4%-101.2%, and the RSD (n=7) is 1.2%-5.3%. The contents of K, P, S, Ca and Na in the samples were abundant while Fe, Mg, Mn and Zn were less abundant. The contents of Al, Cr and Pb which were harmful to human were kept at low level. The contents of trace elements in Urtica laetevirens Maxim. also showed obvious seasonal dynamics. This result provides some theoretical basis for the study of internal relations between trace elements in Urtica laetevirens Maxim. and its efficacy. It's also useful for better development and utilization of the resource.