Regulatory roles of adiponectin receptor 1 and 2 in sheep preadipocytes during adipocyte differentiation

Presence, Tissue Localization, and Gene Expression of the Adiponectin Receptor 1 in Testis and Accessory Glands of Male Rams during the Non-Breeding Season

Adiponectin (ADIPOQ) is a member adipocytokines, and its actions are supported by two receptors, ADIPOQ receptor 1 and -2, respectively (ADIPOR1 and -R2). Our study was performed to evaluate the ADIPOR1 presence and location and its gene expression in reproductive tissues of the male ram, during its non-breading season. The different portions of the male ram reproductive system (testis, epididymis, seminal vesicle, ampoule vas deferens, bulb-urethral gland) were collected in a slaughterhouse. Immunohistochemistry showed ADIPOR1 positive signals in the cytoplasm of all the glandular epithelial cells, with a location near the nucleus; in the testes, the positive reaction was evidenced in the cytoplasm in the basal portion of the germinal epithelial cells. The immune reaction intensity was highest (p < 0.001) in the prostate and seminal vesicles glands than that of other parts of the ram reproductive tract. RT-qPCR detected the ADIPOR1 transcript in the testes, epididymis, vas deferens, bulbourethral glands, seminal vesicles, and prostate; the expression levels were high (p < 0.01) in the prostate and low (p < 0.01) in the testis, epididymis, and bulbourethral glands. The present results evidenced the possible ADIPOQ/ADIPOR1 system's role in regulating the testicular activity of male rams during the non-breading season.

Genetics of the phenotypic evolution in sheep: a molecular look at diversity-driving genes

BACKGROUND

After domestication, the evolution of phenotypically-varied sheep breeds has generated rich biodiversity. This wide phenotypic variation arises as a result of hidden genomic changes that range from a single nucleotide to several thousands of nucleotides. Thus, it is of interest and significance to reveal and understand the genomic changes underlying the phenotypic variation of sheep breeds in order to drive selection towards economically important traits.

REVIEW

Various traits contribute to the emergence of variation in sheep phenotypic characteristics, including coat color, horns, tail, wool, ears, udder, vertebrae, among others. The genes that determine most of these phenotypic traits have been investigated, which has generated knowledge regarding the genetic determinism of several agriculturally-relevant traits in sheep. In this review, we discuss the genomic knowledge that has emerged in the past few decades regarding the phenotypic traits in sheep, and our ultimate aim is to encourage its practical application in sheep breeding. In addition, in order to expand the current understanding of the sheep genome, we shed light on research gaps that require further investigation.

CONCLUSIONS

Although significant research efforts have been conducted in the past few decades, several aspects of the sheep genome remain unexplored. For the full utilization of the current knowledge of the sheep genome, a wide practical application is still required in order to boost sheep productive performance and contribute to the generation of improved sheep breeds. The accumulated knowledge on the sheep genome will help advance and strengthen sheep breeding programs to face future challenges in the sector, such as climate change, global human population growth, and the increasing demand for products of animal origin.

ADIPOR1 regulates genes involved in milk fat metabolism in goat mammary epithelial cells

BACKGROUND

Fat metabolism is a complex process regulated by a number of factors. Adiponectin receptor 1 (ADIPOR1) gene takes active part in lipid metabolism. Although, there have been some researches indicating that ADIPOR1 could influence the milk fat metabolism through targeting some factors, little is known about the effect of ADIPOR1 on goat milk fat metabolism. To investigate the regulatory role of ADIPOR1 on milk fat metabolism in GMECs, we analysed overexpression in the presence and absence of AdipoRon (50 μM) and examined knockdown using siRNA. Using RT-qPCR, we assessed ADIPOR1 mRNA expressions among different lactation stages in goat mammary gland and the expression of six genes that regulate milk fat metabolism in GMECs.

RESULTS

ADIPOR1 mRNA expression level was higher during the various lactation stages, except dry-off period. Knockdown and overexpression results revealed a significant decrease and increase in mRNA expression of ADIPOR1 and genes considered: SREBF1, ACACA, FASN, SCD, ATGL, and HSL, respectively. Treatment of GMECs with AdipoRon 50 μM resulted in a significant (p < 0.05) increase in the mRNA expression of all measured genes, except SREBF1.

CONCLUSION

Overall, ADIPOR1 plays a central role in regulating the transcription of several genes involved in milk fat metabolism.