The Expression of ERK1/2 in Female Yak (Bos grunniens) Reproductive Organs

Abstract

The main reproductive organs undergo different histological appearances and physiological processes under different reproductive statuses. The variation of these organs depends on a delicate regulation of cell proliferation, differentiation, and apoptosis. Extracellular signal-regulated kinases1/2 (ERK1/2) are members of the mitogen-activated protein kinase (MAPK) super family. They have important roles in regulating various biological processes of different cells, tissues, and organ types. Activated ERK1/2 generally promotes cell survival, but under certain conditions, ERK1/2 also have the function of inducing apoptosis. It is widely believed that ERK1/2 play a significant role in regulating the reproductive processes of mammals. The goal of our research is to investigate the expression and distribution of ERK1/2 in the yak’s main reproductive organs during different stages. In the present study, samples of the ovary, oviduct, and uterus of 15 adult female yak were collected and used in the experiment. The ERK1/2 proteins, localization, and quantitative expression of their mRNA were investigated using immunohistochemistry (IHC), western blot (WB) and relative quantitative real-time polymerase chain reaction (RT-PCR). The results indicated that ERK1/2 proteins and their mRNA were highly expressed in the ovary of the luteal phase and gestation period, in the oviduct of the luteal phase, and in the uterus of the luteal phase and gestation period. Immunohistochemical analysis revealed a strong distribution of ERK1/2 proteins in follicular granulosa cells, granular luteal cells, villous epithelial cells of the oviduct, endometrial glandular epithelium, and luminal epithelium. These results demonstrated that the expression of ERK1 and ERK2 proteins and their mRNA in the yak’s ovary, oviduct, and uterus varies with the stage of the reproductive cycle. The variation character of ERK1 and ERK 2 expression in the yak’s main reproductive organs during different stages implies that they play an important role in regulating the reproductive function under different physiological statuses.

Identification of key genes and biological pathways in different parts of yak oviduct based on transcriptome analysis

“…The oviduct is an important site for fertilization in yaks and previous studies focused on its morphology ( 18 ), POxia-inducible factor-1 alpha ( 19 ), ERK1/2 ( 20 ), estrogen receptor genes ( 21 ), follicle-stimulating hormone receptor (FSHR) gene ( 22 ), DNA damage induced transcript 3 ( 23 ), and apoptosis-related genes in the yak oviduct ( 24 ). There are currently no transcriptomic studies on the different parts of the yak oviduct, and there is a lack of research on the fertilization mechanism from the perspective of mRNA.…”

Label‐free proteomic analysis reveals an estrous cycle transition between the follicular phase and the luteal phase in yak ovary

“…Luteal phase group: only one luteal body ≥10.0 mm, no follicle >8.0 mm. The corpus luteum of both ovaries is small, and the uterine horns of both ovaries are symmetrical and undilated (Fan et al, 2020). The ovaries were quickly removed, washed with PBS three times, and then put into liquid nitrogen for later use.…”

Oviduct Epithelial Cells Constitute Distinct Lineages from the Ampulla to the Isthmus Related to High-Altitude Adaptation in Yak (Bos grunniens)

“…The mechanisms of these high rates of oxidation will help us understand the regulation of lipid metabolism. Other than that, the expression of apoptosisrelated genes[6], ERK1/2 [7], DDIT3[8], HIF-1a [9], and FSHR [10] in reproductive organs of female yaks has been studied. Currently, studies on high altitude adaptation of hearts, lungs, epididymides, muscle, spleens and other organs in yaks have been carried out, but there is still a lack of studies on the oviduct to provide the evidence about the relation between low pregnancy rate and high-altitude adaptation in yaks.…”