MicroRNA-370-5p inhibits pigmentation and cell proliferation by downregulating mitogen-activated protein kinase kinase kinase 8 expression in sheep melanocytes  

作　　者：JI Kai-yuan WEN Ru-jun WANG Zheng-zhou TIAN Qian-qian ZHANG Wei ZHANG Yun-hai 

机构地区：[1]Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control,College of Animal Science and Technology,Anhui Agricultural University,Hefei 230036,P.R.China [2]Anhui Province Key Laboratory of Local Livestock and Poultry Genetic Resources Conservation and Bio-Breeding,College of Animal Science and Technology,Anhui Agricultural University,Hefei 230036,P.R.China [3]Linquan Comprehensive Experimental Station,Anhui Agricultural University,Linquan 236400,P.R.China

出　　处：《Journal of Integrative Agriculture》2023年第4期1131-1141,共11页农业科学学报（英文版）

基　　金：funded by the Natural Science Foundation of Anhui Province,China(2008085QC158);the University Natural Science Research Project of Anhui Province(KJ2019A0165)。

摘　　要：In mammals,microRNAs(miRNAs)play key roles in multiple biological processes by regulating the expression of target genes.Studies have found that the levels of miR-370-5p expression differ significantly in the skins of sheep with different hair colors;however,its function remains unclear.In this study,we investigated the roles of miR-370-5p in sheep melanocytes and found that the overexpression of miR-370-5p significantly inhibited cell proliferation(P<0.01),tyrosinase activity(P=0.001)and significantly reduced(P<0.001)melanin production.Functional prediction revealed that the 3′-untranslated region(UTR)of MAP3K8 has a putative miR-370-5p binding site,and the interaction between these two molecules was confirmed using luciferase reporter assays.In situ hybridization assays revealed that MAP3K8 is expressed in the cytoplasm of melanocytes.The results of quantitative RT-PCR and Western blotting analyses revealed that overexpression of miR-370-5p in melanocytes significantly inhibits(P<0.01)MAP3K8 expression via direct targeting of its 3′UTR.Inhibition of MAP3K8 expression by siRNA-MAP3K8 transfection induced a significant inhibition(P<0.01)of melanocyte proliferation and significant reduction(P<0.001)in melanin production,which is consistent with our observations for miR-370-5p.Target gene rescue experiments indicated that the expression of MAP3K8 in melanocytes co-transfected with miR-370-5p and MAP3K8-cDNA(containing sites for the targeted binding to miR-370-5p)was significantly rescued(P≤0.001),which subsequently promoted significant increases in cell proliferation(P<0.001)and melanin production(P<0.01).Collectively,these findings indicate that miR-370-5p plays a functional role in inhibiting sheep melanocyte proliferation and melanogenesis by downregulating the expression of MAP3K8.

关 键 词：MICRORNA mitogen-activated protein kinase kinase kinase 8 MELANOGENESIS sheep melanocytes cell proliferation 

分 类 号：S826[农业科学—畜牧学]