1. MiR-19b-3p Regulates MAPK1 Expression in Embryonic Fibroblasts from the Great Tit (Parus Major) Under Hypoxic Conditions
- Author
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Gang Song, Jing Wang, Huishan Zhang, Fumin Lei, Xiaohua Lei, Yanhua Qu, Haitao Wang, Xiumin Chen, and Yalin Cheng
- Subjects
0301 basic medicine ,endocrine system ,Candidate gene ,Embryo, Nonmammalian ,Physiology ,miR-19b-3p ,Apoptosis ,Biology ,lcsh:Physiology ,Cell Line ,Avian Proteins ,MAPK1 ,Hypoxic Adaptation ,lcsh:Biochemistry ,03 medical and health sciences ,0302 clinical medicine ,RNA interference ,microRNA ,Animals ,Embryonic Fibroblasts ,Gene Regulatory Networks ,lcsh:QD415-436 ,Passeriformes ,RNA, Small Interfering ,3' Untranslated Regions ,Gene ,In Situ Hybridization, Fluorescence ,Cell Proliferation ,Mitogen-Activated Protein Kinase 1 ,Parus ,Gene knockdown ,Base Sequence ,lcsh:QP1-981 ,Sequence Analysis, RNA ,Three prime untranslated region ,Antagomirs ,Cell Cycle Checkpoints ,Fibroblasts ,biology.organism_classification ,Cell Hypoxia ,Cell biology ,MicroRNAs ,030104 developmental biology ,030220 oncology & carcinogenesis ,RNA Interference ,Sequence Alignment - Abstract
Background/Aims: Genomic adaptations to high altitudes have been well studied in the last several years; however, the roles of microRNAs (miRNAs), which are essential modulators of a variety of genes and key cellular processes, have rarely been explored. Here, we explored the interactions between miRNAs and their target genes as an adaptation to high altitude in an avian species, the great tit ( Parus major ), which is widely distributed across the Eurasian continent at altitudes between 4500 m and sea level. Because the MAPK signaling pathway plays a crucial role in the hypoxia response in the great tit, we chose MAPK1 as a target candidate gene. Methods: We established a great tit embryonic fibroblast line and subsequently studied the relationship between miRNA-19b-3p and MAPK1 in normoxia and hypoxia groups. Meanwhile, the great tit embryonic fibroblasts (GEFs) were treated or transfected with miR-19b-3p mimics, inhibitors, or si-MAPK1, and their proliferation was subsequently assessed using the MTT assay. The expression of the miRNAs and MAPK1 was measured by real-time PCR and Western blotting. Results: We identified 14 miRNAs in the cardiac tissues of great tits that are related to hypoxia adaptation. MAPK1 binds only to miR-19b-3p of the 14 miRNAs predicted by both TargetScan and miRanda software. Specifically, we validated the computational prediction of miR-19b-3p binding to the 3’UTR of MAPK1 using a luciferase reporter assay. Our results show that miR-19b-3p promotes GEFs proliferation and up-regulates MAPK1 expression. Moreover, miR-19b-3p mimics and MAPK1 knockdown induce GEFs apoptosis and regulate the cell cycle under hypoxic conditions. Conclusions: Our study is the first to describe an important miRNA-mediated regulatory mechanism of high altitude adaptation in a non-model wild songbird and highlights the importance of studies on miRNA-mediated mechanisms of hypoxic adaptations in other animals.
- Published
- 2018