title: MicroRNA‑21 inhibits SMAD7 expression through a target sequence in the 3' untranslated region and inhibits proliferation of renal tubular epithelial cells.
abstract: MicroRNAs (miRNAs) are a class of small non‑coding single‑stranded RNAs that regulate gene expression at the posttranscriptional level. Since the identification of miRNA, accumulating research has shown their involvement in numerous biological processes, including timing of developmental patterning, embryogenesis, cell differentiation, organogenesis, growth control and pathogenesis of human diseases. It is estimated that >30% human genes may be regulated by miRNA, and that each miRNA can regulate >100 target mRNAs. The widespread and distinct expression pattern of miRNAs in normal and disease states has been extensively investigated in the context of human diseases. Due to the diversity of targets, it is challenging to identify the specific target genes and elucidate the biological function of a certain miRNAs. In the present study, it was confirmed that SMAD7 is a direct target of miR‑21, and overexpression of miR‑21 may inhibit the proliferation of rat renal tubular epithelial cells. These findings confirm the results of previous studies, which have demonstrated that miR‑21 regulates the expression of SMAD7 protein. However, further investigation is required to determine whether miR‑21 is involved in renal development and disease, particularly diabetic nephropathy.
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Lin
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Hua
authors.initials: H
authors.lastname: Gan
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Han
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Experiment Center, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Weixue
authors.initials: W
authors.lastname: Tang
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Xueqin
authors.initials: X
authors.lastname: Tang
authors.affiliation: Department of Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Dequan
authors.initials: D
authors.lastname: Kong
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Wannan Medical College, Wuhu, Anhui 241100, P.R. China.
authors.forename: Jiajun
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Yuxuan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Yanlin
authors.initials: Y
authors.lastname: Zhu
mesh_terms: D020413:3' Untranslated Regions; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D049109:Cell Proliferation; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D005822:Genetic Vectors / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D007684:Kidney Tubules / Q000166:cytology; D016086:Lentivirus / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D016415:Sequence Alignment; D051906:Smad7 Protein / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism
chemical_list: D020413:3' Untranslated Regions; D035683:MicroRNAs; D051906:Smad7 Protein; C546082:mirn21 microRNA, rat