MicroRNA-17 post-transcriptionally regulates polycystic kidney disease-2 gene and promotes cell proliferation

Abstract

To identify the possible microRNAs (miRNAs) which target the polycystic kidney disease-2 gene (PKD2), and clarify effects of the miRNAs on PKD2. We preliminarily used bioinformatics to analyze 3'UTR (3'untranslated regions) of PKD1 and PKD2 in order to predict the potential microRNAs targeted on them. Subsequently, the stable cell lines with overexpression of microRNA-17 (miR-17) were screened, and luciferase assay combined with the mutation 3'UTR of PKD2 were performed to verify PKD2 is the target of miR-17. Moreover, RT-PCR and Western Blotting were used to determine the post-transcriptionally regulation of PKD2 by miR-17. Finally, MTT cell assays allied with PKD2 rescued strategy were employed to evaluate cell proliferation effects. Our study firstly found that the 3'UTR of PKD2 was more conservation than that of PKD1, and microRNA-17 directly targets the 3'UTR of PKD2 and post-transcriptionally repress the expression of PKD2. Moreover, our findings also demonstrated that overexpression of miR-17 may promote cell proliferation via post-transcriptionally repression of PKD2 in HEK 293T. This suggested that microRNA might be a novel mechanism for cystogenesis as well as a potential therapeutic target for the cell proliferation of autosomal dominant polycystic kidney disease (ADPKD).

MicroRNA-497 Suppresses Proliferation and Induces Apoptosis in Prostate Cancer Cells

“…miRNAs, a class small regulatory RNA molecules that repress gene expression of their mRNA targets in a sequence specific manner, have been identified as key regulators in a wide variety of oncogenic processes, such as cell proliferation, angiogenesis, cellular differentiation, invasion and metastasis, and can function as either tumor suppressors or oncogenes (Kefas et al, 2008;Sun et al, 2010;Zhang et al, 2010).…”

miR-17∼92 miRNA cluster promotes kidney cyst growth in polycystic kidney disease

“…S7). miR-17 has been shown to posttranscriptionally regulate Pkd1 and Pkd2 in cultured cells (15,22,23). However, whether miR-17 inhibits Pkd1 or Pkd2 expression in vivo is not known.…”

Far Upstream Element-Binding Protein 1 Binds the 3′ Untranslated Region of PKD2 and Suppresses Its Translation

“…Indeed, a short upstream open reading frame in PKD2 mRNA 59UTR is implicated in the translational upregulation of PKD2 by cellular stresses 18 , and microRNA-17 post-transcriptionally downregulates PKD2 expression by binding to its mRNA 39UTR thereby promoting cell proliferation. 26 Furthermore, it was reported that the RNA-binding protein bicaudal C upregulates PKD2 expression by antagonizing the repressive activity of miR-17 through binding competitively to the same site on the PKD2 mRNA 39UTR. 7 Of note, the 3FI and 3FS identified in this study do not overlap with the miR-17 binding site.…”

“…For this we made BI16 constructs with nt 118-145 deletion from 39UTR and nt 1-1044, and found that the deletion has minimal or no effect on luciferase activity ( Figure 1D), suggesting that native miR-17 and Bicc1 do not play a significant role under these conditions, although overexpressed miR-17 is reported to exhibit a modest inhibitory effect. 26 Next we further divided nt 1-1044 and nt 1025-2087 into overlapping fragments and identified that nt 1-1044 and nt 691-1044 mediate inhibition of luciferase, whereas nt 1025-1129 mediates stimulation ( Figure 2). Of note, the nt 691-1044 fragment had slightly less inhibitory effect on luciferase expression than nt 1-1044 (Figure 2A), although the reason for this is unclear.…”