Abstract:

Abstract  Objective: Solexa Sequencing was used to screen for kidney-specific microRNAs. The target genes of the identified miRNAs were analysed by bioinformatics to predict the biological functions of the miRNAs.  Methodology: To screen for the miRNAs specifically expressed in kidney, leven tissues or organs from 8 weeks C57 / B6 male mice were collected. Total RNA was extracted, followed by small RNA isolation. Solexa sequencing was performed to profile the small RNA samples. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to validate the results from the sequencing. Bioinformatic analysis was performed to predict the target genes of the kidney specific miRNAs. The predicted target genes were subject to gene ontology (GO) and KEGG pathway analyses for function prediction. Results: Solexa sequencing results showed that miR-196a and miR-196b were the kidney specific miRNAs in normal mice. The distribution of miR-196a and miR-196b in 11 tissues or organs of mice were validated by q-PCR, and the results were consistent with those from sequencing. The number of overlapping predicted target genes by TargetScan6.2 and PicTar was 74. GO analysis showed that the genes involved in the regulation of platelet-derived growth factor binding, transcriptional activity and extracellular matrix structural constituent were enriched in the list of the 74 genes. The genes associated with several biological processes, including metabolic process and developmental process, were also enriched among the 74 genes (p <0.01). The pathway analysis showed that the genes involved in GnRH signaling, ECM-receptor interaction, and glioma and prostate cancer, were significantly enriched in the 74 genes (p <0.05). Conclusion: miR-196a/b specifically expressed in the kidney, and their functions are predicted to be closely related with cell metabolism, growth and development. Thus, our study may help understand the mechanism underlying kidney disease. Further studies are required to understand the role of miR-196a/b in the physiology and pathology of kidney.
  

Key words:  kidney, Solexa sequencing, miR-196a, miR-196b