Non-coding small RNA profiling by high throughput sequencing of bovine primary retinal microvascular endothelial cells

The aim of this study was to identify and quantify microRNAs and other small regulatory RNAs expressed in primary retinal microvascular endothelial cells (RMECs) using deep sequencing. RMECs were isolated, RNA extracted, a small RNA library prepared and deep sequencing performed. A total of 6.8 million reads were mapped to 250 known microRNAs in miRBase (release 16). Several novel microRNAs and multiple new members of the miR-2284/2285 family were detected. Several ~30 nucleotide sno-miRNAs were identified, with the most highly expressed being derived from snoRNA U78. Highly expressed microRNAs previously associated with endothelial cells included miR-126 and miR-378, but the most highly expressed was miR-21, comprising more than one third of all mapped reads. The independence from prior sequence knowledge provided by deep sequencing facilitates analysis of novel microRNAs and other small RNAs. This approach also enables quantitative evaluation of microRNA expression, which has highlighted the predominance of a small number of microRNAs in RMECs. Further characterisation of the functions of the highly expressed microRNAs will provide insights into endothelial biology. Overall design: Single sample of primary cell culture

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Guduric-Fuchs J, O'Connor A, Cullen A, Harwood L, Medina RJ, O'Neill CL, Stitt AW, Curtis TM, Simpson DA