Diagram of USLP method on screening miRs.

<p>Light blue lines indicate total RNA. Arrowheads indicate directions of polymerization. 8 random sequences at the 3′ end of stem-loop primer (red) can bind to all mature miRs. In the reaction, mature miR was reversely transcribed into cDNA under the reaction conditions of RT; then, miR was screened and quantified by fluorescence quantitative PCR using miR specific forward primer and universal reverse primer. The forward PCR primer adds additional length with nucleotides that optimize its melting temperature (Tm) and enhance assay specificity. A universal reverse primer that is complementary to a sequence within the RT stem-loop primer.