Estimation of microRNA (miRNA) enrichment by mapping the sequencing data to the reference.

The list of reference sequences includes hairpin miRNA transcripts, matrix RNAs (mRNAs), ribosomal RNAs (rRNAs), “filtering” RNAs (transfer RNAs, repetitive genome elements, SOLiD™ adapter sequences). Mapping was performed by Bioscope v.1.3 with a seed length of 19, allowing two mismatches. cDNA libraries were constructed on the basis of short RNA fractions: L1 – RNA fraction from the tumour tissue of mice with LLC treated with saline buffer (RNASTc); L2 – RNA fraction from the tumour tissue of mice with LLC treated with RNase A (RNASTR); L3 – RNA fraction from the blood serum of mice with LLC treated with saline buffer (RNASSc); L4 – RNA fraction from the blood serum of mice with LLC treated with RNase A (RNASSR). *- number of reads (percentage of total number mapped on the group of RNAs).

本参考序列列表涵盖发卡型microRNA（miRNA）转录本、信使RNA（mRNA）、核糖体RNA（rRNA）以及“过滤”类RNA（转运RNA（tRNA）、重复基因组元件、SOLiD™接头序列）。序列比对通过Bioscope v.1.3软件完成，设置种子长度为19，允许2个错配。本研究基于短RNA组分构建cDNA文库，具体分组如下：L1——取自经生理盐水缓冲液处理的LLC小鼠肿瘤组织的RNA组分（RNASTc）；L2——取自经核糖核酸酶A处理的LLC小鼠肿瘤组织的RNA组分（RNASTR）；L3——取自经生理盐水缓冲液处理的LLC小鼠血清的RNA组分（RNASSc）；L4——取自经核糖核酸酶A处理的LLC小鼠血清的RNA组分（RNASSR）。*——测序读段（reads）数量（占比对至该组RNA的总读段数的百分比）。