The general steps to prepare a complementary DNA (cDNA) library for sequencing are described below, but often vary between platforms.
RNA Isolation: RNA is isolated from tissue and mixed with deoxyribonuclease (DNase). DNase reduces the amount of genomic DNA. The amount of RNA degradation is checked with gel and capillary electrophoresis and is used to assign an RNA integrity numberto the sample.Different RNA sequencing methods: Whole transcriptome sequencing:. The whole transcriptome of a cell or tissue- all RNAs (mRNA, tRNA, rRNA, sncRNA,... Target RNA sequencing:. A gene-specific, cluster of gene-specific, a pathway-specific or disease-related transcriptomes