Sequencing of total RNA by NGS - Library preparation
The term RNA-Seq or RNA-Seq refers to a next-generation sequencing approach (NGS) that provides a snapshot of the entire transcriptome or messenger RNA (mRNA) profile at a given point in time.
Whole transcriptome analysis aims at capturing coding and non-coding RNA and quantifying the heterogeneity of gene expression in cells, tissues, organs and even the entire body.
The sequencing of the whole transcriptome therefore provides the most complete view possible. It is the method that allows the sequencing of all transcripts of coding and non-coding RNA. In other words, the messenger RNAs that code for proteins but also all other micro RNAs, small interfering RNAs, extracellular RNAs.
The other advantage of whole genome sequencing is that the extraction and purification of the total RNA is easier and cheaper than messenger RNA for example. However, it is necessary to remove the ribosomal RNA that is present in too large quantities and that could interfere with other types of RNA. This is called ribosomal RNA depletion.