Advances and Challenges in Metatranscriptomic Analysis

New-era genomic tools have proved themselves a big boon in showing a path to get an insight to microbial evolution, taxonomic profiling, active members of a community and the genes involved in many metabolic pathways. Shotgun metagenomics helps in random sequencing of genome of the studied microbiome; however, it does not show the exact number of active genes or the functionally active genomic members. This lacuna calls for the role of metatranscriptomics which studies the differential gene expression and has tremendously participated in the unearthing the multifariousness of active genes, quantification of their expression levels and their response to different environmental and biological conditions. This chapter linchpins the various tools and techniques used in metatranscriptomic analysis of any microbial community. We focus on the major headways in this exponentially proliferating field, comparing the various options used in computational bioinformatic analysis of data and the challenges associated with them.