A complex network of molecular events triggered upon environmental cues which decide the fate of gene expression: a review

Abstract

Gene expression in eukaryotes depends on a web of events which are inter-related and tightly regulated. These key events can be broadly classified into post-transcriptional and post-translational processes. In general the post-transcriptional events include pre-mRNA processing (capping, splicing, polyadenylation), RNA stability, and translation as well as chromatin modifications through regulatory RNAs (miRNA, siRNAs and long non-coding RNAs). Protein phosphorylation, ubiquitination and sumoylation are a few post-translational events. These events are constitutitive as well as provoked by specific exogenous and/or endogenous stimuli. In case of the plant system, the molecular mechanisms responsible for regulating the gene expression is diverse and yet to be fully revealed. A lot of exogenous signals including abiotic stresses do decide the fate of a gene thus making the system more complex than the others. The molecular response of plants to abiotic stresses is more often considered as a complex process mainly based on strict modulation of post-transcriptional and post-translational events of stress-related genes. The network of post-transcriptional and post-translational events do ensure temporal and spatial suitable patterns of downstream stress-related gene expression. The current review mainly focus on a variety of molecular events which play a pivotal role in fine tuning the gene expression in eukaryotes.