Gene-Centered Regulatory Network Mapping - Caenorhabditis Elegans: Molecular Genetics and Development - page 269

Fig. 2 A) The first levels of gene regulation of the 20,000 protein-coding genes are controlled
transcriptionally by 940 TFs that can either activate or repress transcription and post-transcriptionally
by 150 microRNAs that repress mRNA translation and/or stability. B) Cartoon of a gene regulatory
network involving genes, TFs, and microRNAs.
mRNAs, and this is controlled by the action of regulatory transcription factors (TFs)
that can repress or activate gene expression by directly interacting with the genome.
Second, mRNA stability and translation are controlled by small RNAs such as
microRNAs, and by RNA binding proteins that frequently interact with the 3 0 UTR
of their target mRNAs. Third, after translation, proteins can be stabilized or desta-
bilized due to post-translational modifications by, for example, kinases or acety-
lases. Finally, sub-cellular mRNA and protein localization can be subject to control
mechanisms as well.
The delineation of the complex networks that comprehensively describe the
physical and regulatory interactions at each of these levels and between all