Small RNA biology is systems biology

Daniel Jost, Andrzej Nowojewski, Erel Levine
2011 BMB Reports  
Fig. 1. Outline of three srRNA pathways in animals (miRNA and siRNA) and bacteria (Hfq-dependent sRNAs). During the last decade small regulatory RNA (srRNA) emerged as central players in the regulation of gene expression in all kingdoms of life. Multiple pathways for srRNA biogenesis and diverse mechanisms of gene regulation may indicate that srRNA regulation evolved independently multiple times. However, small RNA pathways share numerous properties, including the ability of a single srRNA to
more » ... gulate multiple targets. Some of the mechanisms of gene regulation by srRNAs have significant effect on the abundance of free srRNAs that are ready to interact with new targets. This results in indirect interactions among seemingly unrelated genes, as well as in a crosstalk between different srRNA pathways. Here we briefly review and compare the major srRNA pathways, and argue that the impact of srRNA is always at the system level. We demonstrate how a simple mathematical model can ease the discussion of governing principles. To demonstrate these points we review a few examples from bacteria and animals. (BMB reports 2011; 44(1): 11-21) Small RNAs in Animals Multiple srRNA pathways exist in animals, including the well studied microRNAs (miRNAs), endogenous small-interfering RNAs (siRNAs) in the RNAi pathway, and Piwi-interacting RNAs (piRNAs) (Fig. 1) . MiRNAs have been shown to play significant roles in all fields of biology, including development (reviewed in 12, 13), stem cell differentiation (14) , germline maintenance (15, 16), cancer biology (17) and stress response (18). piRNAs have been implicated in maintenance of genomic integrity and suppression of transposon activity (19). The role endogenous siRNAs is even more diverse and less Invited Mini Review Small RNA biology is systems biology Daniel Jost, et al. Small RNA biology is systems biology Daniel Jost, et al. 13 BMB reports
doi:10.5483/bmbrep.2011.44.1.11 pmid:21266101 fatcat:ymlrmih2wnblpodmq2y5tlscqe