Ricerc@Sapienza

From 1993, year of their first observation, up to now, microRNAs (miRNAs) were found to be involved in the regulation of a plethora of processes, from cellular development to proliferation, from survival to apoptosis, thus playing a central role in gene regulation both in health and disease [Bartel-2009,Cesana-2011].
The observation that miRNAs can act as mediators of effective interactions among their common targets (competing for endogenous RNAs or ceRNAs) has brought forward the idea (i.e., the ceRNA hypothesis) that RNAs can regulate each other in extended cross-talk networks. Such an ability being pivotal in post-transcriptional regulation to shape a cell¿s protein repertoire. In fact, by being able to target different RNA species with different kinetics, they can act as the mediators of an effective interaction between the RNAs, such that a change in the level of one RNA can result in an alteration of the levels of another RNA.
Furthermore, the involvement of miRNAs in peculiar motifs of the human post-transcriptional regulatory (PTR) network suggests that they actively perform noise processing in gene expression.
Recent work has characterized the emergent properties of cross-talk and noise processing in small regulatory motifs in silico [Figliuzzi-2013, Bosia-2013]. Small motifs are however embedded in large, cell-scale strongly heterogeneous networks of interactions. Perturbations could propagate across this network and affect RNAs that are topologically distant through chains of miRNA-mediated couplings, creating a collective, long-range mode of regulation characterized by strong and selective cross-talks. A quantitative appraisal of this scenario, of its evolutionary signatures and of its biological consequences is our central goal.

[Bartel. Cell-2009]
[Cesana,Cacchiarelli,Legnini,Santini,Sthandier,Chinappi,Tramontano,Bozzoni. Cell-2011]
[Figliuzzi,Marinari,De Martino. Biophysical Journal-2013]
[Bosia,Pagnani,Zecchina. PloS one-2013]