To understand the function and mechanisms of postranslational modification is crucial to understand protein function. Modifications by the Small Ubiquitin-like Modifier (SUMO) to target proteins are proven to be important in critical developmental processes, such as cell division, DNA repair, etc. A recent manuscript by the groups of David Martín at the Institute of Evolutionary Biology (CSIC–UPF) and Rosa Barrio at CIC bioGUNE (Derio), and in collaboration with researchers from Inbiomed (Donostia-San Sebastián, Gipuzkoa), demonstrates the conservation of the role of SUMOylation in the metamorphosis across insect species, particularly in the control of cell proliferation and ecdysteoid synthesis and signalling.

Moreover, phylogenetic analysis carried out in this work show that the ancestral SUMO gene was duplicated early in Metazoan evolution giving rise to SUMO1 and SUMO2/3 families. Interestingly, the work shows that SUMO1 or SUMO2/3 genes were lost in different animal groups during evolution, implying a functional diversification of the SUMO paralogues. SUMO moieties can be in turn SUMOylated, forming polySUMO chains that have functional significance. This study shows that insect paralogues do not form polySUMO chains in vitro. Taken together, the findings reported in the manuscript contribute to the understanding of the functional consequences of polySUMO chain formation and of the evolution of SUMO genes. The results were published in the journal Molecular Biology and Evolution (Oxford Journals).

Reference Article: Ureña E, Pirone L, Chafino S, Pérez C, Sutherland JD, Lang V, Rodriguez MS, Lopitz-Otsoa F, Blanco FJ, Barrio R*, Martín D*. Evolution of SUMO function and chain formation in insects. Mol Biol Evol. 2015 Nov 4. pii: msv242. doi: 10.1093/molbev/msv242