Protein function evolution multidomain proteins

Oligomeric states of similarly folded subunits can be very disparate in architecture through evolution and have implications in terms of functions as it has been well exemplified with the hemoglobin family (Royer et al. 2005). The gain of modularity expected by switching from a single domain to multidomains proteins and then to supramolecular assemblies, the fact that components of stable complexes are more conserved than transient ones as well as the fact that essential proteins tend to be subunit of complexes have been discussed from the point of view of evolution (Pereira-Leal et al. 2006 Bomberg-Bauer et al. 2005). 

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