Navet S, Buresi A, Baratte S, Andouche A, Bonnaud-Ponticelli L, Bassaglia Y (2017) The Pax gene family: Highlights from cephalopods. PLoS ONE 12(3): e0172719. doi:10.1371/journal.pone.0172719
Pax genes play important roles in Metazoan development. Their evolution has been extensively studied but Lophotrochozoa are usually omitted. Yann Bassaglia and his colleagues of Team 2 have addressed the question of Pax paralog diversity in Lophotrochozoa by a thorough review of available databases. The existence of six Pax families was confirmed but contrary to the pattern reported in chordates, the Pax2/5/8 family is different in Lophotrochozoa. In order to study their role during the development of our model species, Sepia officinalis, and by a comparative approach with other Lophotrochozoans, the expression patterns of the three main pax classes (pax2/5/8, pax3/7, pax4/6) have been established. Surprisingly, Pax roles taken as ancestral and common in metazoans are modified in S. officinalis, most likely due to either the morphological specificities of cephalopods or to their direct development. This study underlines the diversity and functional plasticity of Pax genes and illustrates the difficulty of using probable gene homology as strict indicator of homology between biological structures.
Contact : Yann Bassaglia, assistant professor UPEC, yann.bassaglia@mnhn.fr