MOLECULAR CARACTERIZATION AND EXPRESION PATTERNS OF C2H2-TYPE ZINC FINGER TRANSCRIPTION FACTORS INVOLVED IN THE DEVELOPMENT OF GRASS INFLORESCENCE

BELLINO C.D.; REINHEIMER R.

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017

The grass family includes species among which are outstandingcereals that constitute a very important part of human intake. Thefinal form of a grass inflorescence is the result of a balance betweenthe ability of the axillary meristems to form branches or terminatein spikelets. The Cys2-His2-type (C2H2) zinc finger transcriptionfactors seem to play a central role at this stage of development.The aim of this work is to explore the molecular and functional divergenceof these proteins in grasses. By comparison of C2H2 zincfinger peptide sequences available on databases and others generatedin our laboratory, we observed a little conservation of the sequencestowards the C-terminal. From this sequence alignment wereconstructed the molecular evolution of the genes coding for C2H2zinc finger proteins. As a result, we identified two successive duplicationsaround the origin of the grasses that generated at least threeexclusive lineages of grass C2H2 zinc finger proteins, for which littleinformation on their biological role is available. To begin with theircharacterization, we investigated the expression preference of thecoding genes throughout the whole body of the plant (root, stem,leaf and inflorescence) of the model species Setaria viridis. In particular,such genes are preferentially expressed in inflorescence withdeveloping branches. The expression decays at late stages of inflorescencedevelopment (during initiation and differentiation of floralorgans). So far, our results show that the genes coding for the C2H2zinc finger proteins have been diversified in grasses and they mayplay an important role in the evolution of the branching system ofgrass inflorescences.