Identification and comparative genomics of OVATE family members from Gramineae uncovers sequence and structural diversity, evolutionary trends, and insights into functional features

Ovate family proteins (OFPs) are plant-specific, transcriptional repressors characterized by an OVATE domain. The OFP family has been analyzed only from a handful and functionally characterized from even fewer species. There is a gap in cataloging the complete compendium of OFP family across Gramineae although the complete genome sequence for several species are now available. In the present study, we identified and cataloged homologs of OFPs across ten Gramineae members to analyze gene and protein structure and properties, evolutionary relationship, expression pattern, and predict interacting partners. A positive correlation was found between genome-size and OFP family size, with Triticum genome harboring the maximum number; most of the Gramineae OFPs are intronless. Comparative analysis revealed variation in gene sizes, physico-chemical properties of proteins, and their structures including motifs. Phylogenetic reconstruction reflected homolog-based clustering. Expression analysis in Oryza revealed spatio-temporal variation with maximum expression in reproductive tissues. Prediction of interactome showed homeobox domain containing proteins as major interacting partners. The study thus form foundation for future functional analysis of role of OFPs in regulating economically important traits.