AUTHOR=Madrigal Yesenia , Alzate Juan F. , Pabón-Mora Natalia 

TITLE=Evolution and Expression Patterns of TCP Genes in Asparagales

JOURNAL=Frontiers in Plant Science

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2017.00009

DOI=10.3389/fpls.2017.00009

ISSN=1664-462X

ABSTRACT=<p><italic>CYCLOIDEA-like</italic> genes are involved in the symmetry gene network, limiting cell proliferation in the dorsal regions of bilateral flowers in core eudicots. <italic>CYC-like</italic> and closely related <italic>TCP</italic> genes (acronym for <italic>TEOSINTE BRANCHED1, CYCLOIDEA</italic>, and <italic>PROLIFERATION CELL FACTOR</italic>) have been poorly studied in Asparagales, the largest order of monocots that includes both bilateral flowers in Orchidaceae (ca. 25.000 spp) and radially symmetrical flowers in Hypoxidaceae (ca. 200 spp). With the aim of assessing <italic>TCP</italic> gene evolution in the Asparagales, we isolated <italic>TCP-like</italic> genes from publicly available databases and our own transcriptomes of <italic>Cattleya trianae</italic> (Orchidaceae) and <italic>Hypoxis decumbens</italic> (Hypoxidaceae). Our matrix contains 452 sequences representing the three major clades of <italic>TCP</italic> genes. Besides the previously identified <italic>CYC</italic> specific core eudicot duplications, our ML phylogenetic analyses recovered an early <italic>CIN-like</italic> duplication predating all angiosperms, two <italic>CIN-like</italic> Asparagales-specific duplications and a duplication prior to the diversification of Orchidoideae and Epidendroideae. In addition, we provide evidence of at least three duplications of <italic>PCF-like</italic> genes in Asparagales. While <italic>CIN-like</italic> and <italic>PCF-like</italic> genes have multiplied in Asparagales, likely enhancing the genetic network for cell proliferation, <italic>CYC-like</italic> genes remain as single, shorter copies with low expression. Homogeneous expression of <italic>CYC-like</italic> genes in the labellum as well as the lateral petals suggests little contribution to the bilateral perianth in <italic>C. trianae</italic>. <italic>CIN-like</italic> and <italic>PCF-like</italic> gene expression suggests conserved roles in cell proliferation in leaves, sepals and petals, carpels, ovules and fruits in Asparagales by comparison with previously reported functions in core eudicots and monocots. This is the first large scale analysis of <italic>TCP-like</italic> genes in Asparagales that will serve as a platform for in-depth functional studies in emerging model monocots.</p>