AUTHOR=Wei Xinrui , Yuan Meng , Zheng Bao-Qiang , Zhou Lin , Wang Yan 

TITLE=Genome-wide identification and characterization of TCP gene family in Dendrobium nobile and their role in perianth development

JOURNAL=Frontiers in Plant Science

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2024.1352119

DOI=10.3389/fpls.2024.1352119

ISSN=1664-462X

ABSTRACT=<p>TCP is a widely distributed, essential plant transcription factor that regulates plant growth and development. An in-depth study of <italic>TCP</italic> genes in <italic>Dendrobium nobile</italic>, a crucial parent in genetic breeding and an excellent model material to explore perianth development in <italic>Dendrobium</italic>, has not been conducted. We identified 23 <italic>DnTCP</italic> genes unevenly distributed across 19 chromosomes and classified them as Class I PCF (12 members), Class II: CIN (10 members), and CYC/TB1 (1 member) based on the conserved domain and phylogenetic analysis. Most DnTCPs in the same subclade had similar gene and motif structures. Segmental duplication was the predominant duplication event for <italic>TCP</italic> genes, and no tandem duplication was observed. Seven genes in the CIN subclade had potential miR319 and -159 target sites. Cis-acting element analysis showed that most <italic>DnTCP</italic> genes contained many developmental stress-, light-, and phytohormone-responsive elements in their promoter regions. Distinct expression patterns were observed among the 23 <italic>DnTCP</italic> genes, suggesting that these genes have diverse regulatory roles at different stages of perianth development or in different organs. For instance, <italic>DnTCP4</italic> and <italic>DnTCP18</italic> play a role in early perianth development, and <italic>DnTCP5</italic> and <italic>DnTCP10</italic> are significantly expressed during late perianth development. <italic>DnTCP17</italic>, <italic>20</italic>, <italic>21</italic>, and <italic>22</italic> are the most likely to be involved in perianth and leaf development. <italic>DnTCP11</italic> was significantly expressed in the gynandrium. Specially, MADS-specific binding sites were present in most <italic>DnTCP</italic> genes putative promoters, and two Class I DnTCPs were in the nucleus and interacted with each other or with the MADS-box. The interactions between TCP and the MADS-box have been described for the first time in orchids, which broadens our understanding of the regulatory network of TCP involved in perianth development in orchids.</p>