Cloning and Characterization of 12 TCP Genes in Medicinal Plant Plantago asiatica via De Novo Transcriptome Assembly

<b>Background:</b><i>Plantago asiatica</i> (<i>P. asiatica</i>) is an important Chinese traditional medicinal plant of the family Plantaginaceae and widely used in pharmaceutical industries. TCP transcription factors play an important role in plant development, but a limited number of studies on this have been reported in <i>P. asiatica.</i><b>Methods:</b> Since genome assembly was not available, in this study, we used the de novo transcriptome assembly method to genome-wide-characterize the TCP gene family in <i>P. asiatica</i>. Up to 70.7 M high-quality paired-end reads were generated after sequencing and a total of 12 TCP genes were cloned by the predicted bioinformatic results, which were named <i>PaTCP1-12</i>. <b>Results:</b> Phylogenetic tree, motif analysis and subcellular localization results revealed that these <i>PaTCPs</i> were conserved compared to those from the model plant, <i>Arabidopsis</i>. Expression analysis suggested that most of the TCPs were highly expressed in both the leaf and root, while <i>PaTCP1</i>, <i>PaTCP6</i> and <i>PaTCP9</i> could also be detected in the seed. <b>Conclusions:</b> Since seed characteristics are one of the main agronomical traits in <i>P. asiatica</i>, the finding of <i>PaTCP1</i>, <i>PaTCP6</i> and <i>PaTCP9</i> expression patterns in the stem suggested an important role for further plant improvement.