An Optimized Transformation System and Functional Test of <i>CYC</i>-Like TCP Gene <i>CpCYC</i> in <i>Chirita pumila</i> (Gesneriaceae)

• Main Authors: Jing Liu, Juan-Juan Wang, Jie Wu, Yang Wang, Qi Liu, Fang-Pu Liu, Xia Yang, Yin-Zheng Wang
• Format: Article
• Language: English
• Published: MDPI AG 2021-04-01
• Series: International Journal of Molecular Sciences
• Subjects: <i>Chirita pumila</i>; <i>CpCYC</i>; evo-devo; functional test; genetic transformation; Gesneriaceae
• Online Access: https://www.mdpi.com/1422-0067/22/9/4544

The development of an ideal model plant located at a key phylogenetic node is critically important to advance functional and regulatory studies of key regulatory genes in the evolutionary developmental (evo-devo) biology field. In this study, we selected <i>Chirita pumila</i> in the family Gesneriaceae, a basal group in Lamiales, as a model plant to optimize its genetic transformation system established previously by us through investigating a series of factors and further conduct functional test of the <i>CYC</i>-like floral symmetry gene <i>CpCYC</i>. By transforming a RNAi:CpCYC vector, we successfully achieved the desired phenotypes of upright actinomorphic flowers, which suggest that <i>CpCYC</i> actually determines the establishment of floral zygomorphy and the horizontal orientation of flowers in <i>C</i>. <i>pumila</i>. We also confirmed the activities of <i>CpCYC</i> promoter in dorsal petals, dorsal/lateral staminodes, as well as the pedicel by transferring a <i>CpCYC</i> promoter:GUS vector into <i>C</i>. <i>pumila</i>. Furthermore, we testified the availability of a transient gene expression system using <i>C</i>. <i>pumila</i> mesophyll protoplasts. The improved transformation system together with the inherent biological features would make <i>C. pumila</i> an attractive new model in functional and regulatory studies for a broad range of evo-devo issues.