The function of BoTCP25 in the regulation of leaf development of Chinese kale

• Published in: Frontiers in plant science Vol. 14; p. 1127197
• Main Authors: Zeng, Jiajing, Yang, Mengyu, Deng, Jing, Zheng, Dongyang, Lai, Zhongxiong, Wang-Pruski, Gefu, XuHan, Xu, Guo, Rongfang
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 18-04-2023
• Subjects: BoNGA3; BoTCP25; Chinese kale; leaf; metamorphic leaf; Plant Science; BoNGA3; metamorphic leaf; BoTCP25; leaf; Chinese kale
• ISSN: 1664-462X; 1664-462X
• DOI: 10.3389/fpls.2023.1127197

XG Chinese kale (
cv. '
') is a variety of Chinese kale and has metamorphic leaves attached to the true leaves. Metamorphic leaves are secondary leaves emerging from the veins of true leaves. However, it remains unknown how the formation of metamorphic leaves is regulated and whether it differs from normal leaves.
is differentially expressed in different parts of XG leaves and respond to auxin signals. To clarify the function of BoTCP25 in XG Chinese kale leaves, we overexpressed
in XG and
, and interestingly, its overexpression caused Chinese kale leaves to curl and changed the location of metamorphic leaves, whereas heterologous expression of
in
did not show metamorphic leaves, but only an increase in leaf number and leaf area. Further analysis of the expression of related genes in Chinese kale and
overexpressing
revealed that BoTCP25 could directly bind the promoter of
, a transcription factor related to leaf development, and induce a significant expression of
in transgenic Chinese kale plants, whereas this induction of
did not occur in transgenic
. This suggests that the regulation of Chinese kale metamorphic leaves by BoTCP25 is dependent on a regulatory pathway or elements specific to XG and that this regulatory element may be repressed or absent from
. In addition, the expression of miR319's precursor, a negative regulator of
, also differed in transgenic Chinese kale and
. miR319's transcrips were significantly up-regulated in transgenic Chinese kale mature leaves, while in transgenic
, the expression of miR319 in mature leaves was kept low. In conclusion, the differential expression of
and miR319 in the two species may be related to the exertion of BoTCP25 function, thus partially contributing to the differences in leaf phenotypes between overexpressed
in
and Chinese kale.