Expression Pattern Analyzation and Regulation Genes Identification on the Purple Phenotype in the Different Tissues of the Purple Pak-choi and Zicaitai

Among the <i>Brassica</i> species in China, including Chinese cabbage, pak-choi, caixin, zicaitai, and wucai, <i>Brassica rapa</i> plays an important role in vegetable production. Purple resources from the species itself are scarce. It is worth noting that the tissue position...

Full description

Saved in:
Bibliographic Details
Main Authors: Yating Zhu, Xia Wang, Xiuping Tu, Shujiang Zhang, Shifan Zhang, Hui Zhang, Rifei Sun, Xiuxiu Xu, Xinyu Gao, Guoliang Li, Fei Li
Format: Article
Language:English
Published: MDPI AG 2025-01-01
Series:Horticulturae
Subjects:
Online Access:https://www.mdpi.com/2311-7524/11/2/109
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Among the <i>Brassica</i> species in China, including Chinese cabbage, pak-choi, caixin, zicaitai, and wucai, <i>Brassica rapa</i> plays an important role in vegetable production. Purple resources from the species itself are scarce. It is worth noting that the tissue positions expressing a purple phenotype vary greatly between purple pak-choi and zicaitai. In this study, the genetic patterns of the purple phenotype were analyzed in purple pak-choi and zicaitai, and the F<sub>1</sub> showed purple leaves and green stems, which indicated that purple traits in the leaves and stem were inherited independently. In conjunction with field identification, RNA-seq was used to sequence the transcriptomes of the purple expression sites of purple pak-choi, zicaitai, and their F<sub>1</sub>. The high expression of the regulatory genes <i>Dark_pur</i> and <i>BrTT8</i> affected the purple color of pak-choi and caused the high expression of structural genes of the anthocyanin metabolism pathway and the accumulation of anthocyanins in leaves. The regulatory genes <i>BrPAP<sub>2</sub></i> and <i>BrTT8</i> affected the purple color of zicaitai stems, were significantly upregulated, and caused high expression of related structural genes, leading to the accumulation of anthocyanins in the stem epidermis. This suggested that <i>BrPAP<sub>2</sub></i> and <i>Dark_pur</i> were both R2R3-MYB transcription factors, which were tissue-specific for the regulation of purple color traits in <i>B. rapa</i>. They also had a gene epistatic effect, which influenced the expression of purple traits in the F<sub>1</sub>. The gene <i>MYBL2</i> was highly expressed in all purple tissue sites. The present study on the regulatory genes of the purple phenotype of zicaitai and purple pak-choi provides a theoretical basis for revealing the influence of purple traits on <i>B. rapa</i> leaves and stems, and it may lay the foundation for the selection and breeding of purple vegetables of <i>B. rapa</i>.
ISSN:2311-7524