BrCPS1 Function in Leafy Head Formation Was Verified by Two Allelic Mutations in Chinese Cabbage (Brassica rapa L. ssp. pekinensis)

Yue Gao; Gaoyang Qu; Shengnan Huang; Zhiyong Liu; Wei Fu; Meidi Zhang; Hui Feng

doi:10.3389/fpls.2022.889798

BrCPS1 Function in Leafy Head Formation Was Verified by Two Allelic Mutations in Chinese Cabbage (Brassica rapa L. ssp. pekinensis)

Front Plant Sci. 2022 Jul 12:13:889798. doi: 10.3389/fpls.2022.889798. eCollection 2022.

Authors

Yue Gao^{1

2}, Gaoyang Qu², Shengnan Huang², Zhiyong Liu², Wei Fu², Meidi Zhang², Hui Feng²

Affiliations

¹ College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, China.
² Liaoning Key Laboratory of Genetics and Breeding for Cruciferous Vegetable Crops, College of Horticulture, Shenyang Agricultural University, Shenyang, China.

Abstract

The formation of the leafy heads of Chinese cabbage is an important agricultural factor because it directly affects yield. In this study, we identified two allelic non-heading mutants, nhm4-1 and nhm4-2, from an ethyl methanesulfonate mutagenic population of a heading Chinese cabbage double haploid line "FT." Using MutMap, Kompetitive Allele-Specific PCR genotyping, and map-based cloning, we found that BraA09g001440.3C was the causal gene for the mutants. BraA09g001440.3C encodes an ent-copalyl diphosphate synthase 1 involved in gibberellin biosynthesis. A single non-synonymous SNP in the seventh and fourth exons of BraA09g001440.3C was responsible for the nhm4-1 and nhm4-2 mutant phenotypes, respectively. Compared with the wild-type "FT," the gibberellin content in the mutant leaves was significantly reduced. Both mutants showed a tendency to form leafy heads after exogenous GA₃ treatment. The two non-heading mutants and the work presented herein demonstrate that gibberellin is related to leafy head formation in Chinese cabbage.

Keywords: CPS1; Chinese cabbage; MutMap; allelic mutations; leafy head formation.