Genetic mapping and candidate gene identification of BoGL5, a gene essential for cuticular wax biosynthesis in broccoli

BMC Genomics

Jingjing Huang¹  Honghao Lv¹  Zhiyuan Fang¹  Zhansheng Li¹  Yangyong Zhang¹  Limei Yang¹  Yumei Liu¹  Mu Zhuang¹  Jialei Ji¹  Fengqing Han¹  Qi Xie¹  Yong Wang¹ 

[1] Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, #12 Zhong Guan Cun Nandajie Street, 100081, Beijing, China;

关键词: Cuticular wax;    Broccoli;    Fine mapping;    Candidate gene;    Functional analysis;   

DOI  :  10.1186/s12864-021-08143-7

来源: Springer

【 摘 要 】

BackgroundThe aerial organs of most terrestrial plants are covered by cuticular waxes, which impart plants a glaucous appearance and play important roles in protecting against various biotic and abiotic stresses. Despite many glossy green (wax-defective) mutants being well characterized in model plants, little is known about the genetic basis of glossy green mutant in broccoli.ResultsB156 is a spontaneous broccoli mutant showing a glossy green phenotype. Detection by scanning electron microscopy (SEM) and chromatography-mass spectrometry (GC-MS) revealed that B156 is a cuticular wax-defective mutant, lacking waxes mostly longer than C28. Inheritance analysis revealed that this trait was controlled by a single recessive gene, BoGL5. Whole-genome InDel markers were developed, and a segregating F2 population was constructed to map BoGL5. Ultimately, BoGL5 was mapped to a 94.1 kb interval on C01. The BoCER2 gene, which is homologous to the Arabidopsis CER2 gene, was identified as a candidate of BoGL5 from the target interval. Sequence analyses revealed that Bocer2 in B156 harbored a G-to-T SNP mutation at the 485th nucleotide of the CDS, resulting in a W-to-L transition at the 162nd amino acid, a conserved site adjacent to an HXXXD motif of the deduced protein sequence. Expression analysis revealed that BoCER2 was significantly down-regulated in the leaves, stems, and siliques of B156 mutant than that of B3. Last, ectopic expression of BoCER2 in A. thaliana could, whereas Bocer2 could not, rescue the phenotype of cer2 mutant.ConclusionsOverall, this study mapped the locus determining glossy phenotype of B156 and proved BoCER2 is functional gene involved in cuticular wax biosynthesis which would promotes the utilization of BoCER2 to enhance plant resistance to biotic and abiotic stresses, and breeding of B. oleracea cultivars with glossy traits.

【 授权许可】

CC BY