A transposon DNA/hAT-Ac insertion promotes the formation of yellow tepals in lotus (Nelumbo)

Ping Zhou; Huiyan Jiang; Jingwen Li; Xinrui He; Qijiang Jin; Yanjie Wang; Yingchun Xu

doi:10.1016/j.ijbiomac.2024.137724

A transposon DNA/hAT-Ac insertion promotes the formation of yellow tepals in lotus (Nelumbo)

Int J Biol Macromol. 2024 Nov 22;283(Pt 4):137724. doi: 10.1016/j.ijbiomac.2024.137724. Online ahead of print.

Authors

Ping Zhou¹, Huiyan Jiang², Jingwen Li², Xinrui He², Qijiang Jin², Yanjie Wang², Yingchun Xu³

Affiliations

¹ Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China; Sanya Research Institute of Nanjing Agricultural University, Sanya 572000, China; College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China.
² Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China; Sanya Research Institute of Nanjing Agricultural University, Sanya 572000, China.
³ Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China; Sanya Research Institute of Nanjing Agricultural University, Sanya 572000, China. Electronic address: xyc@njau.edu.cn.

PMID: 39577531
DOI: 10.1016/j.ijbiomac.2024.137724

Abstract

Yellow tepal is a unique trait of the American lotus (Nelumbo lutea), and all yellow lotus cultivars in the market possess genetic material from the American lotus. However, the formation of yellow tepals in lotus and the genetic mechanism of their formation remain unclear. In this study, we identified a transposon DNA/hAT-Ac, located within the promoter region of an R2R3-MYB transcription factor, MYB12, by comparing the insertion patterns of transposons in the genomes of American and Asian lotus (Nelumbo nucifera). The transposon was found exclusively in yellow lotus cultivars and not in red or white lotus. The insertion of DNA/hAT-Ac facilitated the specific expression of MYB12 in the yellow lotus tepals. Transient expression in lotus tepals, dual-luciferase, and yeast one-hybrid assays demonstrated that MYB12 promotes the accumulation of carotenoids and flavonols by activating the expression of genes involved in carotenoid and flavonols biosynthesis, and it directly binds to the promoters of PSY and FLS. Our results indicated that the transposon DNA/hAT-Ac-mediated specific expression of MYB12 is crucial for the formation of yellow tepals in lotus, and the findings provide a theoretical basis for the breeding of yellow lotus cultivars.

Keywords: Carotenoids; Flavonols; Lotus (Nelumbo); MYB12; Transposon DNA/hAT-ac; Yellow tepal.