Skip to content
Open access

Comparative genomics and time-course transcriptomics uncover homoeologous exchange events reshaping glucosinolate metabolism in Brassica napus

Aug 2026 · Molecular Horticulture · Vol 6 · 0 citations · 89 references
Medicine

TL;DR

A chromosome-level genome assembly for ZY821, an elite high-GSL variety, is generated using long-read sequencing and Hi-C scaffolding and uncovered several novel candidate genes implicated in GSL metabolism.

Abstract

Improving glucosinolate (GSL) profiles in rapeseed (Brassica napus)—high in leaves for pathogen resistance but low in seeds for meal quality—is a key breeding goal, yet its genetic basis remains unclear. Here, we present a chromosome-level genome assembly for ZY821, an elite high-GSL variety, generated using long-read sequencing and Hi-C scaffolding. Comparative analysis with the low-GSL variety ZS11 identified three major homoeologous exchange (HE) events and extensive structural variation. Notably, an A09–C09 HE event replaced the low-expression BnaC09.MYB28 allele with the high-expression BnaA09.MYB28 allele, resulting in elevated MYB28s expression and thereby increased GSL accumulation in ZY821, whereas a deletion of BnaA09.MYB28 in ZS11 significantly reduced the expression of multiple putative downstream targets in the GSL biosynthesis pathway, leading to a reduction in GSL content. This mechanism was supported by population-level HE analysis and time-course transcriptomes across 116 RNA-Seq samples. Furthermore, joint differential expression and co-expression network analyses uncovered several novel candidate genes implicated in GSL metabolism. Collectively, our study provides new mechanistic insights into the genetic control of GSL accumulation, with significant implications for breeding optimized GSL profiles.

Read PDF

Similar papers

Open access Jul 2026

Integrated multi-omics analysis reveals candidate genes for cuticular wax biosynthesis and molecular characteristics of a glossy mutant in rapeseed under natural drought stress

Results suggest that the drought response in the glossy mutant involves not only a defective cuticular barrier but also extensive metabolic and signaling reprogramming, which offers a promising approach for developing more sustainable farming methods amid environmental challenges.

Lei Lei, Xianmin Meng, Weirong Wang et al. · 0 citations
Open access Aug 2026

From genome to gene module: decoding the BsAlfin2-BsTT2 regulatory network controlling low temperature-induced anthocyanin biosynthesis in Begonia semperflorens

Begonia semperflorens is an important ornamental plant worldwide, but its practical application is severely limited by low temperature sensitivity. However, the molecular regulatory mechanisms underlying low temperature-induced anthocyanin biosynthesis remain unclear. In this study, we assembled a high-quality chromosome-level B. semperflorens genome. Through genomic and MYB gene family analysis, we identified a key transcription factor BsTT2, which directly binds to the BsDFR promoter and enhances its activity, thereby driving anthocyanin accumulation in B. semperflorens. Furthermore, using BsTT2 as bait, we identified its interacting protein BsAlfin2. Under low temperature-induced reactive oxygen species (ROS) signaling, BsAlfin2 undergoes nuclear translocation and forms a complex with BsTT2, synergistically enhancing the activation of the BsDFR promoter and significantly improving anthocyanin production efficiency. Based on these results, we propose a previously uncharacterized BsAlfin2/BsTT2-BsDFR regulatory module, which reveals a molecular links low-temperature ROS signaling to anthocyanin biosynthesis in B. semperflorens. In summary, this study not only provides chromosome-level genomic resources for B. semperflorens research but also elucidates a key molecular module in low temperature-induced anthocyanin biosynthesis regulatory pathway, laying a theoretical and data foundation for future studies on leaf color improvement and stress resistance breeding in Begonia.

Lingyu Song, Zhirou Liu, Yixue Zhang et al. · 0 citations
Open access Jul 2026

CRISPR/Cas9-mediated mutagenesis of BnaAOG1s reveals functional divergence in silique and seed development in Brassica napus L

Results indicate that BnaAOG1.A03 and BnaAOG1.C03 are not individually essential for silique and seed development in B. napus, providing a valuable case for functional analysis of homologous genes in polyploid crops.

Jiaxu Xiao, Xiaonan Guo, Aoli Liao et al. · 0 citations
Open access Jul 2026

Pan-genomic and transcriptomic analyses reveal subfunctionalization of CBP/p300-like histone acetyltransferases in soybean seed development.

This study provides the first comprehensive panorama of epigenetic regulators in the soybean pan-genome, highlighting wild germplasm as a valuable reservoir for recovering lost alleles (Group2 homologs) and identifying Wm82-HAC1 (Group 1) as a prime target for precision breeding of seed traits.

Chaojun Wang, Dan Huang, Zhicheng Dong et al. · 0 citations