近日，华中农业大学教授金双侠及其研究小组发现，两个异源四倍体棉花种质的基因组组装揭示了体细胞胚胎发生机制，并实现了精确的基因组编辑。相关论文于2025年7月22日发表在《自然—遗传学》杂志上。

在这里，课题组研究人员提出了端粒到端粒的组装Jin668和高质量的组装YZ1，两个高度再生的异源四倍体棉花种质。Jin668基因组的完成使约30.1Mb玉米的着丝粒反转录转座子和Tekay的反转录转座子侵入着丝粒区域，包含25190个拷贝的约8.1 Mb 5S rDNA阵列，以及含有8131个拷贝的约75.1 Mb主要45S rDNA阵列。再生和顽固性基因型的比较分析揭示了在初始再生过程中的动态转录模式和染色质可及性。分层基因调控网络确定AGL15是再生的贡献者。此外，该研究组证明了遗传变异会影响sgRNA靶点，而Jin668基因组组装降低了基于CRISPR的基因组编辑中脱靶效应的风险。总之，完整的Jin668基因组揭示了基因组区域和棉花再生的复杂性，提高了基因组编辑的精度。

据介绍，体细胞胚胎发生对植物基因工程至关重要，但棉花的潜在机制仍然知之甚少。

附：英文原文

Title: Genome assembly of two allotetraploid cotton germplasms reveals mechanisms of somatic embryogenesis and enables precise genome editing

Author: Xu, Zhongping, Wang, Guanying, Zhu, Xiangqian, Wang, Ruipeng, Zhu, Longfu, Tu, Lili, Liu, Yuling, Peng, Renhai, Lindsey, Keith, Wang, Maojun, Zhang, Xianlong, Jin, Shuangxia

Issue&Volume: 2025-07-22

Abstract: Somatic embryogenesis is crucial for plant genetic engineering, yet the underlying mechanisms in cotton remain poorly understood. Here we present a telomere-to-telomere assembly of Jin668 and a high-quality assembly of YZ1, two highly regenerative allotetraploid cotton germplasms. The completion of the Jin668 genome enables characterization of ~30.1Mb of centromeric regions invaded by centromeric retrotransposon of maize and Tekay retrotransposons, an ~8.1Mb 5S rDNA array containing 25,190 copies and a ~75.1Mb major 45S rDNA array with 8,131 copies. Comparative analyses of regenerative and recalcitrant genotypes reveal dynamic transcriptional patterns and chromatin accessibility during the initial regeneration process. A hierarchical gene regulatory network identifies AGL15 as a contributor to regeneration. Additionally, we demonstrate that genetic variation affects sgRNA target sites, while the Jin668 genome assembly reduces the risk of off-target effects in CRISPR-based genome editing. Together, the complete Jin668 genome reveals the complexity of genomic regions and cotton regeneration, and improves the precision of genome editing.

DOI: 10.1038/s41588-025-02258-3

Source: https://www.nature.com/articles/s41588-025-02258-3