北京大学现代农业研究院何航、张兴平等报道了西瓜端粒-端粒超级泛基因组。相关论文发表在2024年7月8日出版的《自然-遗传学》杂志上。

为了破译葫芦科西瓜属植物的遗传多样性，研究人员绘制了27个不同组合基因型的端粒到端粒（T2T）图谱，其中包括所有七个西瓜属植物物种。这个T2T超级泛基因组扩展了之前发表的参考基因组T2T-G42，容量增大了399.2Mb和增加了11,225个基因。比较分析揭示的基因变异和结构变异（SV），揭示了西瓜的进化和驯化过程，这些进化和驯化过程提高了西瓜的苦味和含糖量等特性，同时削弱了西瓜的抗病性。

将C. amarus和Citrullus mucospermus的多抗病基因座成功引入栽培的Citrullus lanatus。在C. lanatus中发现的SVs不仅遗传自cordophanus，还遗传自C. mucospermus，这表明在栽培西瓜物种中，除了cordophanus还有其他祖先。该研究大大提高了对西瓜基因组多样性的理解，为所有西瓜物种提供了全面的参考基因组。这一进展有助于利用西瓜的野生近缘株对西瓜进行探索和遗传改良。

附：英文原文

Title: Telomere-to-telomere Citrullus super-pangenome provides direction for watermelon breeding

Author: Zhang, Yilin, Zhao, Mingxia, Tan, Jingsheng, Huang, Minghan, Chu, Xiao, Li, Yan, Han, Xue, Fang, Taohong, Tian, Yao, Jarret, Robert, Lu, Dongdong, Chen, Yijun, Xue, Lifang, Li, Xiaoni, Qin, Guochen, Li, Bosheng, Sun, Yudong, Deng, Xing Wang, Deng, Yun, Zhang, Xingping, He, Hang

Issue&Volume: 2024-07-08

Abstract: To decipher the genetic diversity within the cucurbit genus Citrullus, we generated telomere-to-telomere (T2T) assemblies of 27 distinct genotypes, encompassing all seven Citrullus species. This T2T super-pangenome has expanded the previously published reference genome, T2T-G42, by adding 399.2Mb and 11,225 genes. Comparative analysis has unveiled gene variants and structural variations (SVs), shedding light on watermelon evolution and domestication processes that enhanced attributes such as bitterness and sugar content while compromising disease resistance. Multidisease-resistant loci from Citrullus amarus and Citrullus mucosospermus were successfully introduced into cultivated Citrullus lanatus. The SVs identified in C. lanatus have not only been inherited from cordophanus but also from C. mucosospermus, suggesting additional ancestors beyond cordophanus in the lineage of cultivated watermelon. Our investigation substantially improves the comprehension of watermelon genome diversity, furnishing comprehensive reference genomes for all Citrullus species. This advancement aids in the exploration and genetic enhancement of watermelon using its wild relatives.

DOI: 10.1038/s41588-024-01823-6

Source: https://www.nature.com/articles/s41588-024-01823-6