State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Laboratory for Lingnan Modern Agriculture, Key Laboratory of Biology and Germplasm Enhancement of Horticultural Crops, Ministry of Agriculture and Rural Affairs, Guangdong Litchi Engineering Research Center, College of Horticulture, South China Agricultural University, Guangzhou, China.
Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization, Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of Tropical and Subtropical Fruit Tree Research, Guangzhou, China.
Nat Genet. 2022 Jan;54(1):73-83. doi: 10.1038/s41588-021-00971-3. Epub 2022 Jan 3.
Lychee is an exotic tropical fruit with a distinct flavor. The genome of cultivar 'Feizixiao' was assembled into 15 pseudochromosomes, totaling ~470 Mb. High heterozygosity (2.27%) resulted in two complete haplotypic assemblies. A total of 13,517 allelic genes (42.4%) were differentially expressed in diverse tissues. Analyses of 72 resequenced lychee accessions revealed two independent domestication events. The extremely early maturing cultivars preferentially aligned to one haplotype were domesticated from a wild population in Yunnan, whereas the late-maturing cultivars that mapped mostly to the second haplotype were domesticated independently from a wild population in Hainan. Early maturing cultivars were probably developed in Guangdong via hybridization between extremely early maturing cultivar and late-maturing cultivar individuals. Variable deletions of a 3.7 kb region encompassed by a pair of CONSTANS-like genes probably regulate fruit maturation differences among lychee cultivars. These genomic resources provide insights into the natural history of lychee domestication and will accelerate the improvement of lychee and related crops.
荔枝是一种具有独特风味的热带外来水果。品种“妃子笑”的基因组被组装成 15 条假染色体，总长约 470Mb。高杂合性（2.27%）导致了两个完整的单倍型组装。在不同组织中，共检测到 13517 个等位基因（42.4%）存在差异表达。对 72 个重测序的荔枝样本的分析揭示了两次独立的驯化事件。极早熟品种优先与一个单倍型匹配，是从云南的野生种群中驯化而来的，而晚熟品种则主要与第二个单倍型匹配，是从海南的野生种群中独立驯化而来的。早熟品种可能是在广东通过极早熟品种和晚熟品种个体之间的杂交培育而成的。一对 CONSTANS 样基因之间包含的 3.7kb 区域的可变缺失可能调节了荔枝品种间果实成熟的差异。这些基因组资源为荔枝驯化的自然历史提供了深入了解，并将加速荔枝和相关作物的改良。
