Phylogenomics Reveals an Ancient Hybrid Origin of the Persian Walnut
Phylogenomics Reveals an Ancient Hybrid Origin of the Persian Walnut
复制标题
系统基因组学揭示了波斯核桃的古老杂交起源
DOI：
10.1093/molbev/msz112
复制
发表时间：
2019-11-01
影响因子：
10.7
通讯作者：
Bai, Wei-Ning
中科院分区：
文献类型：
--
作者：
Zhang, Bo-Wen;Xu, Lin-Lin;Bai, Wei-Ning
核桃（Juglans regia）因其高品质的木材和坚果而在世界范围内种植，但其起源仍然是神秘的，因为在美国黑核桃和亚洲胡桃之间，它占据了一个悬而未决的位置。同样不清楚的是唯一的美国胡桃，J. cinerea的起源。我们对22种核桃中的19种的80个个体的全基因组进行了重测序，并组装了其近亲枫杨和化香的基因组。使用单拷贝核基因的遗传网络分析，全基因组位点模式概率和近似贝叶斯计算，我们发现，J. regia（及其地方品种J. sigillata）是美洲和亚洲血统之间的杂交种，而J. cinerea是由移民亚洲胡桃到美国黑胡桃基因组中的大规模基因渗入造成的。近似的贝叶斯计算模型将混合起源置于上新世晚期，类似于3.45 My，两个父母血统都在欧洲灭绝。
Persian walnut (Juglans regia) is cultivated worldwide for its high-quality wood and nuts, but its origin has remained mysterious because in phylogenies it occupies an unresolved position between American black walnuts and Asian butternuts. Equally unclear is the origin of the only American butternut, J. cinerea. We resequenced the whole genome of 80 individuals from 19 of the 22 species of Juglans and assembled the genome of its relatives Pterocarya stenoptera and Platycarya strobilacea. Using phylogenetic-network analysis of single-copy nuclear genes, genome-wide site pattern probabilities, and Approximate Bayesian Computation, we discovered that J. regia (and its landrace J. sigillata) arose as a hybrid between the American and the Asian lineages and that J. cinerea resulted from massive introgression from an immigrating Asian butternut into the genome of an American black walnut. Approximate Bayesian Computation modeling placed the hybrid origin in the late Pliocene, similar to 3.45 My, with both parental lineages since having gone extinct in Europe.