The bottle gourd genome provides insights into Cucurbitaceae evolution and facilitates mapping of a Papaya ring‐spot virus resistance locus. (12th November 2017)

• Record Type: Journal Article
• Authors: Wu, Shan; Shamimuzzaman, Md; Sun, Honghe; Salse, Jerome; Sui, Xuelian; Wilder, Alan; Wu, Zujian; Levi, Amnon; Xu, Yong; Ling, Kai‐Shu; Fei, Zhangjun
• Is Part Of: Plant journal. Volume 92:Number 5(2017)
• Page Start: 963
• Page End: 975
• Publication Date: 2017-11-12
• Subjects: bottle gourd -- Lagenaria siceraria -- genome sequencing -- cucurbit genome evolution -- Papaya ring‐spot virus resistance; Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.13722
• Languages: English
• ISSNs: 0960-7412

Abstract

Summary: Bottle gourd ( Lagenaria siceraria ) is an important vegetable crop as well as a rootstock for other cucurbit crops. In this study, we report a high‐quality 313.4‐Mb genome sequence of a bottle gourd inbred line, USVL1VR‐Ls, with a scaffold N50 of 8.7 Mb and the longest of 19.0 Mb. About 98.3% of the assembled scaffolds are anchored to the 11 pseudomolecules. Our comparative genomic analysis identifies chromosome‐level syntenic relationships between bottle gourd and other cucurbits, as well as lineage‐specific gene family expansions in bottle gourd. We reconstructed the genome of the most recent common ancestor of Cucurbitaceae, which revealed that the ancestral Cucurbitaceae karyotypes consisted of 12 protochromosomes with 18 534 protogenes. The 12 protochromosomes are largely retained in the modern melon genome, while have undergone different degrees of shuffling events in other investigated cucurbit genomes. The 11 bottle gourd chromosomes derive from the ancestral Cucurbitaceae karyotypes followed by 19 chromosomal fissions and 20 fusions. The bottle gourd genome sequence has facilitated the mapping of a dominant monogenic locus, Prs, conferring Papaya ring‐spot virus (PRSV) resistance in bottle gourd, to a 317.8‐kb region on chromosome 1. We have developed a cleaved amplified polymorphic sequence (CAPS) marker tightly linked to the Prs locus and demonstrated its potential application in marker‐assisted selection of PRSV resistance in bottle gourd. This study provides insights into the paleohistory of Cucurbitaceae genome evolution, and the high‐quality genome sequence of bottle gourd provides a useful resource for plant comparative genomics studies and cucurbit improvement. Significance Statement: The high‐quality reference genome of bottle gourd is a useful resource for the improvement of this crop and for studying the evolutionary history of the Cucurbitaceae family. We demonstrate that the reported bottle gourd genome facilitates the comparative genomics analysis leading to the construction of ancestral chromosomes of Cucurbitaceae, and enables the mapping of a locus conferring resistance to Papaya ringspot virus in bottle gourd.