Journal Article

Unzipped chromosome-level genomes reveal allopolyploid nematode origin pattern as unreduced gamete hybridization

Wang, Xueyu, Cui, Simeng, Xie, Chuanshuai, Mao, Shengqiang, Dai, Dadong, Li, Fanling, Zheng, Jinshui, Zhang, Shurong, Sun, Ming, Peng, Donghai, Bo, Dexin, Zhu, Zhaolu, Zhou, Yayi, Liao, Yucheng

2023

Overview

The formation and consequences of polyploidization in animals with clonal reproduction remain largely unknown. Clade I root-knot nematodes (RKNs), characterized by parthenogenesis and allopolyploidy, show a widespread geographical distribution and extensive agricultural destruction. Here, we generated 4 unzipped polyploid RKN genomes and identified a putative novel alternative telomeric element. Then we reconstructed 4 chromosome-level assemblies and resolved their genome structures as AAB for triploid and AABB for tetraploid. The phylogeny of subgenomes revealed polyploid RKN origin patterns as hybridization between haploid and unreduced gametes. We also observed extensive chromosomal fusions and homologous gene expression decrease after polyploidization, which might offset the disadvantages of clonal reproduction and increase fitness in polyploid RKNs. Our results reveal a rare pathway of polyploidization in parthenogenic polyploid animals and provide a large number of high-precision genetic resources that could be used for RKN prevention and control. The occurrence and consequences of polyploidization in clonally reproducing animals is unclear. Here, the authors generate 4 polyploid Meloidogyne genomes, identifying a telomeric element, resolving genome structures and extensive chromosome fusion events, and revealing origin patterns.

• Publisher: Nature Publishing Group UK,Nature Portfolio
• Subject: 45/22 / 45/23 / 45/90 / 45/91 / 631/181/759 / 631/208/742 / 631/208/8 / 631/80/103/560 / Humanities and Social Sciences / multidisciplinary / Science / Science (multidisciplinary)