Premium
Gene copy number variations as signatures of adaptive evolution in the parthenogenetic, plant‐parasitic nematode Meloidogyne incognita
Author(s) -
CastagSereno Philippe,
Mulet Karine,
Danchin Etienne G. J.,
Koutsovoulos Georgios D.,
Karaulic Mégane,
Da Rocha Martine,
BaillyBechet Marc,
Pratx Loris,
PerfusBarbeoch Laetitia,
Abad Pierre
Publication year - 2019
Publication title -
molecular ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.619
H-Index - 225
eISSN - 1365-294X
pISSN - 0962-1083
DOI - 10.1111/mec.15095
Subject(s) - biology , meloidogyne incognita , nematode , adaptation (eye) , terra incognita , genetics , parthenogenesis , genetic variation , host adaptation , asexual reproduction , host (biology) , copy number variation , gene , experimental evolution , evolutionary biology , genome , ecology , embryo , neuroscience
Adaptation to changing environmental conditions represents a challenge to parthenogenetic organisms, and until now, how phenotypic variants are generated in clones in response to the selection pressure of their environment remains poorly known. The obligatory parthenogenetic root‐knot nematode species Meloidogyne incognita has a worldwide distribution and is the most devastating plant‐parasitic nematode. Despite its asexual reproduction, this species exhibits an unexpected capacity of adaptation to environmental constraints, for example, resistant hosts. Here, we used a genomewide comparative hybridization strategy to evaluate variations in gene copy numbers between genotypes of M. incognita resulting from two parallel experimental evolution assays on a susceptible vs. resistant host plant. We detected gene copy number variations ( CNV s) associated with the ability of the nematodes to overcome resistance of the host plant, and this genetic variation may reflect an adaptive response to host resistance in this parthenogenetic species. The CNV distribution throughout the nematode genome is not random and suggests the occurrence of genomic regions more prone to undergo duplications and losses in response to the selection pressure of the host resistance. Furthermore, our analysis revealed an outstanding level of gene loss events in nematode genotypes that have overcome the resistance. Overall, our results support the view that gene loss could be a common class of adaptive genetic mechanism in response to a challenging new biotic environment in clonal animals.