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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Duplication and expression of horizontally transferred polygalacturonase genes is associated with host range expansion of mirid bugs
AU - Xu, P.
AU - Lu, B.
AU - Liu, J.
AU - Chao, J.
AU - Donkersley, P.
AU - Holdbrook, R.
AU - Lu, Y.
PY - 2019/1/9
Y1 - 2019/1/9
N2 - Background: Horizontal gene transfer and gene duplication are two major mechanisms contributing to the evolutionary adaptation of organisms. Previously, polygalacturonase genes (PGs) were independently horizontally transferred and underwent multiple duplications in insects (e.g., mirid bugs and beetles). Here, we chose three phytozoophagous mirid bugs (Adelphocoris suturalis, A. fasciaticollis, A. lineolatus) and one zoophytophagous mirid bug (Nesidiocoris tenuis) to detect whether the duplication, molecular evolution, and expression levels of PGs were related to host range expansion in mirid bugs. Results: By RNA-seq, we reported 30, 20, 19 and 8 PGs in A. suturalis, A. fasciaticollis, A. lineolatus and N. tenuis, respectively. Interestingly, the number of PGs was significantly positive correlation to the number of host plants (P = 0.0339) in mirid bugs. Most PGs (> 17) were highly expressed in the three phytozoophagous mirid bugs, while only one PG was relatively highly expressed in the zoophytophagous mirid bug. Natural selection analysis clearly showed that a significant relaxation of selection pressure acted on the PGs in zoophytophagous mirid bugs (K = 0.546, P = 0.0158) rather than in phytozoophagous mirid bugs (K = 1, P = 0.92), suggesting a function constraint of PGs in phytozoophagous mirid bugs. Conclusion: Taken together with gene duplication, molecular evolution, and expression levels, our results suggest that PGs are more strictly required by phytozoophagous than by zoophytophagous mirid bugs and that the duplication of PGs is associated with the expansion of host plant ranges in mirid bugs. © 2019 The Author(s).
AB - Background: Horizontal gene transfer and gene duplication are two major mechanisms contributing to the evolutionary adaptation of organisms. Previously, polygalacturonase genes (PGs) were independently horizontally transferred and underwent multiple duplications in insects (e.g., mirid bugs and beetles). Here, we chose three phytozoophagous mirid bugs (Adelphocoris suturalis, A. fasciaticollis, A. lineolatus) and one zoophytophagous mirid bug (Nesidiocoris tenuis) to detect whether the duplication, molecular evolution, and expression levels of PGs were related to host range expansion in mirid bugs. Results: By RNA-seq, we reported 30, 20, 19 and 8 PGs in A. suturalis, A. fasciaticollis, A. lineolatus and N. tenuis, respectively. Interestingly, the number of PGs was significantly positive correlation to the number of host plants (P = 0.0339) in mirid bugs. Most PGs (> 17) were highly expressed in the three phytozoophagous mirid bugs, while only one PG was relatively highly expressed in the zoophytophagous mirid bug. Natural selection analysis clearly showed that a significant relaxation of selection pressure acted on the PGs in zoophytophagous mirid bugs (K = 0.546, P = 0.0158) rather than in phytozoophagous mirid bugs (K = 1, P = 0.92), suggesting a function constraint of PGs in phytozoophagous mirid bugs. Conclusion: Taken together with gene duplication, molecular evolution, and expression levels, our results suggest that PGs are more strictly required by phytozoophagous than by zoophytophagous mirid bugs and that the duplication of PGs is associated with the expansion of host plant ranges in mirid bugs. © 2019 The Author(s).
KW - Expression
KW - Gene duplication
KW - Host range expansion
KW - Molecular evolution
KW - Polygalacturonase
KW - Adelphocoris suturalis
KW - Coleoptera
KW - Hexapoda
KW - Miridae
U2 - 10.1186/s12862-019-1351-1
DO - 10.1186/s12862-019-1351-1
M3 - Journal article
VL - 19
JO - BMC Evolutionary Biology
JF - BMC Evolutionary Biology
SN - 1471-2148
IS - 1
M1 - 12
ER -