TY - JOUR T1 - A clonally reproducing generalist aphid pest colonises diverse host plants by rapid transcriptional plasticity of duplicated gene clusters JF - bioRxiv DO - 10.1101/063610 SP - 063610 AU - Thomas C. Mathers AU - Yazhou Chen AU - Gemy Kaithakottil AU - Fabrice Legeai AU - Sam T. Mugford AU - Patrice Baa-Puyoulet AU - Anthony Bretaudeau AU - Bernardo Clavijo AU - Stefano Colella AU - Olivier Collin AU - Tamas Dalmay AU - Thomas Derrien AU - Honglin Feng AU - Toni Gabaldón AU - Anna Jordan AU - Irene Julca AU - Graeme J. Kettles AU - Krissana Kowitwanich AU - Dominique Lavenier AU - Paolo Lenzi AU - Sara Lopez-Gomollon AU - Damian Loska AU - Daniel Mapleson AU - Florian Mauster AU - Simon Moxon AU - Daniel R. G. Price AU - Akiko Sugio AU - Manuella van Munster AU - Marilyne Uzest AU - Darren Waite AU - Georg Jander AU - Denis Tagu AU - Alex C. C. Wilson AU - Cock van Oosterhout AU - David Swarbreck AU - Saskia A. Hogenhout Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/07/19/063610.abstract N2 - Background The prevailing paradigm of host-parasite evolution is that arms races lead to increasing specialisation via genetic adaptation. Insect herbivores are no exception, and the majority have evolved to colonise a small number of closely related host species. Remarkably, the green peach aphid, Myzus persicae, colonises plant species across 40 families and single M. persicae clonal lineages can colonise distantly related plants. This remarkable ability makes M. persicae a highly destructive pest of many important crop species.Results To investigate the exceptional phenotypic plasticity of M. persicae, we sequenced the M. persicae genome and assessed how one clonal lineage responds to host plant species of different families. We show that genetically identical individuals are able to colonise distantly related host species through the differential regulation of genes belonging to aphid-expanded gene families. Multigene clusters collectively up-regulate in single aphids within two days upon host switch. Furthermore, we demonstrate the functional significance of this rapid transcriptional change using RNA interference (RNAi)-mediated knock-down of genes belonging to the cathepsin B gene family. Knock-down of cathepsin B genes reduced aphid fitness, but only on the host that induced up-regulation of these genes.Conclusions Previous research has focused on the role of genetic adaptation of parasites to their hosts. Here we show that the generalist aphid pest M. persicae is able to colonise diverse host plant species in the absence of genetic specialisation. This is achieved through rapid transcriptional plasticity of genes that have duplicated during aphid evolution. ER -