Developmental transitions in some parasitic angiosperms are tied directly to host-derived chemical cues (xenognosins). The obligate hemi-parasite Striga asiatica, initiates the root apical meristem population (germina...Developmental transitions in some parasitic angiosperms are tied directly to host-derived chemical cues (xenognosins). The obligate hemi-parasite Striga asiatica, initiates the root apical meristem population (germination), development of the host attachment organ (the haustorium), and shoot apical meristem initiation (seed coat shedding) in response to specific xengonosins. These checkpoints synchronize spatial and temporal tissue development. We have now exploited the external control over these developmental transitions to trace functional expression in haustorial organogenesis. Genes associated with phytohormone regulation, metabolism, vascular tissue development, and reactive oxygen species (ROS) production identified in this study suggest an elaborate and global response closely tied to plant defense and redox chemistry that may also be components of a more general quorum sensing-type mechanism in plants.展开更多
Baylisascaris schroederi,a roundworm(ascaridoid)parasite specific to the bamboofeeding giant panda(Ailuropoda melanoleuca),represents a leading cause of mortality in wild giant panda populations.Here,we present a 293-...Baylisascaris schroederi,a roundworm(ascaridoid)parasite specific to the bamboofeeding giant panda(Ailuropoda melanoleuca),represents a leading cause of mortality in wild giant panda populations.Here,we present a 293-megabase chromosome-level genome assembly of B.schroederi to infer its biology,including host adaptations.Comparative genomics revealed an evolutionary trajectory accompanied by host-shift events in ascaridoid parasite lineages after host separations,suggesting their potential for transmission and rapid adaptation to new hosts.Genomic and anatomical lines of evidence,including expansion and positive selection of genes related to the cuticle and basal metabolisms,indicate that B.schroederi undergoes specific adaptations to survive in the sharp-edged bamboo-enriched gut of giant pandas by structurally increasing its cuticle thickness and efficiently utilizing host nutrients through gut parasitism.Additionally,we characterized the secretome of B.schroederi and predicted potential drug and vaccine targets for new control strategies.Overall,this genome resource provides new insights into the host adaptation of B.schroederi to the giant panda as well as the host-shift events in ascaridoid parasite lineages.Our findings on the unique biology of B.schroederi will also aid in the development of prevention and treatment measures to protect giant panda populations from roundworm parasitism.展开更多
文摘Developmental transitions in some parasitic angiosperms are tied directly to host-derived chemical cues (xenognosins). The obligate hemi-parasite Striga asiatica, initiates the root apical meristem population (germination), development of the host attachment organ (the haustorium), and shoot apical meristem initiation (seed coat shedding) in response to specific xengonosins. These checkpoints synchronize spatial and temporal tissue development. We have now exploited the external control over these developmental transitions to trace functional expression in haustorial organogenesis. Genes associated with phytohormone regulation, metabolism, vascular tissue development, and reactive oxygen species (ROS) production identified in this study suggest an elaborate and global response closely tied to plant defense and redox chemistry that may also be components of a more general quorum sensing-type mechanism in plants.
基金supported by the Chengdu Giant Panda Breeding Research Foundation,China(Grant No.CPF-2012-13)the Self-supporting Project of Chengdu Giant Panda Breeding Research Base,China(Grant No.2020CPBB20)+2 种基金the Sichuan International Science and Technology Innovation Cooperation/Hong Kong,Macao,and Taiwan Science and Technology Innovation Cooperation Project,China(Grant No.2019YFH0065)the National Natural Science Foundation of China(Grant No.31801048)the Highlevel Scientific Research Foundation for the Introduction of Talents of Sichuan Agricultural University of China(Grant No.03120322).
文摘Baylisascaris schroederi,a roundworm(ascaridoid)parasite specific to the bamboofeeding giant panda(Ailuropoda melanoleuca),represents a leading cause of mortality in wild giant panda populations.Here,we present a 293-megabase chromosome-level genome assembly of B.schroederi to infer its biology,including host adaptations.Comparative genomics revealed an evolutionary trajectory accompanied by host-shift events in ascaridoid parasite lineages after host separations,suggesting their potential for transmission and rapid adaptation to new hosts.Genomic and anatomical lines of evidence,including expansion and positive selection of genes related to the cuticle and basal metabolisms,indicate that B.schroederi undergoes specific adaptations to survive in the sharp-edged bamboo-enriched gut of giant pandas by structurally increasing its cuticle thickness and efficiently utilizing host nutrients through gut parasitism.Additionally,we characterized the secretome of B.schroederi and predicted potential drug and vaccine targets for new control strategies.Overall,this genome resource provides new insights into the host adaptation of B.schroederi to the giant panda as well as the host-shift events in ascaridoid parasite lineages.Our findings on the unique biology of B.schroederi will also aid in the development of prevention and treatment measures to protect giant panda populations from roundworm parasitism.
