Epigenetics, embryogenesis and plasticity in insects.
Lead Research Organisation:
University of Leeds
Department Name: Sch of Biology
Abstract
Background
DNA methylation is key for embryonic development in mammals but has not been examined in invertebrates. DNA methylation controls whether honeybee larvae develop into queens or workers. These two distinct castes are derived from the same genome in response to the environment, a phenomenon known as phenotypic plasticity.
Pea aphids also exhibit plasticity; in summer aphids reproduce asexually, but as winter approaches females detect this and alter the development of their embryos giving rise to females that reproduce sexually. Preliminary data indicates that DNA methylation is important for the specification of these cells.
Objectives:
-What role does DNA methylation have in embryogenesis in the pea aphid and honeybee?
-What role does DNA methylation have in developmental plasticity in the pea aphid.
Novelty:
The role of DNA methylation in insect development is unknown; preliminary data indicates that DNA methylation is important for specification of the germ cells. These cells are important for plasticity in the pea aphid. The long-term manipulation of this switch may be key to control of this agricultural pest.
Timeliness:
This project is building on recent data from the Duncan lab and the technology for determining the role of DNA methylation in insects is now available (e.g. live imaging, CRISPR/Cas9, sequencing of small samples).
Experimental Approach:
Obj.1:
Dynamics of gene expression of DNA methylation will be determined using in situ hybridisation and RT-qPCR (for genes involved in methylation) and immunohistochemistry.
The function of DNA methylation during embryonic development in the honeybee and pea aphid will be determined using RNAi/azacytidine/CRISPR/Cas9. Phenotypes will be examined using established markers for cell types as well as examining reproduction in the surviving adults.
Obj.2
The dynamics of expression and function of methylation will be determined in the embryos of females that have been exposed to winter vs. summer conditions.
DNA methylation is key for embryonic development in mammals but has not been examined in invertebrates. DNA methylation controls whether honeybee larvae develop into queens or workers. These two distinct castes are derived from the same genome in response to the environment, a phenomenon known as phenotypic plasticity.
Pea aphids also exhibit plasticity; in summer aphids reproduce asexually, but as winter approaches females detect this and alter the development of their embryos giving rise to females that reproduce sexually. Preliminary data indicates that DNA methylation is important for the specification of these cells.
Objectives:
-What role does DNA methylation have in embryogenesis in the pea aphid and honeybee?
-What role does DNA methylation have in developmental plasticity in the pea aphid.
Novelty:
The role of DNA methylation in insect development is unknown; preliminary data indicates that DNA methylation is important for specification of the germ cells. These cells are important for plasticity in the pea aphid. The long-term manipulation of this switch may be key to control of this agricultural pest.
Timeliness:
This project is building on recent data from the Duncan lab and the technology for determining the role of DNA methylation in insects is now available (e.g. live imaging, CRISPR/Cas9, sequencing of small samples).
Experimental Approach:
Obj.1:
Dynamics of gene expression of DNA methylation will be determined using in situ hybridisation and RT-qPCR (for genes involved in methylation) and immunohistochemistry.
The function of DNA methylation during embryonic development in the honeybee and pea aphid will be determined using RNAi/azacytidine/CRISPR/Cas9. Phenotypes will be examined using established markers for cell types as well as examining reproduction in the surviving adults.
Obj.2
The dynamics of expression and function of methylation will be determined in the embryos of females that have been exposed to winter vs. summer conditions.