Project description:Eusocial insects have evolved the capacity to generate adults with distinct morphological, reproductive and behavioural phenotypes from the same genome. Recent studies suggest that RNA editing might enhance the diversity of gene products at the post-transcriptional level, particularly to induce functional changes in the nervous system. Using head samples from the leaf-cutting ant Acromyrmex echinatior, we compare RNA editomes across eusocial castes, identifying ca. 11,000 RNA editing sites in gynes, large workers and small workers. Those editing sites map to 800 genes functionally enriched for neurotransmission, circadian rhythm, temperature response, RNA splicing and carboxylic acid biosynthesis. Most A. echinatior editing sites are species specific, but 8M-bM-^@M-^S23% are conserved across ant subfamilies and likely to have been important for the evolution of eusociality in ants. The level of editing varies for the same site between castes, suggesting that RNA editing might be a general mechanism that shapes caste behaviour in ants. Analysis of genome-wide RNA editing in three different female castes of the the leaf-cutting ant Acromyrmex echinatior.
Project description:Eusocial insects have evolved the capacity to generate adults with distinct morphological, reproductive and behavioural phenotypes from the same genome. Recent studies suggest that RNA editing might enhance the diversity of gene products at the post-transcriptional level, particularly to induce functional changes in the nervous system. Using head samples from the leaf-cutting ant Acromyrmex echinatior, we compare RNA editomes across eusocial castes, identifying ca. 11,000 RNA editing sites in gynes, large workers and small workers. Those editing sites map to 800 genes functionally enriched for neurotransmission, circadian rhythm, temperature response, RNA splicing and carboxylic acid biosynthesis. Most A. echinatior editing sites are species specific, but 8–23% are conserved across ant subfamilies and likely to have been important for the evolution of eusociality in ants. The level of editing varies for the same site between castes, suggesting that RNA editing might be a general mechanism that shapes caste behaviour in ants.
Project description:In social insects, workers perform distinct tasks according to the caste they belong to, and workers from different castes differ in their age (nest workers are usually younger than foragers are). The caste shift thus seems inseparable from age, preventing from deciphering the role of labour division and age in regulating individual physiology and ageing rates. We set up an experimental protocol separating age and caste effects by defining four groups of black garden ant (Lasius niger) workers: young foragers (Y.F), old foragers (O.F), young nest workers (Y.NW) and old nest workers (O.NW). Proteomics highlighted differences between individuals according to their age, whereas metabolomics revealed caste-related differences. Our study highlighted that age and caste influence specifically different aspects of the physiology of ant workers.
Project description:Leaf-cutting ants of the genera Acromyrmex and Atta live in mutualistic symbiosis with a basidiomycete fungus (Leucocoprinus gongylophorus), which they cultivate as fungal gardens in underground nest chambers. The ants provide the fungus with a growth substrate consisting of freshly cut leaf fragments. After new leaf fragments are brought into the nest, the ants chew them into smaller pieces and apply droplets of fecal fluid to the leaf pulp before depositing this mixed substrate in the fungus garden and inoculating it with small tufts of mycelium from older parts of the garden. Previous work has shown that the fecal fluid contains a range of digestive enzymes including proteases, amylases, chitinases, cellulases, pectinases, hemicellulases and laccases, and that most of these enzymes are produced by the fungal symbiont in specialized structures called gongylidia that the ants eat. After ingestion, the enzymes apparently pass unharmed through the alimentary channel of the ants and end up in the fecal fluid. Most likely this complex system is an adaptation of the ant-fungus symbiosis to a herbivorous lifestyle, as the ancient ancestors of the ants and the fungus lived as hunter-gatherers and saprotrophs, respectively. The promise of fecal fluid for getting insight into the molecular adaptations that enables the ant-fungus holosymbiont to live as a herbivore, led us to investigate the fecal fluid proteome using LC-MS/MS in order to get a more comprehensive picture of the repertoire of proteins present.
Project description:We generated snRNA-Seq for olfactory sensory neurons from late stage pupae of the clonal raider ant to study the chemosensory gene expression during development.
Project description:The honeybee (Apis mellifera) is a well-known eusocial insect. In honeybee colonies, thousands of sterile workers, including nurse and forager bees, perform various tasks within or outside the hive, respectively. The queen is the only fertile female and is responsible for reproduction. The queen and workers share similar genomes, but occupy different caste statuses. We established single-cell transcriptomic atlases of brains from queens and worker subcastes, and identified five major cell groups: Kenyon, optic lobe, olfactory projection, glial, and hemocyte cells. By dividing Kenyon and glial cells into multiple subtypes based on credible markers, we observed that vitellogenin (vg) was highly expressed in specific glial-cell subtypes in brains of queens. Knockdown of vg at the early larval stage significantly suppressed the development into adult queens. We demonstrate vg expression as a "molecular signature" for the queen caste, and suggest involvement of vg in regulating caste differentiation.