Project description:The evolution of eukaryotic organisms is often strongly influenced by microbial symbionts that confer novel traits to their hosts. Here we describe the intracellular Enterobacteriaceae symbiont of the invasive ant Cardiocondyla obscurior, 'Candidatus Westeberhardia cardiocondylae'. Upon metamorphosis, Westeberhardia is found in gut-associated bacteriomes that deteriorate following eclosion. Only queens maintain Westeberhardia in the ovarian nurse cells from where the symbionts are transmitted to late-stage oocytes during nurse cell depletion. Functional analyses of the streamlined genome of Westeberhardia (533?kb, 23.41% GC content) indicate that neither vitamins nor essential amino acids are provided for the host. However, the genome encodes for an almost complete shikimate pathway leading to 4-hydroxyphenylpyruvate, which could be converted into tyrosine by the host. Taken together with increasing titers of Westeberhardia during pupal stage, this suggests a contribution of Westeberhardia to cuticle formation. Despite a widespread occurrence of Westeberhardia across host populations, one ant lineage was found to be naturally symbiont-free, pointing to the loss of an otherwise prevalent endosymbiont. This study yields insights into a novel intracellular mutualist that could play a role in the invasive success of C. obscurior.

| S-EPMC4737929 | biostudies-literature

How can ant queens live so long? Genes of multiple longevity pathways change expression with age in the ant Temnothorax rugatulus

Project description:Senescence is manifested by an increase in oxidative stress and a decline in biological functions with age. In most organisms, body maintenance is traded-off with reproduction. The negative relationship between longevity and fecundity is also evident on the molecular level, yet the proximate mechanisms remain poorly understood. Apparently by-passing this trade-off, social insect queens are both extremely long-lived (up to 30 years in some ants) and highly fecund compared to workers. Here, we study changes in gene expression with age and fecundity in queens to determine how the trade-off between those two traits is reshaped. We analyse tissue-specific gene expression in young founding queens and old, highly fecund queens of the ant Temnothorax rugatulus. More genes altered their expression with age in the fat body than in the brain. Despite strong differences in ovary development, few fecundity genes were differentially expressed. However, many longevity genes involved in well-known pathways or lifespan-associated biological processes changed their expression with age indicating that multiple longevity mechanisms are activated successively throughout a queens’ life. Young queens invested in immunity (i.e. activation of the Toll signalling pathway) and resistance against environmental and physiological stress associated with the founding phase (i.e. down regulation of the TOR pathway), while established older queens up-regulate anti-aging mechanisms (i.e. up-regulation of catalase, superoxide dismutase, heat shock 70 kDa proteins). Finally, we identified a number of candidate genes and pathways, potentially involved in reshaping the fertility-longevity trade-off in social insects, shedding light on how this is achieved on a proximate level.

2018-03-06 | GSE111415 | GEO

Genomics of colony founding in fire ants - pleo1

Project description:Fire ant queens were collected immediately after a nuptial mating flight and split into two groups: paired queens (pleometrosis) and individual queens(haplometrosis). All the queens were provided with a nesting chamber consisting of a glass tube half-filled with water, which was covered by a cotton ball and a layer of dental plaster. Tubes were sealed with a loose cap to provide air flow. Specimens were reared in the dark at 28C, 70% relative humidity under claustral conditions (no food and no water) for 1 month. After the eclosion of the first batch of workers (minims), incipient colonies were provided with water, sugar water and frozen crickets. Glass tubes were set open in pencil boxes coated with Fluon to prevent escape. Queens were subsequently monitored daily until it was possible to identify the social rank of the two cofoundresses in pleometrotic couples.

2013-08-21 | E-MEXP-3886 | biostudies-arrayexpress

Cardiocondyla obscurior

Project description:Cardiocondyla obscurior Raw sequence reads

| PRJNA384518 | ENA

Cardiocondyla obscurior

Project description:Cardiocondyla obscurior overview

| PRJNA269085 | ENA

Cardiocondyla obscurior

Project description:Cardiocondyla obscurior Raw sequence reads

| PRJNA819887 | ENA