Biology subjects

Shpigler, H. Y.

Publications and source records attributed to Shpigler, H. Y..

3 recordsLinked to original sources

bioRxiv2024

The Social and Nutritional Factors Controlling the Growth of Honey Bee (Apis mellifera) Queens

The honey bee queen is essential for colony function, laying thousands of eggs daily and determining the colonys genetic composition. Beekeepers cultivate and trade queens to enhance colony health and productivity. Despite its significance, artificial queen rearing in foster queenless colonies has remained largely unchanged for over a century, offering limited control over the environmental conditions influencing larval development. In this study, we developed a laboratory-based method for queen bee rearing, establishing a protocol for rearing queens in cages in the lab under controlled environmental conditions. We first investigated the minimal number of worker bees required to rear a single queen and found that groups of 200 workers raise queens with comparable success and weight to those reared in colonies. As a proof of concept, we examined the impact of larval age on rearing success in our new system. We found that the age of the larvae affects the success rate of queen development and that younger larvae developed into heavier queens than older larvae, as published in the past using the traditional queen-rearing method. Additionally, we assessed the influence of pollen nutrition on queen-rearing success, finding that a high pollen concentration is crucial for queen development. These findings and the new method provide a foundation for studying queen bee development in a controlled environment and offer potential applications for improving queen-rearing practices.

zoology↗

bioRxiv2020

The evolution of extreme fertility defied ancestral gonadotropin mediated brain-reproduction tradeoff

Gonadotropic hormones coordinate processes in diverse tissues regulating animal reproductive physiology and behavior. Juvenile hormone (JH) is the ancient and most common gonadotropin in insects, but not in advanced eusocial honey bees and ants. To probe the evolutionary basis of this change, we combined endocrine manipulations, transcriptomics, and behavioral analyses to study JH regulated processes in a bumble bee showing an intermediate level of sociliality. We found that in the fat body, more JH-regulated genes were upregulated and enriched for metabolic and biosynthetic pathways. This transcriptomic pattern is consistent with earlier evidence that JH is the major gonadotropin in the bumble bee. In the brain, most JH-regulated genes were downregulated and enriched for protein turnover pathways. Brain ribosomal protein gene expression was similarly downregulated in dominant workers, which naturally have high JH titers. In other species, similar downregulation of protein turnover is found in aging brains or under stress, and is associated with compromised long-term memory and health. These findings suggest a previously unknown gonadotropin-mediated tradeoff. We did not find a similar downregulation of protein turnover pathways in the brain of honey bees in which JH is not a gonadotropin but rather regulates division of labor. These differences between JH effets in the bumble bee and in the advanced eusocial honey bee suggest that the evolution of advanced eusociality was associated with modifications in hormonal signaling supporting extended and extremely high fertility while reducing the ancient costs of high gonadotropin titers to the brain.

evolutionary biology↗

bioRxiv2017

Cross-species systems analyses reveal a conserved brain transcriptional response to social challenge

Social challenges like territorial intrusions evoke behavioral responses in widely diverging species. Recent work has revealed that evolutionary \"toolkits\" - genes and modules with lineage-specific variations but deep conservation of function - participate in the behavioral response to social challenge. Here, we develop a multi-species computational-experimental approach to characterize such a toolkit at a systems level. Brain transcriptomic responses to social challenge was probed via RNA-seq profiling in three diverged species - honey bees, mice, and three-spined stickleback fish - following a common methodology, allowing fair comparisons across species. Data were collected from multiple brain regions and multiple time points after social challenge exposure, achieving anatomical and temporal resolution substantially greater than previous work. We developed statistically rigorous analyses equipped to find homologous functional groups among these species at the levels of individual genes, functional and coexpressed gene modules, and transcription factor sub-networks. We identified six orthogroups involved in response to social challenge, including groups represented by mouse genes Npas4 and Nr4a1, as well as common modulation of systems such as transcriptional regulators, ion channels, G-protein coupled receptors, and synaptic proteins. We also identified conserved coexpression modules enriched for mitochondrial fatty acid metabolism and heat shock that constitute the shared neurogenomic response. Our analysis suggests a toolkit wherein nuclear receptors, interacting with chaperones, induce transcriptional changes in mitochondrial activity, neural cytoarchitecture, and synaptic transmission after social challenge. It reveals systems-level mechanisms that have been repeatedly co-opted during evolution of analogous behaviors, thus advancing the genetic toolkit concept beyond individual genes.

genomics↗