|WHEELER, DIANA - University Of Arizona|
|BUCK, NORMAN - University Of Arizona|
Submitted to: Insect Molecular Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/22/2014
Publication Date: 10/1/2014
Citation: Wheeler, D.E., Buck, N.A., Evans, J.D. 2014. Expression of insulin/insulin-like signaling and TOR pathway genes in honey bee caste determination. Insect Molecular Biology. 23(1):113-121.
Interpretive Summary: Honey bee queens develop from female larvae that receive an especially rich food source. Determining how this resource is converted into healthy queens can provide insights into both queen health and honey bee nitrition. By focusing on two genetic routes known from animals generally, we were able to show at which point female larvae are flexible or inflexible to changes in diet, and we can predict more generally how bees respond to changes in their nutrition. These results have importance for understanding nutrition maintenance, healthy queens and the abilities of bees to survive stress from parasites and pathogens.
Technical Abstract: Honeybees have two types of adults, queens and workers, that are morphologically distinct. During development, honey bee larvae can develop into either queens or workers, depending on the quality of the food they receive. Growth and nutrition are linked by the evolutionarily conserved insulin/insulin-like signaling (IIS) and TOR pathways. The IIS pathway is sensitive to circulating levels of glucose via insulin secretion and TOR is the main mediator of amino acid sensing. We monitored gene expression of selected genes for components of the IIS and TOR pathways in bee larvae from 40 – 88 hours post hatching. In addition to following normal queen and worker development, we generated individuals with more complex nutritional experiences by switching larvae from one diet type to the other. Our goal was to determine differences between queen and worker larvae as well as their responses to nutritional shifts. We found that responses of honeybees showed intriguing differences in comparison to the insect ground plan, as represented by Drosophila melanogaster.