Decoupling the effects of nutrition, age and behavioral caste on honey bee physiology and immunity

Miguel Corona; Belen Branchiccela; Shayne Madella; Yanping Chen; Jay Evans

The copyright holder for this preprint (which was not peer-reviewed) is the author/funder. . https://doi.org/10.1101/667931 doi: bioRxiv preprint 530 Mrjp1 expression patterns revealed several interesting insights. First, we found highly significant 531 differences between nurses and foragers independently of nutritional condition and age. 532 Nurse/forager expression differences were especially large in younger 2-week old workers. This 533 expression pattern unveils mrjp1 as a reliable biomarker of behavior for whole body analyses. 534 Second, young nurses from pollen-restricted colonies had lower mrjp1 levels compared with 535 pollen-unrestricted colonies (P=0.02), but no significant differences between nutritional groups 536 were found in older nurses. Thus, in contrast with vg, the effect of pollen restriction was limited 537 to younger nurses. Third, foragers showed intriguing changes of mrjp1 expression associated with 538 nutrition and age. Younger 2-week-old foragers from colonies with high pollen storages (P-UR), 539 have higher mrjp1 levels compared with foragers from colonies with low pollen storage (P-R). 549 Still, these results suggest interesting possibilities for future studies. Royal jelly proteins secretion 550 from nurses' hypopharyngeal glands has been primarily associated with larval and queen feeding. 551 However, these proteins also are transferred during trophallaxis -mouth to mouth food transfer -552 preferentially to younger workers [86, 87] . Consistently, our results suggest that foragers could be 553 MRJPs donors during trophallactic interactions and that the potential for these interactions 554 increases with nutrition and age. Interestingly, it has been hypothesized that the transfer of royal This article is a US Government work. It is not subject to copyright under 17 USC 105 and is also made available for use under a CC0 license.