Project description:Social caste determination in the honey bee is assumed to be determined by the dietary status of the young larvae and translated into physiological and epigenetic changes through nutrient-sensing pathways. We have employed microRNA gene-microarray, and observed that both worker jelly and royal jelly showed dynamic changes in miRNA content during the 4th to 6th day of larval development . Adding specific miRNAs to royal jelly elicited significant changes in queen larval mRNA expression and in morphological characters of the emerging adult queen bee. We propose that miRNAs in the nurse bee secretions constitute an additional element in the regulatory control of caste determination in the honey bee.
Project description:Social caste determination in the honey bee is assumed to be determined by the dietary status of the young larvae and translated into physiological and epigenetic changes through nutrient-sensing pathways. We have employed Illumina/Solexa sequencing to examine the small RNA content in the bee larval food source, and show that worker jelly is enriched in miRNA complexity and abundance relative to royal jelly. The miRNA levels in worker jelly were 7-215 fold higher than in royal jelly, and both jellies showed dynamic changes in miRNA content during the 4th to 6th day of larval development. Adding specific miRNAs to royal jelly elicited significant changes in queen larval mRNA expression and in morphological characters of the emerging adult queen bee. We propose that miRNAs in the nurse bee secretions constitute an additional element in the regulatory control of caste determination in the honey bee.
Project description:Social caste determination in the honey bee is assumed to be determined by the dietary status of the young larvae and translated into physiological and epigenetic changes through nutrient-sensing pathways. We have employed Illumina/Solexa sequencing to examine the small RNA content in the bee larval food source, and show that worker jelly is enriched in miRNA complexity and abundance relative to royal jelly. The miRNA levels in worker jelly were 7-215 fold higher than in royal jelly, and both jellies showed dynamic changes in miRNA content during the 4th to 6th day of larval development. Adding specific miRNAs to royal jelly elicited significant changes in queen larval mRNA expression and in morphological characters of the emerging adult queen bee. We propose that miRNAs in the nurse bee secretions constitute an additional element in the regulatory control of caste determination in the honey bee. We collected worker and royal jelly of the Italian honeybee (ZND No.1, Apis mellifera ligustica) at 73~90 hours (4th-day larvae), 97~114 hours (5th-day larvae), and 121~138 hours (6th-day larvae) after hatching. After total RNA was extractedM-BM- and quantified , relative equal amounts of total RNAs from each of the three sampling days were pooled into respectively worker and royal jelly samples, and the fraction of small RNAs less than 30nt long was retained and sequenced on the Illumina/Solexa high-throughput platform (HTP).
Project description:Social caste determination in the honey bee is assumed to be determined by the dietary status of the young larvae and translated into physiological and epigenetic changes through nutrient-sensing pathways. We have employed microRNA gene-microarray, and observed that both worker jelly and royal jelly showed dynamic changes in miRNA content during the 4th to 6th day of larval development . Adding specific miRNAs to royal jelly elicited significant changes in queen larval mRNA expression and in morphological characters of the emerging adult queen bee. We propose that miRNAs in the nurse bee secretions constitute an additional element in the regulatory control of caste determination in the honey bee. We collected worker and royal jelly of the Italian honeybee (ZND No.1, Apis mellifera ligustica) at 73~90 hours (4th-day larvae), 97~114 hours (5th-day larvae), and 121~138 hours (6th-day larvae) after hatching. After total RNA was extractedM-BM- and quantified , equal amounts of total RNAs from each of the three sampling days were analyzed on the LC Science miRNA-array to observe the expression variation of miRNAs between worker jelly and royal jelly along with the development time points (4th-day, 5th-day and 6th-day).
Project description:The timing and amplitude of reproductive effort are central life history variables for all organisms. In social insects, reproductive effort is collectively controlled at the colony level but little is known about the mechanisms that determine how much colonies invest in reproduction. As part of their female reproductive investment, honey bee colonies raise multiple new queens by feeding royal jelly to female larvae. Artificial selection for commercial royal jelly production in China has generated over the past 40 years a stock of royal jelly bees that raises an order of magnitude more queens and provisions each queen with >3x more royal jelly than unselected stock. Here we establish in a reciprocal cross-fostering experiment that this dramatic shift in social phenotype is due to changes in the nurse bees that care for the brood. We demonstrate higher electrophysiological responsiveness to brood pheromones in royal jelly bees than in unselected bees. Comparing the antennal proteome of unselected and royal jelly bees, we identify proteins involved in chemosensation and energy metabolism as candidates for the observed differences. We confirm several candidates, most prominently OBP16 and CSP4, with quantitative differences of corresponding mRNA levels and functional binding assays between the brood pheromones and the chemosensory proteins. Furthermore, we complement analyses of brood volatiles and electrophysiological recordings with behavioral attraction assays to confirm the presumed biological function of one newly discovered and two existing larval pheromones. Together, these findings help our understanding of pheromonal communication in honey bees and explain how sensory changes in nurse honey bees as alloparental caregivers have evolved in response to artificial selection, leading to a profound shift in colony-level resource allocation to sexual reproduction.
Project description:Transcriptome sequencing has become the main methodology for analyzing the relationship between genes and characteristics of interests, particularly those associated with diseases and economic traits. Because of its functional superiority, commercial royal jelly (RJ) and its production are major areas of focus in the field of apiculture. Multiple lines of evidence have demonstrated that many factors affect RJ output by activating or inhibiting various target genes and signaling pathways to augment their efficient replication. The coding sequences made available by the Honey Bee Genome Sequencing Consortium have permitted a pathway-based approach for investigating the development of the hypopharyngeal glands (HGs). In the present study, 3573941, 3562730, 3551541, 3524453, and 3615558 clean reads were obtained from the HGs of five full-sister honey bee samples using Solexa RNA sequencing technology. These reads were then assembled into 18378, 17785, 17065, 17105, and 17995 unigenes, respectively, and aligned to the DFCI Honey Bee Gene Index database. The differentially expressed genes (DEGs) data were also correlated with detailed morphological data for HGs acini. The results identify areas that warrant further study, including those that can be used to improve honey bee breeding techniques and help ensure stable yields of RJ with high quality traits. The 5 samples at given time (d3, d6, d9, d12, d16 after adult worker bees emergence from the comb) are in the critical stage of the RJ secretion and HGs developments indicated (triggered) the further caste differentiation (worker bees and queen) and task switch (nurse bees and foragers). 30 pooled heads of each samples were
Project description:Honey bee drones, queens and workers have vastly different phenotypes. Here we profile the the expression level of mRNAs and microRNAs of honeybee, drones, queens and workers at the L5 larval stage (91 hours +/- 1).
Project description:The genome of the western honey bee (Apis mellifera) harbours ten different major royal jelly protein genes (mrjp1-10) which originate from a single-copy precursor via gene duplication. The evolutionary fate of duplicated genes is eventually determined over time as to result in loss due to pseudogenization, or in preservation due to neo- or sub-functionalization. Both fates were already observed in the mrjp gene cluster, as only mrjp1 - 9 are expressed, whereas mrjp10 was pseudogenized and represents an incomplete gene copy. In contrast, MRJP1 underwent neofunctionalization and developed an essential function within the food jelly of queen larvae, to guaranty the survival of the whole colony. We here show combining quantitative real time PCR with quantitative mass spectrometry that expression of most mrjps (mrjp1-5 and 7) shows an age dependent pattern in worker hypopharyngeal glands as well as in brains. Expression increases after hatching until the nurse bee period and is followed by a decrease in older workers that forage for different plant products. Mrjp6 expression deviates considerably from the expression profiles of the other mrjps and transcript abundance does not correlate with protein amount. Thus, either mrjp6 does fulfil a total different function or it might be on its way to pseudogenization. Furthermore, a tissue-specific function of the proteins MRJP8 and 9 in the hypopharyngeal glands and the brain can be excluded, suggesting a more general physiological than a nutritive function for both gene products.
Project description:The present study is the first study to identify the involvement of mRNA, lncRNAs, circRNAs and miRNA in the ovary of honey-bee workers.We predicted 10271 mRNAs, 7235 lncRNAs, 11794 circRNAs and 164 miRNAs in the ovary of honey bee workers.