The physiological and social behaviors differ widely between honeybee workers and drones. All the organ rudiments of adult bees are formed during the embryonic stage. The initial molecular bases at the proteomic level for both embryonic developments have been identified, but a comprehensive understanding of the significant events involved in embryonic establishment remains elusive. To elucidate the molecular regulatory mechanisms underlying tissue differentiation during the embryogenesis of drones and workers, we implemented a state-of-the-art approach that combines in-hive inspection and targeted sampling (at nine embryogenesis stages) with high-throughput proteomics technology to investigate the developmental differences. In-hive inspection of hatching timing revealed an average developmental gap of approximately 3.6 h between the two embryos. Furthermore, proteomic analyses indicate that drone and worker embryos adopt distinct developmental strategies. Notably, proteins involved in fatty acid metabolism and key biological pathways related to organ formation-such as the Hedgehog and Wnt signaling pathways-are activated earlier in drones, suggesting that tissue development begins sooner in drone embryos than in workers. Additionally, the upregulation of cytoskeletal proteins and antioxidants in drone embryos likely supports their larger cell size and higher metabolic stress, reflecting distinct molecular characteristics of male development. Ribosomal proteins essential for biosynthetic support remain consistently expressed throughout the late stages in male embryos, indicating that drone embryogenesis lasts longer than that of workers. This work provides novel insights into the molecular foundations of honeybee embryogenesis and lays both theoretical and practical groundwork for future research into the mechanisms driving embryonic development.

Nest architecture in social insects is often viewed as a static structural component providing shelter or storage1. However, the extent to which these constructed environments actively shape biological traits remains poorly understood. Although the genetic and nutritional drivers of honey bee caste determination are well established2-4, the role for specialized queen cells has largely been attributed to spatial or structural factors, overlooking the influence of the physicochemical microenvironment5. Here we show that worker construction behaviour actively engineers a physicochemical niche that is crucial for queen development in honey bees. Queen cells exhibit distinct mechanical and chemical signatures that differ markedly from those of worker cells. These properties are not an accidental by-product of worker cell construction: workers construct queen cells deliberately and, in doing so, undergo task-specific physiological and transcriptomic reprogramming that enables precise engineering of these cell properties. Experimental manipulations of the rearing environment demonstrate that these physicochemical cues are causally required for normal queen development, functioning as a critical checkpoint that can profoundly influence an individual larva's development. Together, our results establish a direct mechanistic link between social construction behaviour and developmental plasticity, revealing how an engineered environment can channel organismal fate.

Honeybees require diverse nutrients for larval growth, adult development, and colony health. Pollen quality significantly impacts reproduction, productivity, and growth. Bioactive substances from honeybee glands enhance colony health, with recent studies showing that optimal citric acid intake extends lifespan, boosts pollen consumption, accelerates mandibular gland development, and improves royal jelly quality. This review examines organic acid feeding’s effects on gland development and overall health, offering insights for beekeeping and supplementary food development to support sustainable apiculture. Research gaps in organic acid supplementation, gland development, and health benefits are identified. The impact of varying organic acid concentrations on 10-HDA biosynthesis in mandibular glands and key regulatory proteins influencing 10-HDA expression is summarized. Findings highlight the benefits of organic acid supplements for worker bee gland development and health, guiding future research and practical applications in beekeeping.

High royal jelly production is an adaptive reproductive investment syndrome in honey bees that enhances their nursing ability to queen bee larvae. However, the biological basis of this reproduction investment at the multi-organ level remains elusive. In this study, proteome across 11 organs of two bee stocks: high royal jelly production bees (RJBs) and Italian bees (ITBs) was compared. Our analysis revealed significant differences in protein expression profiles in brain, fat body, mandibular gland, and Malpighian tubule, highlighting their crucial roles in regulating royal jelly secretion in RJBs. The increased energy turnover, protein synthesis, and lipid synthesis observed in RJBs compared to ITBs highlight their enhanced metabolic activity, which is essential for the robust secretion of royal jelly in RJBs. The elevated abundance of major royal jelly proteins (MRJPs), hexamerins, and vitellogenin suggests their critical contributions to the nutritional and material requirement necessary for royal jelly secretion. Furthermore, the high level of vitellogenin and juvenile hormone esterase may suppress juvenile hormones, which contribute to a strong royal jelly secretion and sensitivity of RJBs to larval pheromones relative to ITBs. This comprehensive dataset contributes to a better understanding of nursing behavior and reproductive investment in honey bees. Significiance. The royal jelly secretion syndrome is a colony level social trait dominated by the intricate interplay of multiple organs. However, previous studies have primarily focused on individual organs. In this study, the proteome of 11 organs was compared between high royal jelly production bees (RJBs) and Italian bees (ITBs) to provide knowledge on how multiple organs cooperate to boost the elevated royal jelly production by RJBs. Nutrition supply was sufficient at multiple organs of RJBs when compared to ITBs, indicating that nutrition plays an essential role in boosting energy metabolism, protein and lipid synthesis, and directly contributes to the amount of royal jelly secretion. The high level of secretion of storage proteins, such as MRJPs, hex, and vitellogenin, provides sufficient nutrition and material for royal jelly secretion. Moreover, the higher levels of vitellogenin and juvenile hormone esterase may suppress juvenile hormone synthesis, and contributing to stronger sense of RJBs to larval pheromone relative to ITBs. This suggests that nutrition can influence the hormone levels and sensory abilities of RJBs nurse bees to promote their royal jelly secretion ability. The reported data provide insights into the systematic regulation strategy of honeybee nursing behavior and reproductive investment.

Wax gland complex (WGC) serves as the primary generator of beeswax; however, the dynamic biological function in wax secretion remains unclear. To elucidate the developmental mechanism of WGC, we conducted a comprehensive analysis to reveal the variations in proteins and metabolites among the newly emerged bee (NEB), wax-secreting bee (WSB), and overaged bee (OAB). We identified 3,295 proteins and 159 metabolites in WGC. Specifically, NEB elevated the expression of ribosomal proteins for preparing the glandular organ. While WSB promoted the size of epidermal cells and oenocytes, the enrichment of fatty acids and energy metabolism in WSB suggested a strong ability in wax synthesis. In OAB, disorganized wax tubules, and up-regulated cysteine proteases reflected the gland degeneration. These findings highlight the dynamic changes in the level of molecule and morphological structure in WGC, offering valuable insights into the development and mechanism of wax secretion in honeybees and other wax insects.

Age-based division of labor among workers is a fundamental life-history trait of many social insects, including the Western honey bee, Apis mellifera L. Extensive studies of the causation of the most pronounced transition from performing tasks in the nest to outside foraging indicate hormonal regulation of complex physiological changes. However, the proximate neurobiological mechanisms that cause the behavioral repertoire to change are still not understood and require novel approaches to be fully characterized. Thus, we established the first comprehensive monoclonal antibody microarray in honey bees with 16,320 antibodies to directly identify proteins in the brain that regulate the transition to foraging. Major royal jelly protein (MRJP) 1 and MRJP3 were identified as potential protein effectors and further investigated. A series of experimental manipulations of the workers' behavioral transition led to changes in MRJP1 and MRJP3 quantities in accordance with their presumed functional role. Injection of MRJPs into the brain resulted in increased task-reversal from foraging to nursing and decreased task-progression from nursing to foraging, while the latter was increased by injection with MRJP antibodies. Finally, down-regulation of MRJP1 and MRJP3 expression via RNAi injection into the brain increased the transition from in-hive nursing to outside foraging, confirming a causal role of these two proteins in the proximate regulation of behavior and life-history of honey bee workers. Interaction partners of MRJP1 and MRJP3 in the honey bee brain included other regulators of honey bee behavior and life history. Thus, our transformative methodological advancement of proteome analysis in honey bees reveals novel regulators of honey bee behavior, extends our understanding of the functional pleiotropy of MRJPs, and supports a general nutrition-based model of the regulation of the age-based division of labor in honey bees.

[目的]探究蜂王浆中含量最高的活性分子——蜂王浆主蛋白1(MRJP1)基因敲入血管平滑肌细胞后,在体内水平上是否具有调节小鼠血压的功能.[方法]利用CRISPR/Cas9技术,将可识别小鼠Hipp11位点的gRNA、Cas9和包含Sm22a启动子+Mrjp1 cDNA的载体共显微注射小鼠受精卵,制备在血管平滑肌细胞中特异性表达的Mrjp1基因定点敲人小鼠,并验证敲人位点的正确性.小鼠背部皮下包埋微渗透压缓释泵,持续将血管紧张素Ⅱ(AngⅡ)诱导野生型(WT)和纯合子(Mrjp1+/+)小鼠,比较不同时间收缩压和舒张压,以及胸主动脉中膜面积/管腔面积(Media/Lumen area)比值的差异.[结果]F0代嵌合体小鼠与野生型交配,产生杂合子(Mrjp1+/-)小鼠,对Mrjp1+/-小鼠敲人位点同源重组片段的PCR扩增、测序和Southern blotting检测结果显示,Mrjp1基因成功整合到小鼠染色体Hipp11位点.Mrjp1+/-小鼠之间交配产生WT、Mrjp1+/-和Mrjp1+/+小鼠,Mrjp1基因在胸主动脉中能够顺利转录和翻译.持续给予AngⅡ,Mrjp1+/+小鼠收缩压和舒张压升高趋势整体低于WT小鼠,收缩压在第3、6、9、12天差异显著(P＜0.05),舒张压在第3(P＜0.05)、6(P＜0.01)天差异显著;经AngⅡ刺激后,Mrjp1+/+小鼠胸主动脉Media/Lumen area比值亦显著低于WT小鼠(P＜0.05).[结论]Mrjp1基因特异性敲人小鼠血管平滑肌细胞,可在体内水平上抑制AngⅡ诱导的高血压,为深入了解MRJP1蛋白功能及精准开发蜂王浆提供了重要的理论依据.

Camellia bee pollen (CBP) is a major kind of bee product which is collected by honeybees from tea tree (Camellia sinensis L.) flowers and agglutinated into pellets via oral secretion. Due to its special healthcare value, the authenticity of its botanical origin is of great interest. This study aimed at distinguishing CBP from other bee pollen, including rose, apricot, lotus, rape, and wuweizi bee pollen, based on a non-targeted metabolomics approach using ultra-high performance liquid chromatography–mass spectrometry. Among the bee pollen groups, 54 differential compounds were identified, including flavonol glycosides and flavone glycosides, catechins, amino acids, and organic acids. A clear separation between CBP and all other samples was observed in the score plots of the principal component analysis, indicating distinctive metabolic profiles of CBP. Notably, L-theanine (864.83–2204.26 mg/kg) and epicatechin gallate (94.08–401.82 mg/kg) were identified exclusively in all CBP and were proposed as marker compounds of CBP. Our study unravels the distinctive metabolic profiles of CBP and provides specific and quantified metabolite indicators for the assessment of authentic CBP.

Protein phosphorylation is known to regulate a comprehensive scenario of critical cellular processes. However, phosphorylation-mediated regulatory networks in honey bee embryogenesis are mainly unknown. We identified 6342 phosphosites from 2438 phosphoproteins and predicted 168 kinases in the honey bee embryo. Generally, the worker and drone develop similar phosphoproteome architectures and major phosphorylation events during embryogenesis. In 24 h embryos, protein kinases A play vital roles in regulating cell proliferation and blastoderm formation. At 48–72 h, kinase subfamily dual-specificity tyrosine-regulated kinase, cyclin-dependent kinase (CDK), and induced pathways related to protein synthesis and morphogenesis suggest the centrality to enhance the germ layer development, organogenesis, and dorsal closure. Notably, workers and drones formulated distinct phosphoproteome signatures. For 24 h embryos, the highly phosphorylated serine/threonine-protein kinase minibrain, microtubule-associated serine/threonine-protein kinase 2 (MAST2), and phosphorylation of mitogen-activated protein kinase 3 (MAPK3) at Thr564 in workers, are likely to regulate the late onset of cell proliferation; in contrast, drone embryos enhanced the expression of CDK12, MAPK3, and MAST2 to promote the massive synthesis of proteins and cytoskeleton. In 48 h, the induced serine/threonine-protein kinase and CDK12 in worker embryos signify their roles in the construction of embryonic tissues and organs; however, the highly activated kinases CDK1, raf homolog serine/threonine-protein kinase, and MAST2 in drone embryos may drive the large-scale establishment of tissues and organs. In 72 h, the activated pathways and kinases associated with cell growth and tissue differentiation in worker embryos may promote the configuration of rudimentary organs. However, kinases implicated in cytoskeleton organization in drone embryos may drive the blastokinesis and dorsal closure. Our hitherto most comprehensive phosphoproteome offers a valuable resource for signaling research on phosphorylation dynamics in honey bee embryos.

Egg size plasticity represents an adaptive reproductive strategy in numerous organisms, including the honey bee, Apis mellifera . However, the proximate causation of this plasticity and egg size in general is unknown. We show that honey bee queens predictably and reversibly adjust egg size in response to their colony size and that this plasticity is an active response to the queens’ perception of colony size instead of a consequence of egg laying rate. The egg size increase involves changes of 290 ovarian proteins, mostly related to increased energy metabolism, protein transport, and cytoskeleton functions. Spatio-temporal expression analysis of the small GTPase Rho1 indicates its central role in egg size regulation, which we confirm by RNAi-mediated gene knock-down and expression analyses. The molecular adjustments that promote maternal investment of honey bee queens in response to their social environment thus reveal a novel mechanism of egg size regulation.

10-Hydroxydec-2-enoic acid (10-HDA), an unsaturated hydroxyl fatty acid from the natural food royal jelly, can protect against cell and tissue damage, yet the underlying mechanisms are still unexplored. We hypothesized that the neutralization of the hydroxyl free radical (•OH), the most reactive oxygen species, is an important factor underlying the cytoprotective effect of 10-HDA. In this study, we found that the •OH scavenging rate by 10-HDA (2%, g/ml) was more than 20%, which was achieved through multiple-step oxidization of the –OH group and C=C bond of 10-HDA. Moreover, 10-HDA significantly enhanced the viability of vascular smooth muscle cells (VSMCs) damaged by •OH (P < 0.01), significantly attenuated •OH-derived malondialdehyde production that represents cellular lipid peroxidation (P < 0.05), and significantly increased the glutathione levels in •OH-stressed VSMCs (P < 0.05), indicating the role of 10-HDA in reducing •OH-induced cytotoxicity. Further proteomic analyses of VSMCs identified 195 proteins with decreased expression by •OH challenge that were upregulated by 10-HDA rescue and were primarily involved in protein synthesis (such as translation, protein transport, ribosome, and RNA binding) and energy metabolism (such as fatty acid degradation and glycolysis/gluconeogenesis). Taken together, these findings indicate that 10-HDA can effectively promote cell survival by antagonizing •OH-induced injury in VSMCs. To the best of our knowledge, our results provide the first concrete evidence that 10-HDA-scavenged •OH could be a potential pharmacological application for maintaining vascular health.

【Objective】The objective of this study is to investigate the proteome profile of the postcereberal gland (PGld) and thoracic gland (ThGld) between high royal jelly producing bees (Apis mellifera liguatica, RJBs) and Italian bees (Apis mellifera liguatica, ITBs) with the aim of revealing the molecular basis of salivary gland regulating royal jelly production, and to provide a basis for analyzing the high-yield mechanism of royal jelly.【Method】PGld and ThGld were dissected from nurse bees of RJBs and ITBs. After protein extraction and enzyme digestion, the peptide samples were analyzed by liquid chromatography coupled with tandem mass spectrometry. Furthermore, the mass spectral data were qualified and quantified by MaxQuant software, and the following bioinformatic analysis was conducted using Perseus software, prediction of secretory protein was achieved by SignalP database, biological process and KEGG pathway were enriched by Cluego software.【Result】Totally 2 335 proteins were identified in salivary glands of RJBs and ITBs nurse bees, including 1 823 proteins in PGld and 1 922 proteins in ThGld. The expression profiles of the core proteins in the PGld and ThGld of RJBs and ITBs were similar, mainly involved in RNA metabolism, nucleic acid metabolism, ATP metabolism, protein translation, translation regulation and catabolism. The principal component analysis (PCA) showed that the molecular basis of salivary gland of RJBs and ITBs had exerted varying extent of differentiation during the selective breeding. Quantitatively, the PGld of ITBs and RJBs expressed 254 and 333 up-regulated proteins, respectively, corresponding to the small molecule and carbohydrate metabolism pathway in ITBs, and the organic nitrogen compound synthesis, cell redox homeostasis, amino acid metabolism in RJBs. Those proved that the protein synthesis, amino acid metabolism and energy supply of salivary gland cells in RJBs were more active than ITBs. In the same way, the up-regulated expressions of 412 and 162 proteins were detected in the ThGld of ITBs and RJBs, respectively, which involved in the pathways of oxidative phosphorylation, translation regulation in ITBs, and oxidative phosphorylation, response to toxic substances in RJBs, indicating that the level of resistance of RJBs ThGld cells was increased. A total of 43 secretory proteins were identified in the salivary glands of RJBs and ITBs, in which 15 were detected in royal jelly. Major royal jelly proteins 1, 2, 3, 4, 5 and 7 were detected in PGld and ThGld, indicating that both of the glands were involved in the synthesis of royal jelly main protein. The identification of α-glucosidase related to nectar transformation and odorant binding proteins 3, 13, 17 and 21 involved in the synthesis and release of chemical pheromones in both PGld and ThGld indicated their basic function of nectar transformation and pheromone synthesis. The enhanced expression of major royal jelly proteins 1, 2, 3 and 7, hexamerin 70a and 110, odorant binding proteins 3, 13, 17 and 21, transferrin and apolipophorin-III-like protein in the salivary gland of RJBs demonstrated that the synthesis of pheromone and royal jelly protein was stronger than ITBs.【Conclusion】The core proteome with similar pattern in salivary glands of RJBs and ITBs ensures the synthesis and secretion of royal jelly protein, pheromone and invertase. Molecular variation between the salivary glands of RJBs and ITBs was developed after long-term selective breeding. Relative to ITBs, the salivary glands of RJBs enhance the ability of protein synthesis, amino acid metabolism, cell energy supply and stress resistance, and upregulate the expression of most secretory proteins, which benefits to a better protein synthesis system with promising efficiency and lasting, and contributes to the high producing of royal jelly.

The honeybee species A. mellifera and A. cerana have evolved substantial differences in olfactory-driven behaviors and in peripheral olfactory systems. Knowledge of the central nervous system regulating these olfaction differences is limited, however. We compared the phosphoproteome of the antennal lobes (ALs, the primary olfactory neuropil) of A. mellifera and A. cerana, and identified a total of 2812 phosphopeptides carrying 2971 phosphosites from 1265 phosphoproteins. Of these, 76% of the phosphoproteins were shared by both species, which were mainly presynapse and cytoskeleton components, and were involved in signal transduction and neurotransmitter secretion. This finding indicates the fundamental role of protein phosphorylation in regulating signal transduction in the ALs. The mTOR signaling pathway, the phagosome pathway, and the autophagy pathway, which are important in protein metabolism, were enriched, suggesting glomeruli plasticity and olfactory processing are intensively modulated by phosphorylation via these pathways. Compared with A. mellifera, 107 phosphoproteins associated with protein metabolism and transport were uniquely expressed in A. cerana, indicating the protein synthesis-dependent synaptic plasticity is enhanced in A. cerana to facilitate the processing of more complex floral odor clues in mountain foraging areas. This finding is further supported by the significantly upregulated key phosphoproteins of the mTOR signaling pathway in A. cerana ALs. These results provide insights into the phosphoproteomic basis of neuroplasticity that is coupled with the divergent evolution of bees in different environments. SIGNIFICANCE: To adapt to their own ecological niche, the two major honeybee species, A. mellifera and A. cerana, have developed significant difference in olfactory-driven behaviors, but our understanding of the underlying regulation of the central nervous system is still limitate. Here we performed the first comprehensive phosphoproteomic comparison of antennal lobes (Als) between A. mellifera and A. cerena. A large proportion of the identified phosphosites and phosphoproteins were shared between the two species to serve as a core network in the regulation of signal transduction and glomeruli plasticity of ALs. However, compared with A. mellifera, 107 phosphoproteins associated with protein metabolism and transport were uniquely identified in A. cerana ALs, and also several key phosphoproteins in mTOR signaling pathway were found upregulated in A. cerana. These findings indicate protein phosphorylation enhanced the protein synthesis-dependent synaptic plasticity in A. cerana to facilitate the processing of more complex floral odor clues in mountain foraging areas. Our data provide a valuable insight into phosphoproteome-driven cerebral regulation of honeybee olfactory behaviors, which is potentially useful for further neurobiological investigation in both honeybees and other insects.

Over 90% of global royal jelly (RJ), a functional food with various health benefits, is produced in China mainly by migratory beekeeping of a high RJ-producing honeybee (RJB) strain. To explore quality changes of RJ produced by migratory RJBs at different floral periods, we performed metabolomics and proteomics analysis and assessed RJ antioxidant activity. Overall, the RJ metabolic and proteomic profiles were observed to vary with floral periods. Minor sugars (raffinose, erlose, and sucrose) and major RJ protein 5 (MRJP5) were identified among the discriminating components mainly contributing to the altered profiles. Water, crude protein, and the trans-10-hydroxy-2-decenoic acid (10-HDA) content fulfill the requirements of the International Organization for Standardization regardless of floral periods. Notably, the 10-HDA content increased 11.05%-19.65% during tea blooming. Moreover, changes in antioxidants resulted in significant difference in RJ antioxidant activity. The integrated omics data provide a detailed view of chemical composition for RJ quality evaluation.

Mitochondrial genomes (mitogenomes) are involved in cellular energy metabolism and have been shown to undergo adaptive evolution in organisms with increased energy-consuming activities. The genetically selected high royal jelly-producing bees (RJBs, Apis mellifera ligustica) in China can produce 10 times more royal jelly, a highly nutritional and functional food, relative to unselected Italian bees (ITBs). To test for potential adaptive evolution of RJB mitochondrial genes, we sequenced mitogenomes from 100 RJBs and 30 ITBs. Haplotype network and phylogenetic analysis indicate that RJBs and ITBs are not reciprocally monophyletic but mainly divided into the RJB- and ITB-dominant sublineages. The RJB-dominant sublineage proportion is 6-fold higher in RJBs (84/100) than in ITBs (4/30), which is mainly attributable to genetic drift rather than positive selection. The RJB-dominant sublineage exhibits a low genetic diversity due to purifying selection. Moreover, mitogenome abundance is not significantly different between RJBs and ITBs, thereby rejecting the association between mitogenome copy number and royal jelly-producing performance. Our findings demonstrate low genetic diversity levels of RJB mitogenomes and reveal genetic drift and purifying selection as potential forces driving RJB mitogenome evolution.

Protein phosphorylation is essential in a variety of biological activities. Notably, phosphoproteomics has opened new possibilities for honey bee biological study at the molecular and biochemical levels, considering the advancements in LC-MS/MS apparatus and computational analysis. This review extensively evaluated recent advances in honey bee biology utilizing phosphoproteomics methodologies in terms of progressive physiology, age polytheism, and biological changes in some organs, tissues, and cells. Furthermore, a comprehensive phosphoproteomic is necessary for new insight into honey bee biology, a better understanding of the research subject, and determining prospective future research areas.

Reproduction involves the investment of resources into offspring. Although variation in reproductive effort often affects the number of offspring, adjustments of propagule size are also found in numerous species, including the Western honey bee, Apis mellifera . However, the proximate causes of these adjustments are insufficiently understood, especially in oviparous species with complex social organization in which adaptive evolution is shaped by kin selection. Here, we show in a series of experiments that queens predictably and reversibly increase egg size in small colonies and decrease egg size in large colonies, while their ovary size changes in the opposite direction. Additional results suggest that these effects cannot be solely explained by egg-laying rate and are due to the queens’ perception of colony size. Egg-size plasticity is associated with quantitative changes of 290 ovarian proteins, most of which relate to energy metabolism, protein transport, and cytoskeleton. Based on functional and network analyses, we further study the small GTPase Rho1 as a candidate regulator of egg size. Spatio-temporal expression analysis via RNAscope and qPCR supports an important role of Rho1 in egg-size determination, and subsequent RNAi-mediated gene knockdown confirmed that Rho1 has a major effect on egg size in honey bees. These results elucidate how the social environment of the honey bee colony may be translated into a specific cellular process to adjust maternal investment into eggs. It remains to be studied how widespread this mechanism is and whether it has consequences for population dynamics and epigenetic influences on offspring phenotype in honey bees and other species.

Patulin is a common contaminant that frequently occurs in apple fruits and their derived products and constitutes a serious threat to human health. In the present work, the yeast strain Pichia guilliermondii S15-8, with high patulin degradation ability, was screened from nine probiotic yeasts. Subsequently, the optimum degradation conditions were finally established at 30 degrees C in 5 mL of juice simulated solution with 1.0 mg/L initial patulin for 24 h of degradation, and more than 90% of patulin could be degraded with a cell density of 1 x 10(8) cells/mL. Further investigation of the patulin stress response indicated that Pichia guilliermondii S15-8 had a strong tolerance to high patulin stress, even up to 100 mg/L. Furthermore, the product of intracellular enzyme degradation of patulin was identified as E-ascladiol through HPLC and LC-MS. These results corroborated the potential of probiotic Pichia guilliermondii S15-8 for patulin detoxification of apple-derived products.

Innate immune systems are key defenses of animals and particularly important in species that lack the sophisti-cated adaptive immune systems as found in vertebrates. Here, we were interested to quantify variation in innate immune responses of insects in hosts that differ in their parasite susceptibility. To do this, we studied immune responses in honey bees, which can host a remarkable number of different parasites, which are major contribu-tors of declining bee health and colony losses. The most significant parasite of honey bees is the mite Varroa destructor, which has infested the majority of global honey bee populations, and its control remains a major challenge for beekeepers. However, a number of nonmanaged honey bees seem able to control Varroa infections, for example, the Eastern honey bee Apis cerana cerana or the African honey bee Apis mellifera scutellata. These bees therefore make interesting study subjects to identify un-derlaying resistance traits, for example, by comparing them to more susceptible bee genotypes such as Western honey bees (A. mellifera ligustica). We conducted a series of interlinked experiments and started with behavioral assays to compare the attractiveness of bee larvae to mites using different honey bee genotypes and castes. We found that 6-day-old larvae are always most attractive to mites, independently of genotype or castes. In a next step, we compared volatile profiles of the most attractive larvae to test whether they could be used by mites for host se-lection. We found that the abundance of volatile com-pounds differed between larval ages, but we also found significant differences between genotypes and castes. To further study the expected underlaying physiological dif-ferences between potentially resistant and susceptible host larvae, we compared the larval hemolymph pro-teomes of the three honey bee genotypes and two castes in response to mite exposure. We identified consistent upregulation of immune and stress-related genes in Var-roa-exposed larvae, which differed between genotypes and castes. Tolerant honey bee castes and genotypes were characterized by stronger or more distinct immune esponses. In summary, we provide first insights into the complex involvement of the innate immune system of tolerant honey bees against mite infestations, which could be used for future breeding purposes.

The most important honey bee queen food royal jelly is produced by the exocrine hypopharyngeal glands (HGs) of the worker honey bees. The HGs exhibits diverse gene and protein that create age-related physiological adaptations. However, limited knowledge is available on how the phosphorylation process is responsible for physiological alterations across the development of HGs in newly emerged bees. This study measured the acinus of HGs and characterized its phosphoproteomics analysis between the newly emerged bees of royal jelly bees (RJBs) and Italian bees (ITBs). Phosphopeptides of HGs were enriched by Ti4+-IMAC reagents, followed by protein identification via Q-Exactive LC-MS/MS. Our findings indicated that the mean acinus size of HGs of newly emerged bees of RJBs was significantly larger (56.18 ± 1.72 µm) than ITBs (45.98 ± 1.62 µm). A total of 1576 phosphopeptides with 1800 phosphosites containing 525 phosphoproteins were identified in RJBs, while 746 phosphopeptides, of which 846 phosphosites correspond to 317 phosphoproteins were identified in ITBs. Most proteins were phosphorylated on 1 residue followed by 2 and 3 residues in newly emerged bees of both bee stocks. In addition, serine phosphorylation was most observed, followed by threonine and tyrosine in both bee stocks. In newly emerged bees of RJBs, the protein metabolic process, glycolytic process, and formation of translation preinitiation were uniquely enriched, while protein translation, peptide metabolic process and elongation were enriched in ITBs. This research shows detailed phosphorylation of HGs and provides helpful information for understanding the biological activities of HGs development in newly emerged bees from both bee stocks.