Brain Membrane Proteome and Phosphoproteome Reveal Molecular Basis Associating with Nursing and Foraging Behaviors of Honeybee Workers

Abstract

The brain is a vital organ in regulating complex social behaviors of honeybees including learning and memory. Knowledge of how brain membrane proteins and their phosphorylation underlie the age-related behavioral polyethism is still lacking. A hitherto age-resolved brain membrane proteome and phosphoproteome were reported in adult worker bees from two strains of honeybee (Apis mellifera ligustica): Italian bee (ITB) and Royal Jelly bee (RJB), a line selected from ITB for increased RJ outputs over four decades. There were 1079 membrane protein groups identified, and 417 unique phosphosites were located in 179 membrane protein groups mainly phosphorylated by kinase families of MAPKs, CDKs, and CK2. Age-resolved dynamics of brain membrane proteome and phosphoproteome are indicative of their correlation with the neurobiological requirements during the adult life of honeybee workers. To stimulate immature brain cell development in newly emerged bees (NEBs), the enriched functional classes associated with metabolism of carbohydrates, nucleosides, and lipids by the up-regulated proteins suggest their enhanced role in driving cell maturity of the brain. In nurse bees (NBs) and forager bees (FBs), a higher number of membrane proteins and phosphoproteins were expressed as compared with in the young stages, and the enriched signal-transduction-related pathways by the up-regulated proteins suggest their significances in sustaining the intensive information processing during nursing and foraging activities. Notably, RJB has shaped unique membrane proteome and phosphoproteome settings to consolidate nursing and foraging behaviors in response to decades of selection underpinning the elevated RJ yields. In RJB NBs, the enriched pathways of phosphatidylinositol signaling and arachidonic acid metabolism indicate a stronger olfaction sensation in response to larval pheromone stimulation. In RJB FBs, the enriched pathways related to signal processing such as SNARE interactions in vesicular transport, wnt signaling, TGF-beta signaling, and taurine and hypotaurine metabolism suggest an enhanced nerve sensitivity to prime the stronger tendency to pollen collection. Our data gain a novel insight into membrane proteome and phosphoproteome-driven cerebral regulation of honeybee behaviors, which is potentially useful for further neurobiological investigation in both honeybees and other social insects.

Proteome Changes Paralleling the Olfactory Conditioning in the Forager Honey Bee and Provision of a Brain Proteomics Dataset

“…Despite the well‐known role of SNAREs in neuronal communication, the information on their memory‐specific functions is limited. Interestingly, the SNARE members have been previously implicated in foraging behavior of honeybees based on the comparative proteomics of different species . Here, we propose that the modulation of BET1‐homolog and VAMP7 proteins observed in our data reflects their engagement in olfactory conditioning and PER of the bees.…”

“…To reveal molecular elements involved in olfactory memory of PER, previous studies applied gene knockdown and/or neuropharmacological inhibition strategies, transcriptomic analyses . The bee brain proteome was characterized regarding individual species, brain regions, and/or developmental stages with the potential implications in the corresponding behavioral changes; however, no specific memory paradigm has been addressed. We previously reported the proteomics changes associated with the PER .…”

Molecular insights into the enhanced performance of royal jelly secretion by a stock of honeybee (Apis mellifera ligustica) selected for increasing royal jelly production

“…Proteomics is becoming an important tool for describing bee biology at the molecular level (Zewdu Ararso et al 2018). The molecular basis of different organs and tissues that allow bees to perform their biological tasks has been explained on the proteome scale, for example in the brain (Hernandez et al 2012;Chan et al 2013;Han et al 2015;Han et al 2017;Meng et al 2018), hemolymph (Ararso et al 2018), embryo (Fang et al 2014;Fang et al 2015), antennae in Varroa resistance (Parker et al 2012;Hu et al 2016), and venom (Matysiak et al 2014;Matysiak et al 2016;Matysiak et al 2017).…”

“…Also, in RJBs enhanced levels of neuropeptides are involved in regulating water homeostasis, brooder pheromone recognition, foraging ability, and pollen collection to regulate RJ secretion behavior (Han et al 2015). Moreover, in nurses of RJB, the activity of phosphatidylinositol signaling and arachidonic acid metabolism is increased to enhance the olfactory response to larval pheromone stimulation (Han et al 2017). The mandibular gland of RJB also selectively improved lipid synthesis-related pathways to maintain an appropriate ratio of 10hydroxy-2-decenoic acid, an important fatty acid in RJ, for larval nutrition, also contributes to the increase RJ production (Huo et al 2016).…”

“…Although these markers are important for marker-based selection, knowledge on the molecular mechanism that drives the stronger performance of RJ production by RJBs is still required. To be noted, recent proteome researches have revealed that RJBs have reshaped the proteome setting of the HGs (Li et al 2010;Ji et al 2014), mandibular glands (MGs) (Huo et al 2016), hemolymph (Ararso et al 2018), and nervous system (Han et al 2015;Han et al 2017), to support their biological performance for the elevated RJ production, as compared to ITBs and other honeybee species and/or lines. In addition, proteome, phosphoproteome, and glycoproteome comparisons of RJ from RJBs and/or other honeybee species/lines have been carried out (Li et al 2007a, b;Chen and Li 2009;Fang et al 2010).…”