(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Eukaryota: NE > Opisthokonta: NE > Metazoa: NE > Eumetazoa: NE > Bilateria: NE > Protostomia: NE > Ecdysozoa: NE > Panarthropoda: NE > Arthropoda: NE > Mandibulata: NE > Pancrustacea: NE > Hexapoda: NE > Insecta: NE > Dicondylia: NE > Pterygota: NE > Neoptera: NE > Holometabola: NE > Hymenoptera: NE > Apocrita: NE > Aculeata: NE > Apoidea: NE > Apidae: NE > Apinae: NE > Apini: NE > Apis: NE > Apis mellifera: NE
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA MPRNRNSLTKFEVLMVLSLTVLVQLDVCRCTPSHRSRHHADMSYEDTMSF RSGEELPRPAALNSNDDPLIVQTRKGKVRGKTMTATTGKEVDAWFGIPYA QKPLESLRFRHPRPAERWSGILNATTLPNSCVQILDTVFGEFAGATMWNP NTPLSEDCLYVNVVVPRPRPTNAAVMVWIFGGGFYSGSATLDVYDHKTLV SEEKVILVSMQYRVASLGFLYFGTPDVPGNAGLFDQVMALEWVRDNIAAF GGNPDNVTLFGESAGAVSVSMHLLSPLSRHLFNQAIMQSGSPTAPWAIIS REESIVRGIRLAEAVGCPHDRDNLQEVIDCLRVKDPVELVKNEWGTLGIC EFPFVPVIDGAFLDETPQRSLATSSFKKANIMMGSNTEEGFYFIIYYLTE LFHIDGSEVKVSREQFISAVSELNPYVNQFGRRAIIYEYTDWLRPDDPHA NRDALDKIVGDYQFTCNVNEFAGRYTDTGNTVYMYYYKHRSMNNPWPRWT GVMHADEISYVFGEPLDPTKGYTPEEVNLSKKMMRYWANFAKTGDPNVGD VDVWTQAYWPPHTAAKKEYMTLDTNSSEIGNGPRVRQCIFWKNYLPQLVA GTSKLEPKETCSGTRVNDGGRLLLVLSLVVIGTLFSHRIATRAYDELPEI FDPKGFV
References
Title: Acetylcholine titre regulation by non-neuronal acetylcholinesterase 1 and its putative roles in honey bee physiology Kim S, Seong KM, Lee SH Ref: Insect Molecular Biology, :, 2023 : PubMed
Similar to other insects, honey bees have two acetylcholinesterases (AChEs), AmAChE1 and AmAChE2. The primary catalytic enzyme for acetylcholine (ACh) hydrolysis in synapses is AmAChE2, which is predominantly expressed in neuronal tissues, whereas AmAChE1 is expressed in both neuronal and non-neuronal tissues, with limited catalytic activity. Unlike constitutively expressed AmAChE2, AmAChE1 expression is induced under stressful conditions such as heat shock and brood rearing suppression, but its role in regulating ACh titre remains unclear. In this paper, to elucidate the role of AmAChE1, the expression of AmAChE1 was suppressed via RNA interference (RNAi) in AmAChE1-induced worker bees. The ACh titre measurement following RNAi revealed that the expression of AmAChE1 downregulated the overall ACh titre in all tissues examined without altering AmAChE2 expression. Transcriptome analysis showed that AmAChE1 knockdown upregulated protein biosynthesis, cell respiration, and thermogenesis in the head. These findings suggest that AmAChE1 is involved in decreasing neuronal activity, enhancing energy conservation, and potentially extending longevity under stressful conditions via ACh titre regulation.
Title: Expression of acetylcholinesterase 1 is associated with brood rearing status in the honey bee, Apis mellifera Kim YH, Kim JH, Kim K, Lee SH Ref: Sci Rep, 7:39864, 2017 : PubMed
Acetylcholinesterase 1 (AmAChE1) of the honey bee, Apis mellifera, has been suggested to have non-neuronal functions. A systematic expression profiling of AmAChE1 over a year-long cycle on a monthly basis revealed that AmAChE1 was predominantly expressed in both head and abdomen during the winter months and was moderately expressed during the rainy summer months. Interestingly, AmAChE1 expression was inhibited when bees were stimulated for brood rearing by placing overwintering beehives in strawberry greenhouses with a pollen diet, whereas it resumed when the beehives were moved back to the cold field, thereby suppressing brood rearing. In early spring, pollen diet supplementation accelerated the induction of brood-rearing activity and the inhibition of AmAChE1 expression. When active beehives were placed in a screen tent in late spring, thereby artificially suppressing brood-rearing activity, AmAChE1 was highly expressed. In contrast, AmAChE1 expression was inhibited when beehives were allowed to restore brood rearing by removing the screen, supporting the hypothesis that brood rearing status is a main factor in the regulation of AmAChE1 expression. Since brood rearing status is influenced by various stress factors, including temperature and diet shortage, our finding discreetly suggests that AmAChE1 is likely involved in the stress response or stress management.
Title: Molecular and kinetic properties of two acetylcholinesterases from the western honey bee, Apis mellifera Kim YH, Cha DJ, Jung JW, Kwon HW, Lee SH Ref: PLoS ONE, 7:e48838, 2012 : PubMed
We investigated the molecular and kinetic properties of two acetylcholinesterases (AmAChE1 and AmAChE2) from the Western honey bee, Apis mellifera. Western blot analysis revealed that AmAChE2 has most of catalytic activity rather than AmAChE1, further suggesting that AmAChE2 is responsible for synaptic transmission in A. mellifera, in contrast to most other insects. AmAChE2 was predominately expressed in the ganglia and head containing the central nervous system (CNS), while AmAChE1 was abundantly observed not only in the CNS but also in the peripheral nervous system/non-neuronal tissues. Both AmAChEs exist as homodimers; the monomers are covalently connected via a disulfide bond under native conditions. However, AmAChE2 was associated with the cell membrane via the glycophosphatidylinositol anchor, while AmAChE1 was present as a soluble form. The two AmAChEs were functionally expressed with a baculovirus system. Kinetic analysis revealed that AmAChE2 has approximately 2,500-fold greater catalytic efficiency toward acetylthiocholine and butyrylthiocholine than AmAChE1, supporting the synaptic function of AmAChE2. In addition, AmAChE2 likely serves as the main target of the organophosphate (OP) and carbamate (CB) insecticides as judged by the lower IC(50) values against AmAChE2 than against AmAChE1. When OP and CB insecticides were pre-incubated with a mixture of AmAChE1 and AmAChE2, a significant reduction in the inhibition of AmAChE2 was observed, suggesting a protective role of AmAChE1 against xenobiotics. Taken together, based on their tissue distribution pattern, molecular and kinetic properties, AmAChE2 plays a major role in synaptic transmission, while AmAChE1 has non-neuronal functions, including chemical defense.
