![]() ![]() ![]() ![]() IR8a is normally co-expressed with IRs tuned to acids, while IR25a and IR76b are co-expressed with IRs responding to amines. These receptors display more complex combinations since at least three IRs (IR8a, IR25a, and IR76b) can function as co-receptors of specific tuning IRs. Similar to the ORs that are co-expressed with the conserved odorant receptor co-receptor (Orco) to form a functional ligand-gated ion channel, co-expression in neurons is also observed among insect IRs. IRs were first identified in the model insect Drosophila melanogaster as odorant sensing receptors, and subsequent studies extended our knowledge on their functions to the involvement in taste, temperature, humidity and even auditory sensing. Insect IRs are present in different tissues and are more diverse in function. However, the expression pattern and function of the IR family differ from the three well-studied iGluR subfamilies kainate, NMDA (N-methyl-D-aspartate) and AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptors that are expressed on the surface of synapses in animal nervous systems and play a role in signal transmission between neurons. IRs originated from the ionotropic glutamate receptor (iGluR) gene family and share similar structure and mechanism of action as iGluRs. In Drosophila, these two receptor families are present in the dendritic membrane of the olfactory sensory neurons (OSNs) housed in different types of sensilla with distinct chemical preferences: ORs expressed predominantly in trichoid and basiconic sensilla detect, for example, pheromones and plant volatiles, including alcohols, aldehydes, esters and aromatics IRs, mainly expressed in coeloconic sensilla, primarily respond to acids and amines. In insects, airborne chemicals are mainly detected by ligand-activated receptors from two families, namely the odorant receptors (ORs) and ionotropic receptors (IRs). The peripheral process of chemoreception relies on receptors that interact with external molecular cues, triggering the transduction of chemical signals into electrical signals, which may ultimately result in a behavior. Insects have evolved the ability to accurately sense environmental chemical signals, which play critical roles for their survival and reproduction. In addition, using fluorescence in situ hybridization, we demonstrated that the five IRs and their co-receptor AsegIR8a are not located in coeloconic sensilla as found in Drosophila, but in basiconic or trichoid sensilla. segetum, while only octanoic acid had repellent effect to the moths in a behavioral assay. We show that the C 6-C 10 medium-chain fatty acids elicited antennal responses of both sexes of A. It has been reported that the C 6-C 10 medium-chain fatty acids repel various insects including many drosophilids and mosquitos. AsegIR75p.1 responded to several compounds but hexanoic acid was revealed to be the primary ligand, and AsegIR75q.1 responded primarily to octanoic acid, and less so to nonanoic acid. We functionally assayed each of the five AsegIRs from this clade using Xenopus oocytes and found that two receptors responded to the tested ligands. We observed that a large clade formed by IR75p and IR75q expansions is closely related to the acid-sensing IRs identified in Diptera. Here, we identified a repertoire of 26 IRs from transcriptomes of female and male antennae, and ovipositors in the moth Agrotis segetum. The Creative Commons Public Domain Dedication waiver ( ) applies to the data made available in this article, unless otherwise stated in a credit line to the data. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. Open AccessThis article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |