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1.
Genesis ; 62(3): e23610, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38874301

RESUMO

The organization of the olfactory glomerular map involves the convergence of olfactory sensory neurons (OSNs) expressing the same odorant receptor (OR) into glomeruli in the olfactory bulb (OB). A remarkable feature of the olfactory glomerular map formation is that the identity of OR instructs the topography of the bulb, resulting in thousands of discrete glomeruli in mice. Several lines of evidence indicate that ORs control the expression levels of various kinds of transmembrane proteins to form glomeruli at appropriate regions of the OB. In this review, we will discuss how the OR identity is decoded by OSNs into gene expression through intracellular regulatory mechanisms.


Assuntos
Bulbo Olfatório , Neurônios Receptores Olfatórios , Receptores Odorantes , Animais , Camundongos , Bulbo Olfatório/metabolismo , Neurônios Receptores Olfatórios/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo
2.
J Cell Mol Med ; 28(11): e18366, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38856956

RESUMO

Ischemic stroke is one of the main causes of disability and death. However, recanalization of occluded cerebral arteries is effective only within a very narrow time window. Therefore, it is particularly important to find neuroprotective biological targets for cerebral artery recanalization. Here, gene expression profiles of datasets GSE160500 and GSE97537 were downloaded from the GEO database, which were related to ischemic stroke in rats. Olfactory receptor 78 (Olfr78) was screened, and which highly associated with Calcium signalling pathway and MAPK pathway. Interacting protein of Olfr78, Prkaca, was predicted by STRING, and their interaction was validated by Co-IP analysis. Then, a rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) and a neuronal cell model stimulated by oxygen-glucose deprivation/reoxygenation (OGD/R) were constructed, and the results showed that expression of Olfr78 and Prkaca was downregulated in MCAO rats and OGD/R-stimulated neurons. Overexpression of Olfr78 or Prkaca inhibited the secretion of inflammatory factors, Ca2+ overload, and OGD/R-induced neuronal apoptosis. Moreover, Overexpression of Prkaca increased protein levels of cAMP, PKA and phosphorylated p38 in OGD/R-stimulated neurons, while SB203580, a p38 inhibitor, treatment inhibited activation of the cAMP/PKA-MAPK pathway and counteracted the effect of Olfr78 overexpression on improvement of neuronal functions. Meanwhile, overexpression of Olfr78 or Prkaca markedly inhibited neuronal apoptosis and improved brain injury in MCAO/R rats. In conclusion, overexpression of Olfr78 inhibited Ca2+ overload and reduced neuronal apoptosis in MCAO/R rats by promoting Prkaca-mediated activation of the cAMP/PKA-MAPK pathway, thereby improving brain injury in cerebral ischaemia-reperfusion.


Assuntos
Apoptose , AMP Cíclico , Ratos Sprague-Dawley , Receptores Odorantes , Traumatismo por Reperfusão , Animais , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/genética , Ratos , Masculino , AMP Cíclico/metabolismo , Receptores Odorantes/metabolismo , Receptores Odorantes/genética , Isquemia Encefálica/metabolismo , Isquemia Encefálica/genética , Isquemia Encefálica/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Lesões Encefálicas/metabolismo , Lesões Encefálicas/etiologia , Lesões Encefálicas/patologia , Neurônios/metabolismo , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/metabolismo , Transdução de Sinais
3.
Genesis ; 62(3): e23611, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38888221

RESUMO

Olfactory sensory neurons (OSNs) are one of a few neuron types that are generated continuously throughout life in mammals. The persistence of olfactory sensory neurogenesis beyond early development has long been thought to function simply to replace neurons that are lost or damaged through exposure to environmental insults. The possibility that olfactory sensory neurogenesis may also serve an adaptive function has received relatively little consideration, largely due to the assumption that the generation of new OSNs is stochastic with respect to OSN subtype, as defined by the single odorant receptor gene that each neural precursor stochastically chooses for expression out of hundreds of possibilities. Accordingly, the relative birthrates of different OSN subtypes are predicted to be constant and impervious to olfactory experience. This assumption has been called into question, however, by evidence that the birthrates of specific OSN subtypes can be selectively altered by manipulating olfactory experience through olfactory deprivation, enrichment, and conditioning paradigms. Moreover, studies of recovery of the OSN population following injury provide further evidence that olfactory sensory neurogenesis may not be strictly stochastic with respect to subtype. Here we review this evidence and consider mechanistic and functional implications of the prospect that specific olfactory experiences can regulate olfactory sensory neurogenesis rates in a subtype-selective manner.


Assuntos
Neurogênese , Neurônios Receptores Olfatórios , Receptores Odorantes , Animais , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Neurônios Receptores Olfatórios/metabolismo , Neurônios Receptores Olfatórios/fisiologia , Neurogênese/genética , Olfato/fisiologia , Olfato/genética , Humanos
4.
Int J Mol Sci ; 25(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38892263

RESUMO

The cell surface metalloprotease ADAM17 (a disintegrin and metalloprotease 17) and its binding partners iRhom2 and iRhom1 (inactive Rhomboid-like proteins 1 and 2) modulate cell-cell interactions by mediating the release of membrane proteins such as TNFα (Tumor necrosis factor α) and EGFR (Epidermal growth factor receptor) ligands from the cell surface. Most cell types express both iRhoms, though myeloid cells exclusively express iRhom2, and iRhom1 is the main iRhom in the mouse brain. Here, we report that iRhom2 is uniquely expressed in olfactory sensory neurons (OSNs), highly specialized cells expressing one olfactory receptor (OR) from a repertoire of more than a thousand OR genes in mice. iRhom2-/- mice had no evident morphological defects in the olfactory epithelium (OE), yet RNAseq analysis revealed differential expression of a small subset of ORs. Notably, while the majority of ORs remain unaffected in iRhom2-/- OE, OSNs expressing ORs that are enriched in iRhom2-/- OE showed fewer gene expression changes upon odor environmental changes than the majority of OSNs. Moreover, we discovered an inverse correlation between the expression of iRhom2 compared to OSN activity genes and that odor exposure negatively regulates iRhom2 expression. Given that ORs are specialized G-protein coupled receptors (GPCRs) and many GPCRs activate iRhom2/ADAM17, we investigated if ORs could activate iRhom2/ADAM17. Activation of an olfactory receptor that is ectopically expressed in keratinocytes (OR2AT4) by its agonist Sandalore leads to ERK1/2 phosphorylation, likely via an iRhom2/ADAM17-dependent pathway. Taken together, these findings point to a mechanism by which odor stimulation of OSNs activates iRhom2/ADAM17 catalytic activity, resulting in downstream transcriptional changes to the OR repertoire and activity genes, and driving a negative feedback loop to downregulate iRhom2 expression.


Assuntos
Neurônios Receptores Olfatórios , Receptores Odorantes , Animais , Receptores Odorantes/metabolismo , Receptores Odorantes/genética , Camundongos , Neurônios Receptores Olfatórios/metabolismo , Olfato/fisiologia , Proteína ADAM17/metabolismo , Proteína ADAM17/genética , Camundongos Knockout , Proteínas de Transporte/metabolismo , Proteínas de Transporte/genética , Mucosa Olfatória/metabolismo , Regulação da Expressão Gênica , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Humanos
5.
PLoS One ; 19(6): e0301177, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38848419

RESUMO

In the polyphagous insect Monolepta signata (M. signata) (Coleoptera: Chrysomelidae), antennae are important for olfactory reception used during feeding, mating, and finding a suitable oviposition site. Based on NextSeq 6000 Illumina sequencing, we assembled the antennal transcriptome of mated M. signata and described the first chemosensory gene repertoire expressed in this species. The relative expression levels of some significant chemosensory genes were conducted by quantitative real-time PCR. We identified 114 olfactory-related genes based on the antennal transcriptome database of M. signata, including 21 odorant binding proteins (OBPs), six chemosensory proteins (CSPs), 46 odorant receptors (ORs), 15 ionotropic receptors (IRs), 23 gustatory receptors (GRs) and three sensory neuron membrane proteins (SNMPs). Blastp best hit and phylogenetic analyses showed that most of the chemosensory genes had a close relationship with orthologs from other Coleoptera species. Overall, this study provides a foundation for elucidating the molecular mechanism of olfactory recognition in M. signata as well as a reference for the study of chemosensory genes in other species of Coleoptera.


Assuntos
Antenas de Artrópodes , Besouros , Proteínas de Insetos , Filogenia , Receptores Odorantes , Transcriptoma , Animais , Besouros/genética , Antenas de Artrópodes/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Proteínas de Insetos/genética , Feminino , Perfilação da Expressão Gênica
6.
Sci Adv ; 10(23): eadk9000, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38848359

RESUMO

Olfaction is essential for complex social behavior in insects. To discriminate complex social cues, ants evolved an expanded number of odorant receptor (Or) genes. Mutations in the obligate odorant co-receptor gene orco lead to the loss of ~80% of the antennal lobe glomeruli in the jumping ant Harpegnathos saltator. However, the cellular mechanism remains unclear. Here, we demonstrate massive apoptosis of odorant receptor neurons (ORNs) in the mid to late stages of pupal development, possibly due to ER stress in the absence of Orco. Further bulk and single-nucleus transcriptome analysis shows that, although most orco-expressing ORNs die in orco mutants, a small proportion of them survive: They express ionotropic receptor (Ir) genes that form IR complexes. In addition, we found that some Or genes are expressed in mechanosensory neurons and nonneuronal cells, possibly due to leaky regulation from nearby non-Or genes. Our findings provide a comprehensive overview of ORN development and Or expression in H. saltator.


Assuntos
Formigas , Neurônios Receptores Olfatórios , Receptores Odorantes , Animais , Neurônios Receptores Olfatórios/metabolismo , Formigas/genética , Formigas/metabolismo , Formigas/fisiologia , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Apoptose , Mutação , Sobrevivência Celular , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Perfilação da Expressão Gênica , Transcriptoma
7.
Proc Natl Acad Sci U S A ; 121(23): e2403796121, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38809710

RESUMO

Olfactory receptors (Olfr) are G protein-coupled receptors that are normally expressed on olfactory sensory neurons to detect volatile chemicals or odorants. Interestingly, many Olfrs are also expressed in diverse tissues and function in cell-cell recognition, migration, and proliferation as well as immune responses and disease processes. Here, we showed that many Olfr genes were expressed in the mouse spleen, linked to Plasmodium yoelii genetic loci significantly, and/or had genome-wide patterns of LOD scores (GPLSs) similar to those of host Toll-like receptor genes. Expression of specific Olfr genes such as Olfr1386 in HEK293T cells significantly increased luciferase signals driven by IFN-ß and NF-κB promoters, with elevated levels of phosphorylated TBK1, IRF3, P38, and JNK. Mice without Olfr1386 were generated using the CRISPR/Cas9 method, and the Olfr1386-/- mice showed significantly lower IFN-α/ß levels and longer survival than wild-type (WT) littermates after infection with P. yoelii YM parasites. Inhibition of G protein signaling and P38 activity could affect cyclic AMP-responsive element promoter-driven luciferase signals and IFN-ß mRNA levels in HEK293T cells expressing the Olfr1386 gene, respectively. Screening of malaria parasite metabolites identified nicotinamide adenine dinucleotide (NAD) as a potential ligand for Olfr1386, and NAD could stimulate IFN-ß responses and phosphorylation of TBK1 and STAT1/2 in RAW264.7 cells. Additionally, parasite RNA (pRNA) could significantly increase Olfr1386 mRNA levels. This study links multiple Olfrs to host immune response pathways, identifies a candidate ligand for Olfr1386, and demonstrates the important roles of Olfr1386 in regulating type I interferon (IFN-I) responses during malaria parasite infections.


Assuntos
Interferon Tipo I , Malária , Plasmodium yoelii , Receptores Odorantes , Animais , Camundongos , Malária/imunologia , Malária/parasitologia , Malária/metabolismo , Humanos , Células HEK293 , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Interferon Tipo I/metabolismo , Interferon Tipo I/imunologia , Camundongos Knockout , Transdução de Sinais , Camundongos Endogâmicos C57BL
8.
Development ; 151(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38813842

RESUMO

This Review elucidates the regulatory principles of random monoallelic expression by focusing on two well-studied examples: the X-chromosome inactivation regulator Xist and the olfactory receptor gene family. Although the choice of a single X chromosome or olfactory receptor occurs in different developmental contexts, common gene regulatory principles guide monoallelic expression in both systems. In both cases, an event breaks the symmetry between genetically and epigenetically identical copies of the gene, leading to the expression of one single random allele, stabilized through negative feedback control. Although many regulatory steps that govern the establishment and maintenance of monoallelic expression have been identified, key pieces of the puzzle are still missing. We provide an overview of the current knowledge and models for the monoallelic expression of Xist and olfactory receptors. We discuss their similarities and differences, and highlight open questions and approaches that could guide the study of other monoallelically expressed genes.


Assuntos
Alelos , RNA Longo não Codificante , Receptores Odorantes , Inativação do Cromossomo X , Animais , Humanos , Inativação do Cromossomo X/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Regulação da Expressão Gênica no Desenvolvimento
9.
Gene ; 923: 148551, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-38759737

RESUMO

Odorant-binding proteins (OBPs) are crucial in insect olfaction. The most abundant expressed OBP of citrus psyllids, DcitOBP9 encodes 148 amino acids. DcitOBP9 lacks a transmembrane structure and possesses a 17-amino acid signal peptide at the N-terminus. Characterized by the six conserved cysteine sites, DcitOBP9 is classified as the Classical-OBP family. RT-qPCR experiments revealed ubiquitous expression of DcitOBP9 across all developmental stages of the citrus psyllid, with predominant expression in adults antennae. Fluorescence competitive binding assays demonstrated DcitOBP9's strong affinity for ocimene, linalool, dodecanoic acid, and citral, and moderate affinity for dimethyl trisulfide. Additionally, it binds to myrcia, (-)-trans-caryophyllene, (±)-Citronellal, nonanal, and (+)-α-pinene. Among them, ocimene, linalool, and dodecanoic acid were dynamically bound to DcitOBP9, while citral was statically bound to DcitOBP9. Molecular docking simulations with the top five ligands indicated that amino acid residues V92, S72, P128, L91, L75, and A76 are pivotal in the interaction between DcitOBP9 and these odorants. These findings suggest DcitOBP9's involvement in the citrus psyllid's host plant recognition and selection behaviors, thereby laying a foundation for elucidating the potential physiological and biological functions of DcitOBP9 and developing attractants.


Assuntos
Hemípteros , Proteínas de Insetos , Simulação de Acoplamento Molecular , Receptores Odorantes , Animais , Hemípteros/genética , Hemípteros/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/química , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Receptores Odorantes/química , Citrus/metabolismo , Citrus/genética , Ligação Proteica , Sequência de Aminoácidos , Filogenia
10.
Artigo em Inglês | MEDLINE | ID: mdl-38723431

RESUMO

The longhorned beetles are key players for the maintenance of biodiversity in the terrestrial ecosystem. As xylophagous cerambycid insects in Coleoptera, the beetles have evolved specialized olfactory and gustatory systems to recognize chemical cues in the surrounding habitats. Despite over 36,000 described species in the Cerambycidae family including a wood-boring pest Pharsalia antennata, only a limited number of them (<1 %) have been characterized regarding their chemical ecology at the molecular level. Here, we surveyed four membrane protein gene families in P. antennata related to chemoreception through transcriptomics, phylogenetics and expression profiling analyses. In total, 144 genes encoding 72 odorant receptors (ORs), 33 gustatory receptors (GRs), 23 ionotropic receptors (IRs), four sensory neuron membrane proteins (SNMPs) and 12 ionotropic glutamate receptors (iGluRs) were harvested from the transcriptome of multiple tissues including antennae and legs of both sexes. The lineage-specific expansion of PantORs possibly implied a diverse range of host plants in this beetle, supporting this correlation between the host range and olfactory receptor repertoire sizes across cerambycid species. Further phylogenetic analysis revealed that Group 2 was contributed mainly to the large OR gene repertoire in P. antennata, representing 18 genes in Group 2A and eight in Group 2B. On the other hand, some key chemosensory genes were identified by applying a phylogenetics approach, such as PantOR21 close to the 2-phenylethanol receptor in Megacyllene caryae, three carbon dioxide GRs and seven Antennal IRs (A-IRs) clades. We also determined sex- and tissue-specific expression profiles of 69 chemosensory genes, revealing the high expression of most PantORs in antennae. Noticeably, 10 sex-biased genes (six PantORs, three PantIRs and PantSNMP1a) were presented in antennae, five sex-biased PantGRs in legs and 39 sex-biased genes (15 PantORs, 13 PantGRs, eight PantIRs and three PantSNMPs) in abdomens. These findings have greatly enhanced our knowledge about the chemical ecology of P. antennata and identify candidate molecular targets for mediating smell and taste of this beetle.


Assuntos
Besouros , Proteínas de Insetos , Filogenia , Animais , Besouros/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Feminino , Transcriptoma , Receptores Ionotrópicos de Glutamato/genética , Receptores Ionotrópicos de Glutamato/metabolismo , Família Multigênica , Antenas de Artrópodes/metabolismo
11.
BMC Genomics ; 25(1): 493, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762533

RESUMO

BACKGROUND: Insects rely on sophisticated sensitive chemosensory systems to sense their complex chemical environment. This sensory process involves a combination of odorant receptors (ORs), gustatory receptors (GRs) and ionotropic receptors (IRs) in the chemosensory system. This study focused on the identification and characterization of these three types of chemosensory receptor genes in two closely related Phthorimaea pest species, Phthorimaea operculella (potato tuber moth) and Phthorimaea absoluta (tomato leaf miner). RESULTS: Based on manual annotation of the genome, we identified a total of 349 chemoreceptor genes from the genome of P. operculella, including 93 OR, 206 GR and 50 IR genes, while for P. absoluta, we identified 72 OR, 122 GR and 46 IR genes. Through phylogenetic analysis, we observed minimal differences in the number and types of ORs and IRs between the potato tuber moth and tomato leaf miner. In addition, we found that compared with those of tomato leaf miners, the gustatory receptor branch of P. operculella has undergone a large expansion, which may be related to P. absoluta having a narrower host range than P. operculella. Through analysis of differentially expressed genes (DEGs) of male and female antennae, we uncovered 45 DEGs (including 32ORs, 9 GRs, and 4 IRs). CONCLUSIONS: Our research provides a foundation for exploring the chemical ecology of these two pests and offers new insights into the dietary differentiation of lepidopteran insects, while simultaneously providing molecular targets for developing environmentally friendly pest control methods based on insect chemoreception.


Assuntos
Evolução Molecular , Mariposas , Filogenia , Receptores Odorantes , Animais , Mariposas/genética , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Família Multigênica , Adaptação ao Hospedeiro/genética , Genômica/métodos , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo
12.
Insect Biochem Mol Biol ; 169: 104129, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38704126

RESUMO

The Asian palm weevil, Rhynchophorus ferrugineus, is a tremendously important agricultural pest primarily adapted to palm trees and causes severe destruction, threatening sustainable palm cultivation worldwide. The host plant selection of this weevil is mainly attributed to the functional specialization of odorant receptors (ORs) that detect palm-derived volatiles. Yet, ligands are known for only two ORs of R. ferrugineus, and we still lack information on the mechanisms of palm tree detection. This study identified a highly expressed antennal R. ferrugineus OR, RferOR2, thanks to newly generated transcriptomic data. The phylogenetic analysis revealed that RferOR2 belongs to the major coleopteran OR group 2A and is closely related to a sister clade containing an R. ferrugineus OR (RferOR41) tuned to the non-host plant volatile and antagonist, α-pinene. Functional characterization of RferOR2 via heterologous expression in Drosophila olfactory neurons revealed that this receptor is tuned to several ecologically relevant palm-emitted odors, most notably ethyl and methyl ester compounds, but not to any of the pheromone compounds tested, including the R. ferrugineus aggregation pheromone. We did not evidence any differential expression of RferOR2 in the antennae of both sexes, suggesting males and females detect these compounds equally. Next, we used the newly identified RferOR2 ligands to demonstrate that including synthetic palm ester volatiles as single compounds and in combinations in pheromone-based mass trapping has a synergistic attractiveness effect to R. ferrugineus aggregation pheromone, resulting in significantly increased weevil catches. Our study identified a key OR from a palm weevil species tuned to several ecologically relevant palm volatiles and represents a significant step forward in understanding the chemosensory mechanisms of host detection in palm weevils. Our study also defines RferOR2 as an essential model for exploring the molecular basis of host detection in other palm weevil species. Finally, our work showed that insect OR deorphanization could aid in identifying novel behaviorally active volatiles that can interfere with weevil host-searching behavior in sustainable pest management applications.


Assuntos
Receptores Odorantes , Gorgulhos , Animais , Gorgulhos/metabolismo , Gorgulhos/genética , Receptores Odorantes/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/química , Compostos Orgânicos Voláteis/metabolismo , Masculino , Filogenia , Feminino , Arecaceae/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/química , Antenas de Artrópodes/metabolismo , Ésteres/metabolismo
13.
PLoS One ; 19(5): e0302496, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38709760

RESUMO

Adult mosquitoes require regular sugar meals, including nectar, to survive in natural habitats. Both males and females locate potential sugar sources using sensory proteins called odorant receptors (ORs) activated by plant volatiles to orient toward flowers or honeydew. The yellow fever mosquito, Aedes aegypti (Linnaeus, 1762), possesses a large gene family of ORs, many of which are likely to detect floral odors. In this study, we have uncovered ligand-receptor pairings for a suite of Aedes aegypti ORs using a panel of environmentally relevant, plant-derived volatile chemicals and a heterologous expression system. Our results support the hypothesis that these odors mediate sensory responses to floral odors in the mosquito's central nervous system, thereby influencing appetitive or aversive behaviors. Further, these ORs are well conserved in other mosquitoes, suggesting they function similarly in diverse species. This information can be used to assess mosquito foraging behavior and develop novel control strategies, especially those that incorporate mosquito bait-and-kill technologies.


Assuntos
Aedes , Flores , Receptores Odorantes , Compostos Orgânicos Voláteis , Animais , Aedes/fisiologia , Aedes/metabolismo , Receptores Odorantes/metabolismo , Receptores Odorantes/genética , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/análise , Feminino , Masculino , Febre Amarela/transmissão , Odorantes/análise , Plantas/metabolismo , Plantas/química
14.
Biochem Biophys Res Commun ; 719: 150062, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38740002

RESUMO

Pluripotent stem cells, such as embryonic stem cells and induced pluripotent stem cells (iPSCs), can differentiate into almost all cell types and are anticipated to have significant applications in the field of regenerative medicine. However, there are no reports of successfully directing iPSCs to become functional olfactory sensory neurons (OSNs) capable of selectively receiving odorant compounds. In this study, we employed dual SMAD inhibition and fibroblast growth factor 8 (FGF-8, reported to dictate olfactory fates) along with N-2 and B-27 supplements in the culture medium to efficiently induce the differentiation of iPSCs into neuronal cells with olfactory function through olfactory placode. Temporal gene expression and expression of OSN-specific markers during differentiation indicated that the expression of olfactory marker proteins and various olfactory receptors (ORs), which are markers of mature OSNs, was observed after approximately one month of differentiation culture, irrespective of the differentiation cues, suggesting differentiation into OSNs. Cells that exhibited specific responses to odorant compounds were identified after administering odorant compounds to differentiated iPSC-derived OSNs. This suggests the spontaneous generation of functional OSNs expressing diverse ORs that respond to odorant compounds from iPSCs.


Assuntos
Diferenciação Celular , Células-Tronco Pluripotentes Induzidas , Odorantes , Neurônios Receptores Olfatórios , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Humanos , Neurônios Receptores Olfatórios/metabolismo , Neurônios Receptores Olfatórios/citologia , Odorantes/análise , Células Cultivadas , Receptores Odorantes/genética , Receptores Odorantes/metabolismo
15.
Mol Pharmacol ; 106(1): 21-32, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38719475

RESUMO

Olfactory receptors are members of class A (rhodopsin-like) family of G protein-coupled receptors (GPCRs). Their expression and function have been increasingly studied in nonolfactory tissues, and many have been identified as potential therapeutic targets. In this manuscript, we focus on the discovery of novel ligands for the olfactory receptor family 51 subfamily E2 (OR51E2). We performed an artificial intelligence-based virtual drug screen of a ∼2.2 million small molecule library. Cell-based functional assay identified compound 80 (C80) as an antagonist and inverse agonist, and detailed pharmacological analysis revealed C80 acts as a negative allosteric modulator by significantly decreasing the agonist efficacy, while having a minimal effect on receptor affinity for agonist. C80 binds to an allosteric binding site formed by a network of nine residues localized in the intracellular parts of transmembrane domains 3, 5, 6, 7, and H8, which also partially overlaps with a G protein binding site. Mutational experiments of residues involved in C80 binding uncovered the significance of the C2406.37 position in blocking the activation-related conformational change and keeping the receptor in the inactive form. Our study provides a mechanistic understanding of the negative allosteric action of C80 on agonist-ctivated OR51E2. We believe the identification of the antagonist of OR51E2 will enable a multitude of studies aiming to determine the functional role of this receptor in specific biologic processes. SIGNIFICANCE STATEMENT: OR51E2 has been implicated in various biological processes, and its antagonists that can effectively modulate its activity have therapeutic potential. Here we report the discovery of a negative allosteric modulator of OR51E2 and provide a mechanistic understanding of its action. We demonstrate that this modulator has an inhibitory effect on the efficacy of the agonist for the receptor and reveal a network of nine residues that constitute its binding pocket, which also partially overlaps with the G protein binding site.


Assuntos
Sítio Alostérico , Receptores Odorantes , Receptores Odorantes/metabolismo , Receptores Odorantes/antagonistas & inibidores , Receptores Odorantes/química , Regulação Alostérica/efeitos dos fármacos , Humanos , Animais , Ligantes , Sítios de Ligação , Células HEK293 , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/química , Cricetulus , Células CHO
16.
Sci Adv ; 10(21): eadl2882, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38781346

RESUMO

Neuromorphic sensors, designed to emulate natural sensory systems, hold the promise of revolutionizing data extraction by facilitating rapid and energy-efficient analysis of extensive datasets. However, a challenge lies in accurately distinguishing specific analytes within mixtures of chemically similar compounds using existing neuromorphic chemical sensors. In this study, we present an artificial olfactory system (AOS), developed through the integration of human olfactory receptors (hORs) and artificial synapses. This AOS is engineered by interfacing an hOR-functionalized extended gate with an organic synaptic device. The AOS generates distinct patterns for odorants and mixtures thereof, at the molecular chain length level, attributed to specific hOR-odorant binding affinities. This approach enables precise pattern recognition via training and inference simulations. These findings establish a foundation for the development of high-performance sensor platforms and artificial sensory systems, which are ideal for applications in wearable and implantable devices.


Assuntos
Odorantes , Receptores Odorantes , Humanos , Receptores Odorantes/metabolismo , Odorantes/análise , Olfato/fisiologia , Sinapses/metabolismo , Reconhecimento Automatizado de Padrão/métodos , Neurônios Receptores Olfatórios/metabolismo , Neurônios Receptores Olfatórios/fisiologia , Técnicas Biossensoriais/métodos
17.
Nat Methods ; 21(6): 974-982, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38622459

RESUMO

The simultaneous measurement of three-dimensional (3D) genome structure and gene expression of individual cells is critical for understanding a genome's structure-function relationship, yet this is challenging for existing methods. Here we present 'Linking mRNA to Chromatin Architecture (LiMCA)', which jointly profiles the 3D genome and transcriptome with exceptional sensitivity and from low-input materials. Combining LiMCA and our high-resolution scATAC-seq assay, METATAC, we successfully characterized chromatin accessibility, as well as paired 3D genome structures and gene expression information, of individual developing olfactory sensory neurons. We expanded the repertoire of known olfactory receptor (OR) enhancers and discovered unexpected rules of their dynamics: OR genes and their enhancers are most accessible during early differentiation. Furthermore, we revealed the dynamic spatial relationship between ORs and enhancers behind stepwise OR expression. These findings offer valuable insights into how 3D connectivity of ORs and enhancers dynamically orchestrate the 'one neuron-one receptor' selection process.


Assuntos
Cromatina , Elementos Facilitadores Genéticos , Perfilação da Expressão Gênica , Neurônios Receptores Olfatórios , Receptores Odorantes , Análise de Célula Única , Animais , Neurônios Receptores Olfatórios/metabolismo , Análise de Célula Única/métodos , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Camundongos , Perfilação da Expressão Gênica/métodos , Cromatina/genética , Cromatina/metabolismo , Genoma , Transcriptoma , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
18.
Int J Biol Macromol ; 268(Pt 1): 131503, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38663697

RESUMO

Herbivorous insects utilize intricate olfactory mechanisms to locate food plants. The chemical communication of insect-plant in primitive lineage offers insights into evolutionary milestones of divergent olfactory modalities. Here, we focus on a system endemic to the Qinghai-Tibetan Plateau to unravel the chemical and molecular basis of food preference in ancestral Lepidoptera. We conducted volatile profiling, neural electrophysiology, and chemotaxis assays with a panel of host plant organs to identify attractants for Himalaya ghost moth Thitarodes xiaojinensis larvae, the primitive host of medicinal Ophiocordyceps sinensis fungus. Using a DREAM approach based on odorant induced transcriptomes and subsequent deorphanization tests, we elucidated the odorant receptors responsible for coding bioactive volatiles. Contrary to allocation signals in most plant-feeding insects, T. xiaojinensis larvae utilize tricosane from the bulbil as the main attractant for locating native host plant. We deorphanized a TxiaOR17b, an indispensable odorant receptor resulting from tandem duplication of OR17, for transducing olfactory signals in response to tricosane. The discovery of this ligand-receptor pair suggests a survival strategy based on food location via olfaction in ancestral Lepidoptera, which synchronizes both plant asexual reproduction and peak hatch periods of insect larvae.


Assuntos
Larva , Mariposas , Receptores Odorantes , Animais , Mariposas/fisiologia , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Olfato/fisiologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/química , Filogenia , Quimiotaxia , Álcoois Graxos/farmacologia , Álcoois Graxos/química
19.
Pestic Biochem Physiol ; 201: 105861, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685215

RESUMO

Tribolium castaneum is a worldwide pest of stored grain that mainly damages flour, and not only causes serious loss of flour quality but also leads to deterioration of flour quality. Chemical detection plays a key role in insect behavior, and the role of odorant-binding proteins (OBPs) in insect chemical detection has been widely studied. OBPs can interact with small molecule compounds and thereby modulate variation in insecticide susceptibility in insects. In this study, a total of 65 small molecule compounds are selected to investigate the bound effect with TcOBP C12. The molecular docking results showed that ß-caryophyllene, (-)-catechin, butylated hydroxytoluene, diphenyl phthalate and quercetin were the top five compounds, with docking binding energies of -6.11, -5.25, -5.09, -5.05, and - 5.03 Kcal/mol, respectively. Molecular dynamics analysis indicated that odorant binding protein C12 (TcOBP C12) exhibited high binding affinity to all five tested chemical ligands, evidenced by fluorescence quenching assay in vitro. In addition, the contact toxicity assay results suggested that these chemical agents caused a dose-dependent increase in mortality rate for T. castaneum adults. The TcOBP C12 gene was upregulated >2 times after a 24-h exposure, indicating that OBP C12 may play an important role for T. castaneum in response to these chemical agents. In conclusion, our results provide a theoretical basis for future insecticide experiments and pest management.


Assuntos
Proteínas de Insetos , Simulação de Acoplamento Molecular , Receptores Odorantes , Tribolium , Animais , Tribolium/efeitos dos fármacos , Tribolium/metabolismo , Receptores Odorantes/metabolismo , Receptores Odorantes/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/química , Inseticidas/farmacologia , Inseticidas/toxicidade , Sesquiterpenos Policíclicos/farmacologia , Simulação de Dinâmica Molecular
20.
Pestic Biochem Physiol ; 201: 105856, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685238

RESUMO

Plutella xylostella is an important pest showing resistance to various chemical pesticides, development of botanical pesticides is an effective strategy to resolve above problem and decrease utilization of chemical pesticides. Previous study showed that 2,3-dimethyl-6-(1-hydroxy)-pyrazine has significant repellent activity to P. xylostella adult which mainly effect to the olfactory system, however the molecular targets and mechanism are still unclear. Based on the RNA-Seq and RT-qPCR data, eight ORs (Odorant receptor) in P. xylostella were selected as candidate targets response to repellent activity of 2,3-dimethyl-6-(1-hydroxy)-pyrazine. Here, most of the ORs in P. xylostella were clustered into three branches, which showed similar functions such as recognition, feeding, and oviposition. PxylOR29, PxylOR31, and PxylOR46 were identified as the potential molecular targets based on the results of repellent activity and EAG response tests to the adults which have been injected with dsRNA, respectively. Additionally, the three ORs were higher expressed in antenna of P. xylostella, followed by those in the head segment. Furthermore, it was found that the bindings between these three ORs and 2,3-dimethyl-6-(1-hydroxy)-pyrazine mainly depend on the hydrophobic effect of active cavities, and the binding to PxylOR31 was more stabler and easier with an energy of -16.34 kcal/mol, together with the π-π T-shaped interaction at PHE195 site. These findings pave the way for the complete understanding of pyrazine repellent mechanisms.


Assuntos
Repelentes de Insetos , Mariposas , Pirazinas , Receptores Odorantes , Animais , Receptores Odorantes/metabolismo , Receptores Odorantes/genética , Pirazinas/farmacologia , Repelentes de Insetos/farmacologia , Mariposas/efeitos dos fármacos , Mariposas/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética
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