Complementary expansions and contractions of the odorant, gustatory, and ionotropic receptor gene families in arthropods

AbstractThe ability of small secretory microvesicles known as exosomes to influence neuronal and glial function via their microRNA (miRNA) cargo has positioned them as a novel and effective method of cell-to-cell communication. However, little is known about the role of exosome-secreted miRNAs in the regulation of glutamate receptor gene expression and their relevance for schizophrenia (SCZ) and bipolar disorder (BD). Using mature miRNA profiling and quantitative real-time PCR (qRT-PCR) in the orbitofrontal cortex (OFC) of SCZ (N = 29; 20 male and 9 female), BD (N = 26; 12 male and 14 female), and unaffected control (N = 25; 21 male and 4 female) subjects, we uncovered that miR-223, an exosome-secreted miRNA that targets glutamate receptors, was increased at the mature miRNA level in the OFC of SCZ and BD patients with positive history of psychosis at the time of death and was inversely associated with deficits in the expression of its targets glutamate ionotropic receptor NMDA-type subunit 2B (GRIN2B) and glutamate ionotropic receptor AMPA-type subunit 2 (GRIA2). Furthermore, changes in miR-223 levels in the OFC were positively and negatively correlated with inflammatory and GABAergic gene expression, respectively. Moreover, miR-223 was found to be enriched in astrocytes and secreted via exosomes, and antipsychotics were shown to control its cellular and exosomal localization in a cell-specific manner. Furthermore, addition of astrocytic exosomes in neuronal cultures resulted in a significant increase in miR-223 expression and a notable reduction in Grin2b and Gria2 mRNA levels, which was strongly inversely associated with miR-223 expression. Lastly, inhibition of astrocytic miR-223 abrogated the exosomal-mediated reduction in neuronal Grin2b expression. Taken together, our results demonstrate that the exosomal secretion of a psychosis-altered and glial-enriched miRNA that controls neuronal gene expression is regulated by antipsychotics.

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Evolutionary relationships of the Tas2r receptor gene families in mouse and human

Physiological Genomics ◽

10.1152/physiolgenomics.00060.2003 ◽

2003 ◽

Vol 14 (1) ◽

pp. 73-82 ◽

Cited By ~ 60

Author(s):

Caroline Conte ◽

Martin Ebeling ◽

Anne Marcuz ◽

Patrick Nef ◽

Pedro J. Andres-Barquin

Keyword(s):

Bitter Taste ◽

Phylogenetic Analyses ◽

Receptor Gene ◽

Taste Receptor ◽

Gene Families ◽

Water Soluble ◽

Taste Perception ◽

Molecular Events ◽

Human Genomes ◽

Species Specific

The early molecular events in the perception of bitter taste start with the binding of specific water-soluble molecules to G protein-coupled receptors (GPCRs) encoded by the Tas2r family of taste receptor genes. The identification of the complete TAS2R receptor family repertoire in mouse and a comparative study of the Tas2r gene families in mouse and human might help to better understand bitter taste perception. We have identified, cloned, and characterized 13 new mouse Tas2r sequences, 9 of which encode putative functional bitter taste receptors. The encoded proteins are between 293 and 333 amino acids long and share between 18% and 54% sequence identity with other mouse TAS2R proteins. Including the 13 sequences identified, the mouse Tas2r family contains ∼30% more genes and 60% fewer pseudogenes than the human TAS2R family. Sequence and phylogenetic analyses of the proteins encoded by all mouse and human Tas2r genes indicate that TAS2R proteins present a lower degree of sequence conservation in mouse than in human and suggest a classification in five groups that may reflect a specialization in their functional activity to detect bitter compounds. Tas2r genes are organized in clusters in both mouse and human genomes, and an analysis of these clusters and phylogenetic analyses indicates that the five TAS2R protein groups were present prior to the divergence of the primate and rodent lineages. However, differences in subsequent evolutionary processes, including local duplications, interchromosomal duplications, divergence, and deletions, gave rise to species-specific sequences and shaped the diversity of the current TAS2R receptor families during mouse and human evolution.

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Molecular Evolution of the Major Arthropod Chemoreceptor Gene Families

Annual Review of Entomology ◽

10.1146/annurev-ento-020117-043322 ◽

2019 ◽

Vol 64 (1) ◽

pp. 227-242 ◽

Cited By ~ 50

Author(s):

Hugh M. Robertson

Keyword(s):

Molecular Evolution ◽

Odorant Receptor ◽

Gene Families ◽

Gene Family Evolution ◽

Gustatory Receptor ◽

Ionotropic Receptor ◽

Closely Related Species ◽

Evolutionary Origins ◽

Ligand Identification ◽

Receptor Family

The evolutionary origins of the three major families of chemoreceptors in arthropods—the odorant receptor (OR), gustatory receptor (GR), and ionotropic receptor (IR) families—occurred at the base of the Insecta, Animalia, and Protostomia, respectively. Comparison of receptor family sizes across arthropods reveals a generally positive correlation with their widely disparate complexity of chemical ecology. Closely related species reveal the ongoing processes of gene family evolution, including gene duplication, divergence, pseudogenization, and loss, that mediate these larger patterns. Sets of paralogous receptors within species reveal positive selection on amino acids in regions likely to contribute to ligand binding and specificity. Ligands of many ORs and some GRs and IRs have been identified; however, ligand identification for many more chemoreceptors is needed, as are structures for the OR/GR superfamily, to improve our understanding of the molecular evolution of these ecologically important receptors in arthropods.

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A Polyclonal T Cell Repertoire of V-Alpha and V-Beta T Cell Receptor Gene Families in Intrathyroidal T Lymphocytes of Graves' Disease Patients

Scandinavian Journal of Immunology ◽

10.1111/j.1365-3083.1995.tb03546.x ◽

1995 ◽

Vol 41 (2) ◽

pp. 141-147 ◽

Cited By ~ 8

Author(s):

E. CASO-PELAEZ ◽

A. M. McGREGOR ◽

J. P. BANGA

Keyword(s):

T Cell ◽

T Cell Receptor ◽

Receptor Gene ◽

Gene Families ◽

Cell Receptor ◽

Graves Disease ◽

T Cell Repertoire ◽

Cell Repertoire ◽

T Cell Receptor Gene ◽

Cell Receptor Gene

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Chemosensory Transduction in Arthropods

The Oxford Handbook of Invertebrate Neurobiology ◽

10.1093/oxfordhb/9780190456757.013.15 ◽

2017 ◽

pp. 344-366 ◽

Cited By ~ 1

Author(s):

Monika Stengl

Keyword(s):

Transient Receptor Potential ◽

Receptor Gene ◽

Olfactory Receptors ◽

Receptor Potential ◽

Gene Families ◽

Electrophysiological Studies ◽

Chemosensory Transduction ◽

Dependent Signal ◽

Transient Receptor ◽

Species Specific

Reception of chemicals via olfaction and gustation are prerequisites to find, distinguish, and recognize food and mates and to avoid dangers. Several receptor gene superfamilies are employed in arthropod chemosensation: inverse 7-transmembrane (7-TM) gustatory and olfactory receptors (GRs, ORs), 3-TM ionotropic glutamate-related receptors (IRs), receptor-guanylyl cyclases, transient receptor potential ion channels, and epithelial sodium channels. Some of these receptor gene families have ancient origins and expanded in several taxa, producing very large, variant gene families adapted to the respectively relevant odor ligands in species-specific environments. Biochemical and electrophysiological studies in situ as well as molecular genetics found evidence for G-protein-dependent signal transduction cascades for ORs, GRs, and IRs, suggesting that signal amplification is paramount for chemical senses. In contrast, heterologous expression studies argued for primarily ionotropic transduction as a prerequisite to interstimulus intervals in the range of microseconds.

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