Dataset Information

Isolation and characterization of alternatively spliced variants of the mouse sigma1 receptor gene, Sigmar1.

ABSTRACT: The sigma1 receptor acts as a chaperone at the endoplasmic reticulum, associates with multiple proteins in various cellular systems, and involves in a number of diseases, such as addiction, pain, cancer and psychiatric disorders. The sigma1 receptor is encoded by the single copy SIGMAR1 gene. The current study identifies five alternatively spliced variants of the mouse sigma1 receptor gene using a polymerase chain reaction cloning approach. All the splice variants are generated by exon skipping or alternative 3' or 5' splicing, producing the truncated sigma1 receptor. Similar alternative splicing has been observed in the human SIGMAR1 gene based on the molecular cloning or genome sequence prediction, suggesting conservation of alternative splicing of SIGMAR1 gene. Using quantitative polymerase chain reactions, we demonstrate differential expression of several splice variants in mouse tissues and brain regions. When expressed in HEK293 cells, all the splice variants fail to bind sigma ligands, implicating that each truncated region in these splice variants is important for ligand binding. However, co-immunoprecipitation (Co-IP) study in HEK293 cells co-transfected with tagged constructs reveals that all the splice variants maintain their ability to physically associate with a mu opioid receptor (mMOR-1), providing useful information to correlate the motifs/sequences necessary for their physical association. Furthermore, a competition Co-IP study showed that all the variants can disrupt in a dose-dependent manner the dimerization of the original sigma1 receptor with mMOR-1, suggesting a potential dominant negative function and providing significant insights into their function.

SUBMITTER: Pan L

PROVIDER: S-EPMC5370144 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Isolation and characterization of alternatively spliced variants of the mouse sigma1 receptor gene, Sigmar1.

Pan Ling L Pasternak David A DA Xu Jin J Xu Mingming M Lu Zhigang Z Pasternak Gavril W GW Pan Ying-Xian YX

PloS one 20170328 3

The sigma1 receptor acts as a chaperone at the endoplasmic reticulum, associates with multiple proteins in various cellular systems, and involves in a number of diseases, such as addiction, pain, cancer and psychiatric disorders. The sigma1 receptor is encoded by the single copy SIGMAR1 gene. The current study identifies five alternatively spliced variants of the mouse sigma1 receptor gene using a polymerase chain reaction cloning approach. All the splice variants are generated by exon skipping ...[more]

PMID: 28350844

Similar Datasets

Project description:Dopamine is an important neurotransmitter in the central nervous system of both Drosophila and mammals. Despite the evolutionary distance, functional parallels exist between the fly and mammalian dopaminergic systems, with both playing roles in modulating locomotor activity, sexual function, and the response to drugs of abuse. In mammals, dopamine exerts its effects through either dopamine 1-like (D1-like) or D2-like G protein-coupled receptors. Although pharmacologic data suggest the presence of both receptor subtypes in insects, only cDNAs encoding D1-like proteins have been isolated previously. Here we report the cloning and characterization of a newly discovered Drosophila dopamine receptor. Sequence analysis reveals that this putative protein shares highest homology with known mammalian dopamine 2-like receptors. Eight isoforms of the Drosophila D2-like receptor (DD2R) transcript have been identified, each the result of alternative splicing. The encoded heptahelical receptors range in size from 461 to 606 aa, with variability in the length and sequence of the third intracellular loop. Pharmacologic assessment of three DD2R isoforms, DD2R-606, DD2R-506, and DD2R-461, revealed that among the endogenous biogenic amines, dopamine is most potent at each receptor. As established for mammalian D2-like receptors, stimulation of the Drosophila homologs with dopamine triggers pertussis toxin-sensitive Gi/o-mediated signaling. The D2-like receptor agonist, bromocriptine, has nanomolar potency at DD2R-606, -506, and -461, whereas multiple D2-like receptor antagonists (as established with mammalian receptors) have markedly reduced if any affinity when assessed at the fly receptor isoforms. The isolation of cDNAs encoding Drosophila D2-like receptors extends the range of apparent parallels between the dopaminergic system in flies and mammals. Pharmacologic and genetic manipulation of the DD2Rs will provide the opportunity to better define the physiologic role of these proteins in vivo and further explore the utility of invertebrates as a model system for understanding dopaminergic function in higher organisms.

Project description:BackgroundThe long-term effects of psychotropic drugs are associated with the reversal of disease-related alterations through the reorganization and normalization of neuronal connections. Molecular factors that trigger drug-induced brain plasticity remain only partly understood. Doublecortin-like kinase 1 (Dclk1) possesses microtubule-polymerizing activity during synaptic plasticity and neurogenesis. However, the Dclk1 gene shows a complex profile of transcriptional regulation, with two alternative promoters and exon splicing patterns that suggest the expression of multiple isoforms with different kinase activities.ResultsHere, we applied next-generation sequencing to analyze changes in the expression of Dclk1 gene isoforms in the brain in response to several psychoactive drugs with diverse pharmacological mechanisms of action. We used bioinformatics tools to define the range and levels of Dclk1 transcriptional regulation in the mouse nucleus accumbens and prefrontal cortex. We also sought to investigate the presence of DCLK1-derived peptides using mass spectrometry. We detected 15 transcripts expressed from the Dclk1 locus (FPKM > 1), including 2 drug-regulated variants (fold change > 2). Drugs that act on serotonin receptors (5-HT2A/C) regulate a subset of Dclk1 isoforms in a brain-region-specific manner. The strongest influence was observed for the mianserin-induced expression of an isoform with intron retention. The drug-activated expression of novel alternative Dclk1 isoforms was validated using qPCR. The drug-regulated isoform contains genetic variants of DCLK1 that have been previously associated with schizophrenia and hyperactivity disorder in humans. We identified a short peptide that might originate from the novel DCLK1 protein product. Moreover, protein domains encoded by the regulated variant indicate their potential involvement in the negative regulation of the canonical DCLK1 protein.ConclusionsIn summary, we identified novel isoforms of the neuroplasticity-related gene Dclk1 that are expressed in the brain in response to psychotropic drug treatments.

Dataset Information

Isolation and characterization of alternatively spliced variants of the mouse sigma1 receptor gene, Sigmar1.

Publications

Isolation and characterization of alternatively spliced variants of the mouse sigma1 receptor gene, Sigmar1.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets