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F1000Research 2022Bovine congestive heart failure (BCHF) has become increasingly prevalent among feedlot cattle in the Western Great Plains of North America with up to 7% mortality in...
BACKGROUND
Bovine congestive heart failure (BCHF) has become increasingly prevalent among feedlot cattle in the Western Great Plains of North America with up to 7% mortality in affected herds. BCHF is an untreatable complex condition involving pulmonary hypertension that culminates in right ventricular failure and death. Genes associated with BCHF in feedlot cattle have not been previously identified. Our aim was to search for genomic regions associated with this disease.
METHODS
A retrospective, matched case-control design with 102 clinical BCHF cases and their unaffected pen mates was used in a genome-wide association study. Paired nominal data from approximately 560,000 filtered single nucleotide polymorphisms (SNPs) were analyzed with McNemar's test.
RESULTS
Two independent genomic regions were identified as having the most significant association with BCHF: the arrestin domain-containing protein 3 gene ( ), and the nuclear factor IA gene ( , mid- -values, 1x10 and 2x10 , respectively). Animals with two copies of risk alleles at either gene were approximately eight-fold more likely to have BCHF than their matched pen mates with either one or zero risk alleles at both genes (CI = 3-17). Further, animals with two copies of risk alleles at both genes were 28-fold more likely to have BCHF than all others ( -value = 1×10 , CI = 4-206). A missense variant in (C182Y) represents a potential functional variant since the C182 codon is conserved among all other jawed vertebrate species observed. A two-SNP test with markers in both genes showed 29% of 273 BCHF cases had homozygous risk genotypes in both genes, compared to 2.5% in 198 similar unaffected feedlot cattle. This and other DNA tests may be useful for identifying feedlot animals with the highest risk for BCHF in the environments described here.
CONCLUSIONS
Although pathogenic roles for variants in the and genes are unknown, their discovery facilitates classifying animals by genetic risk and allows cattle producers to make informed decisions for selective breeding and animal health management.
Topics: Animals; Cattle; Arrestins; Case-Control Studies; Cattle Diseases; Genetic Predisposition to Disease; Genome-Wide Association Study; Heart Failure; NFI Transcription Factors; Polymorphism, Single Nucleotide; Retrospective Studies
PubMed: 38680232
DOI: 10.12688/f1000research.109488.2 -
Biomolecules Mar 2024This study assessed the suitability of the complementarity-determining region 2 (CDR2) of the nanobody (Nb) as a template for the derivation of nanobody-derived peptides...
Computational Modeling and Characterization of Peptides Derived from Nanobody Complementary-Determining Region 2 (CDR2) Targeting Active-State Conformation of the β-Adrenergic Receptor (βAR).
This study assessed the suitability of the complementarity-determining region 2 (CDR2) of the nanobody (Nb) as a template for the derivation of nanobody-derived peptides (NDPs) targeting active-state β-adrenergic receptor (βAR) conformation. Sequences of conformationally selective Nbs favoring the agonist-occupied βAR were initially analyzed by the informational spectrum method (ISM). The derived NDPs in complex with βAR were subjected to protein-peptide docking, molecular dynamics (MD) simulations, and metadynamics-based free-energy binding calculations. Computational analyses identified a 25-amino-acid-long CDR2-NDP of Nb71, designated P4, which exhibited the following binding free-energy for the formation of the βAR:P4 complex (ΔG = -6.8 ± 0.8 kcal/mol or a Ki = 16.5 μM at 310 K) and mapped the βAR:P4 amino acid interaction network. In vitro characterization showed that P4 (i) can cross the plasma membrane, (ii) reduces the maximum isoproterenol-induced cAMP level by approximately 40% and the isoproterenol potency by up to 20-fold at micromolar concentration, (iii) has a very low affinity to interact with unstimulated βAR in the cAMP assay, and (iv) cannot reduce the efficacy and potency of the isoproterenol-mediated βAR/β-arrestin-2 interaction in the BRET-based recruitment assay. In summary, the CDR2-NDP, P4, binds preferentially to agonist-activated βAR and disrupts Gαs-mediated signaling.
Topics: Humans; Amino Acid Sequence; Complementarity Determining Regions; Cyclic AMP; Molecular Docking Simulation; Molecular Dynamics Simulation; Peptides; Protein Binding; Protein Conformation; Receptors, Adrenergic, beta-2; Single-Domain Antibodies
PubMed: 38672440
DOI: 10.3390/biom14040423 -
Gene Aug 2024The study is based on the complexity of Insulin like growth factor receptor (IGF1R) signaling and its regulation by noncoding RNAs (ncRNAs). IGF1R signaling is an...
The study is based on the complexity of Insulin like growth factor receptor (IGF1R) signaling and its regulation by noncoding RNAs (ncRNAs). IGF1R signaling is an important cascade in Alzheimer's disease (AD); however, its regulation and roles are poorly understood. Due to the presence of β-arrestin and GPCR Receptor Kinase binding sites, this protein has been termed a 'functional hybrid', as it can take part in both kinase and GPCR signaling pathways, further adding to its complexity. The objective of this study is to understand the underlying ncRNA regulation controlling IGF1R and GPCRs in AD to find commonalities in the network. We found through data mining that 45 GPCRs were reportedly deregulated in AD and built clusters based on GO/KEGG pathways to show shared functionality with IGF1R. Eight miRs were further discovered that could coregulate IGF1R and GPCRs. We validated their expression in an AD cell model and probed for common lncRNAs downstream that could regulate these miRs. Seven such candidates were identified and further validated. A combined network comprising IGF1R with nine GPCRs, eight miRs, and seven lncRNAs was created to visualize the interconnectivity within pathways. Betweenness centrality analysis showed a cluster of NEAT1, hsa-miR-15a-5p, hsa-miR-16-5p, and IGF1R to be crucial form a competitive endogenous RNA-based (ceRNA) tetrad that could relay information within the network, which was further validated by cell-based studies. NEAT1 emerged as a master regulator that could alter the levels of IGF1R and associated GPCRs. This combined bioinformatics and experimental study for the first time explored the regulation of IGF1R through ncRNAs from the perspective of neurodegeneration.
Topics: Alzheimer Disease; Humans; Receptor, IGF Type 1; RNA, Long Noncoding; MicroRNAs; Signal Transduction; Receptors, G-Protein-Coupled; Gene Expression Regulation; Receptors, Somatomedin; Gene Regulatory Networks
PubMed: 38670398
DOI: 10.1016/j.gene.2024.148503 -
Frontiers in Molecular Biosciences 2024
PubMed: 38660374
DOI: 10.3389/fmolb.2024.1403161 -
BioRxiv : the Preprint Server For... Apr 2024The dopamine D1 receptor (D1R) has fundamental roles in voluntary movement and memory and is a validated drug target for neurodegenerative and neuropsychiatric...
The dopamine D1 receptor (D1R) has fundamental roles in voluntary movement and memory and is a validated drug target for neurodegenerative and neuropsychiatric disorders. However, previously developed D1R selective agonists possess a catechol moiety which displays poor pharmacokinetic properties. The first selective non-catechol D1R agonists were recently discovered and unexpectedly many of these ligands showed G protein biased signaling. Here, we investigate both catechol and non-catechol D1R agonists to validate potential biased signaling and examine if this impacts agonist-induced D1R endocytosis. We determined that most, but not all, non-catechol agonists display G protein biased signaling at the D1R and have reduced or absent Beta-arrestin recruitment. A notable exception was compound (Cmpd) 19, a non-catechol agonist with full efficacy at both D1R-G protein or D1R Beta-arrestin pathways. In addition, the catechol ligand A-77636 was a highly potent, super agonist for D1R Beta-arrestin activity. When examined for agonist-induced D1R endocytosis, balanced agonists SKF-81297 and Cmpd 19 induced robust D1R endocytosis while the G protein biased agonists did not. The Beta-arrestin super agonist, A-77636, showed significantly increased D1R endocytosis. Moreover, Beta-arrestin recruitment efficacy of tested agonists strongly correlated with total D1R endocytosis. Taken together, these results indicate the degree of D1R signaling functional selectivity profoundly impacts D1R endocytosis regardless of pharmacophore. The range of functional selectivity of these D1R agonists will provide valuable tools to further investigate D1R signaling, trafficking and therapeutic potential.
PubMed: 38659786
DOI: 10.1101/2024.04.15.589637 -
The Journal of Physical Chemistry. B May 2024The chemokine receptor CXCR4 is a critical target for the treatment of several cancer types and HIV-1 infections. While orthosteric and allosteric modulators have been...
The chemokine receptor CXCR4 is a critical target for the treatment of several cancer types and HIV-1 infections. While orthosteric and allosteric modulators have been developed targeting its extracellular or transmembrane regions, the intramembrane region of CXCR4 may also include allosteric binding sites suitable for the development of allosteric drugs. To investigate this, we apply the Gaussian Network Model (GNM) to the monomeric and dimeric forms of CXCR4 to identify residues essential for its local and global motions located in the hinge regions of the protein. Residue interaction network (RIN) analysis suggests hub residues that participate in allosteric communication throughout the receptor. Mutual residues from the network models reside in regions with a high capacity to alter receptor dynamics upon ligand binding. We then investigate the druggability of these potential allosteric regions using the site identification by ligand competitive saturation (SILCS) approach, revealing two putative allosteric sites on the monomer and three on the homodimer. Two screening campaigns with Glide and SILCS-Monte Carlo docking using FDA-approved drugs suggest 20 putative hit compounds including antifungal drugs, anticancer agents, HIV protease inhibitors, and antimalarial drugs. assays considering mAB 12G5 and CXCL12 demonstrate both positive and negative allosteric activities of these compounds, supporting our computational approach. However, functional assays based on the recruitment of β-arrestin to CXCR4 do not show significant agonism and antagonism at a single compound concentration. The present computational pipeline brings a new perspective to computer-aided drug design by combining conformational dynamics based on network analysis and cosolvent analysis based on the SILCS technology to identify putative allosteric binding sites using CXCR4 as a showcase.
Topics: Receptors, CXCR4; Allosteric Site; Ligands; Humans; Molecular Docking Simulation; Monte Carlo Method; Allosteric Regulation
PubMed: 38647430
DOI: 10.1021/acs.jpcb.4c00925 -
American Journal of Physiology. Cell... Jun 2024G protein-coupled receptors (GPCRs) are ubiquitously expressed cell surface receptors that mediate numerous physiological responses and are highly druggable. Upon... (Review)
Review
G protein-coupled receptors (GPCRs) are ubiquitously expressed cell surface receptors that mediate numerous physiological responses and are highly druggable. Upon activation, GPCRs rapidly couple to heterotrimeric G proteins and are then phosphorylated and internalized from the cell surface. Recent studies indicate that GPCRs not only localize at the plasma membrane but also exist in intracellular compartments where they are competent to signal. Intracellular signaling by GPCRs is best described to occur at endosomes. Several studies have elegantly documented endosomal GPCR-G protein and GPCR-β-arrestin signaling. Besides phosphorylation, GPCRs are also posttranslationally modified with ubiquitin. GPCR ubiquitination has been studied mainly in the context of receptor endosomal-lysosomal trafficking. However, new studies indicate that ubiquitination of endogenous GPCRs expressed in endothelial cells initiates the assembly of an intracellular p38 mitogen-activated kinase signaling complex that promotes inflammatory responses from endosomes. In this mini-review, we discuss emerging discoveries that provide critical insights into the function of ubiquitination in regulating GPCR inflammatory signaling at endosomes.
Topics: Endosomes; Humans; Receptors, G-Protein-Coupled; Signal Transduction; Animals; Ubiquitination; Inflammation; Ubiquitin; Phosphorylation
PubMed: 38646783
DOI: 10.1152/ajpcell.00161.2024 -
BioRxiv : the Preprint Server For... Apr 2024Alcohol use disorders (AUDs) impose an enormous societal and financial burden, and world-wide, alcohol misuse is the 7 leading cause of premature death. Despite this,...
Alcohol use disorders (AUDs) impose an enormous societal and financial burden, and world-wide, alcohol misuse is the 7 leading cause of premature death. Despite this, there are currently only 3 FDA approved pharmacological treatments for the treatment of AUDs in the United States. The neurotensin (Nts) system has long been implicated in modulating behaviors associated with alcohol misuse. Recently, a novel compound, SBI-553, that biases the action of Nts receptor 1 (NTSR1) activation, has shown promise in preclinical models of psychostimulant misuse. Here we investigate the efficacy of this compound to alter ethanol-mediated behaviors in a comprehensive battery of experiments assessing ethanol consumption, behavioral responses to ethanol, sensitivity to ethanol, and ethanol metabolism. Additionally, we investigated behavior in avoidance and cognitive assays to monitor potential side effects of SBI-553. We find that SBI-553 reduces binge-like ethanol consumption in mice without altering avoidance behavior or novel object recognition. We also observe sex-dependent differences in physiological responses to sequential ethanol injections in mice. In rats, we show that SBI-553 attenuates sensitivity to the interoceptive effects of ethanol (using a Pavlovian drug discrimination task). Our data suggest that targeting NTSR1 signaling may be promising to attenuate alcohol misuse, and adds to a body of literature that suggests NTSR1 may be a common downstream target involved in the psychoactive effects of multiple reinforcing substances.
PubMed: 38645173
DOI: 10.1101/2024.04.10.588903 -
Biochemical Pharmacology Apr 2024Two recently discovered DRD2 mutations, c.634A > T, p.Ile212Phe and c.1121T > G, p.Met374Arg, cause hyperkinetic movement disorders that have overlapping features...
Two recently discovered DRD2 mutations, c.634A > T, p.Ile212Phe and c.1121T > G, p.Met374Arg, cause hyperkinetic movement disorders that have overlapping features but apparently differ in severity. The two known carriers of the Met374Arg variant had early childhood disease onset and more severe motor, cognitive, and neuropsychiatric deficits than any known carriers of the Ile212Phe variant, whose symptoms were first apparent in adolescence. Here, we evaluated if differences in the function of the two variants in cultured cells could explain differing pathogenicity. Both variants were expressed less abundantly than the wild type receptor and exhibited loss of agonist-induced arrestin binding, but differences in expression and arrestin binding between the variants were minor. Basal and agonist-induced activation of heterotrimeric G proteins, however, showed clear differences; agonists were generally more potent at Met374Arg than at the Ile212Phe or wild type variants. Furthermore, all Gα subtypes tested were constitutively activated more by Met374Arg than by Ile212Phe. Met374Arg produced greater constitutive inhibition of cyclic AMP accumulation than Ile212Phe or the wild type D2 receptor. Met374Arg and Ile212Phe were more sensitive to thermal inactivation than the wild type D2 receptor, as reported for other constitutively active receptors, but Ile212Phe was affected more than Met374Arg. Additional pharmacological characterization suggested that the mutations differentially affect the shape of the agonist binding pocket and the potency of dopamine, norepinephrine, and tyramine. Molecular dynamics simulations provided a structural rationale for enhanced constitutive activation and agonist potency. Enhanced constitutive and agonist-induced G protein-mediated signaling likely contributes to the pathogenicity of these novel variants.
PubMed: 38643909
DOI: 10.1016/j.bcp.2024.116228 -
Trends in Biochemical Sciences Jun 2024G protein-coupled receptors (GPCRs) located at the cell surface bind extracellular ligands and convey intracellular signals via activation of heterotrimeric G proteins.... (Review)
Review
G protein-coupled receptors (GPCRs) located at the cell surface bind extracellular ligands and convey intracellular signals via activation of heterotrimeric G proteins. Traditionally, G protein signaling was viewed to occur exclusively at this subcellular region followed by rapid desensitization facilitated by β-arrestin (βarr)-mediated G protein uncoupling and receptor internalization. However, emerging evidence over the past 15 years suggests that these βarr-mediated events do not necessarily terminate receptor signaling and that some GPCRs continue to activate G proteins after having been internalized into endosomes. Here, we review the recently elucidated mechanistic basis underlying endosomal GPCR signaling and discuss physiological implications and pharmacological targeting of this newly appreciated signaling mode.
Topics: Endosomes; Signal Transduction; Receptors, G-Protein-Coupled; Humans; Animals; beta-Arrestins
PubMed: 38643023
DOI: 10.1016/j.tibs.2024.03.006