Cyclic ADP ribose isomers: Production, chemical structures, and immune signaling.

Cyclic adenosine diphosphate (ADP)-ribose (cADPR) isomers are signaling molecules produced by bacterial and plant Toll/interleukin-1 receptor (TIR) domains via nicotinamide adenine dinucleotide (oxidized form) (NAD+) hydrolysis. We show that v-cADPR (2'cADPR) and v2-cADPR (3'cADPR) isomers are cyclized by O-glycosidic bond formation between the ribose moieties in ADPR. Structures of 2'cADPR-producing TIR domains reveal conformational changes that lead to an active assembly that resembles those of Toll-like receptor adaptor TIR domains. Mutagenesis reveals a conserved tryptophan that is essential for cyclization. We show that 3'cADPR is an activator of ThsA effector proteins from the bacterial antiphage defense system termed Thoeris and a suppressor of plant immunity when produced by the effector HopAM1. Collectively, our results reveal the molecular basis of cADPR isomer production and establish 3'cADPR in bacteria as an antiviral and plant immunity-suppressing signaling molecule.

Downregulation of the Cd38-Cyclic ADP-Ribose Signaling in Cardiomyocytes by Intermittent Hypoxia via Pten Upregulation.

Sleep apnea syndrome (SAS) is characterized by recurrent episodes of oxygen desaturation and reoxygenation (intermittent hypoxia, IH), and it is a risk factor for cardiovascular disease (CVD) and insulin resistance/type 2 diabetes. However, the mechanisms linking IH stress and CVD remain elusive. We exposed rat H9c2 and mouse P19.CL6 cardiomyocytes to experimental IH or normoxia for 24 h to analyze the mRNA expression of the components of Cd38-cyclic ADP-ribose (cADPR) signaling. We found that the mRNA levels of cluster of differentiation 38 (Cd38), type 2 ryanodine receptor (Ryr2), and FK506-binding protein 12.6 (Fkbp12.6) in H9c2 and P19.CL6 cardiomyocytes were significantly decreased by IH, whereas the promoter activities of these genes were not decreased. By contrast, the expression of phosphatase and tensin homolog deleted from chromosome 10 (Pten) was upregulated in IH-treated cells. The small interfering RNA for Pten (siPten) and a non-specific control RNA were introduced into the H9c2 cells. The IH-induced downregulation of Cd38, Ryr2, and Fkbp12.6 was abolished by the introduction of the siPten, but not by the control RNA. These results indicate that IH stress upregulated the Pten in cardiomyocytes, resulting in the decreased mRNA levels of Cd38, Ryr2, and Fkbp12.6, leading to the inhibition of cardiomyocyte functions in SAS patients.

BST1 regulates nicotinamide riboside metabolism via its glycohydrolase and base-exchange activities.

Nicotinamide riboside (NR) is one of the orally bioavailable NAD+ precursors and has been demonstrated to exhibit beneficial effects against aging and aging-associated diseases. However, the metabolic pathway of NR in vivo is not yet fully understood. Here, we demonstrate that orally administered NR increases NAD+ level via two different pathways. In the early phase, NR was directly absorbed and contributed to NAD+ generation through the NR salvage pathway, while in the late phase, NR was hydrolyzed to nicotinamide (NAM) by bone marrow stromal cell antigen 1 (BST1), and was further metabolized by the gut microbiota to nicotinic acid, contributing to generate NAD+ through the Preiss-Handler pathway. Furthermore, we report BST1 has a base-exchange activity against both NR and nicotinic acid riboside (NAR) to generate NAR and NR, respectively, connecting amidated and deamidated pathways. Thus, we conclude that BST1 plays a dual role as glycohydrolase and base-exchange enzyme during oral NR supplementation.

CD157 signaling promotes survival of acute myeloid leukemia cells and modulates sensitivity to cytarabine through regulation of anti-apoptotic Mcl-1.

CD157/BST-1 (a member of the ADP-ribosyl cyclase family) is expressed at variable levels in 97% of patients with acute myeloid leukemia (AML), and is currently under investigation as a target for antibody-based immunotherapy. We used peripheral blood and bone marrow samples from patients with AML to analyse the impact of CD157-directed antibodies in AML survival and in response to cytarabine (AraC) ex vivo. The study was extended to the U937, THP1 and OCI-AML3 AML cell lines of which we engineered CD157-low versions by shRNA knockdown. CD157-targeting antibodies enhanced survival, decreased apoptosis and reduced AraC toxicity in AML blasts and cell lines. CD157 signaling activated the PI3K/AKT/mTOR and MAPK/ERK pathways and increased expression of Mcl-1 and Bcl-XL anti-apoptotic proteins, while decreasing expression of Bax pro-apoptotic protein, thus preventing Caspase-3 activation. The primary CD157-mediated anti-apoptotic mechanism was Bak sequestration by Mcl-1. Indeed, the Mcl-1-specific inhibitor S63845 restored apoptosis by disrupting the interaction of Mcl-1 with Bim and Bak and significantly increased AraC toxicity in CD157-high but not in CD157-low AML cells. This study provides a new role for CD157 in AML cell survival, and indicates a potential role of CD157 as a predictive marker of response to therapies exploiting Mcl-1 pharmacological inhibition.

Blending oxytocin and dopamine with everyday creativity.

Converging evidence suggests that oxytocin (OT) is associated with creative thinking (CT) and that release of OT depends on ADP ribosyl-cyclases (CD38 and CD157). Neural mechanisms of CT and OT show a strong association with dopaminergic (DA) pathways, yet the link between CT and CD38, CD157, dopamine receptor D2 (DRD2) and catechol-O-methyltransferase (COMT) peripheral gene expression remain inconclusive, thus limiting our understanding of the neurobiology of CT. To address this issue, two principal domains of CT, divergent thinking (AUT), were assessed. In men, both AUT is associated with gene expression of CD38, CD157, and their interaction CD38 × CD157. There were no significant associations for DA expression (DRD2, COMT, DRD2 × COMT) on both CT measures. However, analysis of the interactions of OT and DA systems reveal significant interactions for AUT in men. The full model explained a sizable 39% of the variance in females for the total CT score. The current findings suggest that OT and DA gene expression contributed significantly to cognition and CT phenotype. This provides the first empirical foundation of a more refined understanding of the molecular landscape of CT.

A Truncated TIR-NBS Protein TN10 Pairs with Two Clustered TIR-NBS-LRR Immune Receptors and Contributes to Plant Immunity in Arabidopsis.

The encoding genes of plant intracellular nucleotide-binding site (NBS) and leucine-rich repeat (LRR) domain receptors (NLRs) often exist in the form of a gene cluster. Several recent studies demonstrated that the truncated Toll/interleukin-1 receptor-NBS (TIR-NBS) proteins play important roles in immunity. In this study, we identified a large TN gene cluster on Arabidopsis ecotype Col-0 chromosome 1, which included nine TN genes, TN4 to TN12. Interestingly, this cluster also contained two typical TIR-NBS-LRR genes: At1g72840 and At1g72860 (hereinafter referred to as TNL40 and TNL60, respectively), which formed head-to-head genomic arrangement with TN4 to TN12. However, the functions of these TN and TNL genes in this cluster are still unknown. Here, we showed that the TIR domains of both TNL40 and TNL60 associated with TN10 specifically. Furthermore, both TNL40TIR and TNL60TIR induced cell death in Nicotiana tabacum leaves. Subcellular localization showed that TNL40 mainly localized in the cytoplasm, whereas TNL60 and TN10 localized in both the cytoplasm and nucleus. Additionally, the expression of TNL40, TNL60, and TN10 were co-regulated after inoculated with bacterial pathogens. Taken together, our study indicates that the truncated TIR-NBS protein TN10 associates with two clustered TNL immune receptors, and may work together in plant disease resistance.

Association of BST1 polymorphism with idiopathic restless legs syndrome in Chinese population.

BACKGROUND: Parkinson's disease (PD) and restless legs syndrome/Willis-Ekbom disease (RLS/WED) are both common movement disorders. Based on their clinical overlap, association studies of PD and RLS/WED have been conducted for many years. OBJECTIVE: To investigate whether or not the genetic risk factor of PD was also associated with RLS/WED. SUBJECTS AND METHODS: We included 102 idiopathic RLS/WED patients and 189 matched controls from southeast China. The clinical data included the International Restless Legs Syndrome Study Group Rating Scale, the subtypes of RLS/WED symptoms (painful or other discomfort), the comorbidities, the pregnancy history of female patients, the Hamilton Depression Scale (HAMD), and the Pittsburgh Sleep Quality Index (PSQI) questionnaire. Risk gene analysis between RLS/WED and control groups including 21 SNPs (single nucleotide polymorphisms) was conducted. Genotyping was done by Sanger sequencing. RESULTS: We found that rs4273468 polymorphism of BST1 gene increased the risk of idiopathic RLS/WED patients in southeastern Chinese population (P = <0.001, OR = 2.85, p = 0.019 after Bonferroni correction). Moreover, the haplotype of G-G (rs4698412-rs4273468) was significantly associated with Chinese RLS/WED patients (p = <0.001). CONCLUSION: BST1 may contribute to the development of RLS/WED. Further studies on larger cohorts are needed to confirm these findings.

Novel Associations of BST1 and LAMP3 With REM Sleep Behavior Disorder.

OBJECTIVE: To examine the role of genes identified through genome-wide association studies (GWASs) of Parkinson disease (PD) in the risk of isolated REM sleep behavior disorder (iRBD). METHODS: We fully sequenced 25 genes previously identified in GWASs of PD in a total of 1,039 patients with iRBD and 1,852 controls. The role of rare heterozygous variants in these genes was examined with burden tests. The contribution of biallelic variants was further tested. To examine the potential effect of rare nonsynonymous BST1 variants on the protein structure, we performed in silico structural analysis. Finally, we examined the association of common variants using logistic regression adjusted for age and sex. RESULTS: We found an association between rare heterozygous nonsynonymous variants in BST1 and iRBD (p = 0.0003 at coverage >50× and 0.0004 at >30×), driven mainly by 3 nonsynonymous variants (p.V85M, p.I101V, and p.V272M) found in 22 (1.2%) controls vs 2 (0.2%) patients. All 3 variants seem to be loss-of-function variants with a potential effect on the protein structure and stability. Rare noncoding heterozygous variants in LAMP3 were also associated with iRBD (p = 0.0006 at >30×). We found no association between rare heterozygous variants in the rest of genes and iRBD. Several carriers of biallelic variants were identified, yet there was no overrepresentation in iRBD. CONCLUSION: Our results suggest that rare coding variants in BST1 and rare noncoding variants in LAMP3 are associated with iRBD. Additional studies are required to replicate these results and to examine whether loss of function of BST1 could be a therapeutic target.

Distinct physical condition and social behavior phenotypes of CD157 and CD38 knockout mice during aging.

The ability of CD38 and CD157 to utilize nicotinamide adenine dinucleotide (NAD) has received much attention because the aging-induced elevation of CD38 expression plays a role in the senescence-related decline in NAD levels. Therefore, it is of interest to examine and compare the effects of age-associated changes on the general health and brain function impairment of Cd157 and Cd38 knockout (CD157 KO and CD38 KO) mice. The body weight and behaviors were measured in 8-week-old (young adult) or 12-month-old (middle-aged) male mice of both KO strains. The locomotor activity, anxiety-like behavior, and social behavior of the mice were measured in the open field and three-chamber tests. The middle-aged CD157 KO male mice gained more body weight than young adult KO mice, while little or no body weight gain was observed in the middle-aged CD38 KO mice. Middle-aged CD157 KO mice displayed increased anxiety-like behavior and decreased sociability and interaction compared with young adult KO mice. Middle-aged CD38 KO mice showed less anxiety and hyperactivity than CD157 KO mice, similar to young adult CD38 KO mice. The results reveal marked age-dependent changes in male CD157 KO mice but not in male CD38 KO mice. We discuss the distinct differences in aging effects from the perspective of inhibition of NAD metabolism in CD157 and CD38 KO mice, which may contribute to differential behavioral changes during aging.

Mitochondrial calcium drives clock gene-dependent activation of pyruvate dehydrogenase and of oxidative phosphorylation.

Regulation of metabolism is emerging as a major output of circadian clock circuitry in mammals. Accordingly, mitochondrial oxidative metabolism undergoes both in vivo and in vitro daily oscillatory activities. In a previous study we showed that both glycolysis and mitochondrial oxygen consumption display a similar time-resolved rhythmic activity in synchronized HepG2 cell cultures, which translates in overall bioenergetic changes as here documented by measurement of the ATP level. Treatment of synchronized cells with specific metabolic inhibitors unveiled pyruvate as a major source of reducing equivalents to the respiratory chain with its oxidation driven by the rhythmic (de)phosphorylation of pyruvate dehydrogenase. Further investigation enabled to causally link the autonomous cadenced mitochondrial respiration to a synchronous increase of the mitochondrial Ca2+. The rhythmic change of the mitochondrial respiration was dampened by inhibitors of the mitochondrial Ca2+ uniporter as well as of the ryanodine receptor Ca2+ channel or the ADPR cyclase, indicating that the mitochondrial Ca2+ influx originated from the ER store, likely at contact sites with the mitochondrial compartment. Notably, blockage of the mitochondrial Ca2+ influx resulted in deregulation of the expression of canonical clock genes such as BMALl1, CLOCK, NR1D1. All together our findings unveil a hitherto unexplored function of Ca2+-mediated signaling in time keeping the mitochondrial metabolism and in its feed-back modulation of the circadian clockwork.

ASSOCIATION BETWEEN DIABETICS AND INTESTINAL CANCER WITH THE RISK OF MUTATION IN CD38 GENE IN IRANIAN POPULATION.

BACKGROUND: Intestinal cancer often occurs in type 2 diabetic patients. The concept of increasing insulin levels and insulin-like growth factor in the blood with type 2 diabetes are stimulated with the growth and depletion of cloned cell walls, and the continuation of this process leads to the cellular deformation. This is the evidence for intestinal cancer in type 2 diabetes in population. OBJECTIVE: In this study, we aimed to find out the relationship between diabetics and intestinal cancer based on CD38 gene mutation. METHODS: Samples were collected from 200 population including normal and case ones. PCR products related to rs 6449181 of CD38 gene was amplified with ARMS-PCR technique, and a 420-bp sharp banding was observed as well. According three ARMS-PCR techniques, three primers were designed by oligo7 software. Primers include F1, F2 and R (amplifying for normal, mutant and reverse primer respectively). RESULTS: This band was observed using a primer F1 that carries the wild type nucleotide using a primer, and when it is used with the F2 primer, it brings the mutant primer to populations of patients with diabetes and diabetes-cancer. In addition, the clinical results including body mass index, blood glucose and insulin level were analyzed. The means ±SD and Tuckey's post hoc test were significant between the clinical characterization parameters between cases and healthy populations. The allelic gene frequencies and Hardy-Weinberg equilibrium between nucleotides were evaluated, and the significant level between the alleles and gene frequencies was observed. CONCLUSION: In general, the current study found that there is a relationship between diabetes and intestinal cancer among the studied populations.

Nicotinamide riboside supplementation corrects deficits in oxytocin, sociability and anxiety of CD157 mutants in a mouse model of autism spectrum disorder.

Oxytocin (OT) is a critical molecule for social recognition and memory that mediates social and emotional behaviours. In addition, OT acts as an anxiolytic factor and is released during stress. Based on the activity of CD38 as an enzyme that produces the calcium-mobilizing second messenger cyclic ADP-ribose (cADPR), CD157, a sister protein of CD38, has been considered a candidate mediator for the production and release of OT and its social engagement and anti-anxiety functions. However, the limited expression of CD157 in the adult mouse brain undermined confidence that CD157 is an authentic and/or actionable molecular participant in OT-dependent social behaviour. Here, we show that CD157 knockout mice have low levels of circulating OT in cerebrospinal fluid, which can be corrected by the oral administration of nicotinamide riboside, a recently discovered vitamin precursor of nicotinamide adenine dinucleotide (NAD). NAD is the substrate for the CD157- and CD38-dependent production of cADPR. Nicotinamide riboside corrects social deficits and fearful and anxiety-like behaviours in CD157 knockout males. These results suggest that elevating NAD levels with nicotinamide riboside may allow animals with cADPR- and OT-forming deficits to overcome these deficits and function more normally.

Associação entre diabéticos e câncer intestinal com o risco de mutação no gene CD38 na população iraniana / Association between diabetics and intestinal cancer with the risk of mutation in cd38 gene in iranian population

ABSTRACT BACKGROUND: Intestinal cancer often occurs in type 2 diabetic patients. The concept of increasing insulin levels and insulin-like growth factor in the blood with type 2 diabetes are stimulated with the growth and depletion of cloned cell walls, and the continuation of this process leads to the cellular deformation. This is the evidence for intestinal cancer in type 2 diabetes in population. OBJECTIVE: In this study, we aimed to find out the relationship between diabetics and intestinal cancer based on CD38 gene mutation. METHODS: Samples were collected from 200 population including normal and case ones. PCR products related to rs 6449181 of CD38 gene was amplified with ARMS-PCR technique, and a 420-bp sharp banding was observed as well. According three ARMS-PCR techniques, three primers were designed by oligo7 software. Primers include F1, F2 and R (amplifying for normal, mutant and reverse primer respectively). RESULTS: This band was observed using a primer F1 that carries the wild type nucleotide using a primer, and when it is used with the F2 primer, it brings the mutant primer to populations of patients with diabetes and diabetes-cancer. In addition, the clinical results including body mass index, blood glucose and insulin level were analyzed. The means ±SD and Tuckey's post hoc test were significant between the clinical characterization parameters between cases and healthy populations. The allelic gene frequencies and Hardy-Weinberg equilibrium between nucleotides were evaluated, and the significant level between the alleles and gene frequencies was observed. CONCLUSION: In general, the current study found that there is a relationship between diabetes and intestinal cancer among the studied populations.

RESUMO CONTEXTO: O câncer intestinal ocorre frequentemente em pacientes diabéticos tipo 2. O conceito que aumento dos níveis de insulina e fator de crescimento semelhante à insulina no sangue com diabetes tipo 2 sejam estimulados com o crescimento e esgotamento das paredes celulares clonadas, e a continuação desse processo levaria à deformação celular. Esta é a evidência para câncer intestinal em diabetes tipo 2 na população. OBJETIVO: Neste estudo, buscou-se descobrir a relação entre diabéticos e câncer intestinal com base na mutação genética CD38. MÉTODOS: Foram coletadas amostras de duzentos habitantes, incluindo os normais e os casos. Produtos PCR relacionados ao rs 6449181do gene CD38 foi amplificado com a técnica ARMS-PCR, e uma banda afiada de 420 bp também foi observada. De acordo com três técnicas ARMS-PCR, três primers foram projetados pelo software Oligo7. Os primers incluem F1, F2 e R (amplificando para primer normal, mutante e reverso, respectivamente). RESULTADOS: Esta banda foi observada usando um primer F1 que carrega o nucleotídeo do tipo selvagem usando um primer e quando é usado com o primer F2, ele traz o primer mutante para populações de pacientes com diabetes e diabetes-câncer. Além disso, foram analisados os resultados clínicos, incluindo índice de massa corporal, glicemia e nível de insulina. As médias ±SD e Tuckey's post hoc test foram significativas entre os parâmetros de caracterização clínica entre os casos e populações saudáveis. Foram avaliadas as frequências genéticas alélicas e o equilíbrio de Hardy-Weinberg entre nucleotídeos e observou-se o nível significativo entre os alelos e as frequências genéticas. CONCLUSÃO: Em geral, o presente estudo constatou que há relação entre diabetes e câncer intestinal entre as populações estudadas.

Effect of miR-499a-5p on damage of cardiomyocyte induced by hypoxia-reoxygenation via downregulating CD38 protein.

The aim is to investigate the mechanism of miR-499a-5p on the damage of cardiomyocyte induced by hypoxia/reoxygenation. The activity of lactate dehydrogenase (LDH), apoptosis rate and the expression of miR-499a-5p and cluster of differentiation 38 (CD38) in hypoxia-reoxygenation model cells were detected by LDH Cytotoxicity Assay Kit, flow cytometry, real-time polymerase chain reaction, and Western blot analysis, respectively. Apoptosis, the activity of LDH was detected after overexpression of miR-499a-5p or silencing of CD38 in H9c2 cells. The target relationship between miR-499a-5p and CD38 was verified by Targetscan online prediction and dual-luciferase assay. Apoptosis, the activity of LDH was detected after overexpression of miR-499a-5p and CD38. Apoptosis, the activity of LDH and the expression of CD38 were increased (P < .05) while expression of miR-499a-5p was decreased (P < .05) in hypoxia/reoxygenation model cells. Apoptosis and the activity of LDH in H9c2 cells after overexpression of miR-499a-5p or silence of CD38 were decreased (P < .05). The results of Targetscan online prediction and dual-luciferase assay indicated that CD38 was a potential target gene of miR-499a-5p. Overexpression of CD38 could reverse the inhibition of miR-499a-5p on LDH activity and apoptosis in H9c2 cells. miR-499a-5p could relief the injury of cardiomyocytes induced by hypoxia/reoxygenation via targeting CD38.

CD157 Confers Host Resistance to Mycobacterium tuberculosis via TLR2-CD157-PKCzeta-Induced Reactive Oxygen Species Production.

Recruitment of monocytes to the infection site is critical for host resistance against Mycobacterium tuberculosis CD157 has a crucial role in neutrophil and monocyte transendothelial migration and adhesion, but its role in tuberculosis (TB) is unclear. Here, we show that both mRNA and protein levels of Cd157 are significantly increased during M. tuberculosis infection. Deficiency of Cd157 impaired host response to M. tuberculosis infection by increasing bacterial burden and inflammation in the lung in the murine TB model. In vitro experiments show that the bactericidal ability was compromised in Cd157 knockout (KO) macrophages, which was due to impaired M. tuberculosis-induced reactive oxygen species (ROS) production. We further reveal that CD157 interacts with TLR2 and PKCzeta and facilitates M. tuberculosis-induced ROS production in Cd157 KO macrophages, which resulted in enhanced M. tuberculosis killing. For the clinic aspect, we observe that the expression of CD157 decreases after effective anti-TB chemotherapy. CD157 is specifically increased in pleural fluid in tuberculous pleurisy patients compared to pneumonia and lung cancer patients. Interestingly, the levels of soluble CD157 (sCD157) correlate with human peripheral monocyte-derived macrophage bactericidal activity. Exogenous application of sCD157 could compensate for macrophage bactericidal ability and restore ROS production. In conclusion, we have identified a novel protective immune function of CD157 during M. tuberculosis infection via TLR2-dependent ROS production. Application of sCD157 might be an effective strategy for host-directed therapy against TB in those with insufficient CD157 production.IMPORTANCE Tuberculosis, a chronic bacterial disease caused by Mycobacterium tuberculosis, remains a major global health problem. CD157, a dual-function receptor and ß-NAD+-metabolizing ectoenzyme, promotes cell polarization, regulates chemotaxis induced through the high-affinity fMLP receptor, and controls transendothelial migration. The role of CD157 in TB pathogenesis remains unknown. In this study, we find that both mRNA and protein levels of CD157 are significantly increased in TB. Deficiency of CD157 impaired host defense against M. tuberculosis infection both in vivo and in vitro, which is mediated by an interaction among CD157, TLR2, and PKCzeta. This interaction facilitates M. tuberculosis-induced macrophagic ROS production, which enhances macrophage bactericidal activity. Interestingly, the sCD157 level in plasma is reversibly associated with MDM M. tuberculosis killing activity. By uncovering the role of CD157 in pathogenesis of TB for the first time, our work demonstrated that application of soluble CD157 might be an effective strategy for host-directed therapy against TB.

Genome-Wide Meta-Analysis of Blood Pressure Response to ß1-Blockers: Results From ICAPS (International Consortium of Antihypertensive Pharmacogenomics Studies).

BackgroundThere exists a wide interindividual variability in blood pressure (BP) response to ß1-blockers. To identify the genetic determinants of this variability, we performed a pharmacogenomic genome-wide meta-analysis of genetic variants influencing ß1-blocker BP response.Methods and ResultsGenome-wide association analysis for systolic BP and diastolic BP response to ß1-blockers from 5 randomized clinical trials consisting of 1254 patients with hypertension of European ancestry were combined in meta-analysis and single nucleotide polymorphisms (SNPs) with P<10-4 were tested for replication in 2 independent randomized clinical trials of ß1-blocker-treated patients of European ancestry (n=1552). Regions harboring the replicated SNPs were validated in a ß1-blocker-treated black cohort from 2 randomized clinical trials (n=315). A missense SNP rs28404156 in BST1 was associated with systolic BP response to ß1-blockers in the discovery meta-analysis (P=9.33×10-5, ß=-3.21 mm Hg) and replicated at Bonferroni significance (P=1.85×10-4, ß=-4.86 mm Hg) in the replication meta-analysis with combined meta-analysis approaching genome-wide significance (P=2.18×10-7). This SNP in BST1 is in linkage disequilibrium with several SNPs with putative regulatory functions in nearby genes, including CD38, FBXL5, and FGFBP1, all of which have been implicated in BP regulation. SNPs in this genetic region were also associated with BP response in the black cohort.ConclusionsData from randomized clinical trials of 8 European ancestry and 2 black cohorts support the assumption that BST1 containing locus on chromosome 4 is associated with ß1-blocker BP response. Given the previous associations of this region with BP, this is a strong candidate region for future functional studies and potential use in precision medicine approaches for BP management and risk prediction.

Direct Gating of the TRPM2 Channel by cADPR via Specific Interactions with the ADPR Binding Pocket.

cADPR is a well-recognized signaling molecule by modulating the RyRs, but considerable debate exists regarding whether cADPR can bind to and gate the TRPM2 channel, which mediates oxidative stress signaling in diverse physiological and pathological processes. Here, we show that purified cADPR evoked TRPM2 channel currents in both whole-cell and cell-free single-channel recordings and specific binding of cADPR to the purified NUDT9-H domain of TRPM2 by surface plasmon resonance. Furthermore, by combining computational modeling with electrophysiological recordings, we show that the TRPM2 channels carrying point mutations at H1346, T1347, L1379, S1391, E1409, and L1484 possess distinct sensitivity profiles for ADPR and cADPR. These results clearly indicate cADPR is a bona fide activator at the TRPM2 channel and clearly delineate the structural basis for cADPR binding, which not only lead to a better understanding in the gating mechanism of TRPM2 channel but also shed light on a cADPR-induced RyRs-independent Ca2+ signaling mechanism.

BST1 rs4698412 allelic variant increases the risk of gait or balance deficits in patients with Parkinson's disease.

AIMS: We aimed to explore effects of bone marrow stromal cell antigen-1 (BST1) rs4698412 allelic variant on brain activation and associative clinical symptoms in Parkinson's disease (PD). METHODS: A total of 49 PD patients and 47 healthy control (HC) subjects were recruited for clinical evaluations, blood samples collection for genotypes, and resting-state functional MRI (rs-fMRI) scans. Based on BST1 rs4698412 allelic variant (G â†’ A), participants were further divided into 18 PD-GG, 31 PD-GA/AA, 20 HC-GG, and 27 HC-GA/AA carriers, which respectively indicated subjects carrying ancestral or risk allele in that locus in PD or HC. Two-way analysis of covariance (ANCOVA) was applied to investigate main effects and interactions between PD and BST1 rs4698412 allelic variant on brain function via amplitude of low-frequency fluctuations (ALFF). Spearman's correlations were then utilized to detect associations between interactive brain regions and clinical symptoms. RESULTS: Compared to HC subjects, PD patients exhibited increased ALFF values in left cerebellum_8 and cerebellum_9. Significant interaction was in right lingual gyrus, where there were the lowest ALFF values and ALFF values were only negatively associated with Timed Up and Go (TUG) test time in PD-GA/AA subgroup. CONCLUSION: BST1 rs4698412-modulated lingual gyrus functional alterations could be related to gait and balance dysfunction in PD.

CD157: From immunoregulatory protein to potential therapeutic target.

CD157/BST1 glycosylphosphatidylinositol-anchored glycoprotein is an evolutionary conserved dual-function receptor and ß-NAD+-metabolizing ectoenzyme of the ADP-ribosyl cyclases gene family. Identified as bone marrow stromal cell and myeloid cell differentiation antigen, CD157 turned out to have a wider expression than originally assumed. The functional significance of human CD157 as an enzyme remains unclear, while it was well established in mouse models. Conversely, the receptor role of CD157 has been clearly delineated. In physiological conditions, CD157 is a key player in regulating leukocyte adhesion, migration and diapedesis. Underlying these functional roles is the ability of CD157 to bind with high affinity selected extracellular matrix components within their heparin-binding domains. CD157 binding to extracellular matrix promotes its interaction with ß1 and ß2-integrins and induces the organization of a multimolecular complex that is instrumental to the delivery of synergistic outside-in signals leading to optimal cell adhesion and migration, both in physiological and in pathological situations. CD157 also regulates cell adhesion and migration and is a marker of adverse prognosis in epithelial ovarian cancer and pleural mesothelioma. This review focuses on human CD157 expression and functions and provides an overview on its role in human pathology and its emerging potential as target for antibody-mediated immunotherapy.

The Monoclonal Anti-CD157 Antibody Clone SY11B5, Used for High Sensitivity Detection of PNH Clones on WBCs, Fails to Detect a Common Polymorphic Variant Encoded by BST-1.

BACKGROUND: CD157, encoded by BST-1, has been described as a useful flow cytometric marker for the analysis of paroxysmal nocturnal hemoglobinuria (PNH) as it is a glycosylphosphatidylinositol (GPI)-linked molecule highly expressed on normal monocytes and neutrophils. We and others observed isolated CD157 signal dropouts during intended PNH analysis. We hypothesize that these negative populations occur due to an antibody failure. To investigate the reason for this finding, we compared two different anti-CD157 antibody clones for PNH analysis. METHODS: We sequenced BST-1 of CD157-negative probands that are not suffering from PNH and expressed wild type and a discovered variant form of CD157 in HEK293 cells. We compared the binding patterns of two different anti-CD157 antibody clones (SY11B5 and RF3) by flow cytometry and western blot analysis. RESULTS: When sequencing two CD157-negative probands we detected a common SNP (p.Arg145Gln) in exon 3 of BST-1. We found that only anti-CD157 antibody clone RF3 but not the more widely used clone SY11B5 was able to detect both, the wild type and the variant form of CD157 in flow cytometric experiments. CONCLUSION: The failure of anti-CD157 antibody clone SY11B5 to detect a common SNP can explain some CD157-negative cytometric data. This provides crucial knowledge for laboratories performing PNH analyses as such results can potentially lead to false-positive PNH interpretation. Our results confirm the importance of published PNH guidelines. © 2018 International Clinical Cytometry Society.