Receptor Precursor Research Articles

PLGA nanocapsules as a delivery system for a recombinant LRP-based therapeutic.

Telomerase activity is directly affected by the laminin receptor precursor (LRP) protein, a highly conserved nonintegrin transmembrane receptor, which has been shown to have therapeutic effects in ageing, and age-related diseases. Recently, it has been found that overexpression of LRP-FLAG, by plasmid transfection, leads to a significant increase in telomerase activity in cell culture models. This may indicate that upregulation of LRP can be used to treat various age-related diseases. However, transfection is not a viable treatment strategy for patients. Therefore, we present a nanoencapsulated protein-based drug synthesised using poly(lactic-co-glycolic acid) (PLGA) nanocapsules for delivery of the 37 kDa LRP protein therapeutic. PLGA nanocapsules were synthesised using the double emulsification-solvent evaporation technique. Different purification methods, including filtration and centrifugation, were tested to ensure that the nanocapsules were within the optimal size range, and the BCA assay was used to determine encapsulation efficiency. The completed drug was tested in a HEK-293 cell culture model, to investigate the effect on cell viability, LRP protein levels and telomerase activity. A significant increase in total LRP protein levels with a concomitant increase in cell viability and telomerase activity was observed. Due to the observed increase in telomerase activity, this approach could represent a safer alternative to plasmid transfection for the treatment of age-related diseases.

THU538 Use Of Multiple Functional And Structural Imaging Modalities Improves Detection Of Ectopic ACTH Tumors

Abstract Disclosure: H. Elenius: None. R. McGlotten: None. A.M. Gharib: None. L.K. Nieman: None. Introduction: In Ectopic ACTH Syndrome (EAS), Cushing's syndrome (CS) is caused by ACTH secretion from a non-pituitary tumor. Tumor resection reduces CS morbidity and mortality, but up to 38% of tumors remain occult despite repeated structural imaging. We prospectively studied whether functional PET imaging with somatostatin receptor ( 111In-pentetreotide Octreoscan [OCT], vs 68Ga DOTA0-Tyr3 octreotate DOTATATE [DOTA]) or amine precursor (18F-DOPA [F-D]) ligands would improve tumor detection. Methods: From 2014-2022, 22 EAS patients underwent imaging with F-D and DOTA PET/CT and/or MRI (1.5 and/or 3 Tesla, T) of chest/abdomen/pelvis (C/A/P), gated cardiac CT (GC-CT) and/or MRI (GC-MRI), and/or OCT before tumor resection. Pre-surgical imaging results were confirmed by pathology or biochemical cure. Results: Tumors included 16 pulmonary (pulm) neuroendocrine tumors (NET), one thymic NET, one appendiceal NET, one pheochromocytoma and one metastatic NET in mediastinal lymph nodes; two patients had tumorlets. Surgery was done if at least CT or MRI was positive; some lesions were seen only after concurrent PET scan review. Shown in decreasing order, the modalities performed as follows (number of patients = N): Sensitivity (S): CT C/A/P 100%, N 22 ; FDG-PET 100%, N 2 ; 3T MRI C/A/P 93%, N 14 ; F-D 91%, N 22 ; DOTA 86%, N 22 ; 1.5T MRI C/A/P 71%, N 21 ; GC-CT 67%, N 6 ; GC-MRI 50%, N 8 ; OCT 31%, N 13. 95% Confidence intervals (CI) overlapped for all except OCT. Positive predictive value (PPV): GC-MRI 100% ; 3T MRI C/A/P 88% ; 1.5T MRI C/A/P 84% ; DOTA 83% ; CT C/A/P 81% ; GC-CT 80% ; F-D 75% ; OCT 67% ; FDG-PET 67%. All CIs overlapped.1.5T MRI, F-D and DOTA missed a 12 mm pulm NET (false negative, FN) only seen on CT. 1.5T MRI missed three other pulm NET (6, 8 and 10 mm) seen on 3T MRI. 1.5T and 3T MRI missed a 13 mm pulm NET that abutted the heart and was seen on both gated studies - this was the only FN lesion in the 3T MRI cohort. F-D missed the 12 mm pulm NET seen on CT and the retrocardiac NET, which was DOTA +. DOTA missed three other pulm NET (6, 8 and 10 mm); all were positive on F-D. OCT detected 4/10 pulm NET, 6-25 mm, all positive on F-D and DOTA, and missed 9 tumors seen on F-D (N=8) or DOPA (N=8). F-D detected false positive (FP) lesions in seven patients while DOTA detected FP lesions in three, mostly infections or thyroid nodules. All but one patient were localized by DOTA (N=19) and/or F-D (N=20). Conclusions: As reported previously, most EAS tumors were intrathoracic. Among structural modalities, CT was the most sensitive (100%) while cardiac MRI and 3T MRI gave the highest PPV (100% and 88%). Dedicated cardiac imaging found pericardiac lesions missed on routine modalities due to motion artefacts. F-D and DOTA were significantly more sensitive (91% and 86%) than OCT (31%). DOTA detected fewer FP lesions, providing a higher PPV (83%) than F-D (75%), but with lower sensitivity. Use of multiple functional and structural scans improved tumor detection. Presentation: Thursday, June 15, 2023

Flavonoid quercetin and its glucuronide and sulfate conjugates bind to 67-kDa laminin receptor and prevent neuronal cell death induced by serum starvation

Quercetin, a dietary flavonoid, has been shown to protect against various neurodegenerative diseases with mechanisms largely unknown. After oral administration, quercetin is rapidly conjugated, and the aglycone is not detectable in the plasma and brain. However, its glucuronide and sulfate conjugates are present only at low nanomolar concentrations in the brain. Since quercetin and its conjugates have limited antioxidant capability at low nanomolar concentrations, it is crucial to determine whether they induce neuroprotection by binding to high-affinity receptors. Previously we found that (−)-epigallocatechin-3-gallate (EGCG), a polyphenol from green tea, induces neuroprotection by binding to the 67-kDa laminin receptor (67LR). Therefore, in this study, we determined whether quercetin and its conjugates bind 67LR to induce neuroprotection and compared their ability with EGCG. Based on the quenching of intrinsic tryptophan fluorescence of peptide G (residues 161–180 in 67LR), we found quercetin, quercetin-3-O-glucuronide, and quercetin-3-O-sulfate bind to this peptide with a high affinity comparable to EGCG. Molecular docking using the crystal structure of 37-kDa laminin receptor precursor supported the high-affinity binding of all these ligands to the site corresponding to peptide G. A pretreatment with quercetin (1–1000 nM) did not effectively protect Neuroscreen-1 cells from death induced by serum starvation. Contrarily, a pretreatment with low concentrations (1–10 nM) of quercetin conjugates better protected these cells than quercetin and EGCG. The 67LR-blocking antibody substantially prevented neuroprotection by all these agents, suggesting the role of 67LR in this process. Collectively, these studies reveal that quercetin induces neuroprotection primarily through its conjugates via high affinity binding to 67LR.

G1 Cell Cycle Arrest Is Induced by the Fourth Extracellular Loop of Meningococcal PorA in Epithelial and Endothelial Cells

Neisseria meningitidis is the most frequent cause of bacterial meningitis and is one of the few bacterial pathogens that can breach the blood-brain barrier (BBB). The 37/67 kDa laminin receptor (LamR) was previously identified as a receptor mediating meningococcal binding to rodent and human brain microvascular endothelial cells, which form part of the BBB. The meningococcal surface proteins PorA and PilQ were identified as ligands for this receptor. Subsequently, the fourth extracellular loop of PorA (PorA-Loop4) was identified as the LamR-binding moiety. Here, we show that PorA-Loop4 targets the 37 kDa laminin receptor precursor (37LRP) on the cell surface by demonstrating that deletion of this loop abrogates the recruitment of 37LRP under meningococcal colonies. Using a circularized peptide corresponding to PorA-Loop4, as well as defined meningococcal mutants, we demonstrate that host cell interaction with PorA-Loop4 results in perturbation of p-CDK4 and Cyclin D1. These changes in cell cycle control proteins are coincident with cellular responses including inhibition of cell migration and a G1 cell cycle arrest. Modulation of the cell cycle of host cells is likely to contribute to the pathogenesis of meningococcal disease.

Impaired SERCA2a phosphorylation causes diabetic cardiomyopathy through impinging on cardiac contractility and precursor protein processing

Abstract Diabetic cardiomyopathy (DCM) is currently a progressive and nonstoppable complication in type 2 diabetic patients. Metabolic insults and insulin resistance are involved in its pathogenesis; however, the underlying mechanisms are still not clearly understood. Here we show that calcium dysregulation can be both a cause and a consequence of cardiac insulin resistance that leads to DCM. A western diet induces the development of DCM through at least three phases in mice, among which an early phase depends on impaired Thr484-phosphorylation of sarcoplasmic/endoplasmic reticulum calcium ATPase 2a (SERCA2a) elicited by insulin resistance. Mutation of SERCA2a-Thr484 to a nonphosphorylatable alanine delays calcium re-uptake into the sarcoplasmic reticulum in the cardiomyocytes and decreases cardiac function at the baseline. Importantly, this mutation blunts the early phase of DCM, but has no effect on disease progression in the following phases. Interestingly, impairment of sarcoplasmic reticulum calcium re-uptake caused by the SERCA2a-Thr484 mutation inhibited processing of insulin receptor precursor through FURIN convertase, resulting in cardiac insulin resistance. Collectively, these data reveal a bidirectional relationship between insulin resistance and impairment of calcium homeostasis, which may underlie the early pathogenesis of DCM. Our findings have therapeutic implications for early intervention of DCM.

Neuropeptide S Encodes Stimulus Salience in the Paraventricular Thalamus

Evaluation of stimulus salience is critical for any higher organism, as it allows for prioritizing of vital information, preparation of responses, and formation of valuable memory. The paraventricular nucleus of the thalamus (PVT) has recently been identified as an integrator of stimulus salience but the neurochemical basis and afferent input regarding salience signaling have remained elusive. Here we report that neuropeptide S (NPS) signaling in the PVT is necessary for stimulus salience encoding, including aversive, neutral and reinforcing sensory input. Taking advantage of a striking deficit of both NPS receptor (NPSR1) and NPS precursor knockout mice in fear extinction or novel object memory formation, we demonstrate that intra-PVT injections of NPS can rescue the phenotype in NPS precursor knockout mice by increasing the salience of otherwise low-intensity stimuli, while intra-PVT injections of NPSR1 antagonist in wild type mice partially replicates the knockout phenotype. The PVT appears to provide stimulus salience encoding in a dose- and NPS-dependent manner. PVT NPSR1 neurons recruit the nucleus accumbens shell and structures in the prefrontal cortex and amygdala, which were previously linked to the brain salience network. Overall, these results demonstrate that stimulus salience encoding is critically associated with NPS activity in the PVT.

On the relationship between extant innate immune receptors and the evolutionary origins of jawed vertebrate adaptive immunity.

For over half a century, deciphering the origins of the genomic loci that form the jawed vertebrate adaptive immune response has been a major topic in comparative immunogenetics. Vertebrate adaptive immunity relies on an extensive and highly diverse repertoire of tandem arrays of variable (V), diversity (D), and joining (J) gene segments that recombine to produce different immunoglobulin (Ig) and T cell receptor (TCR) genes. The current consensus is that a recombination-activating gene (RAG)-like transposon invaded an exon of an ancient innate immune VJ-bearing receptor, giving rise to the extant diversity of Ig and TCR loci across jawed vertebrates. However, a model for the evolutionary relationships between extant non-recombining innate immune receptors and the V(D)J receptors of the jawed vertebrate adaptive immune system has only recently begun to come into focus. In this review, we provide an overview of non-recombining VJ genes, including CD8β, CD79b, natural cytotoxicity receptor 3 (NCR3/NKp30), putative remnants of an antigen receptor precursor (PRARPs), and the multigene family of signal-regulatory proteins (SIRPs), that play a wide range of roles in immune function. We then focus in detail on the VJ-containing novel immune-type receptors (NITRs) from ray-finned fishes, as recent work has indicated that these genes are at least 50 million years older than originally thought. We conclude by providing a conceptual model of the evolutionary origins and phylogenetic distribution of known VJ-containing innate immune receptors, highlighting opportunities for future comparative research that are empowered by this emerging evolutionary perspective.

Genome-Wide Expression Profiling of Small RNAs in Indian Strain of Rhizoctonia solani AG1-1A Reveals Differential Regulation of milRNAs during Pathogenesis and Crosstalk of Gene Regulation.

Rhizoctonia solani AG1-1A is a necrotrophic fungus that causes sheath blight disease in rice. The reliable resistant source against this phytopathogenic fungus is not available in the gene pool of rice. Better understanding of pathogen genomics and gene regulatory networks are critical to devise alternate strategies for developing resistance against this noxious pathogen. In this study, miRNA-like RNAs (milRNAs) of an Indian strain of R. solani were identified by deep sequencing of small RNAs. We identified 128 known and 22 novel milRNAs from 20,963,123 sequence reads. These milRNAs showed 1725 target genes in the fungal genome which include genes associated with growth, development, pathogenesis and virulence of R. solani. Notably, these fungal milRNAs showed their target genes in host (rice) genome also which were later verified by qRT-PCR. The host target genes are associated with auxin metabolism, hypersensitive response, defense genes, and genes related to growth and development of rice. Osa-vacuolar-sorting receptor precursor: Rhi-milR-13, Osa-KANADI1:Rhi-milR-124, Osa-isoflavone reductase: Rhi-milR-135, Osa-nuclear transcription factor Y:Rhi-milR-131, Osa-NB-ARC domain containing protein: Rhi-milR-18, and Osa-OsFBX438: Rhi-milR-142 are notable potential regulons of host target genes: fungal milRNAs that need to be investigated for better understanding of the crosstalk of RNAi pathways between R. solani and rice. The detailed expression analysis of 17 milRNAs by qRT-PCR was analysed during infection at different time points of inoculation, at different growth stages of the host, in four different genotypes of the host, and also in four different strains of fungi which revealed differential regulation of milRNAs associated with pathogenesis and virulence. This study highlights several important findings on fungal milRNAs which need to be further studied and characterized to decipher the gene expression and regulation of this economically important phytopathogen.

Adenosine Deaminases Acting on RNA (ADARs) and Viral Infections.

C6 deamination of adenosine (A) to inosine (I) in double-stranded RNA (dsRNA) is catalyzed by a family of enzymes known as ADARs (adenosine deaminases acting on RNA) encoded by three genes in mammals. Alternative promoters and splicing produce two ADAR1 proteins, an interferon-inducible cytoplasmic p150 and a constitutively expressed p110 that like ADAR2 is a nuclear enzyme. ADAR3 lacks deaminase activity. A-to-I editing occurs with both viral and cellular RNAs. Deamination activity is dependent on dsRNA substrate structure and regulatory RNA-binding proteins and ranges from highly site selective with hepatitis D RNA and glutamate receptor precursor messenger RNA (pre-mRNA) to hyperediting of measles virus and polyomavirus transcripts and cellular inverted Alu elements. Because I base-pairs as guanosine instead of A, editing can alter mRNA decoding, pre-mRNA splicing, and microRNA silencing. Editing also alters dsRNA structure, thereby suppressing innate immune responses including interferon production and action.

A genome-wide association study to identify candidate genes for erectile dysfunction.

Erectile dysfunction (ED) can be caused by different diseases and controlled by several genetic networks. In this study, to identify the genes related to ED, the expression profiles of normal and ED samples were investigated by the Gene Expression Omnibus (GEO) database. Seventeen genes were identified as associated genes with ED. The protein and nucleic acid sequences of selected genes were retrieved from the UCSC database. Selected genes were diverse according to their physicochemical properties and functions. Category function revealed that selected genes are involved in pathways related to humans some diseases. Furthermore, based on protein interactions, genes associated with the insulin pathway had the greatest interaction with the studied genes. To identify the common cis-regulatory elements, the promoter site of the selected genes was retrieved from the UCSC database. The Gapped Local Alignment of Motifs tool was used for finding common conserved motifs into the promoter site of selected genes. Besides, INSR protein as an insulin receptor precursor showed a high potential site for posttranslation modifications, including phosphorylation and N-glycosylation. Also, in this study, two Guanine-Cytosine (GC)-rich regions were identified as conserved motifs in the upstream of studied genes which can be involved in regulating the expression of genes associated with ED. Also, the conserved binding site of miR-29-3p that is involved in various cancers was observed in the 3' untranslated region of genes associated with ED. Our study introduced new genes associated with ED, which can be good candidates for further analyzing related to human ED.

Genetic and functional analysis of a Pacific hagfish opioid system.

The actions of endogenous opioids and nociceptin/orphanin FQ are mediated by four homologous G protein-coupled receptors that constitute the opioid receptor family. However, little is known about opioid systems in cyclostomes (living jawless fish) and how opioid systems might have evolved from invertebrates. Here, we leveraged de novo transcriptome and low-coverage whole-genome assembly in the Pacific hagfish (Eptatretus stoutii) to identify and characterize the first full-length coding sequence for a functional opioid receptor in a cyclostome. Additionally, we define two novel endogenous opioid precursors in this species that predict several novel opioid peptides. Bioinformatic analysis shows no closely related opioid receptor genes in invertebrates with regard either to the genomic organization or to conserved opioid receptor-specific sequences that are common in all vertebrates. Furthermore, no proteins analogous to vertebrate opioid precursors could be identified by genomic searches despite previous claims of protein or RNA-derived sequences in several invertebrate species. The presence of an expressed orthologous receptor and opioid precursors in the Pacific hagfish confirms that a functional opioid system was likely present in the common ancestor of all extant vertebrates some 550 million years ago, earlier than all previous authenticated accounts. We discuss the premise that the cyclostome and vertebrate opioid systems evolved from invertebrate systems concerned with antimicrobial defense and speculate that the high concentrations of opioid precursors in tissues such as the testes, gut, and activated immune cells are key remnants of this evolutionary role.

The Paracaspase MALT1 Acts Independently of Pre-B-Cell Receptor Signaling As a Key Factor in Leukemic Cell Survival in Precursor B-Cell Acute Lymphoblastic Leukemia

Despite a central role for B-cell receptor precursor (pre-BCR) pathway in precursor B-cell acute lymphoblastic leukemia (B-ALL), there is limited available data on therapies that aim to disrupt this pathway. Mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) is a para-caspase required for BCR-mediated NF-κB activation. We recently showed that targeting MALT1 with the small molecule inhibitor MI2 is effective in CLL, including drug-resistant clones (Saba Can Res 2017). We sought to examine the role of MALT1 in B-ALL and determine the biological consequences of inhibiting its activity. First, we tested MALT1 expression by immunoblot in B-ALL using 17 cell lines representing the disease spectrum (7 pro-B: REH, SEMK2, TOM1, RS4;11, NALM21, Z119, BV173; 8 pre-B: HB11;19, NALM6, RCH-ACV, SMS-SB, 697, KASUMI2, KOPN8, HPB-NULL; and 2 mature/Burkitt: 2F7, RAJI), and found that MALT1 was expressed in all cell lines at different levels. To determine sensitivity to MALT1 inhibition we used two molecules: Z-VRPR-fmk, a highly selective MALT1 blocking peptide, and MI2, a small molecule MALT1 inhibitor. Z-VRPR-fmk resulted in a dramatic cell growth inhibition in most of our B-ALL cell lines, with appropriate positive (TMD8) and negative (K562) controls, independent of the cell-of-origin (pro, pre, mature) or the presence of the Philadelphia chromosome. We did not observe a clear correlation between MALT1 level and degree of sensitivity to Z-VRPR-fmk. Interestingly, the two ibrutinib-resistant cell lines RS4;11 and 697, were amongst the top sensitive cell lines to MALT1 inhibition. A similar pattern of cell sensitivity was observed when these cell lines were treated with MI2, resulting in an IC50 at 48h of 0.2 µM in RS4;11 and < 0.5 µM in other sensitive cell lines, which is consistent with published data in sensitive DLBCL cell lines (IC50, 0.2-0.5 µM), and our data on the CLL cell line MEC1 (IC50, 0.2 µM). We then tested freshly collected PBMCs from patients with various blood cancers presenting with a leukemic phase against serial dilutions of MI2 for 48h (7 B-ALL, 24 CLL, and 4 CML). In addition, we included normal B-cells collected from five volunteers. Interestingly, B-ALL samples showed the highest sensitivity to MI2, followed by CLL, while the rest were resistant. The proteolytic activity of MALT1 can be studied by measuring its ability to cleave its targets such as A20, CYLD, BCL10, Roquin, Regnase and RelB. Surprisingly, with the exception of the Burkitt cell line 2F7, we did not detect cleavage of these targets at baseline, nor after proteasomal inhibition with MG-132 or following crosslinking of pre-BCR with anti-IgM in pre-B ALL, the latter successfully increased AKT phosphorylation. The constitutive activation of MALT1 in 2F7 was effectively inhibited by Z-VRPR-fmk as determined by a marked reduction in targets cleavage concomitant with an increase in full length proteins. We are expanding the mature B-ALL cell line cohort to include TANOUE, BALL-1, DAUDI, GA-10, and NC-37 cell lines to further explore to role of MALT1 in this disease subset. Collectively, these data highly suggest distinct roles for MALT1 in B-ALL: pro and pre-B-ALL vs. mature B-ALL. To explore the possibility of distinct role for MALT1 in B-ALL, arguably independent of BTK and of signaling through BCR, we used RNA sequencing to determine the changes in gene expression profiling following a 24h treatment with Z-VRPR-fmk in 3 highly sensitive B-ALL cell lines (RS4;11, HPB-NULL, and 697). Out of 39,514 tested genes, there were 160 genes whose expression changed ≥ 2-fold at P < 0.05 (84 down- and 76 up-regulated). Gene Set Enrichment Analysis (GSEA) identified 34 Hallmark and Oncogenic Signatures gene sets relevant to B-ALL that were all downregulated by Z-VRPR-fmk (FDR < 10%, and normalized enrichment score (NES) ≥ 1.50). Among those gene sets, mTOR-S6K and TANK-binding kinase 1 (TBK1)-dependent gene signatures stood out as the most affected. MALT1 was shown to be involved in the ribosomal protein S6 phosphorylation through activation of mTOR/AKT signaling. Indeed, treatment with MI2 and Z-VRPR resulted in a significant decrease in S6 phosphorylation in RS4;11 and SEMK2. In conclusion, MALT1 plays a critical role in B-ALL survival likely through a novel mechanism that involves mTOR-S6K pathway, independently from pre-BCR/BCR signaling. Supported by a grant from the Ladies Leukemia League, Inc., of the Gulf South Region. Disclosures Saba: Kyowa Kirin: Consultancy; AbbVie: Consultancy; Janssen: Consultancy, Speakers Bureau; Pharmacyclics: Consultancy, Speakers Bureau. Melnick:Epizyme: Consultancy; Janssen: Research Funding; Constellation: Consultancy. Wiestner:Merck: Research Funding; Nurix: Research Funding; Pharmayclics: Research Funding; Acerta: Research Funding. Burger:AstraZeneca: Honoraria; Aptose Biosciences, Inc: Research Funding; Gilead Sciences: Research Funding; Janssen Pharmaceuticals: Consultancy, Honoraria; Pharmacyclics, an AbbVie company: Research Funding; BeiGene: Research Funding. Safah:Celgene: Speakers Bureau; Incyte: Speakers Bureau; Verastem: Honoraria, Speakers Bureau; Jazz: Speakers Bureau; Amgen: Honoraria, Speakers Bureau.

Differential Aggregation and Phosphorylation of Alpha Synuclein in Membrane Compartments Associated With Parkinson Disease.

The aggregation of α-synuclein (α-syn) is a major factor behind the onset of Parkinson’s disease (PD). Sublocalization of this protein may be relevant for the formation of multimeric α-syn oligomeric configurations, insoluble aggregates that form Lewy bodies in PD brains. Processing of this protein aggregation is regulated by associations with distinct lipid classes. For instance, instability of lipid raft (LR) microdomains, membrane regions with a particular lipid composition, is an early event in the development of PD. However, the relevance of membrane microdomains in the regulation and trafficking of the distinct α-syn configurations associated with PD remains unexplored. In this study, using 6- and 14-month-old healthy and MPTP-treated animals as a model of PD, we have investigated the putative molecular alterations of raft membrane microstructures, and their impact on α-syn dynamics and conformation. A comparison of lipid analyses of LR microstructures and non-raft (NR) fractions showed alterations in gangliosides, cholesterol, polyunsaturated fatty acids (PUFA) and phospholipids in the midbrain and cortex of aged and MPTP-treated mice. In particular, the increase of PUFA and phosphatidylserine (PS) during aging correlated with α-syn multimeric formation in NR. In these aggregates, α-syn was phosphorylated in pSer129, the most abundant post-transductional modification of α-syn promoting toxic aggregation. Interestingly, similar variations in PUFA and PS content correlating with α-syn insoluble accumulation were also detected in membrane microstructures from the human cortex of incidental Parkinson Disease (iPD) and PD, as compared to healthy controls. Furthermore, structural changes in membrane lipid microenvironments may induce rearrangements in raft-interacting proteins involved in other neuropathologies. Therefore, we also investigated the dynamic of other protein markers involved in cognition and memory impairment such as metabotropic glutamate receptor 5 (mGluR5), ionotropic NMDA receptor (NMDAR2B), prion protein (PrPc) and amyloid precursor protein (APP), whose activity depends on membrane lipid organization. We observed a decline of these protein markers in LR fractions with the progression of aging and pathology. Overall, our findings demonstrate that lipid alterations in membranous compartments promoted by brain aging and PD-like injury may have an effect on α-syn aggregation and segregation in abnormal multimeric structures.

Identification of Two Nonrearranging IgSF Genes in Chicken Reveals a Novel Family of Putative Remnants of an Antigen Receptor Precursor.

In this study, we identified a pair of nonrearranging VJ-joined Ig superfamily genes, termed putative remnants of an Ag receptor precursor (PRARP) genes, in chicken. Both genes encode a single V-set Ig domain consisting of a canonical J-like segment and a potential immunoreceptor tyrosine-based inhibitory or switch motif in the cytoplasmic region. In vitro experiments showed that both genes were expressed at the cell surface as membrane proteins, and their recombinant products formed a monomer and a disulfide-linked homodimer or a heterodimer. These two genes were mainly expressed in B and T cells and were upregulated in response to stimulation with poly(I:C) in vitro and vaccination in vivo. Orthologs of PRARP have been identified in bony fish, amphibians, reptiles, and other birds, and a V-C1 structure similar to that of Ig or TCR chains was found in all these genes, with the exception of those in avian species, which appear to contain degenerated C1 domains or divergent Ig domains. Phylogenetic analyses suggested that the newly discovered genes do not belong to any known immune receptor family and appear to be a novel gene family. Further elucidation of the functions of PRARP and their origin might provide significant insights into the evolution of the immune system of jawed vertebrates.

The expression pattern of calcium signaling-related genes during smoltification of Salmo salar in productive conditions.

Variations in the mRNA expression of hepatic and muscle genes that are related to calcium signaling were analyzed by real-time qPCR in farmed Atlantic salmon (Salmo salar L. 1758) to determine changes in expression between parr and smolt stages. These organs were selected due to their close relationship with calcium signaling and metabolism (e.g., glycolysis, oxidative phosphorylation, muscle contraction). Differential expression between smolt and parr specimens and between organs was observed. Compared to parr specimens, smolts exhibited upregulated expression of the calcitonin receptor precursor, calcitonin receptor, calcitonin isoform, parathyroid hormone, and calmodulin in the liver. This pattern was inverse in muscle, with the exception of calmodulin, which was significantly upregulated in smolts compared to parr. Additionally, plasma calcium was decreased in the smolt condition. This study is the first to characterize the expression pattern of calcium signaling-related genes in the liver and muscle of parr and smolt S. salar. However, further functional studies are required to obtain a wider understanding about the physiological changes that accompany the productive conditions during smoltification.

Source contributions of surface ozone in China using an adjoint sensitivity analysis

Air pollution has become an adverse environmental problem in China, resulting in serious public health impacts. This study advanced and applied the CMAQ adjoint model to quantitatively assess the source-receptor relationships between surface ozone (O3) changes over different receptor regions and precursor emissions across all locations in China. Five receptor regions were defined based on the administrative division, including northern China (NC), southern China (SC), Pearl River Delta region (PRD), Yangtz River Delta region (YRD), and Beijing-Tianjin-Hebei region (BTH). Our results identified the different influential pathways of atmospheric processes and emissions to O3 pollution. We found that the atmospheric processes such as horizontal and vertical advection could offset the O3 removal through chemical reactions in VOC-limited areas inside the receptor regions. In addition, O3 pollution can be induced by transport of O3 directly or its precursors. Our results of relative source contributions to O3 show that transboundary O3 pollution was significant in SC, NC and YRD, while the O3 pollution in PRD and BTH were more contributed by local sources. Anhui, Hubei and Jiangsu provinces were the three largest source areas of NOx and VOC emissions to O3 in SC (>52%) and YRD (>69%). NOx and VOC emissions from Tianjin and Beijing were the largest contributors to O3 in NC (>34%) and BTH (>51%). PRD was the dominant source areas of NOx (>89%) and VOC emissions (~98%) to its own regional O3.

Bone marrow infiltrated Lnc-INSR induced suppressive immune microenvironment in pediatric acute lymphoblastic leukemia

Immune escape due to immunosuppressive microenvironments, such as those associated with regulatory T (Treg) cells is highly associated with initial occurrence and development of solid tumors or hematologic malignancies. Here, we employed high-throughput transcriptome screening to demonstrate immunosuppression-associated increases in the long noncoding (lnc) RNA lnc-insulin receptor precursor (INSR), which was corrected with INSR expression in CD4+ T cells extracted from the bone marrow of patients with childhood acute T lymphoblastic leukemia. Loss-of-function and gain-of-function assays in vitro and in vivo revealed that membrane-localized and cytoplasm-localized lnc-INSR promoted Treg distribution and decreased the percentage of cytotoxic T lymphocytes, which induced tumor growth. Through direct binding with INSR, lnc-INSR blocked the INSR ubiquitination site, causing abnormal activation of INSR and the phosphatidylinositide 3-kinase/AKT-signaling pathway. These results indicated that lnc-INSR might promote immune suppression by enhancing Treg-cell differentiation and serve as valuable therapeutic targets in the immunosuppressive tumor microenvironment.

Effects of water extract from epimedium on neuropeptide signaling in an ovariectomized osteoporosis rat model

Ethnopharmacological relevanceFor the past millennium, water extract from Epimedium (dried leaves of Epimedium brevicornu Maxim.) has been widely used for bone disease therapy in traditional Chinese medicine and has been reported to exhibit salutary effects on osteoporosis in clinical trials. The therapeutic effect of Epimedium is associated with the function of the brain in traditional Chinese medicine theory. Study aimTo determine the potential relationship between treating osteoporosis with Epimedium and neuropeptide regulation. Materials and methodsWater extract from Epimedium was qualitatively and quantitatively analyzed with HPLC-TOF-MS. Ovariectomized rats were used as an osteoporosis model and were treated orally with water extract from Epimedium 16 weeks after surgery to mimic clinical therapy. After treatment, gene expression and protein levels of four neuropeptides, as well as their main receptors or receptor precursors including; neuropeptide Y (NPY) and its receptors NPY 1 (NPYR1) and 2; calcitonin gene-related peptide and its receptor precursor calcitonin receptor-like receptor (CRLR); vasoactive intestinal peptide (VIP) and its receptor VIP 1 (VIP1R) and 2; and substance P (SP) and its receptor neurokinin 1 receptor (NK1R) were detected in samples taken from bone, brain and spinal cord. ResultsTreatment with water extract from Epimedium prevented bone mineral loss and reduced femoral bone strength decline associated with osteoporosis. Detection of neuropeptides showed that treatment also affected neuropeptide in the brain/spinal cord/bone axis; specifically, treatment increased brain NPY, bone NPY1R, bone CRLR, bone and spinal cord VIP and VIP2R, bone SP, and brain and spinal cord NK1R. ConclusionThe effects of osteoporosis can largely be reduced by treatment with Epimedium most likely through a mechanism associated with several neuropeptides involved in regulation of the brain/spinal cord/bone axis. These novel results contribute to existing literature regarding the possible mechanisms of habitual use of Epimedium in the treatment of osteoporosis.

Immune regulation by microbiome metabolites.

Commensal microbes and the host immune system have been co-evolved for mutual regulation. Microbes regulate the host immune system, in part, by producing metabolites. A mounting body of evidence indicates that diverse microbial metabolites profoundly regulate the immune system via host receptors and other target molecules. Immune cells express metabolite-specific receptors such as P2X7 , GPR41, GPR43, GPR109A, aryl hydrocarbon receptor precursor (AhR), pregnane X receptor (PXR), farnesoid X receptor (FXR), TGR5 and other molecular targets. Microbial metabolites and their receptors form an extensive array of signals to respond to changes in nutrition, health and immunological status. As a consequence, microbial metabolite signals contribute to nutrient harvest from diet, and regulate host metabolism and the immune system. Importantly, microbial metabolites bidirectionally function to promote both tolerance and immunity to effectively fight infection without developing inflammatory diseases. In pathogenic conditions, adverse effects of microbial metabolites have been observed as well. Key immune-regulatory functions of the metabolites, generated from carbohydrates, proteins and bile acids, are reviewed in this article.

Anti–HIV-1 B cell responses are dependent on B cell precursor frequency and antigen-binding affinity

The discovery that humans can produce potent broadly neutralizing antibodies (bNAbs) to several different epitopes on the HIV-1 spike has reinvigorated efforts to develop an antibody-based HIV-1 vaccine. Antibody cloning from single cells revealed that nearly all bNAbs show unusual features that could help explain why it has not been possible to elicit them by traditional vaccination and instead would require a sequence of different immunogens. This idea is supported by experiments with genetically modified immunoglobulin (Ig) knock-in mice. Sequential immunization with a series of specifically designed immunogens was required to shepherd the development of bNAbs. However, knock-in mice contain superphysiologic numbers of bNAb precursor-expressing B cells, and therefore how these results can be translated to a more physiologic setting remains to be determined. Here we make use of adoptive transfer experiments using knock-in B cells that carry a synthetic intermediate in the pathway to anti-HIV-1 bNAb development to examine how the relationship between B cell receptor affinity and precursor frequency affects germinal center (GC) B cell recruitment and clonal expansion. Immunization with soluble HIV-1 antigens can recruit bNAb precursor B cells to the GC when there are as few as 10 such cells per mouse. However, at low precursor frequencies, the extent of clonal expansion is directly proportional to the affinity of the antigen for the B cell receptor, and recruitment to GCs is variable and dependent on recirculation.