Functional Annotation Clustering Research Articles

Effective knockdown-replace gene therapy in a novel mouse model of DNM1 developmental and epileptic encephalopathy

Effective gene therapy for gain-of-function or dominant-negative disease mutations may require eliminating expression of the mutant copy together with wildtype replacement. We evaluated such a “knockdown-replace” strategy in a mouse model of DNM1 disease, a debilitating and intractable neurodevelopmental epilepsy. To challenge the approach robustly, we expressed a patient-based variant in GABAergic neurons - which resulted in growth delay and lethal seizures evident by postnatal week three - and delivered to newborn pups an AAV9-based vector encoding a ubiquitously-expressed, Dnm1-specific interfering RNA (RNAi) bivalently in tail-to-tail configuration with a neuron-specific, RNAi-resistant, codon-optimized Dnm1 cDNA. Pups receiving RNAi or cDNA alone fared no better than untreated, whereas the vast majority of mutants receiving modest doses survived with almost full growth recovery. Synaptic recordings of cortical neurons derived from treated pups revealed that significant alterations in transmission from inhibitory to excitatory neurons were rectified by bivalent vector application. To examine the mutant transcriptome and impact of treatment, we used RNAseq and functional annotation clustering. Mutants displayed abnormal expression of >1000 genes in highly significant and relevant functional clusters, clusters that were abrogated by treatment. Together these results suggest knockdown-replace as a potentially effective strategy for treating DNM1 and related genetic neurodevelopmental disease.

CRABP1-complexes in exosome secretion

BackgroundCellular retinoic acid binding protein 1 (CRABP1) mediates rapid, non-canonical activity of retinoic acid (RA) by forming signalosomes via protein-protein interactions. Two signalosomes have been identified previously: CRABP1-MAPK and CRABP1-CaMKII. Crabp1 knockout (CKO) mice exhibited altered exosome profiles, but the mechanism of CRABP1 action was unclear. This study aimed to screen for and identify novel CRABP1 signalosomes that could modulate exosome secretion by using a combinatorial approach involving biochemical, bioinformatic and molecular studies.MethodsImmunoprecipitation coupled with mass spectrometry (IP-MS) identified candidate CRABP1-interacting proteins which were subsequently analyzed using GO Term Enrichment, Functional Annotation Clustering; and Pathway Analysis. Gene expression analysis of CKO samples revealed altered expression of genes related to exosome biogenesis and secretion. The effect of CRABP1 on exosome secretion was then experimentally validated using CKO mice and a Crabp1 knockdown P19 cell line.ResultsIP-MS identified CRABP1-interacting targets. Bioinformatic analyses revealed significant association with actin cytoskeletal dynamics, kinases, and exosome secretion. The effect of CRABP1 on exosome secretion was experimentally validated by comparing circulating exosome numbers of CKO and wild type (WT) mice, and secreted exosomes from WT and siCRABP1-P19 cells. Pathway analysis identified kinase signaling and Arp2/3 complex as the major pathways where CRABP1-signalosomes modulate exosome secretion, which was validated in the P19 system.ConclusionThe combinatorial approach allowed efficient screening for and identification of novel CRABP1-signalosomes. The results uncovered a novel function of CRABP1 in modulating exosome secretion, and suggested that CRABP1 could play roles in modulating intercellular communication and signal propagation.

Effects of High-Dose Cyclophosphamide on Ultrastructural Changes and Gene Expression Profiles in the Cardiomyocytes of C57BL/6J Mice.

The pathogenesis of cyclophosphamide (CY)-induced cardiotoxicity remains unknown, and methods for its prevention have not been established. To elucidate the acute structural changes that take place in myocardial cells and the pathways leading to myocardial damage under high-dose CY treatments, we performed detailed pathological analyses of myocardial tissue obtained from C57BL/6J mice subjected to a high-dose CY treatment. Additionally, we analysed the genome-wide cardiomyocyte expression profiles of mice subjected to the high-dose CY treatment. Treatment with CY (400 mg/kg/day intraperitoneally for two days) caused marked ultrastructural aberrations, as observed using electron microscopy, although these aberrations could not be observed using optical microscopy. The expansion of the transverse tubule and sarcoplasmic reticulum, turbulence in myocardial fibre travel, and a low contractile protein density were observed in cardiomyocytes. The high-dose CY treatment altered the cardiomyocyte expression of 1210 genes (with 675 genes upregulated and 535 genes downregulated) associated with cell-cell junctions, inflammatory responses, cardiomyopathy, and cardiac muscle function, as determined using microarray analysis (|Z-score| > 2.0). The expression of functionally important genes related to myocardial contraction and the regulation of calcium ion levels was validated using real-time polymerase chain reaction analysis. The results of the gene expression profiling, functional annotation clustering, and Kyoto Encyclopedia of Genes and Genomes pathway functional-classification analysis suggest that CY-induced cardiotoxicity is associated with the disruption of the Ca2+ signalling pathway.

P155 Gene expression in hypermobility and the role of inflammation

Abstract Background/Aims Hypermobile conditions, including Ehlers-Danlos syndrome and joint hypermobility syndrome, encompass a broad spectrum of heterogenous clinical entities characterised by excessive range of joint movements and variable extra-articular features. The etiological basis of these conditions is thought to relate to abnormal collagen assembly, which impairs the structural integrity of connective tissue, although precise mechanisms remain both debated and incompletely understood. Despite the established strong heritability of hypermobility, a definitive genetic cause remains unidentifiable in most hypermobile patients, highlighting the need to further characterize the genetic landscape of hypermobile conditions. In this study, we therefore employ transcriptomic analysis as an alternate means of elucidating the genetic basis of hypermobility. Methods We tested for the effects of hypermobility on gene expression, at baseline and following an inflammatory challenge, by re-analysing existing transcriptomic data gathered from healthy subjects and patients with fibromyalgia and chronic fatigue using total RNA sequencing of blood samples (Illumina NextSeq 500). From each participant, two blood samples were taken on separate occasions: one after a saline injection and the other after an inflammatory challenge, the typhoid vaccination, in a cross-over design. Participants were assigned to hypermobile or non-hypermobile conditions in accordance with criterion 1: generalized joint hypermobility of the Diagnostic Criteria for Hypermobile Ehlers-Danlos Syndrome (hEDS) produced by the International Consortium on Ehlers-Danlos Syndromes & Related disorders. Differential gene expression analysis comparing hypermobile and non-hypermobile participants was performed using EdgeR software in R studio. Baseline differences were determined by comparing post-saline samples between groups. Differential responses to the inflammatory challenge were detected by comparison of post-typhoid samples between groups. Gene ontology on differentially expressed genes was performed using DAVID’s Functional Annotation Clustering tool. Results We found 288 differentially expressed genes post-saline (i.e at baseline) and 1113 post-typhoid at p < 0.05 although none passed false discovery rate. At baseline, differentially expressed genes were significantly enriched for nuclear, endoplasmic reticulum, and microtubular genes (enrichment score = 2.96, 2.02, 1.3 respectively); and post-typhoid, for 24 clusters, the three most significant being synaptic, ion transport, and plasma membrane genes (enrichment score = 11.34, 8.71, and 7.3 respectively). Conclusion These data demonstrate distinct patterns of gene expression, both at baseline and during inflammation, which implicate potential biological pathways in the pathophysiology of hypermobility. These results also contribute to a growing understanding of the genetic basis of hypermobility and may inform future higher-powered studies to validate our findings. Disclosure J. Porter: None. M. Amato: None. K. Themelis: None. H. Critchley: None. S. Newbury: None. K. Davies: None. N. Harrison: None. B. Towler: None. J. Eccles: Grants/research support; J.E. has received funding from Versus Arthritis, National Institute for Health Research and the Fibroduck Foundation.

307 Revealing Candidate Inherited Retinal Disease Candidates via Genome-wide Screening of Knockout Mice

OBJECTIVES/GOALS: The goal of this study is to reveal strong candidate genes for inherited retinal diseases (IRDs) in humans to better understand the mechanisms behind IRD development and reveal potential therapeutic targets. We hope these findings will help improve our understanding of IRDs and, subsequently, diagnostic accuracy and prognosis for IRD patients. METHODS/STUDY POPULATION: The goal of the International Mouse Phenotyping Consortium is to identify the function of all protein-coding genes in the mouse genome via generation and phenotypic characterization of single gene knockout (KO) mice. Using this database, we identified all KO strains associated with abnormal retinal phenotypes, removed all RNA coding genes and pseudogenes, converted to human orthologues, and conducted a literature search for existing research regarding candidate IRD genes and retinal function/abnormalities. A similar process was used for RetNet genes. Subsequently, we performed bioinformatics analysis, including functional annotation (e.g. panther-db), pathway analysis (e.g. KEGG), and string-db to visualize known and predicted protein-protein interactions between the two data sets. RESULTS/ANTICIPATED RESULTS: Analysis of the IMPC database revealed, out of 8481 phenotyped genes, 572 unique protein coding genes were associated with 14 categories of retinal abnormalities such as abnormal retinal vasculature and abnormal retinal thickness, 377 of which have never been associated with retinal pathology in humans or mice. Pathway analysis of the IMPC database highlighted a general metabolism pathway as well as PI3K-Akt and MAPK pathways, not found in RetNet pathway results. Unique clusters from functional annotation clustering of the IMPC include DNA methylation and protein ubiquination. Visualization of protein-protein interactions in string-db between the IMPC (mouse) and RetNet (human) revealed 4 clusters of interest with gold standard RetNet IRD proteins interacting with candidate IMPC IRD proteins. DISCUSSION/SIGNIFICANCE: IMPC analysis revealed 572 candidate IRD genes, 377 of which are novel with no existing independent research related to the retina outside of the IMPC. Bioinformatic analysis reveals 4 strong clusters of interest through string-db where a gold standard RetNet gene interacts with candidate IRD genes as well as many functional pathways of interest.

Inhibition of anti-tumour reactivity of immune cells in the salivary gland cancer: A proteomic approach

BackgroundAdenoid cystic carcinoma (ACC), mucoepidermoid carcinoma (MEC), and oral squamous cell carcinoma (OSCC) respond differently to immunotherapy. Pembrolizumab, an immune checkpoint inhibitor, has been approved by the Food and Drug Administration for the treatment of squamous cell carcinomas of the head and neck region. While MEC has shown some response to pembrolizumab; however, ACC is the least responsive. At the molecular level, head and neck cancers produce immunosuppressive molecules, resulting in immune evasion. Therefore, we hypothesised that salivary gland cancer cells produce a higher number of immunosuppressive proteins that cause suppression of the immune system's anti-tumour reactivity. MethodTo determine differential protein expressions in OSCC, MEC, and ACC, we constructed cancer–immune cell co-culture models using different oral and salivary gland cancer cells. We performed SWATH, proteome profilers, gene ontology biological function, functional annotation clustering and protein interaction network analysis of all cancer samples in the co-culture models. ResultsAnalysis of the acquired data showed that the overexpressed proteins in the OSCC cells and participated more in metabolic process, while in the salivary gland cancer cells, overexpressed proteins participated more in immune processes, immune checkpoint pathway. Upon protein function analysis of salivary gland cells, the overexpressed proteins found negatively affecting immune process and checkpoint pathway proteins. ConclusionOverall, we conclude that salivary gland cancer is less responsive to immunotherapy, possibly because of the high presence of immunosuppressive proteins. However, further analysis is needed to verify the biological functions and interactive partners of each differentially expressed protein in ACC cells.

Identification of genetic variants associated with anterior cruciate ligament rupture and AKC standard coat color in the Labrador Retriever

Canine anterior cruciate ligament (ACL) rupture is a common complex disease. Prevalence of ACL rupture is breed dependent. In an epidemiological study, yellow coat color was associated with increased risk of ACL rupture in the Labrador Retriever. ACL rupture risk variants may be linked to coat color through genetic selection or through linkage with coat color genes. To investigate these associations, Labrador Retrievers were phenotyped as ACL rupture case or controls and for coat color and were single nucleotide polymorphism (SNP) genotyped. After filtering, ~ 697 K SNPs were analyzed using GEMMA and mvBIMBAM for multivariate association. Functional annotation clustering analysis with DAVID was performed on candidate genes. A large 8 Mb region on chromosome 5 that included ACSF3, as well as 32 additional SNPs, met genome-wide significance at P < 6.07E-7 or Log10(BF) = 3.0 for GEMMA and mvBIMBAM, respectively. On chromosome 23, SNPs were located within or near PCCB and MSL2. On chromosome 30, a SNP was located within IGDCC3. SNPs associated with coat color were also located within ADAM9, FAM109B, SULT1C4, RTDR1, BCR, and RGS7. DZIP1L was associated with ACL rupture. Several significant SNPs on chromosomes 2, 3, 7, 24, and 26 were located within uncharacterized regions or long non-coding RNA sequences. This study validates associations with the previous ACL rupture candidate genes ACSF3 and DZIP1L and identifies novel candidate genes. These variants could act as targets for treatment or as factors in disease prediction modeling. The study highlighted the importance of regulatory SNPs in the disease, as several significant SNPs were located within non-coding regions.

Relative Abundance of Spermadhesin-1 in the Seminal Plasma of Young Nellore Bulls Is in Agreement with Reproductive Parameters.

This study aimed to evaluate the proteomic profile of seminal plasma from young Nellore bulls. We used 20 bulls aged between 19.8 and 22.7 months, divided into two groups according to the results of the Breeding Soundness Evaluation (BSE): approved (FIT n = 10) and not approved (UNFIT n = 10). The scrotal perimeter was measured and a semen collection was performed through electroejaculation. The percentage of sperm motility, mass motility, and sperm vigor were calculated using conventional microscopy, and the percentage of sperm abnormalities was calculated using phase-contrast microscopy of all ejaculates. Seminal plasma was separated from spermatozoa using centrifugation and processed for proteomic analysis by LC-MS/MS. Seminal plasma proteins were identified using MASCOT Daemon software v.2.4.0 and label-free quantification analysis was carried out by SCAFFOLD Q+ software v.4.0 using the Exponentially Modified Protein Abundance Index (emPAI) method. Functional classification of proteins was performed based on their genetic ontology terms using KOG. Functional cluster analysis was performed on DAVID. There were no differences in scrotal perimeter and physical semen characteristics between FIT and UNFIT groups of bulls. The percentage of sperm abnormalities was higher (p < 0.05) in the UNFIT group of bulls. A total of 297 proteins were identified for the two groups. There were a total of 11 differentially abundant proteins (p < 0.05), two of them more abundant in FIT bulls (Spermadhesin-1 and Ig gamma-1 chain C region) and nine in UNFIT bulls (Vasoactive intestinal peptide, Metalloproteinase inhibitor 2, Ig lambda-1 chain C regions, Protein FAM3C, Hemoglobin beta, Seminal ribonuclease, Spermadhesin 2, Seminal plasma protein BSP-30kDa, and Spermadhesin Z13). Spermadhesin-1 was the protein with the highest relative abundance (36.7%) in the seminal plasma among all bulls, corresponding to 47.7% for the FIT bulls and 25,7% for the UNFIT bulls. Posttranslational modification, protein turnover, and chaperones were the functional categories with the highest number of classified proteins. Protein functional annotation clusters were related to Phospholipid efflux, ATP binding, and chaperonin-containing T-complex. The differentially abundant proteins in the group of FIT bulls were related to sperm capacitation and protection against reactive species of oxygen. In contrast, differentially expressed proteins in the group of UNFIT bulls were related to motility inhibition, intramembrane cholesterol removal and oxidative stress. In conclusion, the proteomic profile of the seminal plasma of FIT bulls presents proteins with participation in several biological processes favorable to fertilization, while the proteins of the seminal plasma of UNFIT bulls indicate a series of alterations that can compromise the fertilizing capacity of the spermatozoa. In addition, the relative abundance of spermadhesin-1 found in the seminal plasma of young Nellore bulls could be studied as a reproductive parameter for selection.

Transcriptomic Analysis of the Rat Dorsal Root Ganglion After Fracture.

In fractures, pain signals are transmitted from the dorsal root ganglion (DRG) to the brain, and the DRG generates efferent signals to the injured bone to participate in the injury response. However, little is known about how this process occurs. We analyzed DRG transcriptome at 3, 7, 14, and 28 days after fracture. We identified the key pathways through KEGG and GO enrichment analysis. We then used IPA analysis to obtain upstream regulators and disease pathways. Finally, we compared the sequencing results with those of nerve injury to identify the unique transcriptome changes in DRG after fracture. We found that the first 14 days after fracture were the main repair response period, the 3rd day was the peak of repair activity, the 14th day was dominated by the stimulus response, and on the 28th day, the repair response had reached a plateau. ECM-receptor interaction, protein digestion and absorption, and the PI3K-Akt signaling pathway were most significantly enriched, which may be involved in repair regeneration, injury response, and pain transmission. Compared with the nerve injury model, DRG after fracture produced specific alterations related to bone repair, and the bone density function was the most widely activated bone-related function. Our results obtained some important genes and pathways in DRG after fracture, and we also summarized the main features of transcriptome function at each time point through functional annotation clustering of GO pathway, which gave us a deeper understanding of the role played by DRG in fracture.

Copy Number Variation Regions Differing in Segregation Patterns Span Different Sets of Genes.

Copy number variations regions (CNVRs) can be classified either as segregating, when found in both parents, and offspring, or non-segregating. A total of 65 segregating and 31 non-segregating CNVRs identified in at least 10 individuals within a dense pedigree of the Gochu Asturcelta pig breed was subjected to enrichment and functional annotation analyses to ascertain their functional independence and importance. Enrichment analyses allowed us to annotate 1018 and 351 candidate genes within the bounds of the segregating and non-segregating CNVRs, respectively. The information retrieved suggested that the candidate genes spanned by segregating and non-segregating CNVRs were functionally independent. Functional annotation analyses allowed us to identify nine different significantly enriched functional annotation clusters (ACs) in segregating CNVR candidate genes mainly involved in immunity and regulation of the cell cycle. Up to five significantly enriched ACs, mainly involved in reproduction and meat quality, were identified in non-segregating CNVRs. The current analysis fits with previous reports suggesting that segregating CNVRs would explain performance at the population level, whereas non-segregating CNVRs could explain between-individuals differences in performance.

Optic Nerve Head Gene Transcription Sequelae to a Single Elevated IOP Exposure Provides Insights Into Known Responses to Chronically Elevated IOP.

To clarify the optic nerve head (ONH) gene expression responses associated with a single, axon-damaging exposure to elevated IOP in relation to the composite cellular events previously identified in models of chronically elevated IOP. Anesthetized rats were exposed unilaterally to an 8-hour pulse-train controlled elevation of IOP (PT-CEI) at 60mm Hg, while others received normotensive CEI at 20mm Hg. ONH RNA was harvested at 0hours and 1, 2, 3, 7, and 10 days after either CEI and from naïve animals. RNA sequencing was performed to analyze ONH gene expression. DAVID Bioinformatics tools were used to identify significant functional annotation clusters. Gene function was compared between PT-CEI and two models of chronic ocular hypertension from the literature. The number of significantly changed genes peaked immediately (n = 1354) after PT-CEI (0hours). This was followed by a lull (<4 genes per time point) at 1 and 2days after PT-CEI. Gene activity increased again at 3 days (136 genes) and persisted at 7 (78 genes) and 10 (339 genes) days. Significant gene functional categories included an immediate upregulation of Defense Response at 0hours, followed by upregulation in Cell Cycle, a reduction in Axonal-related genes at 3 to 10 days, and upregulation of Immune Response-related genes at 10 days following PT-CEI. The most commonly upregulated gene expression across our PT-CEI study and two chronic models of ocular hypertension were cell cycle related. The PT-CEI model places in sequence ONH gene expression responses previously reported in models with chronically elevated IOP and may provide insights into their role in optic nerve damage.

SCUBE2 as a Marker of Resistance to Taxane-based Neoadjuvant Chemotherapy and a Potential Therapeutic Target in Breast Cancer.

Taxane-based neoadjuvant chemotherapy is the most common neoadjuvant approach in breast cancer, especially in human epidermal growth factor receptor 2 (HER2)-positive and triple-negative subtypes. However, chemoresistance is a problem in many patients, and success rates are low in estrogen receptor (ER)-positive breast cancer. The aim of this study was to identify predictive markers for resistance to taxane-based therapy, which may have a potential as therapeutic targets in breast cancer. Three comprehensive breast cancer Gene Expression Omnibus datasets were analyzed to identify differentially expressed genes (DEGs) in breast cancer patients resistant to taxane-based neoadjuvant chemotherapy. Functional annotation clustering and enrichment analysis were performed on the DEGs list. A protein-protein interaction network was established with the upregulated genes. The predictive value and the differential expression of the central genes were validated in the extensive ROC Plotter database. Seventeen upregulated genes were found which were associated with resistance to taxane-based neoadjuvant therapy and high connectivity in the network analysis. ESR1, CCND1, and SCUBE2 emerged as the top three key genes associated with resistance. SCUBE2 displayed a high predictive power comparable to ESR1, and better than CCND1, the two commonly accepted markers. The predictive ability of SCUBE2 was higher in ER-positive and HER2-positive breast cancers. These results suggest that SCUBE2 may be used as a predictive marker to guide decisions on neoadjuvant therapy. Emerging evidence about the role of SCUBE2 as a coreceptor involved in tumor progression and angiogenesis also suggests SCUBE2 as a potential therapeutic target. These points should be investigated in further studies.

Identification and Characterization of Copy Number Variations Regions in West African Taurine Cattle.

Simple SummaryNative West African (WA) taurine (Bos taurus) cattle are trypanotolerant; i.e., they have the ability to suppress the establishment of trypanosomes. Cattle trypanotolerance is a heritable trait—partially additive in nature—that can share mechanisms with tick resistance. Copy Number Variations (CNVs) are genomic alterations affecting gene structure, gene expression, and performance. However, the relationship between CNV regions and trypanotolerance and tick resistance in WA taurine cattle has not been approached thusfar. Here, we identify and characterize CNV regions in a sample of WA taurine cattle using WA zebu as an outgroup. The CNV regions identified spanned genes that are mainly involved in innate immunity. However, their relationship with genomic regions, previously reported to be associated with trypanotolerance and tick resistance, was not clear. Therefore, CNV alterations may not be the main genomic features underlying such traits.A total of 106 West African taurine cattle belonging to the Lagunaire breed of Benin (33), the N’Dama population of Burkina Faso (48), and N’Dama cattle sampled in Congo (25) were analyzed for Copy Number Variations (CNVs) using the BovineHDBeadChip of Illumina and two different CNV calling programs: PennCNV and QuantiSNP. Furthermore, 89 West African zebu samples (Bororo cattle of Mali and Zebu Peul sampled in Benin and Burkina Faso) were used as an outgroup to ensure that analyses reflect the taurine cattle genomic background. Analyses identified 307 taurine-specific CNV regions (CNVRs), covering about 56 Mb on all bovine autosomes. Gene annotation enrichment analysis identified a total of 840 candidate genes on 168 taurine-specific CNVRs. Three different statistically significant functional term annotation clusters (from ACt1 to ACt3) involved in the immune function were identified: ACt1 includes genes encoding lipocalins, proteins involved in the modulation of immune response and allergy; ACt2 includes genes encoding coding B-box-type zinc finger proteins and butyrophilins, involved in innate immune processes; and Act3 includes genes encoding lectin receptors, involved in the inflammatory responses to pathogens and B- and T-cell differentiation. The overlap between taurine-specific CNVRs and QTL regions associated with trypanotolerant response and tick-resistance was relatively low, suggesting that the mechanisms underlying such traits may not be determined by CNV alterations. However, four taurine-specific CNVRs overlapped with QTL regions associated with both traits on BTA23, therefore suggesting that CNV alterations in major histocompatibility complex (MHC) genes can partially explain the existence of genetic mechanisms shared between trypanotolerance and tick resistance in cattle. This research contributes to the understanding of the genomic features of West African taurine cattle.

Stress signalling and STAT1 activation characterize the keratinocytic gene expression pattern in Hidradenitis suppurativa.

The pathogenetic factors generating the innate immune signal necessary for T-cell activation, initiation and chronification of Hidradenitis suppurativa (HS, also known as Acne inversa) are still poorly understood. Emerging evidence suggests that a defective keratinocyte function critically contributes to HS disease development and progression. To elucidate the role of keratinocytes in HS lesion formation, we compared the transcriptomes of lesional and perilesional epidermis isolated from HS patients by RNA sequencing (RNA Seq). Pairwise-matched lesional and perilesional HS skin samples of five different donors were obtained and epidermal keratinocytes freshly isolated and processed for RNA extraction and RNA seq. Lesionally regulated genes were analysed by large-scale promoter analysis and functional annotation clustering to identify epidermally overrepresented transcription factor binding sites and functionally related gene groups. Results were experimentally validated with independent epidermal isolates of patient-matched lesional and perilesional HS skin employing qRT-PCR, cell culture, immunoblot and immunostaining. We show that HS is characterized by a strong epidermal stress state evident by a significant overrepresentation of an AP-1-driven gene signature and a substantial activation of the stress-activated cJun N-terminal kinase (JNK) pathway in lesional epidermis. Additionally, our data reveal a strong induction of STAT1 activation in lesional HS epidermis that likely results from IFNγ production and triggered expression of key inflammatory genes coordinating innate immune activation and the adaptive T-cell response in HS. Our data implicate a key role of stress signalling and JAK/STAT1 activation in disease progression of HS and suggest interference with JAK/STAT1 signalling as a potentially promising therapeutic approach for HS.

Posterior cingulate cortex reveals an expression profile of resilience in cognitively intact elders.

The posterior cingulate cortex, a key hub of the default mode network, underlies autobiographical memory retrieval and displays hypometabolic changes early in Alzheimer disease. To obtain an unbiased understanding of the molecular pathobiology of the aged posterior cingulate cortex, we performed RNA sequencing (RNA-seq) on tissue obtained from 26 participants of the Rush Religious Orders Study (11 males/15 females; aged 76–96 years) with a pre-mortem clinical diagnosis of no cognitive impairment and post-mortem neurofibrillary tangle Braak Stages I/II, III, and IV. Transcriptomic data were gathered using next-generation sequencing of RNA extracted from posterior cingulate cortex generating an average of 60 million paired reads per subject. Normalized expression of RNA-seq data was calculated using a global gene annotation and a microRNA profile. Differential expression (DESeq2, edgeR) using Braak staging as the comparison structure isolated genes for dimensional scaling, associative network building and functional clustering. Curated genes were correlated with the Mini-Mental State Examination and semantic, working and episodic memory, visuospatial ability, and a composite Global Cognitive Score. Regulatory mechanisms were determined by co-expression networks with microRNAs and an overlap of transcription factor binding sites. Analysis revealed 750 genes and 12 microRNAs significantly differentially expressed between Braak Stages I/II and III/IV and an associated six groups of transcription factor binding sites. Inputting significantly different gene/network data into a functional annotation clustering model revealed elevated presynaptic, postsynaptic and ATP-related expression in Braak Stages III and IV compared with Stages I/II, suggesting these pathways are integral for cognitive resilience seen in unimpaired elderly subjects. Principal component analysis and Kruskal–Wallis testing did not associate Braak stage with cognitive function. However, Spearman correlations between genes and cognitive test scores followed by network analysis revealed upregulation of classes of synaptic genes positively associated with performance on the visuospatial perceptual orientation domain. Upregulation of key synaptic genes suggests a role for these transcripts and associated synaptic pathways in cognitive resilience seen in elders despite Alzheimer disease pathology and dementia.

Functional genome-wide short hairpin RNA library screening identifies key molecules for extracellular vesicle secretion from microglia

SUMMARYActivated microglia release extracellular vesicles (EVs) as modulators of brain homeostasis and innate immunity. However, the molecules critical for regulating EV production from microglia are poorly understood. Here we establish a murine microglial cell model to monitor EV secretion by measuring the fluorescence signal of tdTomato, which is linked to tetraspanin CD63. Stimulation of tdTomato+ cells with ATP induces rapid secretion of EVs and a reduction in cellular tdTomato intensity, reflecting EV secretion. We generate a GFP+ tdTomato+ cell library expressing TurboGFP and barcoded short hairpin RNAs for genome-wide screening using next-generation sequencing. We identify Mcfd2, Sepp1, and Sdc1 as critical regulators of ATP-induced EV secretion from murine microglia. Small interfering RNA (siRNA-based) silencing of each of these genes suppresses lipopolysaccharide- and ATP-induced inflammasome activation, as determined by interleukin-1β release from primary cultured murine microglia. These molecules are critical for microglial EV secretion and are potential therapeutic targets for neuroinflammatory disorders.

MRNA expression analysis of the hippocampus in a vervet monkey model of fetal alcohol spectrum disorder

BackgroundFetal alcohol spectrum disorders (FASD) are common, yet preventable developmental disorders that stem from prenatal exposure to alcohol. This exposure leads to a wide array of behavioural and physical problems with a complex and poorly defined biological basis.Molecular investigations to date predominantly use rodent animal models, but because of genetic, developmental and social behavioral similarity, primate models are more relevant. We previously reported reduced cortical and hippocampal neuron levels in an Old World monkey (Chlorocebus sabaeus) model with ethanol exposure targeted to the period of rapid synaptogenesis and report here an initial molecular study of this model. The goal of this study was to evaluate mRNA expression of the hippocampus at two different behavioural stages (5 months, 2 years) corresponding to human infancy and early childhood.MethodsOffspring of alcohol-preferring or control dams drank a maximum of 3.5 g ethanol per kg body weight or calorically matched sucrose solution 4 days per week during the last 2 months of gestation. Total mRNA expression was measured with the Affymetrix GeneChip Rhesus Macaque Genome Array in a 2 × 2 study design that interrogated two independent variables, age at sacrifice, and alcohol consumption during gestation.Results and discussionStatistical analysis identified a preferential downregulation of expression when interrogating the factor ‘alcohol’ with a balanced effect of upregulation vs. downregulation for the independent variable ‘age’. Functional exploration of both independent variables shows that the alcohol consumption factor generates broad functional annotation clusters that likely implicate a role for epigenetics in the observed differential expression, while the variable age reliably produced functional annotation clusters predominantly related to development. Furthermore, our data reveals a novel connection between EFNB1 and the FASDs; this is highly plausible both due to the role of EFNB1 in neuronal development as well as its central role in craniofrontal nasal syndrome (CFNS). Fold changes for key genes were subsequently confirmed via qRT-PCR.ConclusionPrenatal alcohol exposure leads to global downregulation in mRNA expression. The cellular interference model of EFNB1 provides a potential clue regarding how genetically susceptible individuals may develop the phenotypic triad generally associated with classic fetal alcohol syndrome.

Differences in the Genomic Profiles of Immunoparalyzed and Nonimmunoparalyzed Children With Sepsis: A Pilot Study.

Sepsis-induced immunoparalysis represents a pathologic downregulation of leukocyte function shown to be associated with adverse outcomes, although its mechanisms remain poorly understood. Our goal was to compare genome-wide gene expression profiles of immunoparalyzed and nonimmunoparalyzed children with sepsis to identify genes and pathways associated with immunoparalysis. Prospective observational study. Twenty-six children with lower respiratory tract infection meeting criteria for sepsis, severe sepsis, or septic shock admitted to the PICU. Two tertiary care PICUs. None. Innate immune function was assayed ex vivo by measuring release of tumor necrosis factor-α from whole blood after incubation with lipopolysaccharide for 4 hours. Immunoparalysis was defined as a tumor necrosis factor-α production capacity less than 200 pg/mL. Ten of the 26 children were immunoparalyzed. There were 17 significant differentially expressed genes when comparing genome-wide gene expression profiles of immunoparalyzed and nonimmunoparalyzed children (false discovery rate < 0.05). Nine genes showed increased expression in immunoparalyzed children (+1.5- to +8.8-fold change). Several of these dampen the immune system. Eight showed decreased expression in immunoparalyzed children (-1.7- to -3.9-fold change), several of which are involved in early regulation and activation of immune function. Functional annotation clustering using differentially expressed genes with p value of less than 0.05 showed three clusters related to immunity with significant enrichment scores (2.2-4.5); the most significant gene ontology terms in these clusters were antigen processing and presentation and negative regulation of interleukin-6 production. Network analysis identified potential protein interactions that may be involved in the development of immunoparalysis in children. In this exploratory analysis, immunoparalyzed children with sepsis showed increased expression of genes that dampen the immune system and decreased expression of genes involved in regulation and activation of the immune system. Analysis also implicated other proteins as potentially having as yet unidentified roles in the development of immunoparalysis.

The Novel microRNA Rno-miR-686-3p Is Associated with the Ischaemic Penumbra

Introduction: We explored microRNA (miRNA) profiles correlated with the penumbra in three different phases of ischaemic stroke, using a permanent middle cerebral artery occlusion (p-MCAO) rat model. Materials and Methods: A 2-mm coronal section was cut from the optic chiasma in the caudal direction, and the penumbra was located in the area between a longitudinal line approximately 2 mm from the midline and a transverse diagonal line at the “2-o’clock” position. Total RNA was extracted from tissue specimens and peripheral blood samples, followed by deep sequencing analysis. Results: We identified nine novel miRNA candidates in tissues and evaluated their expression levels using real-time quantitative polymerase chain reaction. In situ hybridization was conducted to assess miRNA localization in the brain. Of these nine candidates, we identified and characterized a novel miRNA, rno-miR-686-3p, which was localized in cell nuclei of the cortex, and associated with the penumbra. rno-miR-686-3p was downregulated at 1 (p = 0.042), 3 (p = 0.032), and 4 h (p = 0.007) post-p-MCAO in the penumbra. A total of 297 potential target genes were predicted. Moreover, functional annotation clustering and pathway enrichment analysis predicted that rno-miR-686-3p participates in transcriptional regulation and the Wnt and cyclic adenosine monophosphate (cAMP) signalling pathways. Conclusion: rno-miR-686-3p is a novel miRNA associated with the ischaemic penumbra that is implicated in transcriptional regulation and modulation of the Wnt and cAMP signalling pathways. Furthermore, it may serve as a possible new biomarker with potential value for detecting the existence of the penumbra.

Sorting nexin 24 is required for α-granule biogenesis and cargo delivery in megakaryocytes.

Germline defects affecting the DNA-binding domain of the transcription factor FLI1 are associated with a bleeding disorder that is characterized by the presence of large, fused α-granules in platelets. We investigated whether the genes showing abnormal expression in FLI1-deficient platelets could be involved in platelet α-granule biogenesis by undertaking transcriptome analysis of control platelets and platelets harboring a DNA-binding variant of FLI1. Our analysis identified 2,276 transcripts that were differentially expressed in FLI1-deficient platelets. Functional annotation clustering of the coding transcripts revealed significant enrichment for gene annotations relating to protein transport, and identified Sorting nexin 24 (SNX24) as a candidate for further investigation. Using an induced pluripotent stem cell-derived megakaryocyte model, SNX24 expression was found to be increased during the early stages of megakaryocyte differentiation and downregulated during proplatelet formation, indicating tight regulatory control during megakaryopoiesis. CRISPR-Cas9 mediated knockout (KO) of SNX24 led to decreased expression of immature megakaryocyte markers, CD41 and CD61, and increased expression of the mature megakaryocyte marker CD42b (P=0.0001), without affecting megakaryocyte polyploidisation, or proplatelet formation. Electron microscopic analysis revealed an increase in empty membrane-bound organelles in SNX24 KO megakaryocytes, a reduction in α-granules and an absence of immature and mature multivesicular bodies, consistent with a defect in the intermediate stage of α-granule maturation. Co-localization studies showed that SNX24 associates with each compartment of α-granule maturation. Reduced expression of CD62P and VWF was observed in SNX24 KO megakaryocytes. We conclude that SNX24 is required for α-granule biogenesis and intracellular trafficking of α-granule cargo within megakaryocytes.