RNA Fluorescence In Situ Hybridization Research Articles

Burst-like transcription of MYH7, allelic and contractile imbalance already in early stage hiPSC-cardiomyocytes indicate these as pathogenic factors in Hypertrophic Cardiomyopathy

Abstract Background Hypertrophic Cardiomyopathy (HCM) is caused by heterozygous mutations in sarcomeric proteins, which can cause hyper- or hypocontractiliy of cardiomyocytes. Previously we also observed highly variable force generation (contractile imbalance) among individual cardiomyocytes of HCM-patients with myosin (MYH7) or myosin-binding-protein-C mutations (MYBPC3), ranging from normal to highly altered values. Contractile imbalance is presumably caused by stochastic, burst-like transcription of mutant and wildtype allele, which induces unequal ratios of mutant vs. wildtype mRNA among individual cardiomyocytes. Variable force generation most likely is the result of also unequal fractions of mutated protein from cell to cell. Aim With this study we aimed to examine whether in addition to the effects of the mutation on sarcomere function, also allelic and contractile imbalance already exist at the beginning of disease development or whether both result from disease-related alterations in symptomatic HCM-patients. Methods and Results We studied this in patient-derived human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) with MYH7-mutation R723G as model for an early disease stage. These early, fetal-like cardiomyocytes developed typical HCM-related features like hypertrophy and increased myofibrillar disarray compared to WT-hiPSC-CMs. Calcium sensitivity was reduced, twitch kinetics were slowed down. To test whether MYH7 in these early-stage hiPSC-CMs also is transcribed in bursts or continuously, we performed RNA-fluorescence in situ hybridization (RNA-FISH). Nuclei without, with one and with two or more active transcription sites were observed which indicates stochastic, burst-like and independent transcription of the two MYH7-alleles. Ratios of mRNA from both alleles were quantified in individual cardiomyocytes by allele-specific single cell RT-PCR. We found highly variable ratios of mutated vs. wildtype mRNA among individual cardiomyocytes, similar to HCM-patient’s cardiac tissue, indicating unequal expression of mutant and wildtype mRNA from cell-to-cell. Furthermore, functional measurements on myofibrils from R723G-hiPSC-CMs revealed substantial variability in force generation at physiological calcium, compared to much smaller heterogeneity among WT-hiPSC-CMs. In addition, variability of twitch kinetics of intact hiPSC-CMs was also substantially increased among R723G- compared to WT-hiPSC-CMs. Altogether, this suggests that functional heterogeneity results from burst-like transcription in heterozygous HCM cardiomyocytes. Conclusions Our results in HCM-patient derived hiPSC-cardiomyocytes with a fetal-like developmental stage suggest that allelic and contractile imbalance among individual cardiomyocytes together with the mutation are present at the beginning of the disease. Thus, they most likely are exacerbating factors that contribute development of HCM hallmarks.

ImputeHiFI: An Imputation Method for Multiplexed DNA FISH Data by Utilizing Single-Cell Hi-C and RNA FISH Data.

Although multiplexed DNA fluorescence in situ hybridization (FISH) enables tracking the spatial localization of thousands of genomic loci using probes within individual cells, the high rates of undetected probes impede the depiction of 3D chromosome structures. Current data imputation methods neither utilize single-cell Hi-C data, which elucidate 3D genome architectures using sequencing nor leverage multimodal RNA FISH data that reflect cell-type information, limiting the effectiveness of these methods in complex tissues such as the mouse brain. To this end, a novel multiplexed DNA FISH imputation method named ImputeHiFI is proposed, which fully utilizes the complementary structural information from single-cell Hi-C data and the cell type signature from RNA FISH data to obtain a high-fidelity and complete spatial location of chromatin loci. ImputeHiFI enhances cell clustering, compartment identification, and cell subtype detection at the single-cell level in the mouse brain. ImputeHiFI improves the recognition of cell-type-specific loops in three high-resolution datasets. In short, ImputeHiFI is a powerful tool capable of imputing multiplexed DNA FISH data from various resolutions and imaging protocols, facilitating studies of 3D genome structures and functions.

Use of high-resolution fluorescence in situ hybridization for fast and robust detection of SARS-CoV-2 RNAs

Early, rapid, and accurate diagnostic tests play critical roles not only in the identification/management of individuals infected by SARS-CoV-2, but also in fast and effective public health surveillance, containment, and response. Our aim has been to develop a fast and robust fluorescence in situ hybridization (FISH) detection method for detecting SARS-CoV-2 RNAs by using an HEK 293 T cell culture model. At various times after being transfected with SARS-CoV-2 E and N plasmids, HEK 293 T cells were fixed and then hybridized with ATTO-labeled short DNA probes (about 20 nt). At 4 h, 12 h, and 24 h after transfection, SARS-CoV-2 E and N mRNAs were clearly revealed as solid granular staining inside HEK 293 T cells at all time points. Hybridization time was also reduced to 1 h for faster detection, and the test was completed within 3 h with excellent results. In addition, we have successfully detected 3 mRNAs (E mRNA, N mRNA, and ORF1a (−) RNA) simultaneously inside the buccal cells of COVID-19 patients. Our high-resolution RNA FISH might significantly increase the accuracy and efficiency of SARS-CoV-2 detection, while significantly reducing test time. The method can be conducted on smears containing cells (e.g., from nasopharyngeal, oropharyngeal, or buccal swabs) or smears without cells (e.g., from sputum, saliva, or drinking water/wastewater) for detecting various types of RNA viruses and even DNA viruses at different timepoints of infection.

Allele-level visualization of transcription and chromatin by high-throughput imaging

The spatial arrangement of the genome within the nucleus is a pivotal aspect of cellular organization and function with implications for gene expression and regulation. While all genome organization features, such as loops, domains, and radial positioning, are nonrandom, they are characterized by a high degree of single-cell variability. Imaging approaches are ideally suited to visualize, measure, and study single-cell heterogeneity in genome organization. Here, we describe two methods for the detection of DNA and RNA of individual gene alleles by fluorescence in situ hybridization (FISH) in a high-throughput format. We have optimized combined DNA/RNA FISH approaches either using simultaneous or sequential detection of DNA and nascent RNA. These optimized DNA and RNA FISH protocols were implemented in a 384-well plate format alongside automated image and data analysis and enable accurate detection of individual gene alleles and their gene expression status across a large cell population. We successfully visualized MYC and EGFR DNA and nascent RNA with allele-level resolution in multiple cell types, and we determined the radial position of active and inactive MYC and EGFR alleles. These optimized DNA/RNA detection approaches are versatile and sensitive tools for mapping of chromatin features and gene activity at the single-allele level and at high throughput.

Whole transcriptome profiling reveals a lncMDP1 that regulates myogenesis by adsorbing miR-301a-5p targeting CHAC1

Myoblast proliferation and differentiation are essential for skeletal muscle development. In this study, we generated the expression profiles of mRNAs, long noncoding RNAs (lncRNAs), and microRNAs (miRNAs) in different developmental stages of chicken primary myoblasts (CPMs) using RNA sequencing (RNA-seq) technology. The dual luciferase reporter system was performed using chicken embryonic fibroblast cells (DF-1), and functional studies quantitative real-time polymerase chain reaction (qPCR), cell counting kit-8 (CCK-8), 5-Ethynyl-2′-deoxyuridine (EdU), flow cytometry cycle, RNA fluorescence in situ hybridization (RNA-FISH), immunofluorescence, and western blotting assay. Our research demonstrated that miR-301a-5p had a targeted binding ability to lncMDP1 and ChaC glutathione-specific gamma-glutamylcyclotransferase 1 (CHAC1). The results revealed that lncMDP1 regulated the proliferation and differentiation of myoblasts via regulating the miR-301a-5p/CHAC1 axis, and CHAC1 promotes muscle regeneration. This study fulfilled the molecular regulatory network of skeletal muscle development and providing an important theoretical reference for the future improvement of chicken meat performance and meat quality.

Identification of a novel de novo mutation in SOX4 for syndromic tooth agenesis.

Coffin-Siris Syndrome (CSS) is a congenital disorder characterized by delayed growth, dysmorphic facial features, hypoplastic nails and phalanges of the fifth digit, and dental abnormalities. Tooth agenesis has been reported in CSS patients, but the mechanisms regulating this syndromic tooth agenesis remain largely unknown. This study aims to identify the pathogenic mutation of CSS presenting tooth genesis and explore potential regulatory mechanisms. We utilized whole-exome sequencing to identify variants in a CSS patient, followed by Sanger validation. In silico analysis including conservation analysis, pathogenicity predictions, and 3D structural assessments were carried out. Additionally, single-cell RNA sequencing and fluorescence in situ hybridization (FISH) were applied to explore the spatio-temporal expression of Sox4 expression during murine tooth development. Weighted Gene Co-expression Network Analysis (WGCNA) was employed to examine the functional role of SOX4. A novel de novo SOX4 missense mutation (c.1255C > G, p.Leu419Val) was identified in a Chinese CSS patient exhibiting tooth agenesis. Single-cell RNA sequencing and FISH further verified high expression of Sox4 during murine tooth development, and WGCNA confirmed its central role in tooth development pathways. Enriched functions included cell-substrate junctions, focal adhesion, and RNA splicing. Our findings link a novel SOX4 mutation to syndromic tooth agenesis in CSS. This is the first report of SOX4 missense mutation causing syndromic tooth agenesis. This study not only enhances our understanding of the pathogenic mutation for syndromic tooth agenesis but also provides genetic diagnosis and potential therapeutic insights for syndromic tooth agenesis.

Long non-coding RNA MLLT4 antisense RNA 1 induces autophagy to inhibit tumorigenesis of cervical cancer through modulating the myosin-9/ATG14 axis

The regulatory mechanism of long non-coding RNAs (lncRNAs) in autophagy is as yet not well established. In this research, we show that the long non-coding RNA MLLT4 antisense RNA 1 (lncRNA MLLT4-AS1) is induced by the MTORC inhibitor PP242 and rapamycin in cervical cells. Overexpression of MLLT4-AS1 promotes autophagy and inhibits tumorigenesis and the migration of cervical cancer cells, whereas knockdown of MLLT4-AS1 attenuates PP242-induced autophagy. Mass spectrometry, RNA fluorescence in situ hybridization (RNA-FISH), and immunoprecipitation assays were performed to identify the direct interactions between MLLT4-AS1 and other associated targets, such as myosin-9 and autophagy-related 14(ATG14). MLLT4-AS1 was upregulated by H3K27ac modification with PP242 treatment, and knockdown of MLLT4-AS1 reversed autophagy by modulating ATG14 expression. Mechanically, MLLT4-AS1 was associated with the myosin-9 protein, which further promoted the transcription activity of the ATG14 gene. In conclusion, we demonstrated that MLLT4-AS1 acts as a potential tumor suppressor in cervical cancer by inducing autophagy, and H3K27ac modification-induced upregulation of MLLT4-AS1 could cause autophagy by associating with myosin-9 and promoting ATG14 transcription.

Hsa_circ_0079875 functions as a competitive endogenous RNA to promote hepatocellular carcinoma progression

ABSTRACT Circular RNA (circRNA) can influence the development of hepatocellular carcinoma (HCC) as a competitive endogenous RNA (ceRNA). However, there are still many circRNAs whose functions are unknown. Our research explores the role of a novel circRNA, hsa_circ_0079875, in HCC. The expression of hsa_circ_0079875 in HCC was verified by next-generation sequencing, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and fluorescence in situ hybridization (FISH). The distribution of hsa_circ_0079875 in HCC cells was investigated by RNA subcellular isolation and FISH assays. The functional effects on HCC proliferation, invasion, migration, cell cycle, and apoptosis were verified by overexpression and knockdown of hsa_circ_0079875. Moreover, xenograft mouse models and immunohistochemistry experiments were used to assess the function of hsa_circ_0079875 in vivo. Hsa_circ_0079875 was up-regulated in HCC tissues and mainly distributed in the cytoplasm. Higher hsa_circ_0079875 leads to larger tumor tissue, more microvascular invasion(MVI) and higher AFP levels, which in turn leads to a poor prognosis. Overexpression of hsa_circ_0079875 can promote the proliferation, migration, and invasion of HCC cells and inhibit apoptosis in vitro and in vivo. Knocking down hsa_circ_0079875 has the opposite effect. Sequencing and biological information predicted the target miRNA and mRNA of hsa_circ_0079875. Further bioinformatics and clinical correlation analysis revealed that hsa_circ_0079875 promote the malignant biological behaviors of HCC through hsa_circ_0079875/miR-519d-59/NRAS ceRNA net. Therefore, hsa_circ_0079875 can be a potential prognostic marker and therapeutic target for HCC.

High-Throughput RNA-HCR-FISH Detection of Endogenous Pre-mRNA Splice Variants.

RNA-fluorescence in situ hybridization (RNA-FISH) is an essential and widely used tool for visualizing RNA molecules in intact cells. Recent advances have increased RNA-FISH sensitivity, signal detection efficiency, and throughput. However, detection of endogenous mRNA splice variants has been challenging due to the limits of visualization of RNA-FISH fluorescence signals and due to the limited number of RNA-FISH probes per target. HiFENS (high-throughput FISH detection of endogenous pre-mRNA splicing isoforms) is a method that enables visualization and relative quantification of mRNA splice variants at single-cell resolution in an automated high-throughput manner. HiFENS incorporates HCR (hybridization chain reaction) signal amplification strategies to enhance the fluorescence signal generated by low abundance transcripts or a small number of FISH probes targeting short stretches of RNA, such as single exons. The technique offers a significant advance in high-throughput FISH-based RNA detection and provides a powerful tool that can be used as a readout in functional genomics screens to discover and dissect cellular pathways regulating gene expression and alternative pre-mRNA splicing events.

RNA fluorescence in situ hybridization (FISH) as a method to visualize bacterial colonization in the C. elegans gut.

Caenorhabditis elegans is an excellent model to study host-microbe interactions as it is easy to visualize bacterial presence in their intestine. However, previous studies have shown that utilizing transgenic, fluorescent protein-expressing bacteria is not a reliable method to distinguish living bacteria from dead bacteria in the lumen of C. elegans . In this study, we compared methods for visualizing bacterial presence within the C. elegans intestine and found that RNA f luorescent i n s itu h ybridization (RNA FISH) could distinguish the difference between intact and dead bacteria. Thus, we propose RNA FISH as the preferred method to visualize live bacterial presence in the intestines of C. elegans prior to fixation.

Multiplexed Immunofluorescence and Single-Molecule RNA Fluorescence In Situ Hybridization in Mouse Skeletal Myofibers.

RNA fluorescence in situ hybridization (FISH) is a powerful method to determine the abundance and localization of mRNA molecules in cells. While modern RNA FISH techniques allow quantification at single molecule resolution, most methods are optimized for mammalian cell culture and are not easily applied to in vivo tissue settings. Single-molecule RNA detection in skeletal muscle cells has been particularly challenging due to the thickness and high autofluorescence of adult muscle tissue and a lack of in vitro models for mature muscle cells (myofibers). Here, we present a method for isolation of adult myofibers from mouse skeletal muscle and detection of single mRNA molecules and proteins using multiplexed RNA FISH and immunofluorescence.

Single-Molecule Visualization of Bunyavirus Genome Segments Using Fluorescence In Situ Hybridization.

The genome of most bunyaviruses is divided over three (S, M, and L) single-stranded RNA segments of negative polarity. The three viral RNA segments are essential to establish a productive infection. RNA fluorescence in situ hybridization (FISH) enables the detection, localization, and quantification of RNA molecules at single-molecule resolution. This chapter describes an RNA FISH method to directly visualize individual segment-specific bunyavirus RNAs in fixed infected cells and in mature virus particles, using Rift Valley fever virus as an example. Imaging of bunyavirus RNA segments is a valuable experimental tool to investigate fundamental aspects of the bunyavirus life cycle, such as virus replication, genome packaging, and virion assembly, among others.

Combined 3D DNA FISH, Single-Molecule RNA FISH, and Immunofluorescence.

Nuclear architecture is a potential regulator of gene expression in eukaryotic cells. Studies connecting nuclear architecture to gene expression are often population-averaged and do not report on the cell-level heterogeneity in genome organization and associated gene expression. In this report we present a simple way to combine fluorescence in situ hybridization (FISH)-based detection of DNA, with single-molecule RNA FISH (smFISH) and immunofluorescence (IF), while also preserving the three-dimensional (3D) nuclear architecture of a cell. Recently developed smFISH techniques enable the detection of individual RNA molecules; while using 3D DNA FISH, copy numbers and positions of genes inside the nucleus can be interrogated without interfering with 3D nuclear architecture. Our method to combine 3D DNA FISH with smFISH and IF enables a unique quantitative handle on the central dogma of molecular biology.

The upregulation of circFoxp1 influences keloid by promoting cell proliferation.

As a result of abnormal wound healing in susceptible individuals, keloids are characterized by hyperproliferation of fibroblasts and excessive deposition of the extracellular matrix (ECM). Current surgical and therapeutic modalities provide limited satisfactory results. Circular ribonucleic acids (circRNAs) play a crucial role in the pathogenesis of various fibrotic diseases, but the potential biological function and expression profile of circRNAs in keloid formation remain unknown. In this study, we explored the function of circFoxp1 on keloid formation. Methods: Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) results revealed that circFoxp1 expression was higher in the keloid tissues. Furthermore, RNA-fluorescence in situ hybridization (RNA-FISH) and RNAscope illustrated that circFoxp1 was present in the cytoplasm. Subsequent cellular experiments demonstrated that circFoxp1 overexpression enhanced proliferation, migration, and ECM deposition. In addition, apoptosis was inhibited. Cell proliferation, inflammatory response, and oxidative phosphorylation of fibroblasts were also observed by RNA sequencing and were closely related to scar formation. The therapeutic potential of circFoxp1 was investigated by establishing keloid implantation models. In vivo, circFoxp1 can promote fibroblast proliferation and ECM deposition. RNA pull-down and western blot assays verified the interaction of circFoxp1 with RACK1. The present study reveals that circFoxp1 contributes to the pathological hyperplasia of keloid, which may improve inflammation and cell proliferation. Our data indicate that circFoxp1 may serve as a novel, promising therapeutic target, presenting a new avenue for understanding the underlying pathogenesis of keloid.

A hybrid RNA FISH immunofluorescence protocol on Drosophila polytene chromosomes

ObjectivesInvestigating protein-DNA interactions is imperative to understanding fundamental concepts such as cell growth, differentiation, and cell development in many systems. Sequencing techniques such as ChIP-seq can yield genome-wide DNA binding profiles of transcription factors; however this assay can be expensive, time-consuming, may not be informative for repetitive regions of the genome, and depend heavily upon antibody suitability. Combining DNA fluorescence in situ hybridization (FISH) with immunofluorescence (IF) is a quicker and inexpensive approach which has historically been used to investigate protein-DNA interactions in individual nuclei. However, these assays are sometimes incompatible due to the required denaturation step in DNA FISH that can alter protein epitopes, hindering primary antibody binding. Additionally, combining DNA FISH with IF may be challenging for less experienced trainees. Our goal was to develop an alternative technique to investigate protein-DNA interactions by combining RNA FISH with IF.ResultsWe developed a hybrid RNA FISH-IF protocol for use on Drosophila melanogaster polytene chromosome spreads in order to visualize colocalization of proteins and DNA loci. We demonstrate that this assay is sensitive enough to determine if our protein of interest, Multi sex combs (Mxc), localizes to single-copy target transgenes carrying histone genes. Overall, this study provides an alternative, accessible method for investigating protein-DNA interactions at the single gene level in Drosophila melanogaster polytene chromosomes.

Monte Carlo samplers for efficient network inference.

Accessing information on an underlying network driving a biological process often involves interrupting the process and collecting snapshot data. When snapshot data are stochastic, the data's structure necessitates a probabilistic description to infer underlying reaction networks. As an example, we may imagine wanting to learn gene state networks from the type of data collected in single molecule RNA fluorescence in situ hybridization (RNA-FISH). In the networks we consider, nodes represent network states, and edges represent biochemical reaction rates linking states. Simultaneously estimating the number of nodes and constituent parameters from snapshot data remains a challenging task in part on account of data uncertainty and timescale separations between kinetic parameters mediating the network. While parametric Bayesian methods learn parameters given a network structure (with known node numbers) with rigorously propagated measurement uncertainty, learning the number of nodes and parameters with potentially large timescale separations remain open questions. Here, we propose a Bayesian nonparametric framework and describe a hybrid Bayesian Markov Chain Monte Carlo (MCMC) sampler directly addressing these challenges. In particular, in our hybrid method, Hamiltonian Monte Carlo (HMC) leverages local posterior geometries in inference to explore the parameter space; Adaptive Metropolis Hastings (AMH) learns correlations between plausible parameter sets to efficiently propose probable models; and Parallel Tempering takes into account multiple models simultaneously with tempered information content to augment sampling efficiency. We apply our method to synthetic data mimicking single molecule RNA-FISH, a popular snapshot method in probing transcriptional networks to illustrate the identified challenges inherent to learning dynamical models from these snapshots and how our method addresses them.

Dysregulation of a lncRNA within the TNFRSF10A locus activates cell death pathways

TNFRSF10A (tumor necrosis factor receptor superfamily member 10A) encodes a cell surface receptor protein involved in apoptotic, necroptotic, and inflammatory pathways. Dysregulation of TNFRSF10A has been implicated in sensitization to apoptosis and to the development of multiple diseases, yet little is known of the AC100861.1 long noncoding RNA (lncRNA) that lies head-to-head with TNFRSF10A. Given its genomic positioning, we sought to investigate the function of AC100861.1, focusing on its potential relationship with TNFRSF10A and the role it may play in death receptor signaling. Using knockdown and overexpression strategies, we probed cell viability and examined transcript and protein-level changes in key genes involved in apoptosis, necroptosis, and inflammation. Decreased cell viability was observed upon TNFRSF10A overexpression, regardless of whether the cells were subjected to the chemical stressor tunicamycin. Similarly, overexpression of AC100861.1 led to increased cell death, with a further increase observed under conditions of cellular stress. Knockdown of TNFRSF10A increased cell death only when the cells were stressed, and AC100861.1 knockdown exhibited no effect on cell death. Neither knockdown nor overexpression of either of these genes greatly affected the expression of the other. Manipulating AC100861.1, however, led to marked changes in the expression of genes involved in necroptosis and inflammatory cell-signaling pathways. Additionally, RNA fluorescence in situ hybridization (RNA-FISH) revealed that the AC100861.1 transcript is localized primarily to the cytoplasm. Together, these data suggest that AC100861.1 may have a role in regulating necroptotic and inflammatory signaling pathways and that this function is separate from changes in TNFRSF10A expression. Given the importance of this genomic locus for cell survival, these data provide insight into the function of a poorly understood lncRNA with potential implications regarding disease pathology and treatment.

RNA Fluorescence In Situ Hybridization for Long Non-Coding RNA Localization in Human Osteosarcoma Cells.

The important roles of long non-coding RNAs (lncRNAs) in cancer have been studied, such as regulating the proliferation, epithelial-mesenchymal transition (EMT), migration, infiltration, and autophagy of cancer cells. Localization detection of lncRNAs in cells can provide insight into their functions. By designing the lncRNA-specific antisense chain sequence followed by labeling with fluorescent dyes, RNA fluorescence in situ hybridization (FISH) can be applied to detect the cellular localization of lncRNAs. Together with the development of microscopy, the RNA FISH techniques now even allow for visualization of the poorly expressed lncRNAs. This method can not only detect the localization of lncRNAs alone, but also detect the colocalization of other RNAs, DNA, or proteins by using double-color or multicolor immunofluorescence. Here, we have included the detailed experimental operation procedure and precautions of RNA FISH by using lncRNA small nucleolar RNA host gene 6 (SNHG6) in human osteosarcoma cells (143B) as an example, to provide a reference for researchers who want to perform RNA FISH experiments, especially lncRNA FISH.

Single-cell detection of primary transcripts, their genomic loci and nuclear factors by 3D immuno-RNA/DNA FISH in T cells.

Over the past decades, it has become increasingly clear that higher order chromatin folding and organization within the nucleus is involved in the regulation of genome activity and serves as an additional epigenetic mechanism that modulates cellular functions and gene expression programs in diverse biological processes. In particular, dynamic allelic interactions and nuclear locations can be of functional importance during the process of lymphoid differentiation and the regulation of immune responses. Analyses of the proximity between chromatin and/or nuclear regions can be performed on populations of cells with high-throughput sequencing approaches such as chromatin conformation capture ("3C"-based) or DNA adenine methyltransferase identification (DamID) methods, or, in individual cells, by the simultaneous visualization of genomic loci, their primary transcripts and nuclear compartments within the 3-dimensional nuclear space using Fluorescence In Situ Hybridization (FISH) and immunostaining. Here, we present a detailed protocol to simultaneously detect nascent RNA transcripts (3D RNA FISH), their genomic loci (3D DNA FISH) and/or their chromosome territories (CT paint DNA FISH) combined with the antibody-based detection of various nuclear factors (immunofluorescence). We delineate the application and effectiveness of this robust and reproducible protocol in several murine T lymphocyte subtypes (from differentiating thymic T cells, to activated splenic and peripheral T cells) as well as other murine cells, including embryonic stem cells, B cells, megakaryocytes and macrophages.

PD02-08 ESR1+ LUMINAL EPITHELIAL CELLS DRIVE THE PROSTATE GROWTH AND SURVIVAL IN THE ABSENCE OF SRD5A2

You have accessJournal of UrologyCME1 Apr 2023PD02-08 ESR1+ LUMINAL EPITHELIAL CELLS DRIVE THE PROSTATE GROWTH AND SURVIVAL IN THE ABSENCE OF SRD5A2 Christina Sharkey, Xingbo Long, Ra'ad Al-Faouri, Aria F. Olumi, and Zongwei Wang Christina SharkeyChristina Sharkey More articles by this author , Xingbo LongXingbo Long More articles by this author , Ra'ad Al-FaouriRa'ad Al-Faouri More articles by this author , Aria F. OlumiAria F. Olumi More articles by this author , and Zongwei WangZongwei Wang More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003219.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Steroid 5α reductase 2 (SRD5A2) is the predominant enzyme responsible for prostatic development and growth. 5α reductase inhibitors (5ARI) are the only class of benign prostate hyperplasia-related medications that reduce prostate size. However, why the patients respond variably to 5ARI therapies is still largely unknown. We previously demonstrated that 30% of adult human prostatic tissues do not express the SRD5A2 gene and protein via epigenetic modifications. We established a SRD5A2 null (Srd5a2-/-) mouse model and through single cell RNA sequencing, we identified LE2, a sub-cell population of ESR1+ luminal epithelial that is upregulated in Srd5a2-/- mice. Our goal in this study is to characterize the spatial expression of LE2 markers and its functional phenotype when SRD5A2 is absent. METHODS: Homozygous Srd5a2-/- mice and littermate control heterozygous SRD5A2+/- mice were generated and differentially expressed gene profiles of LE2 were obtained from single-cell RNA sequencing (scRNA seq). Spatial expression of LE2 markers was evaluated by RNA fluorescence in-situ hybridization (RNA-FISH). Cell proliferation was detected by Ki67 and BrdU staining. The Cell Death and ER signaling pathways were evaluated with RT2 PCR profiler arrays (84 genes per array) and downstream signaling pathways were analyzed by western blot. Prostate biopsies from the clinical trial of 5ARI for Medical Therapy of Prostatic Symptoms (MTOPS) were used for immunohistochemistry. RESULTS: The prostate weight of Srd5a2-/- mice was significantly decreased compared to Srd5a2+/- littermate control mice (p<0.001). The prostate cell proliferation was suppressed in Srd5a2-/- mice (p=0.05). The cell death signaling akt1, caspase 7, caspase 9, and ER target genes cyp1a1 and vegfa were downregulated (p<0.05). On the other hand, in the anterior lobe of prostate of Srd5a2-/- mice, the cell proliferation was higher than that in control. scRNA seq showed that ESR1 was expressed mainly in the prostate anterior lobe and the number of ESR1+ LE2 cells was significantly increased upon SRD5A2 absence. This was confirmed by RNA-FISH using the probes of LE2 cell markers ESR1 and PVT1. Co-staining of LE2 cell markers ESR1 and PKCa in prostate biopsies of MTOPS further confirmed the existence of an equivalent LE2 cell population in the human prostate with BPH. CONCLUSIONS: Our data demonstrate that LE2, the subpopulation of prostate cells may play an important role in alternative pathways for prostate growth and survival in absence of SRD5A2 and androgen deprivation. Understanding the underlying androgen-independent pathways contributing to prostate growth can help identify novel therapeutic targets for the management of prostatic diseases. Source of Funding: NIH/R01 DK124502 © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e71 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Christina Sharkey More articles by this author Xingbo Long More articles by this author Ra'ad Al-Faouri More articles by this author Aria F. Olumi More articles by this author Zongwei Wang More articles by this author Expand All Advertisement PDF downloadLoading ...