Transcription-AustinPub Date : 2023-06-01Epub Date: 2024-01-23DOI: 10.1080/21541264.2023.2286761
Zdenek Andrysik, Micah G Donovan
{"title":"RNA visualization and single-cell transcriptomics: methods and applications.","authors":"Zdenek Andrysik, Micah G Donovan","doi":"10.1080/21541264.2023.2286761","DOIUrl":"10.1080/21541264.2023.2286761","url":null,"abstract":"","PeriodicalId":47009,"journal":{"name":"Transcription-Austin","volume":" ","pages":"89-91"},"PeriodicalIF":3.6,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10807466/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138478956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Transcription-AustinPub Date : 2023-06-01Epub Date: 2023-04-12DOI: 10.1080/21541264.2023.2199669
Alan Gerber, Sander van Otterdijk, Frank J Bruggeman, Evelina Tutucci
{"title":"Understanding spatiotemporal coupling of gene expression using single molecule RNA imaging technologies.","authors":"Alan Gerber, Sander van Otterdijk, Frank J Bruggeman, Evelina Tutucci","doi":"10.1080/21541264.2023.2199669","DOIUrl":"10.1080/21541264.2023.2199669","url":null,"abstract":"<p><p>Across all kingdoms of life, gene regulatory mechanisms underlie cellular adaptation to ever-changing environments. Regulation of gene expression adjusts protein synthesis and, in turn, cellular growth. Messenger RNAs are key molecules in the process of gene expression. Our ability to quantitatively measure mRNA expression in single cells has improved tremendously over the past decades. This revealed an unexpected coordination between the steps that control the life of an mRNA, from transcription to degradation. Here, we provide an overview of the state-of-the-art imaging approaches for measurement and quantitative understanding of gene expression, starting from the early visualizations of single genes by electron microscopy to current fluorescence-based approaches in single cells, including live-cell RNA-imaging approaches to FISH-based spatial transcriptomics across model organisms. We also highlight how these methods have shaped our current understanding of the spatiotemporal coupling between transcriptional and post-transcriptional events in prokaryotes. We conclude by discussing future challenges of this multidisciplinary field.<b>Abbreviations:</b> mRNA: messenger RNA; rRNA: ribosomal rDNA; tRNA: transfer RNA; sRNA: small RNA; FISH: fluorescence <i>in situ</i> hybridization; RNP: ribonucleoprotein; smFISH: single RNA molecule FISH; smiFISH: single molecule inexpensive FISH; HCR-FISH: Hybridization Chain-Reaction-FISH; RCA: Rolling Circle Amplification; seqFISH: Sequential FISH; MERFISH: Multiplexed error robust FISH; UTR: Untranslated region; RBP: RNA binding protein; FP: fluorescent protein; eGFP: enhanced GFP, MCP: MS2 coat protein; PCP: PP7 coat protein; MB: Molecular beacons; sgRNA: single guide RNA.</p>","PeriodicalId":47009,"journal":{"name":"Transcription-Austin","volume":" ","pages":"105-126"},"PeriodicalIF":3.6,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10807504/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9778673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Transcription-AustinPub Date : 2023-06-01Epub Date: 2024-01-23DOI: 10.1080/21541264.2023.2295044
Sandra María Fernández-Moya, Akshay Jaya Ganesh, Mireya Plass
{"title":"Neural cell diversity in the light of single-cell transcriptomics.","authors":"Sandra María Fernández-Moya, Akshay Jaya Ganesh, Mireya Plass","doi":"10.1080/21541264.2023.2295044","DOIUrl":"10.1080/21541264.2023.2295044","url":null,"abstract":"<p><p>The development of highly parallel and affordable high-throughput single-cell transcriptomics technologies has revolutionized our understanding of brain complexity. These methods have been used to build cellular maps of the brain, its different regions, and catalog the diversity of cells in each of them during development, aging and even in disease. Now we know that cellular diversity is way beyond what was previously thought. Single-cell transcriptomics analyses have revealed that cell types previously considered homogeneous based on imaging techniques differ depending on several factors including sex, age and location within the brain. The expression profiles of these cells have also been exploited to understand which are the regulatory programs behind cellular diversity and decipher the transcriptional pathways driving them. In this review, we summarize how single-cell transcriptomics have changed our view on the cellular diversity in the human brain, and how it could impact the way we study neurodegenerative diseases. Moreover, we describe the new computational approaches that can be used to study cellular differentiation and gain insight into the functions of individual cell populations under different conditions and their alterations in disease.</p>","PeriodicalId":47009,"journal":{"name":"Transcription-Austin","volume":" ","pages":"158-176"},"PeriodicalIF":3.6,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10807474/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139479182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Transcription-AustinPub Date : 2023-06-01Epub Date: 2023-04-16DOI: 10.1080/21541264.2023.2200721
Pooja Sant, Karsten Rippe, Jan-Philipp Mallm
{"title":"Approaches for single-cell RNA sequencing across tissues and cell types.","authors":"Pooja Sant, Karsten Rippe, Jan-Philipp Mallm","doi":"10.1080/21541264.2023.2200721","DOIUrl":"10.1080/21541264.2023.2200721","url":null,"abstract":"<p><p>Single-cell sequencing of RNA (scRNA-seq) has advanced our understanding of cellular heterogeneity and signaling in developmental biology and disease. A large number of complementary assays have been developed to profile transcriptomes of individual cells, also in combination with other readouts, such as chromatin accessibility or antibody-based analysis of protein surface markers. As scRNA-seq technologies are advancing fast, it is challenging to establish robust workflows and up-to-date protocols that are best suited to address the large range of research questions. Here, we review scRNA-seq techniques from mRNA end-counting to total RNA in relation to their specific features and outline the necessary sample preparation steps and quality control measures. Based on our experience in dealing with the continuously growing portfolio from the perspective of a central single-cell facility, we aim to provide guidance on how workflows can be best automatized and share our experience in coping with the continuous expansion of scRNA-seq techniques.</p>","PeriodicalId":47009,"journal":{"name":"Transcription-Austin","volume":" ","pages":"127-145"},"PeriodicalIF":3.6,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10807473/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9761929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Transcription-AustinPub Date : 2023-06-01Epub Date: 2023-03-16DOI: 10.1080/21541264.2023.2190296
Rituparna Das, Anusree Dey, Sheetal Uppal
{"title":"A method for in situ visualization of Protein-Nascent RNA interactions in single cell using Proximity Ligation Assay (IPNR-PLA) in mammalian cells.","authors":"Rituparna Das, Anusree Dey, Sheetal Uppal","doi":"10.1080/21541264.2023.2190296","DOIUrl":"10.1080/21541264.2023.2190296","url":null,"abstract":"<p><p>Proximity ligation assay (PLA) is an immunofluorescence assay, which determines in situ interaction of two biomolecules present within 40 nm close proximity. Here, we describe a modification of PLA for visual detection of in situ protein interactions with nascent RNA in a single cell (IPNR-PLA). In IPNR-PLA, nascent RNA is labeled by incorporating 5-fluorouridine (FU), a uridine nucleotide analogue, followed by covalent cross-linking of the interacting partners in proximity to newly synthesized RNA. By using combination of anti-BrdU antibody, which specifically binds to FU, and primary antibody against a protein of interest, the IPNR reaction results in fluorescent puncta as a positive signal, only if the candidate proteins are in proximity to nascent RNA. We have validated this method by demonstrating known CDK9 and elongating RNA pol II interaction with nascent RNA. Finally, we used this method to test for the presence of DNA double strand breaks as well as Poly (ADP-ribose) polymerase 1 (PARP1), an RNA binding protein, in the vicinity of nascent RNA in cancer cells. The capability of performing parallel IF labeling and quantifiable multiparameter measurements within heterogeneous cell populations makes IPNR-PLA very attractive for use in biological studies. Overall, we have developed the IPNR-PLA method for analysis of protein association with nascent RNA with single-cell resolution, which is highly sensitive, quantitative, efficient, and requires little starting experimental material.</p>","PeriodicalId":47009,"journal":{"name":"Transcription-Austin","volume":" ","pages":"146-157"},"PeriodicalIF":3.6,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10807467/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9124822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Transcription-AustinPub Date : 2022-08-01Epub Date: 2022-09-25DOI: 10.1080/21541264.2022.2127602
Zachary F Mandell, Dani Zemba, Paul Babitzke
{"title":"Factor-stimulated intrinsic termination: getting by with a little help from some friends.","authors":"Zachary F Mandell, Dani Zemba, Paul Babitzke","doi":"10.1080/21541264.2022.2127602","DOIUrl":"10.1080/21541264.2022.2127602","url":null,"abstract":"<p><p>Transcription termination is known to occur via two mechanisms in bacteria, intrinsic termination (also frequently referred to as Rho-independent or factor-independent termination) and Rho-dependent termination. Based primarily on <i>in vitro</i> studies using <i>Escherichia coli</i> RNA polymerase, it was generally assumed that intrinsic termination and Rho-dependent termination are distinct mechanisms and that the signals required for intrinsic termination are present primarily within the nucleic acids. In this review, we detail recent findings from studies in <i>Bacillus subtilis</i> showing that intrinsic termination in this organism is highly stimulated by NusA, NusG, and even Rho. In NusA-stimulated intrinsic termination, NusA facilitates the formation of weak terminator hairpins and compensates for distal U-rich tract interruptions. In NusG-stimulated intrinsic termination, NusG stabilizes a sequence-dependent pause at the point of termination, which extends the time frame for RNA hairpins with weak terminal base pairs to form in either a NusA-stimulated or a NusA-independent fashion. In Rho-stimulated intrinsic termination, Rho prevents the formation of antiterminator-like RNA structures that could otherwise compete with the terminator hairpin. Combined, NusA, NusG, and Rho stimulate approximately 97% of all intrinsic terminators in <i>B. subtilis</i>. Thus, the general view that intrinsic termination is primarily a factor-independent process needs to be revised to account for recent findings. Moreover, the historical distinction between Rho-dependent and intrinsic termination is overly simplistic and needs to be modernized.</p>","PeriodicalId":47009,"journal":{"name":"Transcription-Austin","volume":"13 4-5","pages":"96-108"},"PeriodicalIF":3.6,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9715273/pdf/KTRN_13_2127602.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10516566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Alternative polyadenylation regulation: insights from sequential polyadenylation.","authors":"Peng Tang, Yu Zhou","doi":"10.1080/21541264.2022.2114776","DOIUrl":"https://doi.org/10.1080/21541264.2022.2114776","url":null,"abstract":"<p><p>The processing of the proximal and distal poly(A) sites in alternative polyadenylation (APA) has long been thought to independently occur on pre-mRNAs during transcription. However, a recent study by our groups demonstrated that the proximal sites for many genes could be activated sequentially following the distal ones, suggesting a multi-cleavage-same-transcript mode beyond the canonical one-cleavage-per-transcript view. Here, we review the established mechanisms for APA regulation and then discuss the additional insights into APA regulation from the perspective of sequential polyadenylation, resulting in a unified leverage model for understanding the mechanisms of regulated APA.</p>","PeriodicalId":47009,"journal":{"name":"Transcription-Austin","volume":"13 4-5","pages":"89-95"},"PeriodicalIF":3.6,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9715272/pdf/KTRN_13_2114776.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10063203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Function and dynamics of the Mediator complex: novel insights and new frontiers","authors":"R. Morse","doi":"10.1080/21541264.2022.2085502","DOIUrl":"https://doi.org/10.1080/21541264.2022.2085502","url":null,"abstract":"ABSTRACT The Mediator complex was discovered in the early 1990s as a biochemically fractionated factor from yeast extracts that was necessary for activator-stimulated transcriptional activation to be observed in in vitro transcription assays. The structure of this large, multi-protein complex is now understood in great detail, and novel genetic approaches have provided rich insights into its dynamics during transcriptional activation and the mechanism by which it facilitates activated transcription. Here I review recent findings and unanswered questions regarding Mediator dynamics, the roles of individual subunits, and differences between its function in yeast and metazoan cells.","PeriodicalId":47009,"journal":{"name":"Transcription-Austin","volume":"9 1","pages":"39 - 52"},"PeriodicalIF":3.6,"publicationDate":"2022-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80975616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A BEN-domain protein and polycomb complex work coordinately to regulate transcription.","authors":"Fredy Kurniawan, Supriya G Prasanth","doi":"10.1080/21541264.2022.2105128","DOIUrl":"https://doi.org/10.1080/21541264.2022.2105128","url":null,"abstract":"<p><p>Transcription regulation is an important mechanism that controls pluripotency and differentiation. Transcription factors dictate cell fate decisions by functioning cooperatively with chromatin regulators. We have recently demonstrated that BEND3 (BANP, E5R and Nac1 domain) protein regulates the expression of differentiation-associated genes by modulating the chromatin architecture at promoters. We highlight the collaboration of BEND3 with the polycomb repressive complex in coordinating transcription repression and propose a model highlighting the relevance of the BEND3-PRC2 axis in gene regulation and chromatin organization.<b>Abbreviations:</b> BEND3, BANP, E5R and Nac1 domain; rDNA, ribosomal DNA; PRC2, <i>Polycomb</i> Repressive Complex 2; H3K27me3, Histone H3 Lysine 27 methylation; PcG, Polycomb group.</p>","PeriodicalId":47009,"journal":{"name":"Transcription-Austin","volume":"13 1-3","pages":"82-87"},"PeriodicalIF":3.6,"publicationDate":"2022-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9467525/pdf/KTRN_13_2105128.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9888680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The histone chaperone FACT: a guardian of chromatin structure integrity.","authors":"Célia Jeronimo, François Robert","doi":"10.1080/21541264.2022.2069995","DOIUrl":"https://doi.org/10.1080/21541264.2022.2069995","url":null,"abstract":"<p><p>The identification of FACT as a histone chaperone enabling transcription through chromatin in vitro has strongly shaped how its roles are envisioned. However, FACT has been implicated in essentially all aspects of chromatin biology, from transcription to DNA replication, DNA repair, and chromosome segregation. In this review, we focus on recent literature describing the role and mechanisms of FACT during transcription. We highlight the prime importance of FACT in preserving chromatin integrity during transcription and challenge its role as an elongation factor. We also review evidence for FACT's role as a cell-type/gene-specific regulator of gene expression and briefly summarize current efforts at using FACT inhibition as an anti-cancer strategy.</p>","PeriodicalId":47009,"journal":{"name":"Transcription-Austin","volume":"13 1-3","pages":"16-38"},"PeriodicalIF":3.6,"publicationDate":"2022-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9467567/pdf/KTRN_13_2069995.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9360692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}