1
|
Burgardt R, Lambert D, Heuwieser C, Sack M, Wagner G, Weinberg Z, Wachter A. Positioning of pyrimidine motifs around cassette exons defines their PTB-dependent splicing in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:2202-2218. [PMID: 38578875 DOI: 10.1111/tpj.16739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Accepted: 03/14/2024] [Indexed: 04/07/2024]
Abstract
Alternative splicing (AS) is a complex process that generates transcript variants from a single pre-mRNA and is involved in numerous biological functions. Many RNA-binding proteins are known to regulate AS; however, little is known about the underlying mechanisms, especially outside the mammalian clade. Here, we show that polypyrimidine tract binding proteins (PTBs) from Arabidopsis thaliana regulate AS of cassette exons via pyrimidine (Py)-rich motifs close to the alternative splice sites. Mutational studies on three PTB-dependent cassette exon events revealed that only some of the Py motifs in this region are critical for AS. Moreover, in vitro binding of PTBs did not reflect a motif's impact on AS in vivo. Our mutational studies and bioinformatic investigation of all known PTB-regulated cassette exons from A. thaliana and human suggested that the binding position of PTBs relative to a cassette exon defines whether its inclusion or skipping is induced. Accordingly, exon skipping is associated with a higher frequency of Py stretches within the cassette exon, and in human also upstream of it, whereas exon inclusion is characterized by increased Py motif occurrence downstream of said exon. Enrichment of Py motifs downstream of PTB-activated 5' splice sites is also seen for PTB-dependent intron removal and alternative 5' splice site events from A. thaliana, suggesting this is a common step of exon definition. In conclusion, the position-dependent AS regulatory mechanism by PTB homologs has been conserved during the separate evolution of plants and mammals, while other critical features, in particular intron length, have considerably changed.
Collapse
Affiliation(s)
- Rica Burgardt
- Institute for Molecular Physiology (imP), University of Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128, Mainz, Germany
| | - Dorothee Lambert
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Christina Heuwieser
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Maximilian Sack
- Bioinformatics Group, Department of Computer Science and Interdisciplinary Centre for Bioinformatics, Leipzig University, Härtelstraße 16-18, 04107, Leipzig, Germany
| | - Gabriele Wagner
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Zasha Weinberg
- Bioinformatics Group, Department of Computer Science and Interdisciplinary Centre for Bioinformatics, Leipzig University, Härtelstraße 16-18, 04107, Leipzig, Germany
| | - Andreas Wachter
- Institute for Molecular Physiology (imP), University of Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128, Mainz, Germany
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| |
Collapse
|
2
|
Chen G, Chen J, Qi L, Yin Y, Lin Z, Wen H, Zhang S, Xiao C, Bello SF, Zhang X, Nie Q, Luo W. Bulk and single-cell alternative splicing analyses reveal roles of TRA2B in myogenic differentiation. Cell Prolif 2024; 57:e13545. [PMID: 37705195 PMCID: PMC10849790 DOI: 10.1111/cpr.13545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 08/08/2023] [Accepted: 08/28/2023] [Indexed: 09/15/2023] Open
Abstract
Alternative splicing (AS) disruption has been linked to disorders of muscle development, as well as muscular atrophy. However, the precise changes in AS patterns that occur during myogenesis are not well understood. Here, we employed isoform long-reads RNA-seq (Iso-seq) and single-cell RNA-seq (scRNA-seq) to investigate the AS landscape during myogenesis. Our Iso-seq data identified 61,146 full-length isoforms representing 11,682 expressed genes, of which over 52% were novel. We identified 38,022 AS events, with most of these events altering coding sequences and exhibiting stage-specific splicing patterns. We identified AS dynamics in different types of muscle cells through scRNA-seq analysis, revealing genes essential for the contractile muscle system and cytoskeleton that undergo differential splicing across cell types. Gene-splicing analysis demonstrated that AS acts as a regulator, independent of changes in overall gene expression. Two isoforms of splicing factor TRA2B play distinct roles in myogenic differentiation by triggering AS of TGFBR2 to regulate canonical TGF-β signalling cascades differently. Our study provides a valuable transcriptome resource for myogenesis and reveals the complexity of AS and its regulation during myogenesis.
Collapse
Affiliation(s)
- Genghua Chen
- College of Animal ScienceSouth China Agricultural UniversityGuangzhouGuangdongChina
- Guangdong Provincial Key Lab of Agro‐Animal Genomics and Molecular Breeding, Lingnan Guangdong Laboratory of Modern Agriculture & State Key Laboratory for Conservation and Utilization of Subtropical Agro‐Bioresources, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of AgricultureGuangzhouGuangdongChina
- State Key Laboratory of Livestock and Poultry Breeding, and Lingnan Guangdong Laboratory of AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Jiahui Chen
- College of Animal ScienceSouth China Agricultural UniversityGuangzhouGuangdongChina
- Guangdong Provincial Key Lab of Agro‐Animal Genomics and Molecular Breeding, Lingnan Guangdong Laboratory of Modern Agriculture & State Key Laboratory for Conservation and Utilization of Subtropical Agro‐Bioresources, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of AgricultureGuangzhouGuangdongChina
- State Key Laboratory of Livestock and Poultry Breeding, and Lingnan Guangdong Laboratory of AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Lin Qi
- College of Animal ScienceSouth China Agricultural UniversityGuangzhouGuangdongChina
- Guangdong Provincial Key Lab of Agro‐Animal Genomics and Molecular Breeding, Lingnan Guangdong Laboratory of Modern Agriculture & State Key Laboratory for Conservation and Utilization of Subtropical Agro‐Bioresources, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of AgricultureGuangzhouGuangdongChina
- State Key Laboratory of Livestock and Poultry Breeding, and Lingnan Guangdong Laboratory of AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Yunqian Yin
- College of Animal ScienceSouth China Agricultural UniversityGuangzhouGuangdongChina
- Guangdong Provincial Key Lab of Agro‐Animal Genomics and Molecular Breeding, Lingnan Guangdong Laboratory of Modern Agriculture & State Key Laboratory for Conservation and Utilization of Subtropical Agro‐Bioresources, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of AgricultureGuangzhouGuangdongChina
- State Key Laboratory of Livestock and Poultry Breeding, and Lingnan Guangdong Laboratory of AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Zetong Lin
- College of Animal ScienceSouth China Agricultural UniversityGuangzhouGuangdongChina
- Guangdong Provincial Key Lab of Agro‐Animal Genomics and Molecular Breeding, Lingnan Guangdong Laboratory of Modern Agriculture & State Key Laboratory for Conservation and Utilization of Subtropical Agro‐Bioresources, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of AgricultureGuangzhouGuangdongChina
- State Key Laboratory of Livestock and Poultry Breeding, and Lingnan Guangdong Laboratory of AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Huaqiang Wen
- College of Animal ScienceSouth China Agricultural UniversityGuangzhouGuangdongChina
- Guangdong Provincial Key Lab of Agro‐Animal Genomics and Molecular Breeding, Lingnan Guangdong Laboratory of Modern Agriculture & State Key Laboratory for Conservation and Utilization of Subtropical Agro‐Bioresources, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of AgricultureGuangzhouGuangdongChina
- State Key Laboratory of Livestock and Poultry Breeding, and Lingnan Guangdong Laboratory of AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Shuai Zhang
- College of Animal ScienceSouth China Agricultural UniversityGuangzhouGuangdongChina
- Guangdong Provincial Key Lab of Agro‐Animal Genomics and Molecular Breeding, Lingnan Guangdong Laboratory of Modern Agriculture & State Key Laboratory for Conservation and Utilization of Subtropical Agro‐Bioresources, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of AgricultureGuangzhouGuangdongChina
- State Key Laboratory of Livestock and Poultry Breeding, and Lingnan Guangdong Laboratory of AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Chuanyun Xiao
- Human and Animal PhysiologyWageningen UniversityWageningenThe Netherlands
| | - Semiu Folaniyi Bello
- College of Animal ScienceSouth China Agricultural UniversityGuangzhouGuangdongChina
- Guangdong Provincial Key Lab of Agro‐Animal Genomics and Molecular Breeding, Lingnan Guangdong Laboratory of Modern Agriculture & State Key Laboratory for Conservation and Utilization of Subtropical Agro‐Bioresources, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of AgricultureGuangzhouGuangdongChina
- State Key Laboratory of Livestock and Poultry Breeding, and Lingnan Guangdong Laboratory of AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Xiquan Zhang
- College of Animal ScienceSouth China Agricultural UniversityGuangzhouGuangdongChina
- Guangdong Provincial Key Lab of Agro‐Animal Genomics and Molecular Breeding, Lingnan Guangdong Laboratory of Modern Agriculture & State Key Laboratory for Conservation and Utilization of Subtropical Agro‐Bioresources, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of AgricultureGuangzhouGuangdongChina
- State Key Laboratory of Livestock and Poultry Breeding, and Lingnan Guangdong Laboratory of AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Qinghua Nie
- College of Animal ScienceSouth China Agricultural UniversityGuangzhouGuangdongChina
- Guangdong Provincial Key Lab of Agro‐Animal Genomics and Molecular Breeding, Lingnan Guangdong Laboratory of Modern Agriculture & State Key Laboratory for Conservation and Utilization of Subtropical Agro‐Bioresources, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of AgricultureGuangzhouGuangdongChina
- State Key Laboratory of Livestock and Poultry Breeding, and Lingnan Guangdong Laboratory of AgricultureSouth China Agricultural UniversityGuangzhouChina
| | - Wen Luo
- College of Animal ScienceSouth China Agricultural UniversityGuangzhouGuangdongChina
- Guangdong Provincial Key Lab of Agro‐Animal Genomics and Molecular Breeding, Lingnan Guangdong Laboratory of Modern Agriculture & State Key Laboratory for Conservation and Utilization of Subtropical Agro‐Bioresources, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of AgricultureGuangzhouGuangdongChina
- State Key Laboratory of Livestock and Poultry Breeding, and Lingnan Guangdong Laboratory of AgricultureSouth China Agricultural UniversityGuangzhouChina
| |
Collapse
|
3
|
Wester LE, Lanjuin A, Bruckisch EH, Perez-Matos MC, Stine PG, Heintz C, Denzel MS, Mair WB. A single-copy knockin translating ribosome immunoprecipitation toolkit for tissue-specific profiling of actively translated mRNAs in C. elegans. CELL REPORTS METHODS 2023; 3:100433. [PMID: 37056370 PMCID: PMC10088236 DOI: 10.1016/j.crmeth.2023.100433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 01/11/2023] [Accepted: 02/28/2023] [Indexed: 03/29/2023]
Abstract
Here, we introduce a single-copy knockin translating ribosome immunoprecipitation (SKI TRIP) toolkit, a collection of Caenorhabditis elegans strains engineered by CRISPR in which tissue-specific expression of FLAG-tagged ribosomal subunit protein RPL-22 is driven by cassettes present in single copy from defined sites in the genome. Through in-depth characterization of the effects of the FLAG tag in animals in which endogenous RPL-22 has been tagged, we show that it incorporates into actively translating ribosomes and efficiently and cleanly pulls down cell-type-specific transcripts. Importantly, the presence of the tag does not impact overall mRNA translation, create bias in transcript use, or cause changes to fitness of the animal. We propose SKI TRIP use for the study of tissue-specific differences in translation and for investigating processes that are acutely sensitive to changes in translation like development or aging.
Collapse
Affiliation(s)
- Laura E. Wester
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
- Department of Molecular Genetics of Ageing, Max Planck Institute for Biology of Ageing, 50668 Cologne, Germany
| | - Anne Lanjuin
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Emanuel H.W. Bruckisch
- Department of Molecular Genetics of Ageing, Max Planck Institute for Biology of Ageing, 50668 Cologne, Germany
| | - Maria C. Perez-Matos
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Peter G. Stine
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Caroline Heintz
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Martin S. Denzel
- Department of Molecular Genetics of Ageing, Max Planck Institute for Biology of Ageing, 50668 Cologne, Germany
- Altos Labs, Cambridge, UK
| | - William B. Mair
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| |
Collapse
|
4
|
Calarco JA, Pilaka-Akella PP. Two-Color Fluorescent Reporters for Analysis of Alternative Splicing. Methods Mol Biol 2022; 2537:211-229. [PMID: 35895267 DOI: 10.1007/978-1-0716-2521-7_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Alternative splicing is a key layer of gene regulation that is frequently modulated in a spatiotemporal manner. As such, it is a major goal to understand the mechanisms controlling alternative splicing in specific cellular contexts. Reporters that recapitulate alternative splicing patterns of endogenous transcripts have served as excellent tools for dissecting regulatory mechanisms of splicing. In this chapter, we describe a two-color fluorescent reporter system that enables the visualization of alternative splicing patterns by microscopy at single-cell resolution in live animals. We present this reporter system in the context of the model nematode C. elegans.
Collapse
Affiliation(s)
- John A Calarco
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada.
| | | |
Collapse
|
5
|
Choudhary B, Marx O, Norris AD. Spliceosomal component PRP-40 is a central regulator of microexon splicing. Cell Rep 2021; 36:109464. [PMID: 34348142 PMCID: PMC8378409 DOI: 10.1016/j.celrep.2021.109464] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 05/31/2021] [Accepted: 07/08/2021] [Indexed: 02/07/2023] Open
Abstract
Microexons (≤27 nt) play critical roles in nervous system development and function but create unique challenges for the splicing machinery. The mechanisms of microexon regulation are therefore of great interest. We performed a genetic screen for alternative splicing regulators in the C. elegans nervous system and identify PRP-40, a core component of the U1 snRNP. RNA-seq reveals that PRP-40 is required for inclusion of alternatively spliced, but not constitutively spliced, exons. PRP-40 is particularly required for inclusion of neuronal microexons, and our data indicate that PRP-40 is a central regulator of microexon splicing. Microexons can be relieved from PRP-40 dependence by artificially increasing exon size or reducing flanking intron size, indicating that PRP-40 is specifically required for microexons surrounded by conventionally sized introns. Knockdown of the orthologous PRPF40A in mouse neuroblastoma cells causes widespread dysregulation of microexons but not conventionally sized exons. PRP-40 regulation of neuronal microexons is therefore a widely conserved phenomenon.
Collapse
Affiliation(s)
- Bikash Choudhary
- Biological Sciences, Southern Methodist University, Dallas, TX 75275, USA
| | - Olivia Marx
- Biological Sciences, Southern Methodist University, Dallas, TX 75275, USA
| | - Adam D Norris
- Biological Sciences, Southern Methodist University, Dallas, TX 75275, USA.
| |
Collapse
|
6
|
Byrd DT, Jin Y. Wired for insight-recent advances in Caenorhabditis elegans neural circuits. Curr Opin Neurobiol 2021; 69:159-169. [PMID: 33957432 PMCID: PMC8387325 DOI: 10.1016/j.conb.2021.02.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/16/2021] [Accepted: 02/22/2021] [Indexed: 11/15/2022]
Abstract
The completion of Caenorhabditis elegans connectomics four decades ago has long guided mechanistic investigation of neuronal circuits. Recent technological advances in microscopy and computation programs have aided re-examination of this connectomics, expanding our knowledge by both uncovering previously unreported synaptic connections and also generating models for neural networks underlying behaviors. Combining molecular information from single cell transcriptomes with elegant tools for cell-specific manipulation has further enhanced the ability to precisely investigate individual neurons in behaving animals. This mini-review aims to provide an overview of new information on connectomics and progress toward a molecular atlas of C. elegans nervous system, and discuss emerging findings on neuronal circuits.
Collapse
Affiliation(s)
- Dana T Byrd
- Neurobiology Section, University of California San Diego, La Jolla, CA, 92093, USA.
| | - Yishi Jin
- Neurobiology Section, University of California San Diego, La Jolla, CA, 92093, USA; Kavli Institute of Brain and Mind, University of California San Diego, La Jolla, CA, 92093, USA.
| |
Collapse
|