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Takallou S, Hajikarimlou M, Al-Gafari M, Wang J, Jagadeesan SK, Kazmirchuk TDD, Arnoczki C, Moteshareie H, Said KB, Azad T, Holcik M, Samanfar B, Smith M, Golshani A. Oxidative stress-induced YAP1 expression is regulated by NCE102, CDA2, and BCS1. FEBS J 2024. [PMID: 39102301 DOI: 10.1111/febs.17243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 05/31/2024] [Accepted: 07/24/2024] [Indexed: 08/07/2024]
Abstract
Maintaining cellular homeostasis in the face of stress conditions is vital for the overall well-being of an organism. Reactive oxygen species (ROS) are among the most potent cellular stressors and can disrupt the internal redox balance, giving rise to oxidative stress. Elevated levels of ROS can severely affect biomolecules and have been associated with a range of pathophysiological conditions. In response to oxidative stress, yeast activator protein-1 (Yap1p) undergoes post-translation modification that results in its nuclear accumulation. YAP1 has a key role in oxidative detoxification by promoting transcription of numerous antioxidant genes. In this study, we identified previously undescribed functions for NCE102, CDA2, and BCS1 in YAP1 expression in response to oxidative stress induced by hydrogen peroxide (H2O2). Deletion mutant strains for these candidates demonstrated increased sensitivity to H2O2. Our follow-up investigation linked the activity of these genes to YAP1 expression at the level of translation. Under oxidative stress, global cap-dependent translation is inhibited, prompting stress-responsive genes like YAP1 to employ alternative modes of translation. We provide evidence that NCE102, CDA2, and BCS1 contribute to cap-independent translation of YAP1 under oxidative stress.
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Affiliation(s)
- Sarah Takallou
- Ottawa Institute of Systems Biology, University of Ottawa, Canada
- Department of Biology, Carleton University, Ottawa, Canada
| | - Maryam Hajikarimlou
- Ottawa Institute of Systems Biology, University of Ottawa, Canada
- Department of Biology, Carleton University, Ottawa, Canada
| | - Mustafa Al-Gafari
- Ottawa Institute of Systems Biology, University of Ottawa, Canada
- Department of Biology, Carleton University, Ottawa, Canada
| | - Jiashu Wang
- Ottawa Institute of Systems Biology, University of Ottawa, Canada
- Department of Biology, Carleton University, Ottawa, Canada
| | - Sasi Kumar Jagadeesan
- Ottawa Institute of Systems Biology, University of Ottawa, Canada
- Department of Biology, Carleton University, Ottawa, Canada
| | - Thomas David Daniel Kazmirchuk
- Ottawa Institute of Systems Biology, University of Ottawa, Canada
- Department of Biology, Carleton University, Ottawa, Canada
| | | | - Houman Moteshareie
- Department of Biology, Carleton University, Ottawa, Canada
- Biotechnology Laboratory, Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Canada
| | - Kamaledin B Said
- Department of Pathology and Microbiology, College of Medicine, University of Hail, Saudi Arabia
| | - Taha Azad
- Department of Microbiology and Infectious Diseases, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Canada
- Research Center of the Centre Hospitalier Universitaire de Sherbrooke (CHUS), Canada
| | - Martin Holcik
- Department of Health Sciences, Carleton University, Ottawa, Canada
| | - Bahram Samanfar
- Ottawa Institute of Systems Biology, University of Ottawa, Canada
- Department of Biology, Carleton University, Ottawa, Canada
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre (ORDC), Canada
| | - Myron Smith
- Department of Biology, Carleton University, Ottawa, Canada
| | - Ashkan Golshani
- Ottawa Institute of Systems Biology, University of Ottawa, Canada
- Department of Biology, Carleton University, Ottawa, Canada
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2
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Zeng J, Song K, Wang J, Wen H, Zhou J, Ni T, Lu H, Yu Y. Characterization and optimization of 5´ untranslated region containing poly-adenine tracts in Kluyveromyces marxianus using machine-learning model. Microb Cell Fact 2024; 23:7. [PMID: 38172836 PMCID: PMC10763412 DOI: 10.1186/s12934-023-02271-3] [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] [Received: 10/15/2023] [Accepted: 12/12/2023] [Indexed: 01/05/2024] Open
Abstract
BACKGROUND The 5´ untranslated region (5´ UTR) plays a key role in regulating translation efficiency and mRNA stability, making it a favored target in genetic engineering and synthetic biology. A common feature found in the 5´ UTR is the poly-adenine (poly(A)) tract. However, the effect of 5´ UTR poly(A) on protein production remains controversial. Machine-learning models are powerful tools for explaining the complex contributions of features, but models incorporating features of 5´ UTR poly(A) are currently lacking. Thus, our goal is to construct such a model, using natural 5´ UTRs from Kluyveromyces marxianus, a promising cell factory for producing heterologous proteins. RESULTS We constructed a mini-library consisting of 207 5´ UTRs harboring poly(A) and 34 5´ UTRs without poly(A) from K. marxianus. The effects of each 5´ UTR on the production of a GFP reporter were evaluated individually in vivo, and the resulting protein abundance spanned an approximately 450-fold range throughout. The data were used to train a multi-layer perceptron neural network (MLP-NN) model that incorporated the length and position of poly(A) as features. The model exhibited good performance in predicting protein abundance (average R2 = 0.7290). The model suggests that the length of poly(A) is negatively correlated with protein production, whereas poly(A) located between 10 and 30 nt upstream of the start codon (AUG) exhibits a weak positive effect on protein abundance. Using the model as guidance, the deletion or reduction of poly(A) upstream of 30 nt preceding AUG tended to improve the production of GFP and a feruloyl esterase. Deletions of poly(A) showed inconsistent effects on mRNA levels, suggesting that poly(A) represses protein production either with or without reducing mRNA levels. CONCLUSION The effects of poly(A) on protein production depend on its length and position. Integrating poly(A) features into machine-learning models improves simulation accuracy. Deleting or reducing poly(A) upstream of 30 nt preceding AUG tends to enhance protein production. This optimization strategy can be applied to enhance the yield of K. marxianus and other microbial cell factories.
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Affiliation(s)
- Junyuan Zeng
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai, 200438, China
| | - Kunfeng Song
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai, 200438, China
| | - Jingqi Wang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai, 200438, China
| | - Haimei Wen
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai, 200438, China
| | - Jungang Zhou
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai, 200438, China
| | - Ting Ni
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai, 200438, China
| | - Hong Lu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai, 200438, China
| | - Yao Yu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China.
- Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai, 200438, China.
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3
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Reynaud K, McGeachy AM, Noble D, Meacham ZA, Ingolia NT. Surveying the global landscape of post-transcriptional regulators. Nat Struct Mol Biol 2023; 30:740-752. [PMID: 37231154 PMCID: PMC10279529 DOI: 10.1038/s41594-023-00999-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 04/17/2023] [Indexed: 05/27/2023]
Abstract
Numerous proteins regulate gene expression by modulating mRNA translation and decay. To uncover the full scope of these post-transcriptional regulators, we conducted an unbiased survey that quantifies regulatory activity across the budding yeast proteome and delineates the protein domains responsible for these effects. Our approach couples a tethered function assay with quantitative single-cell fluorescence measurements to analyze ~50,000 protein fragments and determine their effects on a tethered mRNA. We characterize hundreds of strong regulators, which are enriched for canonical and unconventional mRNA-binding proteins. Regulatory activity typically maps outside the RNA-binding domains themselves, highlighting a modular architecture that separates mRNA targeting from post-transcriptional regulation. Activity often aligns with intrinsically disordered regions that can interact with other proteins, even in core mRNA translation and degradation factors. Our results thus reveal networks of interacting proteins that control mRNA fate and illuminate the molecular basis for post-transcriptional gene regulation.
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Affiliation(s)
- Kendra Reynaud
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA, USA
| | - Anna M McGeachy
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
| | - David Noble
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Zuriah A Meacham
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Nicholas T Ingolia
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA, USA.
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA.
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4
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Chowdhury MN, Chen X, Jin H. An intrinsically Disordered RNA Binding Protein Modulates mRNA Translation and Storage. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.22.541713. [PMID: 37293096 PMCID: PMC10245857 DOI: 10.1101/2023.05.22.541713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Many proteins with intrinsically disordered regions interact with cytoplasmic ribosomes. However, many of the molecular functions related to these interactions are unclear. In this study, using an abundant RNA-binding protein with a structurally well-defined RNA recognition motif and an intrinsically disordered RGG domain as a model system, we investigated how this protein modulates mRNA storage and translation. Using genomic and molecular approaches, we show that the presence of Sbp1 slows ribosome movement on cellular mRNAs and promotes polysome stalling. Sbp1-associated polysomes display a ring-shaped structure in addition to a beads-on-string morphology visualized under electron microscope. Moreover, post-translational modifications at the RGG motif play important roles in directing cellular mRNAs to either translation or storage. Finally, binding of Sbp1 to the 5'UTRs of mRNAs represses both cap-dependent and cap-independent translation initiation of proteins functionally important for general protein synthesis in the cell. Taken together, our study demonstrates an intrinsically disordered RNA binding protein regulates mRNA translation and storage via distinctive mechanisms under physiological conditions and establishes a framework with which functions of important RGG-proteins can be investigated and defined.
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Affiliation(s)
- Mashiat N. Chowdhury
- Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, IL 61801
| | - Xin Chen
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, IL 61801
| | - Hong Jin
- Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, IL 61801
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, IL 61801
- Carl R. Woese Institute for Genomic Biology, 1206 West Gregory Drive, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, IL 61801
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5
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Balzarini S, Van Ende R, Voet A, Geuten K. A widely applicable and cost-effective method for specific RNA-protein complex isolation. Sci Rep 2023; 13:6898. [PMID: 37106019 PMCID: PMC10140378 DOI: 10.1038/s41598-023-34157-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 04/24/2023] [Indexed: 04/29/2023] Open
Abstract
Although methodological advances have been made over the past years, a widely applicable, easily scalable and cost-effective procedure that can be routinely used to isolate specific ribonucleoprotein complexes (RNPs) remains elusive. We describe the "Silica-based Acidic Phase Separation (SAPS)-capture" workflow. This versatile method combines previously described techniques in a cost-effective, optimal and widely applicable protocol. The specific RNP isolation procedure is performed on a pre-purified RNP sample instead of cell lysate. This combination of protocols results in an increased RNP/bead ratio and by consequence a reduced experimental cost. To validate the method, the 18S rRNP of S. cerevisiae was captured and to illustrate its applicability we isolated the complete repertoire of RNPs in A. thaliana. The procedure we describe can provide the community with a powerful tool to advance the study of the ribonome of a specific RNA molecule in any organism or tissue type.
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Affiliation(s)
- Sam Balzarini
- Molecular Biotechnology of Plants and Micro-organisms, KU Leuven, 3001, Leuven, Belgium
| | - Roosje Van Ende
- Molecular Biotechnology of Plants and Micro-organisms, KU Leuven, 3001, Leuven, Belgium
| | - Arnout Voet
- Lab of biomolecular modelling and design, KU Leuven, 3001, Leuven, Belgium
| | - Koen Geuten
- Molecular Biotechnology of Plants and Micro-organisms, KU Leuven, 3001, Leuven, Belgium.
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6
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Chowdhury MN, Jin H. The RGG motif proteins: Interactions, functions, and regulations. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1748. [PMID: 35661420 PMCID: PMC9718894 DOI: 10.1002/wrna.1748] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 04/25/2022] [Accepted: 05/09/2022] [Indexed: 01/31/2023]
Abstract
Proteins with motifs rich in arginines and glycines were discovered decades ago and are functionally involved in a staggering range of essential processes in the cell. Versatile, specific, yet adaptable molecular interactions enabled by the unique combination of arginine and glycine, combined with multiplicity of molecular recognition conferred by repeated di-, tri-, and multiple peptide motifs, allow RGG motif proteins to interact with a broad range of proteins and nucleic acids. Furthermore, posttranslational modifications at the arginines in the motif extend the RGG protein's capacity for a fine-tuned regulation. In this review, we focus on the biochemical properties of the RGG motif, its molecular interactions with RNAs and proteins, and roles of the posttranslational modification in modulating their interactions. We discuss current knowledge of the RGG motif proteins involved in mRNA transport and translation, highlight our merging understanding of their molecular functions in translational regulation and summarize areas of research in the future critical in understanding this important family of proteins. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Recognition RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications Translation > Mechanisms.
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Affiliation(s)
- Mashiat N. Chowdhury
- Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, IL 61801
| | - Hong Jin
- Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, IL 61801,Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, IL 61801,Carl R. Woese Institute for Genomic Biology, 1206 West Gregory Drive, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, IL 61801,Corresponding author: Phone: (217)244-9493, Fax: (217)244-5858,
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7
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Roy R, Rajyaguru PI. Assay to Study the Phase-transition Behavior of Edc3, a Conserved Processing Body (P-body) Marker Protein. Bio Protoc 2022; 12:e4487. [PMID: 36199703 PMCID: PMC9486690 DOI: 10.21769/bioprotoc.4487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 07/03/2022] [Accepted: 07/04/2022] [Indexed: 12/29/2022] Open
Abstract
RNA granules are conserved, non-membranous, biphasic structures predominantly composed of RNA and RNA-binding proteins. RNA granules often assemble as a result of cellular responses to a variety of stresses, including infection. Two types of RNA granules are best characterized: stress granules (SGs) and processing bodies (P-bodies). The mechanism of RNA granule assembly and disassembly is still understudied because of its complex composition and dynamic behavior. The assembly of RNA granules is driven by a process known as phase separation of granule components. Edc3 is a conserved decapping activator and an essential P-body component in Saccharomyces cerevisiae. Phase separation of P-body proteins has been poorly explored. This protocol will enable the visualization of the phase transition behavior of Edc3, since it is tagged to mCherry. It further describes using small molecules and other proteins to study P-body dynamics. In addition to the assembly of Edc3, this assay also lays the foundation to study disassembly of phase-separated assemblies in vitro , which was not explored earlier. We have devised the assay to describe the use of one such protein that acts as a disassembly factor. Overall, this protocol is simple to perform and can potentially be combined with analyzing these assemblies using other approaches. Graphical abstract.
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Affiliation(s)
- Raju Roy
- Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India
| | - Purusharth I. Rajyaguru
- Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India
,
*For correspondence:
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8
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Roy R, Das G, Kuttanda IA, Bhatter N, Rajyaguru PI. Low complexity RGG-motif sequence is required for Processing body (P-body) disassembly. Nat Commun 2022; 13:2077. [PMID: 35440550 PMCID: PMC9019020 DOI: 10.1038/s41467-022-29715-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 03/21/2022] [Indexed: 01/12/2023] Open
Abstract
P-bodies are conserved mRNP complexes that are implicated in determining mRNA fate by affecting translation and mRNA decay. In this report, we identify RGG-motif containing translation repressor protein Sbp1 as a disassembly factor of P-bodies since disassembly of P-bodies is defective in Δsbp1. RGG-motif is necessary and sufficient to rescue the PB disassembly defect in Δsbp1. Binding studies using purified proteins revealed that Sbp1 physically interacts with Edc3 and Sbp1-Edc3 interaction competes with Edc3-Edc3 interaction. Purified Edc3 forms assemblies, promoted by the presence of RNA and NADH and the addition of purified Sbp1, but not the RGG-deletion mutant, leads to significantly decreased Edc3 assemblies. We further note that the aggregates of human EWSR1 protein, implicated in neurodegeneration, are more persistent in the absence of Sbp1 and overexpression of EWSR1 in Δsbp1 leads to a growth defect. Taken together, our observations suggest a role of Sbp1 in disassembly, which could apply to disease-relevant heterologous protein-aggregates.
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Affiliation(s)
- Raju Roy
- Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India
| | - Gitartha Das
- Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India
| | | | - Nupur Bhatter
- Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India
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9
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Parbin S, Damodharan S, Rajyaguru PI. Arginine methylation and cytoplasmic mRNA fate: An exciting new partnership. Yeast 2021; 38:441-452. [PMID: 34048611 DOI: 10.1002/yea.3653] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 05/12/2021] [Accepted: 05/20/2021] [Indexed: 12/22/2022] Open
Abstract
Posttranslational modifications play a crucial role in regulating gene expression. Among these modifications, arginine methylation has recently attracted tremendous attention due to its role in multiple cellular functions. This review discusses the recent advances that have established arginine methylation as a major player in determining cytoplasmic messenger RNA (mRNA) fate. We specifically focus on research that implicates arginine methylation in regulating mRNA translation, decay, and RNA granule dynamics. Based on this research, we highlight a few emerging future avenues that will lead to exciting discoveries in this field.
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Affiliation(s)
- Sabnam Parbin
- Department of Biochemistry, Indian Institute of Science, Bangalore, India.,Integrative Genomics Core Unit, University Medical Centre, Göttingen, Göttingen, Germany
| | - Subha Damodharan
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
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10
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Yin Z, Liu X, Ariosa A, Huang H, Jin M, Karbstein K, Klionsky DJ. Psp2, a novel regulator of autophagy that promotes autophagy-related protein translation. Cell Res 2019; 29:994-1008. [PMID: 31666677 DOI: 10.1038/s41422-019-0246-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 09/05/2019] [Indexed: 01/27/2023] Open
Abstract
Macroautophagy/autophagy defines an evolutionarily conserved catabolic process that targets cytoplasmic components for lysosomal degradation. The process of autophagy from initiation to closure is tightly executed and controlled by the concerted action of autophagy-related (Atg) proteins. Although substantial progress has been made in characterizing transcriptional and post-translational regulation of ATG/Atg genes/proteins, little is known about the translational control of autophagy. Here we report that Psp2, an RGG motif protein, positively regulates autophagy through promoting the translation of Atg1 and Atg13, two proteins that are crucial in the initiation of autophagy. During nitrogen starvation conditions, Psp2 interacts with the 5' UTR of ATG1 and ATG13 transcripts in an RGG motif-dependent manner and with eIF4E and eIF4G2, components of the translation initiation machinery, to regulate the translation of these transcripts. Deletion of the PSP2 gene leads to a decrease in the synthesis of Atg1 and Atg13, which correlates with reduced autophagy activity and cell survival. Furthermore, deactivation of the methyltransferase Hmt1 constitutes a molecular switch that regulates Psp2 arginine methylation status as well as its mRNA binding activity in response to starvation. These results reveal a novel mechanism by which Atg proteins become upregulated to fulfill the increased demands of autophagy activity as part of translational reprogramming during stress conditions, and help explain how ATG genes bypass the general block in protein translation that occurs during starvation.
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Affiliation(s)
- Zhangyuan Yin
- Life Sciences Institute, and the Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Xu Liu
- Life Sciences Institute, and the Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA.,Harvard Medical School, Department of Microbiology, Brigham and Women's Hospital, Division of Infectious Diseases, Boston, MA, USA
| | - Aileen Ariosa
- Life Sciences Institute, and the Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Haina Huang
- The Scripps Research Institute, Department of Integrative Structural and Computational Biology, Jupiter, FL, 33458, USA
| | - Meiyan Jin
- Life Sciences Institute, and the Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA.,Department of Molecular and Cell Biology, University of California, Berkeley, CA, 94720, USA
| | - Katrin Karbstein
- The Scripps Research Institute, Department of Integrative Structural and Computational Biology, Jupiter, FL, 33458, USA
| | - Daniel J Klionsky
- Life Sciences Institute, and the Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA.
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11
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You ST, Jhou YT, Kao CF, Leu JY. Experimental evolution reveals a general role for the methyltransferase Hmt1 in noise buffering. PLoS Biol 2019; 17:e3000433. [PMID: 31613873 PMCID: PMC6814240 DOI: 10.1371/journal.pbio.3000433] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 10/25/2019] [Accepted: 09/27/2019] [Indexed: 11/19/2022] Open
Abstract
Cell-to-cell heterogeneity within an isogenic population has been observed in prokaryotic and eukaryotic cells. Such heterogeneity often manifests at the level of individual protein abundance and may have evolutionary benefits, especially for organisms in fluctuating environments. Although general features and the origins of cellular noise have been revealed, details of the molecular pathways underlying noise regulation remain elusive. Here, we used experimental evolution of Saccharomyces cerevisiae to select for mutations that increase reporter protein noise. By combining bulk segregant analysis and CRISPR/Cas9-based reconstitution, we identified the methyltransferase Hmt1 as a general regulator of noise buffering. Hmt1 methylation activity is critical for the evolved phenotype, and we also show that two of the Hmt1 methylation targets can suppress noise. Hmt1 functions as an environmental sensor to adjust noise levels in response to environmental cues. Moreover, Hmt1-mediated noise buffering is conserved in an evolutionarily distant yeast species, suggesting broad significance of noise regulation. Experimental evolution in yeast reveals that the methyltransferase Hmt1 functions as a mediator connecting environmental stimuli to cellular noise; Hmt1-mediated noise buffering is conserved in an evolutionarily distant yeast.
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Affiliation(s)
- Shu-Ting You
- Molecular and Cell Biology, Taiwan International Graduate Program, Graduate Institute of Life Sciences, National Defense Medical Center and Academia Sinica, Taipei, Taiwan
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Yu-Ting Jhou
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Cheng-Fu Kao
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Jun-Yi Leu
- Molecular and Cell Biology, Taiwan International Graduate Program, Graduate Institute of Life Sciences, National Defense Medical Center and Academia Sinica, Taipei, Taiwan
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
- * E-mail:
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12
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Bhatter N, Roy R, Shah S, Sastry SP, Parbin S, Iyappan R, Kankaria S, Rajyaguru PI. Arginine methylation augments Sbp1 function in translation repression and decapping. FEBS J 2019; 286:4693-4708. [PMID: 31495062 PMCID: PMC6916386 DOI: 10.1111/febs.15057] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 06/29/2019] [Accepted: 09/03/2019] [Indexed: 12/16/2022]
Abstract
The fate of messenger RNA in cytoplasm plays a crucial role in various cellular processes. However, the mechanisms that decide whether mRNA will be translated, degraded or stored remain unclear. Single stranded nucleic acid binding protein (Sbp1), an Arginine‐Glycine‐Glycine (RGG‐motif) protein, is known to promote transition of mRNA into a repressed state by binding eukaryotic translation initiation factor 4G1 (eIF4G1) and to promote mRNA decapping, perhaps by modulation of Dcp1/2 activity. Sbp1 is known to be methylated on arginine residues in RGG‐motif; however, the functional relevance of this modification in vivo remains unknown. Here, we report that Sbp1 is arginine‐methylated in an hnRNP methyl transferase (Hmt1)‐dependent manner and that methylation is enhanced upon glucose deprivation. Characterization of an arginine‐methylation‐defective (AMD) mutant provided evidence that methylation affects Sbp1 function in vivo. The AMD mutant is compromised in causing growth defect upon overexpression, and the mutant is defective in both localizing to and inducing granule formation. Importantly, the Sbp1‐eIF4G1 interaction is compromised both for the AMD mutant and in the absence of Hmt1. Upon overexpression, wild‐type Sbp1 increases localization of another RGG motif containing protein, Scd6 (suppressor of clathrin deficiency) to granules; however, this property of Sbp1 is compromised in the AMD mutant and in the absence of Hmt1, indicating that Sbp1 repression activity could involve other RGG‐motif translation repressors. Additionally, the AMD mutant fails to increase localization of the decapping activator DEAD box helicase homolog to foci and fails to rescue the decapping defect of a dcp1‐2Δski8 strain, highlighting the role of Sbp1 methylation in decapping. Taken together, these results suggest that arginine methylation modulates Sbp1 role in mRNA fate determination.
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Affiliation(s)
- Nupur Bhatter
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Raju Roy
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | | | - Sneha P Sastry
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Sabnam Parbin
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | | | - Siddharth Kankaria
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
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13
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Roy D, Rajyaguru PI. Suppressor of clathrin deficiency (Scd6)-An emerging RGG-motif translation repressor. WILEY INTERDISCIPLINARY REVIEWS-RNA 2018; 9:e1479. [DOI: 10.1002/wrna.1479] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 03/07/2018] [Accepted: 03/07/2018] [Indexed: 12/15/2022]
Affiliation(s)
- Debadrita Roy
- Department of Biochemistry; Indian Institute of Science; Bangalore India
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