1
|
Baer MH, Cascarina SM, Paul KR, Ross ED. Rational Tuning of the Concentration-independent Enrichment of Prion-like Domains in Stress Granules. J Mol Biol 2024; 436:168703. [PMID: 39004265 DOI: 10.1016/j.jmb.2024.168703] [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: 05/06/2024] [Revised: 06/27/2024] [Accepted: 07/09/2024] [Indexed: 07/16/2024]
Abstract
Stress granules (SGs) are large ribonucleoprotein assemblies that form in response to acute stress in eukaryotes. SG formation is thought to be initiated by liquid-liquid phase separation (LLPS) of key proteins and RNA. These molecules serve as a scaffold for recruitment of client molecules. LLPS of scaffold proteins in vitro is highly concentration-dependent, yet biomolecular condensates in vivo contain hundreds of unique proteins, most of which are thought to be clients rather than scaffolds. Many proteins that localize to SGs contain low-complexity, prion-like domains (PrLDs) that have been implicated in LLPS and SG recruitment. The degree of enrichment of proteins in biomolecular condensates such as SGs can vary widely, but the underlying basis for these differences is not fully understood. Here, we develop a toolkit of model PrLDs to examine the factors that govern efficiency of PrLD recruitment to stress granules. Recruitment was highly sensitive to amino acid composition: enrichment in SGs could be tuned through subtle changes in hydrophobicity. By contrast, SG recruitment was largely insensitive to PrLD concentration at both a population level and single-cell level. These observations point to a model wherein PrLDs are enriched in SGs through either simple solvation effects or interactions that are effectively non-saturable even at high expression levels.
Collapse
Affiliation(s)
- Matthew H Baer
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Sean M Cascarina
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Kacy R Paul
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Eric D Ross
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA.
| |
Collapse
|
2
|
Inokuma K, Toyohara K, Hamada T, Kondo A, Hasunuma T. One-pot synthesis of cellobiose from sucrose using sucrose phosphorylase and cellobiose phosphorylase co-displaying Pichia pastoris as a reusable whole-cell biocatalyst. Sci Rep 2024; 14:18540. [PMID: 39122907 PMCID: PMC11315685 DOI: 10.1038/s41598-024-69676-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Accepted: 08/07/2024] [Indexed: 08/12/2024] Open
Abstract
Cellobiose has received increasing attention in various industrial sectors, ranging from food and feed to cosmetics. The development of large-scale cellobiose applications requires a cost-effective production technology as currently used methods based on cellulose hydrolysis are costly. Here, a one-pot synthesis of cellobiose from sucrose was conducted using a recombinant Pichia pastoris strain as a reusable whole-cell biocatalyst. Thermophilic sucrose phosphorylase from Bifidobacterium longum (BlSP) and cellobiose phosphorylase from Clostridium stercorarium (CsCBP) were co-displayed on the cell surface of P. pastoris via a glycosylphosphatidylinositol-anchoring system. Cells of the BlSP and CsCBP co-displaying P. pastoris strain were used as whole-cell biocatalysts to convert sucrose to cellobiose with commercial thermophilic xylose isomerase. Cellobiose productivity significantly improved with yeast cells grown on glycerol compared to glucose-grown cells. In one-pot bioconversion using glycerol-grown yeast cells, approximately 81.2 g/L of cellobiose was produced from 100 g/L of sucrose, corresponding to 81.2% of the theoretical maximum yield, within 24 h at 60 °C. Moreover, recombinant yeast cells maintained a cellobiose titer > 80 g/L, even after three consecutive cell-recycling one-pot bioconversion cycles. These results indicated that one-pot bioconversion using yeast cells displaying two phosphorylases as whole-cell catalysts is a promising approach for cost-effective cellobiose production.
Collapse
Affiliation(s)
- Kentaro Inokuma
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai-Cho, Nada-Ku, Kobe, 657-8501, Japan
| | - Kiyotsuna Toyohara
- Iwakuni Research Center, TEIJIN Limited, 2-1 Hinode, Iwakuni, Yamagichi, 740-8511, Japan
| | - Tomoya Hamada
- Iwakuni Research Center, TEIJIN Limited, 2-1 Hinode, Iwakuni, Yamagichi, 740-8511, Japan
| | - Akihiko Kondo
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai-Cho, Nada-Ku, Kobe, 657-8501, Japan
- Engineering Biology Research Center, Kobe University, 1-1 Rokkodai-Cho, Nada-Ku, Kobe, 657-8501, Japan
- Biomass Engineering Program, RIKEN, 1-7-22 Suehiro-Cho, Tsurumi-Ku, Yokohama, Kanagawa, 230-0045, Japan
| | - Tomohisa Hasunuma
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai-Cho, Nada-Ku, Kobe, 657-8501, Japan.
- Engineering Biology Research Center, Kobe University, 1-1 Rokkodai-Cho, Nada-Ku, Kobe, 657-8501, Japan.
| |
Collapse
|
3
|
Neal ML, Shukla N, Mast FD, Farré JC, Pacio TM, Raney-Plourde KE, Prasad S, Subramani S, Aitchison JD. Automated, image-based quantification of peroxisome characteristics with perox-per-cell. Bioinformatics 2024; 40:btae442. [PMID: 39001800 PMCID: PMC11269463 DOI: 10.1093/bioinformatics/btae442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 06/13/2024] [Accepted: 07/12/2024] [Indexed: 07/15/2024] Open
Abstract
SUMMARY perox-per-cell automates cumbersome, image-based data collection tasks often encountered in peroxisome research. The software processes microscopy images to quantify peroxisome features in yeast cells. It uses off-the-shelf image processing tools to automatically segment cells and peroxisomes and then outputs quantitative metrics including peroxisome counts per cell and spatial areas. In validation tests, we found that perox-per-cell output agrees well with manually quantified peroxisomal counts and cell instances, thereby enabling high-throughput quantification of peroxisomal characteristics. AVAILABILITY AND IMPLEMENTATION The software is coded in Python. Compiled executables and source code are available at https://github.com/AitchisonLab/perox-per-cell. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
Collapse
Affiliation(s)
- Maxwell L Neal
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA 98109, United States
| | - Nandini Shukla
- Department of Molecular Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, United States
| | - Fred D Mast
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA 98109, United States
| | - Jean-Claude Farré
- Department of Molecular Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, United States
| | - Therese M Pacio
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA 98109, United States
| | - Katelyn E Raney-Plourde
- Department of Molecular Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, United States
| | - Sumedh Prasad
- Department of Molecular Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, United States
| | - Suresh Subramani
- Department of Molecular Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, United States
| | - John D Aitchison
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA 98109, United States
- Departments of Pediatrics and Biochemistry, University of Washington, Seattle, WA 98195, United States
| |
Collapse
|
4
|
Szücs B, Selvan R, Lisby M. High-throughput classification of S. cerevisiae tetrads using deep learning. Yeast 2024; 41:423-436. [PMID: 38850080 DOI: 10.1002/yea.3965] [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: 01/15/2024] [Revised: 04/17/2024] [Accepted: 05/14/2024] [Indexed: 06/09/2024] Open
Abstract
Meiotic crossovers play a vital role in proper chromosome segregation and evolution of most sexually reproducing organisms. Meiotic recombination can be visually observed in Saccharomyces cerevisiae tetrads using linked spore-autonomous fluorescent markers placed at defined intervals within the genome, which allows for analysis of meiotic segregation without the need for tetrad dissection. To automate the analysis, we developed a deep learning-based image recognition and classification pipeline for high-throughput tetrad detection and meiotic crossover classification. As a proof of concept, we analyzed a large image data set from wild-type and selected gene knock-out mutants to quantify crossover frequency, interference, chromosome missegregation, and gene conversion events. The deep learning-based method has the potential to accelerate the discovery of new genes involved in meiotic recombination in S. cerevisiae such as the underlying factors controlling crossover frequency and interference.
Collapse
Affiliation(s)
- Balint Szücs
- Section for Functional Genomics, Department of Biology, University of Copenhagen, Copenhagen, Denmark
- Center for Chromosome Stability, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Raghavendra Selvan
- Department of Computer Science, University of Copenhagen, Copenhagen, Denmark
- Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
| | - Michael Lisby
- Section for Functional Genomics, Department of Biology, University of Copenhagen, Copenhagen, Denmark
- Center for Chromosome Stability, Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
5
|
Chappleboim M, Naveh-Tassa S, Carmi M, Levy Y, Barkai N. Ordered and disordered regions of the Origin Recognition Complex direct differential in vivo binding at distinct motif sequences. Nucleic Acids Res 2024; 52:5720-5731. [PMID: 38597680 PMCID: PMC11162778 DOI: 10.1093/nar/gkae249] [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: 01/10/2024] [Revised: 03/16/2024] [Accepted: 04/09/2024] [Indexed: 04/11/2024] Open
Abstract
The Origin Recognition Complex (ORC) seeds replication-fork formation by binding to DNA replication origins, which in budding yeast contain a 17bp DNA motif. High resolution structure of the ORC-DNA complex revealed two base-interacting elements: a disordered basic patch (Orc1-BP4) and an insertion helix (Orc4-IH). To define the ORC elements guiding its DNA binding in vivo, we mapped genomic locations of 38 designed ORC mutants, revealing that different ORC elements guide binding at different sites. At silencing-associated sites lacking the motif, ORC binding and activity were fully explained by a BAH domain. Within replication origins, we reveal two dominating motif variants showing differential binding modes and symmetry: a non-repetitive motif whose binding requires Orc1-BP4 and Orc4-IH, and a repetitive one where another basic patch, Orc1-BP3, can replace Orc4-IH. Disordered basic patches are therefore key for ORC-motif binding in vivo, and we discuss how these conserved, minor-groove interacting elements can guide specific ORC-DNA recognition.
Collapse
Affiliation(s)
- Michal Chappleboim
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Segev Naveh-Tassa
- Department of Chemical and structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Miri Carmi
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Yaakov Levy
- Department of Chemical and structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Naama Barkai
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| |
Collapse
|
6
|
Namba S, Moriya H. Toxicity of the model protein 3×GFP arises from degradation overload, not from aggregate formation. J Cell Sci 2024; 137:jcs261977. [PMID: 38766715 DOI: 10.1242/jcs.261977] [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: 01/31/2024] [Accepted: 05/09/2024] [Indexed: 05/22/2024] Open
Abstract
Although protein aggregation can cause cytotoxicity, such aggregates can also form to mitigate cytotoxicity from misfolded proteins, although the nature of these contrasting aggregates remains unclear. We previously found that overproduction (op) of a three green fluorescent protein-linked protein (3×GFP) induces giant aggregates and is detrimental to growth. Here, we investigated the mechanism of growth inhibition by 3×GFP-op using non-aggregative 3×MOX-op as a control in Saccharomyces cerevisiae. The 3×GFP aggregates were induced by misfolding, and 3×GFP-op had higher cytotoxicity than 3×MOX-op because it perturbed the ubiquitin-proteasome system. Static aggregates formed by 3×GFP-op dynamically trapped Hsp70 family proteins (Ssa1 and Ssa2 in yeast), causing the heat-shock response. Systematic analysis of mutants deficient in the protein quality control suggested that 3×GFP-op did not cause a critical Hsp70 depletion and aggregation functioned in the direction of mitigating toxicity. Artificial trapping of essential cell cycle regulators into 3×GFP aggregates caused abnormalities in the cell cycle. In conclusion, the formation of the giant 3×GFP aggregates itself is not cytotoxic, as it does not entrap and deplete essential proteins. Rather, it is productive, inducing the heat-shock response while preventing an overload to the degradation system.
Collapse
Affiliation(s)
- Shotaro Namba
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, Okayama, Japan
| | - Hisao Moriya
- Faculty of Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| |
Collapse
|
7
|
Neal ML, Shukla N, Mast FD, Farré JC, Pacio TM, Raney-Plourde KE, Prasad S, Subramani S, Aitchison JD. Automated, image-based quantification of peroxisome characteristics with perox-per-cell. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.08.588597. [PMID: 38645222 PMCID: PMC11030360 DOI: 10.1101/2024.04.08.588597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
perox-per-cell automates cumbersome, image-based data collection tasks often encountered in peroxisome research. The software processes microscopy images to quantify peroxisome features in yeast cells. It uses off-the-shelf image processing tools to automatically segment cells and peroxisomes and then outputs quantitative metrics including peroxisome counts per cell and spatial areas. In validation tests, we found that perox-per-cell output agrees well with manually-quantified peroxisomal counts and cell instances, thereby enabling high-throughput quantification of peroxisomal characteristics. The software is available at https://github.com/AitchisonLab/perox-per-cell.
Collapse
|
8
|
Hernandez AC, Ortiz S, Betancur LI, Dojčilović R, Picco A, Kaksonen M, Oliva B, Gallego O. PyF2F: a robust and simplified fluorophore-to-fluorophore distance measurement tool for Protein interactions from Imaging Complexes after Translocation experiments. NAR Genom Bioinform 2024; 6:lqae027. [PMID: 38486885 PMCID: PMC10939353 DOI: 10.1093/nargab/lqae027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 01/31/2024] [Accepted: 02/27/2024] [Indexed: 03/17/2024] Open
Abstract
Structural knowledge of protein assemblies in their physiological environment is paramount to understand cellular functions at the molecular level. Protein interactions from Imaging Complexes after Translocation (PICT) is a live-cell imaging technique for the structural characterization of macromolecular assemblies in living cells. PICT relies on the measurement of the separation between labelled molecules using fluorescence microscopy and cell engineering. Unfortunately, the required computational tools to extract molecular distances involve a variety of sophisticated software programs that challenge reproducibility and limit their implementation to highly specialized researchers. Here we introduce PyF2F, a Python-based software that provides a workflow for measuring molecular distances from PICT data, with minimal user programming expertise. We used a published dataset to validate PyF2F's performance.
Collapse
Affiliation(s)
- Altair C Hernandez
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra, Barcelona 08005, Catalonia, Spain
| | - Sebastian Ortiz
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra, Barcelona 08005, Catalonia, Spain
| | - Laura I Betancur
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra, Barcelona 08005, Catalonia, Spain
| | - Radovan Dojčilović
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra, Barcelona 08005, Catalonia, Spain
| | - Andrea Picco
- Department of Biochemistry, University of Geneva, 1205 Genève, Switzerland
| | - Marko Kaksonen
- Department of Biochemistry, University of Geneva, 1205 Genève, Switzerland
| | - Baldo Oliva
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra, Barcelona 08005, Catalonia, Spain
| | - Oriol Gallego
- Department of Medicine and Life Sciences, Universitat Pompeu Fabra, Barcelona 08005, Catalonia, Spain
| |
Collapse
|
9
|
Sanyal S, Kouznetsova A, Ström L, Björkegren C. A system for inducible mitochondria-specific protein degradation in vivo. Nat Commun 2024; 15:1454. [PMID: 38365818 PMCID: PMC10873288 DOI: 10.1038/s41467-024-45819-6] [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: 02/24/2023] [Accepted: 02/05/2024] [Indexed: 02/18/2024] Open
Abstract
Targeted protein degradation systems developed for eukaryotes employ cytoplasmic machineries to perform proteolysis. This has prevented mitochondria-specific analysis of proteins that localize to multiple locations, for example, the mitochondria and the nucleus. Here, we present an inducible mitochondria-specific protein degradation system in Saccharomyces cerevisiae based on the Mesoplasma florum Lon (mf-Lon) protease and its corresponding ssrA tag (called PDT). We show that mitochondrially targeted mf-Lon protease efficiently and selectively degrades a PDT-tagged reporter protein localized to the mitochondrial matrix. The degradation can be induced by depleting adenine from the medium, and tuned by altering the promoter strength of the MF-LON gene. We furthermore demonstrate that mf-Lon specifically degrades endogenous, PDT-tagged mitochondrial proteins. Finally, we show that mf-Lon-dependent PDT degradation can also be achieved in human mitochondria. In summary, this system provides an efficient tool to selectively analyze the mitochondrial function of dually localized proteins.
Collapse
Affiliation(s)
- Swastika Sanyal
- Karolinska Institutet, Department of Biosciences and Nutrition, Neo, Hälsovägen 7c, 141 83, Huddinge, Sweden.
| | - Anna Kouznetsova
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77, Stockholm, Sweden
| | - Lena Ström
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77, Stockholm, Sweden
| | - Camilla Björkegren
- Karolinska Institutet, Department of Cell and Molecular Biology, Biomedicum, Tomtebodavägen 16, 171 77, Stockholm, Sweden.
| |
Collapse
|
10
|
Jan M, Spangaro A, Lenartowicz M, Mattiazzi Usaj M. From pixels to insights: Machine learning and deep learning for bioimage analysis. Bioessays 2024; 46:e2300114. [PMID: 38058114 DOI: 10.1002/bies.202300114] [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: 06/24/2023] [Revised: 10/25/2023] [Accepted: 11/13/2023] [Indexed: 12/08/2023]
Abstract
Bioimage analysis plays a critical role in extracting information from biological images, enabling deeper insights into cellular structures and processes. The integration of machine learning and deep learning techniques has revolutionized the field, enabling the automated, reproducible, and accurate analysis of biological images. Here, we provide an overview of the history and principles of machine learning and deep learning in the context of bioimage analysis. We discuss the essential steps of the bioimage analysis workflow, emphasizing how machine learning and deep learning have improved preprocessing, segmentation, feature extraction, object tracking, and classification. We provide examples that showcase the application of machine learning and deep learning in bioimage analysis. We examine user-friendly software and tools that enable biologists to leverage these techniques without extensive computational expertise. This review is a resource for researchers seeking to incorporate machine learning and deep learning in their bioimage analysis workflows and enhance their research in this rapidly evolving field.
Collapse
Affiliation(s)
- Mahta Jan
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Canada
| | - Allie Spangaro
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Canada
| | - Michelle Lenartowicz
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Canada
| | - Mojca Mattiazzi Usaj
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Canada
| |
Collapse
|
11
|
Xiao Q, Wang Y, Fan J, Yi Z, Hong H, Xie X, Huang QA, Fu J, Ouyang J, Zhao X, Wang Z, Zhu Z. A computer vision and residual neural network (ResNet) combined method for automated and accurate yeast replicative aging analysis of high-throughput microfluidic single-cell images. Biosens Bioelectron 2024; 244:115807. [PMID: 37948914 DOI: 10.1016/j.bios.2023.115807] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 10/17/2023] [Accepted: 10/30/2023] [Indexed: 11/12/2023]
Abstract
With the rapid development of microfluidic platforms in high-throughput single-cell culturing, laborious operation to manipulate massive budding yeast cells (Saccharomyces cerevisiae) in replicative aging studies has been greatly simplified and automated. As a result, large datasets of microscopy images bring challenges to fast and accurately determine yeast replicative lifespan (RLS), which is the most important parameter to study cell aging. Based on our microfluidic diploid yeast long-term culturing (DYLC) chip that features 1100 traps to immobilize single cells and record their proliferation and aging via time-lapse imaging, herein, a dedicated algorithm combined with computer vision and residual neural network (ResNet) was presented to efficiently process tremendous micrographs in a high-throughput and automated manner. The image-processing algorithm includes following pivotal steps: (i) segmenting multi-trap micrographs into time-lapse single-trap sub-images, (ii) labeling 8 yeast budding features and training the 18-layer ResNet, (iii) converting the ResNet predictions in analog values into digital signals, (iv) recognizing cell dynamic events, and (v) determining yeast RLS and budding time interval (BTI) ultimately. The ResNet algorithm achieved high F1 scores (over 92%) demonstrating the effectiveness and accuracy in the recognition of yeast budding events, such as bud appearance, daughter dissection and cell death. Therefore, the results conduct that similar deep learning algorithms could be tailored to analyze high-throughput microscopy images and extract multiple cell behaviors in microfluidic single-cell analysis.
Collapse
Affiliation(s)
- Qin Xiao
- Southeast University, School of Integrated Circuits, School of Electronic Science and Engineering, Key Laboratory of MEMS of Ministry of Education, Sipailou 2, Nanjing, 210096, China
| | - Yingying Wang
- Southeast University, School of Integrated Circuits, School of Electronic Science and Engineering, Key Laboratory of MEMS of Ministry of Education, Sipailou 2, Nanjing, 210096, China
| | - Juncheng Fan
- Southeast University, School of Integrated Circuits, School of Electronic Science and Engineering, Key Laboratory of MEMS of Ministry of Education, Sipailou 2, Nanjing, 210096, China
| | - Zhenxiang Yi
- Southeast University, School of Integrated Circuits, School of Electronic Science and Engineering, Key Laboratory of MEMS of Ministry of Education, Sipailou 2, Nanjing, 210096, China
| | - Hua Hong
- Southeast University, School of Integrated Circuits, School of Electronic Science and Engineering, Key Laboratory of MEMS of Ministry of Education, Sipailou 2, Nanjing, 210096, China
| | - Xiao Xie
- Southeast University, School of Integrated Circuits, School of Electronic Science and Engineering, Key Laboratory of MEMS of Ministry of Education, Sipailou 2, Nanjing, 210096, China
| | - Qing-An Huang
- Southeast University, School of Integrated Circuits, School of Electronic Science and Engineering, Key Laboratory of MEMS of Ministry of Education, Sipailou 2, Nanjing, 210096, China
| | - Jiaming Fu
- Nanjing Forestry University, College of Chemical Engineering, Longpan Road 159, Nanjing, 210037, China
| | - Jia Ouyang
- Nanjing Forestry University, College of Chemical Engineering, Longpan Road 159, Nanjing, 210037, China
| | - Xiangwei Zhao
- Southeast University, School of Biological Science and Medical Engineering, State Key Laboratory of Digital Medical Engineering, Sipailou 2, Nanjing, 210096, China
| | - Zixin Wang
- Sun Yat-Sen University, School of Electronics and Information Technology, Waihuan Dong Road 132, Guangzhou, 510006, China.
| | - Zhen Zhu
- Southeast University, School of Integrated Circuits, School of Electronic Science and Engineering, Key Laboratory of MEMS of Ministry of Education, Sipailou 2, Nanjing, 210096, China.
| |
Collapse
|
12
|
Le Bec M, Pouzet S, Cordier C, Barral S, Scolari V, Sorre B, Banderas A, Hersen P. Optogenetic spatial patterning of cooperation in yeast populations. Nat Commun 2024; 15:75. [PMID: 38168087 PMCID: PMC10761962 DOI: 10.1038/s41467-023-44379-5] [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: 05/17/2023] [Accepted: 12/11/2023] [Indexed: 01/05/2024] Open
Abstract
Microbial communities are shaped by complex metabolic interactions such as cooperation and competition for resources. Methods to control such interactions could lead to major advances in our ability to better engineer microbial consortia for synthetic biology applications. Here, we use optogenetics to control SUC2 invertase production in yeast, thereby shaping spatial assortment of cooperator and cheater cells. Yeast cells behave as cooperators (i.e., transform sucrose into hexose, a public good) upon blue light illumination or cheaters (i.e., consume hexose produced by cooperators to grow) in the dark. We show that cooperators benefit best from the hexoses they produce when their domain size is constrained between two cut-off length-scales. From an engineering point of view, the system behaves as a bandpass filter. The lower limit is the trace of cheaters' competition for hexoses, while the upper limit is defined by cooperators' competition for sucrose. Cooperation mostly occurs at the frontiers with cheater cells, which not only compete for hexoses but also cooperate passively by letting sucrose reach cooperators. We anticipate that this optogenetic method could be applied to shape metabolic interactions in a variety of microbial ecosystems.
Collapse
Affiliation(s)
- Matthias Le Bec
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physico Chimie Curie, 75005, Paris, France
| | - Sylvain Pouzet
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physico Chimie Curie, 75005, Paris, France
| | - Céline Cordier
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physico Chimie Curie, 75005, Paris, France
| | - Simon Barral
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physico Chimie Curie, 75005, Paris, France
| | - Vittore Scolari
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physico Chimie Curie, 75005, Paris, France
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR3664, Laboratoire Dynamique du Noyau, 75005, Paris, France
| | - Benoit Sorre
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physico Chimie Curie, 75005, Paris, France
| | - Alvaro Banderas
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physico Chimie Curie, 75005, Paris, France.
| | - Pascal Hersen
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR168, Laboratoire Physico Chimie Curie, 75005, Paris, France.
| |
Collapse
|
13
|
Lu AX, Moses AM. Using Dimensionality Reduction to Visualize Phenotypic Changes in High-Throughput Microscopy. Methods Mol Biol 2024; 2800:217-229. [PMID: 38709487 DOI: 10.1007/978-1-0716-3834-7_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2024]
Abstract
High-throughput microscopy has enabled screening of cell phenotypes at unprecedented scale. Systematic identification of cell phenotype changes (such as cell morphology and protein localization changes) is a major analysis goal. Because cell phenotypes are high-dimensional, unbiased approaches to detect and visualize the changes in phenotypes are still needed. Here, we suggest that changes in cellular phenotype can be visualized in reduced dimensionality representations of the image feature space. We describe a freely available analysis pipeline to visualize changes in protein localization in feature spaces obtained from deep learning. As an example, we use the pipeline to identify changes in subcellular localization after the yeast GFP collection was treated with hydroxyurea.
Collapse
Affiliation(s)
- Alex X Lu
- Microsoft Research New England, Cambridge, MA, USA.
| | - Alan M Moses
- Department of Cell & Systems Biology, University of Toronto, Toronto, Canada
| |
Collapse
|
14
|
Shu T, Mitra G, Alberts J, Viana MP, Levy ED, Hocky GM, Holt LJ. Mesoscale molecular assembly is favored by the active, crowded cytoplasm. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.19.558334. [PMID: 37781612 PMCID: PMC10541124 DOI: 10.1101/2023.09.19.558334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
The mesoscale organization of molecules into membraneless biomolecular condensates is emerging as a key mechanism of rapid spatiotemporal control in cells1. Principles of biomolecular condensation have been revealed through in vitro reconstitution2. However, intracellular environments are much more complex than test-tube environments: They are viscoelastic, highly crowded at the mesoscale, and are far from thermodynamic equilibrium due to the constant action of energy-consuming processes3. We developed synDrops, a synthetic phase separation system, to study how the cellular environment affects condensate formation. Three key features enable physical analysis: synDrops are inducible, bioorthogonal, and have well-defined geometry. This design allows kinetic analysis of synDrop assembly and facilitates computational simulation of the process. We compared experiments and simulations to determine that macromolecular crowding promotes condensate nucleation but inhibits droplet growth through coalescence. ATP-dependent cellular activities help overcome the frustration of growth. In particular, actomyosin dynamics potentiate droplet growth by reducing confinement and elasticity in the mammalian cytoplasm, thereby enabling synDrop coarsening. Our results demonstrate that mesoscale molecular assembly is favored by the combined effects of crowding and active matter in the cytoplasm. These results move toward a better predictive understanding of condensate formation in vivo.
Collapse
Affiliation(s)
- Tong Shu
- Institute for Systems Genetics, NYU Langone Medical Center, 435 E 30th Street, New York, NY 10016, USA
| | - Gaurav Mitra
- Department of Chemistry, New York University, New York, New York, USA
| | | | | | - Emmanuel D. Levy
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Glen M. Hocky
- Department of Chemistry, New York University, New York, New York, USA
- Simons Center for Computational Physical Chemistry, New York University, New York, New York, USA
| | - Liam J. Holt
- Institute for Systems Genetics, NYU Langone Medical Center, 435 E 30th Street, New York, NY 10016, USA
| |
Collapse
|
15
|
Gu Y, Alam S, Oliferenko S. Peroxisomal compartmentalization of amino acid biosynthesis reactions imposes an upper limit on compartment size. Nat Commun 2023; 14:5544. [PMID: 37684233 PMCID: PMC10491753 DOI: 10.1038/s41467-023-41347-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Accepted: 08/31/2023] [Indexed: 09/10/2023] Open
Abstract
Cellular metabolism relies on just a few redox cofactors. Selective compartmentalization may prevent competition between metabolic reactions requiring the same cofactor. Is such compartmentalization necessary for optimal cell function? Is there an optimal compartment size? Here we probe these fundamental questions using peroxisomal compartmentalization of the last steps of lysine and histidine biosynthesis in the fission yeast Schizosaccharomyces japonicus. We show that compartmentalization of these NAD+ dependent reactions together with a dedicated NADH/NAD+ recycling enzyme supports optimal growth when an increased demand for anabolic reactions taxes cellular redox balance. In turn, compartmentalization constrains the size of individual organelles, with larger peroxisomes accumulating all the required enzymes but unable to support both biosynthetic reactions at the same time. Our reengineering and physiological experiments indicate that compartmentalized biosynthetic reactions are sensitive to the size of the compartment, likely due to scaling-dependent changes within the system, such as enzyme packing density.
Collapse
Affiliation(s)
- Ying Gu
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.
- Randall Centre for Cell and Molecular Biophysics, School of Basic and Medical Biosciences, King's College London, London, SE1 1UL, UK.
| | - Sara Alam
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
- Randall Centre for Cell and Molecular Biophysics, School of Basic and Medical Biosciences, King's College London, London, SE1 1UL, UK
- Medical Research Council London Institute of Medical Sciences, Du Cane Road, London, W12 0NN, UK
| | - Snezhana Oliferenko
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.
- Randall Centre for Cell and Molecular Biophysics, School of Basic and Medical Biosciences, King's College London, London, SE1 1UL, UK.
| |
Collapse
|
16
|
Das S, Singh A, Shah P. Evaluating single-cell variability in proteasomal decay. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.22.554358. [PMID: 37662347 PMCID: PMC10473619 DOI: 10.1101/2023.08.22.554358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Gene expression is a stochastic process that leads to variability in mRNA and protein abundances even within an isogenic population of cells grown in the same environment. This variation, often called gene-expression noise, has typically been attributed to transcriptional and translational processes while ignoring the contributions of protein decay variability across cells. Here we estimate the single-cell protein decay rates of two degron GFPs in Saccharomyces cerevisiae using time-lapse microscopy. We find substantial cell-to-cell variability in the decay rates of the degron GFPs. We evaluate cellular features that explain the variability in the proteasomal decay and find that the amount of 20s catalytic beta subunit of the proteasome marginally explains the observed variability in the degron GFP half-lives. We propose alternate hypotheses that might explain the observed variability in the decay of the two degron GFPs. Overall, our study highlights the importance of studying the kinetics of the decay process at single-cell resolution and that decay rates vary at the single-cell level, and that the decay process is stochastic. A complex model of decay dynamics must be included when modeling stochastic gene expression to estimate gene expression noise.
Collapse
Affiliation(s)
| | - Abhyudai Singh
- Department of Electrical and Computer Engineering, Biomedical Engineering, University of Delaware
| | | |
Collapse
|
17
|
Jonas F, Carmi M, Krupkin B, Steinberger J, Brodsky S, Jana T, Barkai N. The molecular grammar of protein disorder guiding genome-binding locations. Nucleic Acids Res 2023; 51:4831-4844. [PMID: 36938874 PMCID: PMC10250222 DOI: 10.1093/nar/gkad184] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 01/25/2023] [Accepted: 03/15/2023] [Indexed: 03/21/2023] Open
Abstract
Intrinsically disordered regions (IDRs) direct transcription factors (TFs) towards selected genomic occurrences of their binding motif, as exemplified by budding yeast's Msn2. However, the sequence basis of IDR-directed TF binding selectivity remains unknown. To reveal this sequence grammar, we analyze the genomic localizations of >100 designed IDR mutants, each carrying up to 122 mutations within this 567-AA region. Our data points at multivalent interactions, carried by hydrophobic-mostly aliphatic-residues dispersed within a disordered environment and independent of linear sequence motifs, as the key determinants of Msn2 genomic localization. The implications of our results for the mechanistic basis of IDR-based TF binding preferences are discussed.
Collapse
Affiliation(s)
- Felix Jonas
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Miri Carmi
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Beniamin Krupkin
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Joseph Steinberger
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sagie Brodsky
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Tamar Jana
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Naama Barkai
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| |
Collapse
|
18
|
Arlt H, Raman B, Filali-Mouncef Y, Hu Y, Leytens A, Hardenberg R, Guimarães R, Kriegenburg F, Mari M, Smaczynska-de Rooij II, Ayscough KR, Dengjel J, Ungermann C, Reggiori F. The dynamin Vps1 mediates Atg9 transport to the sites of autophagosome formation. J Biol Chem 2023; 299:104712. [PMID: 37060997 DOI: 10.1016/j.jbc.2023.104712] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 03/14/2023] [Accepted: 04/06/2023] [Indexed: 04/17/2023] Open
Abstract
Autophagy is a key process in eukaryotes to maintain cellular homeostasis by delivering cellular components to lysosomes/vacuoles for degradation and reuse of the resulting metabolites. Membrane rearrangements and trafficking events are mediated by the core machinery of autophagy-related (Atg) proteins, which carry out a variety of functions. How Atg9, a lipid scramblase and the only conserved transmembrane protein within this core Atg machinery, is trafficked during autophagy remained largely unclear. Here, we addressed this question in yeast Saccharomyces cerevisiae and found that retromer complex and dynamin Vps1 mutants alter Atg9 subcellular distribution and severely impair the autophagic flux by affecting two separate autophagy steps. We provide evidence that Vps1 interacts with Atg9 at Atg9 reservoirs. In the absence of Vps1, Atg9 fails to reach the sites of autophagosome formation, and this results in an autophagy defect. The function of Vps1 in autophagy requires its GTPase activity. Moreover, Vps1 point mutants associated with human diseases such as microcytic anemia and Charcot-Marie-Tooth are unable to sustain autophagy and affect Atg9 trafficking. Together, our data provide novel insights on the role of dynamins in Atg9 trafficking and suggest that a defect in this autophagy step could contribute to severe human pathologies.
Collapse
Affiliation(s)
- Henning Arlt
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; University of Osnabrück, Department of Biology/Chemistry, Biochemistry section, Barbarastrasse 13, 49076 Osnabrück, Germany
| | - Babu Raman
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Yasmina Filali-Mouncef
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Yan Hu
- Department of Biomedicine, Aarhus University, Ole Worms Allé 4, 8000 Aarhus C, Denmark
| | - Alexandre Leytens
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Ralph Hardenberg
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Rodrigo Guimarães
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Franziska Kriegenburg
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Muriel Mari
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedicine, Aarhus University, Ole Worms Allé 4, 8000 Aarhus C, Denmark
| | | | - Kathryn R Ayscough
- Department of Biomedical Sciences, University of Sheffield, Sheffield, S10 2TN, United Kingdom
| | - Jörn Dengjel
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Christian Ungermann
- University of Osnabrück, Department of Biology/Chemistry, Biochemistry section, Barbarastrasse 13, 49076 Osnabrück, Germany
| | - Fulvio Reggiori
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedicine, Aarhus University, Ole Worms Allé 4, 8000 Aarhus C, Denmark; Aarhus Institute of Advanced Studies (AIAS), Aarhus University, Høegh-Guldbergs Gade 6B, 8000 Aarhus C, Denmark.
| |
Collapse
|
19
|
Kitahara Y, Itani A, Ohtomo K, Oda Y, Takahashi Y, Okamura M, Mizoshiri M, Shida Y, Nakamura T, Harakawa R, Iwahashi M, Ogasawara W. The monitoring of oil production process by deep learning based on morphology in oleaginous yeasts. Appl Microbiol Biotechnol 2023; 107:915-929. [PMID: 36576569 DOI: 10.1007/s00253-022-12338-7] [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: 10/18/2022] [Revised: 12/08/2022] [Accepted: 12/10/2022] [Indexed: 12/29/2022]
Abstract
BACKGROUND Monitoring jar fermenter-cultured microorganisms in real time is important for controlling productivity of bioproducts in large-scale cultivation settings. Morphological data is used to understand the growth and fermentation states of these microorganisms during monitoring. Oleaginous yeasts are used for their high productivity of single-cell oils but the relationship between lipid productivity and morphology has not been elucidated in these organisms. RESULTS In this study, we investigated the relationship between the morphology of oleaginous yeasts (Lipomyces starkeyi and Rhodosporidium toruloides were used) and their cultivation state in a large-scale cultivation setting using a real-time monitoring system. We combined this with deep learning by feeding a large amount of high-definition cell images obtained from the monitoring system to a deep learning algorithm. Our results showed that the cell images could be grouped into 7 distinct groups and that a strong correlation existed between each group and its biochemical activity (growth and oil-productivity). CONCLUSIONS This is the first report describing the morphological variations of oleaginous yeasts in a large-scale cultivation, and describes a promising new avenue for improving productivity of microorganisms in large-scale cultivation through the use of a real-time monitoring system combined with deep learning. KEY POINTS • A real-time monitoring system followed the morphological change of oleaginous yeasts. • Deep learning grouped them into 7 distinct groups based on their morphology. • A correlation between the cultivation state and the shape of the yeast was observed.
Collapse
Affiliation(s)
- Yukina Kitahara
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata, 940-2188, Japan
| | - Ayaka Itani
- Department of Bioengineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata, 940-2188, Japan
| | - Kazuma Ohtomo
- Department of Information Science and Control Engineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata, 940-2188, Japan
| | - Yosuke Oda
- Department of Mechanical Engineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata, 940-2188, Japan
| | - Yuka Takahashi
- Department of Bioengineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata, 940-2188, Japan
| | - Makoto Okamura
- NRI System Techno Ltd, 4-4-1 Minato Mirai, Nishi-Ku, Yokohama, 220-0012, Japan
| | - Mizue Mizoshiri
- Department of Mechanical Engineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata, 940-2188, Japan
| | - Yosuke Shida
- Department of Bioengineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata, 940-2188, Japan
| | - Toru Nakamura
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata, 940-2188, Japan
| | - Ryosuke Harakawa
- Department of Electrical Electronics and Information Engineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata, 940-2188, Japan
| | - Masahiro Iwahashi
- Department of Electrical Electronics and Information Engineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata, 940-2188, Japan
| | - Wataru Ogasawara
- Department of Science of Technology Innovation, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata, 940-2188, Japan. .,Department of Bioengineering, Nagaoka University of Technology, 1603-1, Kamitomioka, Nagaoka, Niigata, 940-2188, Japan.
| |
Collapse
|
20
|
Scherr T, Seiffarth J, Wollenhaupt B, Neumann O, Schilling MP, Kohlheyer D, Scharr H, Nöh K, Mikut R. microbeSEG: A deep learning software tool with OMERO data management for efficient and accurate cell segmentation. PLoS One 2022; 17:e0277601. [PMID: 36445903 PMCID: PMC9707790 DOI: 10.1371/journal.pone.0277601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 11/01/2022] [Indexed: 12/02/2022] Open
Abstract
In biotechnology, cell growth is one of the most important properties for the characterization and optimization of microbial cultures. Novel live-cell imaging methods are leading to an ever better understanding of cell cultures and their development. The key to analyzing acquired data is accurate and automated cell segmentation at the single-cell level. Therefore, we present microbeSEG, a user-friendly Python-based cell segmentation tool with a graphical user interface and OMERO data management. microbeSEG utilizes a state-of-the-art deep learning-based segmentation method and can be used for instance segmentation of a wide range of cell morphologies and imaging techniques, e.g., phase contrast or fluorescence microscopy. The main focus of microbeSEG is a comprehensible, easy, efficient, and complete workflow from the creation of training data to the final application of the trained segmentation model. We demonstrate that accurate cell segmentation results can be obtained within 45 minutes of user time. Utilizing public segmentation datasets or pre-labeling further accelerates the microbeSEG workflow. This opens the door for accurate and efficient data analysis of microbial cultures.
Collapse
Affiliation(s)
- Tim Scherr
- Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
- * E-mail: (TS); (KN); (RM)
| | - Johannes Seiffarth
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
- Computational Systems Biology (AVT.CSB), RWTH Aachen University, Aachen, Germany
| | - Bastian Wollenhaupt
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Oliver Neumann
- Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
| | - Marcel P. Schilling
- Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
| | - Dietrich Kohlheyer
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Hanno Scharr
- Institute of Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute for Advanced Simulation, IAS-8: Data Analytics and Machine Learning, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Katharina Nöh
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
- * E-mail: (TS); (KN); (RM)
| | - Ralf Mikut
- Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
- * E-mail: (TS); (KN); (RM)
| |
Collapse
|
21
|
Padovani F, Mairhörmann B, Falter-Braun P, Lengefeld J, Schmoller KM. Segmentation, tracking and cell cycle analysis of live-cell imaging data with Cell-ACDC. BMC Biol 2022; 20:174. [PMID: 35932043 PMCID: PMC9356409 DOI: 10.1186/s12915-022-01372-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 07/08/2022] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND High-throughput live-cell imaging is a powerful tool to study dynamic cellular processes in single cells but creates a bottleneck at the stage of data analysis, due to the large amount of data generated and limitations of analytical pipelines. Recent progress on deep learning dramatically improved cell segmentation and tracking. Nevertheless, manual data validation and correction is typically still required and tools spanning the complete range of image analysis are still needed. RESULTS We present Cell-ACDC, an open-source user-friendly GUI-based framework written in Python, for segmentation, tracking and cell cycle annotations. We included state-of-the-art deep learning models for single-cell segmentation of mammalian and yeast cells alongside cell tracking methods and an intuitive, semi-automated workflow for cell cycle annotation of single cells. Using Cell-ACDC, we found that mTOR activity in hematopoietic stem cells is largely independent of cell volume. By contrast, smaller cells exhibit higher p38 activity, consistent with a role of p38 in regulation of cell size. Additionally, we show that, in S. cerevisiae, histone Htb1 concentrations decrease with replicative age. CONCLUSIONS Cell-ACDC provides a framework for the application of state-of-the-art deep learning models to the analysis of live cell imaging data without programming knowledge. Furthermore, it allows for visualization and correction of segmentation and tracking errors as well as annotation of cell cycle stages. We embedded several smart algorithms that make the correction and annotation process fast and intuitive. Finally, the open-source and modularized nature of Cell-ACDC will enable simple and fast integration of new deep learning-based and traditional methods for cell segmentation, tracking, and downstream image analysis. Source code: https://github.com/SchmollerLab/Cell_ACDC.
Collapse
Affiliation(s)
- Francesco Padovani
- Institute of Functional Epigenetics (IFE), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Center Munich, 85764, Munich-Neuherberg, Germany.
| | - Benedikt Mairhörmann
- Institute of Functional Epigenetics (IFE), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Center Munich, 85764, Munich-Neuherberg, Germany
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Center Munich, 85764, Munich-Neuherberg, Germany
| | - Pascal Falter-Braun
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Center Munich, 85764, Munich-Neuherberg, Germany
- Microbe-Host Interactions, Faculty of Biology, Ludwig-Maximilians-University (LMU) München, 82152, Planegg-, Martinsried, Germany
| | - Jette Lengefeld
- Institute of Biotechnology, HiLIFE, University of Helsinki, Biocenter 2, P.O.Box 56 (Viikinkaari 5 D), 00014, Helsinki, Finland
- Department of Biosciences and Nutrition (BioNut), Karolinska Institutet, Huddinge, Sweden
| | - Kurt M Schmoller
- Institute of Functional Epigenetics (IFE), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Center Munich, 85764, Munich-Neuherberg, Germany.
- German Center for Diabetes Research (DZD), 85764, Munich-Neuherberg, Germany.
| |
Collapse
|
22
|
Chappleboim A, Joseph-Strauss D, Gershon O, Friedman N. Transcription feedback dynamics in the wake of cytoplasmic mRNA degradation shutdown. Nucleic Acids Res 2022; 50:5864-5880. [PMID: 35640599 PMCID: PMC9177992 DOI: 10.1093/nar/gkac411] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 05/02/2022] [Accepted: 05/09/2022] [Indexed: 01/02/2023] Open
Abstract
In the last decade, multiple studies demonstrated that cells maintain a balance of mRNA production and degradation, but the mechanisms by which cells implement this balance remain unknown. Here, we monitored cells' total and recently-transcribed mRNA profiles immediately following an acute depletion of Xrn1-the main 5'-3' mRNA exonuclease-which was previously implicated in balancing mRNA levels. We captured the detailed dynamics of the adaptation to rapid degradation of Xrn1 and observed a significant accumulation of mRNA, followed by a delayed global reduction in transcription and a gradual return to baseline mRNA levels. We found that this transcriptional response is not unique to Xrn1 depletion; rather, it is induced earlier when upstream factors in the 5'-3' degradation pathway are perturbed. Our data suggest that the mRNA feedback mechanism monitors the accumulation of inputs to the 5'-3' exonucleolytic pathway rather than its outputs.
Collapse
Affiliation(s)
- Alon Chappleboim
- Alexander Silberman Institute of Life Science, Hebrew University of Jerusalem, Jerusalem 9190401, Israel
- Rachel and Selim Benin School of Computer Science, Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Daphna Joseph-Strauss
- Alexander Silberman Institute of Life Science, Hebrew University of Jerusalem, Jerusalem 9190401, Israel
- Rachel and Selim Benin School of Computer Science, Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Omer Gershon
- Alexander Silberman Institute of Life Science, Hebrew University of Jerusalem, Jerusalem 9190401, Israel
- Rachel and Selim Benin School of Computer Science, Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Nir Friedman
- Alexander Silberman Institute of Life Science, Hebrew University of Jerusalem, Jerusalem 9190401, Israel
- Rachel and Selim Benin School of Computer Science, Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| |
Collapse
|
23
|
Namba S, Kato H, Shigenobu S, Makino T, Moriya H. Massive expression of cysteine-containing proteins causes abnormal elongation of yeast cells by perturbing the proteasome. G3 (BETHESDA, MD.) 2022; 12:jkac106. [PMID: 35485947 PMCID: PMC9157148 DOI: 10.1093/g3journal/jkac106] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 04/25/2022] [Indexed: 12/13/2022]
Abstract
The enhanced green fluorescent protein (EGFP) is considered to be a harmless protein because the critical expression level that causes growth defects is higher than that of other proteins. Here, we found that overexpression of EGFP, but not a glycolytic protein Gpm1, triggered the cell elongation phenotype in the budding yeast Saccharomyces cerevisiae. By the morphological analysis of the cell overexpressing fluorescent protein and glycolytic enzyme variants, we revealed that cysteine content was associated with the cell elongation phenotype. The abnormal cell morphology triggered by overexpression of EGFP was also observed in the fission yeast Schizosaccharomyces pombe. Overexpression of cysteine-containing protein was toxic, especially at high-temperature, while the toxicity could be modulated by additional protein characteristics. Investigation of protein aggregate formation, morphological abnormalities in mutants, and transcriptomic changes that occur upon overexpression of EGFP variants suggested that perturbation of the proteasome by the exposed cysteine of the overexpressed protein causes cell elongation. Overexpression of proteins with relatively low folding properties, such as EGFP, was also found to promote the formation of SHOTA (Seventy kDa Heat shock protein-containing, Overexpression-Triggered Aggregates), an intracellular aggregate that incorporates Hsp70/Ssa1, which induces a heat shock response, while it was unrelated to cell elongation. Evolutionary analysis of duplicated genes showed that cysteine toxicity may be an evolutionary bias to exclude cysteine from highly expressed proteins. The overexpression of cysteine-less moxGFP, the least toxic protein revealed in this study, would be a good model system to understand the physiological state of protein burden triggered by ultimate overexpression of harmless proteins.
Collapse
Affiliation(s)
- Shotaro Namba
- Graduate School of Environmental and Life Sciences, Okayama University, Okayama 700-8530, Japan
| | - Hisaaki Kato
- Graduate School of Environmental and Life Sciences, Okayama University, Okayama 700-8530, Japan
| | - Shuji Shigenobu
- National Institute for Basic Biology, Okazaki, 444-8585 Aichi, Japan
| | - Takashi Makino
- Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi 980-8577, Japan
| | - Hisao Moriya
- Graduate School of Environmental and Life Sciences, Okayama University, Okayama 700-8530, Japan
| |
Collapse
|
24
|
Reith P, Braam S, Welkenhuysen N, Lecinski S, Shepherd J, MacDonald C, Leake MC, Hohmann S, Shashkova S, Cvijovic M. The Effect of Lithium on the Budding Yeast Saccharomyces cerevisiae upon Stress Adaptation. Microorganisms 2022; 10:590. [PMID: 35336166 PMCID: PMC8953283 DOI: 10.3390/microorganisms10030590] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 03/02/2022] [Accepted: 03/07/2022] [Indexed: 02/05/2023] Open
Abstract
Lithium salts are used in the treatment of mood disorders, cancer, and Alzheimer's disease. It has been shown to prolong life span in several phyla; however, not yet in budding yeast. In our study, we investigate the influence of lithium on yeast cells' viability by characterizing protein aggregate formation, cell volume, and molecular crowding in the context of stress adaptation. While our data suggest a concentration-dependent growth inhibition caused by LiCl, we show an extended long-term survival rate as an effect of lithium addition upon glucose deprivation. We show that caloric restriction mitigates the negative impact of LiCl on cellular survival. Therefore, we suggest that lithium could affect glucose metabolism upon caloric restriction, which could explain the extended long-term survival observed in our study. We find furthermore that lithium chloride did not affect an immediate salt-induced Hsp104-dependent aggregate formation but cellular adaptation to H2O2 and acute glucose starvation. We presume that different salt types and concentrations interfere with effective Hsp104 recruitment or its ATP-dependent disaggregase activity as a response to salt stress. This work provides novel details of Li+ effect on live eukaryotic cells which may also be applicable in further research on the treatment of cancer, Alzheimer's, or other age-related diseases in humans.
Collapse
Affiliation(s)
- Patrick Reith
- Department of Mathematical Sciences, University of Gothenburg, 412 96 Gothenburg, Sweden; (P.R.); (S.B.); (N.W.)
- Department of Mathematical Sciences, Chalmers University of Technology, 412 96 Gothenburg, Sweden
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden;
| | - Svenja Braam
- Department of Mathematical Sciences, University of Gothenburg, 412 96 Gothenburg, Sweden; (P.R.); (S.B.); (N.W.)
- Department of Mathematical Sciences, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Niek Welkenhuysen
- Department of Mathematical Sciences, University of Gothenburg, 412 96 Gothenburg, Sweden; (P.R.); (S.B.); (N.W.)
- Department of Mathematical Sciences, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Sarah Lecinski
- Department of Physics, University of York, York YO10 5DD, UK; (S.L.); (J.S.); (M.C.L.)
| | - Jack Shepherd
- Department of Physics, University of York, York YO10 5DD, UK; (S.L.); (J.S.); (M.C.L.)
- Department of Biology, University of York, York YO10 5DD, UK;
| | - Chris MacDonald
- Department of Biology, University of York, York YO10 5DD, UK;
| | - Mark C. Leake
- Department of Physics, University of York, York YO10 5DD, UK; (S.L.); (J.S.); (M.C.L.)
- Department of Biology, University of York, York YO10 5DD, UK;
| | - Stefan Hohmann
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden;
| | - Sviatlana Shashkova
- Department of Mathematical Sciences, University of Gothenburg, 412 96 Gothenburg, Sweden; (P.R.); (S.B.); (N.W.)
- Department of Mathematical Sciences, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Marija Cvijovic
- Department of Mathematical Sciences, University of Gothenburg, 412 96 Gothenburg, Sweden; (P.R.); (S.B.); (N.W.)
- Department of Mathematical Sciences, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| |
Collapse
|
25
|
Bunk D, Moriasy J, Thoma F, Jakubke C, Osman C, Hörl D. YeastMate: Neural network-assisted segmentation of mating and budding events in S. cerevisiae. Bioinformatics 2022; 38:2667-2669. [PMID: 35179572 PMCID: PMC9048668 DOI: 10.1093/bioinformatics/btac107] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 01/14/2022] [Accepted: 02/16/2022] [Indexed: 11/14/2022] Open
Abstract
SUMMARY Here, we introduce YeastMate, a user-friendly deep learning-based application for automated detection and segmentation of Saccharomyces cerevisiae cells and their mating and budding events in microscopy images. We build upon Mask R-CNN with a custom segmentation head for the subclassification of mother and daughter cells during lifecycle transitions. YeastMate can be used directly as a Python library or through a stand-alone GUI application and a Fiji plugin as easy to use frontends. AVAILABILITY AND IMPLEMENTATION The source code for YeastMate is freely available at https://github.com/hoerlteam/YeastMate under the MIT license. We offer installers for our software stack for Windows, macOS and Linux. A detailed user guide is available at https://yeastmate.readthedocs.io. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
Collapse
Affiliation(s)
- David Bunk
- Faculty of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - Julian Moriasy
- Faculty of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - Felix Thoma
- Faculty of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - Christopher Jakubke
- Faculty of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - Christof Osman
- Faculty of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - David Hörl
- Faculty of Biology, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| |
Collapse
|
26
|
Kruitbosch HT, Mzayek Y, Omlor S, Guerra P, Milias-Argeitis A. A convolutional neural network for segmentation of yeast cells without manual training annotations. Bioinformatics 2022; 38:1427-1433. [PMID: 34893817 PMCID: PMC8825468 DOI: 10.1093/bioinformatics/btab835] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 10/09/2021] [Accepted: 12/07/2021] [Indexed: 01/05/2023] Open
Abstract
MOTIVATION Single-cell time-lapse microscopy is a ubiquitous tool for studying the dynamics of complex cellular processes. While imaging can be automated to generate very large volumes of data, the processing of the resulting movies to extract high-quality single-cell information remains a challenging task. The development of software tools that automatically identify and track cells is essential for realizing the full potential of time-lapse microscopy data. Convolutional neural networks (CNNs) are ideally suited for such applications, but require great amounts of manually annotated data for training, a time-consuming and tedious process. RESULTS We developed a new approach to CNN training for yeast cell segmentation based on synthetic data and present (i) a software tool for the generation of synthetic images mimicking brightfield images of budding yeast cells and (ii) a convolutional neural network (Mask R-CNN) for yeast segmentation that was trained on a fully synthetic dataset. The Mask R-CNN performed excellently on segmenting actual microscopy images of budding yeast cells, and a density-based spatial clustering algorithm (DBSCAN) was able to track the detected cells across the frames of microscopy movies. Our synthetic data creation tool completely bypassed the laborious generation of manually annotated training datasets, and can be easily adjusted to produce images with many different features. The incorporation of synthetic data creation into the development pipeline of CNN-based tools for budding yeast microscopy is a critical step toward the generation of more powerful, widely applicable and user-friendly image processing tools for this microorganism. AVAILABILITY AND IMPLEMENTATION The synthetic data generation code can be found at https://github.com/prhbrt/synthetic-yeast-cells. The Mask R-CNN as well as the tuning and benchmarking scripts can be found at https://github.com/ymzayek/yeastcells-detection-maskrcnn. We also provide Google Colab scripts that reproduce all the results of this work. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
Collapse
Affiliation(s)
- Herbert T Kruitbosch
- Center for Information Technology, University of Groningen, 9747 AJ Groningen, The Netherlands
| | - Yasmin Mzayek
- Center for Information Technology, University of Groningen, 9747 AJ Groningen, The Netherlands
| | - Sara Omlor
- Center for Information Technology, University of Groningen, 9747 AJ Groningen, The Netherlands
| | - Paolo Guerra
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Andreas Milias-Argeitis
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, The Netherlands
| |
Collapse
|
27
|
Parvizi Omran R, Ramírez-Zavala B, Aji Tebung W, Yao S, Feng J, Law C, Dumeaux V, Morschhäuser J, Whiteway M. The zinc cluster transcription factor Rha1 is a positive filamentation regulator in Candida albicans. Genetics 2022; 220:iyab155. [PMID: 34849863 PMCID: PMC8733637 DOI: 10.1093/genetics/iyab155] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 09/10/2021] [Indexed: 01/31/2023] Open
Abstract
Zinc cluster transcription factors (TFs) are essential fungal regulators of gene expression. In the pathogen Candida albicans, the gene orf19.1604 encodes a zinc cluster TF regulating filament development. Hyperactivation of orf19.1604, which we have named RHA1 for Regulator of Hyphal Activity, generates wrinkled colony morphology under nonhyphal growth conditions, triggers filament formation, invasiveness, and enhanced biofilm formation and causes reduced virulence in the mouse model of systemic infection. The strain expressing activated Rha1 shows up-regulation of genes required for filamentation and cell-wall-adhesion-related proteins. Increased expression is also seen for the hyphal-inducing TFs Brg1 and Ume6, while the hyphal repressor Nrg1 is downregulated. Inactivation of RHA1 reduces filamentation under a variety of filament-inducing conditions. In contrast to the partial effect of either single mutant, the double rha1 ume6 mutant strain is highly defective in both serum- and Spider-medium-stimulated hyphal development. While the loss of Brg1 function blocks serum-stimulated hyphal development, this block can be significantly bypassed by Rha1 hyperactivity, and the combination of Rha1 hyperactivity and serum addition can generate significant polarization even in brg1 ume6 double mutants. Thus, in response to external signals, Rha1 functions with other morphogenesis regulators including Brg1 and Ume6, to mediate filamentation.
Collapse
Affiliation(s)
- Raha Parvizi Omran
- Department of Biology, Concordia University, Montreal, QC H4B 1R6, Canada
| | | | - Walters Aji Tebung
- The George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
| | - Shuangyan Yao
- Department of Pathogen Biology, School of Medicine, Nantong University, Nantong 226001, China
| | - Jinrong Feng
- Department of Pathogen Biology, School of Medicine, Nantong University, Nantong 226001, China
| | - Chris Law
- Centre for Microscopy and Cellular Imaging, Concordia University, Montreal, QC H4B 1R6, Canada
| | - Vanessa Dumeaux
- Department of Biology, Concordia University, Montreal, QC H4B 1R6, Canada
- PERFORM Centre, Concordia University, Montreal, QC H4B 1R6, Canada
| | - Joachim Morschhäuser
- Institut für Molekulare Infektionsbiologie, Universität Würzburg, Würzburg, Germany
| | - Malcolm Whiteway
- Department of Biology, Concordia University, Montreal, QC H4B 1R6, Canada
| |
Collapse
|
28
|
Lecinski S, Shepherd JW, Frame L, Hayton I, MacDonald C, Leake MC. Investigating molecular crowding during cell division and hyperosmotic stress in budding yeast with FRET. CURRENT TOPICS IN MEMBRANES 2021; 88:75-118. [PMID: 34862033 PMCID: PMC7612257 DOI: 10.1016/bs.ctm.2021.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Cell division, aging, and stress recovery triggers spatial reorganization of cellular components in the cytoplasm, including membrane bound organelles, with molecular changes in their compositions and structures. However, it is not clear how these events are coordinated and how they integrate with regulation of molecular crowding. We use the budding yeast Saccharomyces cerevisiae as a model system to study these questions using recent progress in optical fluorescence microscopy and crowding sensing probe technology. We used a Förster Resonance Energy Transfer (FRET) based sensor, illuminated by confocal microscopy for high throughput analyses and Slimfield microscopy for single-molecule resolution, to quantify molecular crowding. We determine crowding in response to cellular growth of both mother and daughter cells, in addition to osmotic stress, and reveal hot spots of crowding across the bud neck in the burgeoning daughter cell. This crowding might be rationalized by the packing of inherited material, like the vacuole, from mother cells. We discuss recent advances in understanding the role of crowding in cellular regulation and key current challenges and conclude by presenting our recent advances in optimizing FRET-based measurements of crowding while simultaneously imaging a third color, which can be used as a marker that labels organelle membranes. Our approaches can be combined with synchronized cell populations to increase experimental throughput and correlate molecular crowding information with different stages in the cell cycle.
Collapse
Affiliation(s)
- Sarah Lecinski
- Department of Physics, University of York, York, United Kingdom
| | - Jack W Shepherd
- Department of Physics, University of York, York, United Kingdom; Department of Biology, University of York, York, United Kingdom
| | - Lewis Frame
- School of Natural Sciences, University of York, York, United Kingdom
| | - Imogen Hayton
- Department of Biology, University of York, York, United Kingdom
| | - Chris MacDonald
- Department of Biology, University of York, York, United Kingdom
| | - Mark C Leake
- Department of Physics, University of York, York, United Kingdom; Department of Biology, University of York, York, United Kingdom.
| |
Collapse
|
29
|
Altered Protein Abundance and Localization Inferred from Sites of Alternative Modification by Ubiquitin and SUMO. J Mol Biol 2021; 433:167219. [PMID: 34464654 DOI: 10.1016/j.jmb.2021.167219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 08/11/2021] [Accepted: 08/23/2021] [Indexed: 12/19/2022]
Abstract
Protein modification by ubiquitin or SUMO can alter the function, stability or activity of target proteins. Previous studies have identified thousands of substrates that were modified by ubiquitin or SUMO on the same lysine residue. However, it remains unclear whether such overlap could result from a mere higher solvent accessibility, whether proteins containing those sites are associated with specific functional traits, and whether selectively perturbing their modification by ubiquitin or SUMO could result in different phenotypic outcomes. Here, we mapped reported lysine modification sites across the human proteome and found an enrichment of sites reported to be modified by both ubiquitin and SUMO. Our analysis uncovered thousands of proteins containing such sites, which we term Sites of Alternative Modification (SAMs). Among more than 36,000 sites reported to be modified by SUMO, 51.8% have also been reported to be modified by ubiquitin. SAM-containing proteins are associated with diverse biological functions including cell cycle, DNA damage, and transcriptional regulation. As such, our analysis highlights numerous proteins and pathways as putative targets for further elucidating the crosstalk between ubiquitin and SUMO. Comparing the biological and biochemical properties of SAMs versus other non-overlapping modification sites revealed that these sites were associated with altered cellular localization or abundance of their host proteins. Lastly, using S. cerevisiae as model, we show that mutating the SAM motif in a protein can influence its ubiquitination as well as its localization and abundance.
Collapse
|
30
|
Yeast cell segmentation in microstructured environments with deep learning. Biosystems 2021; 211:104557. [PMID: 34634444 DOI: 10.1016/j.biosystems.2021.104557] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 09/09/2021] [Accepted: 09/30/2021] [Indexed: 11/23/2022]
Abstract
Cell segmentation is a major bottleneck in extracting quantitative single-cell information from microscopy data. The challenge is exasperated in the setting of microstructured environments. While deep learning approaches have proven useful for general cell segmentation tasks, previously available segmentation tools for the yeast-microstructure setting rely on traditional machine learning approaches. Here we present convolutional neural networks trained for multiclass segmenting of individual yeast cells and discerning these from cell-similar microstructures. An U-Net based semantic segmentaiton approach, as well as a direct instance segmentation approach with a Mask R-CNN are demonstrated. We give an overview of the datasets recorded for training, validating and testing the networks, as well as a typical use-case. We showcase the methods' contribution to segmenting yeast in microstructured environments with a typical systems or synthetic biology application. The models achieve robust segmentation results, outperforming the previous state-of-the-art in both accuracy and speed. The combination of fast and accurate segmentation is not only beneficial for a posteriori data processing, it also makes online monitoring of thousands of trapped cells or closed-loop optimal experimental design feasible from an image processing perspective. Code is and data samples are available at https://git.rwth-aachen.de/bcs/projects/tp/multiclass-yeast-seg.
Collapse
|
31
|
Hsu IS, Strome B, Lash E, Robbins N, Cowen LE, Moses AM. A functionally divergent intrinsically disordered region underlying the conservation of stochastic signaling. PLoS Genet 2021; 17:e1009629. [PMID: 34506483 PMCID: PMC8457507 DOI: 10.1371/journal.pgen.1009629] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 09/22/2021] [Accepted: 08/06/2021] [Indexed: 12/18/2022] Open
Abstract
Stochastic signaling dynamics expand living cells' information processing capabilities. An increasing number of studies report that regulators encode information in their pulsatile dynamics. The evolutionary mechanisms that lead to complex signaling dynamics remain uncharacterized, perhaps because key interactions of signaling proteins are encoded in intrinsically disordered regions (IDRs), whose evolution is difficult to analyze. Here we focused on the IDR that controls the stochastic pulsing dynamics of Crz1, a transcription factor in fungi downstream of the widely conserved calcium signaling pathway. We find that Crz1 IDRs from anciently diverged fungi can all respond transiently to calcium stress; however, only Crz1 IDRs from the Saccharomyces clade support pulsatility, encode extra information, and rescue fitness in competition assays, while the Crz1 IDRs from distantly related fungi do none of the three. On the other hand, we find that Crz1 pulsing is conserved in the distantly related fungi, consistent with the evolutionary model of stabilizing selection on the signaling phenotype. Further, we show that a calcineurin docking site in a specific part of the IDRs appears to be sufficient for pulsing and show evidence for a beneficial increase in the relative calcineurin affinity of this docking site. We propose that evolutionary flexibility of functionally divergent IDRs underlies the conservation of stochastic signaling by stabilizing selection.
Collapse
Affiliation(s)
- Ian S. Hsu
- Department of Cell & Systems Biology, University of Toronto, Toronto, Canada
| | - Bob Strome
- Department of Cell & Systems Biology, University of Toronto, Toronto, Canada
| | - Emma Lash
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Leah E. Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Alan M. Moses
- Department of Cell & Systems Biology, University of Toronto, Toronto, Canada
- Department of Computer Science, University of Toronto, Toronto, Canada
- * E-mail:
| |
Collapse
|
32
|
Fry MY, Saladi SM, Cunha A, Clemons WM. Sequence-based features that are determinant for tail-anchored membrane protein sorting in eukaryotes. Traffic 2021; 22:306-318. [PMID: 34288289 PMCID: PMC8380732 DOI: 10.1111/tra.12809] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 07/15/2021] [Accepted: 07/18/2021] [Indexed: 11/29/2022]
Abstract
The correct targeting and insertion of tail-anchored (TA) integral membrane proteins is critical for cellular homeostasis. TA proteins are defined by a hydrophobic transmembrane domain (TMD) at their C-terminus and are targeted to either the ER or mitochondria. Derived from experimental measurements of a few TA proteins, there has been little examination of the TMD features that determine localization. As a result, the localization of many TA proteins are misclassified by the simple heuristic of overall hydrophobicity. Because ER-directed TMDs favor arrangement of hydrophobic residues to one side, we sought to explore the role of geometric hydrophobic properties. By curating TA proteins with experimentally determined localizations and assessing hypotheses for recognition, we bioinformatically and experimentally verify that a hydrophobic face is the most accurate singular metric for separating ER and mitochondria-destined yeast TA proteins. A metric focusing on an 11 residue segment of the TMD performs well when classifying human TA proteins. The most inclusive predictor uses both hydrophobicity and C-terminal charge in tandem. This work provides context for previous observations and opens the door for more detailed mechanistic experiments to determine the molecular factors driving this recognition.
Collapse
Affiliation(s)
- Michelle Y. Fry
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, USA
| | - Shyam M. Saladi
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, USA
| | - Alexandre Cunha
- Division of Biology and Biological Engineering, Center for Advanced Methods in Biological Image Analysis, Beckman Institute, Pasadena, California, USA
| | - William M. Clemons
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, USA
| |
Collapse
|
33
|
Costa ACBP, Omran RP, Law C, Dumeaux V, Whiteway M. Signal-mediated localization of Candida albicans pheromone response pathway components. G3-GENES GENOMES GENETICS 2021; 11:6033596. [PMID: 33793759 PMCID: PMC8022970 DOI: 10.1093/g3journal/jkaa033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 11/25/2020] [Indexed: 01/07/2023]
Abstract
A MAPK cascade consists of three kinases, (MEKK, MEK and MAPK), that are sequentially activated in response to a stimulus and serve to transmit signals. In C. albicans and in yeast, an MAPK cascade is linked to the pheromone pathway through a scaffold protein (Cst5 and Ste5, respectively). Cst5 is much shorter and lacks key domains compared to Ste5, so in C. albicans, other elements, in particular the MEKK Ste11, play key roles in controlling the associations and localizations of network components. Abstract Candida albicans opaque cells release pheromones to stimulate cells of opposite mating type to activate their pheromone response pathway. Although this fungal pathogen shares orthologous proteins involved in the process with Saccharomyces cerevisiae, the pathway in each organism has unique characteristics. We have used GFP-tagged fusion proteins to investigate the localization of the scaffold protein Cst5, as well as the MAP kinases Cek1 and Cek2, during pheromone response in C. albicans. In wild-type cells, pheromone treatment directed Cst5-GFP to surface puncta concentrated at the tips of mating projections. These puncta failed to form in cells defective in either the Gα or β subunits. However, they still formed in response to pheromone in cells missing Ste11, but with the puncta distributed around the cell periphery in the absence of mating projections. These puncta were absent from hst7Δ/Δ cells, but could be detected in the ste11Δ/Δ hst7Δ/Δ double mutant. Cek2-GFP showed a strong nuclear localization late in the response, consistent with a role in adaptation, while Cek1-GFP showed a weaker, but early increase in nuclear localization after pheromone treatment. Activation loop phosphorylation of both Cek1 and Cek2 required the presence of Ste11. In contrast to Cek2-GFP, which showed no localization signal in ste11Δ/Δ cells, Cek1-GFP showed enhanced nuclear localization that was pheromone independent in the ste11Δ/Δ mutant. The results are consistent with CaSte11 facilitating Hst7-mediated MAP kinase phosphorylation and also playing a potentially critical role in both MAP kinase and Cst5 scaffold localization.
Collapse
Affiliation(s)
| | - Raha Parvizi Omran
- Department of Biology, Concordia University, Montreal, QC H4B 1R6, Canada
| | - Chris Law
- Centre for Microscopy and Cellular Imaging, Concordia University, Montreal, QC H4B 1R6, Canada
| | - Vanessa Dumeaux
- PERFORM Centre, Concordia University, Montreal, QC H4B 1R6, Canada
| | - Malcolm Whiteway
- Department of Biology, Concordia University, Montreal, QC H4B 1R6, Canada
| |
Collapse
|
34
|
Robert M, Waldhauer J, Stritt F, Yang B, Pauly M, Voiniciuc C. Modular biosynthesis of plant hemicellulose and its impact on yeast cells. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:140. [PMID: 34147122 PMCID: PMC8214268 DOI: 10.1186/s13068-021-01985-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 06/04/2021] [Indexed: 05/25/2023]
Abstract
BACKGROUND The carbohydrate polymers that encapsulate plants cells have benefited humans for centuries and have valuable biotechnological uses. In the past 5 years, exciting possibilities have emerged in the engineering of polysaccharide-based biomaterials. Despite impressive advances on bacterial cellulose-based hydrogels, comparatively little is known about how plant hemicelluloses can be reconstituted and modulated in cells suitable for biotechnological purposes. RESULTS Here, we assembled cellulose synthase-like A (CSLA) enzymes using an optimized Pichia pastoris platform to produce tunable heteromannan (HM) polysaccharides in yeast. By swapping the domains of plant mannan and glucomannan synthases, we engineered chimeric CSLA proteins that made β-1,4-linked mannan in quantities surpassing those of the native enzymes while minimizing the burden on yeast growth. Prolonged expression of a glucomannan synthase from Amorphophallus konjac was toxic to yeast cells: reducing biomass accumulation and ultimately leading to compromised cell viability. However, an engineered glucomannan synthase as well as CSLA pure mannan synthases and a CSLC glucan synthase did not inhibit growth. Interestingly, Pichia cell size could be increased or decreased depending on the composition of the CSLA protein sequence. HM yield and glucose incorporation could be further increased by co-expressing chimeric CSLA proteins with a MANNAN-SYNTHESIS-RELATED (MSR) co-factor from Arabidopsis thaliana. CONCLUSION The results provide novel routes for the engineering of polysaccharide-based biomaterials that are needed for a sustainable bioeconomy. The characterization of chimeric cellulose synthase-like enzymes in yeast offers an exciting avenue to produce plant polysaccharides in a tunable manner. Furthermore, cells modified with non-toxic plant polysaccharides such as β-mannan offer a modular chassis to produce and encapsulate sensitive cargo such as therapeutic proteins.
Collapse
Affiliation(s)
- Madalen Robert
- Independent Junior Research Group - Designer Glycans, Leibniz Institute of Plant Biochemistry, 06120, Halle, Germany
| | - Julian Waldhauer
- Independent Junior Research Group - Designer Glycans, Leibniz Institute of Plant Biochemistry, 06120, Halle, Germany
| | - Fabian Stritt
- Institute for Plant Cell Biology and Biotechnology, Heinrich Heine University, 40225, Düsseldorf, Germany
| | - Bo Yang
- Independent Junior Research Group - Designer Glycans, Leibniz Institute of Plant Biochemistry, 06120, Halle, Germany
| | - Markus Pauly
- Institute for Plant Cell Biology and Biotechnology, Heinrich Heine University, 40225, Düsseldorf, Germany
| | - Cătălin Voiniciuc
- Independent Junior Research Group - Designer Glycans, Leibniz Institute of Plant Biochemistry, 06120, Halle, Germany.
| |
Collapse
|
35
|
YeastNet: Deep-Learning-Enabled Accurate Segmentation of Budding Yeast Cells in Bright-Field Microscopy. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11062692] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Accurate and efficient segmentation of live-cell images is critical in maximizing data extraction and knowledge generation from high-throughput biology experiments. Despite recent development of deep-learning tools for biomedical imaging applications, great demand for automated segmentation tools for high-resolution live-cell microscopy images remains in order to accelerate the analysis. YeastNet dramatically improves the performance of the non-trainable classic algorithm, and performs considerably better than the current state-of-the-art yeast-cell segmentation tools. We have designed and trained a U-Net convolutional network (named YeastNet) to conduct semantic segmentation on bright-field microscopy images and generate segmentation masks for cell labeling and tracking. YeastNet enables accurate automatic segmentation and tracking of yeast cells in biomedical applications. YeastNet is freely provided with model weights as a Python package on GitHub.
Collapse
|
36
|
Farris D, Saxton DS, Rine J. A novel allele of SIR2 reveals a heritable intermediate state of gene silencing. Genetics 2021; 218:6169529. [PMID: 33713126 DOI: 10.1093/genetics/iyab041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 03/08/2021] [Indexed: 12/22/2022] Open
Abstract
Genetic information acquires additional meaning through epigenetic regulation, the process by which genetically identical cells can exhibit heritable differences in gene expression and phenotype. Inheritance of epigenetic information is a critical step in maintaining cellular identity and organismal health. In Saccharomyces cerevisiae, one form of epigenetic regulation is the transcriptional silencing of two mating-type loci, HML and HMR, by the SIR-protein complex. To focus on the epigenetic dimension of this gene regulation, we conducted a forward mutagenesis screen to identify mutants exhibiting an epigenetic or metastable silencing defect. We utilized fluorescent reporters at HML and HMR, and screened yeast colonies for epigenetic silencing defects. We uncovered numerous independent sir1 alleles, a gene known to be required for stable epigenetic inheritance. More interestingly, we recovered a missense mutation within SIR2, which encodes a highly conserved histone deacetylase. In contrast to sir1Δ, which exhibits states that are either fully silenced or fully expressed, this sir2 allele exhibited heritable states that were either fully silenced or expressed at an intermediate level. The heritable nature of this unique silencing defect was influenced by, but not completely dependent on, changes in rDNA copy number. Therefore, this study revealed a heritable state of intermediate silencing and linked this state to a central silencing factor, Sir2.
Collapse
Affiliation(s)
- Delaney Farris
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Daniel S Saxton
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Jasper Rine
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| |
Collapse
|
37
|
Protein context shapes the specificity of SH3 domain-mediated interactions in vivo. Nat Commun 2021; 12:1597. [PMID: 33712617 PMCID: PMC7954794 DOI: 10.1038/s41467-021-21873-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 02/17/2021] [Indexed: 02/07/2023] Open
Abstract
Protein–protein interactions (PPIs) between modular binding domains and their target peptide motifs are thought to largely depend on the intrinsic binding specificities of the domains. The large family of SRC Homology 3 (SH3) domains contribute to cellular processes via their ability to support such PPIs. While the intrinsic binding specificities of SH3 domains have been studied in vitro, whether each domain is necessary and sufficient to define PPI specificity in vivo is largely unknown. Here, by combining deletion, mutation, swapping and shuffling of SH3 domains and measurements of their impact on protein interactions in yeast, we find that most SH3s do not dictate PPI specificity independently from their host protein in vivo. We show that the identity of the host protein and the position of the SH3 domains within their host are critical for PPI specificity, for cellular functions and for key biophysical processes such as phase separation. Our work demonstrates the importance of the interplay between a modular PPI domain such as SH3 and its host protein in establishing specificity to wire PPI networks. These findings will aid understanding how protein networks are rewired during evolution and in the context of mutation-driven diseases such as cancer. The SRC Homology 3 (SH3) domains mediate protein–protein interactions (PPIs). Here, the authors assess the SH3-mediated PPIs in yeast, and show that the identity of the protein itself and the position of the SH3 both affect the interaction specificity and thus the PPI-dependent cellular functions.
Collapse
|
38
|
Waibel DJE, Shetab Boushehri S, Marr C. InstantDL: an easy-to-use deep learning pipeline for image segmentation and classification. BMC Bioinformatics 2021; 22:103. [PMID: 33653266 PMCID: PMC7971147 DOI: 10.1186/s12859-021-04037-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 02/21/2021] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Deep learning contributes to uncovering molecular and cellular processes with highly performant algorithms. Convolutional neural networks have become the state-of-the-art tool to provide accurate and fast image data processing. However, published algorithms mostly solve only one specific problem and they typically require a considerable coding effort and machine learning background for their application. RESULTS We have thus developed InstantDL, a deep learning pipeline for four common image processing tasks: semantic segmentation, instance segmentation, pixel-wise regression and classification. InstantDL enables researchers with a basic computational background to apply debugged and benchmarked state-of-the-art deep learning algorithms to their own data with minimal effort. To make the pipeline robust, we have automated and standardized workflows and extensively tested it in different scenarios. Moreover, it allows assessing the uncertainty of predictions. We have benchmarked InstantDL on seven publicly available datasets achieving competitive performance without any parameter tuning. For customization of the pipeline to specific tasks, all code is easily accessible and well documented. CONCLUSIONS With InstantDL, we hope to empower biomedical researchers to conduct reproducible image processing with a convenient and easy-to-use pipeline.
Collapse
Affiliation(s)
- Dominik Jens Elias Waibel
- Institute of Computational Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
- School of Life Sciences, Technical University of Munich, Weihenstephan, Germany
| | - Sayedali Shetab Boushehri
- Institute of Computational Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
- School of Life Sciences, Technical University of Munich, Weihenstephan, Germany
- Roche Innovation Center Munich, Roche Diagnostics GmbH, Penzberg, Germany
| | - Carsten Marr
- Institute of Computational Biology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany.
| |
Collapse
|
39
|
Wilfling F, Lee CW, Erdmann PS, Zheng Y, Sherpa D, Jentsch S, Pfander B, Schulman BA, Baumeister W. A Selective Autophagy Pathway for Phase-Separated Endocytic Protein Deposits. Mol Cell 2020; 80:764-778.e7. [PMID: 33207182 PMCID: PMC7721475 DOI: 10.1016/j.molcel.2020.10.030] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 09/20/2020] [Accepted: 10/21/2020] [Indexed: 12/14/2022]
Abstract
Autophagy eliminates cytoplasmic content selected by autophagy receptors, which link cargo to the membrane-bound autophagosomal ubiquitin-like protein Atg8/LC3. Here, we report a selective autophagy pathway for protein condensates formed by endocytic proteins in yeast. In this pathway, the endocytic protein Ede1 functions as a selective autophagy receptor. Distinct domains within Ede1 bind Atg8 and mediate phase separation into condensates. Both properties are necessary for an Ede1-dependent autophagy pathway for endocytic proteins, which differs from regular endocytosis and does not involve other known selective autophagy receptors but requires the core autophagy machinery. Cryo-electron tomography of Ede1-containing condensates, at the plasma membrane and in autophagic bodies, shows a phase-separated compartment at the beginning and end of the Ede1-mediated selective autophagy route. Our data suggest a model for autophagic degradation of macromolecular protein complexes by the action of intrinsic autophagy receptors.
Collapse
Affiliation(s)
- Florian Wilfling
- Molecular Cell Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany; Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany; Molecular Machines and Signaling, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
| | - Chia-Wei Lee
- Molecular Cell Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany; Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Philipp S Erdmann
- Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
| | - Yumei Zheng
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA; Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Dawafuti Sherpa
- Molecular Machines and Signaling, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Stefan Jentsch
- Molecular Cell Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Boris Pfander
- DNA Replication and Genome Integrity, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Brenda A Schulman
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA; Molecular Machines and Signaling, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Wolfgang Baumeister
- Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
| |
Collapse
|
40
|
Dietler N, Minder M, Gligorovski V, Economou AM, Joly DAHL, Sadeghi A, Chan CHM, Koziński M, Weigert M, Bitbol AF, Rahi SJ. A convolutional neural network segments yeast microscopy images with high accuracy. Nat Commun 2020; 11:5723. [PMID: 33184262 PMCID: PMC7665014 DOI: 10.1038/s41467-020-19557-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 10/15/2020] [Indexed: 11/14/2022] Open
Abstract
The identification of cell borders ('segmentation') in microscopy images constitutes a bottleneck for large-scale experiments. For the model organism Saccharomyces cerevisiae, current segmentation methods face challenges when cells bud, crowd, or exhibit irregular features. We present a convolutional neural network (CNN) named YeaZ, the underlying training set of high-quality segmented yeast images (>10 000 cells) including mutants, stressed cells, and time courses, as well as a graphical user interface and a web application ( www.quantsysbio.com/data-and-software ) to efficiently employ, test, and expand the system. A key feature is a cell-cell boundary test which avoids the need for fluorescent markers. Our CNN is highly accurate, including for buds, and outperforms existing methods on benchmark images, indicating it transfers well to other conditions. To demonstrate how efficient large-scale image processing uncovers new biology, we analyze the geometries of ≈2200 wild-type and cyclin mutant cells and find that morphogenesis control occurs unexpectedly early and gradually.
Collapse
Affiliation(s)
- Nicola Dietler
- Laboratory of the Physics of Biological Systems, Institute of Physics, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Institute of Bioengineering, School of Life Sciences, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Matthias Minder
- Laboratory of the Physics of Biological Systems, Institute of Physics, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Vojislav Gligorovski
- Laboratory of the Physics of Biological Systems, Institute of Physics, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Augoustina Maria Economou
- Laboratory of the Physics of Biological Systems, Institute of Physics, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Denis Alain Henri Lucien Joly
- Laboratory of the Physics of Biological Systems, Institute of Physics, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Ahmad Sadeghi
- Laboratory of the Physics of Biological Systems, Institute of Physics, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Chun Hei Michael Chan
- Laboratory of the Physics of Biological Systems, Institute of Physics, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Mateusz Koziński
- Computer Vision Laboratory, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Martin Weigert
- Institute of Bioengineering, School of Life Sciences, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Anne-Florence Bitbol
- Institute of Bioengineering, School of Life Sciences, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Sahand Jamal Rahi
- Laboratory of the Physics of Biological Systems, Institute of Physics, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland.
| |
Collapse
|
41
|
Lawrimore J, Doshi A, Walker B, Bloom K. AI-Assisted Forward Modeling of Biological Structures. Front Cell Dev Biol 2019; 7:279. [PMID: 31799251 PMCID: PMC6868055 DOI: 10.3389/fcell.2019.00279] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 10/30/2019] [Indexed: 01/01/2023] Open
Abstract
The rise of machine learning and deep learning technologies have allowed researchers to automate image classification. We describe a method that incorporates automated image classification and principal component analysis to evaluate computational models of biological structures. We use a computational model of the kinetochore to demonstrate our artificial-intelligence (AI)-assisted modeling method. The kinetochore is a large protein complex that connects chromosomes to the mitotic spindle to facilitate proper cell division. The kinetochore can be divided into two regions: the inner kinetochore, including proteins that interact with DNA; and the outer kinetochore, comprised of microtubule-binding proteins. These two kinetochore regions have been shown to have different distributions during metaphase in live budding yeast and therefore act as a test case for our forward modeling technique. We find that a simple convolutional neural net (CNN) can correctly classify fluorescent images of inner and outer kinetochore proteins and show a CNN trained on simulated, fluorescent images can detect difference in experimental images. A polymer model of the ribosomal DNA locus serves as a second test for the method. The nucleolus surrounds the ribosomal DNA locus and appears amorphous in live-cell, fluorescent microscopy experiments in budding yeast, making detection of morphological changes challenging. We show a simple CNN can detect subtle differences in simulated images of the ribosomal DNA locus, demonstrating our CNN-based classification technique can be used on a variety of biological structures.
Collapse
Affiliation(s)
- Josh Lawrimore
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Ayush Doshi
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Benjamin Walker
- Department of Mathematics, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Kerry Bloom
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| |
Collapse
|
42
|
Lu AX, Kraus OZ, Cooper S, Moses AM. Learning unsupervised feature representations for single cell microscopy images with paired cell inpainting. PLoS Comput Biol 2019; 15:e1007348. [PMID: 31479439 PMCID: PMC6743779 DOI: 10.1371/journal.pcbi.1007348] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 09/13/2019] [Accepted: 08/20/2019] [Indexed: 12/03/2022] Open
Abstract
Cellular microscopy images contain rich insights about biology. To extract this information, researchers use features, or measurements of the patterns of interest in the images. Here, we introduce a convolutional neural network (CNN) to automatically design features for fluorescence microscopy. We use a self-supervised method to learn feature representations of single cells in microscopy images without labelled training data. We train CNNs on a simple task that leverages the inherent structure of microscopy images and controls for variation in cell morphology and imaging: given one cell from an image, the CNN is asked to predict the fluorescence pattern in a second different cell from the same image. We show that our method learns high-quality features that describe protein expression patterns in single cells both yeast and human microscopy datasets. Moreover, we demonstrate that our features are useful for exploratory biological analysis, by capturing high-resolution cellular components in a proteome-wide cluster analysis of human proteins, and by quantifying multi-localized proteins and single-cell variability. We believe paired cell inpainting is a generalizable method to obtain feature representations of single cells in multichannel microscopy images. To understand the cell biology captured by microscopy images, researchers use features, or measurements of relevant properties of cells, such as the shape or size of cells, or the intensity of fluorescent markers. Features are the starting point of most image analysis pipelines, so their quality in representing cells is fundamental to the success of an analysis. Classically, researchers have relied on features manually defined by imaging experts. In contrast, deep learning techniques based on convolutional neural networks (CNNs) automatically learn features, which can outperform manually-defined features at image analysis tasks. However, most CNN methods require large manually-annotated training datasets to learn useful features, limiting their practical application. Here, we developed a new CNN method that learns high-quality features for single cells in microscopy images, without the need for any labeled training data. We show that our features surpass other comparable features in identifying protein localization from images, and that our method can generalize to diverse datasets. By exploiting our method, researchers will be able to automatically obtain high-quality features customized to their own image datasets, facilitating many downstream analyses, as we highlight by demonstrating many possible use cases of our features in this study.
Collapse
Affiliation(s)
- Alex X. Lu
- Department of Computer Science, University of Toronto, Toronto, Canada
| | | | | | - Alan M. Moses
- Department of Computer Science, University of Toronto, Toronto, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
- Center for Analysis of Genome Evolution and Function, University of Toronto, Toronto, Canada
- * E-mail:
| |
Collapse
|
43
|
Zarin T, Strome B, Nguyen Ba AN, Alberti S, Forman-Kay JD, Moses AM. Proteome-wide signatures of function in highly diverged intrinsically disordered regions. eLife 2019; 8:e46883. [PMID: 31264965 PMCID: PMC6634968 DOI: 10.7554/elife.46883] [Citation(s) in RCA: 102] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 07/01/2019] [Indexed: 12/24/2022] Open
Abstract
Intrinsically disordered regions make up a large part of the proteome, but the sequence-to-function relationship in these regions is poorly understood, in part because the primary amino acid sequences of these regions are poorly conserved in alignments. Here we use an evolutionary approach to detect molecular features that are preserved in the amino acid sequences of orthologous intrinsically disordered regions. We find that most disordered regions contain multiple molecular features that are preserved, and we define these as 'evolutionary signatures' of disordered regions. We demonstrate that intrinsically disordered regions with similar evolutionary signatures can rescue function in vivo, and that groups of intrinsically disordered regions with similar evolutionary signatures are strongly enriched for functional annotations and phenotypes. We propose that evolutionary signatures can be used to predict function for many disordered regions from their amino acid sequences.
Collapse
Affiliation(s)
- Taraneh Zarin
- Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
| | - Bob Strome
- Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
| | - Alex N Nguyen Ba
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, United States
| | - Simon Alberti
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Center for Molecular and Cellular Bioengineering, Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - Julie D Forman-Kay
- Program in Molecular Medicine, Hospital for Sick Children, Toronto, Canada
- Department of Biochemistry, University of Toronto, Toronto, Canada
| | - Alan M Moses
- Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
- Department of Computer Science, University of Toronto, Toronto, Canada
| |
Collapse
|