scholarly journals Reconstructing regulatory pathways by systematically mapping protein localization interdependency networks

2017 ◽  
Author(s):  
James Dodgson ◽  
Anatole Chessel ◽  
Federico Vaggi ◽  
Marco Giordan ◽  
Miki Yamamoto ◽  
...  

ABSTRACTA key goal of functional genomics is to elucidate how genes and proteins act together in space and time, wired as pathways, to control specific aspects of cell biological function. Here, we develop a method to quantitatively determine proteins’ localization interdependencies at high throughput. We show that this method can be used to systematically obtain weighted, signed and directional pathway relationships, and hence to reconstruct a detailed pathway wiring. As proof-of-principle, we focus on 42 factors that control cell polarity in fission yeast (Schizosaccharomyces pombe) and use high-throughput confocal microscopy and quantitative image analysis to reconstruct their Localization Interdependency Network (LIN). Through this approach we identify 554 pairwise interactions across the factors, including 98% putative new directed links. Validation of an unexpected interaction between two polarity factor subgroups - the polarity landmark proteins and the cell integrity pathway components - by orthogonal phenotyping demonstrates the power of the LIN approach in detecting subtle, systems-level causal connections.


Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 264
Author(s):  
Kaisa Liimatainen ◽  
Riku Huttunen ◽  
Leena Latonen ◽  
Pekka Ruusuvuori

Identifying localization of proteins and their specific subpopulations associated with certain cellular compartments is crucial for understanding protein function and interactions with other macromolecules. Fluorescence microscopy is a powerful method to assess protein localizations, with increasing demand of automated high throughput analysis methods to supplement the technical advancements in high throughput imaging. Here, we study the applicability of deep neural network-based artificial intelligence in classification of protein localization in 13 cellular subcompartments. We use deep learning-based on convolutional neural network and fully convolutional network with similar architectures for the classification task, aiming at achieving accurate classification, but importantly, also comparison of the networks. Our results show that both types of convolutional neural networks perform well in protein localization classification tasks for major cellular organelles. Yet, in this study, the fully convolutional network outperforms the convolutional neural network in classification of images with multiple simultaneous protein localizations. We find that the fully convolutional network, using output visualizing the identified localizations, is a very useful tool for systematic protein localization assessment.



2018 ◽  
Vol 115 (45) ◽  
pp. E10712-E10719 ◽  
Author(s):  
Reed Pifer ◽  
Regan M. Russell ◽  
Aman Kumar ◽  
Meredith M. Curtis ◽  
Vanessa Sperandio

The gut metabolic landscape is complex and is influenced by the microbiota, host physiology, and enteric pathogens. Pathogens have to exquisitely monitor the biogeography of the gastrointestinal tract to find a suitable niche for colonization. To dissect the important metabolic pathways that influence virulence of enterohemorrhagicEscherichia coli(EHEC), we conducted a high-throughput screen. We generated a dataset of regulatory pathways that control EHEC virulence expression under anaerobic conditions. This unraveled that the cysteine-responsive regulator, CutR, converges with the YhaO serine import pump and the fatty acid metabolism regulator FadR to optimally control virulence expression in EHEC. CutR activates expression of YhaO to increase activity of the YhaJ transcription factor that has been previously shown to directly activate the EHEC virulence genes. CutR enhances FadL, which is a pump for fatty acids that represses inhibition of virulence expression by FadR, unmasking a feedback mechanism responsive to metabolite fluctuations. Moreover, CutR and FadR also augment murine infection byCitrobacter rodentium, which is a murine pathogen extensively employed as a surrogate animal model for EHEC. This high-throughput approach proved to be a powerful tool to map the web of cellular circuits that allows an enteric pathogen to monitor the gut environment and adjust the levels of expression of its virulence repertoire toward successful infection of the host.



1990 ◽  
Vol 10 (9) ◽  
pp. 4612-4622
Author(s):  
P J Beck ◽  
P Orlean ◽  
C Albright ◽  
P W Robbins ◽  
M J Gething ◽  
...  

The Saccharomyces cerevisiae DPM1 gene product, dolichol-phosphate-mannose (Dol-P-Man) synthase, is involved in the coupled processes of synthesis and membrane translocation of Dol-P-Man. Dol-P-Man is the lipid-linked sugar donor of the last four mannose residues that are added to the core oligosaccharide transferred to protein during N-linked glycosylation in the endoplasmic reticulum. We present evidence that the S. cerevisiae gene DPM1, when stably transfected into a mutant Chinese hamster ovary cell line, B4-2-1, is able to correct the glycosylation defect of the cells. Evidence for complementation includes (i) fluorescence-activated cell sorter analysis of differential lectin binding to cell surface glycoproteins, (ii) restoration of Dol-P-Man synthase enzymatic activity in crude cell lysates, (iii) isolation and high-performance liquid chromatography fractionation of the lipid-linked oligosaccharides synthesized in the transfected and control cell lines, and (iv) the restoration of endoglycosidase H sensitivity to the oligosaccharides transferred to a specific glycoprotein synthesized in the DPM1 CHO transfectants. Indirect immunofluorescence with a primary antibody directed against the DPM1 protein shows a reticular staining pattern of protein localization in transfected hamster and monkey cell lines.



2013 ◽  
Vol 81 (9) ◽  
pp. 3068-3076 ◽  
Author(s):  
Carolyn R. Morris ◽  
Christen L. Grassel ◽  
Julia C. Redman ◽  
Jason W. Sahl ◽  
Eileen M. Barry ◽  
...  

ABSTRACTShigellaspecies Gram-negative bacteria which cause a diarrheal disease, known as shigellosis, by invading and destroying the colonic mucosa and inducing a robust inflammatory response. With no vaccine available, shigellosis annually kills over 600,000 children in developing countries. This study demonstrates the utility of combining high-throughput bioinformatic methods within vitroandin vivoassays to provide new insights into pathogenesis. Comparisons ofin vivoandin vitrogene expression identified genes associated with intracellular growth. Additional bioinformatics analyses identified genes that are present inS. flexneriisolates but not in the three otherShigellaspecies. Comparison of these two analyses revealed nine genes that are differentially expressed during invasion and that are specific toS. flexneri. One gene, a DeoR family transcriptional regulator with decreased expression during invasion, was further characterized and is now designatedicgR, forintracellulargrowthregulator. Deletion oficgRcaused no difference in growthin vitrobut resulted in increased intracellular replication in HCT-8 cells. Furtherin vitroandin vivostudies using high-throughput sequencing of RNA transcripts (RNA-seq) of an isogenic ΔicgRmutant identified 34 genes that were upregulated under both growth conditions. This combined informatics and functional approach has allowed the characterization of a gene and pathway previously unknown inShigellapathogenesis and provides a framework for further identification of novel virulence factors and regulatory pathways.



2005 ◽  
Vol 33 (6) ◽  
pp. 1407-1408 ◽  
Author(s):  
Y.-H. Hu ◽  
D. Vanhecke ◽  
H. Lehrach ◽  
M. Janitz

Accomplishment of the human and mouse genome projects resulted in accumulation of extensive gene sequence information. However, the information about the biological functions of the identified genes remains a bottleneck of the post-genomic era. Hence, assays providing simple functional information, such as localization of the protein within the cell, can be very helpful in the elucidation of its function. Transfected cell arrays offer a robust platform for protein localization studies. Open reading frames of unknown genes can be linked to a His6-tag or GFP (green fluorescent protein) reporter in expression vectors and subsequently transfected using the cell array. Cellular localization of the transfected proteins is detected either by specific anti-His-tag antibodies or directly by fluorescence of the GFP fusion protein and by counterstaining with organelle-specific dyes. The high throughput of the method in terms of information provided for every single experiment makes this approach superior to classical immunohistological methods for protein localization.



2009 ◽  
Vol 15 (1) ◽  
pp. 21-29 ◽  
Author(s):  
Johanna S. Blees ◽  
Tobias Schmid ◽  
Cheryl L. Thomas ◽  
Alyson R. Baker ◽  
Lauren Benson ◽  
...  

The novel tumor suppressor Pdcd4 affects tumorigenesis by inhibiting translation. Pdcd4 is phosphorylated and subsequently lost by proteasomal degradation in response to tumor-promoting conditions. Here, the authors describe the development of a reporter cell system to monitor the stability of Pdcd4. The phosphorylation-dependent degradation domain (“target”) or an adjacent (“off-target”) region of Pdcd4 was cloned into a luciferase expression system. The target constructs were responsive to Pdcd4 degrading conditions (e.g., TPA, p70S6K1 overactivation), whereas the off-target constructs remained stable. The system was optimized for and shown to be reliable in a high-throughput compatible 384-well format. Screening of 15,275 pure compounds resulted in a hit rate of 0.30% (>" xbd="1092" xhg="1069" ybd="1185" yhg="1147"/>50% inhibition of TPA-induced loss of signal, confirmed by reassay). Among the hits were inhibitors of previously identified critical signaling events for TPA-induced Pdcd4 degradation. One compound was identified to be nonspecific using the off-target control cell line. Screening of 135,678 natural product extracts yielded 42 confirmed, specific hits. Z′ averaged 0.58 across 446 plates. Further characterization of active natural products and synthetic compounds is expected to identify novel Pdcd4 stabilizers that may be useful in targeting translation to prevent or treat cancers. (Journal of Biomolecular Screening 2010:21-29)



2005 ◽  
Vol 33 (6) ◽  
pp. 1407 ◽  
Author(s):  
D. Vanhecke ◽  
Y.-H. Hu ◽  
H. Lehrach ◽  
M. Janitz


2022 ◽  
Author(s):  
Gouri Priya Ranjith ◽  
Jisha Satheesan ◽  
K K Sabu

Abstract Centella asiatica is a widely spread herb mostly found in the tropics having extensive medicinal values. Here, we report for the first time, transcriptome-wide characterization of miRNA profile from the leaves of C. asiatica using high-throughput Illumina sequencing. We identified 227 conserved and 109 putative novel miRNAs. Computational screening revealed potential mRNA targets for both the conserved and novel miRNAs encoding diverse transcription factors and enzymes involved in plant development, disease resistance, metabolic and signaling pathways. Gene ontology annotation and KEGG analysis revealed the miRNA targets to be involved in a wide range of metabolomic and regulatory pathways. The differential expression of the miRNA encoding genes in diverse tissues was determined by real-time PCR analysis. We also found that gene expression levels of miR156, 159 and 1171 was reduced in salicylic acid treated axenic shoot cultures of C. asiatica compared to its control. Furthermore, RLM-RACE experiments mapped miRNA-mediated cleavage at two of the mRNA targets. The present study represents the large-scale identification of microRNAs from C. asiatica and contributes to the base for the up-coming studies on miRNA-mediated gene regulation of plant secondary metabolite pathways in particular.



2021 ◽  
Author(s):  
Jaya Rammohan ◽  
Nina Alperovich ◽  
Bin Shao ◽  
David Ross

RNA degradation plays a major role in cellular function, but current methods for measuring RNA degradation require RNA purification or are low throughput. Here we show how a flow-FISH assay can be used for high-throughput, in situ measurement of RNA degradation without RNA purification. We demonstrate how this approach can be used to simultaneously measure RNA degradation rates of different RNA sequences in a single assay and explore how the assay can be used to examine the effect of cellular context on RNA degradation rates. This assay will be generally useful to quantitatively measure how natural and engineered biological function depends on RNA half-life.



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