651
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Exploring Potential Signals of Selection for Disordered Residues in Prokaryotic and Eukaryotic Proteins. GENOMICS PROTEOMICS & BIOINFORMATICS 2020; 18:549-564. [PMID: 33346088 PMCID: PMC8377245 DOI: 10.1016/j.gpb.2020.06.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 03/29/2020] [Accepted: 06/10/2020] [Indexed: 11/22/2022]
Abstract
Intrinsically disordered proteins (IDPs) are an important class of proteins in all domains of life for their functional importance. However, how nature has shaped the disorder potential of prokaryotic and eukaryotic proteins is still not clearly known. Randomly generated sequences are free of any selective constraints, thus these sequences are commonly used as null models. Considering different types of random protein models, here we seek to understand how the disorder potential of natural eukaryotic and prokaryotic proteins differs from random sequences. Comparing proteome-wide disorder content between real and random sequences of 12 model organisms, we noticed that eukaryotic proteins are enriched in disordered regions compared to random sequences, but in prokaryotes such regions are depleted. By analyzing the position-wise disorder profile, we show that there is a generally higher disorder near the N- and C-terminal regions of eukaryotic proteins as compared to the random models; however, either no or a weak such trend was found in prokaryotic proteins. Moreover, here we show that this preference is not caused by the amino acid or nucleotide composition at the respective sites. Instead, these regions were found to be endowed with a higher fraction of protein–protein binding sites, suggesting their functional importance. We discuss several possible explanations for this pattern, such as improving the efficiency of protein–protein interaction, ribosome movement during translation, and post-translational modification. However, further studies are needed to clearly understand the biophysical mechanisms causing the trend.
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652
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Necci M, Piovesan D, Clementel D, Dosztányi Z, Tosatto SCE. MobiDB-lite 3.0: fast consensus annotation of intrinsic disorder flavours in proteins. Bioinformatics 2020; 36:5533-5534. [PMID: 33325498 DOI: 10.1093/bioinformatics/btaa1045] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 11/03/2020] [Accepted: 12/07/2020] [Indexed: 12/31/2022] Open
Abstract
MOTIVATION The earlier version of MobiDB-lite is currently used in large-scale proteome annotation platforms to detect intrinsic disorder. However, new theoretical models allow for the classification of intrinsically disordered regions into subtypes from sequence features associated with specific polymeric properties or compositional bias. RESULTS MobiDB-lite 3.0 maintains its previous speed and performance but also provides a finer classification of disorder by identifying regions with characteristics of polyolyampholytes, positive or negative polyelectrolytes, low complexity regions or enriched in cysteine, proline or glycine or polar residues. Sub-regions are abundantly detected in IDRs of the human proteome. The new version of MobiDB-lite represents a new step for the proteome level analysis of protein disorder. AVAILABILITY Both the MobiDB-lite 3.0 source code and a docker container are available from the GitHub repository: https://github.com/BioComputingUP/MobiDB-lite.
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Affiliation(s)
- Marco Necci
- Department of Biomedical Sciences, University of Padua, via U. Bassi 58/b, 35121 Padova, Italy
| | - Damiano Piovesan
- Department of Biomedical Sciences, University of Padua, via U. Bassi 58/b, 35121 Padova, Italy
| | - Damiano Clementel
- Department of Biomedical Sciences, University of Padua, via U. Bassi 58/b, 35121 Padova, Italy
| | - Zsuzsanna Dosztányi
- MTA-ELTE Lendület Bioinformatics Research Group, Department of Biochemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/c, Budapest, Hungary
| | - Silvio C E Tosatto
- Department of Biomedical Sciences, University of Padua, via U. Bassi 58/b, 35121 Padova, Italy
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653
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Yu EY, Zahid SS, Ganduri S, Sutherland JH, Hsu M, Holloman WK, Lue NF. Structurally distinct telomere-binding proteins in Ustilago maydis execute non-overlapping functions in telomere replication, recombination, and protection. Commun Biol 2020; 3:777. [PMID: 33328546 PMCID: PMC7744550 DOI: 10.1038/s42003-020-01505-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 11/20/2020] [Indexed: 11/09/2022] Open
Abstract
Duplex telomere binding proteins exhibit considerable structural and functional diversity in fungi. Herein we interrogate the activities and functions of two Myb-containing, duplex telomere repeat-binding factors in Ustilago maydis, a basidiomycete that is evolutionarily distant from the standard fungi. These two telomere-binding proteins, UmTay1 and UmTrf2, despite having distinct domain structures, exhibit comparable affinities and sequence specificity for the canonical telomere repeats. UmTay1 specializes in promoting telomere replication and an ALT-like pathway, most likely by modulating the helicase activity of Blm. UmTrf2, in contrast, is critical for telomere protection; transcriptional repression of Umtrf2 leads to severe growth defects and profound telomere aberrations. Comparative analysis of UmTay1 homologs in different phyla reveals broad functional diversity for this protein family and provides a case study for how DNA-binding proteins can acquire and lose functions at various chromosomal locations. Our findings also point to stimulatory effect of telomere protein on ALT in Ustilago maydis that may be conserved in other systems.
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Affiliation(s)
- Eun Young Yu
- Department of Microbiology & Immunology, W. R. Hearst Microbiology Research Center, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Syed S Zahid
- Department of Microbiology & Immunology, W. R. Hearst Microbiology Research Center, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Swapna Ganduri
- Department of Microbiology & Immunology, W. R. Hearst Microbiology Research Center, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Jeanette H Sutherland
- Department of Microbiology & Immunology, W. R. Hearst Microbiology Research Center, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Min Hsu
- Department of Microbiology & Immunology, W. R. Hearst Microbiology Research Center, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - William K Holloman
- Department of Microbiology & Immunology, W. R. Hearst Microbiology Research Center, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Neal F Lue
- Department of Microbiology & Immunology, W. R. Hearst Microbiology Research Center, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA. .,Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA.
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654
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Paraskevopoulou V, Schimpl M, Overman RC, Stolnik S, Chen Y, Nguyen L, Winkler GS, Gellert P, Klassen JS, Falcone FH. Structural and binding characterization of the LacdiNAc-specific adhesin (LabA; HopD) exodomain from Helicobacter pylori. Curr Res Struct Biol 2020; 3:19-29. [PMID: 34235483 PMCID: PMC8244420 DOI: 10.1016/j.crstbi.2020.12.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 10/31/2020] [Accepted: 12/10/2020] [Indexed: 01/02/2023] Open
Abstract
Helicobacter pylori (H. pylori) uses several outer membrane proteins for adhering to its host's gastric mucosa, an important step in establishing and preserving colonization. Several adhesins (SabA, BabA, HopQ) have been characterized in terms of their three-dimensional structure. A recent addition to the growing list of outer membrane porins is LabA (LacdiNAc-binding adhesin), which is thought to bind specifically to GalNAcβ1-4GlcNAc, occurring in the gastric mucosa. LabA47-496 protein expressed as His-tagged protein in the periplasm of E. coli and purified via subtractive IMAC after TEV cleavage and subsequent size exclusion chromatography, resulted in bipyramidal crystals with good diffraction properties. Here, we describe the 2.06 Å resolution structure of the exodomain of LabA from H. pylori strain J99 (PDB ID: 6GMM). Strikingly, despite the relatively low levels of sequence identity with the other three structurally characterized adhesins (20-49%), LabA shares an L-shaped fold with SabA and BabA. The 'head' region contains a 4 + 3 α-helix bundle, with a small insertion domain consisting of a short antiparallel beta sheet and an unstructured region, not resolved in the crystal structure. Sequence alignment of LabA from different strains shows a high level of conservation in the N- and C-termini, and identifies two main types based on the length of the insertion domain ('crown' region), the 'J99-type' (insertion ~31 amino acids), and the H. pylori '26695 type' (insertion ~46 amino acids). Analysis of ligand binding using Native Electrospray Ionization Mass Spectrometry (ESI-MS) together with solid phase-bound, ELISA-type assays could not confirm the originally described binding of GalNAcβ1-4GlcNAc-containing oligosaccharides, in line with other recent reports, which also failed to confirm LacdiNAc binding.
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Affiliation(s)
| | - Marianne Schimpl
- Structure, Biophysics and Fragment-based Lead Generation, Discovery Sciences, R&D, AstraZeneca, Cambridge, United Kingdom
| | - Ross C. Overman
- Protein Science, Discovery Sciences, R&D, AstraZeneca, Alderley Park, United Kingdom
| | - Snow Stolnik
- School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, United Kingdom
| | - Yajie Chen
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, T6G 2G2, Canada
| | - Linh Nguyen
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, T6G 2G2, Canada
| | | | - Paul Gellert
- Innovation Strategy & External Liaison, Pharmaceutical Technology & Development, Operations, AstraZeneca, Macclesfield, United Kingdom
| | - John S. Klassen
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, T6G 2G2, Canada
| | - Franco H. Falcone
- School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, United Kingdom
- Institute for Parasitology, Justus-Liebig-University Gießen, Schubertstr. 81, D-35392, Gießen, Germany
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655
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Sengupta D, Bhattacharya G, Ganguli S, Sengupta M. Structural insights and evaluation of the potential impact of missense variants on the interactions of SLIT2 with ROBO1/4 in cancer progression. Sci Rep 2020; 10:21909. [PMID: 33318575 PMCID: PMC7736846 DOI: 10.1038/s41598-020-78882-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 12/01/2020] [Indexed: 02/07/2023] Open
Abstract
The cognate interaction of ROBO1/4 with its ligand SLIT2 is known to be involved in lung cancer progression. However, the precise role of genetic variants, disrupting the molecular interactions is less understood. All cancer-associated missense variants of ROBO1/4 and SLIT2 from COSMIC were screened for their pathogenicity. Homology modelling was done in Modeller 9.17, followed by molecular simulation in GROMACS. Rigid docking was performed for the cognate partners in PatchDock with refinement in HADDOCK server. Post-docking alterations in conformational, stoichiometric, as well as structural parameters, were assessed. The disruptive variants were ranked using a weighted scoring scheme. In silico prioritisation of 825 variants revealed 379 to be potentially pathogenic out of which, about 12% of the variants, i.e. ROBO1 (14), ROBO4 (8), and SLIT2 (23) altered the cognate docking. Six variants of ROBO1 and 5 variants of ROBO4 were identified as "high disruptors" of interactions with SLIT2 wild type. Likewise, 17 and 13 variants of SLIT2 were found to be "high disruptors" of its interaction with ROBO1 and ROBO4, respectively. Our study is the first report on the impact of cancer-associated missense variants on ROBO1/4 and SLIT2 interactions that might be the drivers of lung cancer progression.
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Affiliation(s)
- Debmalya Sengupta
- Department of Genetics, University of Calcutta, University College of Science (UCSTA), 35, Ballygunge Circular Road, Kolkata, 700 019, India
| | - Gairika Bhattacharya
- Department of Genetics, University of Calcutta, University College of Science (UCSTA), 35, Ballygunge Circular Road, Kolkata, 700 019, India
- Cactus Communications, Mumbai, India
| | - Sayak Ganguli
- Department of Biotechnology, St. Xavier's College (Autonomous), 30, Mother Teresa Sarani, Kolkata, 700 016, India.
| | - Mainak Sengupta
- Department of Genetics, University of Calcutta, University College of Science (UCSTA), 35, Ballygunge Circular Road, Kolkata, 700 019, India.
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656
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Anbo H, Amagai H, Fukuchi S. NeProc predicts binding segments in intrinsically disordered regions without learning binding region sequences. Biophys Physicobiol 2020; 17:147-154. [PMID: 33304713 PMCID: PMC7692026 DOI: 10.2142/biophysico.bsj-2020026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 10/29/2020] [Indexed: 12/01/2022] Open
Abstract
Intrinsically disordered proteins are those proteins with intrinsically disordered regions. One of the unique characteristics of intrinsically disordered proteins is the existence of functional segments in intrinsically dis-ordered regions. These segments are involved in binding to partner molecules, such as protein and DNA, and play important roles in signaling pathways and/or transcriptional regulation. Although there are databases that gather information on such disordered binding regions, data remain limited. Therefore, it is desirable to develop programs to predict the disordered binding regions without using data for the binding regions. We developed a program, NeProc, to predict the disordered binding regions, which can be regarded as intrinsically disordered regions with a structural propensity. We only used data for the structural domains and intrinsically disordered regions to detect such regions. NeProc accepts a query amino acid sequence converted into a position specific score matrix, and uses two neural networks that employ different window sizes, a neural network of short windows, and a neural network of long windows. The performance of NeProc was comparable to that of existing programs of the disordered binding region prediction. This result presents the possibility to overcome the shortage of the disordered binding region data in the development of the prediction programs for these binding regions. NeProc is available at http://flab.neproc.org/neproc/index.html.
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Affiliation(s)
- Hiroto Anbo
- Department of Life Science and Informatics, Faculty of Engineering, Maebashi Institute of Technology, Maebashi, Gunma 371-0816, Japan
| | - Hiroki Amagai
- Department of Life Science and Informatics, Faculty of Engineering, Maebashi Institute of Technology, Maebashi, Gunma 371-0816, Japan
| | - Satoshi Fukuchi
- Department of Life Science and Informatics, Faculty of Engineering, Maebashi Institute of Technology, Maebashi, Gunma 371-0816, Japan
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657
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A serine protease secreted from Bacillus subtilis cleaves human plasma transthyretin to generate an amyloidogenic fragment. Commun Biol 2020; 3:764. [PMID: 33311636 PMCID: PMC7733459 DOI: 10.1038/s42003-020-01493-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 11/16/2020] [Indexed: 12/14/2022] Open
Abstract
Aggregation of human wild-type transthyretin (hTTR), a homo-tetrameric plasma protein, leads to acquired senile systemic amyloidosis (SSA), recently recognised as a major cause of cardiomyopathies in 1-3% older adults. Fragmented hTTR is the standard composition of amyloid deposits in SSA, but the protease(s) responsible for amyloidogenic fragments generation in vivo is(are) still elusive. Here, we show that subtilisin secreted from Bacillus subtilis, a gut microbiota commensal bacterium, translocates across a simulated intestinal epithelium and cleaves hTTR both in solution and human plasma, generating the amyloidogenic fragment hTTR(59-127), which is also found in SSA amyloids in vivo. To the best of our knowledge, these findings highlight a novel pathogenic mechanism for SSA whereby increased permeability of the gut mucosa, as often occurs in elderly people, allows subtilisin (and perhaps other yet unidentified bacterial proteases) to reach the bloodstream and trigger generation of hTTR fragments, acting as seeding nuclei for preferential amyloid fibrils deposition in the heart.
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658
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Krajnc A, Gaber A, Lenarčič B, Pavšič M. The Central Region of Testican-2 Forms a Compact Core and Promotes Cell Migration. Int J Mol Sci 2020; 21:ijms21249413. [PMID: 33321927 PMCID: PMC7763218 DOI: 10.3390/ijms21249413] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/05/2020] [Accepted: 12/08/2020] [Indexed: 01/25/2023] Open
Abstract
Testicans are modular proteoglycans of the extracellular matrix of various tissues where they contribute to matrix integrity and exert cellular effects like neurite outgrowth and cell migration. Using testican-2 as a representative member of the family, we tackle the complete lack of general structural information and structure-function relationship. First, we show using isothermal titration calorimetry and modeling that extracellular calcium-binding domain (EC) has only one active calcium-binding site, while the other potential site is inactive, and that testican-2 is within extracellular matrix always in the calcium-loaded form. Next, we demonstrate using various prediction methods that N- and C-terminal regions plus interdomain connections are flexible. We support this by small-angle X-ray-scattering analysis of C-terminally truncated testican-2, which indicates that the triplet follistatin-EC-thyroglobulin domain forms a moderately compact core while the unique N-terminal is disordered. Finally, using cell exclusion zone assay, we show that it is this domain triplet that is responsible for promoting cell migration and not the N- and C-terminal regions.
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Affiliation(s)
- Anja Krajnc
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (A.K.); (A.G.); (B.L.)
| | - Aljaž Gaber
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (A.K.); (A.G.); (B.L.)
| | - Brigita Lenarčič
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (A.K.); (A.G.); (B.L.)
- Department of Biochemistry, Molecular and Structural Biology, Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
| | - Miha Pavšič
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (A.K.); (A.G.); (B.L.)
- Correspondence: ; Tel.: +386-1-479-8550
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659
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Bhopatkar AA, Rangachari V. Are granulins copper sequestering proteins? Proteins 2020; 89:450-461. [PMID: 33252789 DOI: 10.1002/prot.26031] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 11/25/2020] [Indexed: 02/06/2023]
Abstract
Granulins (GRN 1-7) are short (~6 kDa), cysteine-rich proteins that are generated upon the proteolytic processing of progranulin (PGRN). These peptides, along with their precursor, have been implicated in multiple pathophysiological roles, especially in neurodegenerative diseases. Previously we showed that GRN-3 and GRN-5 are fully disordered in the reduced form implicating redox sensitive attributes to the proteins. Redox-based modulations are often carried out by metalloproteins in mitigating oxidative stress and maintaining metal-homeostasis within cells. To probe whether GRNs play a role in metal sequestration, we tested the metal binding propensity of the reduced forms of GRNs -3 and - 5 under neutral and acidic pH mimicking cytosolic and lysosomal conditions, respectively. We found, at neutral pH, both GRNs selectively bind Cu and no other divalent metal cations, with a greater specificity for Cu(I). Binding of Cu did not result in a disorder-to-order structural transition but partly triggered the multimerization of GRNs via uncoordinated cystines at both pH conditions. Overall, the results indicate that GRNs -3 and - 5 have surprisingly strong affinity for Cu in the pM range, comparable to other known copper sequestering proteins. The results also hint at a potential of GRNs to reduce Cu(II) to Cu(I), a process that has significance in mitigating Cu-induced ROS cytotoxicity in cells. Together, this report uncovers metal-coordinating property of GRNs for the first time, which may have profound significance in their structure and pathophysiological functions.
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Affiliation(s)
- Anukool A Bhopatkar
- Department of Chemistry and Biochemistry, School of Mathematics and Natural Sciences and, University of Southern Mississippi, Hattiesburg, Mississippi, USA
| | - Vijayaraghavan Rangachari
- Center for Molecular and Cellular Biosciences, University of Southern Mississippi, Hattiesburg, Mississippi, USA
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660
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Katuwawala A, Kurgan L. Comparative Assessment of Intrinsic Disorder Predictions with a Focus on Protein and Nucleic Acid-Binding Proteins. Biomolecules 2020; 10:E1636. [PMID: 33291838 PMCID: PMC7762010 DOI: 10.3390/biom10121636] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 11/26/2020] [Accepted: 12/03/2020] [Indexed: 01/18/2023] Open
Abstract
With over 60 disorder predictors, users need help navigating the predictor selection task. We review 28 surveys of disorder predictors, showing that only 11 include assessment of predictive performance. We identify and address a few drawbacks of these past surveys. To this end, we release a novel benchmark dataset with reduced similarity to the training sets of the considered predictors. We use this dataset to perform a first-of-its-kind comparative analysis that targets two large functional families of disordered proteins that interact with proteins and with nucleic acids. We show that limiting sequence similarity between the benchmark and the training datasets has a substantial impact on predictive performance. We also demonstrate that predictive quality is sensitive to the use of the well-annotated order and inclusion of the fully structured proteins in the benchmark datasets, both of which should be considered in future assessments. We identify three predictors that provide favorable results using the new benchmark set. While we find that VSL2B offers the most accurate and robust results overall, ESpritz-DisProt and SPOT-Disorder perform particularly well for disordered proteins. Moreover, we find that predictions for the disordered protein-binding proteins suffer low predictive quality compared to generic disordered proteins and the disordered nucleic acids-binding proteins. This can be explained by the high disorder content of the disordered protein-binding proteins, which makes it difficult for the current methods to accurately identify ordered regions in these proteins. This finding motivates the development of a new generation of methods that would target these difficult-to-predict disordered proteins. We also discuss resources that support users in collecting and identifying high-quality disorder predictions.
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Affiliation(s)
| | - Lukasz Kurgan
- Department of Computer Science, Virginia Commonwealth University, Richmond, VA 23284, USA;
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661
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Ree R, Kind L, Kaziales A, Varland S, Dai M, Richter K, Drazic A, Arnesen T. PFN2 and NAA80 cooperate to efficiently acetylate the N-terminus of actin. J Biol Chem 2020; 295:16713-16731. [PMID: 32978259 PMCID: PMC7864067 DOI: 10.1074/jbc.ra120.015468] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/22/2020] [Indexed: 12/01/2022] Open
Abstract
The actin cytoskeleton is of profound importance to cell shape, division, and intracellular force generation. Profilins bind to globular (G-)actin and regulate actin filament formation. Although profilins are well-established actin regulators, the distinct roles of the dominant profilin, profilin 1 (PFN1), versus the less abundant profilin 2 (PFN2) remain enigmatic. In this study, we use interaction proteomics to discover that PFN2 is an interaction partner of the actin N-terminal acetyltransferase NAA80, and further confirm this by analytical ultracentrifugation. Enzyme assays with NAA80 and different profilins demonstrate that PFN2 binding specifically increases the intrinsic catalytic activity of NAA80. NAA80 binds PFN2 through a proline-rich loop, deletion of which abrogates PFN2 binding. Small-angle X-ray scattering shows that NAA80, actin, and PFN2 form a ternary complex and that NAA80 has partly disordered regions in the N-terminus and the proline-rich loop, the latter of which is partly ordered upon PFN2 binding. Furthermore, binding of PFN2 to NAA80 via the proline-rich loop promotes binding between the globular domains of actin and NAA80, and thus acetylation of actin. However, the majority of cellular NAA80 is stably bound to PFN2 and not to actin, and we propose that this complex acetylates G-actin before it is incorporated into filaments. In conclusion, we reveal a functionally specific role of PFN2 as a stable interactor and regulator of the actin N-terminal acetyltransferase NAA80, and establish the modus operandi for NAA80-mediated actin N-terminal acetylation, a modification with a major impact on cytoskeletal dynamics.
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Affiliation(s)
- Rasmus Ree
- Department of Biomedicine, University of Bergen, Bergen, Norway.
| | - Laura Kind
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Anna Kaziales
- Department of Chemistry, Technische Universität München, Garching, Germany
| | - Sylvia Varland
- Department of Biomedicine, University of Bergen, Bergen, Norway; Department of Biological Sciences, University of Bergen, Bergen, Norway
| | - Minglu Dai
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Klaus Richter
- Department of Chemistry, Technische Universität München, Garching, Germany
| | - Adrian Drazic
- Department of Biomedicine, University of Bergen, Bergen, Norway.
| | - Thomas Arnesen
- Department of Biomedicine, University of Bergen, Bergen, Norway; Department of Biological Sciences, University of Bergen, Bergen, Norway; Department of Surgery, Haukeland University Hospital, Bergen, Norway
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662
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Marmor-Kollet H, Siany A, Kedersha N, Knafo N, Rivkin N, Danino YM, Moens TG, Olender T, Sheban D, Cohen N, Dadosh T, Addadi Y, Ravid R, Eitan C, Toth Cohen B, Hofmann S, Riggs CL, Advani VM, Higginbottom A, Cooper-Knock J, Hanna JH, Merbl Y, Van Den Bosch L, Anderson P, Ivanov P, Geiger T, Hornstein E. Spatiotemporal Proteomic Analysis of Stress Granule Disassembly Using APEX Reveals Regulation by SUMOylation and Links to ALS Pathogenesis. Mol Cell 2020; 80:876-891.e6. [PMID: 33217318 PMCID: PMC7816607 DOI: 10.1016/j.molcel.2020.10.032] [Citation(s) in RCA: 132] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 07/30/2020] [Accepted: 10/22/2020] [Indexed: 10/23/2022]
Abstract
Stress granules (SGs) are cytoplasmic assemblies of proteins and non-translating mRNAs. Whereas much has been learned about SG formation, a major gap remains in understanding the compositional changes SGs undergo during normal disassembly and under disease conditions. Here, we address this gap by proteomic dissection of the SG temporal disassembly sequence using multi-bait APEX proximity proteomics. We discover 109 novel SG proteins and characterize distinct SG substructures. We reveal dozens of disassembly-engaged proteins (DEPs), some of which play functional roles in SG disassembly, including small ubiquitin-like modifier (SUMO) conjugating enzymes. We further demonstrate that SUMOylation regulates SG disassembly and SG formation. Parallel proteomics with amyotrophic lateral sclerosis (ALS)-associated C9ORF72 dipeptides uncovered attenuated DEP recruitment during SG disassembly and impaired SUMOylation. Accordingly, SUMO activity ameliorated C9ORF72-ALS-related neurodegeneration in Drosophila. By dissecting the SG spatiotemporal proteomic landscape, we provide an in-depth resource for future work on SG function and reveal basic and disease-relevant mechanisms of SG disassembly.
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Affiliation(s)
- Hagai Marmor-Kollet
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Aviad Siany
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Nancy Kedersha
- Division of Rheumatology, Immunity, and Inflammation, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Harvard Medical School Initiative for RNA Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Naama Knafo
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Natalia Rivkin
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Yehuda M Danino
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Thomas G Moens
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Tsviya Olender
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Daoud Sheban
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel; Department of Immunology, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Nir Cohen
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Tali Dadosh
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Yoseph Addadi
- Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Revital Ravid
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Chen Eitan
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Beata Toth Cohen
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Sarah Hofmann
- Division of Rheumatology, Immunity, and Inflammation, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Harvard Medical School Initiative for RNA Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Claire L Riggs
- Division of Rheumatology, Immunity, and Inflammation, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Harvard Medical School Initiative for RNA Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Vivek M Advani
- Division of Rheumatology, Immunity, and Inflammation, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Harvard Medical School Initiative for RNA Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Adrian Higginbottom
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield S10 2HQ, UK
| | - Johnathan Cooper-Knock
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield S10 2HQ, UK
| | - Jacob H Hanna
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Yifat Merbl
- Department of Immunology, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Ludo Van Den Bosch
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Paul Anderson
- Division of Rheumatology, Immunity, and Inflammation, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Harvard Medical School Initiative for RNA Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Pavel Ivanov
- Division of Rheumatology, Immunity, and Inflammation, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Harvard Medical School Initiative for RNA Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Tamar Geiger
- Harvard Medical School Initiative for RNA Medicine, Harvard Medical School, Boston, MA 02115, USA; Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel.
| | - Eran Hornstein
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel.
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The exquisite structural biophysics of the Golgi Reassembly and Stacking Proteins. Int J Biol Macromol 2020; 164:3632-3644. [DOI: 10.1016/j.ijbiomac.2020.08.203] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/20/2020] [Accepted: 08/26/2020] [Indexed: 12/13/2022]
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664
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England SJ, Cerda GA, Kowalchuk A, Sorice T, Grieb G, Lewis KE. Hmx3a Has Essential Functions in Zebrafish Spinal Cord, Ear and Lateral Line Development. Genetics 2020; 216:1153-1185. [PMID: 33077489 PMCID: PMC7768253 DOI: 10.1534/genetics.120.303748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 10/14/2020] [Indexed: 11/30/2022] Open
Abstract
Transcription factors that contain a homeodomain DNA-binding domain have crucial functions in most aspects of cellular function and embryonic development in both animals and plants. Hmx proteins are a subfamily of NK homeodomain-containing proteins that have fundamental roles in development of sensory structures such as the eye and the ear. However, Hmx functions in spinal cord development have not been analyzed. Here, we show that zebrafish (Danio rerio) hmx2 and hmx3a are coexpressed in spinal dI2 and V1 interneurons, whereas hmx3b, hmx1, and hmx4 are not expressed in spinal cord. Using mutational analyses, we demonstrate that, in addition to its previously reported role in ear development, hmx3a is required for correct specification of a subset of spinal interneuron neurotransmitter phenotypes, as well as correct lateral line progression and survival to adulthood. Surprisingly, despite similar expression patterns of hmx2 and hmx3a during embryonic development, zebrafish hmx2 mutants are viable and have no obviously abnormal phenotypes in sensory structures or neurons that require hmx3a In addition, embryos homozygous for deletions of both hmx2 and hmx3a have identical phenotypes to severe hmx3a single mutants. However, mutating hmx2 in hypomorphic hmx3a mutants that usually develop normally, results in abnormal ear and lateral line phenotypes. This suggests that while hmx2 cannot compensate for loss of hmx3a, it does function in these developmental processes, although to a much lesser extent than hmx3a More surprisingly, our mutational analyses suggest that Hmx3a may not require its homeodomain DNA-binding domain for its roles in viability or embryonic development.
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Affiliation(s)
| | - Gustavo A Cerda
- Department of Physiology, Development and Neuroscience, University of Cambridge, CB2 3DY, UK
| | | | - Taylor Sorice
- Department of Biology, Syracuse University, New York 13244
| | - Ginny Grieb
- Department of Biology, Syracuse University, New York 13244
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665
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Abstract
The human immunodeficiency virus type 1 (HIV-1) proteome is expressed from alternatively spliced and unspliced genomic RNAs. However, HIV-1 RNAs that are not fully spliced are perceived by the host machinery as defective and are retained in the nucleus. During late infection, HIV-1 bypasses this regulatory mechanism by expression of the Rev protein from a fully spliced mRNA. Once imported into the nucleus, Rev mediates the export of unprocessed HIV-1 RNAs to the cytoplasm, leading to the production of the viral progeny. While regarded as a canonical RNA export factor, Rev has also been linked to HIV-1 RNA translation, stabilization, splicing and packaging. However, Rev's functions beyond RNA export have remained poorly understood. Here, we revisit this paradigmatic protein, reviewing recent data investigating its structure and function. We conclude by asking: what remains unknown about this enigmatic viral protein?
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Affiliation(s)
| | - Aino Järvelin
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Ilan Davis
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Alfredo Castello
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
- MRC-University of Glasgow Centre for Virus Research, University of Glasgow, 464 Bearsden Road, Glasgow G61 1QH, UK
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666
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Karman Z, Rethi-Nagy Z, Abraham E, Fabri-Ordogh L, Csonka A, Vilmos P, Debski J, Dadlez M, Glover DM, Lipinszki Z. Novel perspectives of target-binding by the evolutionarily conserved PP4 phosphatase. Open Biol 2020; 10:200343. [PMID: 33352067 PMCID: PMC7776573 DOI: 10.1098/rsob.200343] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 11/27/2020] [Indexed: 02/06/2023] Open
Abstract
Protein phosphatase 4 (PP4) is an evolutionarily conserved and essential Ser/Thr phosphatase that regulates cell division, development and DNA repair in eukaryotes. The major form of PP4, present from yeast to human, is the PP4c-R2-R3 heterotrimeric complex. The R3 subunit is responsible for substrate-recognition via its EVH1 domain. In typical EVH1 domains, conserved phenylalanine, tyrosine and tryptophan residues form the specific recognition site for their target's proline-rich sequences. Here, we identify novel binding partners of the EVH1 domain of the Drosophila R3 subunit, Falafel, and demonstrate that instead of binding to proline-rich sequences this EVH1 variant specifically recognizes atypical ligands, namely the FxxP and MxPP short linear consensus motifs. This interaction is dependent on an exclusively conserved leucine that replaces the phenylalanine invariant of all canonical EVH1 domains. We propose that the EVH1 domain of PP4 represents a new class of the EVH1 family that can accommodate low proline content sequences, such as the FxxP motif. Finally, our data implicate the conserved Smk-1 domain of Falafel in target-binding. These findings greatly enhance our understanding of the substrate-recognition mechanisms and function of PP4.
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Affiliation(s)
- Zoltan Karman
- Biological Research Centre, Institute of Biochemistry, MTA Lendület Laboratory of Cell Cycle Regulation, Szeged, H‐6726, Hungary
- Doctoral School of Biology, Faculty of Science and Informatics, University of Szeged, Szeged, H‐6725, Hungary
| | - Zsuzsanna Rethi-Nagy
- Biological Research Centre, Institute of Biochemistry, MTA Lendület Laboratory of Cell Cycle Regulation, Szeged, H‐6726, Hungary
- Doctoral School of Biology, Faculty of Science and Informatics, University of Szeged, Szeged, H‐6725, Hungary
| | - Edit Abraham
- Biological Research Centre, Institute of Biochemistry, MTA Lendület Laboratory of Cell Cycle Regulation, Szeged, H‐6726, Hungary
| | - Lilla Fabri-Ordogh
- Biological Research Centre, Institute of Biochemistry, MTA Lendület Laboratory of Cell Cycle Regulation, Szeged, H‐6726, Hungary
| | - Akos Csonka
- Department of Traumatology, University of Szeged, Szeged, H‐6725, Hungary
| | - Peter Vilmos
- Biological Research Centre, Institute of Genetics, Szeged, H‐6726, Hungary
| | - Janusz Debski
- Laboratory of Mass Spectrometry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Michal Dadlez
- Laboratory of Mass Spectrometry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - David M. Glover
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
- California Institute of Technology, Pasadena, CA 91125, USA
| | - Zoltan Lipinszki
- Biological Research Centre, Institute of Biochemistry, MTA Lendület Laboratory of Cell Cycle Regulation, Szeged, H‐6726, Hungary
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667
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Teyra J, Kelil A, Jain S, Helmy M, Jajodia R, Hooda Y, Gu J, D’Cruz AA, Nicholson SE, Min J, Sudol M, Kim PM, Bader GD, Sidhu SS. Large-scale survey and database of high affinity ligands for peptide recognition modules. Mol Syst Biol 2020; 16:e9310. [PMID: 33438817 PMCID: PMC7724964 DOI: 10.15252/msb.20199310] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 11/03/2020] [Accepted: 11/04/2020] [Indexed: 12/13/2022] Open
Abstract
Many proteins involved in signal transduction contain peptide recognition modules (PRMs) that recognize short linear motifs (SLiMs) within their interaction partners. Here, we used large-scale peptide-phage display methods to derive optimal ligands for 163 unique PRMs representing 79 distinct structural families. We combined the new data with previous data that we collected for the large SH3, PDZ, and WW domain families to assemble a database containing 7,984 unique peptide ligands for 500 PRMs representing 82 structural families. For 74 PRMs, we acquired enough new data to map the specificity profiles in detail and derived position weight matrices and binding specificity logos based on multiple peptide ligands. These analyses showed that optimal peptide ligands resembled peptides observed in existing structures of PRM-ligand complexes, indicating that a large majority of the phage-derived peptides are likely to target natural peptide-binding sites and could thus act as inhibitors of natural protein-protein interactions. The complete dataset has been assembled in an online database (http://www.prm-db.org) that will enable many structural, functional, and biological studies of PRMs and SLiMs.
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Affiliation(s)
- Joan Teyra
- The Donnelly CentreUniversity of TorontoTorontoONCanada
| | | | - Shobhit Jain
- The Donnelly CentreUniversity of TorontoTorontoONCanada
- Department of Computer ScienceUniversity of TorontoTorontoONCanada
| | - Mohamed Helmy
- The Donnelly CentreUniversity of TorontoTorontoONCanada
- Present address:
Singapore Institute of Food and Biotechnology Innovation (SIFBI)Agency for ScienceTechnology and Research (A*STAR)Singapore CitySingapore
| | - Raghav Jajodia
- Indian Institute of Engineering Science and TechnologyShibpurIndia
| | - Yogesh Hooda
- The Donnelly CentreUniversity of TorontoTorontoONCanada
- Present address:
MRC Laboratory of Molecular BiologyCambridgeUK
| | - Jun Gu
- The Donnelly CentreUniversity of TorontoTorontoONCanada
| | - Akshay A D’Cruz
- The Walter and Eliza Hall Institute of Medical ResearchParkvilleVic.Australia
| | - Sandra E Nicholson
- The Walter and Eliza Hall Institute of Medical ResearchParkvilleVic.Australia
| | - Jinrong Min
- Structural Genomics ConsortiumUniversity of TorontoTorontoONCanada
- Department of PhysiologyUniversity of TorontoTorontoONCanada
| | - Marius Sudol
- Department of MedicineIcahn School of Medicine at Mount SinaiNew YorkNYUSA
| | - Philip M Kim
- The Donnelly CentreUniversity of TorontoTorontoONCanada
- Department of Computer ScienceUniversity of TorontoTorontoONCanada
- Department of Molecular GeneticsUniversity of TorontoTorontoONCanada
| | - Gary D Bader
- The Donnelly CentreUniversity of TorontoTorontoONCanada
- Department of Computer ScienceUniversity of TorontoTorontoONCanada
- Department of Molecular GeneticsUniversity of TorontoTorontoONCanada
| | - Sachdev S Sidhu
- The Donnelly CentreUniversity of TorontoTorontoONCanada
- Department of Molecular GeneticsUniversity of TorontoTorontoONCanada
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668
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Cusick JK, Alhomsy Y, Wong S, Talbott G, Uversky VN, Hart C, Hejazi N, Jacobs AT, Shi Y. RELT stains prominently in B-cell lymphomas and binds the hematopoietic transcription factor MDFIC. Biochem Biophys Rep 2020; 24:100868. [PMID: 33367115 PMCID: PMC7749370 DOI: 10.1016/j.bbrep.2020.100868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 11/02/2020] [Accepted: 11/23/2020] [Indexed: 11/30/2022] Open
Abstract
Receptor Expressed in Lymphoid Tissues (RELT) is a human tumor necrosis factor receptor superfamily member (TNFRSF) that is expressed most prominently in cells and tissues of the hematopoietic system. RELL1 and RELL2 are two homologs that physically interact with RELT and co-localize with RELT at the plasma membrane. This study sought to further elucidate the function of RELT by identifying novel protein interactions with RELT family members. The transcription factor MyoD family inhibitor domain-containing (MDFIC) was identified in a yeast two-hybrid genetic screen using RELL1 as bait. MDFIC co-localizes with RELT family members at the plasma membrane; this co-localization was most prominently observed with RELL1 and RELL2. In vitro co-immunoprecipitation (Co-IP) was utilized to demonstrate that MDFIC physically interacts with RELT, RELL1, and RELL2. Co-IP using deletion mutants of MDFIC and RELT identified regions important for physical association between MDFIC and RELT family members and a computational analysis revealed that RELT family members are highly disordered proteins. Immunohistochemistry of normal human lymph nodes revealed RELT staining that was most prominent in macrophages. Interestingly, the level of RELT staining significantly increased progressively in low and high-grade B-cell lymphomas versus normal lymph nodes. RELT co-staining with CD20 was observed in B-cell lymphomas, indicating that RELT is expressed in malignant B cells. Collectively, these results further our understanding of RELT-associated signaling pathways, the protein structure of RELT family members, and provide preliminary evidence indicating an association of RELT with B-cell lymphomas.
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Affiliation(s)
- John K. Cusick
- Department of Basic Science, California Northstate University, College of Medicine, Elk Grove, CA, 95757, USA
| | - Yasmeen Alhomsy
- Department of Basic Science, California Northstate University, College of Medicine, Elk Grove, CA, 95757, USA
| | - Stephanie Wong
- Department of Medical Education, California University of Science and Medicine, San Bernardino, CA, 92408, USA
| | - George Talbott
- Department of Pharmaceutical and Biomedical Sciences, California Northstate University College of Pharmacy, Elk Grove, CA, 95757, USA
| | - Vladimir N. Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA
| | - Cara Hart
- Department of Biology, The University of Hawaii at Hilo, Hilo, HI, 96720, USA
| | - Nazila Hejazi
- Department of Clinical Science, California Northstate University, College of Medicine, Elk Grove, CA, 95757, USA
| | - Aaron T. Jacobs
- Department of Medical Education, California University of Science and Medicine, San Bernardino, CA, 92408, USA
| | - Yihui Shi
- Department of Basic Science, California Northstate University, College of Medicine, Elk Grove, CA, 95757, USA
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669
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Klein TA, Grebenc DW, Gandhi SY, Shah VS, Kim Y, Whitney JC. Structure of the Extracellular Region of the Bacterial Type VIIb Secretion System Subunit EsaA. Structure 2020; 29:177-185.e6. [PMID: 33238147 DOI: 10.1016/j.str.2020.11.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/17/2020] [Accepted: 11/02/2020] [Indexed: 12/15/2022]
Abstract
Gram-positive bacteria use type VII secretion systems (T7SSs) to export effector proteins that manipulate the physiology of nearby prokaryotic and eukaryotic cells. Several mycobacterial T7SSs have established roles in virulence. By contrast, the genetically distinct T7SSb pathway found in Firmicutes bacteria more often functions to mediate bacterial competition. A lack of structural information on the T7SSb has limited the understanding of effector export by this protein secretion apparatus. Here, we present the 2.4 Å crystal structure of the extracellular region of the T7SSb subunit EsaA from Streptococcus gallolyticus. Our structure reveals that homodimeric EsaA is an elongated, arrow-shaped protein with a surface-accessible "tip", which in some species of bacteria serves as a receptor for lytic bacteriophages. Because it is the only T7SSb subunit large enough to traverse the peptidoglycan layer of Firmicutes, we propose that EsaA plays a critical role in transporting effectors across the entirety of the Gram-positive cell envelope.
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Affiliation(s)
- Timothy A Klein
- Michael DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON L8S 4K1, Canada; Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Dirk W Grebenc
- Michael DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON L8S 4K1, Canada; Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Shil Y Gandhi
- Michael DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON L8S 4K1, Canada; Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Vraj S Shah
- Michael DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON L8S 4K1, Canada; Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Youngchang Kim
- Structural Biology Center, X-ray Science, Argonne National Laboratory, Argonne, IL, USA
| | - John C Whitney
- Michael DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON L8S 4K1, Canada; Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada; David Braley Centre for Antibiotic Discovery, McMaster University, Hamilton, ON L8S 4K1, Canada.
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670
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Vázquez-Martínez JA, Gómez-Lim MA, Morales-Ríos E, Gonzalez-y-Merchand JA, Ortiz-Navarrete V. Short Disordered Epitope of CRTAM Ig-Like V Domain as a Potential Target for Blocking Antibodies. Int J Mol Sci 2020; 21:ijms21228798. [PMID: 33233764 PMCID: PMC7699905 DOI: 10.3390/ijms21228798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/16/2020] [Accepted: 11/16/2020] [Indexed: 11/25/2022] Open
Abstract
Class-I Restricted T Cell-Associated Molecule (CRTAM) is a protein that is expressed after T cell activation. The interaction of CRTAM with its ligand, nectin-like 2 (Necl2), is required for the efficient production of IL-17, IL-22, and IFNγ by murine CD4 T cells, and it plays a role in optimal CD8 T and NK cell cytotoxicity. CRTAM promotes the pro-inflammatory cytokine profile; therefore, it may take part in the immunopathology of autoimmune diseases such as diabetes type 1 or colitis. Thus, antibodies that block the interaction between CRTAM and Necl2 would be useful for controlling the production of these inflammatory cytokines. In this work, using bioinformatics predictions, we identified three short disordered epitopes (sDE1-3) that are located in the Ig-like domains of murine CRTAM and are conserved in mammalian species. We performed a structural analysis by molecular dynamics simulations of sDE1 (QHPALKSSKY, Ig-like V), sDE2 (QRNGEKSVVK, Ig-like C1), and sDE3 (CSTERSKKPPPQI, Ig-like C1). sDE1, which is located within a loop of the contact interface of the heterotypic interaction with Nectl2, undergoes an order–disorder transition. On the contrary, even though sDE2 and sDE3 are flexible and also located within loops, they do not undergo order–disorder transitions. We evaluated the immunogenicity of sDE1 and sDE3 through the expression of these epitopes in chimeric L1 virus-like particles. We confirmed that sDE1 induces polyclonal antibodies that recognize the native folding of CRTAM expressed in activated murine CD4 T cells. In contrast, sDE3 induces polyclonal antibodies that recognize the recombinant protein hCRTAM-Fc, but not the native CRTAM. Thus, in this study, an exposed disordered epitope in the Ig-like V domain of CRTAM was identified as a potential site for therapeutic antibodies.
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Affiliation(s)
- Julio Angel Vázquez-Martínez
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, 11340 Ciudad de Mexico, Mexico; (J.A.V.-M.); (J.A.G.-y.-M.)
- Departamento de Biomedicina Molecular, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), 07360 Ciudad de Mexico, Mexico
- Departamento de Ingeniería Genética, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), 36821 Irapuato, Guanajuato, Mexico;
| | - Miguel Angel Gómez-Lim
- Departamento de Ingeniería Genética, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), 36821 Irapuato, Guanajuato, Mexico;
| | - Edgar Morales-Ríos
- Departamento de Bioquímica, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), 07360 Ciudad de Mexico, Mexico;
| | - Jorge Alberto Gonzalez-y-Merchand
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, 11340 Ciudad de Mexico, Mexico; (J.A.V.-M.); (J.A.G.-y.-M.)
| | - Vianney Ortiz-Navarrete
- Departamento de Biomedicina Molecular, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), 07360 Ciudad de Mexico, Mexico
- Correspondence:
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671
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The Clostridioides difficile Cysteine-Rich Exosporium Morphogenetic Protein, CdeC, Exhibits Self-Assembly Properties That Lead to Organized Inclusion Bodies in Escherichia coli. mSphere 2020; 5:5/6/e01065-20. [PMID: 33208520 PMCID: PMC7677010 DOI: 10.1128/msphere.01065-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The endospore of Clostridioides difficile is the vehicle for transmission and persistence of the pathogen, and, specifically, the exosporium is the first contact between the host and the spore. The underlying mechanisms that govern exosporium assembly in C. difficile remain understudied, in part due to difficulties in obtaining pure soluble recombinant proteins of the C. difficile exosporium. Understanding the exosporium assembly’s molecular bases may be essential to developing new therapies against C. difficile infection. Clostridioides difficile is an obligately anaerobic, spore-forming, Gram-positive pathogenic bacterium that is considered the leading cause of nosocomial diarrhea worldwide. Recent studies have attempted to understand the biology of the outermost layer of C. difficile spores, the exosporium, which is believed to contribute to early interactions with the host. The fundamental role of the cysteine-rich proteins CdeC and CdeM has been described. However, the molecular details behind the mechanism of exosporium assembly are missing. The underlying mechanisms that govern exosporium assembly in C. difficile remain poorly studied, in part due to difficulties in obtaining pure soluble recombinant proteins of the C. difficile exosporium. In this work, we observed that CdeC was able to form organized inclusion bodies (IBs) in Escherichia coli filled with lamella-like structures separated by an interspace of 5 to 15 nm; however, CdeC expression in an E. coli strain with a more oxidative environment led to the loss of the lamella-like organization of CdeC IBs. Additionally, dithiothreitol (DTT) treatment of CdeC inclusion bodies released monomeric soluble forms of CdeC. Deletions in different portions of CdeC did not affect CdeC’s ability to aggregate and form oligomers stable under denaturation conditions but affected CdeC’s self-assembly properties. Overall, these observations have important implications in further studies elucidating the role of CdeC in the exosporium assembly of C. difficile spores. IMPORTANCE The endospore of Clostridioides difficile is the vehicle for transmission and persistence of the pathogen, and, specifically, the exosporium is the first contact between the host and the spore. The underlying mechanisms that govern exosporium assembly in C. difficile remain understudied, in part due to difficulties in obtaining pure soluble recombinant proteins of the C. difficile exosporium. Understanding the exosporium assembly’s molecular bases may be essential to developing new therapies against C. difficile infection.
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672
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McDonald NA, Fetter RD, Shen K. Assembly of synaptic active zones requires phase separation of scaffold molecules. Nature 2020; 588:454-458. [PMID: 33208945 DOI: 10.1038/s41586-020-2942-0] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 09/03/2020] [Indexed: 12/20/2022]
Abstract
The formation of synapses during neuronal development is essential for establishing neural circuits and a nervous system1. Every presynapse builds a core 'active zone' structure, where ion channels cluster and synaptic vesicles release their neurotransmitters2. Although the composition of active zones is well characterized2,3, it is unclear how active-zone proteins assemble together and recruit the machinery required for vesicle release during development. Here we find that the core active-zone scaffold proteins SYD-2 (also known as liprin-α) and ELKS-1 undergo phase separation during an early stage of synapse development, and later mature into a solid structure. We directly test the in vivo function of phase separation by using mutant SYD-2 and ELKS-1 proteins that specifically lack this activity. These mutant proteins remain enriched at synapses in Caenorhabditis elegans, but show defects in active-zone assembly and synapse function. The defects are rescued by introducing a phase-separation motif from an unrelated protein. In vitro, we reconstitute the SYD-2 and ELKS-1 liquid-phase scaffold, and find that it is competent to bind and incorporate downstream active-zone components. We find that the fluidity of SYD-2 and ELKS-1 condensates is essential for efficient mixing and incorporation of active-zone components. These data reveal that a developmental liquid phase of scaffold molecules is essential for the assembly of the synaptic active zone, before maturation into a stable final structure.
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Affiliation(s)
| | - Richard D Fetter
- Howard Hughes Medical Institute, Department of Biology, Stanford University, Stanford, CA, USA
| | - Kang Shen
- Department of Biology, Stanford University, Stanford, CA, USA. .,Howard Hughes Medical Institute, Department of Biology, Stanford University, Stanford, CA, USA.
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673
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Ahmad A, Strohbuecker S, Scotti C, Tufarelli C, Sottile V. In Silico Identification of SOX1 Post-Translational Modifications Highlights a Shared Protein Motif. Cells 2020; 9:E2471. [PMID: 33202879 PMCID: PMC7696889 DOI: 10.3390/cells9112471] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 11/10/2020] [Indexed: 12/02/2022] Open
Abstract
The transcription factor SOX1 is a key regulator of neural stem cell development, acting to keep neural stem cells (NSCs) in an undifferentiated state. Postnatal expression of Sox1 is typically confined to the central nervous system (CNS), however, its expression in non-neural tissues has recently been implicated in tumorigenesis. The mechanism through which SOX1 may exert its function is not fully understood, and studies have mainly focused on changes in SOX1 expression at a transcriptional level, while its post-translational regulation remains undetermined. To investigate this, data were extracted from different publicly available databases and analysed to search for putative SOX1 post-translational modifications (PTMs). Results were compared to PTMs associated with SOX2 in order to identify potentially key PTM motifs common to these SOXB1 proteins, and mapped on SOX1 domain structural models. This approach identified several putative acetylation, phosphorylation, glycosylation and sumoylation sites within known functional domains of SOX1. In particular, a novel SOXB1 motif (xKSExSxxP) was identified within the SOX1 protein, which was also found in other unrelated proteins, most of which were transcription factors. These results also highlighted potential phospho-sumoyl switches within this SOXB1 motif identified in SOX1, which could regulate its transcriptional activity. This analysis indicates different types of PTMs within SOX1, which may influence its regulatory role as a transcription factor, by bringing changes to its DNA binding capacities and its interactions with partner proteins. These results provide new research avenues for future investigations on the mechanisms regulating SOX1 activity, which could inform its roles in the contexts of neural stem cell development and cancer.
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Affiliation(s)
- Azaz Ahmad
- School of Medicine, The University of Nottingham, Nottingham NG7 2RD, UK; (A.A.); (S.S.)
| | - Stephanie Strohbuecker
- School of Medicine, The University of Nottingham, Nottingham NG7 2RD, UK; (A.A.); (S.S.)
| | - Claudia Scotti
- Department of Molecular Medicine, The University of Pavia, 27100 Pavia, Italy;
| | - Cristina Tufarelli
- Department of Genetics and Genome Biology/Leicester Cancer Research Centre, The University of Leicester, Leicester LE2 7LX, UK;
| | - Virginie Sottile
- School of Medicine, The University of Nottingham, Nottingham NG7 2RD, UK; (A.A.); (S.S.)
- Department of Molecular Medicine, The University of Pavia, 27100 Pavia, Italy;
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674
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Pelham JF, Dunlap JC, Hurley JM. Intrinsic disorder is an essential characteristic of components in the conserved circadian circuit. Cell Commun Signal 2020; 18:181. [PMID: 33176800 PMCID: PMC7656774 DOI: 10.1186/s12964-020-00658-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 09/06/2020] [Indexed: 12/12/2022] Open
Abstract
INTRODUCTION The circadian circuit, a roughly 24 h molecular feedback loop, or clock, is conserved from bacteria to animals and allows for enhanced organismal survival by facilitating the anticipation of the day/night cycle. With circadian regulation reportedly impacting as high as 80% of protein coding genes in higher eukaryotes, the protein-based circadian clock broadly regulates physiology and behavior. Due to the extensive interconnection between the clock and other cellular systems, chronic disruption of these molecular rhythms leads to a decrease in organismal fitness as well as an increase of disease rates in humans. Importantly, recent research has demonstrated that proteins comprising the circadian clock network display a significant amount of intrinsic disorder. MAIN BODY In this work, we focus on the extent of intrinsic disorder in the circadian clock and its potential mechanistic role in circadian timing. We highlight the conservation of disorder by quantifying the extent of computationally-predicted protein disorder in the core clock of the key eukaryotic circadian model organisms Drosophila melanogaster, Neurospora crassa, and Mus musculus. We further examine previously published work, as well as feature novel experimental evidence, demonstrating that the core negative arm circadian period drivers FREQUENCY (Neurospora crassa) and PERIOD-2 (PER2) (Mus musculus), possess biochemical characteristics of intrinsically disordered proteins. Finally, we discuss the potential contributions of the inherent biophysical principals of intrinsically disordered proteins that may explain the vital mechanistic roles they play in the clock to drive their broad evolutionary conservation in circadian timekeeping. CONCLUSION The pervasive conservation of disorder amongst the clock in the crown eukaryotes suggests that disorder is essential for optimal circadian timing from fungi to animals, providing vital homeostatic cellular maintenance and coordinating organismal physiology across phylogenetic kingdoms. Video abstract.
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Affiliation(s)
- Jacqueline F. Pelham
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY 12180 USA
| | - Jay C. Dunlap
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755 USA
| | - Jennifer M. Hurley
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY 12180 USA
- Center for Biotechnology and Interdisciplinary Sciences, Rensselaer Polytechnic Institute, Troy, NY 12018 USA
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675
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Zeke A, Dobson L, Szekeres LI, Langó T, Tusnády GE. PolarProtDb: A Database of Transmembrane and Secreted Proteins showing Apical-Basal Polarity. J Mol Biol 2020; 433:166705. [PMID: 33186585 DOI: 10.1016/j.jmb.2020.11.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/04/2020] [Accepted: 11/05/2020] [Indexed: 12/13/2022]
Abstract
Most cells in multicellular organisms are somehow asymmetric, polarized: maintaining separate membrane domains. Typical examples are the epithelial cells (apical-basal polarization), neurons (dendritic-axonal domains), or migratory cells (with a leading and a trailing edge). Here we present the most comprehensive database containing experimentally verified mammalian proteins that display polarized sorting or secretion, focusing on epithelial polarity. In addition to the source cells or tissues, homology-based inferences and transmembrane topology (if applicable) are all provided. PolarProtDb also offers a detailed interface displaying all information that may be relevant for trafficking: including post-translational modifications (glycosylations and phosphorylations), known or predicted short linear motifs conserved across orthologs, as well as potential interaction partners. Data on polarized sorting has so far been scattered across myriads of publications, hence difficult to access. This information can help researchers in several areas, such as scanning for potential entry points of viral agents like COVID-19. PolarProtDb shall be a useful resource to design future experiments as well as for comparative analyses. The database is available at http://polarprotdb.enzim.hu.
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Affiliation(s)
- András Zeke
- Membrane Protein Bioinformatics Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Magyar Tudósok körútja 2, H-1117 Budapest, Hungary
| | - László Dobson
- Membrane Protein Bioinformatics Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Magyar Tudósok körútja 2, H-1117 Budapest, Hungary; Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Levente István Szekeres
- Membrane Protein Bioinformatics Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Magyar Tudósok körútja 2, H-1117 Budapest, Hungary
| | - Tamás Langó
- Membrane Protein Bioinformatics Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Magyar Tudósok körútja 2, H-1117 Budapest, Hungary
| | - Gábor E Tusnády
- Membrane Protein Bioinformatics Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Magyar Tudósok körútja 2, H-1117 Budapest, Hungary.
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676
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Toor HG, Banerjee DI, Lipsa Rath S, Darji SA. Computational drug re-purposing targeting the spike glycoprotein of SARS-CoV-2 as an effective strategy to neutralize COVID-19. Eur J Pharmacol 2020; 890:173720. [PMID: 33160938 PMCID: PMC7644434 DOI: 10.1016/j.ejphar.2020.173720] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 10/30/2020] [Accepted: 10/30/2020] [Indexed: 01/12/2023]
Abstract
COVID-19 has intensified into a global pandemic with over a million deaths worldwide. Experimental research analyses have been implemented and executed with the sole rationale to counteract SARS-CoV-2, which has initiated potent therapeutic strategy development in coherence with computational biology validation focusing on the characterized viral drug targets signified by proteomic and genomic data. Spike glycoprotein is one of such potential drug target that promotes viral attachment to the host cellular membrane by binding to its receptor ACE-2 via its Receptor-Binding Domain (RBD). Multiple Sequence alignment and relative phylogenetic analysis revealed significant sequential disparities of SARS-CoV-2 as compared to previously encountered SARS-CoV and MERS-CoV strains. We implemented a drug re-purposing approach wherein the inhibitory efficacy of a cluster of thirty known drug candidates comprising of antivirals, antibiotics and phytochemicals (selection contingent on their present developmental status in underway clinical trials) was elucidated by subjecting them to molecular docking analyses against the spike protein RBD model (developed using homology modelling and validated using SAVES server 5.0) and the composite trimeric structures of spike glycoprotein of SARS-CoV-2. Our results indicated that Camostat, Favipiravir, Tenofovir, Raltegravir and Stavudine showed significant interactions with spike RBD of SARS-CoV-2. Proficient bioavailability coupled with no predicted in silico toxicity rendered them as prospective alternatives for designing and development of novel combinatorial therapy formulations for improving existing treatment regimes to combat COVID-19.
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Affiliation(s)
- Himanshu G Toor
- P.G. Department of Genetics, Ashok and Rita Patel Institute of Integrated Study and Research in Biotechnology and Allied Sciences (ARIBAS), Charutar Vidya Mandal University, P.O. Box No. 61, New Vallabh Vidyanagar, Vitthal Udyognagar, 388121, Anand, Gujarat, India; Sardar Patel University, Gujarat, India.
| | - Devjani I Banerjee
- Dr. Vikram Sarabhai Institute of Cell and Molecular Biology, Faculty of Science, The Maharaja Sayajirao University of Baroda, Pratapganj, Vadodara, 390002, Gujarat, India.
| | - Soumya Lipsa Rath
- National Institute of Technology, Warangal, Telangana, 506004, India.
| | - Siddhi A Darji
- Dr. Vikram Sarabhai Institute of Cell and Molecular Biology, Faculty of Science, The Maharaja Sayajirao University of Baroda, Pratapganj, Vadodara, 390002, Gujarat, India.
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677
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Hesgrove C, Boothby TC. The biology of tardigrade disordered proteins in extreme stress tolerance. Cell Commun Signal 2020; 18:178. [PMID: 33148259 PMCID: PMC7640644 DOI: 10.1186/s12964-020-00670-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 09/29/2020] [Indexed: 02/06/2023] Open
Abstract
Abstract Disordered proteins have long been known to help mediate tolerance to different abiotic stresses including freezing, osmotic stress, high temperatures, and desiccation in a diverse set of organisms. Recently, three novel families of intrinsically disordered proteins were identified in tardigrades, microscopic animals capable of surviving a battery of environmental extremes. These three families include the Cytoplasmic-, Secreted-, and Mitochondrial- Abundant Heat Soluble (CAHS, SAHS, and MAHS) proteins, which are collectively termed Tardigrade Disordered Proteins (TDPs). At the level of sequence conservation TDPs are unique to tardigrades, and beyond their high degree of disorder the CAHS, SAHS, and MAHS families do not resemble one another. All three families are either highly expressed constitutively, or significantly enriched in response to desiccation. In vivo, ex vivo, and in vitro experiments indicate functional roles for members of each TDP family in mitigating cellular perturbations induced by various abiotic stresses. What is currently lacking is a comprehensive and holistic understanding of the fundamental mechanisms by which TDPs function, and the properties of TDPs that allow them to function via those mechanisms. A quantitative and systematic approach is needed to identify precisely what cellular damage TDPs work to prevent, what sequence features are important for these functions, and how those sequence features contribute to the underlying mechanisms of protection. Such an approach will inform us not only about these fascinating proteins, but will also provide insights into how the sequence of a disordered protein can dictate its functional, structural, and dynamic properties. Video Abstract
Graphical abstract ![]()
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Affiliation(s)
- Cherie Hesgrove
- Department of Molecular Biology, University of Wyoming, Laramie, WY, 82071, USA
| | - Thomas C Boothby
- Department of Molecular Biology, University of Wyoming, Laramie, WY, 82071, USA.
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678
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Stancheva VG, Li XH, Hutchings J, Gomez-Navarro N, Santhanam B, Babu MM, Zanetti G, Miller EA. Combinatorial multivalent interactions drive cooperative assembly of the COPII coat. J Cell Biol 2020; 219:e202007135. [PMID: 32997735 PMCID: PMC7594496 DOI: 10.1083/jcb.202007135] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/20/2020] [Accepted: 08/26/2020] [Indexed: 12/31/2022] Open
Abstract
Protein secretion is initiated at the endoplasmic reticulum by the COPII coat, which self-assembles to form vesicles. Here, we examine the mechanisms by which a cargo-bound inner coat layer recruits and is organized by an outer scaffolding layer to drive local assembly of a stable structure rigid enough to enforce membrane curvature. An intrinsically disordered region in the outer coat protein, Sec31, drives binding with an inner coat layer via multiple distinct interfaces, including a newly defined charge-based interaction. These interfaces combinatorially reinforce each other, suggesting coat oligomerization is driven by the cumulative effects of multivalent interactions. The Sec31 disordered region could be replaced by evolutionarily distant sequences, suggesting plasticity in the binding interfaces. Such a multimodal assembly platform provides an explanation for how cells build a powerful yet transient scaffold to direct vesicle traffic.
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Affiliation(s)
| | - Xiao-Han Li
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Joshua Hutchings
- Institute of Structural and Molecular Biology, Birkbeck College, London, UK
| | | | | | | | - Giulia Zanetti
- Institute of Structural and Molecular Biology, Birkbeck College, London, UK
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679
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Fatalska A, Dzhindzhev NS, Dadlez M, Glover DM. Interaction interface in the C-terminal parts of centriole proteins Sas6 and Ana2. Open Biol 2020; 10:200221. [PMID: 33171067 PMCID: PMC7729032 DOI: 10.1098/rsob.200221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 10/20/2020] [Indexed: 12/14/2022] Open
Abstract
The centriole is a ninefold symmetrical structure found at the core of centrosomes and, as a basal body, at the base of cilia, whose conserved duplication is regulated by Plk4 kinase. Plk4 phosphorylates a single serine residue at the N-terminus of Ana2 to promote Ana2's loading to the site of procentriole formation. Four conserved serines in Ana2's STAN motif are then phosphorylated by Plk4, enabling Sas6 recruitment. Crystallographic data indicate that the coiled-coil domain of Ana2 forms a tetramer but the structure of full-length Ana2 has not been solved. Here, we have employed hydrogen-deuterium exchange coupled with mass spectrometry (HDX-MS) to uncover the conformational dynamics of Ana2, revealing the high flexibility of this protein with one rigid region. To determine the elusive nature of the interaction surfaces between Ana2 and Sas6, we have confirmed complex formation between the phosphomimetic form of Ana2 (Ana2-4D) and Sas6 in vitro and in vivo. Analysis of this complex by HDX-MS identifies short critical regions required for this interaction, which lie in the C-terminal parts of both proteins. Mutational studies confirmed the relevance of these regions for the Ana2-Sas6 interaction. The Sas6 site required for Ana2 binding is distinct from the site required for Sas6 to bind Gorab and Sas6 is able to bind both these protein partners simultaneously.
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Affiliation(s)
- Agnieszka Fatalska
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | | | - Michal Dadlez
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - David M. Glover
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
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680
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Muthunayake NS, Tomares DT, Childers WS, Schrader JM. Phase-separated bacterial ribonucleoprotein bodies organize mRNA decay. WILEY INTERDISCIPLINARY REVIEWS. RNA 2020; 11:e1599. [PMID: 32445438 PMCID: PMC7554086 DOI: 10.1002/wrna.1599] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 04/16/2020] [Accepted: 04/17/2020] [Indexed: 01/12/2023]
Abstract
In bacteria, mRNA decay is controlled by megadalton scale macromolecular assemblies called, "RNA degradosomes," composed of nucleases and other RNA decay associated proteins. Recent advances in bacterial cell biology have shown that RNA degradosomes can assemble into phase-separated structures, termed bacterial ribonucleoprotein bodies (BR-bodies), with many analogous properties to eukaryotic processing bodies and stress granules. This review will highlight the functional role that BR-bodies play in the mRNA decay process through its organization into a membraneless organelle in the bacterial cytoplasm. This review will also highlight the phylogenetic distribution of BR-bodies across bacterial species, which suggests that these phase-separated structures are broadly distributed across bacteria, and in evolutionarily related mitochondria and chloroplasts. This article is categorized under: RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes RNA Export and Localization > RNA Localization RNA Turnover and Surveillance > Regulation of RNA Stability.
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Affiliation(s)
| | - Dylan T Tomares
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - W Seth Childers
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Jared M Schrader
- Department of Biological Sciences, Wayne State University, Detroit, Michigan, USA
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681
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Meyer MT, Itakura AK, Patena W, Wang L, He S, Emrich-Mills T, Lau CS, Yates G, Mackinder LCM, Jonikas MC. Assembly of the algal CO 2-fixing organelle, the pyrenoid, is guided by a Rubisco-binding motif. SCIENCE ADVANCES 2020; 6:eabd2408. [PMID: 33177094 PMCID: PMC7673724 DOI: 10.1126/sciadv.abd2408] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 09/25/2020] [Indexed: 05/05/2023]
Abstract
Approximately one-third of the Earth's photosynthetic CO2 assimilation occurs in a pyrenoid, an organelle containing the CO2-fixing enzyme Rubisco. How constituent proteins are recruited to the pyrenoid and how the organelle's subcompartments-membrane tubules, a surrounding phase-separated Rubisco matrix, and a peripheral starch sheath-are held together is unknown. Using the model alga Chlamydomonas reinhardtii, we found that pyrenoid proteins share a sequence motif. We show that the motif is necessary and sufficient to target proteins to the pyrenoid and that the motif binds to Rubisco, suggesting a mechanism for targeting. The presence of the Rubisco-binding motif on proteins that localize to the tubules and on proteins that localize to the matrix-starch sheath interface suggests that the motif holds the pyrenoid's three subcompartments together. Our findings advance our understanding of pyrenoid biogenesis and illustrate how a single protein motif can underlie the architecture of a complex multilayered phase-separated organelle.
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Affiliation(s)
- Moritz T Meyer
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Alan K Itakura
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Weronika Patena
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Lianyong Wang
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Shan He
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | | | - Chun S Lau
- Department of Biology, University of York, York YO10 5DD, UK
| | - Gary Yates
- Department of Biology, University of York, York YO10 5DD, UK
| | | | - Martin C Jonikas
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
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682
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Malay AD, Suzuki T, Katashima T, Kono N, Arakawa K, Numata K. Spider silk self-assembly via modular liquid-liquid phase separation and nanofibrillation. SCIENCE ADVANCES 2020; 6:6/45/eabb6030. [PMID: 33148640 PMCID: PMC7673682 DOI: 10.1126/sciadv.abb6030] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 09/16/2020] [Indexed: 05/17/2023]
Abstract
Spider silk fiber rapidly assembles from spidroin protein in soluble state via an incompletely understood mechanism. Here, we present an integrated model for silk formation that incorporates the effects of multiple chemical and physical gradients on the different spidroin functional domains. Central to the process is liquid-liquid phase separation (LLPS) that occurs in response to multivalent anions such as phosphate, mediated by the carboxyl-terminal and repetitive domains. Acidification coupled with LLPS triggers the swift self-assembly of nanofibril networks, facilitated by dimerization of the amino-terminal domain, and leads to a liquid-to-solid phase transition. Mechanical stress applied to the fibril structures yields macroscopic fibers with hierarchical organization and enriched for β-sheet conformations. Studies using native silk gland material corroborate our findings on spidroin phase separation. Our results suggest an intriguing parallel between silk assembly and other LLPS-mediated mechanisms, such as found in intracellular membraneless organelles and protein aggregation disorders.
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Affiliation(s)
- Ali D Malay
- Biomacromolecules Research Team, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
| | - Takehiro Suzuki
- Biomolecular Characterization Unit, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Takuya Katashima
- Biomacromolecules Research Team, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Nobuaki Kono
- Institute for Advanced Biosciences, Keio University, 246-2 Mizukami, Kakuganji, Tsuruoka, Yamagata 997-0052, Japan
| | - Kazuharu Arakawa
- Institute for Advanced Biosciences, Keio University, 246-2 Mizukami, Kakuganji, Tsuruoka, Yamagata 997-0052, Japan
| | - Keiji Numata
- Biomacromolecules Research Team, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
- Department of Material Chemistry, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510, Japan
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683
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Double strand break (DSB) repair in Cyanobacteria: Understanding the process in an ancient organism. DNA Repair (Amst) 2020; 95:102942. [DOI: 10.1016/j.dnarep.2020.102942] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/19/2020] [Accepted: 07/26/2020] [Indexed: 02/07/2023]
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684
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Comer S, Nagy Z, Bolado A, von Kriegsheim A, Gambaryan S, Walter U, Pagel O, Zahedi RP, Jurk K, Smolenski A. The RhoA regulators Myo9b and GEF-H1 are targets of cyclic nucleotide-dependent kinases in platelets. J Thromb Haemost 2020; 18:3002-3012. [PMID: 32692911 DOI: 10.1111/jth.15028] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 06/15/2020] [Accepted: 07/13/2020] [Indexed: 12/18/2022]
Abstract
BACKGROUND Circulating platelets are maintained in an inactive state by the endothelial lining of the vasculature. Endothelium-derived prostacyclin and nitric oxide stimulate cAMP- and cGMP-dependent kinases, PKA and PKG, to inhibit platelets. PKA and PKG effects include the inhibition of the GTPase RhoA, which has been suggested to involve the direct phosphorylation of RhoA on serine 188. OBJECTIVES We wanted to confirm RhoA S188 phosphorylation by cyclic nucleotide-dependent kinases and to identify possible alternative mechanisms of RhoA regulation in platelets. METHODS Phosphoproteomics data of human platelets were used to identify candidate PKA and PKG substrates. Phosphorylation of individual proteins was studied by Western blotting and Phos-tag gel electrophoresis in human platelets and transfected HEK293T cells. Pull-down assays were performed to analyze protein interaction and function. RESULTS Our data indicate that RhoA is not phosphorylated by PKA in platelets. Instead, we provide evidence that cyclic nucleotide effects are mediated through the phosphorylation of the RhoA-specific GTPase-activating protein Myo9b and the guanine nucleotide exchange factor GEF-H1. We identify Myo9b S1354 and guanine nucleotide exchange factor-H1 (GEF-H1) S886 as PKA and PKG phosphorylation sites. Myo9b S1354 phosphorylation enhances its GTPase activating protein function leading to reduced RhoA-GTP levels. GEF-H1 S886 phosphorylation stimulates binding of 14-3-3β and has been shown to inhibit GEF function by facilitating binding of GEF-H1 to microtubules. Microtubule disruption increases RhoA-GTP levels confirming the importance of GEF-H1 in platelets. CONCLUSION Phosphorylation of RhoA regulatory proteins Myo9b and GEF-H1, but not RhoA itself, is involved in cyclic nucleotide-mediated control of RhoA in human platelets.
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Affiliation(s)
- Shane Comer
- UCD School of Medicine and Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
- Irish Centre for Vascular Biology, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Zoltan Nagy
- UCD School of Medicine and Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
- Institute of Experimental Biomedicine, University Hospital and Rudolf Virchow Center, University of Würzburg, Würzburg, Germany
| | - Alfonso Bolado
- Cancer Research UK Edinburgh Centre, University of Edinburgh, Edinburgh, UK
| | | | - Stepan Gambaryan
- Sechenov Institute for Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Ulrich Walter
- Center for Thrombosis and Hemostasis, University Medical Center Mainz, Mainz, Germany
| | - Oliver Pagel
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., Dortmund, Germany
| | - René P Zahedi
- Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., Dortmund, Germany
- Segal Cancer Proteomics Centre, Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, QC, Canada
| | - Kerstin Jurk
- Center for Thrombosis and Hemostasis, University Medical Center Mainz, Mainz, Germany
| | - Albert Smolenski
- UCD School of Medicine and Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
- Irish Centre for Vascular Biology, Royal College of Surgeons in Ireland, Dublin 2, Ireland
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685
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Tomaszewski T, DeVries RS, Dong M, Bhatia G, Norsworthy MD, Zheng X, Caetano-Anollés G. New Pathways of Mutational Change in SARS-CoV-2 Proteomes Involve Regions of Intrinsic Disorder Important for Virus Replication and Release. Evol Bioinform Online 2020; 16:1176934320965149. [PMID: 33149541 PMCID: PMC7586267 DOI: 10.1177/1176934320965149] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 09/16/2020] [Indexed: 12/21/2022] Open
Abstract
The massive worldwide spread of the SARS-CoV-2 virus is fueling the COVID-19 pandemic. Since the first whole-genome sequence was published in January 2020, a growing database of tens of thousands of viral genomes has been constructed. This offers opportunities to study pathways of molecular change in the expanding viral population that can help identify molecular culprits of virulence and virus spread. Here we investigate the genomic accumulation of mutations at various time points of the early pandemic to identify changes in mutationally highly active genomic regions that are occurring worldwide. We used the Wuhan NC_045512.2 sequence as a reference and sampled 15 342 indexed sequences from GISAID, translating them into proteins and grouping them by month of deposition. The per-position amino acid frequencies and Shannon entropies of the coding sequences were calculated for each month, and a map of intrinsic disorder regions and binding sites was generated. The analysis revealed dominant variants, most of which were located in loop regions and on the surface of the proteins. Mutation entropy decreased between March and April of 2020 after steady increases at several sites, including the D614G mutation site of the spike (S) protein that was previously found associated with higher case fatality rates and at sites of the NSP12 polymerase and the NSP13 helicase proteins. Notable expanding mutations include R203K and G204R of the nucleocapsid (N) protein inter-domain linker region and G251V of the viroporin encoded by ORF3a between March and April. The regions spanning these mutations exhibited significant intrinsic disorder, which was enhanced and decreased by the N-protein and viroporin 3a protein mutations, respectively. These results predict an ongoing mutational shift from the spike and replication complex to other regions, especially to encoded molecules known to represent major β-interferon antagonists. The study provides valuable information for therapeutics and vaccine design, as well as insight into mutation tendencies that could facilitate preventive control.
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Affiliation(s)
- Tre Tomaszewski
- Department of Information Sciences, University of Illinois, Urbana, IL, USA
| | - Ryan S DeVries
- Department of Information Sciences, University of Illinois, Urbana, IL, USA
| | - Mengyi Dong
- Department of Food Science & Human Nutrition, University of Illinois, Urbana, IL, USA
| | - Gitanshu Bhatia
- Department of Agricultural & Biological Engineering, University of Illinois, Urbana, IL, USA
| | | | - Xuying Zheng
- Department of Crop Sciences, University of Illinois, Urbana, IL, USA
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686
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Ilik İA, Malszycki M, Lübke AK, Schade C, Meierhofer D, Aktaş T. SON and SRRM2 are essential for nuclear speckle formation. eLife 2020; 9:60579. [PMID: 33095160 PMCID: PMC7671692 DOI: 10.7554/elife.60579] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 10/20/2020] [Indexed: 12/17/2022] Open
Abstract
Nuclear speckles (NS) are among the most prominent biomolecular condensates. Despite their prevalence, research on the function of NS is virtually restricted to colocalization analyses, since an organizing core, without which NS cannot form, remains unidentified. The monoclonal antibody SC35, raised against a spliceosomal extract, is frequently used to mark NS. Unexpectedly, we found that this antibody was mischaracterized and the main target of SC35 mAb is SRRM2, a spliceosome-associated protein that sharply localizes to NS. Here we show that, the core of NS is likely formed by SON and SRRM2, since depletion of SON leads only to a partial disassembly of NS, while co-depletion of SON and SRRM2 or depletion of SON in a cell-line where intrinsically disordered regions (IDRs) of SRRM2 are genetically deleted, leads to a near-complete dissolution of NS. This work, therefore, paves the way to study the role of NS under diverse physiological and stress conditions. Most cells store their genetic material inside a compartment called the nucleus, which helps to separate DNA from other molecules in the cell. Inside the nucleus, DNA is tightly packed together with proteins that can read the cell’s genetic code and convert into the RNA molecules needed to build proteins. However, the contents of the nucleus are not randomly arranged, and these proteins are often clustered into specialized areas where they perform their designated roles. One of the first nuclear territories to be identified were granular looking structures named Nuclear Speckles (or NS for short), which are thought to help process RNA before it leaves the nucleus. Structures like NS often contain a number of different factors held together by a core group of proteins known as a scaffold. Although NS were discovered over a century ago, little is known about their scaffold proteins, making it difficult to understand the precise role of these speckles. Typically, researchers visualize NS using a substance called SC35 which targets specific sites in these structures. However, it was unclear which parts of the NS this marker binds to. To answer this question, Ilik et al. studied NS in human cells grown in the lab. The analysis revealed that SC35 attaches to certain parts of a large, flexible protein called SRRM2. Ilik et al. discovered that although the structure and sequence of SRMM2 varies between different animal species, a small region of this protein remained unchanged throughout evolution. Studying the evolutionary history of SRRM2 led to the identification of another protein with similar properties called SON. Ilik et al. found that depleting SON and SRRM2 from human cells caused other proteins associated with the NS to diffuse away from their territories and become dispersed within the nucleus. This suggests that SRMM2 and SON make up the scaffold that holds the proteins in NS together. Nuclear speckles have been associated with certain viral infections, and seem to help prevent the onset of diseases such as Huntington’s and spinocerebellar ataxia. These newly discovered core proteins could therefore further our understanding of the role NS play in disease.
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Affiliation(s)
| | - Michal Malszycki
- Max Planck Institute for Molecular Genetics, Berlin, Germany.,Freie Universität Berlin, Berlin, Germany
| | - Anna Katharina Lübke
- Max Planck Institute for Molecular Genetics, Berlin, Germany.,Freie Universität Berlin, Berlin, Germany
| | - Claudia Schade
- Max Planck Institute for Molecular Genetics, Berlin, Germany
| | | | - Tuğçe Aktaş
- Max Planck Institute for Molecular Genetics, Berlin, Germany
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687
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Xiang Y, Zou Q, Zhao L. VPTMdb: a viral posttranslational modification database. Brief Bioinform 2020; 22:5935500. [PMID: 33094321 DOI: 10.1093/bib/bbaa251] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/03/2020] [Accepted: 09/07/2020] [Indexed: 11/14/2022] Open
Abstract
In viruses, posttranslational modifications (PTMs) are essential for their life cycle. Recognizing viral PTMs is very important for a better understanding of the mechanism of viral infections and finding potential drug targets. However, few studies have investigated the roles of viral PTMs in virus-human interactions using comprehensive viral PTM datasets. To fill this gap, we developed the first comprehensive viral posttranslational modification database (VPTMdb) for collecting systematic information of PTMs in human viruses and infected host cells. The VPTMdb contains 1240 unique viral PTM sites with 8 modification types from 43 viruses (818 experimentally verified PTM sites manually extracted from 150 publications and 422 PTMs extracted from SwissProt) as well as 13 650 infected cells' PTMs extracted from seven global proteomics experiments in six human viruses. The investigation of viral PTM sequences motifs showed that most viral PTMs have the consensus motifs with human proteins in phosphorylation and five cellular kinase families phosphorylate more than 10 viral species. The analysis of protein disordered regions presented that more than 50% glycosylation sites of double-strand DNA viruses are in the disordered regions, whereas single-strand RNA and retroviruses prefer ordered regions. Domain-domain interaction analysis indicating potential roles of viral PTMs play in infections. The findings should make an important contribution to the field of virus-human interaction. Moreover, we created a novel sequence-based classifier named VPTMpre to help users predict viral protein phosphorylation sites. VPTMdb online web server (http://vptmdb.com:8787/VPTMdb/) was implemented for users to download viral PTM data and predict phosphorylation sites of interest.
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Affiliation(s)
- Yujia Xiang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences
| | - Quan Zou
- University of Electronic Science and Technology of China
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688
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Kumar N, Sood D, Chandra R. Vaccine Formulation and Optimization for Human Herpes Virus-5 through an Immunoinformatics Framework. ACS Pharmacol Transl Sci 2020; 3:1318-1329. [PMID: 33344905 DOI: 10.1021/acsptsci.0c00139] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Indexed: 12/12/2022]
Abstract
In the current situation, the importance of vaccines for viral diseases has become the need of the hour. The scientific community in the field of virology has taken it upon themselves to develop vaccines for viral infections before an epidemic or pandemic situation arises. Human herpes virus-5 is an emerging situation that has alarming cases with major health concerns, including congenital impairments and infections leading to cancer states. Vaccination is the route most likely to succeed in the battleground with viral infections and consequences. Hence in the present manuscript, we have formulated the multiepitope subunit vaccine and optimized it with the advanced computational immunological framework. As a result, we report the subunit vaccine for HHV-5, comprised of promiscuous cytotoxic T-lymphocytes epitopes, helper T-lymphocytes, and B-cell epitopes engineered with putative adjuvants to ensure the strong immune response. The formulated subunit vaccine depicted high antigenicity and immunogenicity along with sustainable physicochemical characteristics. Molecular dynamics simulation analyses revealed the strong binding of the vaccine with MHC receptors (MHC-1 and MHC-2) and the virus progression specific membrane receptor TLR2 for a 100 ns MD simulation run. The interacting trajectory analysis of the vaccine showed stable binding with minimal deviations through RMSD, RMSF, and secondary structure confinement plot analyses for a long span of 100 ns. Interestingly, the vaccine showed robust immune response statistics for a prolonged time with evoking T-cell and B-cell populations with other vital players of the immune system, through the machine learning-based immune simulation approach. This study paved the way to a multiepitope vaccine for HHV-5 employing the immunoinformatics networks.
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Affiliation(s)
- Neeraj Kumar
- Department of Chemistry, University of Delhi, Delhi 110007, India
| | - Damini Sood
- Department of Chemistry, University of Delhi, Delhi 110007, India
| | - Ramesh Chandra
- Department of Chemistry, University of Delhi, Delhi 110007, India
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689
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Sarkadi B, Homolya L, Hegedűs T. The ABCG2/BCRP transporter and its variants - from structure to pathology. FEBS Lett 2020; 594:4012-4034. [PMID: 33015850 DOI: 10.1002/1873-3468.13947] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/27/2020] [Accepted: 09/21/2020] [Indexed: 12/13/2022]
Abstract
The ABCG2 protein has a key role in the transport of a wide range of structurally dissimilar endo- and xenobiotics in the human body, especially in the tissue barriers and the metabolizing or secreting organs. The human ABCG2 gene harbors a high number of polymorphisms and mutations, which may significantly modulate its expression and function. Recent high-resolution structural data, complemented with molecular dynamic simulations, may significantly help to understand intramolecular movements and substrate handling, as well as the effects of mutations on the membrane transporter function of ABCG2. As reviewed here, structural alterations may result not only in direct alterations in drug binding and transporter activity, but also in improper folding or problems in the carefully regulated process of trafficking, including vesicular transport, endocytosis, recycling, and degradation. Here, we also review the clinical importance of altered ABCG2 expression and function in general drug metabolism, cancer multidrug resistance, and impaired uric acid excretion, leading to gout.
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Affiliation(s)
- Balázs Sarkadi
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary.,Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
| | - László Homolya
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Tamás Hegedűs
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
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690
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Li TM, Ren J, Husmann D, Coan JP, Gozani O, Chua KF. Multivalent tumor suppressor adenomatous polyposis coli promotes Axin biomolecular condensate formation and efficient β-catenin degradation. Sci Rep 2020; 10:17425. [PMID: 33060621 PMCID: PMC7562749 DOI: 10.1038/s41598-020-74080-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 09/23/2020] [Indexed: 11/16/2022] Open
Abstract
The tumor suppressor adenomatous polyposis coli (APC) is frequently mutated in colorectal cancers. APC and Axin are core components of a destruction complex that scaffolds GSK3β and CK1 to earmark β-catenin for proteosomal degradation. Disruption of APC results in pathologic stabilization of β-catenin and oncogenesis. However, the molecular mechanism by which APC promotes β-catenin degradation is unclear. Here, we find that the intrinsically disordered region (IDR) of APC, which contains multiple β-catenin and Axin interacting sites, undergoes liquid–liquid phase separation (LLPS) in vitro. Expression of the APC IDR in colorectal cells promotes Axin puncta formation and β-catenin degradation. Our results support the model that multivalent interactions between APC and Axin drives the β-catenin destruction complex to form biomolecular condensates in cells, which concentrate key components to achieve high efficient degradation of β-catenin.
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Affiliation(s)
- Tie-Mei Li
- Department of Medicine, Stanford University School of Medicine, Stanford, CA, 94305, USA. .,Department of Biology, Stanford University, Stanford, CA, 94305, USA. .,Medical Research Council Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK.
| | - Jing Ren
- Medical Research Council Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Dylan Husmann
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - John P Coan
- Department of Medicine, Stanford University School of Medicine, Stanford, CA, 94305, USA.,Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - Or Gozani
- Department of Biology, Stanford University, Stanford, CA, 94305, USA.
| | - Katrin F Chua
- Department of Medicine, Stanford University School of Medicine, Stanford, CA, 94305, USA. .,Education, and Clinical Center, Geriatric Research, Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, 94304, USA.
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691
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Quaglia F, Hatos A, Piovesan D, Tosatto SCE. Exploring Manually Curated Annotations of Intrinsically Disordered Proteins with DisProt. ACTA ACUST UNITED AC 2020; 72:e107. [PMID: 33017101 DOI: 10.1002/cpbi.107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
DisProt is the major repository of manually curated data for intrinsically disordered proteins collected from the literature. Although lacking a stable tertiary structure under physiological conditions, intrinsically disordered proteins carry out a plethora of biological functions, some of them directly arising from their flexible nature. A growing number of scientific studies have been published during the last few decades in an effort to shed light on their unstructured state, their binding modes, and their functions. DisProt makes use of a team of expert biocurators to provide up-to-date annotations of intrinsically disordered proteins from the literature, making them available to the scientific community. Here we present a comprehensive description on how to use DisProt in different contexts and provide a detailed explanation of how to explore and interpret manually curated annotations of intrinsically disordered proteins. We describe how to search DisProt annotations, using both the web interface and the API for programmatic access. Finally, we explain how to visualize and interpret a DisProt entry, p53, a widely studied protein characterized by the presence of unstructured N-terminal and C-terminal regions. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Performing a search in DisProt Support Protocol 1: Downloading options Support Protocol 2: Programmatic access with DisProt REST API Basic Protocol 2: Visualizing and interpreting DisProt entries: the p53 use case Basic Protocol 3: Providing feedback and submitting new intrinsic disorder-related data.
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Affiliation(s)
- Federica Quaglia
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - András Hatos
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Damiano Piovesan
- Department of Biomedical Sciences, University of Padova, Padova, Italy
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692
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Evolutionary Study of Disorder in Protein Sequences. Biomolecules 2020; 10:biom10101413. [PMID: 33036302 PMCID: PMC7650552 DOI: 10.3390/biom10101413] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 09/29/2020] [Accepted: 10/03/2020] [Indexed: 12/14/2022] Open
Abstract
Intrinsically disordered proteins (IDPs) contain regions lacking intrinsic globular structure (intrinsically disordered regions, IDRs). IDPs are present across the tree of life, with great variability of IDR type and frequency even between closely related taxa. To investigate the function of IDRs, we evaluated and compared the distribution of disorder content in 10,695 reference proteomes, confirming its high variability and finding certain correlation along the Euteleostomi (bony vertebrates) lineage to number of cell types. We used the comparison of orthologs to study the function of disorder related to increase in cell types, observing that multiple interacting subunits of protein complexes might gain IDRs in evolution, thus stressing the function of IDRs in modulating protein-protein interactions, particularly in the cell nucleus. Interestingly, the conservation of local compositional biases of IDPs follows residue-type specific patterns, with E- and K-rich regions being evolutionarily stable and Q- and A-rich regions being more dynamic. We provide a framework for targeted evolutionary studies of the emergence of IDRs. We believe that, given the large variability of IDR distributions in different species, studies using this evolutionary perspective are required.
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693
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Rodriguez JM, Pozo F, di Domenico T, Vazquez J, Tress ML. An analysis of tissue-specific alternative splicing at the protein level. PLoS Comput Biol 2020; 16:e1008287. [PMID: 33017396 PMCID: PMC7561204 DOI: 10.1371/journal.pcbi.1008287] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 10/15/2020] [Accepted: 08/25/2020] [Indexed: 01/09/2023] Open
Abstract
The role of alternative splicing is one of the great unanswered questions in cellular biology. There is strong evidence for alternative splicing at the transcript level, and transcriptomics experiments show that many splice events are tissue specific. It has been suggested that alternative splicing evolved in order to remodel tissue-specific protein-protein networks. Here we investigated the evidence for tissue-specific splicing among splice isoforms detected in a large-scale proteomics analysis. Although the data supporting alternative splicing is limited at the protein level, clear patterns emerged among the small numbers of alternative splice events that we could detect in the proteomics data. More than a third of these splice events were tissue-specific and most were ancient: over 95% of splice events that were tissue-specific in both proteomics and RNAseq analyses evolved prior to the ancestors of lobe-finned fish, at least 400 million years ago. By way of contrast, three in four alternative exons in the human gene set arose in the primate lineage, so our results cannot be extrapolated to the whole genome. Tissue-specific alternative protein forms in the proteomics analysis were particularly abundant in nervous and muscle tissues and their genes had roles related to the cytoskeleton and either the structure of muscle fibres or cell-cell connections. Our results suggest that this conserved tissue-specific alternative splicing may have played a role in the development of the vertebrate brain and heart. We manually curated a set of 255 splice events detected in a large-scale tissue-based proteomics experiment and found that more than a third had evidence of significant tissue-specific differences. Events that were significantly tissue-specific at the protein level were highly conserved; almost 75% evolved over 400 million years ago. The tissues in which we found most evidence for tissue-specific splicing were nervous tissues and cardiac tissues. Genes with tissue-specific events in these two tissues had functions related to important cellular structures in brain and heart tissues. These splice events may have been essential for the development of vertebrate heart and muscle. However, our data set may not be representative of alternative exons as a whole. We found that most tissue specific splicing was strongly conserved, but just 5% of annotated alternative exons in the human gene set are ancient. More than three quarters of alternative exons are primate-derived. Although the analysis does not provide a definitive answer to the question of the functional role of alternative splicing, our results do indicate that alternative splice variants may have played a significant part in the evolution of brain and heart tissues in vertebrates.
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Affiliation(s)
- Jose Manuel Rodriguez
- Cardiovascular Proteomics Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Calle Melchor Fernandez, Madrid, Spain
| | - Fernando Pozo
- Bioinformatics Unit, Spanish National Cancer Research Centre (CNIO), Calle Melchor Fernandez, Madrid, Spain
| | - Tomas di Domenico
- Bioinformatics Unit, Spanish National Cancer Research Centre (CNIO), Calle Melchor Fernandez, Madrid, Spain
| | - Jesus Vazquez
- Cardiovascular Proteomics Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Calle Melchor Fernandez, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
| | - Michael L. Tress
- Bioinformatics Unit, Spanish National Cancer Research Centre (CNIO), Calle Melchor Fernandez, Madrid, Spain
- * E-mail:
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694
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Lang A, Goradia N, Wikman H, Werner S, Wilmanns M, Ohlenschläger O. 1H, 13C, and 15N backbone assignments of the C-terminal region of the human retinoic acid-induced protein 2. BIOMOLECULAR NMR ASSIGNMENTS 2020; 14:271-275. [PMID: 32557393 DOI: 10.1007/s12104-020-09960-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 06/10/2020] [Indexed: 06/11/2023]
Abstract
Retinoic acid-induced protein 2 is a human protein of 530 residues encoded by the RAI2 gene (Q9Y5P3; RAI2_HUMAN). RAI2 is a novel tumor suppressor protein whose depletion in breast cancer cell lines results in the downregulation of several genes associated with differentiation along with increased invasiveness and aggressive tumor phenotype of the cells. The role of the protein is specified to be a transcriptional regulator that promotes chromosomal stability and hence controls the expression of several regulators of cancer and metastasis. Structurally, RAI2 remains an unknown entity and, hence, to obtain a detailed view on the structure function relationship we report the 1H, 13C, and 15N resonance assignments for the backbone and side chain nuclei of the C-terminal region (a.a. 303-451 of UniProt Q9Y5P3) of RAI2.
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Affiliation(s)
- Andras Lang
- Leibniz Institute on Aging - Fritz Lipmann Institute, Beutenbergstr. 11, 07745, Jena, Germany
| | - Nishit Goradia
- European Molecular Biology Laboratory, Hamburg Unit, Notkestrasse 85, 22607, Hamburg, Germany
| | - Harriet Wikman
- Institute of Tumor Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Stefan Werner
- Institute of Tumor Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Matthias Wilmanns
- European Molecular Biology Laboratory, Hamburg Unit, Notkestrasse 85, 22607, Hamburg, Germany
- University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Oliver Ohlenschläger
- Leibniz Institute on Aging - Fritz Lipmann Institute, Beutenbergstr. 11, 07745, Jena, Germany.
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695
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Lang A, Kumar A, Jirschitzka J, Bordusa F, Ohlenschläger O, Wiedemann C. 1H, 13C, and 15N Backbone assignments of the human brain and acute leukemia cytoplasmic (BAALC) protein. BIOMOLECULAR NMR ASSIGNMENTS 2020; 14:163-168. [PMID: 32240523 PMCID: PMC7462906 DOI: 10.1007/s12104-020-09938-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 03/26/2020] [Indexed: 06/11/2023]
Abstract
The brain and acute leukemia cytoplasmic (BAALC; UniProt entry Q8WXS3) is a 180-residue-long human protein having six known isoforms. BAALC is expressed in either hematopoietic or neuroectodermal cells and its specific function is still to be revealed. However, as a presumably membrane-anchored protein at the cytoplasmic side it is speculated that BAALC exerts its function at the postsynaptic densities of certain neurons and might play a role in developing cytogenetically normal acute myeloid leukemia (CN-AML) when it is highly overexpressed by myeloid or lymphoid progenitor cells. In order to better understand the physiological role of BAALC and to provide the basis for a further molecular characterization of BAALC, we report here the 1H, 13C, and 15N resonance assignments for the backbone nuclei of its longest hematopoietic isoform (isoform 1). In addition, we present a 1HN and 15NH chemical shift comparison of BAALC with its shortest, neuroectodermal isoform (isoform 6) which shows only minor changes in the 1H and 15N chemical shifts.
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Affiliation(s)
- Andras Lang
- Leibniz Institute on Aging - Fritz Lipmann Institute, Beutenbergstr. 11, 07745, Jena, Germany
| | - Amit Kumar
- Leibniz Institute on Aging - Fritz Lipmann Institute, Beutenbergstr. 11, 07745, Jena, Germany
| | - Jan Jirschitzka
- Department of Chemistry, Institute of Biochemistry, University of Cologne, Zülpicher Str. 47, 50674, Cologne, Germany
| | - Frank Bordusa
- Institute of Biochemistry and Biotechnology, Charles Tanford Protein Center, Martin-Luther-University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle, Germany
| | - Oliver Ohlenschläger
- Leibniz Institute on Aging - Fritz Lipmann Institute, Beutenbergstr. 11, 07745, Jena, Germany
| | - Christoph Wiedemann
- Institute of Biochemistry and Biotechnology, Charles Tanford Protein Center, Martin-Luther-University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle, Germany.
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696
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Risser F, Collin S, Dos Santos-Morais R, Gruez A, Chagot B, Weissman KJ. Towards improved understanding of intersubunit interactions in modular polyketide biosynthesis: Docking in the enacyloxin IIa polyketide synthase. J Struct Biol 2020; 212:107581. [DOI: 10.1016/j.jsb.2020.107581] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 07/14/2020] [Accepted: 07/16/2020] [Indexed: 12/26/2022]
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697
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Karaaslan ES, Wang N, Faiß N, Liang Y, Montgomery SA, Laubinger S, Berendzen KW, Berger F, Breuninger H, Liu C. Marchantia TCP transcription factor activity correlates with three-dimensional chromatin structure. NATURE PLANTS 2020; 6:1250-1261. [PMID: 32895530 DOI: 10.1038/s41477-020-00766-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 08/07/2020] [Indexed: 05/04/2023]
Abstract
Information in the genome is not only encoded within sequence or epigenetic modifications, but is also found in how it folds in three-dimensional space. The formation of self-interacting genomic regions, named topologically associated domains (TADs), is known as a key feature of genome organization beyond the nucleosomal level. However, our understanding of the formation and function of TADs in plants is extremely limited. Here we show that the genome of Marchantia polymorpha, a member of a basal land plant lineage, exhibits TADs with epigenetic features similar to those of higher plants. By analysing various epigenetic marks across Marchantia TADs, we find that these regions generally represent interstitial heterochromatin and their borders are enriched with Marchantia transcription factor TCP1. We also identify a type of TAD that we name 'TCP1-rich TAD', in which genomic regions are highly accessible and are densely bound by TCP1 proteins. Transcription of TCP1 target genes differs on the basis gene location, and those in TCP1-rich TADs clearly show a lower expression level. In tcp1 mutant lines, neither TCP1-bound TAD borders nor TCP1-rich TADs display drastically altered chromatin organization patterns, suggesting that, in Marchantia, TCP1 is dispensable for TAD formation. However, we find that in tcp1 mutants, genes residing in TCP1-rich TADs have a greater extent of expression fold change as opposed to genes that do not belong to these TADs. Our results suggest that, besides standing as spatial chromatin-packing modules, plant TADs function as nuclear microcompartments associated with transcription factor activities.
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Affiliation(s)
| | - Nan Wang
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
| | - Natalie Faiß
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
| | - Yuyu Liang
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
| | - Sean A Montgomery
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), Vienna, Austria
| | - Sascha Laubinger
- Institute for Biology and Environmental Science, University of Oldenburg, Oldenburg, Germany
| | | | - Frédéric Berger
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), Vienna, Austria
| | - Holger Breuninger
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany
| | - Chang Liu
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, Tübingen, Germany.
- Institute of Biology, University of Hohenheim, Stuttgart, Germany.
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698
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Jarnot P, Ziemska-Legiecka J, Dobson L, Merski M, Mier P, Andrade-Navarro MA, Hancock JM, Dosztányi Z, Paladin L, Necci M, Piovesan D, Tosatto SCE, Promponas VJ, Grynberg M, Gruca A. PlaToLoCo: the first web meta-server for visualization and annotation of low complexity regions in proteins. Nucleic Acids Res 2020; 48:W77-W84. [PMID: 32421769 PMCID: PMC7319588 DOI: 10.1093/nar/gkaa339] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 04/08/2020] [Accepted: 05/01/2020] [Indexed: 12/25/2022] Open
Abstract
Low complexity regions (LCRs) in protein sequences are characterized by a less diverse amino acid composition compared to typically observed sequence diversity. Recent studies have shown that LCRs may co-occur with intrinsically disordered regions, are highly conserved in many organisms, and often play important roles in protein functions and in diseases. In previous decades, several methods have been developed to identify regions with LCRs or amino acid bias, but most of them as stand-alone applications and currently there is no web-based tool which allows users to explore LCRs in protein sequences with additional functional annotations. We aim to fill this gap by providing PlaToLoCo - PLAtform of TOols for LOw COmplexity-a meta-server that integrates and collects the output of five different state-of-the-art tools for discovering LCRs and provides functional annotations such as domain detection, transmembrane segment prediction, and calculation of amino acid frequencies. In addition, the union or intersection of the results of the search on a query sequence can be obtained. By developing the PlaToLoCo meta-server, we provide the community with a fast and easily accessible tool for the analysis of LCRs with additional information included to aid the interpretation of the results. The PlaToLoCo platform is available at: http://platoloco.aei.polsl.pl/.
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Affiliation(s)
- Patryk Jarnot
- Department of Computer Networks and Systems, Silesian University of Technology, Akademicka 16, 44-100 Gliwice, Poland
| | | | - Laszlo Dobson
- Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter u. 50/A, 1083 Budapest, Hungary.,Research Centre for Natural Sciences, Magyar Tudósok Körútja 2, 1117 Budapest, Hungary
| | - Matthew Merski
- Structural Biology Group, Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Pablo Mier
- Faculty of Biology, Johannes Gutenberg University Mainz, Hans-Dieter-Hüsch-Weg 15, 55128 Mainz, Germany
| | - Miguel A Andrade-Navarro
- Faculty of Biology, Johannes Gutenberg University Mainz, Hans-Dieter-Hüsch-Weg 15, 55128 Mainz, Germany
| | - John M Hancock
- ELIXIR, Wellcome Genome Campus, Hinxton, Cambridgeshire CB10 1SD, UK
| | - Zsuzsanna Dosztányi
- Department of Biochemistry, ELTE Eötvös LorándUniversity, Budapest, Pázmány Péter stny 1/c 1117, Budapest, Hungary
| | - Lisanna Paladin
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy
| | - Marco Necci
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy
| | - Damiano Piovesan
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy
| | - Silvio C E Tosatto
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy
| | - Vasilis J Promponas
- Bioinformatics Research Laboratory, Department of Biological Sciences, University of Cyprus, P.O. Box 20537, Nicosia, CY 1678, Cyprus
| | - Marcin Grynberg
- Institute of Biochemistry and Biophysics PAS, Pawinskiego 5A, 02-106 Warsaw, Poland
| | - Aleksandra Gruca
- Department of Computer Networks and Systems, Silesian University of Technology, Akademicka 16, 44-100 Gliwice, Poland
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699
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A Calcium Sensor Discovered in Bluetongue Virus Nonstructural Protein 2 Is Critical for Virus Replication. J Virol 2020; 94:JVI.01099-20. [PMID: 32759321 PMCID: PMC7527055 DOI: 10.1128/jvi.01099-20] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 07/29/2020] [Indexed: 12/20/2022] Open
Abstract
After entering the host cells, viruses use cellular host factors to ensure a successful virus replication process. For replication in infected cells, members of the Reoviridae family form inclusion body-like structures known as viral inclusion bodies (VIB) or viral factories. Bluetongue virus (BTV) forms VIBs in infected cells through nonstructural protein 2 (NS2), a phosphoprotein. An important regulatory factor critical for VIB formation is phosphorylation of NS2. In our study, we discovered a characteristic calcium-binding EF-hand-like motif in NS2 and found that the calcium binding preferentially affects phosphorylation level of the NS2 and has a role in regulating VIB assembly. Many viruses use specific viral proteins to bind calcium ions (Ca2+) for stability or to modify host cell pathways; however, to date, no Ca2+ binding protein has been reported in bluetongue virus (BTV), the causative agent of bluetongue disease in livestock. Here, using a comprehensive bioinformatics screening, we identified a putative EF-hand-like Ca2+ binding motif in the carboxyl terminal region of BTV nonstructural phosphoprotein 2 (NS2). Subsequently, using a recombinant NS2, we demonstrated that NS2 binds Ca2+ efficiently and that Ca2+ binding was perturbed when the Asp and Glu residues in the motif were substituted by alanine. Using circular dichroism analysis, we found that Ca2+ binding by NS2 triggered a helix-to-coil secondary structure transition. Further, cryo-electron microscopy in the presence of Ca2+ revealed that NS2 forms helical oligomers which, when aligned with the N-terminal domain crystal structure, suggest an N-terminal domain that wraps around the C-terminal domain in the oligomer. Further, an in vitro kinase assay demonstrated that Ca2+ enhanced the phosphorylation of NS2 significantly. Importantly, mutations introduced at the Ca2+ binding site in the viral genome by reverse genetics failed to allow recovery of viable virus, and the NS2 phosphorylation level and assembly of viral inclusion bodies (VIBs) were reduced. Together, our data suggest that NS2 is a dedicated Ca2+ binding protein and that calcium sensing acts as a trigger for VIB assembly, which in turn facilitates virus replication and assembly. IMPORTANCE After entering the host cells, viruses use cellular host factors to ensure a successful virus replication process. For replication in infected cells, members of the Reoviridae family form inclusion body-like structures known as viral inclusion bodies (VIB) or viral factories. Bluetongue virus (BTV) forms VIBs in infected cells through nonstructural protein 2 (NS2), a phosphoprotein. An important regulatory factor critical for VIB formation is phosphorylation of NS2. In our study, we discovered a characteristic calcium-binding EF-hand-like motif in NS2 and found that the calcium binding preferentially affects phosphorylation level of the NS2 and has a role in regulating VIB assembly.
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700
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Distinct RNA N-demethylation pathways catalyzed by nonheme iron ALKBH5 and FTO enzymes enable regulation of formaldehyde release rates. Proc Natl Acad Sci U S A 2020; 117:25284-25292. [PMID: 32989163 DOI: 10.1073/pnas.2007349117] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The AlkB family of nonheme Fe(II)/2-oxoglutarate-dependent oxygenases are essential regulators of RNA epigenetics by serving as erasers of one-carbon marks on RNA with release of formaldehyde (FA). Two major human AlkB family members, FTO and ALKBH5, both act as oxidative demethylases of N6-methyladenosine (m6A) but furnish different major products, N6-hydroxymethyladenosine (hm6A) and adenosine (A), respectively. Here we identify foundational mechanistic differences between FTO and ALKBH5 that promote these distinct biochemical outcomes. In contrast to FTO, which follows a traditional oxidative N-demethylation pathway to catalyze conversion of m6A to hm6A with subsequent slow release of A and FA, we find that ALKBH5 catalyzes a direct m6A-to-A transformation with rapid FA release. We identify a catalytic R130/K132/Y139 triad within ALKBH5 that facilitates release of FA via an unprecedented covalent-based demethylation mechanism with direct detection of a covalent intermediate. Importantly, a K132Q mutant furnishes an ALKBH5 enzyme with an m6A demethylation profile that resembles that of FTO, establishing the importance of this residue in the proposed covalent mechanism. Finally, we show that ALKBH5 is an endogenous source of FA in the cell by activity-based sensing of FA fluxes perturbed via ALKBH5 knockdown. This work provides a fundamental biochemical rationale for nonredundant roles of these RNA demethylases beyond different substrate preferences and cellular localization, where m6A demethylation by ALKBH5 versus FTO results in release of FA, an endogenous one-carbon unit but potential genotoxin, at different rates in living systems.
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