A Domain Based Protein Structural Modelling Platform Applied in the Analysis of Alternative

Total Page:16

File Type:pdf, Size:1020Kb

A Domain Based Protein Structural Modelling Platform Applied in the Analysis of Alternative A domain based protein structural modelling platform applied in the analysis of alternative splicing Su Datt Lam A thesis submitted for the degree of Doctor of Philosophy January 2018 Institute of Structural and Molecular Biology University College London Declaration I, Su Datt Lam, confirm that the work presented in this thesis is my own except where otherwise stated. Where the thesis is based on work done by myself jointly with others or where information has been derived from other sources, this has been indicated in the thesis. Su Datt Lam January 2018 Abstract Functional families (FunFams) are a sub-classification of CATH protein domain su- perfamilies that cluster relatives likely to have very similar structures and functions. The functional purity of FunFams has been demonstrated by comparing against ex- perimentally determined Enzyme Commission annotations and by checking whether known functional sites coincide with highly conserved residues in the multiple se- quence alignments of FunFams. We hypothesised that clustering relatives into Fun- Fams may help in protein structure modelling. In the first work chapter, we demonstrate the structural coherence of domains in FunFams. We then explore the usage of FunFams in protein monomer modelling. The FunFam based protocol produced higher percentages of good models compared to an HHsearch (the state-of-the-art HMM based sequence search tool) based protocol for both close and remote homologs. We developed a modelling pipeline that, utilises the FunFam protocol, and is able to model up to 70% of domain sequences from human and fly genomes. In the second work chapter, we explore the usage of FunFams in protein complex modelling. Our analysis demonstrated that domain-domain interfaces in FunFams tend to be conserved. The FunFam based complex modelling protocol produced significantly more good quality models when compared to a BLAST based protocol and slightly better than a HHsearch based protocol. In the final work chapter, we employ the FunFam based structural modelling tool to understand the implications of alternative splicing. We focused on isoforms de- rived from mutually exclusively exons (MXEs) for which there is more enriched in pro- teomics data. MXEs which could be mapped to structure show a significant tendency to be exposed to the solvent, are likely to exhibit a significant change in their physio- chemical property and to lie close to a known/predicted functional sites. Our results suggest that MXE events may have a number of important roles in cells generally. Acknowledgements Undertaking this PhD has been a truly life-changing experience for me and it would not have been possible to do without the support and guidance that I received from many people. It has been an amazing experience been able to pursue my studies at the Uni- versity College London. I have gained a lot of scientific knowledge from my research degree and professional development. I would like to thank those that have been instrumental in helping me achieve and reach this stage. First and for most, I would like to express my deepest gratitude to Prof. Christine Orengo, my main supervisor. Thank you for your willingness to accept me to study and work with such a great team of people in your group. All your encouragement, guidance and support has been the powerhouse to keep me motivated throughout these four years. I will definitely miss all those weekly tutorial sessions we had. Thank you for being such a good mentor, Christine. I would like to thank the Malaysia’s Ministry of Education and the National Univer- sity of Malaysia for their financial support. I would like to thank my Thesis committee members, Prof. David Jones, Dr. Konstantinos Thalassinos and Dr. Joanne Santini for their invaluable insight and support during my thesis committee meetings. Special thanks to Dr. Sayoni Das for her constant help and motivation throughout my PhD. Also to Dr. Jonathan Lees for the suggestions and ideas that had driven me to venture into alternative splicing. Appreciation to Dr. Ian Sillitote, Dr. Tony Lewis, Dr. Natalie Dawson and Dr. David Lee for curating the CATH resource and providing computational support when I needed it. Also would like to thank Dr. Paul Ashford for his insight on structural clustering and Dr. Aurelio Moya Garcia for direction and advice on developing my protein complex modelling pipeline and providing the computational scripts to predict allosteric sites. In addition, thanks to all the other members of the Orengo group especially Camilla Pang and Tolulope Adeyelu for always being kind and helpful when I needed it. I also like to thank all my amazing friends when I am off college. I am deeply grateful to Susanna, Jing Wei, Zora for being such an amazing and warm friends. I 5 am also in debt to my fellow housemates/friends, Filsan, Jonas, Alvin, Bruna, Peter, Wagner, Jaimie for all the wonderful times spent and being there for me all the time. My friends back in Malaysia, Yi Ling, Ai Cheng, Beng Si and Lynice, for their best wishes throughout. Last but not the least, heartfelt thanks to my parents, my brothers, my sisters-in- law for their unwavering love and support at the most difficult times. Su Datt September 2017 Contents Contents 6 List of Figures 13 List of Tables 19 List of Abbreviations 20 List of Publications 23 1 Introduction 24 1.1 Experimental techniques to determine the protein structure . 25 1.2 The structures of proteins . 27 1.3 Aligning protein sequences . 30 1.3.1 Multiple sequence alignment . 34 1.4 Database searching . 36 1.4.1 Sequence based . 36 1.4.2 Profile based . 36 1.4.3 Assessing the significance of the result obtained from these pro- grams ............................... 38 1.5 Structure comparison . 39 1.5.1 Structure comparison methods . 39 1.5.2 Performance of structure comparison methods . 43 1.5.3 Structure comparison scores . 44 1.6 Protein structure classification . 46 1.6.1 CATH . 47 1.6.1.1 Gene3D . 48 1.6.1.2 Sub-classification of homologous superfamilies into func- tional families (FunFams) . 49 1.6.2 SCOP . 50 1.7 Overview of Thesis . 51 CONTENTS 7 2 Modelling protein monomers 52 2.1 Introduction . 52 2.1.1 Predicting protein structures . 52 2.1.2 Recent developments in structural modelling . 56 2.1.3 Assessing protein models . 57 2.1.3.1 Protein monomer model quality assessment . 58 2.1.3.2 Recent developments in model quality assessment . 61 2.1.4 Resources dedicated to large-scale comparative modelling of genome sequences . 61 2.1.4.1 ModBase . 62 2.1.4.2 SWISS-MODEL repository . 62 2.1.4.3 Protein Model Portal . 63 2.1.4.4 Genome3D initiative . 64 2.1.5 Objectives . 65 2.2 Materials and Methods . 67 2.2.1 Calculating the structural conservation of structural domains within CATH-Gene3D FunFams and CATH superfamilies . 67 2.2.2 Assessing the model quality assessment methods, query-template alignment and template selection strategy . 67 2.2.2.1 Template selection methods . 68 2.2.2.2 Comparing different model quality assessment methods 69 2.2.2.3 Comparing different query-template alignments methods 69 2.2.2.4 Comparative modelling . 70 2.2.2.5 Assessing the performance of the prediction protocols and ranking the models . 70 2.2.3 Modelling structurally uncharacterised sequences in human and fly.................................. 71 2.3 Results and Discussion . 71 CONTENTS 8 2.3.1 Structural conservation of structural domains within FunFams and across superfamilies . 72 2.3.2 Choosing the best model assessment method . 73 2.3.3 Choosing the best query-template alignment method . 74 2.3.4 Assessing the performance of FunFam and HHsearch template selection methods . 76 2.3.4.1 Close homologues with sequence identity ≥50% . 77 2.3.4.2 Close homologues with sequence identity 30%-50% . 78 2.3.4.3 Remote homologues with sequence identity <30% se- quence identity . 78 2.3.4.4 Which protocol selects a higher proportion of good templates than the other protocol . 80 2.3.5 Modelling human and fly genomes . 81 2.3.5.1 Analysis of model quality for human and fly genes us- ing FunFams and HHsearch (CATH) . 82 2.3.5.2 Analysis involved FunFams and all the HHsearch li- braries . 84 2.4 Conclusions . 87 2.4.1 Future directions . 88 2.4.2 Uses of structural modelling in experimental studies . 89 2.4.2.1 Facilitation of cryo-EM density map fitting with homol- ogy models . 89 2.4.2.2 Integrative structural biology . 90 3 Modelling protein-protein interactions 91 3.1 Introduction . 91 3.1.1 Structural modelling of protein complexes . 99 3.1.1.1 Template-free modelling/docking . 99 3.1.1.2 Template based modelling . 101 CONTENTS 9 3.1.2 Community-wide protein complex modelling assessment exper- iment . 105 3.1.2.1 Assessing the performance of modelling methods . 106 3.2 Objectives . 107 3.3 Materials and Methods . 107 3.3.1 Investigating the conservation of protein-protein interfaces in CATH-Gene3D FunFams . 107 3.3.1.1 Generating a library of CATH-Gene3D FunFam domain- domain interfaces . 107 3.3.1.2 Calculating the conservation of protein-protein inter- faces within FunFams and between FunFams across a superfamily . 108 3.3.2 Modelling protein complexes - Template based modelling (MOD- ELLER) . 111 3.3.2.1 Complex modelling pipelines . 111 3.3.2.2 Comparing different ways of selecting the best templates112 3.3.2.3 Benchmark dataset used in the comparison of the Fun- Fam protocol with the Interactome3D protocol (Chain- chain interactions) . 113 3.3.2.4 Benchmark dataset used in the HHsearch comparison (DDIs) .
Recommended publications
  • Atnea1-Identification and Characterization of a Novel Plant Nuclear Envelope Associated Protein
    Vol. 13(7), pp. 844-856, 12 February, 2014 DOI: 10.5897/AJB2013.13078 ISSN 1684-5315 ©2014 Academic Journals African Journal of Biotechnology http://www.academicjournals.org/AJB Full Length Research Paper AtNEA1-identification and characterization of a novel plant nuclear envelope associated protein Ting Lu Department of Biological and Medical Sciences, Oxford Brookes University, Oxford OX3 0BP, UK. Accepted 29 January, 2014 In animal and yeast cells, a cross nuclear envelope structure linker of nucleoskeleton and cytoskeleton (LINC) is formed by outer nuclear membrane SUN proteins and inner nuclear membrane KASH proteins. However, little information was acquired about plant SUN-KASH structure until they were found in plant SUN proteins in 2010 and KASH proteins in 2012. The SUN-KASH complex alongside with actin in the microfilament cytoskeleton and nucleaoskeleton together shape the main cell skeleton structure and involve in many important biological functions including cell structure stability, cell movement and cell division. In searching of other plant nuclear envelope associated proteins, arabidopsis nuclear envelop associated (AtNEA1) protein 1, a plant nucleoplasmic protein, was identified from biological studies. AtNEA1 was predicted to have a nuclear localisation signal (NLS), two coiled coil domains and one transmembrane (TM) domain. The mutants with the deletion of respective putative domains were observed under confocal microscopy. The subcellular localisation of mutants implied that putative NLS is not essential for AtNEA1 to diffuse through NPC but can strongly increase the efficiency, both coiled coil domains participate in the interaction of AtNEA1 with its unknown INM intrinsic interaction partner, and putative TM appeared to be non-functional.
    [Show full text]
  • Identification of Plant SUN Domain-Interacting Tail Proteins and Analysis of Their Function in Nuclear Positioning
    Identification of Plant SUN Domain-Interacting Tail Proteins and Analysis of Their Function in Nuclear Positioning DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of the Ohio State University By Xiao Zhou, M. S. Graduate Program in Plant Cellular and Molecular Biology The Ohio State University 2013 Dissertation Committee: Professor Iris Meier, Advisor Professor Biao Ding Professor Stephen Osmani Professor R. Keith Slotkin Copyright by Xiao Zhou 2013 Abstract The nuclear envelope (NE) is a double membrane system consisting of an inner nuclear membrane (INM) and an outer nuclear membrane (ONM). Studies in opisthokonts revealed that the two membranes are bridged by protein complexes formed by the INM Sad1/UNC-84 (SUN) proteins and the ONM Klarsicht/ANC-1/Syne-1 homology (KASH) proteins. These SUN-KASH NE bridges are usually linkers of the nucleoskeleton to the cytoskeleton (LINC) conserved across eukaryotes. LINC complexes are key players in multiple cellular processes, such as nuclear and chromosomal positioning and nuclear shape determination, which in turn influence the gametogenesis and several aspects of development. Although these cellular processes have long been also known in plants, no KASH proteins are encoded in the plant genomes. I identified WPP domain interacting proteins (WIPs) as the first plant KASH protein analogs. WIPs are plant-specific ONM proteins that redundantly anchor Ran GTPase activating protein (RanGAP) to the NE. Arabidopsis thaliana WIPs (AtWIPs) interact with Arabidopsis thaliana SUN proteins (AtSUNs), which is required for both AtWIP1 and AtRanGAP1 NE localization. In addition, AtWIPs and AtSUNs are necessary for maintaining the elongated nuclear shape of Arabidopsis epidermal cells.
    [Show full text]
  • Nesprins: from the Nuclear Envelope and Beyond
    expert reviews http://www.expertreviews.org/ in molecular medicine Nesprins: from the nuclear envelope and beyond Dipen Rajgor and Catherine M. Shanahan* Nuclear envelope spectrin-repeat proteins (Nesprins), are a novel family of nuclear and cytoskeletal proteins with rapidly expanding roles as intracellular scaffolds and linkers. Originally described as proteins that localise to the nuclear envelope (NE) and establish nuclear-cytoskeletal connections, nesprins have now been found to comprise a diverse spectrum of tissue specific isoforms that localise to multiple sub-cellular compartments. Here, we describe how nesprins are necessary in maintaining cellular architecture by acting as essential scaffolds and linkers at both the NE and other sub-cellular domains. More importantly, we speculate how nesprin mutations may disrupt tissue specific nesprin scaffolds and explain the tissue specific nature of many nesprin-associated diseases, including laminopathies. The eukaryotic cytoplasm contains three major composed of three α-helical bundles with a left- types of cytoskeletal filaments: Filamentous- handed twist, and its primary function is to actin (F-actin), microtubules (MTs) and provide docking sites for proteins and other intermediate filaments (IFs). These components higher order complexes (Refs 3, 4). Although are organised in a manner that provides the cell most SR proteins contain CHDs, some possess with an internal framework fundamental for motifs which can interact with other cytoskeletal many processes, such as controlling cellular components, allowing linkage of SR-associated shape, polarity, adhesion and migration, complexes to filamentous structures other than cytokinesis, inter- and intracellular F-actin. In addition, these motifs allow cross- Nesprins: from the nuclear envelope and beyond communication and trafficking of organelles, linking between different filaments and dynamic vesicles, proteins and RNA (Refs 1, 2).
    [Show full text]
  • New Methods for the Prediction and Classification of Protein Domains
    New Methods for the Prediction and Classi¯cation of Protein Domains Jan Erik Gewehr MÄunchen2007 New Methods for the Prediction and Classi¯cation of Protein Domains Jan Erik Gewehr Dissertation an der FakultÄatfÄurMathematik und Informatik der Ludwig{Maximilians{UniversitÄat MÄunchen vorgelegt von Jan Erik Gewehr aus LÄubeck MÄunchen, den 01.10.2007 Erstgutachter: Prof. Dr. Ralf Zimmer Zweitgutachter: Prof. Dr. Dmitrij Frishman Tag der mÄundlichen PrÄufung:19.12.2007 Contents 1 Motivation and Overview 1 1.1 The Bene¯t of Protein Structure Prediction ................. 1 1.2 Thesis Outline .................................. 3 2 Introduction to Protein Structure Prediction 7 2.1 Protein Structures and Related Databases .................. 7 2.1.1 From Primary to Tertiary Structure .................. 7 2.1.2 Structure-Related Databases ...................... 8 2.2 Assignment of Protein Domains ........................ 10 2.2.1 An Old Problem ............................ 10 2.2.2 Comparison of Domain Assignments . 11 2.3 Structure Prediction Categories ........................ 13 2.3.1 Comparative Modeling ......................... 13 2.3.2 Fold Recognition ............................ 14 2.3.3 Ab Initio ................................. 15 2.4 Community-Wide E®orts ............................ 15 2.4.1 Community-Wide Experiments .................... 15 2.4.2 Structural Genomics and Structure Prediction . 16 2.5 Alignment Methods ............................... 16 2.5.1 Sequence Alignment .......................... 16 2.5.2 Alignment Methods used in this Work . 19 3 Selection of Fold Classes based on Secondary Structure Elements 23 3.1 Introduction ................................... 23 3.2 Material ..................................... 25 3.2.1 Training and Test Data ......................... 25 3.2.2 Quoted Methods ............................ 27 3.3 Preselection of Fold Classes .......................... 28 3.3.1 Secondary Structure Element Alignment (SSEA) . 28 3.3.2 Selection Strategies based on SSEA .
    [Show full text]
  • The Nuclear Envelope: Target and Mediator of the Apoptotic Process Liora Lindenboim1, Hila Zohar1,Howardj.Worman2 and Reuven Stein1
    Lindenboim et al. Cell Death Discovery (2020) 6:29 https://doi.org/10.1038/s41420-020-0256-5 Cell Death Discovery REVIEW ARTICLE Open Access The nuclear envelope: target and mediator of the apoptotic process Liora Lindenboim1, Hila Zohar1,HowardJ.Worman2 and Reuven Stein1 Abstract Apoptosis is characterized by the destruction of essential cell organelles, including the cell nucleus. The nuclear envelope (NE) separates the nuclear interior from the cytosol. During apoptosis, the apoptotic machinery, in particular caspases, increases NE permeability by cleaving its proteins, such as those of the nuclear pore complex (NPC) and the nuclear lamina. This in turns leads to passive diffusion of cytosolic apoptogenic proteins, such as caspases and nucleases, through NPCs into the nucleus and the subsequent breakdown of the NE and destruction of the nucleus. However, NE leakiness at early stages of the apoptotic process can also occur in a caspase-independent manner, where Bax, by a non-canonical action, promotes transient and repetitive localized generation and subsequent rupture of nuclear protein-filled nuclear bubbles. This NE rupture leads to discharge of apoptogenic nuclear proteins from the nucleus to the cytosol, a process that can contribute to the death process. Therefore, the NE may play a role as mediator of cell death at early stages of apoptosis. The NE can also serve as a platform for assembly of complexes that regulate the death process. Thus, the NE should be viewed as both a mediator of the cell death process and a target. 1234567890():,; 1234567890():,; 1234567890():,; 1234567890():,; Facts redistribution of the nuclear proteins to the cytosol that might subsequently act as amplifiers of the ● The NE is an important target of the apoptotic apoptotic process.
    [Show full text]
  • Table S4. Trophoblast Differentiation-Associated Genes
    Table S4. Trophoblast differentiation-associated genes Gene Stem Chromosomal Affymetrix ID Gene Title Symbol Ave Dif Ave GenBank Location dif/ stem t-test 1390511_at LOC308394 Cgm4 10 1863 BI285801 1 193.51 0.006 1378534_at similar to brain carcinoembryonic antigen LOC308394 10 1746 NM_001025679 1q21 183.10 0.001 1388433_at keratin complex 1, acidic, gene 19 Krt1-19 53 7958 NM_199498 10q32.1 149.07 0.022 1369029_at phospholipid scramblase 1 Plscr1 20 2050 NM_057194 8q31 101.12 0.028 1389856_at carcinoembryonic antigen gene family 4 Cgm4 57 5073 NM_012525 1q21 89.73 0.001 carcinoembryonic antigen-related cell 1368996_at adhesion molecule 3 Ceacam3 202 17879 NM_012702 1q21 88.71 0.001 1392832_at similar to angiopoietin-like 1 LOC684489 17 1398 XM_001068284 --- 83.66 0.001 1377666_at choline dehydrogenase Chdh 26 1571 NM_198731 16p16 60.59 0.003 cytochrome P450, family 11, subfamily a, 1368468_at polypeptide 1 Cyp11a1 196 9216 NM_017286 8q24 47.11 0.000 1376934_x_at similar to brain carcinoembryonic antigen Cgm4 53 2146 BI285801 1 40.22 0.000 stimulated by retinoic acid gene 6 homolog 1390525_a_at (mouse) Stra6 28 1037 NM_001029924 8q24 37.44 0.001 1382690_at carcinoembryonic antigen gene family 4 Cgm4 81 2729 NM_012525 1q21 33.86 0.001 1367809_at prolactin family 4, subfamily a, member 1 Prl4a1 683 22573 NM_017036 17p11 33.05 0.004 calcium channel, voltage-dependent, L type, 1383458_at alpha 1D subunit Cacna1d 26 802 BF403759 16 30.89 0.001 1370852_at spleen protein 1 precursor LOC171573 692 20968 NM_138537 8q21 30.29 0.003 1376036_at transporter
    [Show full text]
  • A Stochastic Point Cloud Sampling Method for Multi-Template Protein Comparative Modeling
    www.nature.com/scientificreports OPEN A Stochastic Point Cloud Sampling Method for Multi-Template Protein Comparative Modeling Received: 05 November 2015 Jilong Li1 & Jianlin Cheng1,2 Accepted: 21 April 2016 Generating tertiary structural models for a target protein from the known structure of its homologous Published: 10 May 2016 template proteins and their pairwise sequence alignment is a key step in protein comparative modeling. Here, we developed a new stochastic point cloud sampling method, called MTMG, for multi-template protein model generation. The method first superposes the backbones of template structures, and the Cα atoms of the superposed templates form a point cloud for each position of a target protein, which are represented by a three-dimensional multivariate normal distribution. MTMG stochastically resamples the positions for Cα atoms of the residues whose positions are uncertain from the distribution, and accepts or rejects new position according to a simulated annealing protocol, which effectively removes atomic clashes commonly encountered in multi-template comparative modeling. We benchmarked MTMG on 1,033 sequence alignments generated for CASP9, CASP10 and CASP11 targets, respectively. Using multiple templates with MTMG improves the GDT-TS score and TM-score of structural models by 2.96–6.37% and 2.42–5.19% on the three datasets over using single templates. MTMG’s performance was comparable to Modeller in terms of GDT-TS score, TM-score, and GDT-HA score, while the average RMSD was improved by a new sampling approach. The MTMG software is freely available at: http://sysbio.rnet.missouri.edu/multicom_toolbox/mtmg.html. The tertiary structure of a protein, which can be represented by the coordinates of its atoms, is important for understanding the function and activity of the protein1,2.
    [Show full text]
  • Human Induced Pluripotent Stem Cell–Derived Podocytes Mature Into Vascularized Glomeruli Upon Experimental Transplantation
    BASIC RESEARCH www.jasn.org Human Induced Pluripotent Stem Cell–Derived Podocytes Mature into Vascularized Glomeruli upon Experimental Transplantation † Sazia Sharmin,* Atsuhiro Taguchi,* Yusuke Kaku,* Yasuhiro Yoshimura,* Tomoko Ohmori,* ‡ † ‡ Tetsushi Sakuma, Masashi Mukoyama, Takashi Yamamoto, Hidetake Kurihara,§ and | Ryuichi Nishinakamura* *Department of Kidney Development, Institute of Molecular Embryology and Genetics, and †Department of Nephrology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan; ‡Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Hiroshima, Japan; §Division of Anatomy, Juntendo University School of Medicine, Tokyo, Japan; and |Japan Science and Technology Agency, CREST, Kumamoto, Japan ABSTRACT Glomerular podocytes express proteins, such as nephrin, that constitute the slit diaphragm, thereby contributing to the filtration process in the kidney. Glomerular development has been analyzed mainly in mice, whereas analysis of human kidney development has been minimal because of limited access to embryonic kidneys. We previously reported the induction of three-dimensional primordial glomeruli from human induced pluripotent stem (iPS) cells. Here, using transcription activator–like effector nuclease-mediated homologous recombination, we generated human iPS cell lines that express green fluorescent protein (GFP) in the NPHS1 locus, which encodes nephrin, and we show that GFP expression facilitated accurate visualization of nephrin-positive podocyte formation in
    [Show full text]
  • The Emerin-Binding Transcription Factor Lmo7 Is Regulated by Association with P130cas at Focal Adhesions
    The emerin-binding transcription factor Lmo7 is regulated by association with p130Cas at focal adhesions Michele A. Wozniak1,2 , Brendon M. Baker2, Christopher S. Chen2 and Katherine L. Wilson1 1 Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA 2 Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA ABSTRACT Loss of function mutations in the nuclear inner membrane protein, emerin, cause X-linked Emery-Dreifuss muscular dystrophy (X-EDMD). X-EDMD is character- ized by contractures of major tendons, skeletal muscle weakening and wasting, and cardiac conduction system defects. The transcription factor Lmo7 regulates muscle- and heart-relevant genes and is inhibited by binding to emerin, suggesting Lmo7 misregulation contributes to EDMD disease. Lmo7 associates with cell adhesions and shuttles between the plasma membrane and nucleus, but the regulation and biological consequences of this dual localization were unknown. We report endoge- nous Lmo7 also associates with focal adhesions in cells, and both co-localizes and co-immunoprecipitates with p130Cas, a key signaling component of focal adhesions. Lmo7 nuclear localization and transcriptional activity increased significantly in p130Cas-null MEFs, suggesting Lmo7 is negatively regulated by p130Cas-dependent association with focal adhesions. These results support EDMD models in which Lmo7 is a downstream mediator of integrin-dependent signaling that allows tendon cells and muscles to adapt to and withstand mechanical stress. Subjects Submitted 14 April 2013 Biochemistry, Cell Biology, Molecular Biology Accepted 29 July 2013 Keywords Lmo7, p130Cas, Focal adhesions, Emery-Dreifuss muscular dystrophy, Laminopathy, Published 20 August 2013 LEM-domain, Nuclear envelope, Nucleoskeleton, Tendon, Emerin Corresponding author Katherine L.
    [Show full text]
  • Sharmin Supple Legend 150706
    Supplemental data Supplementary Figure 1 Generation of NPHS1-GFP iPS cells (A) TALEN activity tested in HEK 293 cells. The targeted region was PCR-amplified and cloned. Deletions in the NPHS1 locus were detected in four clones out of 10 that were sequenced. (B) PCR screening of human iPS cell homologous recombinants (C) Southern blot screening of human iPS cell homologous recombinants Supplementary Figure 2 Human glomeruli generated from NPHS1-GFP iPS cells (A) Morphological changes of GFP-positive glomeruli during differentiation in vitro. A different aggregate from the one shown in Figure 2 is presented. Lower panels: higher magnification of the areas marked by rectangles in the upper panels. Note the shape changes of the glomerulus (arrowheads). Scale bars: 500 µm. (B) Some, but not all, of the Bowman’s capsule cells were positive for nephrin (48E11 antibody: magenta) and GFP (green). Scale bars: 10 µm. Supplementary Figure 3 Histology of human podocytes generated in vitro (A) Transmission electron microscopy of the foot processes. Lower magnification of Figure 4H. Scale bars: 500 nm. (B) (C) The slit diaphragm between the foot processes. Higher magnification of the 1 regions marked by rectangles in panel A. Scale bar: 100 nm. (D) Absence of mesangial or vascular endothelial cells in the induced glomeruli. Anti-PDGFRβ and CD31 antibodies were used to detect the two lineages, respectively, and no positive signals were observed in the glomeruli. Podocytes are positive for WT1. Nuclei are counterstained with Nuclear Fast Red. Scale bars: 20 µm. Supplementary Figure 4 Cluster analysis of gene expression in various human tissues (A) Unbiased cluster analysis across various human tissues using the top 300 genes enriched in GFP-positive podocytes.
    [Show full text]
  • Connecting the Nucleus to the Cytoskeleton by SUN–KASH
    COCEBI-1074; NO. OF PAGES 6 Available online at www.sciencedirect.com Connecting the nucleus to the cytoskeleton by SUN–KASH bridges across the nuclear envelope Erin C Tapley and Daniel A Starr The nuclear–cytoskeleton connection influences many aspects with a wide variety of cytoskeletal components [11]. of cellular architecture, including nuclear positioning, the Mutations in mammalian SUN and KASH proteins lead stiffness of the global cytoskeleton, and mechanotransduction. to developmental defects in neurogenesis, gametogen- Central to all of these processes is the assembly and function of esis, myogenesis, cilliogenesis, and retina formation and conserved SUN–KASH bridges, or LINC complexes, that span contribute to human diseases, including muscular dystro- the nuclear envelope. Recent studies provide details of the phy, ataxia, Progeria, lissencephaly, and cancer higher order assembly and targeting of SUN proteins to the [11,17,18,19,20 ]. inner nuclear membrane. Structural studies characterize SUN– KASH interactions that form the central link of the nuclear- The rapidly growing field of nuclear–cytoskeletal inter- envelope bridge. KASH proteins at the outer nuclear membrane actions has recently been reviewed [11–13]. Here, with link the nuclear envelope to the cytoskeleton where forces are apologies to the rest of the field, we focus on five major generated to move nuclei. Significantly, SUN proteins were findings reported over the past two years. The first step of recently shown to contribute to the progression of building the SUN–KASH bridge is recruiting SUN laminopathies. proteins to the inner nuclear membrane. Surprisingly, trafficking SUN proteins to the inner nuclear membrane Address involves multiple, partially redundant mechanisms Department of Molecular and Cellular Biology, University of California, [21 ,22 ,23 ].
    [Show full text]
  • Emodel-BDB: a Database of Comparative Structure Models Of
    GigaScience, 7, 2018, 1–9 doi: 10.1093/gigascience/giy091 Advance Access Publication Date: 24 July 2018 Research RESEARCH eModel-BDB: a database of comparative structure models of drug-target interactions from the Binding Database Misagh Naderi 1, Rajiv Gandhi Govindaraj 1 and Michal Brylinski 1,2,* 1Department of Biological Sciences, Louisiana State University, 202 Life Sciences Bldg, Baton Rouge, LA 70803, USA and 2Center for Computation & Technology, Louisiana State University, 2054 Digital Media Center, Baton Rouge, LA 70803, USA ∗Correspondence address. Michal Brylinski, Louisiana State University, 202 Life Sciences Bldg, Baton Rouge, LA 70803, USA; Tel: +(225) 578-2791; Fax: +(225) 578-2597; E-mail: [email protected] http://orcid.org/0000-0002-6204-2869 Abstract Background: The structural information on proteins in their ligand-bound conformational state is invaluable for protein function studies and rational drug design. Compared to the number of available sequences, not only is the repertoire of the experimentally determined structures of holo-proteins limited, these structures do not always include pharmacologically relevant compounds at their binding sites. In addition, binding affinity databases provide vast quantities of information on interactions between drug-like molecules and their targets, however, often lacking structural data. On that account, there is a need for computational methods to complement existing repositories by constructing the atomic-level models of drug-protein assemblies that will not be determined experimentally in the near future. Results: We created eModel-BDB, a database of 200,005 comparative models of drug-bound proteins based on 1,391,403 interaction data obtained from the Binding Database and the PDB library of 31 January 2017.
    [Show full text]