Yetrib Hathout

Children's National Medical Center, Washington, Washington, D.C., United States

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Publications (70)258.66 Total impact

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    ABSTRACT: Epigenomic regulation of the transcriptome by DNA methylation and post-transcriptional gene silencing by miRNAs are potential environmental modulators of skeletal muscle plasticity to chronic exercise in healthy and diseased populations. We utilised transcriptome networks to connect exercise-induced differential methylation and miRNA with functional skeletal muscle plasticity. Biopsies of the Vastus lateralis were collected from middle aged Polynesian men and women with morbid obesity (44 kg/m(2) ± 10) and Type-2 diabetes before and following 16 weeks of resistance (n=9) or endurance training (n=8). Longitudinal transcriptome, methylome, and miRNA responses were obtained via microarray, filtered by novel effect-size based false discovery rate probe selection preceding bioinformatic interrogation. Metabolic and microvascular transcriptome topology dominated the network landscape following endurance exercise. Lipid and glucose metabolism modules were connected to: miR-29a; promoter region hypomethylation of nuclear receptor factor (NRF1) and fatty-acid transporter (SLC27A4), and hypermethylation of fatty acid synthase, and to exon hypomethylation of 6-phosphofructo-2-kinase and Ser/Thr protein kinase. Directional change in the endurance networks was validated by lower intramyocellular lipid, increased capillarity, GLUT4, hexokinase and mitochondrial enzyme activity and proteome. Resistance training also lowered lipid, increased enzyme activity, and caused GLUT4-promoter hypomethylation; however, training was inconsequential to GLUT4, capillarity, and metabolic transcriptome. miR-195 connected to negative regulation of vascular development. To conclude, integrated molecular network modelling revealed differential DNA methylation and miRNA expression changes occur in skeletal muscle in response to chronic exercise training that are most pronounced with endurance training and topographically associated with functional metabolic and microvascular plasticity relevant to diabetes rehabilitation.
    Physiological Genomics 08/2014; · 2.81 Impact Factor
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    ABSTRACT: It is expected that serum protein biomarkers in DMD will reflect disease pathogenesis, progression and aid future therapy developments. Here, we describe use of quantitative in vivo stable isotope labeling in mammals to accurately compare serum proteomes of wild type and dystrophin-deficient mdx mice. Biomarkers identified in serum from two independent dystrophin deficient mouse models (mdx-Δ52 and mdx-23), were concordant with those identified in sera samples of DMD patients. Of the 355 mouse sera proteins, 23 were significantly elevated and 4 significantly lower in mdx relative to wild type mice (p value<0.001). Elevated proteins were mostly of muscle origin: including myofibrillar proteins (titin, myosin light chain 1/3, myomesin 3, filamin-C), glycolytic enzymes (aldolase, phosphoglycerate mutase 2, beta enolase, and glycogen phosphorylase), transport proteins (fatty acid binding protein, myoglobin and somatic cytochrome-C), and others (creatine kinase M, malate dehydrogenase cytosolic, fibrinogen and parvalbumin). Decreased proteins, mostly of extracellular origin, included adiponectin, lumican, plasminogen and leukemia inhibitory factor receptor. Analysis of sera from 1 week to 7 months old mdx mice revealed age dependent changes in the level of these biomarkers with most biomarkers acutely elevated at 3 weeks of age. Serum analysis of DMD patients, with ages ranging from 4 to 15 years old, confirmed elevation of 20 of the murine biomarkers in DMD, with similar age-related changes. This study provides a panel of biomarkers that reflect muscle-activity and pathogenesis and should prove valuable tool to complement natural history studies and to monitor treatment efficacy in future clinical trials.
    Human Molecular Genetics 07/2014; · 7.69 Impact Factor
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    ABSTRACT: Objective: The objective of this study is to identify perturbed pathways and assess their contribution to muscle disease in a myositis mouse model. Myositis is characterized by severe weakness. We and others have previously shown that endoplasmic reticulum (ER) stress plays a role in the pathogenesis of myositis. Here we propose that ER stress activates downstream ubiquitin proteasome pathways (UPP) and contributes to muscle degeneration. Methods: An in vivo (13) C6 -Lys-SILAC-mouse was used to identify alterations in the skeletal muscle proteome of myositis mice. Differentially altered protein levels identified in the initial comparisons were validated using a LC-MS/MS spike-in strategy and further confirmed by immunoblotting. In addition, we evaluated the effect of a proteasome inhibitor, bortezomib, on the disease phenotype using well-standardized functional, histological, and biochemical assessments. Results: The SILAC mouse technique identified significant alteration in the levels of proteins belonging to the ER stress response, UPP, oxidative phosphorylation, glycolysis, cytoskeleton, and muscle contractile apparatus categories. We validated the myositis-related changes in the UPP pathway and demonstrated a significant increase in the ubiquitination of muscle proteins as well as a specific increase in ubiquitin carboxyl-terminal hydrolase isozyme L1 (UCHL1) in myositis but not in normal or other dystrophic muscles. Inhibition of UPP with bortezomib significantly improved muscle function and also significantly decreased TNF-α expression in the skeletal muscle of myositis mice. Conclusion: UPP activation in myositis muscle may contribute to muscle degeneration. UCHL-1 is a potential biomarker for disease progression. Inhibition of UPP offers a potential therapeutic strategy for myositis. © 2013 American College of Rheumatology.
    Arthritis & Rheumatology 09/2013; · 7.48 Impact Factor
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    ABSTRACT: The polarity of the conducting airway epithelium is responsible for its directional secretion. This is an essential characteristic of lung integrity and function that dictates interactions between the external environment (apical) and subepithelial structures (basolateral). Defining the directional secretomes in the in vitro human bronchial epithelial (HBE) differentiated model could bring valuable insights into lung biology and pulmonary diseases. Normal primary HBE cells (n=3) were differentiated into respiratory tract epithelium. Apical and basolateral secretions (24h) were processed for proteome profiling and pathway analysis. A total of 243 proteins were identified in secretions from all HBE cultures combined. Of these, 51% were classified as secreted proteins including true secreted proteins (36%) and exosomal proteins (15%). Close examination revealed consistent secretion of 69 apical proteins, 13 basolateral proteins and differential secretion of 25 proteins across all donors. Expression of Annexin A4 in apical secretions and Desmoglein-2 in basolateral secretions was validated using Western blot or ELISA in triplicate independent experiments. To the best of our knowledge, this is the first study defining apical and basolateral secretomes in the in vitro differentitated HBE model. The data demonstrate that epithelial polarity directs protein secretion with different patterns of biological processes to the apical and basolateral surfaces that are consistent with normal bronchial epithelium homeostatic functions. Applying this in vitro directional secretome model to lung diseases may elucidate their molecular pathophysiology and eventually help define potential therapeutic targets.
    American Journal of Respiratory Cell and Molecular Biology 09/2013; · 4.15 Impact Factor
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    ABSTRACT: One of the principal goals of glycoprotein research is to correlate glycan structure and function. Such correlation is necessary to understand the mechanisms whereby glycoprotein structure elaborates the functions of myriad proteins. Accurate comparison of glycoforms and quantification of glycosites is an essential step in this direction. Mass spectrometry has emerged as a powerful analytical technique in the field of glycoprotein characterization. Its sensitivity, high dynamic range, and mass accuracy provide both quantitative and sequence/structural information. As part of the 2012 ABRF Glycoprotein Research Group (gPRG) study, we explored the use of mass spectrometry and ancillary methodologies to characterize the glycoforms of two sources of human prostate specific antigen (PSA). PSA is used as a tumor marker for prostate cancer, with increasing blood levels used to distinguish between normal and cancer states. The glycans on PSA are believed to be biantennary N-linked and it has been observed that prostate cancer tissues and cell lines, contain more antennae than the benign form. Thus, the ability to quantify differences in glycosylation associated with cancer has the potential to positively impact use of PSA as a biomarker. We studied standard peptide based proteomics/glycomics methodologies including LC-MS/MS for peptide/glycopeptide sequencing and label-free approaches for differential quantification. We performed an interlaboratory study to determine the ability of different laboratories to correctly characterize the differences in glycoforms between two different sources using mass spectrometry methods. We used clustering analysis and ancillary statistical data treatment on the data sets submitted by participating laboratories to obtain a consensus of the glycoforms and abundances. The results demonstrate the relative strengths and weaknesses of top-down glycoproteomics, bottom-up glycoproteomics, and glycomics methods, respectively.
    Molecular &amp Cellular Proteomics 06/2013; · 7.25 Impact Factor
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    ABSTRACT: Proteomic analysis of human body fluids is highly challenging, therefore many researchers are redirecting efforts towards secretome profiling. The goal is to define potential biomarkers and therapeutic targets in the secretome that can be traced back in accessible human body fluids. However, currently there is a lack of secretome profiles of normal human primary cells making it difficult to assess the biological meaning of current findings. In this study we sought to establish secretome profiles of human primary cells obtained from healthy donors with the goal of building a human secretome atlas. Such an atlas can be used as a reference for discovery of potential disease associated biomarkers and eventually novel therapeutic targets. As a preliminary study, secretome profiles were established for six different types of human primary cell cultures and checked for overlaps with the three major human body fluids including plasma, cerebrospinal fluid and urine. About 67% of the 1054 identified proteins in the secretome of these primary cells occurred in at least one body fluid. Furthermore, comparison of the secretome profiles of two human glioblastoma cell lines to this new human secretome atlas enabled unambiguous identification of potential brain tumor biomarkers. These biomarkers can be easily monitored in different body fluids using stable isotope labeled standard proteins. The long term goal of this study is to establish a comprehensive online human secretome atlas for future use as a reference for any disease related secretome study.
    Biochimica et Biophysica Acta 04/2013; · 4.66 Impact Factor
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    ABSTRACT: Duchenne muscular dystrophy results from loss of the protein dystrophin, which links the intracellular cytoskeletal network with the extracellular matrix, but deficiency in this function does not fully explain the onset or progression of the disease. While some intracellular events involved in the degeneration of dystrophin-deficient muscle fibers have been well characterized, changes in their secretory profile are undescribed. To analyze the secretome profile of mdx myotubes independently of myonecrosis, we labeled the proteins of mdx and wild-type myotubes with stable isotope-labeled amino acids (SILAC), finding marked enrichment of vesicular markers in the mdx secretome. These included the lysosomal-associated membrane protein, LAMP1, that co-localized in vesicles with an over-secreted cytoskeletal protein, myosin light chain 1. These LAMP1/MLC1-3-positive vesicles accumulated in the cytosol of mdx myotubes and were secreted into the culture medium in a range of abnormal densities. Restitution of dystrophin expression, by exon skipping, to some 30 % of the control value, partially normalized the secretome profile and the excess LAMP1 accumulation. Together, our results suggest that a lack of dystrophin leads to a general dysregulation of vesicle trafficking. We hypothesize that disturbance of the export of proteins through vesicles occurs before, and then concurrently with, the myonecrotic cascade and contributes chronically to the pathophysiology of DMD, thereby presenting us with a range of new potential therapeutic targets.
    Cellular and Molecular Life Sciences CMLS 01/2013; · 5.62 Impact Factor
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    ABSTRACT: Duchenne muscular dystrophy (DMD) is an X-linked neuromuscular disorder caused by a mutation in the dystrophin gene. DMD is characterized by progressive weakness of skeletal, cardiac and respiratory muscles. The molecular mechanisms underlying dystrophy-associated muscle weakness and damage are not well understood. Quantitative proteomic techniques would help to identify disease specific pathways. Recent advances in in vivo metabolic labeling of mammals by stable isotope-labeled amino acids [13C6-lysine (SILAC mouse) or 15N (SILAM)] have enabled accurate quantitative analysis of the proteomes of the whole organs and tissues as a function of disease. Here we describe the use of SILAC mouse strategy to define the underlying pathological mechanisms in dystrophin-deficient skeletal muscle. Differential SILAC proteome profiling was performed on the gastrocnemius muscles of 3-week-old (early stage) dystrophin deficient mdx mice versus wild type (normal) mice. Generated data was further confirmed in an independent set of mdx and normal mice using SILAC spike-in strategy. A total of 789 proteins were quantified, of these 73 were found to be significantly altered between mdx and normal mice. Bioinformatics analyses using Ingenuity Pathway software established that the integrin-linked kinase pathway, actin cytoskeleton signaling, mitochondrial energy metabolism, calcium homeostasis are the initial pathways to be affected in dystrophin deficient muscle at early stage of the pathogenesis. Key proteins involved in these pathways were validated by immunoblotting and immunohistochemistry in independent set of mdx mice samples and in human DMD muscle biopsies. The specific involvement of these molecular networks early in dystrophic pathology makes them potential therapeutic targets. In sum, our findings indicate that SILAC mouse strategy has uncovered previously unidentified pathological pathways in mouse models of human skeletal muscle disease.
    Molecular &amp Cellular Proteomics 01/2013; · 7.25 Impact Factor
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    ABSTRACT: Quantitation of human dystrophin protein in muscle biopsies is a clinically relevant endpoint for both diagnosis and response to dystrophin-replacement therapies for dystrophinopathies. A robust and accurate assay would enable the use of dystrophin as a surrogate biomarker, particularly in exploratory Phase 2 trials. Currently available methods to quantitate dystrophin rely on immunoblot or immunohistochemistry methods that are not considered robust. Here we present a mass spectrometry based approach to accurately quantitate dystrophin protein in a total protein extract from human muscle biopsies. Our approach uses a combination of stable isotope labeled dystrophin as a spike-in standard, gel electrophoresis and high precision mass spectrometry to detect and quantitate multiple peptides of dystrophin within a complex protein mixture. The method was found highly reproducible and linear over a wide dynamic range, detecting as low as 5% of dystrophin relative to the normal amount in healthy individuals.
    Journal of bioanalysis & biomedicine. 12/2012; Suppl 7.
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    ABSTRACT: Skeletal muscles are proficient at healing from a variety of injuries. Healing occurs in two phases, early and late phase. Early phase involves healing the injured sarcolemma and restricting the spread of damage to the injured myofiber. Late phase of healing occurs a few days postinjury and involves interaction of injured myofibers with regenerative and inflammatory cells. Of the two phases, cellular and molecular processes involved in the early phase of healing are poorly understood. We have implemented an improved sarcolemmal proteomics approach together with in vivo labeling of proteins with modified amino acids in mice to study acute changes in the sarcolemmal proteome in early phase of myofiber injury. We find that a notable early phase response to muscle injury is an increased association of mitochondria with the injured sarcolemma. Real-time imaging of live myofibers during injury demonstrated that the increased association of mitochondria with the injured sarcolemma involves translocation of mitochondria to the site of injury, a response that is lacking in cultured myoblasts. Inhibiting mitochondrial function at the time of injury inhibited healing of the injured myofibers. This identifies a novel role of mitochondria in the early phase of healing injured myofibers.
    Journal of Biological Chemistry 07/2012; 287(36):30455-67. · 4.65 Impact Factor
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    ABSTRACT: Studies of the cell secretome have greatly increased in recent years owing to improvements in proteomic platforms, mass spectrometry instrumentation and to the increased interaction between analytical chemists, biologists and clinicians. Several secretome studies have been implemented in different areas of research, leading to the generation of a valuable secretome catalogs. Secreted proteins continue to be an important source of biomarkers and therapeutic target discovery and are equally valuable in the field of microbiology. Several discoveries have been achieved in vitro using cell culture systems, ex vivo using human tissue specimens and in vivo using animal models. In this review, some of the most recent advances in secretome studies and the fields that have benefited the most from this evolving technology are highlighted.
    Expert Review of Proteomics 06/2012; 9(3):337-45. · 3.90 Impact Factor
  • American Thoracic Society 2012 International Conference, May 18-23, 2012 • San Francisco, California; 05/2012
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    ABSTRACT: Transferrin in cerebrospinal fluid (CSF) exists as a mixture of silao and asialo glycoforms believed to originate from liver and brain respectively. We have previously shown that alteration in the asialo glycoform pattern could be an indication of certain anomalies in the central nervous system. Additionally, CSF asialo-transferrin has been shown to be a reliable marker to assess cerebrospinal leakage in head trauma. Therefore, the CSF transferrin glycoform pattern could be a useful diagnostic and prognostic tool. In this study we sought to characterize, in-depth, the transferrin glycovariants in cerebrospinal fluid using a combination of two-dimensional gel electrophoresis and high precision mass spectrometry analysis. Cerebrospinal fluid transferrin was detected as multiple spots (seven major spots) with different isoelectric points and slight shift in apparent molecular mass. High resolution (>60,000) and high accuracy (< 3 ppm error) mass spectrometry analysis revealed that each spot had a unique glycopeptide signature. MS(n) analysis enabled characterization of the glycan structure directly from the in-gel digested spots. The multiple spots detected for cerebrospinal fluid transferrin were mainly due to heterogeneity of di-antennary and tri-antennary glycans harboring a varying number of terminal N-acetylneuraminic acids and the existence of a high mannose and high N-acetylhexosamine glycosylated species.
    International Journal of Mass Spectrometry 02/2012; 312:97-106. · 2.14 Impact Factor
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    ABSTRACT: To bring insights into neurofibroma biochemistry, a comprehensive secretome analysis was performed on cultured human primary Schwann cells isolated from surgically resected plexiform neurofibroma and from normal nerve tissue. Using a combination of SDS-PAGE and high precision LC-MS/MS, 907 proteins were confidently identified in the conditioned media of Schwann cell cultures combined. Label free proteome profiling revealed consistent release of high levels of 22 proteins by the four biological replicates of NF1 Schwann cell cultures relative to the two normal Schwann cell cultures. Inversely, 9 proteins displayed decreased levels in the conditioned media of NF1 relative to normal Schwann cells. The proteins with increased levels included proteins involved in cell growth, angiogenesis and complement pathway while proteins with decreased levels included those involved in cell adhesion, plasminogen pathway and extracellular matrix remodeling. Retinoic acid receptor responder protein-1 (RARRES1), previously described as an integral membrane tumor suppressor, was found exclusively secreted by NF1 Schwann cells but not by normal Schwann cells. All-trans retinoic acid modulated secretion of RARRES1 in a dose dependent manner. This study shows altered secretion of key proteins in NF1 derived Schwann cells. The potential implication of these proteins in neurofibroma biology is discussed.
    International Journal of Molecular Sciences 01/2012; 13(7):9380-99. · 2.46 Impact Factor
  • PROTEOMICS - CLINICAL APPLICATIONS 10/2011; 5(9-10):543. · 1.81 Impact Factor
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    ABSTRACT: Endoplasmic reticulum-mitochondrial contacts, known as mitochondria-associated membranes, regulate important cellular functions including calcium signaling, bioenergetics, and apoptosis. Human cytomegalovirus is a medically important herpesvirus whose growth increases energy demand and depends upon continued cell survival. To gain insight into how human cytomegalovirus infection affects endoplasmic reticulum-mitochondrial contacts, we undertook quantitative proteomics of mitochondria-associated membranes using differential stable isotope labeling by amino acids in cell culture strategy and liquid chromatography-tandem MS analysis. This is the first reported quantitative proteomic analyses of a suborganelle during permissive human cytomegalovirus infection. Human fibroblasts were uninfected or human cytomegalovirus-infected for 72 h. Heavy mitochondria-associated membranes were isolated from paired unlabeled, uninfected cells and stable isotope labeling by amino acids in cell culture-labeled, infected cells and analyzed by liquid chromatography-tandem MS analysis. The results were verified by a reverse labeling experiment. Human cytomegalovirus infection dramatically altered endoplasmic reticulum-mitochondrial contacts by late times. Notable is the increased abundance of several fundamental networks in the mitochondria-associated membrane fraction of human cytomegalovirus-infected fibroblasts. Chaperones, including HSP60 and BiP, which is required for human cytomegalovirus assembly, were prominently increased at endoplasmic reticulum-mitochondrial contacts after infection. Minimal translational and translocation machineries were also associated with endoplasmic reticulum-mitochondrial contacts and increased after human cytomegalovirus infection as were glucose regulated protein 75 and the voltage dependent anion channel, which can form an endoplasmic reticulum-mitochondrial calcium signaling complex. Surprisingly, mitochondrial metabolic enzymes and cytosolic glycolytic enzymes were confidently detected in the mitochondria-associated membrane fraction and increased therein after infection. Finally, proapoptotic regulatory proteins, including Bax, cytochrome c, and Opa1, were augmented in endoplasmic reticulum-mitochondrial contacts after infection, suggesting attenuation of proapoptotic signaling by their increased presence therein. Together, these results suggest that human cytomegalovirus infection restructures the proteome of endoplasmic reticulum-mitochondrial contacts to bolster protein translation at these junctions, calcium signaling to mitochondria, cell survival, and bioenergetics and, thereby, allow for enhanced progeny production.
    Molecular &amp Cellular Proteomics 07/2011; 10(10):M111.009936. · 7.25 Impact Factor
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    ABSTRACT: The incurability of malignant glioblastomas is mainly attributed to their highly invasive nature coupled with resistance to chemo- and radiation therapy. Because invasiveness is partially dictated by the proteins these tumors secrete we used SILAC to characterize the secretomes of four glioblastoma cell lines (LN18, T98, U118 and U87). Although U87 and U118 cells both secreted high levels of well-known invasion promoting proteins, a Matrigel invasion assay showed U87 cells to be eight times more invasive than U118 cells, suggesting that additional proteins secreted by U87 cells may contribute to the highly invasive phenotype. Indeed, we identified a number of proteins highly or exclusively expressed by U87 cells as compared to the less invasive cell lines. The most striking of these include ADAM9, ADAM10, cathepsin B, cathepsin L1, osteopontin, neuropilin-1, semaphorin-7A, suprabasin, and chitinase-3-like protein 1. U87 cells also expressed significantly low levels of some cell adhesion proteins such as periostin and EMILIN-1. Correlation of secretome profiles with relative levels of invasiveness using Pavlidis template matching further indicated potential roles for these proteins in U87 glioblastoma invasion. Antibody inhibition of CH3L1 reduced U87 cell invasiveness by 30%.
    Journal of Proteome Research 05/2011; 10(7):3149-59. · 5.06 Impact Factor
  • American Thoracic Society 2011 International Conference, May 13-18, 2011 • Denver Colorado; 05/2011
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    ABSTRACT: The aims of this study were to demonstrate the feasibility of centrally collecting and processing high-quality cerebrospinal fluid (CSF) samples for proteomic studies within a multi-center consortium and to identify putative biomarkers for medulloblastoma in CSF. We used 2-DE to investigate the CSF proteome from 33 children with medulloblastoma and compared it against the CSF proteome from 25 age-matched controls. Protein spots were subsequently identified by a combination of in-gel tryptic digestion and MALDI-TOF TOF MS analysis. On average, 160 protein spots were detected by 2-DE and 76 protein spots corresponding to 25 unique proteins were identified using MALDI-TOF. Levels of prostaglandin D2 synthase (PGD2S) were found to be six-fold decreased in the tumor samples versus control samples (p<0.00001). These data were further validated using ELISA. Close examination of PGD2S spots revealed the presence of complex sialylated carbohydrates at residues Asn(78) and Asn(87) . Total PGD2S levels are reduced six-fold in the CSF of children with medulloblastoma most likely representing a host response to the presence of the tumor. In addition, our results demonstrate the feasibility of performing proteomic studies on CSF samples collected from patients at multiple institutions within the consortium setting.
    Proteomics 03/2011; 11(5):935-43. · 4.43 Impact Factor
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    ABSTRACT: Uncharacterized open reading frames (ORFs) in human genomic sequence often show a high degree of evolutionary conservation, yet have little or no tissue EST or protein data suggestive of protein product function. The encoded proteins may have highly restricted expression in specialized cells, subcellular specializations, and/or narrow windows during development. One such highly specialized and minute subcellular compartment is the neuromuscular junction (NMJ), where motorneurons contact muscle fibers. The electric Torpedo ray has evolved to expand the NMJ structure to the size of a large organ (electroplax organ), and we hypothesized that Torpedo electroplax proteins would be candidates for human ESTs expressed at the human NMJ. A total of 9719 primary electroplax cDNA clones were sequenced. We identified 44 human ORFs showing high (>63%) amino acid identity to Torpedo electroplax transcripts with enrichment for mRNA splicing motifs (SH2 and pre-mRNA splicing domains), an observation potentially important for the strict nuclear domains maintained by myonuclei underlying the NMJ. We generated antibodies against two uncharacterized human genes (C19orf29 [Drosophila cactin] and C15orf24) and showed that these were indeed expressed at the murine NMJ. Cactin, a member of the Rel transcription factor family in Drosophila, localized to the postsynaptic cytosol of the NMJ and nuclear membrane. C15orf24 protein localized to the murine postsynaptic sarcolemma. We show a novel approach towards identifying proteins expressed at a subcellular specialization using evolutionary diversity of organ function and cross-species mapping.
    Marine Genomics 03/2011; 4(1):33-40. · 1.34 Impact Factor

Publication Stats

970 Citations
258.66 Total Impact Points

Institutions

  • 2005–2014
    • Children's National Medical Center
      • • Center for Genetic Medicine Research
      • • Children's Research Institute (CRI)
      Washington, Washington, D.C., United States
    • The Washington Institute
      Washington, Washington, D.C., United States
  • 2006–2012
    • George Washington University
      • Department of Biomedical Sciences
      Washington, Washington, D.C., United States
  • 1999–2004
    • University of Maryland, College Park
      • Department of Chemistry and Biochemistry
      College Park, MD, United States
  • 1997–1999
    • University of Maryland, Baltimore County
      • Department of Chemistry and Biochemistry
      Baltimore, MD, United States
  • 1996
    • University of Maryland, Baltimore
      Baltimore, Maryland, United States