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Rusconi D, Negri G, Colapietro P, Picinelli C, Milani D, Spena S, Magnani C, Silengo MC, Sorasio L, Curtisova V, Cavaliere ML, Prontera P, Stangoni G, Ferrero GB, Biamino E, Fischetto R, Piccione M, Gasparini P, Salviati L, Selicorni A, Finelli P, Larizza L, Gervasini C. Characterization of 14 novel deletions underlying Rubinstein-Taybi syndrome: an update of the CREBBP deletion repertoire. Hum Genet 2015; 134:613-26. [PMID: 25805166 DOI: 10.1007/s00439-015-1542-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 03/11/2015] [Indexed: 11/25/2022]
Abstract
Rubinstein-Taybi syndrome (RSTS) is a rare, clinically heterogeneous disorder characterized by cognitive impairment and several multiple congenital anomalies. The syndrome is caused by almost private point mutations in the CREBBP (~55% of cases) and EP300 (~8%) genes. The CREBBP mutational spectrum is variegated and characterized by point mutations (30-50 %) and deletions (~10%). The latter are diverse in size and genomic position and remove either the whole CREBBP gene and its flanking regions or only an intragenic portion. Here, we report 14 novel CREBBP deletions ranging from single exons to the whole gene and flanking regions which were identified by applying complementary cytomolecular techniques: fluorescence in situ hybridization, multiplex ligation-dependent probe amplification and array comparative genome hybridization, to a large cohort of RSTS patients. Deletions involving CREBBP account for 23% of our detected CREBBP mutations, making an important contribution to the mutational spectrum. Genotype-phenotype correlations revealed that patients with CREBBP deletions extending beyond this gene did not always have a more severe phenotype than patients harboring CREBBP point mutations, suggesting that neighboring genes play only a limited role in the etiopathogenesis of CREBBP-centerd contiguous gene syndrome. Accordingly, the extent of the deletion is not predictive of the severity of the clinical phenotype.
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Affiliation(s)
- Daniela Rusconi
- Medical Genetics, Department of Health Sciences, Università degli Studi di Milano, Via A. di Rudinì, 8, 20142, Milan, Italy
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2
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Rhodes DA, Chen HC, Price AJ, Keeble AH, Davey MS, James LC, Eberl M, Trowsdale J. Activation of human γδ T cells by cytosolic interactions of BTN3A1 with soluble phosphoantigens and the cytoskeletal adaptor periplakin. THE JOURNAL OF IMMUNOLOGY 2015; 194:2390-8. [PMID: 25637025 PMCID: PMC4337483 DOI: 10.4049/jimmunol.1401064] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The three butyrophilin BTN3A molecules, BTN3A1, BTN3A2, and BTN3A3, are members of the B7/butyrophilin-like group of Ig superfamily receptors, which modulate the function of T cells. BTN3A1 controls activation of human Vγ9/Vδ2 T cells by direct or indirect presentation of self and nonself phosphoantigens (pAg). We show that the microbial metabolite (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate binds to the intracellular B30.2 domain of BTN3A1 with an affinity of 1.1 μM, whereas the endogenous pAg isopentenyl pyrophosphate binds with an affinity of 627 μM. Coculture experiments using knockdown cell lines showed that in addition to BTN3A1, BTN3A2 and BTN3A3 transmit activation signals to human γδ T cells in response to (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate and the aminobisphosphonate drug zoledronate that causes intracellular accumulation of isopentenyl pyrophosphate. The plakin family member periplakin, identified in yeast two-hybrid assays, interacted with a membrane-proximal di-leucine motif, located proximal to the B30.2 domain in the BTN3A1 cytoplasmic tail. Periplakin did not interact with BTN3A2 or BTN3A3, which do not contain the di-leucine motif. Re-expression into a BTN3A1 knockdown line of wild-type BTN3A1, but not of a variant lacking the periplakin binding motif, BTN3A1Δexon5, restored γδ T cell responses, demonstrating a functional role for periplakin interaction. These data, together with the widespread expression in epithelial cells, tumor tissues, and macrophages detected using BTN3A antiserum, are consistent with complex functions for BTN3A molecules in tissue immune surveillance and infection, linking the cell cytoskeleton to γδ T cell activation by indirectly presenting pAg to the Vγ9/Vδ2 TCR.
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Affiliation(s)
- David A Rhodes
- Immunology Division, Department of Pathology, University of Cambridge, Cambridge Institute for Medical Research, Cambridge CB2 0XY, United Kingdom;
| | - Hung-Chang Chen
- Cardiff Institute of Infection & Immunity, School of Medicine, Cardiff University, Heath Park, Cardiff CF14 4XN, United Kingdom; and
| | - Amanda J Price
- Protein and Nucleic Acid Chemistry Division, Medical Research Council Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom
| | - Anthony H Keeble
- Protein and Nucleic Acid Chemistry Division, Medical Research Council Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom
| | - Martin S Davey
- Cardiff Institute of Infection & Immunity, School of Medicine, Cardiff University, Heath Park, Cardiff CF14 4XN, United Kingdom; and
| | - Leo C James
- Protein and Nucleic Acid Chemistry Division, Medical Research Council Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom
| | - Matthias Eberl
- Cardiff Institute of Infection & Immunity, School of Medicine, Cardiff University, Heath Park, Cardiff CF14 4XN, United Kingdom; and
| | - John Trowsdale
- Immunology Division, Department of Pathology, University of Cambridge, Cambridge Institute for Medical Research, Cambridge CB2 0XY, United Kingdom
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Johnson JL, Najor NA, Green KJ. Desmosomes: regulators of cellular signaling and adhesion in epidermal health and disease. Cold Spring Harb Perspect Med 2014; 4:a015297. [PMID: 25368015 DOI: 10.1101/cshperspect.a015297] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Desmosomes are intercellular junctions that mediate cell-cell adhesion and anchor the intermediate filament network to the plasma membrane, providing mechanical resilience to tissues such as the epidermis and heart. In addition to their critical roles in adhesion, desmosomal proteins are emerging as mediators of cell signaling important for proper cell and tissue functions. In this review we highlight what is known about desmosomal proteins regulating adhesion and signaling in healthy skin-in morphogenesis, differentiation and homeostasis, wound healing, and protection against environmental damage. We also discuss how human diseases that target desmosome molecules directly or interfere indirectly with these mechanical and signaling functions to contribute to pathogenesis.
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Affiliation(s)
- Jodi L Johnson
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611 Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Nicole A Najor
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Kathleen J Green
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611 Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
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4
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MATSUMOTO K, IKEDA M, SATO Y, KURUMA H, KAMATA Y, NISHIMORI T, TOMONAGA T, NOMURA F, EGAWA S, IWAMURA M. Loss of periplakin expression is associated with pathological stage and cancerspecific survival in patients with urothelial carcinoma of the urinary bladder. Biomed Res 2014; 35:201-6. [DOI: 10.2220/biomedres.35.201] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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5
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Ito S, Satoh J, Matsubara T, Shah YM, Ahn SH, Anderson CR, Shan W, Peters JM, Gonzalez FJ. Cholestasis induces reversible accumulation of periplakin in mouse liver. BMC Gastroenterol 2013; 13:116. [PMID: 23849208 PMCID: PMC3716950 DOI: 10.1186/1471-230x-13-116] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 07/12/2013] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Periplakin (PPL) is a rod-shaped cytolinker protein thought to connect cellular adhesion junctional complexes to cytoskeletal filaments. PPL serves as a structural component of the cornified envelope in the skin and interacts with various types of proteins in cultured cells; its level decreases dramatically during tumorigenic progression in human epithelial tissues. Despite these intriguing observations, the physiological roles of PPL, especially in non-cutaneous tissues, are still largely unknown. Because we observed a marked fluctuation of PPL expression in mouse liver in association with the bile acid receptor farnesoid X receptor (FXR) and cholestasis, we sought to characterize the role of PPL in the liver and determine its contributions to the etiology and pathogenesis of cholestasis. METHODS Time- and context-dependent expression of PPL in various mouse models of hepatic and renal disorders were examined by immunohistochemistry, western blotting, and quantitative real-time polymerase chain reactions. RESULTS The hepatic expression of PPL was significantly decreased in Fxr-/- mice. In contrast, the expression was dramatically increased during cholestasis, with massive PPL accumulation observed at the boundaries of hepatocytes in wild-type mice. Interestingly, the hepatic accumulation of PPL resulting from cholestasis was reversible. In addition, similar accumulation of PPL at cellular boundaries was found in epithelial cells around renal tubules upon ureteral obstruction. CONCLUSIONS PPL may be involved in the temporal accommodation to fluid stasis in different tissues. Further examination of the roles for PPL may lead to the discovery of a novel mechanism for cellular protection by cytolinkers that is applicable to many tissues and in many contexts.
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Affiliation(s)
- Shinji Ito
- Biofrontier Platform, Graduate School of Medicine, Kyoto University, Yoshida Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan.
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6
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Suzuki A, Horiuchi A, Ashida T, Miyamoto T, Kashima H, Nikaido T, Konishi I, Shiozawa T. Cyclin A2 confers cisplatin resistance to endometrial carcinoma cells via up-regulation of an Akt-binding protein, periplakin. J Cell Mol Med 2011; 14:2305-17. [PMID: 19583808 PMCID: PMC3822571 DOI: 10.1111/j.1582-4934.2009.00839.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Although overexpression of cyclin A2 is reportedly an indicator of a poor prognosis of various malignancies including endometrial carcinoma, its molecular mechanism remains undetermined. To address this issue, we examined the effect of cyclin A2 on the development of resistance to chemotherapeutic drugs. The expression of cyclin A2 protein was increased in advanced-stage and chemotherapy-refractory stage endometrial carcinomas compared with that in early-stage tumours. The expression levels of cyclin A2 in endometrial carcinoma cell lines correlated positively with the IC50 for cisplatin. Endometrial carcinoma HHUA cells that overexpressed cyclin A2 showed increased resistance to cisplatin in vitro and in vivo, via the activation of a survival pathway, the inositol-3 phosphate kinase (PI3K) cascade. The use of a cDNA microarray identified an Akt-binding protein, periplakin, as a novel target of cyclin A2. The cyclin A2-induced up-regulation of periplakin was mediated via direct binding of Sp1 to the promoter that was activated by cyclin A2 along with chromatin remodelling involving CBP/p300, and the siRNA-mediated silencing of periplakin suppressed the PI3K pathway. These results indicate cyclin A2 to be involved in the acquisition of aggressive behaviour of tumour cells through the activation of PI3K by cyclin A2-induced periplakin, and to be a promising therapeutic target.
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Affiliation(s)
- Akihisa Suzuki
- Department of Obstetrics and Gynecology, Shinshu University School of Medicine, Matsumoto, Japan
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Aho S, Li K, Ryoo Y, McGee C, Ishida-Yamamoto A, Uitto J, Klement JF. Periplakin gene targeting reveals a constituent of the cornified cell envelope dispensable for normal mouse development. Mol Cell Biol 2004; 24:6410-8. [PMID: 15226441 PMCID: PMC434234 DOI: 10.1128/mcb.24.14.6410-6418.2004] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The members of the plakin family of proteins serve as epidermal cytolinkers and components of cell-cell and cell-matrix adhesion complexes, i.e., desmosomes and hemidesmosomes, respectively. Periplakin is a recently characterized member of this family. Human and mouse periplakin genomic loci are conserved, and the proteins are highly homologous, suggesting a role for periplakin in vertebrate physiology. In order to evaluate the functional role of periplakin, we generated periplakin null mice through targeted homologous recombination of mouse embryonic stem cells, followed by development of Ppl(-/-) mice. Mice homozygous for the targeted allele were born in the expected Mendelian frequency, developed normally, possessed grossly normal epidermis and hair, and were healthy and fertile. The epidermal barrier appeared to develop normally during fetal days E15.5 to E16.5, and the cornified envelope and desmosomes in the newborn mice were ultrastructurally normal. No compensatory increase in the expression of other epithelial proteins was detected in the neonatal mouse epidermis lacking periplakin. Consequently, the primary role of periplakin may not relate to the physiology of the cornified cell envelope in epidermal keratinocytes but may reside in the challenges, which normal laboratory mice do not encounter.
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Affiliation(s)
- Sirpa Aho
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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8
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Beekman JM, Bakema JE, van de Winkel JGJ, Leusen JHW. Direct interaction between FcgammaRI (CD64) and periplakin controls receptor endocytosis and ligand binding capacity. Proc Natl Acad Sci U S A 2004; 101:10392-7. [PMID: 15229321 PMCID: PMC478582 DOI: 10.1073/pnas.0401217101] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2004] [Indexed: 11/18/2022] Open
Abstract
FcgammaRI depends for its biological function on both the intracellular domain of the alpha-chain and associated Fc receptor (FcR) gamma-chains. However, functional protein effectors of FcgammaRI's intracellular domain have not been identified. In this study, we identified periplakin (PPL) as a selective interacting protein for the intracellular tail of FcgammaRI but no other activatory FcRs. The interaction was confirmed by coimmunoprecipitation and blot-overlay assays. PPL and FcgammaRI colocalized at the plasma membrane in monocytes and cell transfectants, and both were up-regulated by IFN-gamma. By expressing C-terminal PPL in transfectants, we established a pivotal role for this protein in FcgammaRI ligand binding, endocytosis, and antigen presentation. These data illustrate that intracellular protein interactions with a multisubunit FcR alpha-chain can confer unique properties to the receptor.
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Affiliation(s)
- Jeffrey M Beekman
- Immunotherapy Laboratory, Department of Immunology, University Medical Center Utrecht, 3584 EA, Utrecht, The Netherlands
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9
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Kalinin AE, Idler WW, Marekov LN, McPhie P, Bowers B, Steinert PM, Steven AC. Co-assembly of Envoplakin and Periplakin into Oligomers and Ca2+-dependent Vesicle Binding. J Biol Chem 2004; 279:22773-80. [PMID: 15033990 DOI: 10.1074/jbc.m313660200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Plakin family members envoplakin and periplakin have been shown to be part of the cornified cell envelope in terminally differentiating stratified squamous epithelia. In the present study, purified recombinant human envoplakin and periplakin were used to investigate their properties and interactions. We found that envoplakin was insoluble at physiological conditions in vitro, and co-assembly with periplakin was required for its solubility. Envoplakin and periplakin formed soluble complexes with equimolar stoichiometry. Chemical cross-linking revealed that the major soluble form of all periplakin constructs and of envoplakin/periplakin rod domains was a dimer, although co-assembly of the full-length proteins resulted in formation of higher order oligomers. Electron microscopy of rotary-shadowed periplakin demonstrated thin flexible molecules with an average contour length of 88 nm for the rod-plus-tail fragment, and immunolabeling EM confirmed the molecule as a parallel, in-register, dimer. Both periplakin and envoplakin/periplakin oligomers were able to bind synthetic lipid vesicles whose composition mimicked the cytoplasmic side of the plasma membrane of eukaryotic cells. This binding was dependent on anionic phospholipids and Ca(2+). These findings raise the possibility that envoplakin and periplakin bind to the plasma membrane upon elevation of intracellular [Ca(2+)] in differentiating keratinocytes, where they serve as a scaffold for cornified cell envelope assembly.
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Affiliation(s)
- Andrey E Kalinin
- Laboratory of Skin Biology and Laboratory of Structural Biology, NIAMS, National Institutes of Health, Bethesda, Maryland 20892, USA.
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10
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Okumura M, Yamakawa H, Ohara O, Owaribe K. Novel alternative splicings of BPAG1 (bullous pemphigoid antigen 1) including the domain structure closely related to MACF (microtubule actin cross-linking factor). J Biol Chem 2002; 277:6682-7. [PMID: 11751855 DOI: 10.1074/jbc.m109209200] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BPAG1 (bullous pemphigoid antigen 1) was originally identified as a 230-kDa hemidesmosomal protein and belongs to the plakin family, because it consists of a plakin domain, a coiled-coil rod domain and a COOH-terminal intermediate filament binding domain. To date, alternatively spliced products of BPAG1, BPAG1e, and BPAG1n are known. BPAG1e is expressed in epithelial tissues and localized to hemidesmosomes, on the other hand, BPAG1n is expressed in neural tissues and muscles and has an actin binding domain at the NH(2)-terminal of BPAG1e. BPAG1 is also known as a gene responsible for Dystonia musculorum (dt) neurodegeneration syndrome of the mouse. Another plakin family protein MACF (microtubule actin cross-linking factor) has also an actin binding domain and the plakin domain at the NH(2)-terminal. However, in contrast to its high homology with BPAG1 at the NH(2)-terminal, the COOH-terminal structure of MACF, including a microtubule binding domain, resembles dystrophin rather than plakins. Here, we investigated RNAs and proteins expressed from the BPAG1 locus and suggest novel alternative splicing variants, which include one consisting of the COOH-terminal domain structure homologous to MACF. The results indicate that BPAG1 has three kinds of cytoskeletal binding domains and seems to play an important role in linking the different types of cytoskeletons.
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Affiliation(s)
- Masayo Okumura
- Unit of Biosystems, Graduate School of Human Informatics, Nagoya University, Nagoya 464-8601, Japan.
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11
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Abstract
Envoplakin, a member of the plakin family of proteins, is a component of desmosomes and the epidermal cornified envelope. To understand how envoplakin expression is regulated, we have analyzed the structure of the mouse envoplakin gene and characterized the promoters of both the human and mouse genes. The mouse gene consists of 22 exons and maps to chromosome 11E1, syntenic to the location of the human gene on 17q25. The exon-intron structure of the mouse envoplakin gene is common to all members of the plakin family: the N-terminal protein domain is encoded by 21 small exons, and the central rod domain and the C-terminal globular domain are coded by a single large exon. The C terminus shows the highest sequence conservation between mouse and human envoplakins and between envoplakin and the other family members. The N terminus is also conserved, with sequence homology extending to Drosophila Kakapo. A region between nucleotides -101 and 288 was necessary for promoter activity in transiently transfected primary keratinocytes. This region is highly conserved between the human and mouse genes and contains at least two different positively acting elements identified by site-directed mutagenesis and electrophoretic mobility shift assays. Mutation of a GC box binding Sp1 and Sp3 proteins or a combined E box and Krüppel-like element interacting with unidentified nuclear proteins virtually abolished promoter activity. 600 base pairs of the mouse upstream sequence was sufficient to drive expression of a beta-galactosidase reporter gene in the suprabasal layers of epidermis, esophagus, and forestomach of transgenic mice. Thus, we have identified a regulatory region in the envoplakin gene that can account for the expression pattern of the endogenous protein in stratified squamous epithelia.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Cells, Cultured
- Chromosome Mapping
- Cloning, Molecular
- Conserved Sequence
- DNA, Complementary/metabolism
- Epidermis/metabolism
- Exons
- Gene Expression Regulation
- Genes, Reporter
- Humans
- In Situ Hybridization, Fluorescence
- Introns
- Keratinocytes
- Membrane Proteins/biosynthesis
- Membrane Proteins/chemistry
- Membrane Proteins/genetics
- Mice
- Mice, Transgenic
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Promoter Regions, Genetic
- Protein Precursors/biosynthesis
- Protein Precursors/chemistry
- Protein Precursors/genetics
- Protein Structure, Tertiary
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Transfection
- beta-Galactosidase/metabolism
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Affiliation(s)
- A Määttä
- Keratinocyte Laboratory, Imperial Cancer Research Fund, 44 Lincoln's Inn Fields, London WC2A 3PX, United Kingdom
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12
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Aho S, Buisson M, Pajunen T, Ryoo YW, Giot JF, Gruffat H, Sergeant A, Uitto J. Ubinuclein, a novel nuclear protein interacting with cellular and viral transcription factors. J Cell Biol 2000; 148:1165-76. [PMID: 10725330 PMCID: PMC2174308 DOI: 10.1083/jcb.148.6.1165] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The major target tissues for Epstein-Barr virus (EBV) infection are B lymphocytes and epithelial cells of the oropharyngeal zone. The product of the EBV BZLF1 early gene, EB1, a member of the basic leucine-zipper family of transcription factors, interacts with both viral and cellular promoters and transcription factors, modulating the reactivation of latent EBV infection. Here, we characterize a novel cellular protein interacting with the basic domains of EB1 and c-Jun, and competing of their binding to the AP1 consensus site. The transcript is present in a wide variety of human adult, fetal, and tumor tissues, and the protein is detected in the nuclei throughout the human epidermis and as either grainy or punctuate nuclear staining in the cultured keratinocytes. The overexpression of tagged cDNA constructs in keratinocytes revealed that the NH(2) terminus is essential for the nuclear localization, while the central domain is responsible for the interaction with EB1 and for the phenotype of transfected keratinocytes similar to terminal differentiation. The gene was identified in tail-to-tail orientation with the periplakin gene (PPL) in human chromosome 16p13.3 and in a syntenic region in mouse chromosome 16. We designated this novel ubiquitously expressed nuclear protein as ubinuclein and the corresponding gene as UBN1.
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Affiliation(s)
- S Aho
- Department of Dermatology, Jefferson Medical College, and Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA. sirpa@
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13
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Green KJ, Guy SG, Cserhalmi-Friedman PB, McLean WH, Christiano AM, Wagner RM. Analysis of the desmoplakin gene reveals striking conservation with other members of the plakin family of cytolinkers. Exp Dermatol 1999; 8:462-70. [PMID: 10597135 DOI: 10.1111/j.1600-0625.1999.tb00304.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Members of the plakin family of cytolinker proteins integrate filaments into cellular networks and anchor these networks to the plasma membrane. Their importance is supported by the existence of cell and tissue fragility disorders caused by mutations in certain family members. In this study, the human gene encoding desmoplakin (DSP) was characterized and its structure compared with the related family members: plectin, bullous pemphigoid antigen 1 (BPAG1), envoplakin (EVPL) and periplakin (PPL). Sequence analysis of genomic clones was carried out in combination with a PCR-based strategy to define intron-exon borders. DSP was mapped using the GB4 radiation hybrid mapping panel to the interval between markers D6S296 and AFM043 x f2, corresponding to cytogenetic band 6p24. In addition, the murine gene (Dsp) was mapped to mouse chromosome 13 by interspecific backcross mapping. DSP encompasses approximately 45 kb organized into 24 exons and 23 introns, and the pattern of intron-exon borders bears a striking resemblance to other members of the plakin family. Notable features include the fact that a single large exon encodes the entire C-terminus of each gene. In contrast, the N-termini comprise numerous smaller exons with conservation of many intron-exon borders. Detailed characterization and mapping of these genes will facilitate their further evaluation as targets of genetic disorders and provide insights into the evolutionary relationships among molecules in this emerging gene family.
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Affiliation(s)
- K J Green
- Department of Pathology, R. H. Lurie Cancer Center, Northwestern University Medical School, Chicago, IL 60611, USA.
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