The Experts below are selected from a list of 735 Experts worldwide ranked by ideXlab platform
Anil B Mukherjee - One of the best experts on this subject based on the ideXlab platform.
-
Uteroglobin a steroid inducible immunomodulatory protein that founded the secretoglobin superfamily
Endocrine Reviews, 2007Co-Authors: Anil B Mukherjee, Zhongjian Zhang, Beverly S ChiltonAbstract:Blastokinin or Uteroglobin (UG) is a steroid-inducible, evolutionarily conserved, secreted protein that has been extensively studied from the standpoint of its structure and molecular biology. However, the physiological function(s) of UG still remains elusive. Isolated from the uterus of rabbits during early pregnancy, UG is the founding member of a growing superfamily of proteins called Secretoglobin (Scgb). NumerousstudiesdemonstratedthatUGisamultifunctionalprotein with antiinflammatory/ immunomodulatory properties. It inhibits soluble phospholipase A2 activity and binds and perhaps sequesters hydrophobic ligands such as progesterone, retinols, polychlorinated biphenyls, phospholipids, and prostaglandins. In addition to its antiinflammatory activities, UG manifests antichemotactic, antiallergic, antitumorigenic, and embryonic growth-stimulatory activities. The tissue-specific expression of the UG gene is regulated by several steroid hormones, although a nonsteroid hormone, prolactin, further augments its expression in the uterus. The mucosal epithelia of virtually all organs that communicate with the external environment express UG, and it is present in the blood, urine, and other body fluids. Although the physiological functions of this protein are still under investigation, a single nucleotide polymorphism in the UG gene appears to be associated with several inflammatory/autoimmune diseases. Investigations with UG-knockout mice revealed that the absence of this protein leads to phenotypes that suggest its critical homeostatic role(s) against oxidative damage, inflammation, autoimmunity, and cancer. Recent studies on UG-binding proteins (receptors) provide further insight into the multifunctional nature of this protein. Based on its antiinflammatory and antiallergic properties, UG is a potential drug target. (Endocrine Reviews 28: 707–725, 2007)
-
Uteroglobin represses allergen induced inflammatory response by blocking pgd2 receptor mediated functions
Journal of Experimental Medicine, 2004Co-Authors: Asim K Mandal, Zhongjian Zhang, Rabindranath Ray, Moonsuk S Choi, Bhabadeb Chowdhury, N Pattabiraman, Anil B MukherjeeAbstract:Uteroglobin (UG) is an antiinflammatory protein secreted by the epithelial lining of all organs communicating with the external environment. We reported previously that UG-knockout mice manifest exaggerated inflammatory response to allergen, characterized by increased eotaxin and Th2 cytokine gene expression, and eosinophil infiltration in the lungs. In this study, we uncovered that the airway epithelia of these mice also express high levels of cyclooxygenase (COX)-2, a key enzyme for the production of proinflammatory lipid mediators, and the bronchoalveolar lavage fluid (BALF) contain elevated levels of prostaglandin D2. These effects are abrogated by recombinant UG treatment. Although it has been reported that prostaglandin D2 mediates allergic inflammation via its receptor, DP, neither the molecular mechanism(s) of DP signaling nor the mechanism by which UG suppresses DP-mediated inflammatory response are clearly understood. Here we report that DP signaling is mediated via p38 mitogen–activated protein kinase, p44/42 mitogen–activated protein kinase, and protein kinase C pathways in a cell type–specific manner leading to nuclear factor–κB activation stimulating COX-2 gene expression. Further, we found that recombinant UG blocks DP-mediated nuclear factor–κB activation and suppresses COX-2 gene expression. We propose that UG is an essential component of a novel innate homeostatic mechanism in the mammalian airways to repress allergen-induced inflammatory responses.
-
Uteroglobin is essential in preventing immunoglobulin a nephropathy in mice
Nature Medicine, 1999Co-Authors: Feng Zheng, Gopal C Kundu, Zhongjian Zhang, Jerrold M Ward, Francesco J Demayo, Anil B MukherjeeAbstract:The molecular mechanism(s) of immunoglobulin A (IgA) nephropathy, the most common primary renal glomerular disease worldwide, is unknown. Its pathologic features include hematuria, high levels of circulating IgA-fibronectin (Fn) complexes, and glomerular deposition of IgA, complement C3, Fn and collagen. We report here that two independent mouse models (gene knockout and antisense transgenic), both manifesting deficiency of an anti-inflammatory protein, Uteroglobin (UG), develop almost all of the pathologic features of human IgA nephropathy. We further demonstrate that Fn-UG heteromerization, reported to prevent abnormal glomerular deposition of Fn and collagen, also abrogates both the formation of IgA-Fn complexes and their binding to glomerular cells. Moreover, UG prevents glomerular accumulation of exogenous IgA in UG-null mice. These results define an essential role for UG in preventing mouse IgA nephropathy and warrant further studies to determine if a similar mechanism(s) underlies the human disease.
-
Uteroglobin ug suppresses extracellular matrix invasion by normal and cancer cells that express the high affinity ug binding proteins
Journal of Biological Chemistry, 1998Co-Authors: Gopal C Kundu, Zhongjian Zhang, Asim K Mandal, Giuditta Mantileselvaggi, Anil B MukherjeeAbstract:Abstract Uteroglobin (UG) is a steroid-inducible, multifunctional, secreted protein with antiinflammatory and antichemotactic properties. Recently, we have reported a high affinity UG-binding protein (putative receptor), on several cell types, with an apparent molecular mass of 190 kDa (Kundu, G. C., Mantile, G., Miele, L., Cordella-Miele, E., and Mukherjee, A. B. (1996) Proc. Natl. Acad. Sci. U. S. A. 93, 2915–2919). Since UG is a homodimer in which the 70 amino acid subunits are connected by two disulfide bonds, we sought to determine whether UG monomers also interact with the 190-kDa UG-binding protein and if so, whether it has the same biological activity as the dimer. Surprisingly, we discovered that in addition to the 190-kDa species, another protein, with an apparent molecular mass of 49 kDa, binds reduced UG with high affinity and specificity. Both 49- and 190-kDa proteins are readily detectable on nontransformed NIH 3T3 and some murine cancer cells (e.g. mastocytoma, sarcoma, and lymphoma), while lacking on others (e.g. fibrosarcoma). Most interestingly, pretreatment of the cells, which express the binding proteins, with reduced UG dramatically suppresses extracellular matrix (ECM) invasion, when such treatment had no effect on fibrosarcoma cells that lack the UG-binding proteins. Tissue-specific expression studies confirmed that while both 190- and 49-kDa UG-binding proteins are present in bovine heart, spleen, and the liver, only the 190-kDa protein is detectable in the trachea and in the lung. Neither the 190-kDa nor the 49-kDa protein was detectable in the aorta. Purification of these binding proteins from bovine spleen by UG-affinity chromatography and analysis by SDS-polyacrylamide gel electrophoresis followed by silver staining identified two protein bands with apparent molecular masses of 40 and 180 kDa, respectively. Treatment of the NIH 3T3 cells with specific cytokines (i.e. interleukin-6) and other agonists (i.e.lipopolysaccharide) caused a substantially increased level of125I-UG binding but the same cells, when treated with platelet-derived growth factor, tumor necrosis factor-α, interferon-γ, and phorbol 12-myristate 13-acetate, did not alter the UG binding. Taken together, these findings raise the possibility that UG, through its binding proteins, plays critical roles in the regulation of cellular motility and ECM invasion.
-
tissue specific expression of the gene coding for human clara cell 10 kd protein a phospholipase a2 inhibitory protein
Journal of Clinical Investigation, 1993Co-Authors: Alessandro Peri, Eleonora Cordellamiele, Lucio Miele, Anil B MukherjeeAbstract:Clara cell 10-kD protein (cclOkD), asecretory phospholipase A2inhibitor, issuggested tobethehumancounterpart ofrabbit Uteroglobin (UG).Because cc10kD isexpressed constitutively ataveryhigh level inthehumanrespiratory epithelium, the5' region ofitsgenemaybeuseful inachieving organ-specific expression ofrecombinant DNA ingenetherapy ofdiseases such ascystic fibrosis. However, itisimportant toestablish the tissue-specific expression ofthis genebefore designing gene transfer experiments. Since theUG geneintherabbit isexpressed inmanyother organs besides thelung andtheendometrium, weinvestigated theorgan andtissue specificity ofhuman cc10kD geneexpression using polymerase chain reaction, nucleotide sequence analysis, immunofluorescence, andNorthern blotting. Ourresults indicate that, inaddition tothelung, cclOkD isexpressed inseveral nonrespiratory organs, with a distribution pattern verysimilar, ifnotidentical, tothat ofUG intherabbit. Theseresults underscore thenecessity formore detailed analyses ofthe5'region ofthehumancc10kD gene before its usefulness ingenetherapy could befully assessed. Thesedataalso suggest that cc10kD andUGmayhavesimilar physiological function(s). (J.Clin. Invest. 1993. 92:20992109.) Keywords: Clara cell 10-kDprotein *Uteroglobin . mRNA*geneexpression *tissue distribution
Shioko Kimura - One of the best experts on this subject based on the ideXlab platform.
-
ugrp1 a Uteroglobin clara cell secretory protein related protein is a novel lung enriched downstream target gene for the t ebp nkx2 1 homeodomain transcription factor
Molecular Endocrinology, 2001Co-Authors: Tomoaki Niimi, Nicholas C. Popescu, Catherine L Keckwaggoner, Yuhong Zhou, Roy C Levitt, Shioko KimuraAbstract:A novel gene that is down-regulated in lungs of T/ebp/Nkx2.1-null mouse embryos has been identified using a suppressive-subtractive hybridization method. The gene product is a secreted protein, forms a homodimer, and exhibits an amino acid sequence similar to that seen in the Uteroglobin/Clara cell secretory protein family of proteins. This gene, designated Ugrp1 (Uteroglobin-related protein 1), consists of three exons and two introns and produces three transcripts by alternative splicing. The Ugrp1 gene was localized by fluorescence in situ hybridization to mouse chromosome 18 at region 18C-D; this region is homologous with human 5q31-34, where one of the asthma susceptibility genes has been assigned. UGRP1 mRNA is predominantly expressed in the lung, with low levels of expression in the thyroid. Expression in the lung is detectable as early as embryonic day 12.5 and increases markedly by embryonic day 16.5. In T/ebp/Nkx2.1-null embryo lungs, UGRP1 expression was significantly reduced as assessed by RT-P...
-
ugrp1 a Uteroglobin clara cell secretory protein related protein is a novel lung enriched downstream target gene for the t ebp nkx2 1 homeodomain transcription factor
Molecular Endocrinology, 2001Co-Authors: Tomoaki Niimi, Nicholas C. Popescu, Catherine L Keckwaggoner, Yuhong Zhou, Roy C Levitt, Shioko KimuraAbstract:A novel gene that is down-regulated in lungs of T/ebp/Nkx2.1-null mouse embryos has been identified using a suppressive-subtractive hybridization method. The gene product is a secreted protein, forms a homodimer, and exhibits an amino acid sequence similar to that seen in the Uteroglobin/Clara cell secretory protein family of proteins. This gene, designated Ugrp1 (Uteroglobin-related protein 1), consists of three exons and two introns and produces three transcripts by alternative splicing. The Ugrp1 gene was localized by fluorescence in situ hybridization to mouse chromosome 18 at region 18C-D; this region is homologous with human 5q31-34, where one of the asthma susceptibility genes has been assigned. UGRP1 mRNA is predominantly expressed in the lung, with low levels of expression in the thyroid. Expression in the lung is detectable as early as embryonic day 12.5 and increases markedly by embryonic day 16.5. In T/ebp/Nkx2.1-null embryo lungs, UGRP1 expression was significantly reduced as assessed by RT-PCR analysis. Cotransfection assays using a T/EBP/NKX2.1 expression construct with Ugrp1 promoter-luciferase reporter constructs confirmed that T/EBP/NKX2.1 regulates Ugrp1 gene activity at the transcriptional level. Thus, Ugrp1 is a downstream target gene for the T/EBP/NKX2.1 homeodomain transcription factor. Changes in UGRP1 mRNA levels in lungs from antigen-sensitized mice suggest the possible involvement of UGRP1 in inflammation.
-
claudin 18 a novel downstream target gene for the t ebp nkx2 1 homeodomain transcription factor encodes lung and stomach specific isoforms through alternative splicing
Molecular and Cellular Biology, 2001Co-Authors: Tomoaki Niimi, Drazen B. Zimonjic, Nicholas C. Popescu, Jerrold M Ward, Kunio Nagashima, Parviz Minoo, Shioko KimuraAbstract:T/EBP/NKX2.1, also known as TTF-1, is a homeodomain-containing transcription factor that is expressed in lung, thyroid, and a part of the brain (15, 21, 22, 28). T/EBP/NKX2.1 was originally characterized as a transcription factor that regulates expression of thyroid-specific genes such as those encoding thyroglobulin (7), thyroid peroxidase (7, 11, 20), TSH receptor (6, 37), and the Na/I symporter (10). In the lung, T/EBP/NKX2.1 is expressed in all epithelial cells early during pulmonary morphogenesis, but the expression becomes progressively restricted to alveolar type II and Clara cells towards the end of gestation and in postnatal days (46). T/EBP/NKX2.1 activates transcription of genes specifically expressed in lung, including the genes for surfactant proteins A (2), B (1), and C (19) and Clara cell secretory protein (also called Uteroglobin) genes (34, 35). Targeted disruption of the T/ebp/Nkx2.1 locus was shown to result in immediate postnatal death due to respiratory failure caused by profoundly hypoplastic lungs (21, 26). These mice also lack the thyroid, pituitary, and parts of the ventral forebrain such as the hypothalamus and basal ganglia (21, 41, 42). Detailed analyses of the T/ebp/Nkx2.1-null mouse respiratory system revealed that T/EBP/NKX2.1 may function in the establishment of pattern formation of early pulmonary structure and pulmonary morphogenesis during embryonic development (26). A role for T/EBP/NKX2.1 in pulmonary morphogenesis was also suggested by in vitro experiments in which a T/EBP/NKX2.1 antisense oligonucleotide inhibited normal branching morphogenesis in lung organ culture (25). Based on these results, it is hypothesized that lung branching morphogenesis must be related to the ability of T/EBP/NKX2.1 to activate and/or suppress specific downstream target genes. One such category of target genes in lung consists of the surfactant proteins A (2), B (1), and C (19) and Clara cell secretory protein genes (34, 35). However, they are not known to have morphoregulatory function. Extensive studies have shown that epithelial-mesenchymal interaction plays an instructive role in lung branching morphogenesis (3, 17, 24, 45). In this context, a possible function for T/EBP/NKX2.1 may be in activation of epithelial cell pathways that are necessary for receiving and/or interpreting the instructive signals that originate from the mesenchyme. In this role, downstream target genes for T/EBP/NKX2.1 would potentially include those encoding cell surface receptors, components of the signal transduction pathway, and/or a variety of other factors connecting the cell surface to changes in gene expression and cellular behavior. In T/ebp/Nkx2.1-null embryo lungs, expression of some extracellular matrix proteins and their cellular receptors, including collagen type IV and α integrins, and some growth factors such as VEGF3 and BMP4 is reduced or absent (46). Whether the abnormal phenotype in T/ebp/Nkx2.1-null embryo lungs is entirely or partially due to the reduction or absence of expression of these genes remains to be examined. Among possible target genes are those encoding elements of tight junctions (TJs), a specialized membrane domain at the most apical region of polarized epithelial cells that creates a primary barrier to prevent paracellular transport of solutes and restrict the lateral diffusion of membrane lipids and proteins to maintain cellular polarity (4, 5, 23, 27, 40, 44). Claudins, products of a recently identified multigene family, are components of TJ strands and have four transmembrane domains and two extracellular loops with both NH2 and COOH termini in the cytoplasm (29, 43). Claudins have several functional characteristics consistent with a role in barrier formation and dependent on the specific claudin species that exhibit tissue specificity (27, 29). Claudin-1 and -2 have the ability to induce the formation of networks of strands and grooves at cell-cell contact sites when introduced into fibroblasts lacking TJs (12). Both claudin-3 and -4 are receptors for a cytotoxic enterotoxin (CPE) produced by the bacterium Clostridium perfringens, and the interaction with CPE results in increased membrane permeability by forming small pores in plasma membrane (39). A claudin-11 (oligodendrocyte-specific protein) knockout mouse showed the absence of TJ strands in central nervous system myelin and Sertoli cells in testis (14). Mutations in human claudin-16 (paracellin-1) cause renal hypomagnesemia with hypercalciuria and nephrocalcinosis, suggesting that it creates a channel that allows magnesium to diffuse through renal TJs (38). To date, at least 20 members of the claudin gene family have been identified (27). However, many of these claudins have not yet been examined in detail, and the functional differences are largely unknown. Here, we isolated and characterized a novel member of claudin gene family, claudin-18, which has two isoform transcripts produced by alternative splicing that exhibit lung- and stomach-specific expression. Further, claudin-18 has a splicing variant lacking the C-terminal cytoplasmic domain. Analysis of the promoter function of the mouse claudin-18 gene suggests that the lung-specific form is a downstream target gene regulated by the T/EBP/NKX2.1 homeodomain transcription factor.
Lucio Miele - One of the best experts on this subject based on the ideXlab platform.
-
Uteroglobin a possible ligand of the lipoxin receptor inhibits serum amyloid a driven inflammation
Mediators of Inflammation, 2014Co-Authors: Giovanni Antico, Lucio Miele, Monica Aloman, Katja Lakota, Stefano Fiore, Snezna SodinsemrlAbstract:Serum amyloid A (SAA) production is increased by inflamed arthritic synovial tissue, where it acts as a cytokine/chemoattractant for inflammatory and immune cells and as an inducer of matrix degrading enzymes. SAA has been shown to bind lipoxin A4 receptor, a member of the formyl-peptide related 2 G-protein coupled receptor family (ALX) and elicit proinflammatory activities in human primary fibroblast-like synoviocytes (FLS). We report on the identification of Uteroglobin, a small globular protein with potent anti-inflammatory activities, as a possible ligand of ALX. Uteroglobin-specific association with ALX was demonstrated by an enzyme immunoassay experiment employing a cell line engineered to express the human ALX receptor. Uteroglobin's interaction with ALX resulted in the inhibition of SAA responses, such as attenuation of phospholipase A2 activation and cellular chemotaxis. In FLS, Uteroglobin showed an antagonism against SAA-induced interleukin-8 release and decreased cell migration. These novel roles described for Uteroglobin via ALX may help elucidate genetic and clinical observations indicating that a polymorphism in the Uteroglobin promoter is linked to disease outcome, specifically prediction of bone erosion in patients with rheumatoid arthritis or severity of IgA glomerulonephritis and sarcoidosis.
-
tissue specific expression of the gene coding for human clara cell 10 kd protein a phospholipase a2 inhibitory protein
Journal of Clinical Investigation, 1993Co-Authors: Alessandro Peri, Eleonora Cordellamiele, Lucio Miele, Anil B MukherjeeAbstract:Clara cell 10-kD protein (cclOkD), asecretory phospholipase A2inhibitor, issuggested tobethehumancounterpart ofrabbit Uteroglobin (UG).Because cc10kD isexpressed constitutively ataveryhigh level inthehumanrespiratory epithelium, the5' region ofitsgenemaybeuseful inachieving organ-specific expression ofrecombinant DNA ingenetherapy ofdiseases such ascystic fibrosis. However, itisimportant toestablish the tissue-specific expression ofthis genebefore designing gene transfer experiments. Since theUG geneintherabbit isexpressed inmanyother organs besides thelung andtheendometrium, weinvestigated theorgan andtissue specificity ofhuman cc10kD geneexpression using polymerase chain reaction, nucleotide sequence analysis, immunofluorescence, andNorthern blotting. Ourresults indicate that, inaddition tothelung, cclOkD isexpressed inseveral nonrespiratory organs, with a distribution pattern verysimilar, ifnotidentical, tothat ofUG intherabbit. Theseresults underscore thenecessity formore detailed analyses ofthe5'region ofthehumancc10kD gene before its usefulness ingenetherapy could befully assessed. Thesedataalso suggest that cc10kD andUGmayhavesimilar physiological function(s). (J.Clin. Invest. 1993. 92:20992109.) Keywords: Clara cell 10-kDprotein *Uteroglobin . mRNA*geneexpression *tissue distribution
-
tissue specific expression of the gene coding for human clara cell 10 kd protein a phospholipase a2 inhibitory protein
Journal of Clinical Investigation, 1993Co-Authors: Alessandro Peri, Eleonora Cordellamiele, Lucio Miele, Anil B MukherjeeAbstract:Clara cell 10-kD protein (cc10kD), a secretory phospholipase A2 inhibitor, is suggested to be the human counterpart of rabbit Uteroglobin (UG). Because cc10kD is expressed constitutively at a very high level in the human respiratory epithelium, the 5' region of its gene may be useful in achieving organ-specific expression of recombinant DNA in gene therapy of diseases such as cystic fibrosis. However, it is important to establish the tissue-specific expression of this gene before designing gene transfer experiments. Since the UG gene in the rabbit is expressed in many other organs besides the lung and the endometrium, we investigated the organ and tissue specificity of human cc10kD gene expression using polymerase chain reaction, nucleotide sequence analysis, immunofluorescence, and Northern blotting. Our results indicate that, in addition to the lung, cc10kD is expressed in several nonrespiratory organs, with a distribution pattern very similar, if not identical, to that of UG in the rabbit. These results underscore the necessity for more detailed analyses of the 5' region of the human cc10kD gene before its usefulness in gene therapy could be fully assessed. These data also suggest that cc10kD and UG may have similar physiological function(s).
-
human clara cell 10 kda protein is the counterpart of rabbit Uteroglobin
Journal of Biological Chemistry, 1993Co-Authors: Giuditta Mantile, Eleonora Cordellamiele, Lucio Miele, Sikandar L Katyal, Gurmukh Singh, Anil B MukherjeeAbstract:Abstract Human Clara cell 10-kDa protein has been suggested to be a counterpart of rabbit Uteroglobin, an immunomodulatory and antiinflammatory secretory protein. Since this human protein is not readily available in substantial quantity for detailed characterization of its biochemical, biological, and pharmacological properties, we sought to express it in Escherichia coli in order to study its structure-function relationship. However, bacterial overproduction of homodimeric proteins with interchain disulfide bonds, such as Clara cell 10-kDa protein, was thought to be impossible until we achieved expression of native Uteroglobin (Miele, L., Cordella-Miele, E., and Mukherjee, A.B. (1990) J. Biol. Chem. 265, 6427-6435). Here, we report high level production of recombinant native dimeric human Clara cell 10-kDa protein in E. coli and its characterization. Recombinant human Clara cell 10-kDa protein forms its disulfide bonds within the bacterial cytoplasm. The purified protein possesses two of the most important activities characteristic of Uteroglobin: (i) it is an excellent substrate of transglutaminase, and (ii) it is a potent inhibitor of porcine pancreatic and, more importantly, human synovial phospholipase A2. These results demonstrate that human Clara cell 10-kDa protein and rabbit Uteroglobin have very similar biochemical properties. Our data suggest that this protein may possess immunomodulatory and antiinflammatory activities of potential physiological and pharmacological importance.
Nicholas C. Popescu - One of the best experts on this subject based on the ideXlab platform.
-
ugrp1 a Uteroglobin clara cell secretory protein related protein is a novel lung enriched downstream target gene for the t ebp nkx2 1 homeodomain transcription factor
Molecular Endocrinology, 2001Co-Authors: Tomoaki Niimi, Nicholas C. Popescu, Catherine L Keckwaggoner, Yuhong Zhou, Roy C Levitt, Shioko KimuraAbstract:A novel gene that is down-regulated in lungs of T/ebp/Nkx2.1-null mouse embryos has been identified using a suppressive-subtractive hybridization method. The gene product is a secreted protein, forms a homodimer, and exhibits an amino acid sequence similar to that seen in the Uteroglobin/Clara cell secretory protein family of proteins. This gene, designated Ugrp1 (Uteroglobin-related protein 1), consists of three exons and two introns and produces three transcripts by alternative splicing. The Ugrp1 gene was localized by fluorescence in situ hybridization to mouse chromosome 18 at region 18C-D; this region is homologous with human 5q31-34, where one of the asthma susceptibility genes has been assigned. UGRP1 mRNA is predominantly expressed in the lung, with low levels of expression in the thyroid. Expression in the lung is detectable as early as embryonic day 12.5 and increases markedly by embryonic day 16.5. In T/ebp/Nkx2.1-null embryo lungs, UGRP1 expression was significantly reduced as assessed by RT-P...
-
ugrp1 a Uteroglobin clara cell secretory protein related protein is a novel lung enriched downstream target gene for the t ebp nkx2 1 homeodomain transcription factor
Molecular Endocrinology, 2001Co-Authors: Tomoaki Niimi, Nicholas C. Popescu, Catherine L Keckwaggoner, Yuhong Zhou, Roy C Levitt, Shioko KimuraAbstract:A novel gene that is down-regulated in lungs of T/ebp/Nkx2.1-null mouse embryos has been identified using a suppressive-subtractive hybridization method. The gene product is a secreted protein, forms a homodimer, and exhibits an amino acid sequence similar to that seen in the Uteroglobin/Clara cell secretory protein family of proteins. This gene, designated Ugrp1 (Uteroglobin-related protein 1), consists of three exons and two introns and produces three transcripts by alternative splicing. The Ugrp1 gene was localized by fluorescence in situ hybridization to mouse chromosome 18 at region 18C-D; this region is homologous with human 5q31-34, where one of the asthma susceptibility genes has been assigned. UGRP1 mRNA is predominantly expressed in the lung, with low levels of expression in the thyroid. Expression in the lung is detectable as early as embryonic day 12.5 and increases markedly by embryonic day 16.5. In T/ebp/Nkx2.1-null embryo lungs, UGRP1 expression was significantly reduced as assessed by RT-PCR analysis. Cotransfection assays using a T/EBP/NKX2.1 expression construct with Ugrp1 promoter-luciferase reporter constructs confirmed that T/EBP/NKX2.1 regulates Ugrp1 gene activity at the transcriptional level. Thus, Ugrp1 is a downstream target gene for the T/EBP/NKX2.1 homeodomain transcription factor. Changes in UGRP1 mRNA levels in lungs from antigen-sensitized mice suggest the possible involvement of UGRP1 in inflammation.
-
claudin 18 a novel downstream target gene for the t ebp nkx2 1 homeodomain transcription factor encodes lung and stomach specific isoforms through alternative splicing
Molecular and Cellular Biology, 2001Co-Authors: Tomoaki Niimi, Drazen B. Zimonjic, Nicholas C. Popescu, Jerrold M Ward, Kunio Nagashima, Parviz Minoo, Shioko KimuraAbstract:T/EBP/NKX2.1, also known as TTF-1, is a homeodomain-containing transcription factor that is expressed in lung, thyroid, and a part of the brain (15, 21, 22, 28). T/EBP/NKX2.1 was originally characterized as a transcription factor that regulates expression of thyroid-specific genes such as those encoding thyroglobulin (7), thyroid peroxidase (7, 11, 20), TSH receptor (6, 37), and the Na/I symporter (10). In the lung, T/EBP/NKX2.1 is expressed in all epithelial cells early during pulmonary morphogenesis, but the expression becomes progressively restricted to alveolar type II and Clara cells towards the end of gestation and in postnatal days (46). T/EBP/NKX2.1 activates transcription of genes specifically expressed in lung, including the genes for surfactant proteins A (2), B (1), and C (19) and Clara cell secretory protein (also called Uteroglobin) genes (34, 35). Targeted disruption of the T/ebp/Nkx2.1 locus was shown to result in immediate postnatal death due to respiratory failure caused by profoundly hypoplastic lungs (21, 26). These mice also lack the thyroid, pituitary, and parts of the ventral forebrain such as the hypothalamus and basal ganglia (21, 41, 42). Detailed analyses of the T/ebp/Nkx2.1-null mouse respiratory system revealed that T/EBP/NKX2.1 may function in the establishment of pattern formation of early pulmonary structure and pulmonary morphogenesis during embryonic development (26). A role for T/EBP/NKX2.1 in pulmonary morphogenesis was also suggested by in vitro experiments in which a T/EBP/NKX2.1 antisense oligonucleotide inhibited normal branching morphogenesis in lung organ culture (25). Based on these results, it is hypothesized that lung branching morphogenesis must be related to the ability of T/EBP/NKX2.1 to activate and/or suppress specific downstream target genes. One such category of target genes in lung consists of the surfactant proteins A (2), B (1), and C (19) and Clara cell secretory protein genes (34, 35). However, they are not known to have morphoregulatory function. Extensive studies have shown that epithelial-mesenchymal interaction plays an instructive role in lung branching morphogenesis (3, 17, 24, 45). In this context, a possible function for T/EBP/NKX2.1 may be in activation of epithelial cell pathways that are necessary for receiving and/or interpreting the instructive signals that originate from the mesenchyme. In this role, downstream target genes for T/EBP/NKX2.1 would potentially include those encoding cell surface receptors, components of the signal transduction pathway, and/or a variety of other factors connecting the cell surface to changes in gene expression and cellular behavior. In T/ebp/Nkx2.1-null embryo lungs, expression of some extracellular matrix proteins and their cellular receptors, including collagen type IV and α integrins, and some growth factors such as VEGF3 and BMP4 is reduced or absent (46). Whether the abnormal phenotype in T/ebp/Nkx2.1-null embryo lungs is entirely or partially due to the reduction or absence of expression of these genes remains to be examined. Among possible target genes are those encoding elements of tight junctions (TJs), a specialized membrane domain at the most apical region of polarized epithelial cells that creates a primary barrier to prevent paracellular transport of solutes and restrict the lateral diffusion of membrane lipids and proteins to maintain cellular polarity (4, 5, 23, 27, 40, 44). Claudins, products of a recently identified multigene family, are components of TJ strands and have four transmembrane domains and two extracellular loops with both NH2 and COOH termini in the cytoplasm (29, 43). Claudins have several functional characteristics consistent with a role in barrier formation and dependent on the specific claudin species that exhibit tissue specificity (27, 29). Claudin-1 and -2 have the ability to induce the formation of networks of strands and grooves at cell-cell contact sites when introduced into fibroblasts lacking TJs (12). Both claudin-3 and -4 are receptors for a cytotoxic enterotoxin (CPE) produced by the bacterium Clostridium perfringens, and the interaction with CPE results in increased membrane permeability by forming small pores in plasma membrane (39). A claudin-11 (oligodendrocyte-specific protein) knockout mouse showed the absence of TJ strands in central nervous system myelin and Sertoli cells in testis (14). Mutations in human claudin-16 (paracellin-1) cause renal hypomagnesemia with hypercalciuria and nephrocalcinosis, suggesting that it creates a channel that allows magnesium to diffuse through renal TJs (38). To date, at least 20 members of the claudin gene family have been identified (27). However, many of these claudins have not yet been examined in detail, and the functional differences are largely unknown. Here, we isolated and characterized a novel member of claudin gene family, claudin-18, which has two isoform transcripts produced by alternative splicing that exhibit lung- and stomach-specific expression. Further, claudin-18 has a splicing variant lacking the C-terminal cytoplasmic domain. Analysis of the promoter function of the mouse claudin-18 gene suggests that the lung-specific form is a downstream target gene regulated by the T/EBP/NKX2.1 homeodomain transcription factor.
-
identification of mammaglobin b a novel member of the Uteroglobin gene family
Genomics, 1998Co-Authors: Robert M. Becker, Christopher Darrow, Drazen B. Zimonjic, Nicholas C. Popescu, Mark A. Watson, Timothy P. FlemingAbstract:In this report, we have identified, sequenced, and characterized the expression pattern of a novel human gene, mammaglobin B. Mammaglobin B (MGB2) is highly homologous to mammaglobin (MGB1), a previously characterized human gene whose expression is limited to the mammary epithelium and frequently up-regulated in human breast cancer cells. Based upon amino acid sequence similarities, both mammaglobin and mammaglobin B may be considered members of a larger, mammalian multigene family that includes rabbit Uteroglobin, human Clara Cell 10-kDa protein (CC10), and the multimeric rat prostatein protein. Together with the human CC10 gene, mammaglobin and mammaglobin B are closely linked on human chromosome 11q13. However, despite their primary sequence similarity and close chromosomal proximity, the expression of mammaglobin and mammaglobin B is nonconcordant in both nonmalignant and neoplastic tissue.
-
structure and transcriptional regulation of the human mammaglobin gene a breast cancer associated member of the Uteroglobin gene family localized to chromosome 11q13
Oncogene, 1998Co-Authors: Mark A. Watson, Drazen B. Zimonjic, Christopher Darrow, Nicholas C. Popescu, Timothy P. FlemingAbstract:: The mammaglobin gene encodes a novel secreted protein whose corresponding mRNA is frequently up-regulated in human breast cancer. In non-malignant tissues, expression is also strictly limited to the mammary epithelium. To better understand the mechanisms controlling these patterns of expression, we have isolated the human mammaglobin gene and performed an initial assessment of its promoter activity. Mammaglobin gene architecture is very similar to that of a family of related genes that includes Uteroglobin and rat prostatein subunits C1, C2, and C3. However, the mammaglobin gene itself is not well conserved phylogenetically. The human mammaglobin gene is localized by fluorescent in situ hybridization to chromosome 11 band q13, a genomic region frequently amplified in breast neoplasia. The sequence of proximal 1 kb of mammaglobin promoter contains several potential transcriptional control elements and directs high-level expression of a transfected reporter construct in human breast tumor cell lines. However, comparable levels of reporter gene expression are also seen in non-mammary human cell lines. These data suggest that, unlike related gene family members, the striking breast-specific expression and tumor-associated overexpression of mammaglobin is mediated by complex transcriptional control at more distal sequence elements.
Tomoaki Niimi - One of the best experts on this subject based on the ideXlab platform.
-
ugrp1 a Uteroglobin clara cell secretory protein related protein is a novel lung enriched downstream target gene for the t ebp nkx2 1 homeodomain transcription factor
Molecular Endocrinology, 2001Co-Authors: Tomoaki Niimi, Nicholas C. Popescu, Catherine L Keckwaggoner, Yuhong Zhou, Roy C Levitt, Shioko KimuraAbstract:A novel gene that is down-regulated in lungs of T/ebp/Nkx2.1-null mouse embryos has been identified using a suppressive-subtractive hybridization method. The gene product is a secreted protein, forms a homodimer, and exhibits an amino acid sequence similar to that seen in the Uteroglobin/Clara cell secretory protein family of proteins. This gene, designated Ugrp1 (Uteroglobin-related protein 1), consists of three exons and two introns and produces three transcripts by alternative splicing. The Ugrp1 gene was localized by fluorescence in situ hybridization to mouse chromosome 18 at region 18C-D; this region is homologous with human 5q31-34, where one of the asthma susceptibility genes has been assigned. UGRP1 mRNA is predominantly expressed in the lung, with low levels of expression in the thyroid. Expression in the lung is detectable as early as embryonic day 12.5 and increases markedly by embryonic day 16.5. In T/ebp/Nkx2.1-null embryo lungs, UGRP1 expression was significantly reduced as assessed by RT-P...
-
ugrp1 a Uteroglobin clara cell secretory protein related protein is a novel lung enriched downstream target gene for the t ebp nkx2 1 homeodomain transcription factor
Molecular Endocrinology, 2001Co-Authors: Tomoaki Niimi, Nicholas C. Popescu, Catherine L Keckwaggoner, Yuhong Zhou, Roy C Levitt, Shioko KimuraAbstract:A novel gene that is down-regulated in lungs of T/ebp/Nkx2.1-null mouse embryos has been identified using a suppressive-subtractive hybridization method. The gene product is a secreted protein, forms a homodimer, and exhibits an amino acid sequence similar to that seen in the Uteroglobin/Clara cell secretory protein family of proteins. This gene, designated Ugrp1 (Uteroglobin-related protein 1), consists of three exons and two introns and produces three transcripts by alternative splicing. The Ugrp1 gene was localized by fluorescence in situ hybridization to mouse chromosome 18 at region 18C-D; this region is homologous with human 5q31-34, where one of the asthma susceptibility genes has been assigned. UGRP1 mRNA is predominantly expressed in the lung, with low levels of expression in the thyroid. Expression in the lung is detectable as early as embryonic day 12.5 and increases markedly by embryonic day 16.5. In T/ebp/Nkx2.1-null embryo lungs, UGRP1 expression was significantly reduced as assessed by RT-PCR analysis. Cotransfection assays using a T/EBP/NKX2.1 expression construct with Ugrp1 promoter-luciferase reporter constructs confirmed that T/EBP/NKX2.1 regulates Ugrp1 gene activity at the transcriptional level. Thus, Ugrp1 is a downstream target gene for the T/EBP/NKX2.1 homeodomain transcription factor. Changes in UGRP1 mRNA levels in lungs from antigen-sensitized mice suggest the possible involvement of UGRP1 in inflammation.
-
claudin 18 a novel downstream target gene for the t ebp nkx2 1 homeodomain transcription factor encodes lung and stomach specific isoforms through alternative splicing
Molecular and Cellular Biology, 2001Co-Authors: Tomoaki Niimi, Drazen B. Zimonjic, Nicholas C. Popescu, Jerrold M Ward, Kunio Nagashima, Parviz Minoo, Shioko KimuraAbstract:T/EBP/NKX2.1, also known as TTF-1, is a homeodomain-containing transcription factor that is expressed in lung, thyroid, and a part of the brain (15, 21, 22, 28). T/EBP/NKX2.1 was originally characterized as a transcription factor that regulates expression of thyroid-specific genes such as those encoding thyroglobulin (7), thyroid peroxidase (7, 11, 20), TSH receptor (6, 37), and the Na/I symporter (10). In the lung, T/EBP/NKX2.1 is expressed in all epithelial cells early during pulmonary morphogenesis, but the expression becomes progressively restricted to alveolar type II and Clara cells towards the end of gestation and in postnatal days (46). T/EBP/NKX2.1 activates transcription of genes specifically expressed in lung, including the genes for surfactant proteins A (2), B (1), and C (19) and Clara cell secretory protein (also called Uteroglobin) genes (34, 35). Targeted disruption of the T/ebp/Nkx2.1 locus was shown to result in immediate postnatal death due to respiratory failure caused by profoundly hypoplastic lungs (21, 26). These mice also lack the thyroid, pituitary, and parts of the ventral forebrain such as the hypothalamus and basal ganglia (21, 41, 42). Detailed analyses of the T/ebp/Nkx2.1-null mouse respiratory system revealed that T/EBP/NKX2.1 may function in the establishment of pattern formation of early pulmonary structure and pulmonary morphogenesis during embryonic development (26). A role for T/EBP/NKX2.1 in pulmonary morphogenesis was also suggested by in vitro experiments in which a T/EBP/NKX2.1 antisense oligonucleotide inhibited normal branching morphogenesis in lung organ culture (25). Based on these results, it is hypothesized that lung branching morphogenesis must be related to the ability of T/EBP/NKX2.1 to activate and/or suppress specific downstream target genes. One such category of target genes in lung consists of the surfactant proteins A (2), B (1), and C (19) and Clara cell secretory protein genes (34, 35). However, they are not known to have morphoregulatory function. Extensive studies have shown that epithelial-mesenchymal interaction plays an instructive role in lung branching morphogenesis (3, 17, 24, 45). In this context, a possible function for T/EBP/NKX2.1 may be in activation of epithelial cell pathways that are necessary for receiving and/or interpreting the instructive signals that originate from the mesenchyme. In this role, downstream target genes for T/EBP/NKX2.1 would potentially include those encoding cell surface receptors, components of the signal transduction pathway, and/or a variety of other factors connecting the cell surface to changes in gene expression and cellular behavior. In T/ebp/Nkx2.1-null embryo lungs, expression of some extracellular matrix proteins and their cellular receptors, including collagen type IV and α integrins, and some growth factors such as VEGF3 and BMP4 is reduced or absent (46). Whether the abnormal phenotype in T/ebp/Nkx2.1-null embryo lungs is entirely or partially due to the reduction or absence of expression of these genes remains to be examined. Among possible target genes are those encoding elements of tight junctions (TJs), a specialized membrane domain at the most apical region of polarized epithelial cells that creates a primary barrier to prevent paracellular transport of solutes and restrict the lateral diffusion of membrane lipids and proteins to maintain cellular polarity (4, 5, 23, 27, 40, 44). Claudins, products of a recently identified multigene family, are components of TJ strands and have four transmembrane domains and two extracellular loops with both NH2 and COOH termini in the cytoplasm (29, 43). Claudins have several functional characteristics consistent with a role in barrier formation and dependent on the specific claudin species that exhibit tissue specificity (27, 29). Claudin-1 and -2 have the ability to induce the formation of networks of strands and grooves at cell-cell contact sites when introduced into fibroblasts lacking TJs (12). Both claudin-3 and -4 are receptors for a cytotoxic enterotoxin (CPE) produced by the bacterium Clostridium perfringens, and the interaction with CPE results in increased membrane permeability by forming small pores in plasma membrane (39). A claudin-11 (oligodendrocyte-specific protein) knockout mouse showed the absence of TJ strands in central nervous system myelin and Sertoli cells in testis (14). Mutations in human claudin-16 (paracellin-1) cause renal hypomagnesemia with hypercalciuria and nephrocalcinosis, suggesting that it creates a channel that allows magnesium to diffuse through renal TJs (38). To date, at least 20 members of the claudin gene family have been identified (27). However, many of these claudins have not yet been examined in detail, and the functional differences are largely unknown. Here, we isolated and characterized a novel member of claudin gene family, claudin-18, which has two isoform transcripts produced by alternative splicing that exhibit lung- and stomach-specific expression. Further, claudin-18 has a splicing variant lacking the C-terminal cytoplasmic domain. Analysis of the promoter function of the mouse claudin-18 gene suggests that the lung-specific form is a downstream target gene regulated by the T/EBP/NKX2.1 homeodomain transcription factor.
