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Floros J, Tsotakos N. Differential Regulation of Human Surfactant Protein A Genes, SFTPA1 and SFTPA2, and Their Corresponding Variants. Front Immunol 2021; 12:766719. [PMID: 34917085 PMCID: PMC8669794 DOI: 10.3389/fimmu.2021.766719] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 11/02/2021] [Indexed: 11/26/2022] Open
Abstract
The human SFTPA1 and SFTPA2 genes encode the surfactant protein A1 (SP-A1) and SP-A2, respectively, and they have been identified with significant genetic and epigenetic variability including sequence, deletion/insertions, and splice variants. The surfactant proteins, SP-A1 and SP-A2, and their corresponding variants play important roles in several processes of innate immunity as well in surfactant-related functions as reviewed elsewhere [1]. The levels of SP-A have been shown to differ among individuals both under baseline conditions and in response to various agents or disease states. Moreover, a number of agents have been shown to differentially regulate SFTPA1 and SFTPA2 transcripts. The focus in this review is on the differential regulation of SFTPA1 and SFTPA2 with primary focus on the role of 5′ and 3′ untranslated regions (UTRs) and flanking sequences on this differential regulation as well molecules that may mediate the differential regulation.
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Affiliation(s)
- Joanna Floros
- Department of Pediatrics, The Pennsylvania State University College of Medicine, Hershey, PA, United States.,Department of Obstetrics and Gynecology, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Nikolaos Tsotakos
- School of Science, Engineering, and Technology, The Pennsylvania State University - Harrisburg, Middletown, PA, United States
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Vieira F, Kung JW, Bhatti F. Structure, genetics and function of the pulmonary associated surfactant proteins A and D: The extra-pulmonary role of these C type lectins. Ann Anat 2017; 211:184-201. [PMID: 28351530 DOI: 10.1016/j.aanat.2017.03.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Revised: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 10/19/2022]
Abstract
The collectins family encompasses several collagenous Ca2+-dependent defense lectins that are described as pathogen recognition molecules. They play an important role in both adaptive and innate immunity. Surfactant proteins A and D are two of these proteins which were initially discovered in association with surfactant in the pulmonary system. The structure, immune and inflammatory functions, and genetic variations have been well described in relation to their roles, function and pathophysiology in the pulmonary system. Subsequently, these proteins have been discovered in a wide range of other organs and organ systems. The role of these proteins outside the pulmonary system is currently an active area of research. This review intends to provide a current overview of the genetics, structure and extra-pulmonary functions of the surfactant collectin proteins.
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Affiliation(s)
- Frederico Vieira
- Neonatal Perinatal Medicine, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
| | - Johannes W Kung
- Neonatal Perinatal Medicine, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
| | - Faizah Bhatti
- Neonatal Perinatal Medicine, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States; Department of Ophthalmology, Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States; Oklahoma Center for Neurosciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
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MYBPH, a transcriptional target of TTF-1, inhibits ROCK1, and reduces cell motility and metastasis. EMBO J 2011; 31:481-93. [PMID: 22085929 DOI: 10.1038/emboj.2011.416] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2011] [Accepted: 10/18/2011] [Indexed: 11/08/2022] Open
Abstract
Cell migration driven by actomyosin filament assembly is a critical step in tumour invasion and metastasis. Herein, we report identification of myosin binding protein H (MYBPH) as a transcriptional target of TTF-1 (also known as NKX2-1 and TITF1), a master regulator of lung development that also plays a role as a lineage-survival oncogene in lung adenocarcinoma development. MYBPH inhibited assembly competence-conferring phosphorylation of the myosin regulatory light chain (RLC) as well as activating phosphorylation of LIM domain kinase (LIMK), unexpectedly through its direct physical interaction with Rho kinase 1 (ROCK1) rather than with RLC. Consequently, MYBPH inhibited ROCK1 and negatively regulated actomyosin organization, which in turn reduced single cell motility and increased collective cell migration, resulting in decreased cancer invasion and metastasis. Finally, we also show that MYBPH is epigenetically inactivated by promoter DNA methylation in a fraction of TTF-1-positive lung adenocarcinomas, which appears to be in accordance with its deleterious functions in lung adenocarcinoma invasion and metastasis, as well as with the paradoxical association of TTF-1 expression with favourable prognosis in lung adenocarcinoma patients.
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Liu D, Benlhabib H, Mendelson CR. cAMP enhances estrogen-related receptor alpha (ERRalpha) transcriptional activity at the SP-A promoter by increasing its interaction with protein kinase A and steroid receptor coactivator 2 (SRC-2). Mol Endocrinol 2009; 23:772-83. [PMID: 19264843 PMCID: PMC2691680 DOI: 10.1210/me.2008-0282] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Accepted: 02/24/2009] [Indexed: 01/01/2023] Open
Abstract
Estrogen-related receptor (ERRalpha) plays a critical role in basal and cAMP-induced expression of the human surfactant protein-A (SP-A) gene in lung type II cells through direct binding to an ERR response element (ERRE, 5'-TGACCTTA-3') within its 5'-flanking region. Furthermore, protein kinase A (PKA) up-regulates ERRalpha activation of the hSP-A promoter. In the present study, using cultured human fetal lung type II cells, we observed that cAMP enhanced ERRalpha phosphorylation and nuclear expression levels. cAMP/PKA stimulation of ERRalpha activation of the SP-A promoter was blocked by the PKA inhibitor, H89, whereas the MAPK P38 inhibitor, SB203580, and the MAPK kinase inhibitor, PD98059, had negligible to modest effects. This suggests that cAMP acts selectively through PKA to increase ERRalpha transcriptional activity. Of several coactivators tested, steroid receptor coactivator 2 (SRC-2) had the most pronounced effect to increase ERRalpha transcriptional activity at the SP-A promoter; this was enhanced by cotransfection with PKA catalytic subunit (PKAcat). Interestingly, SRC-2, ERRalpha, and PKAcat in type II cell nuclear extracts interacted at the ERRE; this was enhanced by cAMP and inhibited by H89. cAMP increased in vivo binding of PKAcat and SRC-2 to the ERRE genomic region in lung type II cells. In mutagenesis studies, three serines (S87, S114, and S277) were found to be critical for PKA and SRC-2 induction of ERRalpha transcriptional activity. Collectively, these findings indicate that cAMP/PKA signaling enhances ERRalpha phosphorylation and nuclear localization, recruitment to the SP-A promoter, and interaction with PKAcat and SRC-2, resulting in the up-regulation of SP-A gene transcription.
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Affiliation(s)
- Dongyuan Liu
- Department of Biochemistry, The University of Texas Southwestern Medical Center at Dallas, 75390-9038, USA
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Liu D, Yi M, Smith M, Mendelson CR. TTF-1 response element is critical for temporal and spatial regulation and necessary for hormonal regulation of human surfactant protein-A2 promoter activity. Am J Physiol Lung Cell Mol Physiol 2008; 295:L264-71. [PMID: 18487360 PMCID: PMC2519840 DOI: 10.1152/ajplung.00069.2008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Accepted: 05/14/2008] [Indexed: 01/14/2023] Open
Abstract
Expression of the human surfactant protein-A2 (hSP-A2) gene is lung specific, occurs in type II and Clara cells, and is developmentally and hormonally regulated in fetal lung. Using transfected human fetal type II cells, we previously observed that approximately 300 bp of 5'-flanking DNA mediated cAMP and interleukin-1 (IL-1) stimulation and dexamethasone (Dex) inhibition of hSP-A2 promoter activity. This region contains response elements for estrogen-related receptor alpha element (ERRE, -241 bp), thyroid transcription factor (TTF)-1/Nkx2.1 (TTF-binding protein, -171 bp), upstream stimulatory factor 1/2 (E-box, -80 bp), and stimulatory protein (Sp) 1 (G/T-box, -62 bp), which are essential for basal and cAMP induction of hSP-A2 expression. To define genomic regions necessary for developmental, hormonal, and tissue-specific regulation of hSP-A2 expression in vivo, we analyzed transgenic mice carrying hGH reporter genes comprised of 313 bp of hSP-A2 gene 5'-flanking DNA +/- mutation in the TBE or 175 bp of 5'-flanking DNA, containing TBE, E-box and G/T-box, but lacking ERRE. Transgenes containing 313 or 175 bp of hSP-A2 5'-flanking DNA were expressed in a lung cell-specific manner and developmentally regulated in concert with the endogenous mouse SP-A gene. In cultured lung explants from hSP-A(-313):hGH transgenic fetal mice, cAMP and IL-1 induced and Dex inhibited transgene expression. However, the 175-bp hSP-A2 genomic region was insufficient to mediate hormonal regulation of hSP-A2 promoter activity. The finding that expression of the hSP-A(-313TBEmut):hGH transgene was essentially undetectable in fetal lung and was not hormonally regulated in transgenic fetal lung explants underscores the critical importance of the TBE in lung cell-specific, developmental, and hormonal regulation of hSP-A2 gene expression.
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Affiliation(s)
- Dongyuan Liu
- Department of Biochemistry, North Texas March of Dimes Birth Defects Center, The University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Boulevard, Dallas, Texas 75235-9038, USA
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Kolla V, Gonzales LW, Gonzales J, Wang P, Angampalli S, Feinstein SI, Ballard PL. Thyroid transcription factor in differentiating type II cells: regulation, isoforms, and target genes. Am J Respir Cell Mol Biol 2007; 36:213-25. [PMID: 16960125 PMCID: PMC1899316 DOI: 10.1165/rcmb.2006-0207oc] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2006] [Accepted: 08/18/2006] [Indexed: 11/24/2022] Open
Abstract
Thyroid transcription factor-1 (TTF-1, product of the Nkx2.1 gene) is essential for branching morphogenesis of the lung and enhances expression of surfactant proteins by alveolar type II cells. We investigated expression of two TTF-1 mRNA transcripts, generated by alternative start sites and coding for 42- and 46-kD protein isoforms in the mouse, during hormone-induced differentiation of human fetal lung type II cells in culture. Transcript for 42-kD TTF-1 was 20-fold more abundant than TTF-1(46) mRNA by RT-PCR. Only 42-kD protein was detected in lung cells, and its content increased during in vivo development and in response to in vitro glucocorticoid plus cAMP treatment. To examine TTF-1 target proteins, recombinant, phosphorylated TTF-1(42) was expressed in nuclei of cells by adenovirus transduction. By microarray analysis, 14 genes were comparably induced by recombinant TTF-1 (rTTF-1) and hormone treatment, and 9 additional hormone-responsive genes, including surfactant proteins-A/B/C, were partially induced by rTTF-1. The most highly (approximately 10-fold) TTF-1-induced genes were DC-LAMP (LAMP3) and CEACAM6 with induction confirmed by Western analysis and immunostaining. Treatment of cells with hormones plus small inhibitory RNA directed toward TTF-1 reduced TTF-1 content by approximately 50% and inhibited hormone induction of the 23 genes induced by rTTF-1. In addition, knockdown of TTF-1 inhibited 72 of 274 other genes induced by hormones. We conclude that 42-kD TTF-1 is required for induction of a subset of regulated genes during type II cell differentiation.
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Affiliation(s)
- Venkatadri Kolla
- Department of Pediatrics, Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, USA
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Grubor B, Meyerholz DK, Ackermann MR. Collectins and cationic antimicrobial peptides of the respiratory epithelia. Vet Pathol 2006; 43:595-612. [PMID: 16966437 PMCID: PMC2786072 DOI: 10.1354/vp.43-5-595] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The respiratory epithelium is a primary site for the deposition of microorganisms that are acquired during inspiration. The innate immune system of the respiratory tract eliminates many of these potentially harmful agents preventing their colonization. Collectins and cationic antimicrobial peptides are antimicrobial components of the pulmonary innate immune system produced by respiratory epithelia, which have integral roles in host defense and inflammation in the lung. Synthesis and secretion of these molecules are regulated by the developmental stage, hormones, as well as many growth and immunoregulatory factors. The purpose of this review is to discuss antimicrobial innate immune elements within the respiratory tract of healthy and pneumonic lung with emphasis on hydrophilic surfactant proteins and beta-defensins.
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Affiliation(s)
- B Grubor
- Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, IA, USA.
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Islam KN, Mendelson CR. Permissive effects of oxygen on cyclic AMP and interleukin-1 stimulation of surfactant protein A gene expression are mediated by epigenetic mechanisms. Mol Cell Biol 2006; 26:2901-12. [PMID: 16581766 PMCID: PMC1446958 DOI: 10.1128/mcb.26.8.2901-2912.2006] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2005] [Revised: 06/17/2005] [Accepted: 01/17/2006] [Indexed: 11/20/2022] Open
Abstract
Surfactant protein A (SP-A) is important for immune defense within the alveolus. Cyclic AMP (cAMP) stimulation of SP-A expression in lung type II cells is O(2) dependent and mediated by increased phosphorylation and binding of thyroid transcription factor 1 (TTF-1) to an upstream response element (TTF-1-binding element [TBE]). Interleukin-1 (IL-1) stimulation of SP-A expression is mediated by NF-kappaB (p65/p50) activation and increased binding to the TBE. In this study, we found that O(2) also was permissive for IL-1 induction of SP-A expression and for cAMP and IL-1 stimulation of type II cell nuclear protein binding to the TBE. Using chromatin immunoprecipitation, we observed that when type II cells were cultured in 20% O(2), cAMP and IL-1 stimulated the recruitment of TTF-1, p65, CBP, and steroid receptor coactivator 1 to the TBE region of the SP-A promoter and increased local acetylation of histone H3; these effects were prevented by hypoxia. Hypoxia markedly reduced global levels of CBP and acetylated histone H3 and increased the expression of histone deacetylases. Furthermore, hypoxia caused a global increase in histone H3 dimethylated on Lys9 and increased the association of dimethyl histone H3 with the SP-A promoter. These results, together with findings that the histone deacetylase inhibitor trichostatin A and the methyltransferase inhibitor 5'-deoxy(5'-methylthio)adenosine markedly enhanced SP-A expression in lung type II cells, suggest that increased O(2) availability to type II cells late in gestation causes epigenetic changes that permit access of TTF-1 and NF-kappaB to the SP-A promoter. The binding of these transcription factors facilitates the recruitment of coactivators, resulting in the further opening of the chromatin structure and activation of SP-A transcription.
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Affiliation(s)
- Kazi Nazrul Islam
- Department of Biochemistry, The University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Boulevard, Dallas, TX 75390-9038, USA
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Yang MCW, Weissler JC, Terada LS, Deng F, Yang YS. Pleiomorphic adenoma gene-like-2, a zinc finger protein, transactivates the surfactant protein-C promoter. Am J Respir Cell Mol Biol 2004; 32:35-43. [PMID: 15361364 DOI: 10.1165/rcmb.2003-0422oc] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Expression of surfactant protein (SP)-C occurs principally in type II pneumocytes located in the distal lung alveolae. SP-C expression is thought to be primarily regulated by thyroid transcription factor (TTF)-1 and its associated proteins interacting with a previously defined promoter region between -197 and -158 in mice. We screened a human lung cDNA library using a modified yeast one-hybrid system and identified pleiomorphic adenoma gene-like (PLAGL)-2, a ubiquitously expressed zinc finger protein, as a transfactor of the SP-C promoter. The PLAGL2 DNA-binding site was located in the SP-C promoter proximal region close to the TTF-1 sites. This site was demonstrated to be functional by use of electrophoresis mobility shift assay, mutagenesis analysis, and transfection studies. PLAGL2 bound to DNA via its N-terminus zinc fingers and activated the SP-C promoter in a TTF-1-independent manner. Both human and mouse SP-C promoters, but not the SP-B promoter, could be activated by PLAGL2 in transfected human embryonic kidney-293 (HEK293) cells as well as in murine type II (MLE12) cells. The expression of PLAGL2 in isolated human embryonic lung type II cells and its transactivation activity on the SP-C promoter suggest that PLAGL2 may modulate SP-C expression during lung development.
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Affiliation(s)
- Meng-Chun W Yang
- Department of Internal Medicine, Pulmonary and Critical Care Medicine, The University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390-9034, USA
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Fukazawa T, Maeda Y, Sladek FM, Owen-Schaub LB. Development of a cancer-targeted tissue-specific promoter system. Cancer Res 2004; 64:363-9. [PMID: 14729646 DOI: 10.1158/0008-5472.can-03-2507] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Present cancer gene therapy using proapoptotic genes has had limited success because the therapy is prone to cause side effects as a result of the lack of tissue and cancer specificity. To target cancer cells without damaging normal cells, we have designed a novel dual promoter system in which a tissue-specific transcription system under the control of a cancer-specific promoter drives expression of a therapeutic gene. The applicability of this system was demonstrated by adapting it to target lung cancer. We termed this lung cancer system TTS (TTF1 gene under the control of human telomerase reverse transcriptase promoter and human surfactant protein A1 promoter). The TTS system showed much higher promoter activity in lung cancer cells compared with other kinds of cancer and normal lung cells, including stem cells. Moreover, insertion of negative glucocorticoid responsive elements in the system allows it to be drug controllable. The approaches that we have used could be adapted to target other types of cancer. We report a novel cancer-targeted tissue-specific dual promoter system designed for gene therapy.
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Affiliation(s)
- Takuya Fukazawa
- Department of Biomedical Sciences, University of California, Riverside, California, USA.
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Alcorn JL, Islam KN, Young PP, Mendelson CR. Glucocorticoid inhibition of SP-A gene expression in lung type II cells is mediated via the TTF-1-binding element. Am J Physiol Lung Cell Mol Physiol 2003; 286:L767-76. [PMID: 14633512 DOI: 10.1152/ajplung.00280.2003] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Induction of surfactant protein-A (SP-A) gene expression in fetal lung type II cells by cAMP and IL-1 is mediated by increased binding of thyroid transcription factor-1 (TTF-1) and NF-B proteins p50 and p65 to the TTF-1-binding element (TBE) at -183 bp. In type II cell transfections, dexamethasone (Dex) markedly inhibits cAMP-induced expression of rabbit SP-A:human growth hormone (hGH) fusion genes containing as little as 300 bp of the SP-A 5'-flanking sequence. Dex inhibition is blocked by RU-486, suggesting a role of the glucocorticoid receptor (GR). The present study was undertaken to define the mechanisms for GR inhibition of SP-A expression. Cotransfection of primary cultures of type II cells with a GR expression vector abrogated cAMP induction of SP-A promoter activity while, at the same time, causing a 60-fold induction of cotransfected mouse mammary tumor virus (MMTV) promoter. In lung cells transfected with a fusion gene containing three TBEs fused to the basal SP-A promoter, Dex prevented the stimulatory effect of IL-1 on TTF-1 induction of SP-A promoter activity, suggesting that the GR inhibits SP-A promoter activity through the TBE. In gel shift assays using nuclear extracts from human fetal type II cells cultured in the absence or presence of cAMP, Dex markedly reduced binding of nuclear proteins to the TBE and blocked the stimulatory effect of cAMP on TBE-binding activity. Our finding that Dex increased expression of the NF-kappaB inhibitory partner IkappaB-alpha suggests that the decrease in TBE-binding activity may be caused, in part, by GR inhibition of NF-kappaB interaction with this site.
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Affiliation(s)
- Joseph L Alcorn
- Dept. of Biochemistry, Univ. of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9038, USA
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DeMartini JC, Bishop JV, Allen TE, Jassim FA, Sharp JM, de las Heras M, Voelker DR, Carlson JO. Jaagsiekte sheep retrovirus proviral clone JSRV(JS7), derived from the JS7 lung tumor cell line, induces ovine pulmonary carcinoma and is integrated into the surfactant protein A gene. J Virol 2001; 75:4239-46. [PMID: 11287573 PMCID: PMC114169 DOI: 10.1128/jvi.75.9.4239-4246.2001] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ovine pulmonary carcinoma (OPC) is a contagious neoplasm of alveolar epithelial type II (ATII) or Clara cells caused by a type D/B chimeric retrovirus, jaagsiekte sheep retrovirus (JSRV). Here we report the isolation, sequencing, pathogenicity, and integration site of a JSRV provirus isolated from a sheep lung tumor cell line (JS7). The sequence of the virus was 93 to 99% identical to other JSRV isolates and contained all of the expected open reading frames. To produce virions and test its infectivity, the JS7 provirus (JSRV(JS7)) was cloned into a plasmid containing a cytomegalovirus promoter and transfected into 293T cells. After intratracheal inoculation with virions from concentrated supernatant fluid, JSRV-associated OPC lesions were found in one of four lambs, confirming that JSRV(JS7) is pathogenic. In JS7-cell DNA, the viral genome was inserted in the protein-coding region for the surfactant protein A (SP-A) gene, which is highly expressed in ATII cells, in an orientation opposite to the direction of transcription of the SP-A gene. No significant transcription was detected from either the viral or the SP-A gene promoter in the JS7 cell line at passage level 170. The oncogenic significance of the JSRV proviral insertion involving the SP-A locus in the JS7 tumor cell line is unknown.
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Affiliation(s)
- J C DeMartini
- Department of Pathology, Colorado State University, Fort Collins 80524, USA.
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Mendelson CR. Role of transcription factors in fetal lung development and surfactant protein gene expression. Annu Rev Physiol 2000; 62:875-915. [PMID: 10845115 DOI: 10.1146/annurev.physiol.62.1.875] [Citation(s) in RCA: 156] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Branching morphogenesis of the lung and differentiation of specialized cell populations is dependent upon reciprocal interactions between epithelial cells derived from endoderm of embryonic foregut and surrounding mesenchymal cells. These interactions are mediated by elaboration and concerted actions of a variety of growth and differentiation factors binding to specific receptors. Such factors include members of the fibroblast growth factor family, sonic hedgehog, members of the transforming growth factor-beta family, epidermal growth factor, and members of the platelet-derived growth factor family. Hormones that increase cyclic AMP formation, glucocorticoids, and retinoids also play important roles in branching morphogenesis, alveolar development, and cellular differentiation. Expression of the genes encoding these morphogens and their receptors is controlled by a variety of transcription factors that also are highly regulated. Several of these transcription factors serve dual roles as regulators of genes involved in early lung development and in specialized functions of differentiated cells. Targeted null mutations of genes encoding many of these morphogens and transcription factors have provided important insight into their function during lung development. In this chapter, the cellular and molecular mechanisms that control lung development are considered, as well as those that regulate expression of the genes encoding the surfactant proteins.
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Affiliation(s)
- C R Mendelson
- Department of Biochemistry, University of Texas Southwestern Medical Center at Dallas 75235-9038, USA.
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Mendelson CR, Gao E, Li J, Young PP, Michael LF, Alcorn JL. Regulation of expression of surfactant protein-A. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1408:132-49. [PMID: 9813283 DOI: 10.1016/s0925-4439(98)00063-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- C R Mendelson
- Departments of Biochemistry and Obstetrics-Gynecology, The Cecil H. and Ida Green Center for Reproductive Biology Sciences, The University of Texas Southwestern Medical Center at Dallas, TX 75235-9038, USA
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