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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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2
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Tremblay Y, Morin-Labbé A. Neonatal Lung Diseases: A Clinical Potential for Sex Steroids and a Novel Intracrine Organ. Front Med (Lausanne) 2021; 8:664969. [PMID: 34026792 PMCID: PMC8131950 DOI: 10.3389/fmed.2021.664969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Accepted: 04/06/2021] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yves Tremblay
- Reproduction Axis, Perinatal and Child Health, CRCHU de Québec, Québec, QC, Canada.,Department of Obstetric, Gynecology & Reproduction, Faculty of Medicine, Laval University, Québec, QC, Canada.,Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Laval University, Québec, QC, Canada
| | - Alexia Morin-Labbé
- Reproduction Axis, Perinatal and Child Health, CRCHU de Québec, Québec, QC, Canada
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Chen J, Mishra R, Yu Y, McDonald JG, Eckert KM, Gao L, Mendelson CR. Decreased 11β-hydroxysteroid dehydrogenase 1 in lungs of steroid receptor coactivator (Src)-1/-2 double-deficient fetal mice is caused by impaired glucocorticoid and cytokine signaling. FASEB J 2020; 34:16243-16261. [PMID: 33070362 DOI: 10.1096/fj.202001809r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/11/2020] [Accepted: 09/29/2020] [Indexed: 01/30/2023]
Abstract
Our previous research revealed that steroid receptor coactivators (Src)-1 and -2 serve a critical cooperative role in production of parturition signals, surfactant protein A and platelet-activating factor, by the developing mouse fetal lung (MFL). To identify the global landscape of genes in MFL affected by Src-1/-2 double-deficiency, we conducted RNA-seq analysis of lungs from 18.5 days post-coitum (dpc) Src-1-/- /-2-/- (dKO) vs. WT fetuses. One of the genes most highly downregulated (~4.8 fold) in Src-1/-2 dKO fetal lungs encodes 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), which catalyzes conversion of inactive 11-dehydrocorticosterone to the glucocorticoid receptor (GR) ligand, corticosterone. Glucocorticoids were reported to upregulate 11β-HSD1 expression in various cell types via induction of C/EBP transcription factors. We observed that C/ebpα and C/ebpβ mRNA and protein were markedly reduced in Src-1/-2 double-deficient (Src-1/-2d/d ) fetal lungs, compared to WT. Moreover, glucocorticoid induction of 11β-hsd1, C/ebpα and C/ebpβ in cultured MFL epithelial cells was prevented by the SRC family inhibitor, SI-2. Cytokines also contribute to the induction of 11β-HSD1. Expression of IL-1β and TNFα, which dramatically increased toward term in lungs of WT fetuses, was markedly reduced in Src-1/-2d/d fetal lungs. Our collective findings suggest that impaired lung development and surfactant synthesis in Src-1/-2d/d fetuses are likely caused, in part, by decreased GR and cytokine induction of C/EBP and NF-κB transcription factors. This results in reduced 11β-HSD1 expression and glucocorticoid signaling within the fetal lung, causing a break in the glucocorticoid-induced positive feedforward loop.
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Affiliation(s)
- Jingfei Chen
- Department of Obstetrics and Gynecology, Xiangya Hospital of Central South University, Changsha, China.,Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ritu Mishra
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yaqin Yu
- Department of Physiology, Second Military Medical University, Shanghai, P.R. China
| | - Jeffrey G McDonald
- Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Kaitlyn M Eckert
- Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lu Gao
- Department of Physiology, Second Military Medical University, Shanghai, P.R. China.,School of Medicine, The International Peace Maternity and Child Health Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Carole R Mendelson
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX, USA
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Developmental Decline in the MicroRNA 199a (miR-199a)/miR-214 Cluster in Human Fetal Lung Promotes Type II Cell Differentiation by Upregulating Key Transcription Factors. Mol Cell Biol 2018; 38:MCB.00037-18. [PMID: 29507184 DOI: 10.1128/mcb.00037-18] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Accepted: 02/27/2018] [Indexed: 02/07/2023] Open
Abstract
The major surfactant protein, SP-A (a product of the SFTPA gene), serves as a marker of type II pneumocyte differentiation and surfactant synthesis. SFTPA expression in cultured human fetal lung (HFL) epithelial cells is upregulated by hormones that increase cyclic AMP (cAMP) and activate TTF-1/NKX2.1 and NF-κB. To further define mechanisms for type II cell differentiation and induction of SP-A, we investigated roles of microRNAs (miRNAs). Using microarray to identify differentially expressed miRNAs in HFL epithelial cells during type II cell differentiation in culture, we observed that members of the miRNA 199a (miR-199a)/miR-214 cluster were significantly downregulated during differentiation. Validated and predicted targets of miR-199a-3p/miR-199a-5p and miR-214, which serve roles in type II cell differentiation (COX-2, NF-κB p50/p65, and CREB1), and the CREB1 target, C/EBPβ, were coordinately upregulated. Accordingly, overexpression of miR-199a-5p, miR-199a-3p, or miR-214 mimics in cultured HFL epithelial cells decreased COX-2, NF-κB p50/p65, CREB1, and C/EBPβ proteins, with an associated inhibition of SP-A expression. Interestingly, overexpression of the EMT factor, ZEB1, which declines during cAMP-induced type II cell differentiation, increased pri-miR-199a and reduced the expression of the targets NF-κB/p50 and COX-2. Collectively, these findings suggest that the developmental decline in miR-199a/miR-214 in HFL causes increased expression of critical targets that enhance type II cell differentiation and SP-A expression.
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Mendelson CR, Montalbano AP, Gao L. Fetal-to-maternal signaling in the timing of birth. J Steroid Biochem Mol Biol 2017; 170:19-27. [PMID: 27629593 PMCID: PMC5346347 DOI: 10.1016/j.jsbmb.2016.09.006] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 07/05/2016] [Accepted: 09/10/2016] [Indexed: 12/13/2022]
Abstract
Preterm birth remains the major cause of neonatal morbidity and mortality throughout the world. This is due, in part, to our incomplete understanding of the mechanisms that underlie the maintenance of pregnancy and the initiation of parturition at term. In this article, we review our current knowledge of the complex, interrelated and concerted mechanisms whereby progesterone maintains myometrial quiescence throughout most of pregnancy, as well as those that mediate the upregulation of the inflammatory response and decline in progesterone receptor function leading to parturition. Herein, we review findings that demonstrate a role of the fetus in the timing of birth. Specifically, we focus on our own studies indicating that maturation of the fetal lung and enhanced secretion of the surfactant components, surfactant protein A (SP-A) and the potent inflammatory glycerophospholipid, platelet-activating factor (PAF), initiate a signaling cascade culminating in parturition. Our studies suggest an essential role of steroid receptor coactivators, SRC-1 and SRC-2, which activate expression of genes encoding SP-A and LPCAT1. LPCAT1 is a key enzyme in the synthesis of PAF, as well as DPPC, a highly surface-active glycerophospholipid component of surfactant. Thus, we describe a novel pathway through which the fetus contributes to the initiation of labor by signaling the mother when its lungs have achieved sufficient maturity for survival in an aerobic environment.
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Affiliation(s)
- Carole R Mendelson
- Departments of Biochemistry, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, USA; Obstetrics & Gynecology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, USA.
| | - Alina P Montalbano
- Departments of Biochemistry, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, USA
| | - Lu Gao
- Departments of Biochemistry, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, USA
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Silveyra P, Floros J. Genetic complexity of the human surfactant-associated proteins SP-A1 and SP-A2. Gene 2012; 531:126-32. [PMID: 23069847 DOI: 10.1016/j.gene.2012.09.111] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 09/08/2012] [Accepted: 09/29/2012] [Indexed: 01/08/2023]
Abstract
Pulmonary surfactant protein A (SP-A) plays a key role in innate lung host defense, in surfactant-related functions, and in parturition. In the course of evolution, the genetic complexity of SP-A has increased, particularly in the regulatory regions (i.e. promoter, untranslated regions). Although most species have a single SP-A gene, two genes encode SP-A in humans and primates (SFTPA1 and SFTPA2). This may account for the multiple functions attributed to human SP-A, as well as the regulatory complexity of its expression by a relatively diverse set of protein and non-protein cellular factors. The interplay between enhancer cis-acting DNA sequences and trans-acting proteins that recognize these DNA elements is essential for gene regulation, primarily at the transcription initiation level. Furthermore, regulation at the mRNA level is essential to ensure proper physiological levels of SP-A under different conditions. To date, numerous studies have shown significant complexity of the regulation of SP-A expression at different levels, including transcription, splicing, mRNA decay, and translation. A number of trans-acting factors have also been described to play a role in the control of SP-A expression. The aim of this report is to describe the genetic complexity of the SFTPA1 and SFTPA2 genes, as well as to review regulatory mechanisms that control SP-A expression in humans and other animal species.
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Affiliation(s)
- Patricia Silveyra
- Center for Host Defense, Inflammation, and Lung Disease (CHILD) Research, Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA, 17033, USA
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Epigenetic regulation of surfactant protein A gene (SP-A) expression in fetal lung reveals a critical role for Suv39h methyltransferases during development and hypoxia. Mol Cell Biol 2011; 31:1949-58. [PMID: 21402781 DOI: 10.1128/mcb.01063-10] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
SP-A gene expression is developmentally regulated in fetal lung. Cyclic AMP (cAMP) induction of SP-A expression in human fetal lung type II cells is O(2) dependent and is mediated by increased binding of TTF-1/Nkx2.1 and NF-κB to a critical response element (TBE). This is associated with increased acetylation and decreased methylation of H3K9 at the TBE. Using chromatin immunoprecipitation analysis of fetal lung between 15.5 and 19.0 days of gestation, we observed that the developmental induction of SP-A was associated with increased recruitment of TTF-1, NF-κB, PCAF, and CBP, as well as enhanced acetylation and decreased methylation of histone H3K9 at the TBE. Importantly, expression and TBE binding of the H3K9 methyltransferases, Suv39h1 and Suv39h2, was inversely correlated with the developmental upregulation of SP-A. In human fetal lung epithelial cells, Suv39H1 and Suv39H2 mRNA levels declined with cAMP induction of SP-A. Moreover, hypoxia, which inhibits cAMP stimulation of SP-A, markedly increased Suv39h1 and Suv39h2 binding to the TBE. Finally, short hairpin RNA knockdown of Suv39H1 or Suv39H2 in fetal lung epithelial cells repressed H3K9 methylation and greatly enhanced SP-A expression. Collectively, our findings suggest that Suv39H1 and Suv39H2 are key hypoxia-induced methyltransferases; their decline in fetal lung during late gestation is critical for epigenetic changes resulting in the developmental induction of SP-A.
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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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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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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: 142] [Impact Index Per Article: 5.9] [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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