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(Hypertension. 1995;25:704-710.)
© 1995 American Heart Association, Inc.
Articles |
Endogenous Human Renin Expression and Promoter Activity in CALU-6, a Pulmonary Carcinoma Cell Line
From the Departments of Medicine, Anatomy, and Physiology and Biophysics, University of Iowa College of Medicine, Iowa City.
Correspondence to Curt D. Sigmund, PhD, Assistant Professor and Director, Transgenic Animal Facility, Departments of Medicine and Physiology and Biophysics, University of Iowa, 6-432 Bowen Science Bldg, Iowa City, IA 52242.
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Abstract |
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Abstract We have previously reported that transgenic mice containing the human renin gene express high levels of human renin mRNA in the lung. We show in this report that human renin expression in two lines of transgenic mice is developmentally regulated. Human renin expression is not evident in the transgenic mouse lung at 15.5 days of gestation, is detectable at 17.5 days of gestation, peaks around birth, and remains elevated into adulthood. In situ hybridization of mouse fetal lung samples at 18.5 days of gestation revealed that human renin was exclusively expressed in pulmonary type II epithelial cells. A survey of the medical literature revealed a number of clinical cases in which hypertension was caused by renin-secreting pulmonary tumors and a fairly widespread occurrence of immunoreactive renin in banked pulmonary tumors of diverse origin. This prompted us to examine a number of pulmonary tumor cell lines to determine whether they express human renin mRNA. One pulmonary carcinoma cell line, CALU-6, expressed human renin mRNA endogenously. Human renin expression in these cells was induced approximately 100-fold after treatment with forskolin, 8-bromoadenosine 3':5'-cyclic monophosphate, or N6,2'-O-dibutyryladenosine 3':5'-cyclic monophosphate. Transfection analysis of human renin promoter–luciferase fusion constructs revealed the presence of cell-specific positive and negative regulatory elements in the human renin 5'-flanking DNA. This cell line is the only immortalized human cell line that expresses high levels of endogenous human renin mRNA and should provide an excellent tool for studying the regulation of human renin expression in vitro.
Key Words: mice, transgenic • transfection • lung • hypertension, genetic • in situ hybridization
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Introduction |
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The human renin (HuRen) gene is expressed in an embryologically diverse set of tissues. Although kidney is the primary site of renin synthesis, storage, and release, a number of extrarenal tissues synthesize renin as a component of tissue renin-angiotensin systems that may serve local functions.1 2 During the past few years, a great deal of effort has been directed at understanding the molecular mechanisms regulating renin gene expression in renal and extrarenal tissues. Although many of these studies were initially performed using the mouse and rat renin genes, studies using transgenic animals to examine the expression and regulation of the human renin gene have recently been reported.3 4 5 In these studies, transgenic mice were used to overexpress human renin with the aim of developing novel models with which to study the contribution of the renin-angiotensin system to the pathogenesis of essential hypertension. Although these studies have been informative in terms of a basic understanding of human renin gene expression, the exclusive use of transgenic mice to elucidate the molecular mechanisms that control renin expression is unlikely to be successful because the approach is expensive and time- and labor-intensive.
Clearly, one of the major limitations that has hampered the analysis of renin genes from all species has been the lack of suitable cell lines for these studies. Although there are numerous articles describing the identification of regulatory elements controlling the renin gene, the conclusions reached have often been based on results from non–renin-expressing cell lines.6 Because these cell lines do not normally express renin mRNA, the results obtained must be interpreted cautiously. A renin-expressing immortalized cell line derived from the mouse kidney, As4.1, has been developed and is being used extensively to map the regulatory elements controlling expression of the mouse renin genes.7 However, it remains unclear whether a cell line derived from one species can be used effectively to probe the regulation of a renin gene from another species. Therefore, the As4.1 cell line may not provide an appropriate tool for examining the human renin gene. Although human choriodecidua cells retain the ability to secrete renin for several passages in culture, the fact that the level of renin mRNA in them is quite low and the necessity to constantly purify chorionic cells for primary cultures make them a less convenient model than an immortalized cell line.8 9 Therefore, the purpose of the current study was to take advantage of three observations to identify an immortalized human renin–expressing cell line derived from the lung: (1) human renin mRNA is highly expressed in the lung of four independent lines of transgenic mice,3 (2) renin and renin mRNA have been localized in human pulmonary tumors of diverse origin,10 11 12 and (3) human renin is present in human fetal lung.13
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Methods |
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Animals
Transgenic mice containing the human renin gene have been described previously.3 14 All transgenic mice were maintained by successive backcross breeding to C57BL/6J (Jackson Laboratory). Adult kidney and lung tissues were obtained from female HuRen transgenic mice at the time the animals were killed. All tissues were snap-frozen in liquid nitrogen and stored frozen at -70°C. All mice were fed standard mouse chow and water ad libitum. Timed pregnancies were set up by breeding four female HuRen transgenic mice to four male HuRen transgenic mice. Female mice were visually inspected for a vaginal copulation plug and the date of the plug was recorded. The detection of a vaginal plug corresponded to 0.5 days of gestation. One pregnant mouse from each of transgenic lines 9 and 10 was killed at 15.5, 17.5, and 18.5 days of gestation, and the last was allowed to give birth. Newborn pups were killed at approximately 12 hours of age. The identity of transgenic and nontransgenic fetuses was determined by polymerase chain reaction of DNA isolated from placenta or tail DNA, as previously described.14 Fetuses and newborns were dissected under phosphate-buffered saline (PBS) with the use of a Nikon SMZ-2T dissecting microscope. Care of the mice used in these experiments met or exceeded the guidelines for the care and use of experimental animals set forth by the National Institutes of Health. Procedures used were approved by the University Animal Care and Use Committee at the University of Iowa.
Cell Culture
Cell lines NCI-H358, NCI-H520, NCI-H522, NCI-H596, NCI-H1264,
NCI-H1299, NCI-H1466, 3T3, and THP-1 were grown in RPMI 1640 medium
containing 10% fetal bovine serum (FBS). Cell lines A-427, A-549,
CALU-3, CALU-6, SK-LU, and SK-MES were grown in Dulbecco's modified
Eagle medium supplemented with sodium pyruvate, nonessential amino
acids, and 10% FBS. Cell line A-431 was grown in Dulbecco's
high-glucose medium containing 10% FBS. Cell line CALU-1 was grown in
McCoy's 5A medium containing 10% FBS. All cell lines were grown at
37°C in 95% air/5% CO2 to 90% confluence. To stimulate
increased intracellular cyclic adenosine monophosphate (cAMP), CALU-6
cells were treated with forskolin (1 µmol/L, 10 µmol/L, or 100
µmol/L as indicated; Sigma Chemical Co), 10 mmol/L 8-bromoadenosine
3':5'-cyclic monophosphate (8-Br-cAMP; Sigma), or 10 mmol/L
N6,2'-O-dibutyryladenosine
3':5'-cyclic monophosphate (Bt2-cAMP; Sigma) for 24 hours.
Dimethyl sulfoxide served as the vehicle control.
Expression Studies
Total tissue RNAs were isolated by homogenization in guanidine
isothiocyanate followed by phenol emulsion extraction at pH 4.0 by use
of a modification of a method previously described.15 16
RNA isolation from cell cultures was performed essentially as for whole
tissues, with the following modifications. Cells were washed twice with
PBS and then were scraped from confluent T75 flasks into 5 mL PBS.
Cells were pelleted by centrifugation and frozen as cell pellets at
-70°C until needed. Cell pellets were resuspended in guanidine
isothiocyanate mix and incubated on ice for 15 to 30 minutes. Cellular
homogenates were phenol-extracted and ethanol-precipitated as
above.
Northern blotting and hybridization were done as previously described.17 The HuRen probe was a single-stranded antisense RNA made from a partial HuRen complementary DNA (cDNA) cloned in pGEM-3.3 To ensure the specific detection of HuRen transcripts, Northern blots were treated with 1.0 µg/mL ribonuclease A (RNase A, Sigma) in 2x standard saline citrate for 15 minutes at room temperature. We have previously demonstrated that this procedure removes nonspecific hybridization of single-stranded RNA probes.3
For in situ hybridizations, frozen sections of mouse fetal lung at 18.5 days of gestation or adult kidney were cut 8 µm thick on a Reichert-Jung cryostat and were hybridized to the same antisense HuRen SP6 RNA probe described above. The SP6 transcript was labeled with [3H]UTP and used as previously described.18 19 The specificity of the hybridization was tested with a sense orientation probe on transgenic lung and kidney tissue. Sections were stained with hematoxylin and eosin.
Transfection Analysis
Fusions between the HuRen promoter and the luciferase reporter
gene were made by use of the pGL-2 reporter system and the pGL-2Basic
and pGL-2Enhancer plasmid vectors, following standard cloning
techniques. All constructs have a common 3' end at +13 relative to the
start site of HuRen transcription, and have promoters of varying length
ending at coordinates -149 (Kpn I), -453 (Xba
I), -896 (HindIII), -1301 (Xba I), -2595
(BstYI), and -2750 (EcoRI). Plasmid DNAs were
purified on cesium chloride density gradients and ethanol-precipitated
twice before transfection. The concentration of the plasmid DNA was
determined by absorbance at 260 nm and was confirmed by gel
electrophoresis and ethidium bromide staining. CALU-6 cells were
transfected by use of the lipofectin reagent (Gibco-BRL), following the
procedure recommended by the manufacturer, and Ltk- cells
were transfected using the DEAE-dextran method, as previously
described.20 For the CALU-6 transfections, equimolar
amounts of luciferase reporter plasmid (starting at 4 µg for the
-149 construct) were cotransfected with 0.5 µg of an SV40
promoter–ß-galactosidase control. Ten micrograms of plasmid DNA was
transfected into Ltk- cells. Luciferase activity assays
were performed with a commercially available kit (Promega), following
the directions recommended by the manufacturer, and were read in a
Monolight 2010 automatic luminometer. ß-Galactosidase activity was
measured using the Galacto-light kit, following the directions
recommended by the manufacturer (Tropix). ß-Galactosidase activity
was used to correct for transfection efficiency, sample loss, and other
factors that could affect results. Experiments in which
ß-galactosidase activity varied more than twofold were discarded.
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Results |
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Expression of Human Renin in the Transgenic Mouse Lung
The temporal pattern of renin expression in the mouse and rat kidney is well characterized, with expression appearing between 14.5 and 15.5 days of gestation,21 22 and the temporal pattern of HuRen expression in the kidney of transgenic mice has been reported.14 To determine whether a similar HuRen temporal expression profile existed in lung, pregnancies were timed and lung samples from mouse fetuses at 15.5, 17.5, and 18.5 days of gestation and from newborn transgenic and nontransgenic control mice from line 10 were isolated. No HuRen mRNA was evident in the lung at 15.5 days of gestation (Fig 1). Expression became evident at 17.5 days of gestation and increased thereafter, peaking just before birth. High-level expression was then retained throughout neonatal and adult life. The highest level of expression was observed in a lung from an animal that remained in utero several hours after the rest of the litter was delivered (Fig 1A). No expression was observed in the nontransgenic controls. Equivalent loading of the blot was confirmed by staining the ribosomal RNAs with methylene blue (Fig 1B). Identical results were obtained with transgenic line 9 (data not shown).
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HuRen mRNA in the lung of these transgenic mice was reproducibly visualized as multiple transcripts on Northern blots. The main hybridizing band comigrates with mature HuRen mRNA in kidney, and the higher–molecular weight band may reflect the use of upstream start sites or of alternative splice sites. Only mature HuRen mRNA was detected in the kidney from the same transgenic mice (in Fig 1, compare kidney lanes to lung lanes).
The cell specificity of pulmonary HuRen expression was determined by in situ hybridization on fetal lung sections at 18.5 days of gestation. The data in Fig 2 reveal that HuRen expression is highly restricted to cells with the anatomic localization consistent with type II epithelial cells (Fig 2A and 2C). This is the same anatomic localization reported for expression of surfactant-associated protein mRNA in the fetal lung.18 19 No HuRen mRNA was detected in epithelial cells of the alveolar lumens (Fig 2A and 2C) or in blood vessels, and no specific hybridization was detected when a sense orientation probe was used (Fig 2E). The specificity of the hybridization was further tested on kidney sections from an adult transgenic mouse and showed the classical juxtaglomerular cell localization (Fig 2E, inset).
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Expression of HuRen in the CALU-6 Pulmonary Carcinoma Cell Line
Although the lung is not commonly considered a renin-expressing
tissue, evidence from the clinical literature (Table 1)
suggests there may indeed be a small population of renin-expressing
cells in lung. Renin or renin mRNA has been reported to be present
in a number of diverse pulmonary tumor types, including
leiomyosarcoma,10 adenocarcinoma,11 12
squamous cell sarcoma,12 large cell
sarcoma,12 and small cell sarcoma.12 In each
case, renin was immunocytochemically localized to the tumor
vasculature.
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These observations prompted us to examine a series of 16 pulmonary and 3 nonpulmonary tumor cell lines for evidence of HuRen mRNA expression on Northern blot analysis. These cell lines were derived from tumors of diverse origins that were either banked at the University of Iowa Tumor Bank or available from the American Type Culture Collection (Table 2). Fifteen of 16 pulmonary tumor cell lines, including W126 VA4 cells that previously were reported to express renin mRNA,23 and all nonpulmonary tumor cell lines, including human embryonic kidney 293 cells, were devoid of detectable human renin mRNA (Fig 3; not all data shown). On the contrary, easily detectable HuRen mRNA was clearly evident in CALU-6 cells, which are derived from a pulmonary anaplastic carcinoma (Fig 3, lane 11). Importantly, expression of HuRen mRNA was maintained after many serial passages of the CALU-6 cells (data not shown).
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The fact that CALU-6 cells express HuRen endogenously strongly suggests that they contain the correct complement of transcription factors necessary for the expression of the HuRen gene. To test this hypothesis, we used CALU-6 cells and control mouse Ltk- cells as hosts in transient transfection assays utilizing constructs containing various segments of the HuRen promoter fused to the luciferase reporter gene. In general, the HuRen promoter was between 10 and 20 times less potent than the basal SV40 promoter in directing luciferase expression in CALU-6 cells, indicating that the HuRen promoter is inherently weak.24 To compare the efficiency of the various HuRen promoter segments examined, luciferase activity was used as an indicator of transcriptional activity, and in each segment transfection was normalized to the activity of the basal HuRen promoter, which extends from -149 to +13. As shown in Table 3, HuRen promoter activity in CALU-6 cells varied significantly as the amount of 5'-flanking DNA present in the construct was increased. Instead of a progressive increase in promoter activity, as might be expected if the basal promoter were not sufficient to direct transcription, there was first a decrease and then an increase in promoter activity after relatively short additions to the basal promoter sequence. First, a construct extending to -453 exhibited activity fourfold lower than that of the basal promoter. Extending the 5'-flanking DNA to -896 resulted in a fivefold induction in transcriptional activity compared with the -453 construct and returned promoter activity to the baseline level defined by the -149 promoter. The three longer constructs (-1301, -2595, and -2750) all had approximately 50% of the activity of the basal promoter. Taken together, the data suggest the close localization of both positive and negative regulatory elements upstream of the HuRen gene. These elements act in a cell-specific manner, because no modulation of promoter activity was observed in Ltk- cells. The presence of the ubiquitous SV40 enhancer caused a further stimulation of promoter activity, with its greatest effects in CALU-6 cells. The activity of the HuRen promoter in the presence of the SV40 enhancer partially mirrored its activity in the absence of the enhancer, the highest level of expression being evident with the -896 promoter.
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The HuRen gene contains regulatory elements that confer cAMP responsiveness, and cAMP-inducible expression of the human, mouse, and rat renin genes has been reported.9 25 We therefore examined whether HuRen expression in CALU-6 cells was similarly responsive. CALU-6 cells were treated with vehicle alone or with forskolin for 24 hours. Forskolin stimulates adenylyl cyclase by a receptor-independent mechanism and caused a clear and reproducible increase in steady-state HuRen mRNA that was maximal at a concentration of 10-5 mol/L (Fig 4). Quantitative slot blot analysis revealed that the induction was nearly 100-fold (data not shown). A similar induction in HuRen mRNA accumulation was caused by 8-Br-cAMP or Bt2-cAMP treatment, demonstrating that the response was not an artifact of the forskolin treatment (Fig 4). As for HuRen mRNA in transgenic lung, additional high–molecular weight HuRen transcripts were detected in CALU-6 cells. These transcripts clearly encode HuRen mRNA, because they survived extensive treatment of the blots with ribonuclease A.
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Discussion |
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HuRen Expression in the Transgenic Mouse Lung
We previously demonstrated that a HuRen genomic transgene containing all exons and introns and extending 892 bp in the 5' direction and 400 bp in the 3' direction was expressed in a highly tissue-specific and cell-specific manner.3 14 In kidney, HuRen mRNA was restricted to juxtaglomerular cells, and its level was increased after angiotensin-converting enzyme inhibition. In addition, active human renin protein was released into the systemic circulation, and its level was significantly increased after either angiotensin-converting enzyme inhibition or isoproterenol stimulation (M.W. Thompson and C.D. Sigmund, unpublished data, 1994). Taken together, our data suggest that the HuRen gene is appropriately expressed and regulated in this transgenic mouse model.
HuRen mRNA is highly expressed in the lung of adult transgenic mice and exhibits a temporal expression pattern clearly distinct from that of the kidney.14 That this observation was reproducible in at least two independent lines of transgenic mice rules out position effect as an explanation for our observations. Whether lung is a bona fide site of renin synthesis in humans remains unclear, but the possibility is supported by several findings: polymerase chain reaction expression results suggesting that renin is expressed at a low level in the mouse and rat lung26 ; the widespread occurrence of renin-containing cells in pulmonary tumors, some of which were causative for hypertension in the patients who had them10 11 12 ; and expression of renin in human fetal lung.13 It nevertheless remains puzzling that the cellular localization of HuRen mRNA in the transgenic lung is markedly different from that previously reported in human fetal lung and human lung tumors.
The time- and cell-specific expression of human renin in the transgenic mouse lung is reminiscent of the time- and cell-specific expression of certain pulmonary surfactant–associated protein mRNAs.18 19 Therefore, it remains possible that the appropriate cell specificity and regulation of human renin observed in the transgenic mouse kidney3 14 may not extend itself to other tissues such as the lung. Although the 892-bp HuRen promoter used in this transgene may be sufficient for renal expression, it may not properly target HuRen expression to, or restrict HuRen expression from, other tissues. Indeed, HuRen mRNA is also evident in adipose tissue in all lines of transgenic mice examined. Although white and brown adipose tissues are normal sites of angiotensinogen synthesis, they are not recognized as normal sites of renin synthesis.27 28 Nevertheless, it remains important to point out that four independent lines of transgenic mice, each with unique insertion sites and transgene copy number, expressed HuRen mRNA in lung. This observation effectively rules out position artifacts on expression as the cause of pulmonary HuRen expression in transgenic mice.
Expression and Regulation of HuRen in CALU-6 Cells
An analysis of a series of pulmonary tumor cell lines revealed
that a single anaplastic carcinoma cell line, CALU-6, expressed its
endogenous renin gene. Expression of renin in CALU-6 cells was highly
inducible by elevation of the intracellular cAMP concentration.
Although the frequency of renin expression in the pulmonary tumor cell
lines was lower than expected on the basis of the incidence of renin
expression in primary pulmonary tumors (Table 1), it is not surprising
because of the very low frequency of renin expression in cell lines
derived from renal tumors or renal cell lines immortalized with
oncogenes. In most previous cases, renin mRNA and immunoreactive renin
were quickly lost when renin-expressing cells were placed in
culture.29 30 It remains unclear which molecular
mechanisms account for the maintenance of the renin-expressing
phenotype in CALU-6 cells. Also, because cAMP induces HuRen mRNA
100-fold in CALU-6 cells, it may become important to screen the other
pulmonary tumor cell lines under similar conditions. Indeed, W126 VA4
cells have been shown to express HuRen mRNA under cAMP-stimulated
conditions.23
Transient transfection analysis of the HuRen promoter in the CALU-6 cell line has identified a closely linked series of positive and negative regulatory elements in the 5'-flanking DNA that acts in a cell-specific fashion. Although each element appeared to exert relatively weak effects on transcriptional activity (increasing it fourfold to fivefold) independently, it remains possible that such an arrangement of closely linked sites may allow the gene to be tightly regulated in response to both endocrine and physiological cues. The localization of closely linked positive and negative elements has been proposed to exist in the HuRen 5'-flanking region.31 However, the results of that study were particularly difficult to interpret because a cell line that did not express renin endogenously was used. In addition, comparisons were made between constructs that contained a dual promoter, consisting of the basal human renin promoter (-149 to +13) and the thymidine kinase promoter, and constructs that contained only the thymidine kinase promoter. In our experiments, there was no significant modulating effect of the -453 to -149, -896 to -149, or -1301 to -149 region when placed upstream of the basal thymidine kinase promoter in CALU-6 cells (data not shown). Indeed, the thymidine kinase promoter appears to be at least 10 times more active than the HuRen promoter in CALU-6 cells and may therefore mask the effects of relatively weak regulatory elements.
The presence of the SV40 enhancer induced the expression of each construct fivefold to 20-fold in CALU-6 cells, indicating that the HuRen promoter has the capacity to be induced in response to a classic enhancer element. A functional search of the immediate 2750 bp of 5'-flanking DNA has failed to identify any functional regulatory elements that exert large effects on transcriptional activity. Interestingly, a distal region of the 5'-flanking region of the mouse Ren-1c gene has been reported to stimulate expression of the mouse renin promoter 10-fold in a kidney tumor cell line.32 It remains unclear whether such an element will be identified in the human renin 5'-flanking DNA.
In conclusion, the CALU-6 cell line should provide an excellent new tool for (1) studying the expression and regulation of the endogenous human renin gene, (2) providing a host for transfection studies in which HuRen promoter-reporter gene fusions are used, and (3) providing a source of nuclear proteins containing transcription factors active on the HuRen gene. Experiments addressing each of these issues are currently in progress.
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Acknowledgments |
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This work was supported by grant HL-48058 from the National Institutes of Health. Dr Sigmund is an Established Investigator of the American Heart Association. We would like to thank Dr Jeanne Snyder for her assistance in performing the in situ hybridizations and Norma Sinclair and Lucy Robbins for their excellent technical assistance.
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References |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
1. Lindpaintner K, Wilhelm MJ, Jin M, Unger T, Lang RE, Scholkens BA, Ganten D. Tissue renin-angiotensin systems: focus on the heart. J Hypertens. 1987;5:33-38.
2. Bunnemann B, Fuxe K, Ganten D. The brain renin-angiotensin system: localization and general significance. J Cardiovasc Pharmacol. 1992;19:S51-S62.
3.
Sigmund CD, Jones CA, Kane CM, Wu C, Lang JA, Gross KW.
Regulated tissue- and cell-specific expression of the human renin gene
in transgenic mice. Circ Res. 1992;70:1070-1079.
4. Fukamizu A, Seo MS, Hatae T, Yokoyama M, Nomura T, Katsuki M, Murakami K. Tissue-specific expression of the human renin gene in transgenic mice. Biochem Biophys Res Commun. 1989;165:826-832. [Medline] [Order article via Infotrieve]
5.
Fukamizu A, Sugimura K, Takimoto E, Sugiyama F, Seo M-S,
Takahashi S, Hatae T, Kajiwara N, Yagami K, Murakami K. Chimeric
renin-angiotensin system demonstrates sustained increase in blood
pressure of transgenic mice carrying both human renin and human
angiotensinogen genes. J Biol Chem. 1993;268:11617-11621.
6.
Sigmund CD, Gross KW. Structure, expression, and regulation
of murine renin genes. Hypertension. 1991;18:446-457.
7.
Sigmund CD, Okuyama K, Ingelfinger J, Jones CA, Mullins JJ,
Kim U, Kane-Haas C, Wu C, Kenney L, Rustum Y, Dzau V, Gross KW.
Isolation and characterization of renin expressing cell lines from
transgenic mice containing a renin promoter viral oncogene fusion
construct. J Biol Chem. 1990;265:19916-19922.
8.
Duncan KG, Haidar MA, Baxter JD, Reudelhuber TL. Regulation
of human renin expression in chorion cell primary cultures. Proc
Natl Acad Sci U S A. 1990;87:7588-7592.
9.
Borensztein P, Germain S, Fuchs S, Philippe J, Corvol P,
Pinet F. cis-Regulatory elements and trans-acting factors directing
basal and cAMP-stimulated human renin gene expression in chorionic
cells. Circ Res. 1994;74:764-773.
10. Kawai K, Fukamizu A, Kawakami Y, Matsumura M, Mitsui K, Murakami K, Yamashita K. A case of renin producing leiomyosarcoma originating from the lung. Endocrinol Jpn. 1991;38:603-609. [Medline] [Order article via Infotrieve]
11. Genest J, Rojo-Ortega JM, Kuchel O, Boucher R, Nowaczynski W, Lefebvre R, Chretien M, Cantin J, Granger P. Malignant hypertension with hypokalemia in a patient with renin-producing pulmonary carcinoma. Trans Assoc Am Physicians. 1975;88:192-200. [Medline] [Order article via Infotrieve]
12. Taylor GM, Cook HT, Sheffield EA, Hanson C, Peart WS. Renin in blood vessels in human pulmonary tumors: an immunohistochemical and biochemical study. Am J Pathol. 1988;130:543-551. [Abstract]
13. Taylor GM, Cook HT, Hanson C, Peart WS, Zondek T, Zondek LH. Renin in human fetal lung: a biochemical and immunohistochemical study. J Hypertens. 1988;6:845-851. [Medline] [Order article via Infotrieve]
14. Sigmund CD. Expression of the human renin gene in transgenic mice throughout ontogeny. Pediatr Nephrol. 1993;7:639-645. [Medline] [Order article via Infotrieve]
15.
Burson JM, Aguilera G, Gross KW, Sigmund CD. Differential
expression of angiotensin receptor 1A and 1B in mouse. Am J
Physiol. 1994;267:E260-E267.
16. Chomczynski P, Sacchi N. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal Biochem. 1987;161:156-159.
17. Ausubel FM, Brent R, Kingston RE, Moore DD, Seidman JG, Smith JA, Struhl K. Current Protocols in Molecular Biology. New York, NY: John Wiley & Sons; 1989.
18. Wohlford-Lenane CL, Durham PL, Snyder JM. Localization of surfactant-associated protein C (SP-C) mRNA in fetal rabbit lung tissue by in situ hybridization. Am J Respir Cell Mol Biol. 1992;6:225-234.
19. Wohlford-Lenane CL, Snyder JM. Localization of surfactant-associated proteins SP-A and SP-B mRNA in rabbit fetal lung tissue by in situ hybridization. Am J Respir Cell Mol Biol. 1992;7:335-343.
20. Weintraub H, Cheng PF, Conrad K. Expression of transfected DNA depends on DNA topology. Cell. 1986;46:115-122. [Medline] [Order article via Infotrieve]
21.
Jones CA, Sigmund CD, McGowan R, Kane-Haas C, Gross KW.
Temporal and spatial expression of the murine renin genes during fetal
development. Mol Endocrinol. 1990;4:375-383.
22.
Gomez RA, Lynch KR, Chevalier RL, Wilfong N, Everett A, Carey
RM, Peach MJ. Renin and angiotensinogen gene expression in maturing rat
kidney. Am J Physiol. 1988;254:F582-F587.
23. Baxter JD, Duncan K, Chu W, James MN, Russell RB, Haidar MA, DeNoto FM, Hsueh WA, Reudelhuber TL. Molecular biology of human renin and its gene. Recent Prog Horm Res. 1993;47:211-257.
24.
Sun J, Oddoux C, Gilbert MT, Yan Y, Lazarus A, Campbell WG,
Catanzaro DF. Pituitary-specific transcription factor (Pit-1) binding
site in the human renin gene 5'-flanking DNA stimulates promoter
actvity in placantal cell primary cultures and pituitary
lactosomatotropic cell lines. Circ Res. 1994;75:624-629.
25.
Horiuchi M, Nakamura N, Tang SS, Barrett G, Dzau VJ.
Molecular mechanism of tissue-specific regulation of mouse renin gene
expression by cAMP: identification of an inhibitory protein that binds
nuclear transcriptional factor. J Biol Chem. 1991;266:16247-16254.
26.
Ekker M, Tronik D, Rougeon F. Extra-renal transcription of the
renin genes in multiple tissues of mice and rats. Proc Natl Acad
Sci U S A. 1989;86:5155-5158.
27.
Lynch KR, Peach MJ. Molecular biology of angiotensinogen.
Hypertension. 1991;17:263-269.
28.
Saye JA, Cassis LA, Sturgill TW, Lynch KR, Peach MJ.
Angiotensinogen gene expression in mouse 3T3-L1 cells. Am J
Physiol. 1989;256:C448-C451.
29. Pinet F, Mizrahi J, Laboulandine I, Menard J, Corvol P. Regulation of prorenin secretion in cultured human transfected juxtaglomerular cells. J Clin Invest. 1987;80:724-731.
30. Pinet F, Corvol MT, Dench F, Bourguignon J, Feunteun J, Menard J, Corvol P. Isolation of renin-producing human cells by transfection with 3 simian virus 40 mutants. Proc Natl Acad Sci U S A. 1988;82:8503-8507.
31.
Burt DW, Nakamura N, Kelley P, Dzau VJ. Identification of
negative and positive regulatory elements in the human renin gene.
J Biol Chem. 1989;264:7357-7362.
32. Black TA, Abonia JP, Fabian JR, Kane CM, Sigmund CD, Gross KW. cis-Acting DNA elements regulating mouse renin gene expression. Hypertension. 1993;22:408. Abstract.
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 R. Mrowka, A. Steege, C. Kaps, H. Herzel, B. J. Thiele, P. B. Persson, and N. Bluthgen Dissecting the action of an evolutionary conserved non-coding region on renin promoter activity Nucleic Acids Res., August 1, 2007; 35(15): 5120 - 5129. [Abstract] [Full Text] [PDF]
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 M. Hautmann, U. G. Friis, M. Desch, V. Todorov, H. Castrop, F. Segerer, C. Otto, G. Schutz, and F. Schweda Pituitary Adenylate Cyclase-Activating Polypeptide Stimulates Renin Secretion via Activation of PAC1 Receptors J. Am. Soc. Nephrol., April 1, 2007; 18(4): 1150 - 1156. [Abstract] [Full Text] [PDF]
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H. A. Itani, X. Liu, J. H. Pratt, and C. D. Sigmund Functional Characterization of Polymorphisms in the Kidney Enhancer of the Human Renin Gene Endocrinology, March 1, 2007; 148(3): 1424 - 1430. [Abstract] [Full Text] [PDF]
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 L. Pan, S. T. Glenn, C. A. Jones, and K. W. Gross Activation of the Rat Renin Promoter by HOXD10{middle dot}PBX1b{middle dot}PREP1, Ets-1, and the Intracellular Domain of Notch J. Biol. Chem., May 27, 2005; 280(21): 20860 - 20866. [Abstract] [Full Text] [PDF]
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 M. Sherrod, X. Liu, X. Zhang, and C. D. Sigmund Nuclear localization of angiotensinogen in astrocytes Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2005; 288(2): R539 - R546. [Abstract] [Full Text] [PDF]
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 L. Pan and K. W. Gross Transcriptional Regulation of Renin: An Update Hypertension, January 1, 2005; 45(1): 3 - 8. [Abstract] [Full Text] [PDF]
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M. Loghman-Adham, C. E. Soto, T. Inagami, and L. Cassis The intrarenal renin-angiotensin system in autosomal dominant polycystic kidney disease Am J Physiol Renal Physiol, October 1, 2004; 287(4): F775 - F788. [Abstract] [Full Text] [PDF]
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 R. Nistala, X. Zhang, and C. D. Sigmund Differential expression of the closely linked KISS1, REN, and FLJ10761 genes in transgenic mice Physiol Genomics, March 12, 2004; 17(1): 4 - 10. [Abstract] [Full Text] [PDF]
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P. L. SINN and C. D. SIGMUND Identification of three human renin mRNA isoforms from alternative tissue-specific transcriptional initiation Physiol Genomics, June 29, 2000; 3(1): 25 - 31. [Abstract] [Full Text] [PDF]
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P. L. Sinn, X. Zhang, and C. D. Sigmund JG cell expression and partial regulation of a human renin genomic transgene driven by a minimal renin promoter Am J Physiol Renal Physiol, October 1, 1999; 277(4): F634 - F642. [Abstract] [Full Text] [PDF]
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 Q. Shi, T. A. Black, K. W. Gross, and C. D. Sigmund Species-Specific Differences in Positive and Negative Regulatory Elements in the Renin Gene Enhancer Circ. Res., September 17, 1999; 85(6): 479 - 488. [Abstract] [Full Text] [PDF]
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P. L. Sinn and C. D. Sigmund Human Renin mRNA Stability Is Increased in Response to cAMP in Calu-6 Cells Hypertension, March 1, 1999; 33(3): 900 - 905. [Abstract] [Full Text] [PDF]
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S. Germain, F. Bonnet, J. Philippe, S. Fuchs, P. Corvol, and F. Pinet A Novel Distal Enhancer Confers Chorionic Expression on the Human Renin Gene J. Biol. Chem., September 25, 1998; 273(39): 25292 - 25300. [Abstract] [Full Text] [PDF]
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L. Ying, B. J. Morris, and C. D. Sigmund Transactivation of the Human Renin Promoter by the Cyclic AMP/Protein Kinase A Pathway Is Mediated by Both cAMP-responsive Element Binding Protein-1 (CREB)-dependent and CREB-independent Mechanisms in Calu-6 Cells J. Biol. Chem., January 24, 1997; 272(4): 2412 - 2420. [Abstract] [Full Text] [PDF]
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M. W. Thompson, S. B. Smith, and C. D. Sigmund Regulation of Human Renin mRNA Expression and Protein Release in Transgenic Mice Hypertension, August 1, 1996; 28(2): 290 - 296. [Abstract] [Full Text]
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