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At least 235 records · Page 13Linked to original sources
PubMed2003

Detection of nonmelanoma skin cancer micrometastases in lymph nodes by using reverse transcriptase-polymerase chain reaction for keratin 19 mRNA.

BACKGROUND: A new sensitive method for the detection of skin cancer micrometastases in lymph nodes is based on amplification of keratin 19 (K19) mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR). OBJECTIVES: To compare results of RT-PCR with those of histological examination in terms of the detection rate of skin cancer micrometastases. METHODS: Twenty-six lymph nodes obtained from 13 patients with squamous cell carcinoma (SCC), eccrine porocarcinoma and Paget's disease were investigated by histological examination (haematoxylin and eosin sections) and RT-PCR. RT-PCR was performed on extracted RNA by using K19 primer pairs. RT-PCR products were visualized by ethidium bromide staining and confirmed by non-radioactive hybridization with K19-specific probes. RESULTS: All of 10 histologically positive lymph nodes yielded the expected 460-bp band. Of the 16 histologically negative lymph nodes, one (6%) was found by RT-PCR to express K19 mRNA, indicating the presence of micrometastases which could not be detected by histological examination. A serial dilution study using RNA extracted from SCC cells mixed with RNA extracted from normal lymph node cells showed a detection sensitivity of K19 RT-PCR of 10-5 micro g cancer cell RNA in 1 micro g lymph node RNA. Nested RT-PCR showed a detection sensitivity of one tumour cell in 106 lymphocytes. CONCLUSIONS: These results demonstrate the usefulness of K19 RT-PCR for the detection of skin cancer micrometastases in lymph nodes.

Biomarkers, Tumor↗
PubMed1996

Detection of hepatitis B virus DNA and RNA in kidneys of HBV related glomerulonephritis.

Glomerular deposition of hepatitis B virus (HBV) antigens are observed in chronic HBsAg carriers with different glomerulonephritides yet the etiologic role of HBV remains uncertain. We examined the paraffin section of kidney biopsies from 40 chronic HBsAg carriers with membranous nephropathy (MGN), mesangiocapillary glomerulonephritis (MCGN) or IgA nephropathy (IgAN) for HBV DNA and HBV RNA using in situ hybridization (ISH). Glomerular HBV antigens were present in all biopsies by immunofluorescence. HBsAg or HBcAg mRNA was also studied in RNA extracted from frozen renal tissue using a two-step polymerase chain reaction (PCR) following reverse transcription (RT). HBcAg DNA was not easily detected with ISH alone, but was readily found in 31 biopsies (78%) following PCR. HBV DNA was detected mainly in the cytoplasm of proximal tubular epithelia but not in glomerular cells. HBsAg and/or HBcAg mRNA were detected by RT-PCR in extracted RNA from 13 biopsies (33%). The PCR findings were further confirmed by (a) Southern blot hybridization using a cloned HBV probe and (b) absence of PCR product following treating RNA with RNase or omitting the RT. It is plausible that HBV DNA in renal tubules represents endocytosis of HBV DNA in the urinary filtrate and the HBV RNA extracted from kidney biopsies could derive from infiltrating cells bearing HBV RNA. Hence, ISH with specific HBV core gene RNA probe was performed subsequently. HBcAg RNA, localized in the nuclei and cytoplasm of glomerular and tubular cells, was detected in 56%, 20%, and 36% of renal biopsies in chronic HBsAg carriers with MGN, MCGN, and IgAN, respectively. Our findings indicate the presence of viral transcription in glomerular cells and renal tubular epithelia, supporting an etiological role of HBV in some chronic HBsAg carriers who develop coexisting glomerulonephritides.

Adolescent↗
PubMed1969

Partial characterization of the RNA stimulating growth of the seminal vesicle.

RNA prepared from the seminal vesicles of intact adult rats, or of testosterone-treated castrate adult rats, produced a 30 per cent increase in the weight of the seminal vesicle and a 25 per cent increase in the incorporation of labeled amino acids into protein. RNA prepared from the liver or ventral prostate of the same animals produced only a 10 per cent increase in the weight of the seminal vesicle. RNA prepared from the liver of control or testosterone-treated adult female rats was ineffective in stimulating the growth of the seminal vesicle. Polyuridylic acid instilled into the lumen had no effect on the weight of the seminal vesicle, but increased the incorporation of labeled phenylalanine into protein. RNA sedimenting in the 18S area on sucrose density gradients was most effective in stimulating growth of the seminal vesicle of three-week-old rats. Treating homogenized tissue with deoxycholate greatly increased the effectiveness of the RNA extracted. RNA extracted from seminal vesicles by treatment with deoxycholate and dextran sulfate was biologically active, whereas the usual 4S RNA in the 100,000 x g supernatant is ineffective.

Animals↗
PubMed2006

Extraction of RNA from archival tissues and measurement of thrombospondin-1 mRNA in normal, dysplastic, and malignant oral tissues.

Thrombospondin-1 (TSP-1) is an extracellular matrix glycoprotein implicated in the regulation of angiogenesis and tumour development. Our objectives were to ascertain the quantity and quality of RNA extracted from archival, formalin-fixed, paraffin embedded, oral tissues and their application in measuring the concentrations of TSP-1 mRNA in these tissues. We compared three techniques of isolation of RNA as well as related experimental variables. TSP-1 mRNA was measured in specimens of normal, dysplastic, and malignant oral tissues by real-time reverse transcriptase polymerase chain reaction (RT-PCR). RNA suitable for analysis by real-time RT-PCR was obtained by the three techniques tested, although the yield varied depending on the protocol used (range 0.2-3.6 microg/mm(3)). The mean (S.D.) concentrations of TSP-1 mRNA relative to 18S were 21.1 (7.2) in normal oral tissues (n=9), 11.0 (8.2) in dysplastic tissue (n=8) and 7.3 (5.3) in carcinomatous tissue (n=17). The difference between normal and carcinomatous specimens was significant (p=0.01). This reduction in expression of TSP-1 mRNA from normal to dysplasia to carcinoma may favour the angiogenic drive that accompanies the development of oral tumours.

Carcinoma, Squamous Cell↗
PubMed1997

Detection of coxsackievirus B3 in intestinal tissue of orally-infected mice by a standardized RT-PCR assay.

BACKGROUND: Previous studies have reported the role of enteroviruses in chronic diseases, using in-house RT-PCR protocols. A well-standardized PCR assay (Amplicor enterovirus, Produits Roche) designed for the diagnosis of enterovirus meningitis in cerebrospinal fluids (CSF) was recently described. OBJECTIVES: To evaluate this commercially-available PCR assay for the detection of enterovirus in intestinal biopsies. STUDY DESIGN: In order to obtain large quantities of infected material, eight mice were inoculated orally with 2 x 10(5) 50% tissue culture infective doses (TCID50) of coxsackievirus B3 (CBV3); two mice were sacrificed every day from day 1 to day 4 post-infection. Stool specimens and small bowel fragments were taken from infected animals and controls. Four protocols of RNA extraction from intestinal tissue were compared. Extracted RNA was then tested by the Amplicor assay and by a seminested in-house PCR. RESULTS: The best results were obtained with a commercial reagent using a combination of guanidium thiocyanate and phenol (TRI Reagent, Sigma). This procedure allowed the detection of enteroviral RNA in intestinal samples of 7/8 and 8/8 infected mice by Amplicor assay and seminested PCR, respectively, whereas only five samples were tested positive by conventional cell culture. When tested on serial dilutions of CBV3 mixed with intestinal tissue, a sensitivity of 0.2 TCID50/mg was achieved with both PCR assays. CONCLUSIONS: The data demonstrate that the Amplicor enterovirus assay, which is designed to avoid false-positive amplifications, can be used, with a slight modification of the RNA extraction step, for the detection of enterovirus in specimens different from CSF such as intestinal tissue.

Animals↗
PubMed2004

Extraction of total RNA from Chrysanthemum containing high levels of phenolic and carbohydrates.

Some standard methods are available in total RNA extraction of plant tissue, which are effective for the ordinary plants. But it is difficult to extract the total RNA from the plants with high levels of phenolic compounds, carbohydrates, or other compounds that bind and/or coprecipitate with RNA. In this paper, a method was described that used the soluble polyvinylpyrrolidone (PVP), ethanol precipitation, phenol extraction and LiCl precipitation. By this method, RNA capable of reverse-transcription and polymerase chain reaction (PCR) amplification was isolated from Chrysanthemum that contains high levels of phenolic compounds and carbohydrates. The OD260/OD280 absorbance ratio is 2, and the RNA is intact. Other specialized RNA extraction methods failed to deliver suitable product. Bands of PCR products are clearly appearing on the polypropylene acyl gel electrophoresis (PAGE) gel, which indicates that the purity, concentration and integrity of total RNA were suitable for the sequent researches.

Carbohydrates↗
PubMed2001

[Extraction of RNA from paraffin embedded tissues and analysis of p53 gene expression in colonic cancer].

We examined, immunohistochemically and molecular biologically, p53 gene expression in 10 patients with colonic cancer. RNA was extracted from paraffin embedded normal and colonic cancer tissues by using RNA isolator kit and proteinase K. The most effective time and concentration of proteinase K for RNA extraction was 24 hours and 100 micrograms/ml, respectively. P53 gene expression was analyzed by ABI PRISM 7700 Sequence Detection System(ABI 7700 System, Perkinelmer). Gene expression level in each sample was estimated on the basis of the standard curve of ABI 7700 System. Human G3PDH gene was used as the internal control. Immunohistochemically, the tumor cells in all examined cases showed a strong positivity for anti-p53 gene antibody. In ABI 7700 System, expression of p53 gene in the malignant tissues revealed a high level in only 2 cases that had a clinical stage IV, however, in remaining 8 cases a clinical stage was I to III and expression level of p53 was relatively lower. These results suggest that colonic cancer cells show mutant-p53 gene expression, and a ratio of mutant- to wild-p53 gene may have something to do with a relationship between gene expression and clinical stage.

Adenocarcinoma↗
PubMed1987

Biosynthesis of the low molecular weight carrier protein for insulin-like growth factors in rat liver and fibroblasts.

Biosynthesis of the low mol wt (Mr) carrier protein for insulin-like growth factors (IGFs) was studied in the BRL-3A rat liver cell line, rat embryo fibroblasts (REFs), and fetal rat liver by biosynthetic labeling of intact cells and cell-free translation of extracted RNA. [35S]Cysteine-labeled carrier protein precursors were immunoprecipitated using antibodies raised to the approximately 33,000 Mr carrier protein from BRL-3A cells that recognize the IGF carrier protein present in fetal and neonatal rat serum, but not in adult rat serum. The IGF carrier protein is synthesized as a 35,000 Mr precursor in a reticulocyte lysate translation system directed by RNA from BRL-3A cells or REFs. Supplementation of the translation incubation with microsomal membranes decreases the size of the precursor to 33,000 Mr, presumably by removal of a signal peptide. In continuous labeling or pulse-chase experiments of intact BRL-3A cells or REFs, the 33,000 Mr protein is labeled within 10 min intracellularly, appears in the medium after 40 min, and persists in the medium for 24 h without a change in size. The intracellular carrier protein was biosynthetically labeled in BRL-3A cells with [3H]leucine, [3H]phenylalanine, [3H]arginine, or [35S]cysteine and purified, and its NH2-terminal amino acid sequence was determined. Eleven of 34 residues were identified and correspond to those of mature unlabeled carrier protein purified from conditioned medium, indicating that after removal of the signal peptide, the carrier protein undergoes no detectable further processing at its NH2-terminus. These results establish that although they are regulated coordinately, IGF-II and the fetal IGF carrier protein are synthesized as separate proteins. Finally, RNA extracted from fetal, but not adult, rat liver directs the synthesis of the 35,000 Mr carrier protein precursor, suggesting that the developmental regulation of the carrier protein may occur at the level of RNA abundance.

Amino Acid Sequence↗
PubMed1993

Purification of murine Kupffer cells by centrifugal elutriation.

Procedures to reproducibly obtain pure preparations of murine Kupffer cells are described. Pure Kupffer cell preparations obtained following collagenase digestion, metrizamide separation and centrifugal elutriation remained viable and maintained their phagocytic functions for at least 4-5 days in vitro. Furthermore, we determined the feasibility of extracting RNA from Kupffer cells obtained immediately following elutriation and after 2 and 4 days of culture in vitro. These RNA extracts were used to determine the level of cytokine gene expression in Kupffer cells.

Animals↗
PubMed1999

Effects of EGF and TGFbeta1 on c-myc gene expression and DNA synthesis in embryonic hamster palate mesenchymal cells.

Previous work has shown that cell proliferation is a major contributor to the early palate morphogenesis in mammals. The present study was undertaken to examine the effect of EGF, TGFbeta1 and their combination on proliferation (measured by DNA synthesis) and on the expression of a growth related proto-oncogene, c-myc, in embryonic hamster palate mesenchymal cells (HPMC). Vertically developing hamster palatal shelves were dissected on day 11 of gestation, and trypsinized, and primary cultures were grown in DMEM + 10% serum at 37 degrees C and 5% CO2. Following appropriate growth factor treatment of HPMC, DNA synthesis was measured by scintillation counting and extracted RNA was subjected to Northern blot analysis. In serum-starved, pre-confuent cultures treated with EGF (20 ng/ml), DNA synthesis was stimulated in the presence of 2.5% serum. In contrast, treatment of HPMC with TGFbeta1 (10 ng/ml) in the presence or absence of EGF/serum for 24 hr, or HPMC pre-treatment with TGFbeta1 (30 min) followed by EGF/serum (24 hr), resulted in an arrest of DNA synthesis. Northern blot analysis of RNA extracted from HPMC showed that as serum-starved, growth-arrested cells progressed through G0 to G1 phase of the cell cycle, following EGF treatment, c-myc was expressed by 1 hr and declined thereafter. In contrast, TGFbeta1 did not support expression of c-myc. Following pre- or co-treatment with TGFbeta1, the EGF +/- serum-induced expression of c-myc was seen between 1 and 6 hr. It appears that EGF-induced expression of c-myc may be involved in advancing the HPMC in G1, and thus may contribute to the onset of DNA synthesis in HPMC. Since co- or pre-treatment with TGFbeta1 did not inhibit EGF/serum induced expression of c-myc, it is possible that growth arresting effect of TGFbeta1 may not be exerted directly through inhibition or blockage of c-myc expression.

Animals↗
PubMed1996

Hepatic expression of hepatitis C virus RNA in chronic hepatitis C: a study by in situ reverse-transcription polymerase chain reaction.

Hepatitis C virus (HCV) replicates at a low rate and this makes its detection and intrahepatic localization difficult. To evaluate the clinical implications and effect of interferon alfa (IFN-alpha) therapy on hepatic expression of HCV RNA, HCV RNA was detected by in situ reverse-transcription polymerase chain reaction (IS-RT-PCR) in formalin-fixed paraffin-embedded liver sections from 26 patients with chronic hepatitis C. Results were compared with RT-PCR of HCV RNA extracted from liver sections/tissue. Twenty-four paired post-IFN-alpha treatment biopsy specimens were also assessed. Using RT-PCR of the extracted RNA as a positive standard and non-HCV liver sections as the negative standard, the sensitivity and specificity of IS-RT-PCR were 69% and 100%, respectively. HCV RNA was detected in the cytoplasm of hepatocytes (median, 5% hepatocytes positive; range, 0 to 35%) and very occasionally in infiltrating mononuclear cells. There was no correlation between hepatic expression of HCV RNA and the clinical, biochemical parameters, total and activity scores of histology activity index. Presence of HCV RNA in liver as detected by IS-RT-PCR was associated with higher serum HCV RNA levels (4.9 x 10(6) vs. 0.4 x 10(6) genome Eq/mL, P < .01). There was no difference in the pretreatment proportion of HCV RNA-positive hepatocytes among patients with different biochemical responses to IFN-alpha therapy. In the posttreatment samples, HCV RNA was undetectable by IS-RT-PCR in 16 of 24 patients (P < .01), including all 4 patients who had complete and sustained response (SR). We conclude that HCV RNA was detected by IS-RT-PCR in 0 to 35% of hepatocytes in patients with chronic HCV infection, detection of HCV RNA in liver by IS-RT-PCR was associated with higher viremia levels and IFN-alpha therapy reduced hepatocytic expression of HCV RNA.

Adult↗
PubMed1991

Identification of viral proteins encoded by two DNA fragments of herpesvirus of turkeys (HVT).

Herpesvirus of turkeys (HVT) vaccine is used worldwide to immunize chickens against Marek's disease (MD). Polyclonal antiserum directed against one virus cross-reacts with proteins of the other, while only 5% homology at the DNA level was demonstrated between the two viruses. A partial library of HVT DNA fragments ranging from 1.5 to 13.5 kbp in size was constructed in pBR 322. Under stringent conditions of hybridization (low salt concentration, 10% dextran sulfate at 68 degrees C), two of the cloned HVT DNA fragments (13.5 and 11.0 kbp) hybridized to three MDV DNA fragments: BamHI-C, D, and G. The 13.5 kbp fragment detected two transcripts of 1.8 and 3.0 kb in RNA extracted from HVT-infected chicken embryo fibroblasts, while the 11.0 kbp fragment detected three transcripts of 1.6, 2.0, and 3.0 kb in the extracted RNA. Using hybrid selection, specific RNA was isolated by hybridization with the two cloned HVT DNA fragments and then was translated in vitro using rabbit reticulocyte lysate, and the resulting proteins were analyzed by NaDodSO4-PAGE. The RNA selected by the two HVT DNA fragments coded for a 30 kD protein and for several smaller proteins 10-20 kD in size, while the RNA selected by the 11.0 kb HVT DNA fragment was translated into a 40 kD protein. Immunoprecipitation of these in vitro synthesized proteins with hyperimmune anti-HVT chicken serum showed that they were of viral origin.

Animals↗
PubMed1992

Direct application to dairy foods of a Listeria-specific oligonucleotide probe to 16S rRNA.

A potentially Listeria-specific 28 base oligonucleotide probe was designed from 16S rRNA sequence data. Using either 32P or non-radioactive (alkaline phosphatase) labels, the probe was shown to be highly specific as it hybridised to RNA extracted from all of the species of Listeria but not to any of the other bacteria tested. Both probe methods were highly sensitive and ca 10(2) cfu/ml Listeria could be detected in pure cultures. A rapid procedure for extracting RNA from milk, Camembert and cottage cheese was developed. This allowed the direct application of the probe to these foods and gave a rapid and specific method of detecting > 10(2) cfu/g or ml Listeria in these foods.

Base Sequence↗
PubMed2006

A simple and convenient approach for isolating RNA from highly viscous plant tissue rich in polysaccharides.

RNA isolation is a prerequisite to the study of gene expression of herbaceous plant Dendrobium nobile under an environmental stress. However, RNA isolation is difficult in the plant of genus Dendrobium, which is relatively viscous, due to being rich in polysaccharides. The common protocols for RNA isolation are tedious and usually result in poor yields when applied to D. nobile. Here, we describe a simple and convenient method for high quality total RNA extraction from D. nobile. Main procedures are as follows: smashing plant tissue and cell wall by means of pre-cooled citrate homogenization, cleaving cell membrane by using guanidine hydrochloride lysis buffer, removing proteins, polyphenols and polysaccharides by acidic phenol/chloroform. It is particularly useful for processing large numbers of plant samples. The whole process can be completed within 2.5 h. The extracted RNA is suitable for applications such as RT-PCR, Northern analysis and screening of differential expression genes.

Cell Culture Techniques↗
PubMed2005

A simple wax-embedding method for isolation of aphid hemolymph for detection of luteoviruses in the hemocoel.

A protocol for isolating hemolymph from viruliferous aphids has been developed. This method uses warm melted wax to immobilize the aphid. Following removal of a hind leg, the hemolymph can be collected readily. Flushing with RNase-free water allows for collection of sufficient hemolymph for RNA extraction from individual aphids. The extracted RNA was successfully used for detection of barley yellow dwarf virus (BYDV) and pea enation mosaic virus (PEMV) from individual viruliferous Rhopalosiphum padi and Acyrthosiphon pisum aphids, respectively. A TaqMan real-time RT-PCR protocol for quantitation of PEMV in the hemolymph of individual aphids was developed. The wax-embedding hemolymph collection technique provides a useful tool for studying molecular interactions between persistent and circulative plant viruses and their insect vectors.

Animals↗
PubMed1997

Enteroviral RNA and virus-like particles in the skeletal muscle of patients with idiopathic dilated cardiomyopathy.

The role of chronic viral infection in the etiopathogenesis of idiopathic dilated cardiomyopathy (IDC) has generated considerable research. Enteroviruses were the favorite candidates as etiologic agents of IDC. However, enteroviruses were rarely demonstrated in affected hearts. We investigated whether enteroviral infection persists in the heart and in extracardiac sites, particularly in skeletal muscle, in patients with IDC. Blood and myocardial and skeletal muscle samples were collected at cardiac transplantation from 31 IDC patients, 24 non-IDC heart disease patients, and 3 heart donors. Samples underwent ultrastructural studies and ribonucleic acid (RNA) extraction. RNA was reverse-transcribed, and 2 nested fragments (bps 179 and 126) were amplified in the highly conserved 5' noncoding region of enteroviral genomic RNA. Enteroviral RNA was found in the skeletal muscle of 12 cases, whereas only 4 hearts (2 of which with positive skeletal muscle) were positive. Of the 24 controls, 2 were positive (1 muscle and heart, 1 muscle only). Automated sequencing confirmed the enteroviral nature of the amplified products. Ultrastructural study showed enterovirus-like particles in 4 of the enterovirus-positive muscles, and myopathic changes in all enterovirus-positive cases. Skeletal muscle hosts chronic enteroviral infection in more than one third of patients with sporadic IDC. Two hypotheses may explain this link. Myocardial damage may derive directly from recurrent subclinical heart infections caused by enteroviruses harbored in skeletal muscle. Alternatively, enterovirus-related myopathy may trigger an autoimmune response to antigens shared by muscle and myocardium. Further studies are needed to assess the importance of these, non-mutually exclusive mechanisms in IDC pathogenesis.

Adult↗
PubMed2002

Changes in differential gene expression because of warm ischemia time of radical prostatectomy specimens.

The expression of thousands of genes can be monitored simultaneously using cDNA microarray technology. This technology is being used to understand the complexity of human disease. One significant technical concern regards potential alterations in gene expression because of the effect of tissue ischemia. This study evaluates the increase in the differential gene expression because of tissue processing time. To evaluate differential gene expression because of ischemia time, prostate samples were divided into five time points (0, 0.5, 1, 3, and 5 hours). Each time point consisted of a homogeneous mixture of 12 to 15 prostate tissue cubes (5 mm(3)). These tissues were maintained at room temperature until at the assigned time point the tissue was placed in OCT, flash frozen in liquid nitrogen, and stored at -80 degrees C until RNA extraction. RNA from each time point was hybridized against an aliquot of 0 time point RNA from the same prostate. Four prostate glands were used in parallel studies. M-A plots were graphed to compare variability between time point sample hybridizations. Statistical Analysis of Microarray software was used to identify genes overexpressed at the 1-hour time point versus the 0-hour time with statistically significance. Microarray analysis revealed only a small percentage of genes (<0.6%) from more than 9000 to demonstrate overexpression at the 1-hour time point. Among the 41 statistically significant named overexpressed genes at the 1-hour time point were early growth response 1 (EGR1), jun B proto-oncogene (jun B), jun D proto-oncogene (jun D), and activating transcription factor 3 (ATF3). Genes previously associated with prostate cancer did not have significantly altered expression with ischemia time. Increased EGR1 protein expression was confirmed by Western blot analysis. Microarray technology has opened the possibility of evaluating the expression of a multitude of genes simultaneously, however, the interpretation of this complex data needs to be assessed circumspectly using refined statistical methods. Because RNA expression represents the tissue response to insults such as ischemia, and is also sensitive to degradation, investigators need be mindful of confounding artifacts secondary to tissue processing. All attempts should be made to process tissue rapidly to ensure that the microarray gene profile accurately represents the state of the cells and confirmatory studies should be performed using alternative methods (eg, Northern blot analysis, Western blot, immunohistochemistry).

Artifacts↗
PubMed2006

Global gene expression patterns in mouse wolffian duct development.

PURPOSE: We identified genes responsible for terminal differentiation of the mouse ureter. MATERIALS AND METHODS: We isolated the wolffian ducts of Black Swiss mice from embryonic days 12.5 to 14.5. These ducts were processed for total RNA extraction. RNA was amplified and converted to biotinylated cDNA, which was hybridized to Affymetrix(R) mouse 430 microarray GeneChips. Data were analyzed using Affymetrix software provided by the core facility at our institution. Data were confirmed by semiquantitative polymerase chain reaction and immunohistochemistry. RESULTS: Of 42,000 evaluable transcripts 412 were up-regulated and 133 were down-regulated more than 1.5-fold between embryonic days 12.5 and 14.5. Of up-regulated genes 17 were up-regulated more than 3-fold. Of these genes 5 were selected for further study and they were identified as having roles in cell growth/regulation in general. Increased expression of Foxa1 was seen at embryonic day 14.5 in the distal ureter and urogenital sinus. CONCLUSIONS: To our knowledge this is the first report of differential gene expression patterns in the developing mouse wolffian duct. Our results diverge from expression patterns reported in the kidney. This information will enable future comparisons between WT and transgenic mice with an abnormal phenotype.

Animals↗