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D F Catanzaro

Publications and source records attributed to D F Catanzaro.

At least 37 records · Page 2Linked to original sources
PubMed1991

Sp1 and thyroid hormone receptor differentially activate expression of human growth hormone and chorionic somatomammotropin genes.

Activation of hGH-1 expression is mediated by the pituitary-specific transcription factor GHF-I/Pit-I which binds the 5'-flanking DNA at two sites: I (-96/-70) and II (-134/-106). Although the factor(s) which direct the placental-specific expression of hCS-1 are not known, hCS-1 sequences are transcriptionally active in pituitary cells. In the present study we examined the effects of sequence differences between hGH-1 and hCS-1 5'-flanking DNAs in determining their basal and thyroid hormone-regulated promoter activities. We showed that Sp1 is a major determinant of both hGH-1 and hCS-1 promoter activities and that in hGH-1, binding and activation by Sp1 are modulated by interference from GHF-I/Pit-1 binding at the adjacent site II sequence. A single base which differed in site II of hCS-1 greatly reduced GHF-1/Pit-1 binding and thus facilitated binding and activation by Sp1. Further differences in promoter activity of hGH-1 and hCS-1 sequences were accounted for by a thyroid hormone-responsive element between -62/-48 in the hCS-1 gene. However, induction by T3 was independent of either Sp1 or GH-1/Pit-1 binding in the site II region. These data demonstrate that a small number of base changes between hGH and hCS promoter sequences subserve a number of mechanisms which may differentially modulate the expression of hGH and hCS genes.

Base Sequence↗
PubMed1991

Interactions between rat prolactin gene promoter and enhancer regions in mammosomatotrope and lactotrope cell lines.

Although both promoter and enhancer sequences of the PRL gene 5'-flanking DNA are required for cell-specific, high level expression in transgenic animals, reports of the relative contributions of these elements determined in transient transfection experiments have varied. In this study we examined the transcriptional activities of proximal promoter (-422/+33) and distal enhancer (-1956/-1530) sequences of the rat (r) PRL gene by transient transfection of hybrid genes containing these sequences into two rat pituitary cell lines, GC and 235-1. These cell lines exhibit characteristics either of mammosomatotropes, which express both PRL and the evolutionarily related GH gene (GC), or lactotropes, which express only PRL (235-1). As lactotropes are thought to differentiate from a mammosomatotrope precursor cell, comparisons between these cell lines provide the opportunity to examine the mechanisms that activate PRL and GH genes during development. We show that the relative contributions of promoter and enhancer elements differ between GC and 235-1 cells. Although maximal enhancer-driven activity was similar between these cell lines, promoter sequences were more active in GC (5-10% maximal) than 235-1 cells (1-2% maximal). However, no apparent differences in factor binding to the rPRL promoter region could be correlated with differences in activity, suggesting that differential factor modification, rather than different factors, is involved. As the rGH promoter exhibited a similar pattern of activity in these cell lines, these observations suggest that promoter as well as enhancer elements contribute to the cell specificity of PRL and GH gene expression.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Kallikrein genes: cloning in man and expression in rat renal hypertension.

Genes for the small human glandular kallikrein gene family were isolated. Members of this family include renal/pancreatic kallikrein, prostate-specific antigen and a kallikrein encoded by the first gene that was isolated and completely sequenced, hGK-1. All share strong nucleotide sequence homology, although hGK-1 and the prostate-specific antigen gene are more closely related (86% identity in coding nucleotides). Renal/pancreatic kallikrein has 77% nucleotide homology to prostate-specific antigen, but only 60% amino acid homology. There is strong homology in the 5'-flanking DNA with mouse kallikrein genes, suggesting common regulatory mechanisms. In the rat one-kidney, one clip model of hypertension, renal kallikrein messenger (m)RNA increased during the initial transient rise in plasma renin, and then decreased.

Amino Acid Sequence↗
PubMed1987

Interaction of a tissue-specific factor with an essential rat growth hormone gene promoter element.

Rat growth hormone (rGH) gene expression is normally restricted to the anterior pituitary. As a model of this tissue specificity, we compared the transient expression of an rGH-chloramphenicol acetyltransferase (CAT) hybrid gene in rGH-producing rat pituitary tumor (GC) cells and in non-rGH-producing rat fibroblast (rat-2) cells. Deletion analysis of the rGH portion of this hybrid gene demonstrated that DNA sequences within 140 base pairs 5' to the rGH gene were sufficient for correct cell type-specific expression. Deletion of an additional 35 base pairs of the rGH 5'-flanking DNA resulted in a loss of expression of the transfected hybrid gene and correlated with the interaction of a putative trans-acting factor with this region of the rGH promoter. This factor was detectable by DNase I footprinting in a crude nuclear extract from GC cells but not from rat-2 cells. Site-directed mutagenesis of the footprint region caused complete loss of expression of a hybrid gene containing 530 base pairs 5' to the rGH gene. Thus, the interaction of this factor, which we term GC2, is likely to be essential for the tissue-specific expression of the rGH gene.

Animals↗
PubMed1987

A pituitary-specific factor interacts with an upstream promotor element in the rat growth hormone gene.

The expression of the rat GH (rGH) gene is limited to the anterior pituitary. Using a DNase I footprinting assay, we have sought to identify specific protein-DNA interactions in the rGH 5'-flanking DNA that may be important in conferring tissue-specific use of the rGH promoter. We have identified a nuclear factor from rGH-secreting GC (rat pituitary) cells which interacts in the rGH 5'-flanking DNA between positions -94 to -62 relative to the start site of rGH gene transcription. This factor, which we have named GC1, is undetectable in nuclear extracts of non-rGH-producing rat fibroblast (Rat-2), or HeLa cells. Mutation of the GC1 binding region in the rGH 5'-flanking DNA results in only a small (30%) decrease in the ability of the rGH promoter to drive the expression of a linked marker gene when transfected into GC cells. GC1 represents, therefore, a novel type of promoter binding factor which is gene-specific and whose distribution is tissue-specific, but which is nonessential for the basal expression of its linked gene. Such a factor may, however, play a role in the modulation of rGH gene expression either through its interaction with other regulatory proteins or ligands or after enzyme modification.

Animals↗
PubMed1986

Evolution of renin.

New gene data for three aspartyl proteases (human renin, mouse renin and human pepsin) permitted closer analysis of the gene duplication and fusion hypothesis for the evolution of this family of enzymes. Alignment of sequences in the hemilobes of human pepsin revealed only weak homology in amino acid sequences. Nucleotides were, however, more homologous. Splice junctions between putative duplicated exons did not match. Repeated sequences in the human renin gene were detected by hybridization with total human DNA labelled with 32P. These were not, however, consistent with unequal crossing-over between repeated sequences of an ancestral gene having occurred. The data thus provide no immediate support for the gene duplication and fusion hypothesis. The symmetry in structure of an aspartyl protease may arise from the tendency of hydrophilic amino acids to be encoded at splice junctions. This would divide a molecule comprised mainly of beta-sheets into roughly superimposable domains.

Animals↗
PubMed1986

Human cardiac myosin heavy chain genes. Isolation of a genomic DNA clone and its characterization and of a second unique clone also present in the human genome.

A gene sequence coding for myosin heavy chain (MHC) of human cardiac muscle was isolated by screening a human genomic library with a 32P-labelled 1.1kb SacI restriction fragment from a previously characterized cDNA clone specifying the light meromyosin and 3' untranslated region of mRNA encoding rabbit cardiac alpha-MHC. The DNA of this human genomic clone (lambda HCMHC8) hybridized much more strongly than did other clones isolated under similar, low stringency conditions both to the rabbit cDNA probe and to mRNA isolated from rat cardiac, but not skeletal, muscle tissue. Probe made from a DNA restriction fragment of lambda HCMHC8 hybridized a single 31S band of human ventricular mRNA. This size is identical to that of cardiac MHC mRNA of other species. Heteroduplex analysis showed hybridization of lambda HCMHC8 with exon segments in a rabbit cardiac MHC genomic clone (lambda MHC alpha 12/1). It also showed that lambda HCMHC8 spanned 14 kb of DNA and contained exon segments estimated to code for two-thirds of a MHC including the carboxylic acid terminus. By rescreening the library under more stringent conditions, where only DNA sequences having strong homology to cardiac MHC genes would be expected to hybridize, clones having restriction maps overlapping lambda HCMHC8 were isolated together with a unique clone (lambda HCMHC9). DNA gel blot hybridization of human genomic DNA with lambda HCMHC8 probe at medium stringency gave a pattern of restriction fragments similar to the restriction map of lambda HCMHC8. A weaker set of bands also appeared which corresponded in pattern to the map of lambda HCMHC9.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

Studies of the regulation of mouse renin genes by measurement of renin messenger ribonucleic acid.

The transcriptional activity of renin genes in the mouse kidney and submandibular gland (SMG) was examined by measurement of renin messenger RNA (mRNA) (nanograms per g tissue) and compared with renin activity (micromoles angiotensin I per h/g tissue). In control adult mice renin mRNA and renin activity (in parentheses) were 1.8 +/- 0.24 (11 +/- 1.1) in male kidney, 3.6 +/- 0.66 (18 +/- 2.8) in female kidney, 230 +/- 34 (903 +/- 59) in male SMG, and 31 +/- 6 (188 +/- 47) in female SMG (mean +/- SE, n = 6). The ratio of renin mRNA among these four tissues was similar to that of renin activity (1:2:100:17, respectively). Although the values in male kidney were one one-hundredth those in SMG, 1000 to 10000 times more SMG cells are involved per gram of tissue so that, per renin-synthesizing cell, kidney values would be 10 to 100 times SMG values. Expression of renin gene(s) in a renal juxtaglomerular cell may thus be higher than in a SMG granular duct cell. Values in adult male SMG were a consequence of a 40-fold rise at puberty, were decreased to 16% (+/- 3.8) by castration, but were not significantly influenced by treatment with testosterone, T4, propylthiouracil, sodium depletion, or spironolactone. Renin mRNA in adult female SMG was 18-fold higher than juvenile values, was increased 10-fold (+/- 1.6) by testosterone (to adult male levels) and 5.5-fold (+/- 0.81) by T4 (P less than 0.005), but was decreased to 42% (+/- 29) of normal by propylthiouracil (P less than 0.05). Propylthiouracil caused a small but significant decrease in testosterone-treated female values. In the kidney renin mRNA was increased 3.0-fold (+/- 0.30) by captopril, 2.3-fold (+/- 0.23) by a low sodium diet, and 1.7-fold (+/- 0.13) by spironolactone after 1 week, whereas T4, testosterone, or propylthiouracil had little or no effect. Sialoadenectomy increased renin mRNA and renin in male but not in female kidney, suggesting that a SMG factor, possibly renin, may have a role in suppression of renin synthesis in male kidney. In conclusion, measurement of renin mRNA suggests that testosterone regulates renin gene expression by a direct effect in male mouse SMG, whereas in the female regulation is by thyroid hormone. In the kidney conditions which increase renin content are accompanied by parallel (5-fold higher) increases in renin mRNA, suggesting enhanced expression of renin gene(s) in renal juxtaglomerular cells in chronic low sodium states.

Animals↗
PubMed1984

Primary structure of the human renin gene.

The gene encoding human renin has been isolated on two overlapping clones from a bacteriophage lambda library of human DNA. The entire gene spans about 12,000 bp and contains 10 exons separated by 9 intervening sequences. The gene structure is similar to that of human pepsinogen in terms of overall size, homology in the coding regions, position of introns, and sizes of the exons, suggesting that the two genes are evolutionarily related. However, a novel exon coding for only three amino acids was detected that is not present in the pepsinogen gene and whose amino acids are also not found in mouse renin. Although the nucleotide sequence of the 5'-flanking DNA differs from that of the pepsinogen gene, in both cases this region contains a structure of almost perfect dyad symmetry which immediately precedes the TATA box and may have functional importance. Furthermore, sequences resembling the putative consensus sequence for glucocorticoid regulation of gene expression are located approximately 200 and 300 bp upstream from the gene. The overall structural anatomy suggests that the human renin gene evolved by mechanisms that include a duplication of exon segments, particularly those containing the codons for the catalytically important aspartate residues, together with the insertion of other exon and flanking DNA structures. An analysis of human chromosomal DNA demonstrates that there is only one gene with high homology to human renin.

Base Sequence↗
PubMed1983

The biosynthetic pathway of renin in mouse submandibular gland.

The present study set out to demonstrate the biosynthesis of a prorenin and its processing in the cell, using the richest known natural source of renin, the mouse submandibular gland. Cell-free translation of total poly(A+) RNA or mRNA selected using a renin cDNA yielded Mr = 45,000 preprorenin which in the presence of dog pancreatic microsomal membranes, was converted to Mr = 43,000 prorenin. The latter was seen during in vitro labeling of tissue with [35S]methionine. Prorenin was synthesized first and converted rapidly to Mr = 38,000 single chain renin. Renin was then hydrolyzed slowly to give two chains of Mr = 33,000 and 5,000 held together by disulfide bonds. The Mr = 38,000 and 33,000 species had similar peptide maps. Western blotting of fractions from a pepstatin affinity column identified the separation of prorenin from renin. The results suggested that both single and two-chain renin have an exposed active site. Testosterone stimulated synthesis of prorenin during in vitro labeling of female tissue. Thus, mouse renin is synthesized as a preprorenin (Mr = 45,000) which is converted to a prorenin (Mr = 43,000) and then to renin (Mr = 38,000) by rapid processing within the cell, after which renin is cut slowly to give a two-chain form.

Animals↗
PubMed1983

Detection of renin mRNA in mouse kidney and submandibular gland by hybridization with renin cDNA.

The presence of renin mRNA in a tissue is a manifestation of the expression of the renin gene by that tissue. In the present study 32P-labeled, single-stranded renin complementary DNA was used as a specific probe for the detection of renin mRNA in tissues by hybridization of their complementary base sequences. With use of the technique of hybridization histochemistry, renin cDNA probe bound strongly to sections of submandibular gland from male Quackenbush mice, a tissue which displays high androgen-dependent renin synthesis. Less was present in the female gland. In the kidney the probe localized in the cortex. A dot hybridization assay was developed to measure renin mRNA in serially diluted total RNA spotted onto nitrocellulose filters along with renin cDNA standards. From the concentration the ratio of renin mRNA between male and female submandibular gland and kidney was calculated as approx. 100:8:1:1, respectively, which is similar to the relative proportion of renin concentrations between these tissues. The present study thus provides the basis for investigations of the expression of the renin gene by tissues, particularly those with high renin biosynthetic activity.

Animals↗
PubMed1982

Mouse glandular kallikrein genes. Nucleotide sequence of cloned cDNA coding for a member of the kallikrein arginyl esteropeptidase group of serine proteases.

A library of cloned cDNA to male mouse submaxillary gland poly(A)-containing RNA was constructed in the plasmid pBR322. Inserts containing sequences estimated to be in the 1-5% abundance class were identified by hybridization to radiolabeled cDNA and examined by nucleotide sequence analysis. A sequence coding for a peptide with 57% homology to the only complete kallikrein sequence reported to date (from pig pancreas) was identified by a computer search program. This insert appears to code for the COOH-terminal 149 amino acids of a protein presumed therefore to be a serine protease. Comparison of the predicted amino acid sequence of this protein with analogous sequences in the three characterized members of the mouse submaxillary gland kallikrein arginyl esteropeptidase group of enzymes revealed extensive homology, although not complete identity. Thus, there are at least four members of this enzyme family expressed in the mouse submaxillary gland.

Amino Acid Sequence↗
PubMed1982

Biosynthesis of preprorenin. Studies using whole tissue, a cell-free system, and E. coli containing cDNA inserted at the PstI site of plasmid pBR322.

The biosynthesis of renin as a higher molecular weight 'prorenin' was demonstrated by in vitro incorporation of [35S] methionine into nascent polypeptides of submandibular gland tissue from adult male mice. Immunoprecipitation with anti-renin and electrophoresis identified a Mr 44,500, pI 6.4 prorenin which normally represented 5% of renin-immunoreactive protein in tissue extracts and which was rapidly converted during in vitro labeling into a Mr 40,000, pI 6.2 species. The latter was subsequently processed slowly to forms of Mr 35,500, pI 5.6 and Mr 34,000, pI 5.4. The influence of processing enzymes was then eliminated by synthesizing renin in a cell-free translation system containing rabbit reticulocyte lysate and mRNA isolated from submandibular glands. This yielded an even larger species of Mr 46,000 likely to be 'preprorenin'. A clone bank of mouse submandibular gland cDNA was prepared. This consisted of E. coli RRI transformed with plasmid pBR322 in which cDNA had been inserted at the PstI site so that the bacteria could express the encoded polypeptide. Renin-immunoreactive colonies were identified suggesting the expression of renin-like proteins by a prokaryote. The cDNA which was 700-1000 base pairs big was excised for sequencing.

Animals↗
PubMed1982

Renin synthesis and gene cloning.

1. The present study describes the biosynthesis and gene cloning of mouse submandibular gland renin. 2. After translation of mRNA coding for renin a Mr 46 000 protein is produced (preprorenin). However, rapid removal of the 'pre' segment from the nascent chain would account for the fact that in pulse-chase and continuous labelling experiments the largest renin-immunoreactive protein seen was of Mr 44 500, pI 6.4 (determined by 2-dimensional gel electrophoresis). This 'prorenin' was rapidly converted to a Mr 40 000, pI 6.2 species and then more slowly to forms of Mr 35 500, pI 5.6 and Mr 34 000, pI 5.4, which correspond in Mr and pI to renin isolated in pure form from mouse submandibular glands. 3. Colonies of the bacterium Escherichia coli strain RRI, containing plasmid pBR322 into which mouse submandibular gland cDNA had been inserted at the PstI site, were screened with affinity-purified anti-renin. Of 500 colonies, two were found that reacted positively with the antibody. These contained protein that could be immunoprecipitated with anti-renin and cDNA which was capable of inter-colony hybridization and which had a HinfI restriction site in each case.

Animals↗
PubMed1981

Evidence that the arginine esteropeptidase (gamma) subunit of nerve growth factor can activate inactive renin.

The beta and gamma subunits of nerve growth factor were isolated and tested for inactive-renin-activating activity using human amniotic fluid as a convenient source of inactive renin. Only the gamma subunit, which is an arginine esteropeptidase, could activate inactive renin. The role of this enzyme in sites containing both it and inactive renin warrants investigation.

Amniotic Fluid↗
PubMed1981

Kallikrein and renin: molecular biology and biosynthesis.

1. A cDNA clone library was constructed from male mouse submandibular gland poly(A)+RNA. 2. A 500 base-pair sequence consisting of a 3' untranslated region plus a 447 base-pair region coding for an amino acid sequence having 57% homology with the C-terminal 149 amino acids in the 230 amino acid chain of porcine pancreatic kallikrein was identified. 3. The sequence was strongly but not completely homologous with known mouse submandibular gland serine proteinase sequences and represents the first report of a DNA base sequence for a serine proteinase. It may be part of the gene coding for kallikrein. 4. The biosynthetic pathway for renin was established by continuous-labelling, pulse-chase and cell-free translation studies of submandibular gland tissue from normal and testosterone-induced mice. 5. Renin was synthesized as a mol. wt. 46000 preprorenin which is likely to be hydrolysed before completion of the nascent chain. A prorenin of mol. wt. 44500, pI 6.4 was identified and shown to be rapidly converted into a mol. wt. 40000, pI 6.2 renin, which was then converted more slowly into forms of mol. wt 35500, pI 5.6 and mol. wt. 34000, pI 5.4.

Amino Acid Sequence↗
PubMedDate not supplied

Activation of plasma prekallikrein and inactive renin by puff adder venom.

The activation of inactive renin during incubation of human plasma with puff adder venom at pH 7.4 was found to be a complex process. Gel filtration on Sephacryl S-200 indicated that the venom contains a major peak of caseinolytic and renin-activating activity of low molecular weight. This enzyme was a metalloproteinase. During incubation with plasma the metalloproteinase formed a complex with alpha 2-macroglobulin and retained caseinolytic and reninactivation activity. Venom metalloproteinase activated prekallikrein, but not plasmin, and plasms kallikrein may account for at least part of the activation of inactive renin observed.

Caseins↗