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D M Carlson

Publications and source records attributed to D M Carlson.

At least 37 records · Page 2Linked to original sources

An unusual expression of a squamous cell marker, small proline-rich protein gene, in tracheobronchial epithelium: differential regulation and gene mapping.

An unusual expression of a putative squamous cell marker, small proline-rich protein (spr1), in mucociliary epithelial cells of conducting airways was demonstrated in a serum-free culture system. A cDNA clone was isolated from the cDNA library of monkey tracheobronchial epithelial (TBE) cells by differential hybridization. This cDNA clone, MT5, exhibited 98% homology to a DNA sequence obtained from human keratinocytes treated with either UV light or phorbol esters (T. Kartasova et al., 1988, Mol. Cell. Biol. 8:2195-2230). The predicted peptide of MT5 is unusual for its high content of proline (29%), glutamine (18%), and cysteine (9%) and its repeated PKVPEPC units. The level of spr1 mRNA in cultured cells was inhibited more than 90% by vitamin A. In contrast, phorbol 12-myristate 13-acetate (PMA) stimulated the level of spr1 mRNA by 3- to 8-fold. This differential regulation coincided with the effects of these chemicals on the cornification of cultured TBE cells. Using MT5 as a probe, we have localized the tracheal spr1 gene on the human chromosome 1 by a Southern blot analysis using a panel of human-rodent somatic cell hybrid DNAs. The gene was further sublocalized to bands q22-23 by in situ hybridization.

Amino Acid Sequence↗

Identification and preliminary characterization of white sturgeon (Acipenser transmontanus) vitellogenin mRNA.

Vitellogenesis was induced in white sturgeon by administration of estrogen through silastic implants. Vitellogenin mRNA was identified by agarose gel electrophoresis and cell-free translation. A highly abundant 5.7-kb mRNA was induced in the liver of estrogen-treated sturgeon. Cell-free translation of poly(A)+ mRNA showed the induction of two high-molecular-weight proteins of 180 and 120 kDa. These two proteins, encoded by the 5.7-kb mRNA(s), were immunoprecipitated by antiserum to serum from vitellogenic sturgeon. Immunoprecipitations also showed the presence of four other serum proteins synthesized by the liver of estrogen-treated sturgeon. The induction of vitellogenesis by estrogen in sturgeon, which are a primitive teleost, was found to be similar to induction of vitellogenesis in amphibians, avians, and other teleosts. Estrogen treatment induced a highly abundant vitellogenin mRNA as well as several mRNAs for other serum proteins. However, the presence of two distinct vitellogenin monomers in the cell-free translation assay was significantly different from the results in other species.

Animals↗

Glycoproteins: carbohydrates to cloning.

This article is dedicated to Professor Saul Roseman and briefly outlines some of the early studies on sialyltransferases, on glycoproteins such as pig submaxillary mucins and, more recently, on a series of unusual proteins and glycoproteins high in proline, the so-called proline-rich proteins. Hopefully, it represents, in an inadequate manner, my appreciation for 'The man and his works'. During the Roseman Symposium at the 11th International Symposium on Glycoconjugates in Toronto, several of his former students and postdocs tried to describe what it was like in the Roseman laboratory. Clearly, the time I was in Saul's lab was like no other time in my career. Thanks for everything, Saul.

Amino Acid Sequence↗

Ocular ochronosis from alkaptonuria.

Alkaptonuria is an extremely rare, autosomal recessive disorder in which the metabolic enzyme homogentisic acid oxidase is deficient. A common sequelae is the subsequent accumulation of homogentisic acid in collagenous tissues, such as the sclera, nose and ear lobes. The blue-black pigmentation found in patients with alkaptonuria is called ochronosis. Another ocular sign includes amber-colored oil globulation within Bowmans membrane of the cornea.

Aged↗

Induction in the expression of an unusual proline-rich protein by pig tracheal surface epithelial cells maintained in primary culture.

Primary cell culture is a valuable tool for studying the regulation of gene expression since many differentiated traits are conserved. Cells cultured from the epithelial lining of pig trachea were selected as a model system for mucin synthesis. RNAs were isolated from pig trachea epithelial linings and from pig trachea surface epithelial cells cultured in serum-free media. Cell free translations showed an unusually high incorporation of [3H]proline into a relatively small protein (about 20 kDa), but only with RNA from the cells in culture. RNA prepared from pig trachea cells immediately before placing the cells in culture (day 0) did not contain mRNA encoding this unusual proline-rich protein. However, the expression of this protein was dramatically induced within 2 days of maintaining the cells in culture.

Animals↗

Regulation of proline-rich protein gene expression by cyclic AMP in primary cultures of hamster parotid glands.

Proline-rich proteins (PRPs) constitute a group of unusual salivary proteins encoded by tissue-specific multigene families which can be dramatically induced (20- to 70-fold) in vivo in rats, mice and hamsters by treatment with the beta-agonist isoproterenol. Addition of dibutyryl cyclic AMP (dbcAMP) or forskolin to hamster parotid gland primary cultures resulted in a large increase (15- to 30-fold) in PRP mRNA levels. The same time-course and levels of induction of PRP mRNA by dbcAMP and isoproterenol were found in primary cultures, indicating that both effectors act through the same mechanism. Induction by isoproterenol, but not by dbcAMP or forskolin, was blocked by the beta-antagonist propranolol. Incorporation of [3H]proline into PRPs was stimulated in primary cultures by all three effectors. The greatest increase in proline incorporation was in the [3H]PRPs recovered in the culture medium of induced cells. These studies demonstrate that cAMP or agents which increase intracellular cAMP levels increase PRP gene expression in primary cultures of parotid glands. Pretreatment of the cells with cycloheximide blocked the induction of PRP mRNAs which indicates that the synthesis of a trans-acting factor may be necessary for transcriptional activation of the PRP genes. alpha-Amylase mRNA, another tissue-specific gene product, was not significantly affected by cycloheximide treatment.

Animals↗

An ELISA method for the quantitation of tracheal mucins from human and nonhuman primates.

Monoclonal antibodies, 17B1 and 17Q2, which are specific for large molecular weight mucous glycoproteins of airway epithelium, have been used to develop an ELISA method to quantitate the tracheal mucins of humans and rhesus monkeys. The assay is a double-sandwich system that does not depend on either the binding of mucous antigens to the microtiter plate or the use of a second antibody. The assay protocol includes (1) coating the microtiter well with purified IgG of 17B1 or 17Q2, (2) incubating the wells with mucous samples, (3) binding of alkaline phosphatase-conjugated IgG to the wells, and (4) developing the color with phosphate substrate. This ELISA method is very sensitive for human and rhesus monkey tracheal mucins. Quantitation is not affected by the presence of various proteoglycans (keratan sulfate, hyaluronate, heparin, heparan sulfate, and chondroitin sulfate). However, the quantitation is affected by the treatment of antigen with periodic acid and endo-beta-galactosidase. Other enzymes (e.g., neuraminidase, hyaluronidase, chondroitinase, heparitinase, heparinase, fucosidase, keratanase) have no effect on the antigenicity of substrate. The quantitation is linear, with a concentration from 0.2 to 4 ng protein/sample. The ELISA method developed in this study should be useful for quantitating the mucin content of various biologic fluids, such as sputum, bronchoalveolar lavage, and media from cultures following various pharmacologic and physiologic manipulations.

Amino Acids↗

Molecular evolution of the mouse proline-rich protein multigene family. Insertion of a long interspersed repeated DNA element.

Proline-rich proteins (PRPs) in the salivary glands of mice, rats, and hamsters are encoded by tissue-specific inducible multigene families. Mouse PRP genes are located on chromosome 8, and transcription is dramatically induced (about 70-fold) by isoproterenol treatment. Clones containing two nonallelic PRP genes (MP2 and M14) were isolated from cosmid and phage libraries of CD-1 mouse genomic DNA. The cloned regions comprise a contiguous block of 77 kilobase pairs of the mouse genome. Restriction mapping established the physical lineage of PRP genes MP2 and M14, and they are tandemly arrayed. The DNA sequence analysis presented in this report suggests that genes M14 and MP2 (Ann, D. K., and Carlson, D. M. (1985) J. Biol. Chem. 260, 15863-15872) arose via a gene duplication of a common ancestor. Two major differences between M14 and MP2 were observed. PRP gene MP2 has 13 tandemly arrayed 42-nucleotide repeats in exon II, whereas M14 has 17 repeats, and PRP gene M14 has an insertion by transposition of a 2-kilobase pair member of the long interspersed repeated DNA (LINE) family (LIMd) into intron I. The evolution of this PRP multigene family has been dominated by intra-exonic amplification of repeating nucleotide units coding for these and other proline-rich repeated peptides and by gene duplication. The LIMd element gives rise to heterogenous EcoRI, BamHI, and HindIII restriction enzyme patterns, and this insertion is also present in BALB/c, C57BL/6J, and DBA/2J mice.

Amino Acid Sequence↗

Retinol-regulated gene expression in human tracheobronchial epithelial cells. Enhanced expression of elongation factor EF-1 alpha.

Conducting airway epithelial cells requires vitamin A or its synthetic chemicals (retinoids) for their survival and for the expression of normal mucociliary functions. By using molecular cloning, we have shown that one of the effects of retinol on cultured human tracheobronchial epithelial (HTBE) cells is the enhancement (from 2- to 4-fold) of the mRNA encoding the elongation factor EF-1 alpha. Sequence analysis has shown that clone HT7, which was identified by differential hybridization procedures, contained a cDNA insert which encoded a protein closely resembling (81%) elongation factor EF-1 alpha from brine shrimp and completely identical to the published sequence of human elongation factor EF-1 alpha (Brands, H.H.G.M., Maassen, J.A., Van Hemert, F.J., Amons, R., and Moller, W. (1986) Eur. J. Biochem. 155, 167-171). Regions of homology of HT7 to EF-Tu from yeast mitochondria, plant chloroplasts, and Escherichia coli are also evident. A single RNA band at 1700 bases was observed for both untreated and retinol-treated HTBE cells, and for mouse liver and parotid glands when Northern transfer from denaturing agarose gel was probed with a 32P-labeled HT7 insert. An enhanced amino acid incorporation and increased protein content per cell for HTBE cells grown in the presence of retinol were observed. Results presented by these studies indicate that retinol may regulate the transcription of a factor required for translation.

Amino Acid Sequence↗

Proline-rich proteins and glycoproteins: expression of salivary gland multigene families.

Our recent research interests have focused on a group of unusual proteins and glycoproteins high in proline content, or the so-called proline-rich proteins (PRPs). The PRPs are tissue-specific expressions of salivary gland multigene families. Normally PRPs are not detected or are present in very low amounts in rat, mouse and hamster salivary glands, but these unusual proteins are dramatically induced by treatment with the catecholamine isoproterenol. The structures and organizations of several PRP mRNAs and PRP genes have been determined. The amino acid sequences of all PRPs show 4 distinct regions, namely, a signal peptide, a transition region, a repeat region and a carboxyl-terminal region. Glycoproteins induced by isoproterenol treatment may be N-glycosylated or O-glycosylated. The N-glycosylated glycoprotein GP-158 from rat submandibular glands has a 12 amino acid glycopeptide which repeats possibly 49 times. Proline-rich proteins of the parotid glands of rats and mice are also greatly induced by dietary tannins. The apparent unique occurrence of PRPs in saliva suggests that one biological role is to neutralize the detrimental effects of dietary tannins and other polyphenols. The upstream regions of the mouse and hamster PRP genes contain cyclic AMP-regulated sequences as demonstrated by deletions and transient transfections. The PRP multigene family members of mouse are all located on chromosome 8.

Amino Acid Sequence↗

The preparation of poly(A)+mRNA from the hagfish slime gland.

The isolation of translatable poly(A)+mRNA from the slime glands of the Pacific hagfish, Eptatretus stouti, is not possible by the commonly used procedures because of the viscous slime that is formed when the contents of the glands are hydrated. This paper reports on a procedure developed to overcome this problem. Briefly, the tissue was powdered in liquid nitrogen, mixed with sodium lauroylsarcosine and proteinase K and lyophilized. The lyophilized powder was then mixed with 0.3 mm diameter glass beads, thoroughly ground and wetted with buffer and digested at 37 degrees C. The RNA from the digest was recovered by ultracentrifugation through a CsCl cushion. Further purification of the RNA was accomplished by the usual methods with slight modifications.

Animals↗

Regulation of proline-rich protein and alpha-amylase genes in parotid-hepatoma hybrid cells.

Salivary proline-rich proteins are encoded by tissue-specific multigene families, and are dramatically induced in mice, rats, and hamsters by treatment with the beta agonist isoproterenol. Salivary gland cells, however, are difficult to maintain in a differentiated state in culture and can be induced to synthesize proline-rich protein mRNAs for only a few days. In an attempt to establish a cell line in which it would be possible to regulate proline-rich protein gene transcription, rat parotid gland cells were fused with the rat hepatoma cell line, FTO-2B. Fused cells were obtained that had a frequency of 7.5 x 10(-6), which is about 125-fold greater than the reversion rate of FTO-2B. The hybrid cells exhibited induced proline-rich protein mRNA synthesis when incubated with either dibutyryl cyclic AMP or forskolin. The ability to induce these genes was maintained for at least 20 passages. Most of the fused cell populations also synthesized elevated levels of alpha-amylase mRNA, another tissue-specific gene.

Animals↗

Characterization of primary translation products from ovine and rat salivary gland mRNAs.

Ovine and rat salivary gland mRNAs have been prepared and their translation products characterized. A 60 kD translation product from ovine submaxillary and sublingual gland mRNAs is identical in mass to the ovine apomucin. Two additional ovine translation products, 25 and 40 kD, are specific to mucin-producing salivary glands. Four rat mRNA translation products are encoded by mucin-producing salivary glands (38, 44, 67, 69 kD). These polypeptides were not detected in the parotid gland mRNAs, a serous gland. Each of these products has a high level of [3H]serine incorporation, a characteristic of mucins. The nature of these products suggests that they are mucins or mucin-like and that their molecular weights should approximate that of the corresponding apomucins.

Animals↗

Induction of proline-rich proteins in hamster salivary glands by isoproterenol treatment and an unusual growth inhibition by tannins.

Treatment of hamsters with the beta-agonist isoproterenol caused a dramatic increase in a series of unusual proteins in the parotid and submandibular glands. These proteins are acid soluble and they contain high amounts (mol%) of glutamate plus glutamine (30-35), proline (23-30), and glycine (12-25). Three proteins (HP45, HP43a, and HP43b) were isolated from trichloroacetic acid extracts of parotid glands of isoproterenol-treated hamsters. The basic protein (HP45) was not retained by DEAE-cellulose and did not contain phosphate or carbohydrate. Two acidic proteins (HP43a and HP43b) had the same apparent molecular weight on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, but these were separated by DEAE-cellulose chromatography. HP43a and HP43b contained 4.3 and 5.7 phosphate residues/mol of protein, respectively. Levels of mRNAs encoding this series of proteins showed striking increases following isoproterenol treatment as determined by cell-free translations and Northern analysis. Feeding tannins to rats and mice mimicks the effects of isoproterenol treatment on the parotid gland (Mehansho, H., Hagerman, A., Clements, S., Butler, L., Rogler, J., and Carlson, D.M. (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 3948-3952; Mehansho, H., Clements, S., Sheares, B. T., Smith, S., and Carlson, D. M. (1985) J. Biol. Chem. 260, 4418-4423]. However, hamsters on a high tannin diet (2%) did not respond like rats and mice and instead displayed an unusual growth inhibition. Weanling hamsters maintained on a 2% tannin diet initially lost weight for 3 days and then failed to gain weight for up to 6 months when kept on this diet. Essentially a normal growth rate was observed when the tannin-fed hamsters were switched to a normal diet.

Adenylyl Cyclases↗

Structure, organization, and regulation of a hamster proline-rich protein gene. A multigene family.

Genomic DNA fragments bearing proline-rich protein (PRP) genes expressed specifically in hamster parotid glands have been isolated and characterized. Complete exonic sequences as well as intronic and a considerable portion of the flanking sequences are reported for a PRP gene, H29. H29 is interrupted by three intervening sequences, with consensus splice junctions, and it likely encodes the acidic hamster PRP Hp43a. Exceedingly high homology of the 5'-untranslated region and the sequence encoding the signal peptide is observed with other PRPs of all species studied. Significant homology was also detected among the repetitive sequences of the mature acidic PRPs from human, mouse, hamster, and rat. This conservation of the internal repeats of the PRPs suggested that proline-rich protein gene evolution involved intragenic duplication of internal repeats and gene duplication and conversion. Both hamster and mouse PRP genes (H29 and mouse proline-rich protein gene, respectively) share considerable sequence similarity in the 5'-flanking regions for about 100 base pairs upstream. The remainder of the upstream sequences were heterologous except for three oligonucleotide regions with 60-70% sequence conservation. These three regions are thought to be involved in the regulation of the tissue-specific PRP gene induction.

Amino Acids↗

Induction of tissue-specific proline-rich protein multigene families in rat and mouse parotid glands by isoproterenol. Unusual strain differences of proline-rich protein mRNAs.

A dramatic induction of proline-rich protein mRNAs by the beta-agonist isoproterenol in the parotid and submandibular glands of both rats and mice has been demonstrated using Northern and dot-blot hybridizations and cell-free translation. Proline-rich protein mRNAs were either very low or not detectable in glands of control rats and mice. After 4 days of isoproterenol treatment, mRNAs encoding these unusual proteins comprised over 50% of the total glandular mRNAs. A 2-4-fold increase in proline-rich protein mRNAs was observed in rat parotid glands as soon as 4 h after treatment. The rat proline-rich protein multigene family encodes two groups of mRNAs with sizes ranging from 600 to 1100 bases. Cell-free translations gave about 10-12 proline-rich proteins. In glands of isoproterenol-treated mice, major species of proline-rich protein mRNAs were observed at 1050 and 1300 bases for BALB/cJ and DBA/2J mice and at 1100 and 1200 bases for CD-1 and C57BL/6J mice. Cell-free translations showed unusual differences in proteins synthesized from the four strains after isoproterenol treatment. AtT20 cells were transfected with a mouse proline-rich protein gene inserted into the plasmid pUC8 (pUMP2-BE). Transcription of proline-rich protein mRNA was induced by exposing these transfected cells to either isoproterenol or cAMP, plus theophylline.

Animals↗

Functional status of patients with end-stage renal disease.

A longitudinal study of 979 patients with end-stage renal disease from 27 dialysis centers in the Upper Midwest was conducted to measure the patients' functional status with use of the Karnofsky Activity Scale. At the initiation of dialysis, 50% of all patients were rehabilitated or caring for themselves, and the three variables that most influenced the initial rehabilitation score were age, diabetic status, and sex. Initial functional status was also analyzed for three cohorts of dialysis patients, grouped according to outcome (renal transplantation, continued dialysis, and death). Patients who received a renal transplant had initial rehabilitation scores that were higher than those who underwent dialysis for 2 years or those who died. In the group of patients who underwent dialysis for 2 years, a statistically significant improvement in rehabilitation scores was noted at 2 years in comparison with the scores obtained at the initiation of dialysis. Initial rehabilitation scores were good predictors of the 2-year scores. Of the patients in the 2-year dialysis cohort, 78% maintained or had improvement in their functional status.

Adult↗