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31.
Nadine B. Carozzi Gregory W. Warren Nalini Desai Susan M. Jayne Richard Lotstein Douglas A. Rice Stephen Evola Michael G. Koziel 《Plant molecular biology》1992,20(3):539-548
Insecticidal transgenic tobacco plants containing a truncated Bacillus thuringiensis cryIA(b) crystal protein (ICP) gene expressed from the CaMV 35S promoter were analyzed for ICP gene expression under field and greenhouse conditions over the course of a growing season. We present new information on temporal and tissue-specific expression of a CaMV 35S/cryIA(b) gene. Levels of cryIA(b) protein and mRNA were compared in both homozygous and hemizygous lines throughout plant development. Levels of ICP mRNA and protein increased during plant development with a pronounced rise in expression at the time of flowering. Homozygous ICP lines produced higher levels of ICP than the corresponding hemizygous lines. ELISA analysis of different tissues in the tobacco plant showed ICP gene expression in most tissues with a predominance of ICP in older tissue. All transgenic ICP tobacco lines which were studied in the field and greenhouse contained 400 ng to 1 g ICP per gram fresh weight in leaves from the mid-section of the plant at flowering. The amounts of ICP produced by field lines were directly comparable to levels observed in greenhouse-grown plants. 相似文献
32.
Arvind K. Virmani Bashoo Naziruddin Vinay C. Desai Jon P. Lowry Donald C. Graves Goverdhan P. Sachdev 《In vitro cellular & developmental biology. Animal》1992,28(2):120-127
Summary The purpose of this investigation was to provide evidence for the secretion of high molecular weight mucins, CTM-A and CTM-B,
in primary culture of canine tracheal epithelial (CTE) cells. The cells were isolated from tracheas of mongrel dogs by pronase
treatment. Primary cultures of the epithelial cells were established using ICN cellagen inserts in Dulbecco’s modified Eagle’s/F12
medium supplemented with growth factors and could be maintained for up to 23 days. The evidence for the mucin secretion in
culture medium and their localization in the cells was established by a) positive immunocytochemical staining using specific
antibodies developed against purified native as well as deglycosylated CTM-A and CTM-B; b) incorporation of labeled amino
acids, followed by electrophoresis and autoradiography detection of glycoconjugates purified from the culture medium; c) comparison
of the amino acid compositions of mucin purified from canine tracheal pouch secretions and that purified from the culture
medium; and d) Western blot analyses using specific polyclonal antibodies directed against deglycosylated CTM-A and CTM-B.
Immunoaffinity purified secreted labeled glycoconjugates were resistant to hyaluronidase treatment. The effects of cyclic
AMP (1 × 10−5
M), dibutyryl cyclic AMP (1 × 10−5
M), 8-bromocyclic AMP (1 × 10−5
M), and prostaglandin E1 (1 × 10−6
M) on mucin secretion by CTE cells were also investigated. Secretion of mucins by CTE cells in culture was considerably more
enhanced by 8-bromocyclic AMP than that observed for other secretagogues used in this study. 相似文献
33.
Triacylglycerol breakdown (lipolysis) results from a series of reactions culminated by activation of "hormone-stimulated" triacylglycerol lipase, an enzyme unique to adipose tissue. We have studied various components of the lipolytic process in human omental adipocyte precursors differentiating in culture. The levels of cyclic AMP, the "second messenger" of lipolytic hormones, were about sixfold higher in fat cell precursors than those in abdominal skin fibroblasts. L-Isoproterenol resulted in significant elevation of cyclic AMP levels in both cell types. Preincubation of intact adipocyte precursors with insulin resulted in significant enhancement of "low Km" cyclic AMP phosphodiesterase activity; in contrast, this hormone had no effect on fibroblast phosphodiesterase activity, a distinctive biochemical difference despite the morphological similarities between the two cell types during the early stages of adipocyte precursor maturation. Incubation of adipocyte precursors with isoproterenol resulted in the release of fatty acids into the medium, findings indicative of "hormone-stimulated" lipase activity and, hence, the operation of the entire "lipolytic cascade"; isoproterenol-stimulated lipolysis was inhibited by insulin. Release of fatty acids from fibroblasts was not observed. Thus, "hormone-stimulated" lipolysis and insulin stimulation of cyclic AMP phosphodiesterase activity are expressed during early stages of human adipocyte precursor differentiation. 相似文献
34.
Purification of the glycoprotein lectin from the broad bean (Vicia faba) and a comparison of its properties with lectins of similar specificity. 总被引:10,自引:7,他引:3 下载免费PDF全文
1. The lectin from the broad bean (Vicia faba) was purified by affinity chromatography by using 3-O-methylglucosamine covalently attached through the amino group to CH-Sepharose (an omega-hexanoic acid derivative of agarose). Its composition and the nature of its subunits were compared with concanavalin A and the lectins from pea and lentil. 2. Unlike the other three lectins, broad-bean lectin is a glycoprotein; a glycopeptide containing glucosamine and mannose was isolated from a proteolytic digest. 3. The mol.wt. is about 47500; the glycoprotein consists of two apprently identical subunits, held together by non-covalent forces. Fragments of the subunits, similar to those found in concanavalin A and soya-bean agglutinin, were found in active preparations. 4. Broad-bean lectin was compared with concanavalin A and the lectins from pea and lentil in an investigation of the inhibition of their action by a number of monosaccharides, methyl ethers of monosaccharides, disaccharides and glycopeptides. The most striking differences concern 3-O-substituted monosaccharides, which are strong inhibitors of the action of broad-bean, pea and lentil lectins but not of the action of concanavalin A. There is, however, no strong inhibition of the action of these lectins by 3-Olinked disaccharides. 相似文献
35.
A longitudinal study of the mental and physical development of 200 children with normal haemoglobin and 21 with the sickle-cell trait was carried out in a small rural community in Jamaica. At about 2 and 10 years of age heights and weights showed no significant differences. At about 10 years of age classroom behaviour, sociability, and educational achievement were similar. The results suggest that the sickle-cell trait does not affect growth and mental development. 相似文献
36.
Summary It has been attempted to isolate and characterize the folate precursors in the culture filtrates of two folate-requiring organisms, Streptococcus faecalis R and Lactobacillus casei. On the basis of paper chromatography, bioautography, ultra violet absorption spectra, chemical reactions, and differential microbiological responses it has been concluded that L. casei cultures contain a compound similar to pteroic acid which can be utilized by S. faecalis R. The S. faecalis R cultures on the other hand appear to accumulate a pteridine derivative active for Crithidia fasciculata It has been confirmed that this pteridine is not derived from the folic acid usually added to the growth medium.Abbreviations PGA
Pterolyglutamic acid
- PABA
p-aminobenzoic acid 相似文献
37.
Summary Polyethylene glycol 6000 mediated protoplast fusion between an alkane degrader Acinetobacter sp. A3, and a naphthalene degrader, Pseudomonas putida DP99 , resulted in fusants capable of degrading both hydrocarbons and were morphologically similar to Acinetobacter sp. A3. While fusant F4/13 and Pseudomonas putida DP99 degraded over 98% of naphthalene provided by the end of five days, tetradecane degradation by fusant F4/13 was 82% compared to 77% by Acinetobacter sp. A3 in the same time period. Also, while from naphthalene +tetradecane mixture, fusant F4/13 could degrade 99% and 53% of naphthalene and tetradecane respectively, both the parent strains together could degrade over 99% naphthalene but only about 16% tetradecane. 相似文献
38.
Desai Chirag S. Khan Aisha Bellio Michael A. Willis Micah L. Mahung Cressida Ma Xiaobo Baldwin Xavier Williams Brittney M. Baron Todd H. Coleman Leon G. Wallet Shannon M. Maile Robert 《Molecular and cellular biochemistry》2021,476(12):4331-4341
Molecular and Cellular Biochemistry - Plasma-derived extracellular vesicles (EV) can serve as markers of cell damage/disease but can also have therapeutic utility depending on the nature of their... 相似文献
39.
Franz Meitinger Dong Kong Midori Ohta Arshad Desai Karen Oegema Jadranka Loncarek 《The Journal of cell biology》2021,220(7)
Centrosomes are composed of a centriolar core surrounded by pericentriolar material that nucleates microtubules. The ubiquitin ligase TRIM37 localizes to centrosomes, but its centrosomal roles are not yet defined. We show that TRIM37 does not control centriole duplication, structure, or the ability of centrioles to form cilia but instead prevents assembly of an ectopic centrobin-scaffolded structured condensate that forms by budding off of centrosomes. In ∼25% of TRIM37-deficient cells, the condensate organizes an ectopic spindle pole, recruiting other centrosomal proteins and acquiring microtubule nucleation capacity during mitotic entry. Ectopic spindle pole–associated transient multipolarity and multipolar segregation in TRIM37-deficient cells are suppressed by removing centrobin, which interacts with and is ubiquitinated by TRIM37. Thus, TRIM37 ensures accurate chromosome segregation by preventing the formation of centrobin-scaffolded condensates that organize ectopic spindle poles. Mutations in TRIM37 cause the disorder mulibrey nanism, and patient-derived cells harbor centrobin condensate-organized ectopic poles, leading us to propose that chromosome missegregation is a pathological mechanism in this disorder. 相似文献
40.
Patil Saurabh Gupta Kritika Pandit Ashish Desai Bhushan Gschliesser Siegfried Dandekar Prajakta Jain Ratnesh 《International journal of peptide research and therapeutics》2021,27(4):2831-2844
International Journal of Peptide Research and Therapeutics - The development of peptide-based formulations presents numerous challenges to the formulator due to their complexity, delicate structure... 相似文献