Transient expression of foreign genes in tissues of Arabidopsis thaliana by bombardment-mediated transformation.
Explore the source record for details and available documents.
SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
A human apolipoprotein AI (apo AI) minigene and two mutants were cloned into the vector pUHD10-1 for expression studies in COS cells under the control of the strong CMV (cytomegalovirus) enhancer and the own apo AI promoter. In the mutated apo AI minigene (mutant M1) the positions of the triplets of Gln(-2)-Gln-1 at the C-terminus of the prosequence were exchanged against Gln(-8)-Ala-7, the recognition site of the signal peptidase of the wild type human apo AI. The prosequence has been deleted in mutant M2 and the presequence linked directly to the N-terminus of the mature apo AI form. We report here on expression studies in COS cells, a cell line, which does not express apo AI. They were transfected by electroporation with pUHD10-1 constructs, which contain a) the wild type apo AI minigene and b) the two mutant apo AI minigenes with mutations described above. The following results were obtained: a) the wild type and mutant apo AI constructs were efficiently transcribed and translated in COS cells, b) the expression of the wild type preproapo AI minigene in COS cells led to the secretion of proapo AI (29 kDa), that of the mutant (M2) gene, devoid of the prosequence of mature apo AI (28.4 kDa), whereas the product of mutant gene M1 (31 kDa) with the recognition site of the signal peptides transposed to the C-terminus of the prosequence remained uncleaved within the COS cells.(ABSTRACT TRUNCATED AT 250 WORDS)
Using reverse transcription-polymerase chain reaction and in situ hybridization, the expression of the prolactin (PRL) gene was determined during development in gilthead sea bream (Sparus aurata) for the first time. The mRNA for PRL was detected from the second day of the larval stage onwards. This transcript was also located in the adenohypophysial cells, starting at four days post-hatching and was found to be pituitary-specific. Moreover, the possible involvement of PRL in asynchronous growth in the cultivation of gilthead sea bream was also examined. No differences in the distribution of PRL cells were observed in the three sizes of juvenile gilthead sea bream studied. These results suggest that the transcription of PRL is involved in the early development stages of sea bream and that the asynchronous growth-related changes are not due to distinct distribution of PRL cells.
The expression of heat shock protein (Hsp) 25 during odontogenesis in the dental pulp and enamel organ of rat incisors was investigated by immunocytochemistry and confocal microscopy. In the process of dentin formation, immature odontoblasts first exhibited Hsp 25-immunoreactivity, and increased in immunointensity with the advance of their differentiation. In the dental pulp, in contrast, intense immunoreaction in the mesenchymal cells became weak or negative in parallel with the progress of cell differentiation. The immunoreaction for Hsp 25 in the enamel organ revealed a characteristic stage-related alteration during amelogenesis. In secretory ameloblasts, the immunoreaction for Hsp 25 was found throughout their cell bodies, intense reactivity being located near the proximal and distal terminal webs. At the maturation stage, ruffle-ended ameloblasts (RA) consistently showed Hsp 25-immunoreactivity throughout the cell bodies, whereas smooth-ended ameloblasts (SA) lacking a ruffled border were weak in immunoreaction at the distal cytoplasm. Other cellular elements of the enamel organ were negative. The subcellular localization of Hsp 25-immunoreactivity in this study appeared essentially identical to that of actin filaments as demonstrated by confocal microscopy using rhodamine-labeled phalloidin. These immunocytochemical data suggest that the Hsp 25 molecule is involved in reinforcement of the cell layer following cell movement during odontogenesis and in the formation and maintenance of the ruffled border of RA.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Human polymeric immunoglobulin receptor (pIgR) protein was expressed in the adeno-carcinoma cell line HT-29 using a recombinant vaccinia virus transfection method. The pIgR protein was detected as 110- and 120-kDa bands by immunoprecipitation after metabolic labeling. PIgR was released as a free secretory component into the culture supernatant and was detected as a 110-kDa band. PIgR cleavage was investigated by adding the proteinase inhibitor leupeptin or protein kinase C activator PMA. Consistent with previous observations in the Madin Darby canine kidney cell system, cleavage of pIgR was inhibited by leupeptin and enhanced by PMA stimulation, thus indicating that it is regulated by common mechanisms. This experimental system should be very useful for pIgR investigation.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
OBJECTIVE: To study the functional change of an Ala737-->Glu substitution mutant of vWF and the molecular pathological mechanism of this mutant in the type 2A vWD. METHODS: The expression plasmid pSVvWF containing full-length cDNA of vWF was used to site direct mutagenesis by polymerase chain reaction (PCR) and transitorily expressed in the COS-7 cells, vWF: Ag in the supernatant and the cell lysate between wild type and pSVAla737Glu vWF were measured. vWF polymers of the platelet of the patient with the mutation and response to DDAVP treatment of the patient were observed. RESULTS: vWF: Ag level of pSVAla 737Glu vWF was 76.4% and 98.8% of the wild types in the supernatant and cell lysate, respectively. The polymer pattern of extracellular pSVAla737Glu vWF was indistinguishable from that of the wild type, containing all kinds of molecular weight. Increased vWF antigen levels was observed in the patients after DDAVP treatment. CONCLUSION: This mutant did not change the assembly and secretion of vWF. The mutant of vWF Ala737-->Glu resulted in Group II type 2A vWD.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The cDNA encoding the glycoprotein Ib alpha polypeptide has been expressed in COS cells. Transfection with full-length cDNA and a cDNA truncated at an internal XbaI site produced a recombinant polypeptide doublet with estimated molecular weights of 48 and 46 kDa (rGpIb alpha L318) which could be resolved into a single band of molecular weight 36 kDa following digestion with endoglycosidase F. A portion of the truncated polypeptide was retained in the endoplasmic reticulum of COS cells and slowly released. A second fraction was rapidly secreted into COS cell-conditioned medium and could be used for functional studies. Soluble rGpIb alpha L318 harvested from COS cell-conditioned medium inhibited ristocetin-dependent binding of [125I]-vWF to fixed washed human platelets (IC50 20 nM). Binding was inhibited by reduction and alkylation of "rGp1b alpha L318" suggesting the need for a critical disulfide bond to maintain biological activity of the recombinant polypeptide. We conclude that the recombinant polypeptides produced by transfection of GpIb alpha cDNA into heterologous cells are secreted, soluble, and can inhibit vWF binding to platelet GpIb/IX.
Explore the source record for details and available documents.
OBJECTIVE: To detect the in vitro expression of pcDNA3-Eg95 and to observe the immunological effect of the Eg95 DNA vaccine in mice. METHODS: The eukaryotic recombinant plasmid pcDNA3-Eg95 was transfected into HeLa cells with liposome-mediated method. RT-PCR, ELISA and Western blotting were used to analyze the expression of Eg95 mRNA and Eg95 protein, respectively. The BALB/c mice were immunized by pcDNA3-Eg95. Anti-Eg95 IgG and IgG2a in murine serum were determined by ELISA. The proliferation activity of spleen T lymphocytes was tested using MTT assay. RESULTS: Using RT-PCR method, the expression of Eg95 mRNA was confirmed in vitro. The results of ELISA and Western blotting showed that there was a specific Eg95 protein, which can be specifically recognized by anti-sera of Eg95-prokaryotic-expressing protein in pcDNA3-Eg95 transfected HeLa cell lysis. The specific IgG was induced during the 3rd week and continued to increase until week 10. IgG2a was detected after 2 weeks and maintained a higher level till week 10. There was a significant difference of IgG2a level between pcDNA3-Eg95 immunized group and pcDNA3 control (P<0.01). In spleen T cell proliferation response, the stimulation index (SI) in pcDNA3-Eg95 group was higher than that of vector control (P<0.01). CONCLUSION: Eg95 DNA vaccine can induce significant cellular and humoral immune response in mice.