scholarly journals Introduction and recovery of a selectable bacterial gene from the genome of mammalian cells.

1982 ◽  
Vol 2 (8) ◽  
pp. 966-976 ◽  
Author(s):  
M L Breitman ◽  
L C Tsui ◽  
M Buchwald ◽  
L Siminovitch
Keyword(s):  
Molecular Weight ◽  
Cell Line ◽  
Cell Lines ◽  
Mammalian Cells ◽  
Dna Molecules ◽  
High Molecular Weight Dna ◽  
Bacterial Gene ◽  
E Coli ◽  
Transformed Cell ◽  
Transformed Cell Lines

The simian virus 40 (SV40)-pBR322 recombinant, pSV2, carrying the origin of SV40 replication and the gpt gene of Escherichia coli, has been stably introduced into Chinese hamster ovary hprt- cells. All gpt-transformed cell lines were found to contain one or more insertions of pSV2 sequences exclusively associated with high-molecular-weight DNA. Additional analyses showed that at least one integrated copy in each cell line retained an intact gpt gene and flanking SV40 sequences required for expression of xanthine-guanine phosphoribosyltransferase. Most cell lines contained pSV2 sequences which had integrated with partial sequence duplication. Upon fusion with COS-1 cells, a simian cell line permissive for autonomous pSV2 replication, most gpt-transformed cell lines produced low-molecular-weight DNA molecules related to pSV2. The majority of these replicating DNAs were indistinguishable from the original transfecting plasmid in both size and restriction enzyme cleavage pattern. In addition, the recovered DNA molecules were able to confer ampicillin resistance to E. coli and to transform mouse L cells and Gpt- E. coli to a Gpt+ phenotype. These studies indicate that all of the genetic information carried by this SV40-plasmid recombinant can be introduced into and retrieved from the genome of mammalian cells.

scholarly journals Introduction and recovery of a selectable bacterial gene from the genome of mammalian cells

1982 ◽  
Vol 2 (8) ◽  
pp. 966-976
Author(s):  
M L Breitman ◽  
L C Tsui ◽  
M Buchwald ◽  
L Siminovitch
Keyword(s):  
Molecular Weight ◽  
Cell Line ◽  
Cell Lines ◽  
Mammalian Cells ◽  
Dna Molecules ◽  
High Molecular Weight Dna ◽  
Bacterial Gene ◽  
E Coli ◽  
Transformed Cell ◽  
Transformed Cell Lines

The simian virus 40 (SV40)-pBR322 recombinant, pSV2, carrying the origin of SV40 replication and the gpt gene of Escherichia coli, has been stably introduced into Chinese hamster ovary hprt- cells. All gpt-transformed cell lines were found to contain one or more insertions of pSV2 sequences exclusively associated with high-molecular-weight DNA. Additional analyses showed that at least one integrated copy in each cell line retained an intact gpt gene and flanking SV40 sequences required for expression of xanthine-guanine phosphoribosyltransferase. Most cell lines contained pSV2 sequences which had integrated with partial sequence duplication. Upon fusion with COS-1 cells, a simian cell line permissive for autonomous pSV2 replication, most gpt-transformed cell lines produced low-molecular-weight DNA molecules related to pSV2. The majority of these replicating DNAs were indistinguishable from the original transfecting plasmid in both size and restriction enzyme cleavage pattern. In addition, the recovered DNA molecules were able to confer ampicillin resistance to E. coli and to transform mouse L cells and Gpt- E. coli to a Gpt+ phenotype. These studies indicate that all of the genetic information carried by this SV40-plasmid recombinant can be introduced into and retrieved from the genome of mammalian cells.

Regulation of cell growth, c-myc mRNA, and 1,25-(OH)2 vitamin D3 receptor in C3H/10T1/2 mouse embryo fibroblasts by calcipotriol and 1,25-(OH)2 vitamin D3

1992 ◽  
Vol 126 (1) ◽  
pp. 75-79 ◽  
Author(s):  
Torleif Trydal ◽  
Johan R. Lillehaug ◽  
Lage Aksnes ◽  
Dagfinn Aarskog
Keyword(s):  
Cell Growth ◽  
Cell Line ◽  
Cell Lines ◽  
Vitamin D3 ◽  
Mouse Embryo ◽  
Transformed Cell ◽  
Mouse Embryo Fibroblasts ◽  
Transformed Cell Line ◽  
Embryo Fibroblasts ◽  
Transformed Cell Lines

Calcipotriol is a synthetic 1,25-(OH)2D3 analogue with high affinity for the 1,25-(OH)2D3 receptor, but with a lower affinity than 1,25-(OH)2D3 for vitamin D binding protein in serum. The inhibitory action of calcipotriol and 1,25-(OH)2D3 on proliferation of C3H/10T1/2 mouse embryo fibroblasts was examined in the non-transformed cell line CI 8 and in the two transformed, tumorigenic cell lines Cl 16 and TPA 482. Upon exposure to 10 nmol/l calcipotriol or 1,25-(OH)2D3, the proliferation of Cl 8 cell line was almost completely suppressed, whereas both hormones had no effect on the cell lines Cl 16 and TPA 482. Calcipotriol was at least as effective as 1,25-(OH)2D3 in inducing up-regulation of the 1,25-(OH)2D3 receptor. Displacement studies showed no difference between calcipotriol and 1,25-(OH)2D3 in the affinity for the receptor present in Cl 8 or Cl 16 cell extracts. Furthermore, the inhibition of cell growth in Cl 8 cells by calcipotriol was not accompanied by any consistent change in the steady-state expression of c-myc mRNA. In conclusion, calcipotriol had potent growth inhibitory effect on the non-transformed cell line similar to 1,25-(OH)2D3. In the transformed cell lines, calcipotriol did not inhibit proliferation despite potent up-regulation of the 1,25-(OH)2D3 receptor.

scholarly journals Multiple RSV strains infecting HEp-2 and A549 cells reveal cell line-dependent differences in resistance to RSV infection.

2021 ◽  
Author(s):  
Anubama Rajan ◽  
Felipe-Andres Piedra ◽  
Letisha Aideyan ◽  
Trevor McBride ◽  
Matthew J Robertson ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Line ◽  
Cell Lines ◽  
A549 Cells ◽  
Viral Gene Expression ◽  
Model Systems ◽  
Viral Gene ◽  
Transformed Cell ◽  
Syncytial Virus ◽  
Transformed Cell Lines

Respiratory syncytial virus (RSV) is a leading cause of pediatric acute respiratory infection worldwide. There are currently no approved vaccines or antivirals to combat RSV disease. A few transformed cell lines and two historic strains have been extensively used to study RSV. Here we report a thorough molecular and cell biological characterization of HEp-2 and A549 cells infected with four strains of RSV representing both major subgroups as well as historic and more contemporaneous genotypes -- [RSV/A/Tracy (GA1), RSV/A/Ontario (ON), RSV/B/18537 (GB1), RSV/B/Buenos Aires (BA)] -- via measurements of viral replication kinetics and viral gene expression, immunofluorescence-based imaging of gross cellular morphology and cell-associated RSV, and measurements of host response including transcriptional changes and levels of secreted cytokines and growth factors. Our findings strongly suggest 1) the existence of a conserved difference in gene expression between RSV subgroups A and B; 2) the A549 cell line is a more stringent and natural host of replicating RSV than the HEp-2 cell line; and 3) consistent with previous studies, determining the full effects of viral genetic variation in RSV pathogenesis requires model systems as tractable as transformed cell lines but better representative of the human host.

scholarly journals Porcine pancreatic ductal epithelial cells transformed with KRASG12D and SV40T are tumorigenic

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Katie L. Bailey ◽  
Sara B. Cartwright ◽  
Neesha S. Patel ◽  
Neeley Remmers ◽  
Audrey J. Lazenby ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Animal Model ◽  
Epithelial Cells ◽  
Cell Line ◽  
Cell Lines ◽  
Large Animal Model ◽  
Large Animal ◽  
Transformed Cell ◽  
Transformed Cell Line ◽  
Transformed Cell Lines

AbstractWe describe our initial studies in the development of an orthotopic, genetically defined, large animal model of pancreatic cancer. Primary pancreatic epithelial cells were isolated from pancreatic duct of domestic pigs. A transformed cell line was generated from these primary cells with oncogenic KRAS and SV40T. The transformed cell lines outperformed the primary and SV40T immortalized cells in terms of proliferation, population doubling time, soft agar growth, transwell migration and invasion. The transformed cell line grew tumors when injected subcutaneously in nude mice, forming glandular structures and staining for epithelial markers. Future work will include implantation studies of these tumorigenic porcine pancreatic cell lines into the pancreas of allogeneic and autologous pigs. The resultant large animal model of pancreatic cancer could be utilized for preclinical research on diagnostic, interventional, and therapeutic technologies.

scholarly journals Porcine pancreatic ductal epithelial cells transformed with KRAS G12D and SV40T are tumorigenic

2021 ◽  
Author(s):  
Katie L. Bailey ◽  
Sara B. Cartwright ◽  
Neesha S. Patel ◽  
Neeley Remmers ◽  
Audrey J. Lazenby ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Animal Model ◽  
Epithelial Cells ◽  
Cell Line ◽  
Cell Lines ◽  
Large Animal Model ◽  
Large Animal ◽  
Transformed Cell ◽  
Transformed Cell Line ◽  
Transformed Cell Lines

Abstract We describe our initial studies in the development of an orthotopic, genetically-defined, large animal model of pancreatic cancer. Primary pancreatic epithelial cells were isolated from pancreatic duct of domestic pigs. A transformed cell line was generated from these primary cells with oncogenic KRAS and SV40T. The transformed cell lines outperformed the primary and SV40T immortalized cells in terms of proliferation, population doubling time, soft agar growth, transwell migration and invasion. The transformed cell line grew tumors when injected subcutaneously in nude mice, forming glandular structures and staining for epithelial markers. Future work will include implantation studies of these tumorigenic porcine pancreatic cell lines into the pancreas of allogeneic and autologous pigs. The resultant large animal model of pancreatic cancer could be utilized for preclinical research on diagnostic, interventional, and therapeutic technologies.

The antiproliferative effects of agmatine correlate with the rate of cellular proliferation

2007 ◽  
Vol 293 (2) ◽  
pp. C705-C711 ◽  
Author(s):  
Masato Isome ◽  
Mark J. Lortie ◽  
Yasuko Murakami ◽  
Eva Parisi ◽  
Senya Matsufuji ◽  
...  
Keyword(s):  
Cell Line ◽  
Cell Lines ◽  
Cellular Proliferation ◽  
Intracellular Accumulation ◽  
3T3 Cells ◽  
Antiproliferative Effects ◽  
Transformed Cell ◽  
Polyamine Transport ◽  
Transformed Cell Lines ◽  
Nih 3T3

Polyamines are small cationic molecules required for cellular proliferation. Agmatine is a biogenic amine unique in its capacity to arrest proliferation in cell lines by depleting intracellular polyamine levels. We previously demonstrated that agmatine enters mammalian cells via the polyamine transport system. As polyamine transport is positively correlated with the rate of cellular proliferation, the current study examines the antiproliferative effects of agmatine on cells with varying proliferative kinetics. Herein, we evaluate agmatine transport, intracellular accumulation, and its effects on antizyme expression and cellular proliferation in nontransformed cell lines and their transformed variants. H-ras- and Src-transformed murine NIH/3T3 cells (Ras/3T3 and Src/3T3, respectively) that were exposed to exogenous agmatine exhibit increased uptake and intracellular accumulation relative to the parental NIH/3T3 cell line. Similar increases were obtained for human primary foreskin fibroblasts relative to a human fibrosarcoma cell line, HT1080. Agmatine increases expression of antizyme, a protein that inhibits polyamine biosynthesis and transport. Ras/3T3 and Src/3T3 cells demonstrated augmented increases in antizyme protein expression relative to NIH/3T3 in response to agmatine. All transformed cell lines were significantly more sensitive to the antiproliferative effects of agmatine than nontransformed lines. These effects were attenuated in the presence of exogenous polyamines or inhibitors of polyamine transport. In conclusion, the antiproliferative effects of agmatine preferentially target transformed cell lines due to the increased agmatine uptake exhibited by cells with short cycling times.

scholarly journals Porcine pancreatic ductal epithelial cells transformed with KRASG12D and SV40T are tumorigenic

2021 ◽  
Author(s):  
Katie Bailey ◽  
Sara B. Cartwright ◽  
Neesha S. Patel ◽  
Neeley Remmers ◽  
Audrey J. Lazenby ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Animal Model ◽  
Epithelial Cells ◽  
Cell Line ◽  
Cell Lines ◽  
Large Animal Model ◽  
Large Animal ◽  
Transformed Cell ◽  
Transformed Cell Line ◽  
Transformed Cell Lines

AbstractWe describe our initial studies in the development of an orthotopic, genetically-defined, large animal model of pancreatic cancer. Primary pancreatic epithelial cells were isolated from pancreatic duct of domestic pigs. A transformed cell line was generated from these primary cells with oncogenic KRAS and SV40T. The transformed cell lines outperformed the primary and SV40T immortalized cells in terms of proliferation, population doubling time, soft agar growth, transwell migration and invasion. The transformed cell line grew tumors when injected subcutaneously in nude mice, forming glandular structures and staining for epithelial markers. Future work will include implantation studies of these tumorigenic porcine pancreatic cell lines into the pancreas of allogeneic and autologous pigs. The resultant large animal model of pancreatic cancer could be utilized for preclinical research on diagnostic, interventional, and therapeutic technologies.

scholarly journals Molecular analysis of ethyl methanesulfonate-induced reversion of a chromosomally integrated mutant shuttle vector gene in mammalian cells.

1988 ◽  
Vol 8 (10) ◽  
pp. 4185-4189 ◽  
Author(s):  
J A Greenspan ◽  
F M Xu ◽  
R L Davidson
Keyword(s):  
Cell Line ◽  
Cell Lines ◽  
Dna Sequences ◽  
Mammalian Cells ◽  
Molecular Mechanisms ◽  
Shuttle Vector ◽  
Ethyl Methanesulfonate ◽  
Wild Type ◽  
Single Base ◽  
Type Sequence

The molecular mechanisms of ethyl methanesulfonate-induced reversion in mammalian cells were studied by using as a target a gpt gene that was integrated chromosomally as part of a shuttle vector. Murine cells containing mutant gpt genes with single base changes were mutagenized with ethyl methanesulfonate, and revertant colonies were isolated. Ethyl methanesulfonate failed to increase the frequency of revertants for cell lines with mutant gpt genes carrying GC----AT transitions or AT----TA transversions, whereas it increased the frequency 50-fold to greater than 800-fold for cell lines with mutant gpt genes carrying AT----GC transitions and for one cell line with a GC----CG transversion. The gpt genes of 15 independent revertants derived from the ethyl methanesulfonate-revertible cell lines were recovered and sequenced. All revertants derived from cell lines with AT----GC transitions had mutated back to the wild-type gpt sequence via GC----AT transitions at their original sites of mutation. Five of six revertants derived from the cell line carrying a gpt gene with a GC----CG transversion had mutated via GC----AT transition at the site of the original mutation or at the adjacent base in the same triplet; these changes generated non-wild-type DNA sequences that code for non-wild-type amino acids that are apparently compatible with xanthine-guanine phosphoribosyltransferase activity. The sixth revertant had mutated via CG----GC transversion back to the wild-type sequence. The results of this study define certain amino acid substitutions in the xanthine-guanine phosphoribosyltransferase polypeptide that are compatible with enzyme activity. These results also establish mutagen-induced reversion analysis as a sensitive and specific assay for mutagenesis in mammalian cells.

Sign in / Sign up

Export Citation Format

Share Document