Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2000-3-2
pubmed:abstractText
The objective of this work was to further develop a tetracycline repressor (TetR) protein system that allows control of transgene expression. First, to circumvent the need for a binary approach, a single plasmid design was constructed and tested in tissue culture. To indirectly assay integrations that express the synthetic transcription factor (rtTA), a bicistronic gene was built which included an internal ribosome entry site (IRES) and a green fluorescent protein coding region (GFP) on the same expression cassette as the coding region of rtTA (pTetGREEN). This construct did not produce fluorescent colonies when stably integrated and provided minimal expression of GFP in the face of adequate expression of rtTA. The coding region for TetR was then altered by introducing 156 silent point mutations to simulate mammalian genes. Replacement of wild-type TetR gene (tetR) in pTetGREEN with 'mammalianized' tetR provided GFP expression. Adjustment of codon usage in the tetR region of rtTA nearly doubled the expression level of functional rtTA. To increase the number of rtTA expressing lines, the chicken egg-white lysozyme matrix attachment region (MAR) was introduced into the single plasmid design just upstream of the tetracycline operators (tetO). Inclusion of the MAR doubled the number of colonies that expressed rtTA (44% vs 88%). With the modifications described here, the number of lines that express rtTA and provide induction from a single plasmid design can be increased by the inclusion of a MAR and the level of rtTA expression can be further increased by adjusting the base composition of the TetR coding region. The MAR also insulates the inducible gene from the promoter driving rtTA.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0962-8819
pubmed:author
pubmed:issnType
Print
pubmed:volume
8
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
371-81
pubmed:dateRevised
2006-4-21
pubmed:meshHeading
pubmed-meshheading:10669945-Amino Acid Sequence, pubmed-meshheading:10669945-Animals, pubmed-meshheading:10669945-Base Sequence, pubmed-meshheading:10669945-CHO Cells, pubmed-meshheading:10669945-Codon, pubmed-meshheading:10669945-Cricetinae, pubmed-meshheading:10669945-Gene Expression Regulation, pubmed-meshheading:10669945-Genetic Engineering, pubmed-meshheading:10669945-Genetic Vectors, pubmed-meshheading:10669945-Green Fluorescent Proteins, pubmed-meshheading:10669945-Indicators and Reagents, pubmed-meshheading:10669945-Luminescent Proteins, pubmed-meshheading:10669945-Molecular Sequence Data, pubmed-meshheading:10669945-Nuclear Matrix, pubmed-meshheading:10669945-Point Mutation, pubmed-meshheading:10669945-Repressor Proteins, pubmed-meshheading:10669945-Tetracycline, pubmed-meshheading:10669945-Transgenes
pubmed:year
1999
pubmed:articleTitle
Codon optimization, genetic insulation, and an rtTA reporter improve performance of the tetracycline switch.
pubmed:affiliation
Gene Evaluation and Mapping Laboratory, LPSI, BARC, Beltsville, MD 20705, USA.
pubmed:publicationType
Journal Article