Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1997-6-19
pubmed:abstractText
We previously described a system for exogenous control of gene expression in procyclic trypanosomes which depends upon the binding of a tetracycline-inducible repressor to operators situated at the transcriptional start site of the PARP promoter. The recombinant constructs are introduced into non-transcribed spacers of the ribosomal RNA repeat, in an orientation opposite to that of rRNA transcription. Using this system, gene expression could be regulated over four orders of magnitude, but it was not possible to express toxic gene products because selection of recombinant trypanosomes depended on the activity of the inducible promoter. We describe here the characteristics of vectors that include two promoters: a tetracycline-inducible one to drive expression of the toxic products, and a constitutive one to drive transcription of the selectable marker. Relatively high levels of non-induced (non-tetracycline-dependent) expression were seen in some trypanosome clones; this was not usually due to read-through of multiple tandemly-integrated plasmids or tet operator mutations. A variety of constructs differing in resistance marker, 3'-untranslated region (3'-UTR) and the nature of the constitutive promoter was tested. Vectors allowing the successful expression of toxic and other genes in both life cycle stages with regulation factors of up to 700 fold were obtained.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0166-6851
pubmed:author
pubmed:issnType
Print
pubmed:volume
85
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
99-112
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Vectors for inducible expression of toxic gene products in bloodstream and procyclic Trypanosoma brucei.
pubmed:affiliation
Zentrum für Molekular Biologie, Heidelberg, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't