Linked Life Data

8061322

Source:http://linkedlifedata.com/resource/pubmed/id/8061322

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1994-9-22
pubmed:abstractText
Previously we have demonstrated gene targeting in plants after Agrobacterium-mediated transformation. In these initial experiments a transgenic tobacco line 104 containing a T-DNA insertion with a defective neomycin phosphotransferase (nptII) gene was transformed with a repair construct containing an otherwise defective nptII gene. Homologous recombination between the chromosomally located target and the incoming complementary defective nptII construct generated an intact nptII gene and led to a kanamycin-resistant (Kmr) phenotype. The gene targeting frequency was 1 x 10(-5). In order to compare direct gene transfer and Agrobacterium-mediated transformation with respect to gene targeting we transformed the same transgenic tobacco line 104 via electroporation. A total of 1.35 x 10(8) protoplasts were transformed with the repair construct. Out of nearly 221,000 transformed cells 477 Kmr calli were selected. Screening the Kmr calli via PCR for recombination events revealed that in none of these calli gene targeting had occurred. To establish the origin of the high number of Kmr calli in which gene targeting had not occurred we analysed plants regenerated from 24 Kmr calli via PCR and sequence analysis. This revealed that in 21 out of 24 plants analysed the 5'-deleted nptII gene was fused to the hygromycin phosphotransferase (hpt) gene that was also present on the repair construct. Sequence analysis of 7 hpt/nptII gene fusions showed that they all contained a continuous open reading frame. The absence of significant homology at the fusion site indicated that fusion occurred via a process of illegitimate recombination. Therefore, illegitimate recombination between an introduced defective gene and another gene present on the repair construct or the chromosome has to be taken into account as a standard byproduct in gene targeting experiments.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0167-4412
pubmed:author
pubmed:issnType
Print
pubmed:volume
25
pubmed:geneSymbol
hpt, nptII
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
721-33
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:8061322-Amino Acid Sequence, pubmed-meshheading:8061322-Base Sequence, pubmed-meshheading:8061322-Blotting, Southern, pubmed-meshheading:8061322-Cloning, Molecular, pubmed-meshheading:8061322-DNA, pubmed-meshheading:8061322-DNA, Bacterial, pubmed-meshheading:8061322-DNA Primers, pubmed-meshheading:8061322-Electroporation, pubmed-meshheading:8061322-Kanamycin Kinase, pubmed-meshheading:8061322-Molecular Sequence Data, pubmed-meshheading:8061322-Phenotype, pubmed-meshheading:8061322-Phosphotransferases (Alcohol Group Acceptor), pubmed-meshheading:8061322-Plants, Genetically Modified, pubmed-meshheading:8061322-Plants, Toxic, pubmed-meshheading:8061322-Plasmids, pubmed-meshheading:8061322-Polymerase Chain Reaction, pubmed-meshheading:8061322-Recombination, Genetic, pubmed-meshheading:8061322-Sequence Deletion, pubmed-meshheading:8061322-Tobacco
pubmed:year
1994
pubmed:articleTitle
Non-recombinant background in gene targeting: illegitimate recombination between a hpt gene and a defective 5' deleted nptII gene can restore a Kmr phenotype in tobacco.
pubmed:affiliation
MOGEN International nv, Leiden, Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't