Open AccessComparative mutational analysis of wild-type and stretched tRNA3(Leu) gene promoters.
Author(s) -
Paola Fabrizio,
Annamaria Coppo,
Paolo Fruscoloni,
Piero Benedetti,
Gianfranco Di Segni,
Glauco P. TocchiniValentini
Publication year - 1987
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.84.24.8763
Subject(s) - promoter , genetics , gene , biology , dna , transcription (linguistics) , block (permutation group theory) , gene expression , combinatorics , linguistics , philosophy , mathematics
We demonstrate that, when the yeast tRNA(3Leu) gene is stretched so that the distance between the two portions of the intragenic promoter is increased to 365 base pairs, the A and B blocks remain functional. Mutations in the A block, which show a weak phenotype when inserted in the wild type, exert a dramatic effect when inserted into the stretched gene. Experiments with extensively purified transcription factor tau indicate that the tau B-B block interaction is not influenced by A-B distance; only the ability of tau A to interact with A block sequences is affected, possibly because of the additional free-energy cost of forming a large loop of the intervening DNA.