Molecular basis of gene regulation by the THI-box riboswitch
Por:
Ontiveros-Palacios N., Smith A.M., Grundy F.J., Soberon M., Henkin T.M., Miranda-Ríos J.
Publicada:
1 feb 2008
Resumen:
Riboswitches are genetic control elements located mainly within the 51 untranslated regions of messenger RNAs. These RNA elements undergo conformational changes that modulate gene expression upon binding of regulatory signals including vitamins, amino acids, nucleobases and uncharged tRNA. The thiamin pyrophosphate (TPP)-binding riboswitch (THI-box) is found in all three kingdoms of life and can regulate gene expression at the levels of premature termination of transcription, initiation of translation and mRNA splicing. The THII-box is composed of two parallel stacked helices bound by another helix in a three-way junction. We performed an in vivo expression analysis of mutants with substitutions in conserved bases located at the interior and terminal loops of the Escherichia coli thiM THI-box, which is transiationally regulated, and observed two different phenotypic classes. One class exhibited high expression during growth in the presence or absence of thiamin, while the second class
Filiaciones:
Ontiveros-Palacios N.:
Univ Nacl Autonoma Mexico, Dept Mol Microbiol, Inst Biotechnol, Cuernavaca 62250, Morelos, Mexico
Smith A.M.:
Department of Microbiology, Ohio State University, Columbus, OH, United States
Grundy F.J.:
Department of Microbiology, Ohio State University, Columbus, OH, United States
Soberon M.:
Univ Nacl Autonoma Mexico, Dept Mol Microbiol, Inst Biotechnol, Cuernavaca 62250, Morelos, Mexico
Henkin T.M.:
Department of Microbiology, Ohio State University, Columbus, OH, United States
Miranda-Ríos J.:
Univ Nacl Autonoma Mexico, Dept Mol Microbiol, Inst Biotechnol, Cuernavaca 62250, Morelos, Mexico
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