GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com


Jump to: navigation, search

Machado, CR, Praekelt, UM, de Oliveira, RC, Barbosa, AC, Byrne, KL, Meacock, PA and Menck, CF (1997) Dual role for the yeast THI4 gene in thiamine biosynthesis and DNA damage tolerance. J. Mol. Biol. 273:114-21


The THI4 gene of Saccharomyces cerevisiae encodes an enzyme of the thiamine biosynthetic pathway. The plant homolog thi1, from Arabidopsis thaliana, is also involved in thiamine biosynthesis; but was originally cloned due to its capacity to complement DNA repair deficient phenotypes in Escherichia coli. Here, the behavior of a thi4 disrupted strain was examined for increased sensitivity to treatment with the DNA damaging agents ultraviolet radiation (UV, 254 nm) and methyl methanesulfonate (MMS). Although the thi4 null mutant showed a similar level of survival as the wild-type strain, a higher frequency of respiratory mutants was induced by the two treatments. A similar phenotype was seen with wild-type strains expressing an antisense THI4 construct. Further analysis of respiratory mutants revealed that these were due to mutations of mitochondrial DNA (mtDNA) rather than nuclear DNA, consisting of rho-petite mutants. Moreover, the frequency of mutations was unaffected by the presence or absence of thiamine in the growth medium, and the defect leading to induction of petites in the thi4 mutant was corrected by expression of the Arabidopsis thi1 gene. Thus, Thi4 and its plant homolog appear to be dual functional proteins with roles in thiamine biosynthesis and mitochondrial DNA damage tolerance.


PubMed Online version:10.1006/jmbi.1997.1302


Arabidopsis/genetics; Arabidopsis Proteins; DNA Damage; DNA Mutational Analysis; DNA, Mitochondrial/genetics; DNA-Binding Proteins/genetics; DNA-Binding Proteins/metabolism; Fluorescent Dyes; Fungal Proteins/genetics; Fungal Proteins/metabolism; Fungal Proteins/physiology; Gene Expression Regulation, Fungal; Genes, Fungal; Genetic Complementation Test; Indoles/metabolism; Methyl Methanesulfonate/pharmacology; Microscopy, Fluorescence; Mutagenesis; Oxygen Consumption; Phenotype; Plant Proteins/genetics; Plant Proteins/metabolism; RNA, Antisense/genetics; RNA, Antisense/pharmacology; Saccharomyces cerevisiae/cytology; Saccharomyces cerevisiae/genetics; Saccharomyces cerevisiae/metabolism; Saccharomyces cerevisiae Proteins; Thiamine/biosynthesis; Transcription Factors/genetics; Transcription Factors/metabolism; Ultraviolet Rays



Gene product Qualifier GO ID GO term name Evidence Code with/from Aspect Notes Status

See also


See Help:References for how to manage references in GONUTS.