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Kirill Borziak BS: Biochemistry, Cellular & Molecular Biology, University of Tennessee, Knoxville Rotation Student |
Description of Research
The essence of signal transduction, in both eukaryotes and prokaryotes, is the conversion of a molecular signal into gene activation or other cellular responses. We are searching for universal sensory modules that detect signals in both prokaryotes and eukaryotes. Here we report the identification of one such module, the FIST domain, which is found in major signal transduction pathways in prokaryotes (one-component, two-component, and chemotaxis regulatory systems) and eukaryotes (F-box-containing components of the ubiquitin pathway). FIST-containing proteins are exclusively cytoplasmic and are proposed to detect small ligands, likely amino acids, and relay the information to pathways controlling gene expression, intracellular levels of cyclic di-GMP and flagellar motility. Analysis of gene order using the MIST database reveals that FIST-containing proteins are often encoded in close proximity to amino acid permeases, asparagine synthases, peptidases and eukaryotic F-box proteins that are known to bind auxin, a plant hormone and derivative of tryptophan. This genome context analysis further supports the hypothesis that FIST is an amino acid sensor.
Publications