An anti-TRAP (AT) protein, a factor of previously unknown function, conveys the metabolic signal that the cellular transfer RNA for tryptophan (tRNATrp) is predominantly uncharged. Expression of the operon encoding AT is induced by uncharged tRNATrp. AT associates with TRAP, the trp operon attenuation protein, and inhibits its binding to its target RNA sequences. This relieves TRAP-mediated transcription termination and translation inhibition, increasing the rate of tryptophan biosynthesis. AT binds to TRAP primarily when it is in the tryptophan-activated state. The 53-residue AT polypeptide is homologous to the zinc-binding domain of DnaJ. The mechanisms regulating tryptophan biosynthesis in Bacillus subtilis differ from those used by Escherichia coli.
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http://dx.doi.org/10.1126/science.1062187 | DOI Listing |
Clin Rheumatol
January 2025
Department of Rheumatology, Guang'anmen Hospital, Chinese Academy of Chinese Medical Sciences, Beijing, People's Republic of China.
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January 2025
State Key Laboratory of Livestock and Poultry Breeding, College of Animal Science, South China Agricultural University, Guangzhou, 510642, China.
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Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. Electronic address:
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Postgraduate Program in Veterinary Sciences, Faculty of Veterinary Medicine, Federal University of Uberlândia, Brazil; Postgraduate Program in Genetics and Biochemistry, Federal University of Uberlândia, Brazil.
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