During eukaryotic translation initiation, ribosomal 43S complexes scan mRNAs for the correct AUG codon at which to begin translation. Start codon recognition triggers GTP hydrolysis, committing the complex to engagement at that point on the mRNA. While fidelity at this step is essential, the nature of the codon recognition event and the mechanism by which it activates GTP hydrolysis are poorly understood. Here we report the changes that occur within the 43S.mRNA complex in response to AUG codon recognition. eIF1 and eIF1A are key players in assembly of 43S.mRNA complexes capable of locating initiation codons. We observed FRET between these two factors when bound to the 40S subunit. Using steady-state FRET, anisotropy, and kinetic analyses, we demonstrate that start codon recognition results in a conformational change and release of eIF1 from the ribosome. These rearrangements probably play a role in triggering GTP hydrolysis and committing the complex to downstream events.
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http://dx.doi.org/10.1016/j.molcel.2004.11.051 | DOI Listing |
Curr Issues Mol Biol
December 2024
College of Agriculture and Biology, Liaocheng University, Liaocheng 252000, China.
To clone DNA sequences quickly and precisely into plasmids is essential for molecular biology studies. Some cloning vectors have been developed for the cloning of PCR products, including blunt-end and T-A cloning. However, different plasmids are required for the cloning of PCR products with blunt ends and 3' A overhang ends.
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Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Shanghai, 200438, China.
New insights into the phylogeny of species in the family Thymelaeaceae and support of the recognition of D. genkwa and D. aurantiaca as species in the genus Wikstroemia are provided.
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Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892.
Establishing genotype-phenotype correlations in disorders of hereditary endocrine neoplasia is important for clinical screening, genetic counseling, prognostication, surveillance, and surgical strategy, and may also provide clues about disease pathogenesis. Important genotype-phenotype correlations are recognized, for example, in pheochromocytoma/paraganglioma and multiple endocrine neoplasia type 2A. The presence of such correlations has been less clear in other familial endocrine disorders associated with primary hyperparathyroidism including multiple endocrine neoplasia type 1 (MEN1), and the hyperparathyroidism-jaw tumor syndrome (HPT-JT).
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Department of Biochemistry, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA. Electronic address:
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