Download MendeleyEukaryotic cytosolic and mitochondrial phenylalanyl-tRNA synthetases catalyze the charging of tRNA with the meta-tyrosine
Klipcan, L., Moor, N., Kessler, N., Safro, M.G.(2009) Proc Natl Acad Sci U S A 106: 11045-11048
- PubMed: 19549855
- DOI: https://doi.org/10.1073/pnas.0905212106
- Primary Citation of Related Structures:
3HFV, 3HFZ - PubMed Abstract:
The accumulation of proteins damaged by reactive oxygen species (ROS), conventionally regarded as having pathological potentials, is associated with age-related diseases such as Alzheimer's, atherosclerosis, and cataractogenesis. Exposure of the aromatic amino acid phenylalanine to ROS-generating systems produces multiple isomers of tyrosine: m-tyrosine (m-Tyr), o-tyrosine (o-Tyr), and the standard p-tyrosine (Tyr). Previously it was demonstrated that exogenously supplied, oxidized amino acids could be incorporated into bacterial and eukaryotic proteins. It is, therefore, likely that in many cases, in vivo-damaged amino acids are available for de novo synthesis of proteins. Although the involvement of aminoacyl-tRNA synthetases in this process has been hypothesized, the specific pathway by which ROS-damaged amino acids are incorporated into proteins remains unclear. We provide herein evidence that mitochondrial and cytoplasmic phenylalanyl-tRNA synthetases (HsmtPheRS and HsctPheRS, respectively) catalyze direct attachment of m-Tyr to tRNA(Phe), thereby opening the way for delivery of the misacylated tRNA to the ribosome and incorporation of ROS-damaged amino acid into eukaryotic proteins. Crystal complexes of mitochondrial and bacterial PheRSs with m-Tyr reveal the net of highly specific interactions within the synthetic and editing sites.
Organizational Affiliation:
Department of Structural Biology, Weizmann Institute of Science, 76100 Rehovot, Israel.
