Alternative titles; symbols
HGNC Approved Gene Symbol: TRL-AAG2-3
Cytogenetic location: 14q11.2 Genomic coordinates (GRCh38): 14:20,610,132-20,610,213 (from NCBI)
Chang et al. (1986) isolated and sequenced a cluster of 4 tRNA genes arranged as 2 tandem pairs: proline tRNA(AGG) (TRP1; 189930) and leucine tRNA(AAG) (TRL1), followed by a second proline tRNA(AGG) (TRP2; 189931) and threonine tRNA(UGU) (TRT2; 189933).
Effective immune surveillance by cytotoxic T cells requires newly synthesized polypeptides for presentation by major histocompatibility complex (MHC) class I (see 142800) molecules. These polypeptides are produced not only from conventional AUG-initiated, but also from cryptic non-AUG-initiated, reading frames by distinct translational mechanisms. In biochemical analysis of ribosomal initiation complexes at CUG versus AUG initiation codons, Starck et al. (2012) observed that cells used an elongator leucine-bound transfer RNA (Leu-tRNA) to initiate translation at cryptic CUG start codons. CUG/Leu-tRNA initiation was independent of the canonical initiator tRNA (AUG/Met-tRNAi(Met); see 180621) pathway but required expression of eukaryotic initiation factor 2A (eIF2A; 609234). Thus, Starck et al. (2012) concluded that a tRNA-based translation initiation mechanism allows non-AUG-initiated protein synthesis and supplies peptides for presentation by MHC class I molecules.
Chang et al. (1986) determined that the TRP1 gene is separated by 724 bp from the TRL1 gene. Mitchell et al. (1991) mapped the gene cluster containing TRL1 to chromosome 14q11 near the TCRA gene (see 186880).
Chang, Y. N., Pirtle, I. L., Pirtle, R. M. Nucleotide sequence and transcription of a human tRNA gene cluster with four genes. Gene 48: 165-174, 1986. [PubMed: 3557125] [Full Text: https://doi.org/10.1016/0378-1119(86)90362-8]
Mitchell, A., Bale, A. E., Wang-ge, M., Yi, H. F., White, R., Pirtle, R. M., McBride, O. W. Localization of a DNA segment encompassing four tRNA genes to human chromosome 14q11 and its use as an anchor locus for linkage analysis. Genomics 11: 1063-1070, 1991. [PubMed: 1686015] [Full Text: https://doi.org/10.1016/0888-7543(91)90033-b]
Starck, S. R., Jiang, V., Pavon-Eternod, M., Prasad, S., McCarthy, B., Pan, T., Shastri, N. Leucine-tRNA initiates at CUG start codons for protein synthesis and presentation by MHC class I. Science 336: 1719-1723, 2012. [PubMed: 22745432] [Full Text: https://doi.org/10.1126/science.1220270]