Poster abstracts
Poster number 37 submitted by Natalie Creech
Determining the role of the tRNA methyltransferase Trm7:Trm734 in repression of TY1 elements in yeast
Natalie Creech (Department of Chemistry and Biochemistry, Northern Kentucky University), Ruofei Ding (Department of Chemistry and Biochemistry, Northern Kentucky University), Holly M. Funk (Department of Chemistry and Biochemistry, Northern Kentucky University), Emma Nasipova (Department of Chemistry and Biochemistry, Northern Kentucky University), Faith Meghrian (Department of Chemistry and Biochemistry, Northern Kentucky University), Michael P. Guy (Department of Chemistry and Biochemistry, Northern Kentucky University)
Abstract:
Post-transcriptional tRNA modifications are required for efficient protein translation. In yeast, the Trm7 methyltransferase forms a complex with Trm734 to modify tRNA at position 34. In humans, mutations in the TRM7 homolog FTSJ1 cause intellectual disability. In yeast, retrotransposons replicate through reverse transcription of a region of RNA that can then integrate into new sites throughout the genome. Increased TY1 transposition can lead to damage of once-functional genes. In a previous screen, TRM7 and TRM734 were identified as being involved in repression of TY1 transposition, although it is unclear whether this effect is direct or indirect. We hypothesize that loss of TRM7 or TRM734 leads to increased TY1 transposition because of lowered expression due to defects in the translation of other genes involved in limiting TY1 transposition. We analyzed the codon content of genes known to suppress TY1 transposition and selected four genes which had higher than expected Phe codon content, becauseTrm7 and Trm734 are important for post-transcriptional modification of the tRNAPhe anti-codon loop. We are testing genetic interactions to determine if TRM7 and TRM734 are directly or indirectly involved in TY1 transposition. In a parallel approach, to test expression levels in yeast, tagged proteins of interest will be transformed into strains lacking TRM7 and TRM734. Expression of the four TY1-associated genes will then be compared to that in wild type strains. By performing these experiments, we will better understand the role of Trm7 and Trm734 in the translation of Phe-rich genes.
Keywords: tRNA, yeast, modifications