Poster abstracts

Poster number 177 submitted by Julia Ziebro

Identification of a conserved motif required for Trm732 function in eukaryotes

Julia Ziebro (Department of Chemistry, Northern Kentucky University), Daisy DiVita (Department of Chemistry, Northern Kentucky University), Justen Mamaril (Department of Chemistry, Northern Kentucky University), Gregory M. OConnor (Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA), Katie L. Weiner (Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA), Michael P. Guy (Department of Chemistry, Northern Kentucky University)

Abstract:
Posttranscriptional tRNA modifications are required for accurate and efficient protein synthesis, and defects in several modifications are associated with human diseases. One of the most common tRNA modifications is 2’-O-methylation (Nm). Lack of this modification on residues 32 (Nm32) and 34 (Nm34) in tRNA causes slow growth in yeast and non-syndromic X-linked intellectual disability in humans. In eukaryotes, formation of Nm32 requires the methyltransferase Trm7 and its partner protein Trm732. Human TRM732 (THADA) has been associated with type 2 diabetes and polycystic ovary syndrome in several genome-wide association studies, but it is not clear why Trm732 is required for Nm32 formation. The goal of this study is to determine the role of Trm732 in Nm32 formation. Using site-directed mutagenesis and a growth assay in yeast we have identified a conserved motif in Trm732 that is required for efficient Nm32 formation. We are currently working to identify the cause of the modification defect in Trm732 variants with changes in this motif. Additionally, to study Nm32 and other 2’-O-methylations in metazoans, we are developing a sensitive primer extension-based technique. By coupling this technique with gene knockdown we hope to significantly enhance our ability to study tRNA modifications in diverse eukaryotes.

Keywords: tRNA, trm732, 2-O-methylation