Poster abstracts

Poster number 41 submitted by Christina Ross

Site-specific identification of m6A RNA modification in HIV-1 genomic RNA 5'UTR

Christina Ross (Department of Chemistry and Biochemistry, Center for Retrovirus Research, and Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210 ), Karin Musier-Forsyth (Department of Chemistry and Biochemistry, Center for Retrovirus Research, and Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210 )

Abstract:
RNA modifications affect all aspects of RNA biology, likely impacting processes in viral replication such as RNA localization, stability, and assembly. To assemble virions, HIV-1 must select full-length genomic RNA (gRNA) from the cytoplasmic pool of cellular and viral RNA. The viral polyprotein Gag orchestrates the packaging process via specific interactions between within the gRNA 5'UTR. Two N-6-methyladenosine (m6A) modifications have been previously identified in the 5'UTR using low resolution m6A-sequencing-based techniques. One of these modifications is located in the viral RNA packaging signal, proximal to a known site of Gag interaction. The presence of both modifications has recently been proposed to play a critical role in down-regulating gRNA packaging. Thus, we hypothesize m6A modifications in the HIV-1 5'UTR influence viral replication and assembly through modulating RNA structure and Gag interactions. Using an approach related to SCARLET (site-specific cleavage and radioactive-labeling followed by ligation-assisted extraction and thin-layer chromatography), we purified RNA from cells transfected with HIV-1 plasmid to determine the stoichiometry of m6A on the specific sites in the gRNA 5'UTR . Future work will investigate the impact of m6A on gRNA packaging by determining the levels of m6A at the 5'UTR sites on cellular versus packaged gRNA.

Keywords: RNA modification, m6A, HIV-1