Download MendeleyStructural basis for transcriptional start site control of HIV-1 RNA fate.
Brown, J.D., Kharytonchyk, S., Chaudry, I., Iyer, A.S., Carter, H., Becker, G., Desai, Y., Glang, L., Choi, S.H., Singh, K., Lopresti, M.W., Orellana, M., Rodriguez, T., Oboh, U., Hijji, J., Ghinger, F.G., Stewart, K., Francis, D., Edwards, B., Chen, P., Case, D.A., Telesnitsky, A., Summers, M.F.(2020) Science 368: 413-417
- PubMed: 32327595
- DOI: https://doi.org/10.1126/science.aaz7959
- Primary Citation of Related Structures:
6VU1, 6VVJ - PubMed Abstract:
Heterogeneous transcriptional start site usage by HIV-1 produces 5'-capped RNAs beginning with one, two, or three 5'-guanosines ( Cap 1G, Cap 2G, or Cap 3G, respectively) that are either selected for packaging as genomes ( Cap 1G) or retained in cells as translatable messenger RNAs (mRNAs) ( Cap 2G and Cap 3G). To understand how 5'-guanosine number influences fate, we probed the structures of capped HIV-1 leader RNAs by deuterium-edited nuclear magnetic resonance. The Cap 1G transcript adopts a dimeric multihairpin structure that sequesters the cap, inhibits interactions with eukaryotic translation initiation factor 4E, and resists decapping. The Cap 2G and Cap 3G transcripts adopt an alternate structure with an elongated central helix, exposed splice donor residues, and an accessible cap. Extensive remodeling, achieved at the energetic cost of a G-C base pair, explains how a single 5'-guanosine modifies the function of a ~9-kilobase HIV-1 transcript.
Organizational Affiliation:
Howard Hughes Medical Institute and Department of Chemistry and Biochemistry, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
