Work

A retroviral RNA kissing complex containing only two G⋅C base pairs

Year: 2000

Type: article

Abstract: The dimerization of viral RNA through noncovalent interactions at their 5' ends is a key step in the life cycle of retroviruses. In Moloney murine leukemia virus, three stem-loops are important in this process. One is a self-complementary tetraloop (H1), but the other two stem-loops (H2, H3) contain highly conserved GACG tetraloops that are not self-complementary sequences. Using two-dimensional NMR, we determined the structure of the H3 stem-loop. Surprisingly, it forms a stable, homodimeric kissing complex through only two intermolecular G small middle dotC base pairs. Cross-strand interactions of the adenines adjacent to the intermolecular G small middle dotC base pairs, plus unusual strong electrostatic interactions around the base pairs, contribute to the unexpected stability. This structure shows how even stem-loops without self-complementary sequences can facilitate the intermolecular recognition between two identical RNAs, and thus initiate dimerization and encapsidation of retroviral RNAs.

Source: Proceedings of the National Academy of Sciences

DOI: 10.1073/pnas.170283697

Authors: Chul-Hyun Kim, Ignacio Tinoco

Institutions: Lawrence Berkeley National Laboratory, University of California, Berkeley

Language: English

Topic: RNA and protein synthesis mechanisms

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funders: National Science Foundation, U.S. Department of Energy, National Institutes of Health, National Institute of General Medical Sciences

Awards: G3676917958, STRUCTURE/FUNCTION OF NUCLEIC ACIDS, Structure and Function of Nucleic Acids