An Absolutely Conserved Tryptophan in the Stem of the Envelope Protein E of Flaviviruses Is Essential for the Formation of Stable Particles.

ABSTRACT: The major envelope protein E of flaviviruses contains an ectodomain that is connected to the transmembrane domain by the so-called "stem" region. In mature flavivirus particles, the stem is composed of two or three mostly amphipathic α-helices and a conserved sequence element (CS) with an undefined role in the viral life cycle. A tryptophan is the only residue within this region which is not only conserved in all vector-borne flaviviruses, but also in the group with no known vector. We investigated the importance of this residue in different stages of the viral life cycle by a mutagenesis-based approach using tick-borne encephalitis virus (TBEV). Replacing W421 by alanine or histidine strongly reduced the release of infectious virions and their thermostability, whereas fusion-related entry

SUBMITTER: Medits I 

PROVIDER: S-EPMC8473212 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature