Artículos de revistas
Structural biology of coronavirus ion channels
Fecha
2021Registro en:
2059-7983
Autor
Barrantes, Francisco José
Institución
Resumen
Abstract: Viral infection compromises specific organelles of the cell and readdresses its
functional resources to satisfy the needs of the invading body. Around 70% of
the coronavirus positive-sense single-stranded RNA encodes proteins involved
in replication, and these viruses essentially take over the biosynthetic and
transport mechanisms to ensure the efficient replication of their genome and
trafficking of their virions. Some coronaviruses encode genes for ion-channel
proteins – the envelope protein E (orf4a), orf3a and orf8 – which they
successfully employ to take control of the endoplasmic reticulum–Golgi
complex intermediate compartment or ERGIC. The E protein, which is one
of the four structural proteins of SARS-CoV-2 and other coronaviruses,
assembles its transmembrane protomers into homopentameric channels with
mild cationic selectivity. Orf3a forms homodimers and homotetramers. Both
carry a PDZ-binding domain, lending them the versatility to interact with more
than 400 target proteins in infected host cells. Orf8 is a very short 29-amino-acid
single-passage transmembrane peptide that forms cation-selective channels
when assembled in lipid bilayers. This review addresses the contribution of
biophysical and structural biology approaches that unravel different facets of
coronavirus ion channels, their effects on the cellular machinery of infected cells
and some structure–functional correlations with ion channels of higher
organisms.