Êtes-vous un étudiant de l'EPFL à la recherche d'un projet de semestre?
Travaillez avec nous sur des projets en science des données et en visualisation, et déployez votre projet sous forme d'application sur Graph Search.
Concept
Protéine enveloppe du Coronavirus
Résumé
The envelope (E) protein is the smallest and least well-characterized of the four major structural proteins found in coronavirus virions. It is an integral membrane protein less than 110 amino acid residues long; in SARS-CoV-2, the causative agent of Covid-19, the E protein is 75 residues long. Although it is not necessarily essential for viral replication, absence of the E protein may produce abnormally assembled viral capsids or reduced replication. E is a multifunctional protein and, in addition to its role as a structural protein in the viral capsid, it is thought to be involved in viral assembly, likely functions as a viroporin, and is involved in viral pathogenesis.
The E protein consists of a short hydrophilic N-terminal region, a hydrophobic helical transmembrane domain, and a somewhat hydrophilic C-terminal region. In SARS-CoV and SARS-CoV-2, the C-terminal region contains a PDZ-binding motif (PBM). This feature appears to be conserved only in the alpha and beta coronavirus groups, but not gamma. In the beta and gamma groups, a conserved proline residue is found in the C-terminal region likely involved in targeting the protein to the Golgi.
The transmembrane helices of the E proteins of SARS-CoV and SARS-CoV-2 can oligomerize and have been shown in vitro to form pentameric structures with central pores that serve as cation-selective ion channels. Both viruses' E protein pentamers have been structurally characterized by nuclear magnetic resonance spectroscopy.
The membrane topology of the E protein has been studied in a number of coronaviruses with inconsistent results; the protein's orientation in the membrane may be variable. The balance of evidence suggests the most common orientation has the C-terminus oriented toward the cytoplasm. Studies of SARS-CoV-2 E protein are consistent with this orientation.
In some, but not all, coronaviruses, the E protein is post-translationally modified by palmitoylation on conserved cysteine residues.
Source officielle
À propos de ce résultat
Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.