ESCRT-independent budding


The ESCRT-independent budding is not well understood, and has been essentially described for Influenza . Several viruses that use an ESCRT independent budding also encode for a viroporin that may be involved in budding.
Viroporin would act for budding by inducing local membrane depolarization. This could reduce repultion between contacting monolayers, and therefore enhance the contacts that are required for fission.

Enveloped viruses using viroporin for budding:

Family Virus Viroporin Budding location Evidence
Arteriviridae Equine arteritis virus E? ERGIC ?
Coronaviridae Human SARS coronavirus E ERGIC
Flaviviridae Hepatitis C virus P7 ERGIC
Flaviviridae Dengue virus M ERGIC
Orthomyxoviridae Influenza virus M2 Plasma membrane
Pneumovirinae Human respiratory syncytial virus SH? Plasma membrane ?
Togaviridae Sindbis virus 6K? Endosomes, plasma membrane


Non-Enveloped viruses using viroporin for budding:

Family Virus Viroporin Budding location Evidence
Polyomaviridae SV40 VP4 Endoplasmic reticulum
Rotaviridae Human rotavirus Nsp4 Endoplasmic reticulum