Notes on Family: Flaviviridae

enveloped spheres
enveloped spheres

Contents

General Description

This family is characterised by enveloped spherical virions and a single component of single-stranded RNA, which does not have a polyA tail and which encodes a single polyprotein that is subsequently processed into a number of structural and non-structural proteins.

Morphology

Virions enveloped and spherical 40-60 nm in diameter.

Genomen

Monopartite positive sense single-stranded RNA of about 9.5-12.5kb and without a 3'-polyA tail. There is a single polyprotein that is subsequently processed into a number of structural and non-structural proteins. The coat protein and two or three membrane-associated proteins occur in the N-terminal portion of the polyprotein.

Genera in the Family

  • Flavivirus: genome 10-12kb, encoding three structural proteins; infecting vertebrates and invertebrates
  • Pegivirus: genome <10kb, encoding two structural proteins; infecting vertebrates
  • Pestivirus: genome >12kb, encoding four structural proteins
  • Hepacivirus: genome <10kb, encoding three structural proteins; infecting humans