Potato virus X: A global potato-infecting virus and type member of the Potexvirus genus

Abstract

Taxonomy: Potato virus X is the type-member of the plant-infecting Potexvirus genus in the family Alphaflexiviridae. Physical properties: Potato virus X (PVX) virions are flexuous filaments 460–480 nm in length. Virions are 13 nm in diameter and have a helical pitch of 3.4 nm. The genome is approximately 6.4 kb with a 5′ cap and 3′ poly(A) terminus. PVX contains five open reading frames, four of which are essential for cell-to-cell and systemic movement. One protein encodes the viral replicase. Cellular inclusions, known as X-bodies, occur near the nucleus of virus-infected cells. Hosts: The primary host is potato, but it infects a wide range of dicots. Diagnostic hosts include Datura stramonium and Nicotiana tabacum. PVX is transmitted in nature by mechanical contact. Useful website: https://talk.ictvonline.org/ictv-reports/ictv_online_report/positive-sense-rna-viruses/w/alphaflexiviridae/1330/genus-potexvirus.