Notes on Genus: Turncurtovirus

twinned icosahedra
twinned icosahedra

Type member: Turnip curly top virus


General Description

This is one of 7 genera in the family Geminiviridae. Its single member most closely resembles members of the genus Curtovirus but it is phylogenetically distinct and the genome encodes 6 rather than 7 proteins.


Virions are geminate (twinned) icosahedra, not enveloped, 38 nm long and 22 nm in diameter. 22 capsomeres per nucleocapsid.


Monopartite, closed circular, single stranded DNA, about 2970 nucleotides long.

Genus Genomic Organization

There are two open reading frames (ORFs) in the positive (virion) sense and four in the negative (complementary) sense.

Type Member Genomic Organization

ORFsense product
V1+32 kDa Coat protein
V2+15 kDa Movement protein
C1-42 kDa Replication initiator protein
C2-16 kDa Transciption activator protein (TrAP)
C3-17 kDa Replication enhancer protein
C4-10 kDa Symptom determinant