Arch Virol (2001) 146: 2435–2441
Molecular evidence that the aphid-transmitted Tomato mild mottle
virus belongs to the Potyviridae family but not the Potyvirus genus
W. A. Monger
, N. J. Spence
, and G. D. Foster
School of Biological Sciences,University of Bristol,Bristol,U.K.
Horticulture Research International,Wellesbourne,Warwick,U.K.
Accepted August 6,2001
Summary. Molecular studies have been carried out on Tomato mild mottle virus
(TMMV) and 2322 nucleotides of the aphid-transmitted virus have been
sequenced. This translates to a 2187 nucleotide open reading frame and a 135
nucleotide untranslated region (UTR) followed by a poly A tail. The sequence
is consistent with the NIb and coat protein regions of a member of the Potyviri-
dae family of viruses. Sequence comparisons show this virus to have no close
relationship with any previously sequenced aphid-transmitted virus; the highest
identity was found with the whiteﬂy-transmitted Ipomoviruses. The vector of
transmission and the low level of sequence identity with other aphid-transmitted
viruses suggest TMMV does not belong to any existing genus of the Potyviridae
In 1990 a virus was discovered in the village of Bani-Hushaish in the central
highlands of the Republic of Yemen,and named Tomato mild mottle virus .
The virus was isolated from Lycopersicon esculentum (tomato) and two nearby
weeds Datura stramonium (jimson weed) and Solanum nigrum (black night-
shade). The virus was found to have properties consistent with a member of the
Potyviridae family. It had ﬂexuous particles of 719 nm in length and produced
cytoplasmic pinwheel inclusion bodies that were unusual,in that they were di-
chotomously branched ,a characteristic that has not been reported for any
other virus. Gel electrophoresis had estimated the size of the coat protein as ca.
41.5 kDa but serological work with antisera against potyviruses,carlaviruses and
GenBank accession number AF359575.