ANNOTATED SEQUENCE RECORD Complete genomic sequence analysis reveals a novel fabavirus infecting cucurbits in China Shu-Wei Dong • Hai-Ying Xiang • Qiao-Xia Shang • Da-Wei Li • Jia-Lin Yu • Cheng-Gui Han Received: 24 September 2011 / Accepted: 18 November 2011 / Published online: 21 December 2011 Ó Springer-Verlag 2011 Abstract The complete genome sequence of a cucurbit-infecting fabavirus was determined. Sequence analysis revealed that it had a genomic organization typical of fabaviruses, with genome segment sizes of 5870 nt (RNA-1) and 3294 nt (RNA-2). It shared CP and Pro-Pol amino acid sequence identities of 52.0–58.9% with those of reported fabaviruses. ELISA and western blots gave no cross-reactions between this cucurbit virus and broad bean wilt viruses 1 and 2. Based on molecular and serological criteria for species demarcation in the genus Fabavirus, the virus represents a distinct species, for which the species name Cucurbit mild mosaic virus (CuMMV) is proposed. Fabaviruses, which are aphid-transmitted in a non-persis- tent manner, can infect a wide range of hosts including dicotyledonous and some families of monocotyledonous plants [8]. The RNA genome consists of two RNAs (5.9–6.3 kb [RNA-1] and 3.1–4.5 kb [RNA-2]) that are linear, single-stranded and 3 0 polyadenylated, have a positive polarity, and encode polyprotein precursors. The polyprotein translated from RNA-1 is processed into five mature proteins: cofactor required for the proteinase (Co-Pro), putative helicase (Hel), proteinase (Pro), genome - linked protein (VPg) and RNA-dependent RNA poly- merase (Pol). The polyprotein encoded by RNA-2 is pro- cessed into movement protein (MP) and two coat proteins (LCP and SCP) [8]. The genus Fabavirus currently com- prises four species: Broad bean wilt virus 1 (BBWV-1), Broad bean wilt virus 2 (BBWV-2), Lamium mild mosaic virus (LMMV), and Gentian mosaic virus (GeMV), whereas patchouli mild mosaic virus (PatMMV) is con- sidered a strain of BBWV-2, and mikania micrantha mosaic virus (MMMV) is considered an isolate of GeMV [8]. The genomic sequences of BBWV-1, BBWV-2, GeMV, and MMMV have been determined [3–5, 10]. Members of the subfamily Comovirinae that have been reported to infect cucurbit crops include one comovirus (squash mosaic virus [SqMV]), five nepoviruses (arabis mosaic virus [AMV], artichoke yellow ringspot virus [AYRV], tobacco ringspot virus [TRSV], tobacco black ring virus [TBRV] and tomato ringspot virus [ToRSV]), and one tentative nepovirus (Melon mild mottle virus S.-W. Dong and H.-Y. Xiang contributed equally to this work. Electronic supplementary material The online version of this article (doi:10.1007/s00705-011-1202-x) contains supplementary material, which is available to authorized users. S.-W. Dong Á H.-Y. Xiang Á D.-W. Li Á J.-L. Yu Á C.-G. Han State Key Laboratory for Agro-biotechnology and Ministry of Agriculture Key Laboratory for Plant Pathology, China Agricultural University, Beijing 100193, P. R. China e-mail: dongsw05@gmail.com D.-W. Li e-mail: lidw@cau.edu.cn J.-L. Yu e-mail: yjl@cau.edu.cn H.-Y. Xiang Yunnan Academy of Tobacco Science, Kunming 650106, P. R. China e-mail: xhy236@yahoo.com.cn Q.-X. Shang Department of Plant Science and Technology, Beijing University of Agriculture, Beijing 102206, P. R. China e-mail: shangqiaoxia@bac.edu.cn C.-G. Han (&) Department of Plant Pathology, China Agricultural University, Beijing 100193, P. R. China e-mail: hanchenggui@cau.edu.cn 123 Arch Virol (2012) 157:597–600 DOI 10.1007/s00705-011-1202-x