Arch Virol (2003) 148: 165–175 DOI 10.1007/s00705-002-0909-0 Complete nucleotide sequence of spring beauty latent virus, a bromovirus infectious to Arabidopsis thaliana ∗ Brief Report K. Fujisaki, F. Hagihara, M. Kaido, K. Mise, and T. Okuno Laboratory of Plant Pathology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan Received May 20, 2002; accepted August 20, 2002 Published online November 4, 2002 c  Springer-Verlag 2002 Summary. Spring beauty latent virus (SBLV), a bromovirus, systemically and efficiently infected Arabidopsis thaliana, whereas the well-studied bromoviruses brome mosaic virus (BMV) and cowpea chlorotic mottle virus (CCMV) did not infect and poorly infected A. thaliana, respectively. We constructed biologically active cDNA clones of SBLV genomic RNAs and determined their complete nucleotide sequences. Interestingly, SBLV RNA3 contains both the box B motif in the intercistronic region, as does BMV, and the subgenomic promoter-like sequence in the 5 ′ noncoding region, as does CCMV. Sequence comparisons of SBLV, BMV, CCMV, and broad bean mottle virus demonstrated that SBLV is closely related to BMV and CCMV. ∗ Systemic infection by plant viruses is established via multiple steps. At each step, several viral and host factors are involved in virus multiplication. To elucidate the mechanism of viral infections of plants, many viral factors have been examined, but host factors have not been identified in sufficient detail. The complete genome of Arabidopsis thaliana has been sequenced [8, 9], and this plant species has been used as a model in many studies including the analysis of plant–microbe interactions [14, 15]. Bromoviruses are icosahedral plant viruses, the genomes of which are positive- sense tripartite RNA molecules designated RNA1, RNA2, and RNA3 [25]. ∗ Nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AB080598, AB080599 and AB080600.