U- and A-rich regions upstream of carmovirus CP ORFs. The nucleotide density of the region 250 nt upstream to 50 nt downstream of the CP initiation site for 15 carmoviruses was determined using a 50-nt sliding window analysis. “CP” denotes the CP start codon. An A-rich region (shaded blue) was observed immediately upstream of the CP start site, whereas a U-rich region (shaded purple) was observed further upstream. An A/U-rich region is marked by overlapping blue and purple shading for SYMMV and MNSV. Viruses (accession numbers) used for this analysis were as follows: TCV (NC_003821), Cardamine chlorotic fleck virus (CCFV) (NC_001600), PFBV (NC_005286), HCRSV (NC_003608), Calibrachoa mottle virus (CbMV) (NC_021926), Carnation mottle virus (CarMV) (NC_001265), Japanese iris necrotic ring virus (JINRV) (NC_002187), Angelonia flower break virus (AFBV) (NC_007733), Saguaro cactus virus (SCV) (NC_001780), Honeysuckle ringspot virus (HNRSV) (NC_014967), Soybean yellow mottle mosaic virus (SYMMV) (NC_011643), Melon necrotic spot virus (MNSV) (NC_001504), Cowpea mottle virus (CMeV) (NC_003535), Nootka lupine vein clearing virus (NLVCV) (NC_009017), and Trailing lespedeza virus 1 (TLV1) (NC_015227).