A previously proposed consensus secondary structure model of the internal portion of the 5\'-untranslated region of the enterovirus and rhinovirus genomes encompassing the cis-acting translational control element was extended and detailed on the basis of comparative sequence data and biochemical analysis. Using this model as a reference, numerous pairs of apparently single-stranded noncontiguous nucleotide stretches with a potential to form inter-domain tertiary bonds were shown to be conserved among the respective segments of all the known enterovirus and rhinovirus RNAs. It is suggested that at least some of these inter-domain bonds may actually exist, resulting in a compact, quasi-globular, perhaps "two-lobe" folding of the translational control element. Such an organization should have important functional implications.