Secondary structure of the SARS-CoV-2 5′ UTR, with superimposed in vivo SHAPE reactivities from Manfredonia et al. [39]. Highly (red) and moderately (yellow) reactive residues from in vitro SHAPE (circles; Manfredonia et al. [39]), in vitro DMS (triangles; Manfredonia et al. [39]), in vivo SHAPE (squares; Huston et al. [36]) and in vivo DMS (pentagons; Lan et al. 2020) experiments are also indicated [36,37,39]. A higher reactivity indicates a higher propensity of bases to be single-stranded (for DMS), or structurally flexible (for SHAPE). Base-paired regions are color-coded according to the number of supporting chimeric reads from Ziv et al. [38]. The number of reads supporting the existence of SL8 was calculated by reanalyzing data from Ziv et al. [38] (GEO dataset: GSE154662).