Fig. 2
A. Modified carboxyl-termini of ORF8 predicted to be encoded by an insertion of a 5′-UTR segment in SARS-related β-coronaviruses of Rhinolophus bats from China. For SARS-related bat β-CoVs (BatSARSCoV Rf1/2004 and Bat CoV 273/2005 are subgroup 2b; [7]), all inserted terminal sequences were the same. The nucleotide sequence of the inserted 5′-UTR segment differed from that of SARS-CoV-2 by two nucleotides: a C to U change (underlined) which translates into an amino acid change (serine [S] to phenylalanine [F]), and a U to A (underlined) which introduces a stop codon. B. Modified carboxyl termini of ORF7b protein predicted to be encoded by an insertion of a 5′-UTR segment in SARS-CoV-2. The two isolates with predicted modified ORF-7 proteins are QXH28554 (USA/Alabama, 2021/04/14), and QSV08409 (USA/California; 2021/02/26); the latter has a truncated ORF7b and the former a truncated ORF8. Color codes and abbreviations are as in Fig. 1. C. Secondary structures of ORF7b and ORF7bx RNAs. Color scheme is as in Fig. 1B. An HIV-like attenuation sequence [57] is also highlighted