Table 1.

Cleavage sites displaying the canonical specificity of M^pro identified by TAILS analysis. Six peptides spanning the canonical Gln at P1 site were identified by TAILS.

Cleavage site (P5-P5’)a	Identified peptide (P1’-Pn’)	Gene name	UniProt Accession	Protein name
GAEIQ↓DGRFN	DGRFNLFKVQQGR	FIP1	Q9D824–4	Pre-mRNA 3'-end-processing factor FIP1
GETEQ↓KRIRK	KRIRKKKAKKR	CA131	Q8CIL4	Uncharacterized protein C1orf131 homolog
SSPSQ↓SGDTQ	SGDTQTFAQKLQLR	GOGA4	Q91VW5	Golgin subfamily A member 4
QLNSQ↓LFVGG	LFVGGKSSRQKGFFGCIR	CTP5C	Q0V8T7	Contactin-associated protein like 5–3
KRSQQ↓EDDQE	EDDQEFFEDR	FBX43	Q8CDI2	F-box only protein 43
SSSVQ↓IDPPL	IDPPLSSWKDLRTFKQR	COSA1	Q2UY11	Collagen alpha-1(XXVIII) chain

^aSince TAILS approach targets prime-side peptides, non-prime side positions (i.e. P5 to P1) were bioinformatically inferred from peptide identifications, after database searches using the MS data.