Table 1. Tryptic peptides identified from U9-ORF via LC-MS/MS.

Table includes charge states for each peptide (z), SrchName (indicating gel region from Figure S4a), measured precursor mass accuracy (Δ Error, in ppm), SEQUEST XCorr values, and Unique ΔCorr values for each peptide identified. “.” after arginine and lysine residues indicate the sites of tryptic cleavage. “C#” indicates carboxyamidomethylation on cysteine.

Peptide	z	SrchName	PPM	XCorr	Uniq. ΔCorr
R.FC#EFFK.I	2	ORF_U1	−0.24	1.99	0
R.FC#EFFK.I	2	ORF_U1	−0.23	1.85	0
R.FC#EFFK.I	2	ORF_U1	−0.13	1.95	0
R.FC#EFFK.I	2	ORF_U1	−0.01	2.05	0
R.FC#EFFK.I	2	ORF_U1	−0.01	2.30	0
R.FC#EFFK.I	2	ORF_U1	−0.01	1.99	0
R.FC#EFFK.I	2	ORF_U1	0.25	1.84	0
R.FC#EFFK.I	2	ORF_U1	0.33	1.93	0
R.FC#EFFK.I	2	ORF_U1	0.39	1.92	0
K.IFLYC#PFFNRK.H	3	ORF_U1	0.53	2.86	0.81
K.IFLYC#PFFNRK.H	3	ORF_U1	0.53	3.21	0.85
K.IFLYC#PFFNRK.H	3	ORF_U1	0.54	3.43	0.84
K.IFLYC#PFFNR.K	2	ORF_U1	1.28	2.52	0.86
K.IFLYC#PFFNR.K	2	ORF_U1	1.78	2.50	0.88
K.IFLYC#PFFNR.K	2	ORF_U1	1.78	2.36	0.85
K.IFLYC#PFFNR.K	2	ORF_U2	−0.55	2.55	0.96