Table 1.

Phosphopeptides identified for the protein Mad1.

Best ion score a	Sequence	Precursor ion charge	Phosphosite position	Phosphosite reported previouslyb	Putative upstream kinase(s)c
27.71	SLNNFISQR	2+	S16	Yes	Mps1, Plk1
34.77	IQELQASQEAR	2+	S214	Yes	Mps1, Plk1, ATM kinase
33.02	DLEQKLSLQEQDAAIVK	3+	S233	No
41.78	LSLQEQDAAIVK	2+	S233	No
46.69	AILGSYDSELTPAEYSPQLTR	3+	S428	Yes	Mps1, Cdk1
54.81	AILGSYDSELTPAEYSPQLTR	2+	S428	Yes	Mps1, Cdk1
83.7	SQSSSAEQSFLFSR	2+	S484	No
56.79	SQSSSAEQSFLFSR	2+	S485	No
68.94	SQSSSAEQSFLFSR	2+	S486	No
72.63	SQSSSAEQSFLFSR	2+	S490	Yes	Mps1, Plk1
31.74	SQSSSAEQSFLFSREEADTLR	3+	S494	No
28.07	EEADTLR	2+	T500	No
21.74	LKVEELEGERSR	3+	S513	Yes	Mps1, (Plk1)
25.55	LKVEELEGERSR	2+	S513	Yes	Mps1, (Plk1)
24.27	VEELEGERSR	2+	S513	Yes	Mps1, (Plk1)
22.61	ALQGDYDQSR	2+	S538	No	Mps1, (Plk1)
25.25	LREDHSQLQAECER	3+	S562	Yes	Mps1, (Plk1)

^aBest ion score determined by the Mascot search engine. A detailed list of all identified MS/MS-spectra is shown in Tables S20 and S21.

^bAdopted from www.phosphosite.org (20.05.14).

^cPredicted consensus motif for Mps1, Plk1, Cdk1 and ATM/ATR kinase.