Note - Blast analyses are based on comparisons of the phosphosites and the bordering four amino acids on each side of these phosphosites.

Phosphosite
Human Protein:	USP21
Human P-Site:	S35
P-Site Sequence:	PFAPRARSKERRNPA
UniProt:	Q9UK80
Intern. Prot. ID:	IPI00007262

Protein Phosphosite Match	Human Protein Short Name	Human UniProt. ID	Phosphosite Number	Sequence	% Identity / # AA	Target Size kDa
Phosphosite 0:	USP21	Q9UK80	S35	PFAPRARSKERRNPA	100 / 9 AA	63
Phosphosite 1:	SFRS15	O95104	S478	RHSPRSRSQERRDRE	77 / 9 AA	126
Phosphosite 2:	EXOSC10	Q01780	S217	KPLPQALSKERRERP	77 / 9 AA	101
Phosphosite 3:	RBM39	Q14498	S76	RERKRSRSKERRRSR	87 / 8 AA	59
Phosphosite 4:	MAGEL2	Q9UJ55	S12	FYRPQGSSKERRTSS	66 / 9 AA	59
Phosphosite 5:	PPIG	Q13427	S618	TPPGRSRSKDRRRRR	75 / 8 AA	89
Phosphosite 6:	HIRIP3	Q9BW71	S263	DWKPRTRSNGRRKSA	66 / 9 AA	62
Phosphosite 7:	CACNA1E	Q15878	S2086	GGRERGRSKERKHLL	75 / 8 AA	262
Phosphosite 8:	SAPAP1	O14490	S184	RYGKRSKSKERRAEP	75 / 8 AA	109
Phosphosite 9:	PRPF38B	Q5VTL8	S389	RERSRERSKEQRSRG	66 / 9 AA	64
Phosphosite 10:	RP1L1	Q8IWN7	S527	RLTPRARSEEGASSD	85 / 7 AA	261
Phosphosite 11:	DLGAP4	Q9Y2H0	S184	GKGRRAKSKERAKAG	85 / 7 AA	108
Phosphosite 12:	PRPF38B	Q5VTL8	S503	KSRKRSRSKERSHKR	85 / 7 AA	64
Phosphosite 13:	PRPF4B	Q13523	S309	SKDRRSRSKERKSKR	75 / 8 AA	117
Phosphosite 14:	VPS16	Q9H269	S276	VWCSRPRSKERAVVV	85 / 7 AA	95
Phosphosite 15:	RSRC2	Q7L4I2	S130	RSHSRSRSRERRHRS	66 / 9 AA	51
Phosphosite 16:	SFRS4	Q08170	S304	KSKSRSRSQERRVEE	66 / 9 AA	57
Phosphosite 17:	U2AF1	Q01081	S199	KHRSRSRSRERRSRS	66 / 9 AA	28
Phosphosite 18:	MAGI1	Q96QZ7	S1435	TDRRRARSPERRRER	87 / 8 AA	165
Phosphosite 19:	CACNA1B	Q00975	S2111	RRQERGRSQERRQPS	75 / 8 AA	262
Phosphosite 20:	RDBP	P18615	S187	ASPPRSRSRDRSHER	62 / 8 AA	43