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:	Y297
P-Site Sequence:	YVPSFSGYSQQDAQE
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	Y297	YVPSFSGYSQQDAQE	100 / 9 AA	63
Phosphosite 1:	USP33	Q8TEY7	Y267	VNPTFRGYSQQDAQE	77 / 9 AA	107
Phosphosite 2:	USP8	P40818	S865	NDQFAGYSQQDSQEL	87 / 8 AA	128
Phosphosite 3:	USP33	Q8TEY7	S268	NPTFRGYSQQDAQEF	87 / 8 AA	107
Phosphosite 4:	USP44	Q9H0E7	Y419	LIPAFRGYAQQDAQE	66 / 9 AA	81
Phosphosite 5:	USP20	Q9Y2K6	Y227	VNPMFRGYAQQDTQE	75 / 8 AA	102
Phosphosite 6:	USP15	Q9Y4E8	Y376	FAPQFSGYQQQDCQE	87 / 8 AA	112
Phosphosite 7:	USP4	Q13107	Y389	FAPQFSGYQQQDSQE	87 / 8 AA	109
Phosphosite 8:	USP49	Q70CQ1	Y395	LIPAFRGYDQQDAQE	66 / 9 AA	79
Phosphosite 9:	USP3	Q9Y6I4	Y256	IMPNFRGYQQQDAHE	66 / 9 AA	59
Phosphosite 10:	E4BP4	Q16649	S253	NYMGNSFSGYSHSPP	85 / 7 AA	51
Phosphosite 11:	E4BP4	Q16649	Y255	MGNSFSGYSHSPPLL	85 / 7 AA	51
Phosphosite 12:	FH	P07954	Y251	LGQEFSGYVQQVKYA	85 / 7 AA	55
Phosphosite 13:	USP27X	A6NNY8	Y160	HARHLAGYRQQDAHE	62 / 8 AA	50
Phosphosite 14:	SYNPR	Q8TBG9	Y238	SYGSSSGYSQQASLG	87 / 8 AA	29
Phosphosite 15:	FUS	P35637	S39	PYGQQSYSGYSQSTD	85 / 7 AA	53
Phosphosite 16:	USP22	Q9UPT9	Y258	HARHLAGYEQQDAHE	62 / 8 AA	60
Phosphosite 17:	PRPS1	P60891	S10	NIKIFSGSSHQDLSQ	75 / 8 AA	35
Phosphosite 18:	PRPS1L1	P21108	S10	NIKIFSGSSHQDLSQ	75 / 8 AA	35
Phosphosite 19:	PRPS1	P60891	S11	IKIFSGSSHQDLSQK	75 / 8 AA	35
Phosphosite 20:	PRPS1L1	P21108	S11	IKIFSGSSHQDLSQK	75 / 8 AA	35