Table 1.

Mass spectrometry identification of C complex proteins

LC-MS/MS analysis of C complex spliceosomes. Listed is the number of unique peptides identified in either untrimmed or exon-trimmed C complex spliceosomes analyzed in this work. Columns from left to right are the Entrez gene ID number, human protein name, S. cerevisiae homolog, molecular weight in kDa, C complex analyzed previously ¹³, C complex analyzed in this work (C^b), exon-trimmed C complex (Tr), and 1M salt resistant “core” C complex as reported in ¹². An * denotes proteins detected in a separate mass spectrometry analysis of a much lower abundance sample of exon-trimmed complexes, but not in the run reported here.

Entrez ID	Protein	S.c.	MW	Ca	Cb	Tr	core
snRNP core protein
6628	SmB/B′	Smb1p	24	•	9	1	•
6632	SmD1	Smd1p	13	•	6	3	•
6633	SmD2	Smd2p	14	•	15	3	•
6634	SmD3	Smd3p	14	•	7	1	•
6635	SmE1	Sme1p	11	•	8	3
6636	SmF1	Smf1p	10	•	1		•
6637	SmG1	Smg1p	9	•	4		•
U2 snRNP associated proteins
6627	U2-A′	Lea1p	28	•	16	2	•
6629	U2-B″	Msl1p	26	•	9	2	•
51639	p14	Snu17p	15		1	1	•
23451	SF3b155	Hsh155p	146	•	4	9	•
10992	SF3b145	Cus1p	98	•	8	3	•
23450	SF3b130	Rse1p	136	•	12	28	•
84844	SF3b14b	Rds3p	12		3	1	•
10291	SF3a120	Prp21p	89	•	6	8	•
1665	hPRP43	Prp43p	93	•	3	6	•
U5 snRNP proteins
10594	PRP8	Prp8p	274	•	88	28	•
23020	U5-200kD	Brr2p	206	•	63	32	•
9343	U5-116kD	Snu114p	109	•	50	38	•
9416	U5-100kD	Prp28p	96	•	3	3
9410	U5-40kD		39	•	19	5	•
Second step factors
9785	PRP16	Prp16p	140	•	3	2	•
51362	PRP17	Prp17p	66	•	23	5	•
10569	SLU7	Slu7p	68	•	16	3	•
1659	PRP22	Prp22p	139	•	40	10
PRP19 complex associated
27339	PRP19	Prp19p	55	•	26	14	•
22938	SKIP	Prp45p	62	•	20	8	•
988	CDC5	Cef1p	92	•	42	14	•
51340	CRN	Clf1p	99	•	89	44	•
57461	ISY1	Isy1p	33	•	23	3	•
5356	PRL1	Prp46	58	•	14	10	•
55696	RBM22	Ecm2p	47	•	10	6	•
10450	PPIE		33	•	16	3	•
3312	HSP73	Ssa1p	71	•	19	10
9716	IBP-160		171	•	73	24	•
51645	PPIL1		18	•	9	2	•
25949	GCIP-IP	Syf2p	29	•	19	1	•
10286	BCAS2	Snt309p	26		10	1	•
Proteins present in B and C complexes
57703	KIAA1604	Cwc22p	57	•	24	10	•
8446	DDX16	Prp2	119	•	2	4
23759	PPIL2		59	•		3
84811	BUD13	Bud13p	71		1	2	•
10283	SDCCAG10	Cwc27p	54	•		2
Proteins unique to C complexes
60625	DHX35		79	•	10	5	•
51428	DDX41		70	•	20	5
58509	C19orf29		99	•	11	4
23398	PPWD1		74	•	24	6
55094	GPATCH1		103	•	6	1
51503	HSPC148	Cwc15p	27	•	7	3*	•
8896	G10	Cwc14p	17		13	5*	•
53938	PPIL3b		18	•	8	1*
Proteins in C complex not found after exon trimming
151903	CCDC12		19		8
51759	HSPC220		34	•	3
84292	MORG1		34	•	4
8220	DGSI		53	•	5
9130	XAP-5		40	•	8
51070	NOSIP		33	•	5
63932	NKAP		26	•	6
26017	FAM32A		13		10
11100	HNRPUL1		96		3
EJC/mRNP proteins
9775	eIF4a-III		47	•	14	2	•
4116	Magoh		17	•	8	1	•
9939	Y14		20	•	3		•
6428	SRp20		19	•	3
hnRNP proteins
10949	hnRNP A0		31		5
3178	hnRNP A1		39	•	10	3
3181	hnRNPA2/B2		41	•	8	2
220988	hnRNP A3		40	•	3
3183	hnRNP C		32	•	17	8	•
27316	hnRNP G		47	•	4
4670	hnRNP M		78	•	5
10236	hnRNP R		71	•	8	2
22913	RALY		32	•	9		•
Pre-mRNA binding proteins
22916	CBP20	Cbc2p	18	•	1		•
4686	CBP80	Cbc1p	93	•	7		•
3306	HSP70-2	Ssa2	70	•	4		•
23517	SKIV2L2	Mtr4	118	•		3
8106	PAB2		33	•	3	1
3608	NF45		45	•	3	1
1655	p68	Dbp2p	69	•		1
9584	RNPC2		59	•	2
8531	CSDA		40	•	2
9782	MAT3		95	•	1
4904	YB-1		36	•	3