Table 1.

Identification of yeast U1 snRNP proteins

Mr (app.) (kDa)	Mr (calc.) (kDa)	Peptides sequenced	Protein name	Corresponding gene	Accession number
69	75.1	7	Prp39p	PRP39	L29224L29224
69	69.1	3	Prp40p	PRP40	P33203P33203
37	34.4	3	Mud1p	MUD1	P32605P32605
34	34.4	2	Snp1p	SNP1	X59986X59986
31	27.0	3	U1-C	SCL8003 17	U17243U17243
18	16.3	3	Sm D1	SMD1	Q02260Q02260
15	12.1	5	Sm D2	SCL9328 3	U17245U17245
12	10.4	1*	Sm E	SC55020 15	U55020U55020
11	9.6	2	Sm F	SCL9705 11	U25842U25842
10	11.2	4	Sm D3	SMD3	P43321P43321
9	8.5	2	Sm G	SNP2	P40204P40204

^*The identity of this peptide was further ascertained by methylation and ¹⁸O-labeling.