go_id,ontology,go_term,term_definition,evidence
GO:0000243,CC,"commitment complex","A spliceosomal complex that is formed by association of the U1 snRNP with the 5' splice site of an unspliced intron in an RNA transcript.",IBA
GO:0000387,BP,"spliceosomal snRNP assembly","The aggregation, arrangement and bonding together of one or more snRNA and multiple protein components to form a ribonucleoprotein complex that is involved in formation of the spliceosome.",IDA
GO:0000395,BP,"mRNA 5'-splice site recognition","Recognition of the intron 5'-splice site by components of the assembling spliceosome.",IDA
GO:0000398,BP,"mRNA splicing, via spliceosome","The joining together of exons from one or more primary transcripts of messenger RNA (mRNA) and the excision of intron sequences, via a spliceosomal mechanism, so that mRNA consisting only of the joined exons is produced.",IGI
GO:0003727,MF,"single-stranded RNA binding","Interacting selectively and non-covalently with single-stranded RNA.",IBA
GO:0003729,MF,"mRNA binding","Interacting selectively and non-covalently with messenger RNA (mRNA), an intermediate molecule between DNA and protein. mRNA includes UTR and coding sequences, but does not contain introns.",IBA
GO:0005515,MF,"protein binding","Interacting selectively and non-covalently with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules).",IPI
GO:0005654,CC,nucleoplasm,"That part of the nuclear content other than the chromosomes or the nucleolus.",IDA
GO:0005685,CC,"U1 snRNP","A ribonucleoprotein complex that contains small nuclear RNA U1.",IBA
GO:0008270,MF,"zinc ion binding","Interacting selectively and non-covalently with zinc (Zn) ions.",IEA
GO:0015030,CC,"Cajal body","A class of nuclear body, first seen after silver staining by Ramon y Cajal in 1903, enriched in small nuclear ribonucleoproteins, and certain general RNA polymerase II transcription factors; ultrastructurally, they appear as a tangle of coiled, electron-dense threads roughly 0.5 micrometers in diameter; involved in aspects of snRNP biogenesis; the protein coilin serves as a marker for Cajal bodies. Some argue that Cajal bodies are the sites for preassembly of transcriptosomes, unitary particles involved in transcription and processing of RNA.",IEA
GO:0030627,MF,"pre-mRNA 5'-splice site binding","Interacting selectively and non-covalently with the pre-mRNA 5' splice site sequence.",IBA
GO:0042803,MF,"protein homodimerization activity","Interacting selectively and non-covalently with an identical protein to form a homodimer.",IEA
GO:0044822,MF,"poly(A) RNA binding","Interacting non-covalently with a poly(A) RNA, a RNA molecule which has a tail of adenine bases.",IDA
GO:0071004,CC,"U2-type prespliceosome","A spliceosomal complex that is formed by association of the 5' splice site with the U1 snRNP, while the branch point sequence is recognized by the U2 snRNP. The prespliceosome includes many proteins in addition to those found in the U1 and U2 snRNPs. Commitment to a given pair of 5' and 3' splice sites occurs at the time of prespliceosome formation.",IBA
GO:0071010,CC,prespliceosome,"A spliceosomal complex that is formed by association of the 5' splice site and the branch point sequence with specific snRNPs. The prespliceosome includes many proteins in addition to those found in the bound snRNPs. Commitment to a given pair of 5' and 3' splice sites occurs at the time of prespliceosome formation. Prespliceosome complexes are not active for splicing, but are instead an early step in the assembly of a spliceosomal complex.",IBA
GO:1990446,MF,"U1 snRNP binding","Interacting selectively and non-covalently with any part of a U1 small nuclear ribonucleoprotein particle.",IEA