obsolete first U2-type spliceosomal transesterification activity
Ontology
molecular_function
Synonyms
first U2-type spliceosomal transesterification activity, lariat formation, 5'-splice site cleavage
Alternate IDs
None
Definition
OBSOLETE. Catalysis of the first transesterification reaction of U2-type spliceosomal mRNA splicing. The intron branch site adenosine is the nucleophile attacking the 5' splice site, resulting in cleavage at this position. In cis splicing, this is the step that forms a lariat structure of the intron RNA, which is still joined to the 3' exon. The catalytic site is thought to be formed by U6 and/or U2 snRNA, and/or associated proteins.
Source:
GOC:krc,
ISBN:0879695897
Comment
This term was made obsolete because the activities used in the U2- and U12-type complexes are the same. The cellular component ontology should (and does) represent the two different complexes, but the molecular function ontology should not.
Link
to all genes and gene products annotated to obsolete first U2-type spliceosomal transesterification activity (excluding "regulates").
Link
to all direct and indirect annotations
to obsolete first U2-type spliceosomal transesterification activity (excluding "regulates").
Link
to all direct and indirect annotations download (limited to first 10,000)
for obsolete first U2-type spliceosomal transesterification activity (excluding "regulates").