OBO ID: GO:0071017

Term Name:	U12-type catalytic step 1 spliceosome		Search Ontology:
Synonyms:	AT-AC catalytic step 1 spliceosome mammalian U12-type spliceosomal complex B* mammalian U12-type spliceosomal complex B2 minor catalytic step 1 spliceosome U12-type activated spliceosome yeast U12-type spliceosomal complex A1
Definition:	A spliceosomal complex that is formed by the displacement of the U11 and U4atac snRNPs from the precatalytic spliceosome; the U12, U5 and U6atac snRNPs remain associated with the mRNA. This complex, sometimes called the activated spliceosome, is the catalytically active form of the spliceosome, and includes many proteins in addition to those found in the U12, and U5 and U6atac snRNPs. (3)
References:
Ontology:	GO: Cellular Component    QuickGO    AmiGO