has part U2-type spliceosomal complex U2 snRNP U6 snRNP U2-type catalytic step 2 spliceosome mah major catalytic step 2 spliceosome mammalian U2-type spliceosomal complex C 2009-07-30T12:00:35Z GO:0071007 GT-AG catalytic step 2 spliceosome mammalian U2-type spliceosomal complex C1 yeast U2-type spliceosomal complex A2-2 A spliceosomal complex that contains the U2, U5 and U6 snRNPs bound to a splicing intermediate in which the first catalytic cleavage of the 5' splice site has occurred. The precise subunit composition differs significantly from that of the catalytic step 1, or activated, spliceosome, and includes many proteins in addition to those found in the U2, U5 and U6 snRNPs. cellular_component catalytic step 2 spliceosome