has part U12-type spliceosomal complex U6atac snRNP U12 snRNP catalytic step 2 spliceosome U12-type catalytic step 2 spliceosome mah yeast U12-type spliceosomal complex A2-2 mammalian U12-type spliceosomal complex C1 AT-AC catalytic step 2 spliceosome GO:0071018 minor catalytic step 2 spliceosome 2009-07-30T12:00:35Z A spliceosomal complex that contains the U12, U5 and U6atac 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 U12, U5 and U6atac snRNPs. cellular_component mammalian U12-type spliceosomal complex C