Enables C2H2 zinc finger domain binding activity and protein N-terminus binding activity. Involved in mRNA splicing, via spliceosome. Located in Cajal body and nuclear speck. Part of U2-type catalytic step 2 spliceosome and U2-type precatalytic spliceosome. Biomarker of Parkinson's disease. [provided by Alliance of Genome Resources, Apr 2022]