Splicing factor, proline- and glutamine-rich (SFPQ)

DNA- and RNA binding protein, involved in a number of nuclear processes. Essential pre-mRNA splicing factor required early in spliceosome formation and for splicing catalytic step II, probably as a heteromer with NONO.

Involved in regulation of signal-induced alternative splicing. During splicing of PTPRC/CD45, a phosphorylated form is sequestered by THRAP3 in the pre-mRNA in resting T-cells; T-cell activation and subsequent reduced phosphorylation is proposed to lead to discharge from THRAP3 allowing binding to pre-mRNA splicing regulatotry elements which represses exon inclusion.