SFPQ (PTB-associated splicing factor)

1p34.3

DNA- and RNA binding protein; pre-mRNA splicing factor; binds specifically to intronic polypyrimidine tracts.
Role in transcription and RNA splicing: SFPQ, often called PSF, is a coactivator of Fox proteins, which bind the RNA element UGCAUG and regulate alternative pre-mRNA splicing. SFPQ and NONO are part of a large complex with all the snRNPs. SFPQ is phosphorylated by GSK3, which prevents SFPQ from binding PTPRC (CD45 antigen) pre-mRNA. The association of HNRNPL and SFPQ drives the change in PTPRC (CD45) splicing (CD45 undergoes alternative splicing in response to T-cell activation).
DNA damage: DNA double-strand breaks are repaired via nonhomologous DNA end joining and homologous recombination. The SFPQ/NONO heterodimer enhances DNA strand break rejoining. SFPQ has homologous recombination and non-homologous end joining activities. SFPQ is associated with the RAD51 protein complex.
Role in transcriptional regulation: SFPQ and PTK6 (protein tyrosine kinase 6, also called BRK) play a role downstream of the EGF receptor (EGFR). SFPQ and NONO form complexes with the androgen receptor (AR) and modulate its transcriptional activity (Huret, 2011).

ABL1 (v-abl Abelson murine leukemia viral oncogene homolog 1)

9q34.12

ABL1, when localized in the nucleus, induces apoptosis after DNA damage. Cytoplasmic ABL1 has a possible function in adhesion signalling (Turhan, 2008).