Overview
| Uniprot ID | Q8VIJ6 |
| Protein Name | Splicing factor, proline- and glutamine-rich |
| Gene Name | Sfpq |
| Organism | Mus musculus |
Kla Sites from experimental identification
| Position |
Flanking peptide |
| 200 |
GPGPGGPKGGKMPGG |
| 695 |
EEYEGPNKKPRF*** |
Function
DNA- and RNA binding protein, involved in several nuclear processes. Essential pre-mRNA splicing factor required early in spliceosome formation and for splicing catalytic step II, probably as a heteromer with NONO. Binds to pre-mRNA in spliceosome C complex, and specifically binds to intronic polypyrimidine tracts. Involved in regulation of signal-induced alternative splicing. During splicing of PTPRC/CD45, a phosphorylated form is sequestered by THRAP3 from the pre-mRNA in resting T-cells; T-cell activation and subsequent reduced phosphorylation is proposed to lead to release from THRAP3 allowing binding to pre-mRNA splicing regulatotry elements which represses exon inclusion. Interacts with U5 snRNA, probably by binding to a purine-rich sequence located on the 3' side of U5 snRNA stem 1b. May be involved in a pre-mRNA coupled splicing and polyadenylation process as component of a snRNP-free complex with SNRPA/U1A. The SFPQ-NONO heteromer associated with MATR3 may play a role in nuclear retention of defective RNAs. SFPQ may be involved in homologous DNA pairing; in vitro, promotes the invasion of ssDNA between a duplex DNA and produces a D-loop formation. The SFPQ-NONO heteromer may be involved in DNA unwinding by modulating the function of topoisomerase I/TOP1; in vitro, stimulates dissociation of TOP1 from DNA after cleavage and enhances its jumping between separate DNA helices. The SFPQ-NONO heteromer binds DNA. The SFPQ-NONO heteromer may be involved in DNA non-homologous end joining (NHEJ) required for double-strand break repair and V(D)J recombination and may stabilize paired DNA ends; in vitro, the complex strongly stimulates DNA end joining, binds directly to the DNA substrates and cooperates with the Ku70/G22P1-Ku80/XRCC5 (Ku) dimer to establish a functional preligation complex. SFPQ is involved in transcriptional regulation. Functions as a transcriptional activator (By similarity). Transcriptional repression is mediated by an interaction of SFPQ with SIN3A and subsequent recruitment of histone deacetylases (HDACs). The SFPQ-NONO-NR5A1 complex binds to the CYP17 promoter and regulates basal and cAMP-dependent transcriptional activity. SFPQ isoform Long binds to the DNA binding domains (DBD) of nuclear hormone receptors, like RXRA and probably THRA, and acts as a transcriptional corepressor in absence of hormone ligands. Binds the DNA sequence 5'-CTGAGTC-3' in the insulin-like growth factor response element (IGFRE) and inhibits IGF1-stimulated transcriptional activity (By similarity). Regulates the circadian clock by repressing the transcriptional activator activity of the CLOCK-BMAL1 heterodimer. Required for the transcriptional repression of circadian target genes, such as PER1, mediated by the large PER complex through histone deacetylation (PubMed:21680841, PubMed:22966205). Required for the assembly of nuclear speckles (By similarity). Plays a role in the regulation of DNA virus-mediated innate immune response by assembling into the HDP-RNP complex, a complex that serves as a platform for IRF3 phosphorylation and subsequent innate immune response activation through the cGAS-STING pathway (By similarity)
Protein Sequence
10
MSRDRFRSRG
20
GGGGGFHRRG
30
GGGGRGGLHD
40
FRSPPPGMGL
50
NQNRGPMGPG
60
PGGPKPPLPP
70
PPPHQQQQQP
80
PPQQPPPQQP
90
PPHQQPPPHQ
100
PPHQQPPPPP
110
QESKPVVPQG
120
PGSAPGVSSA
130
PPPAVSAPPA
140
NPPTTGAPPG
150
PGPTPTPPPA
160
VPSTAPGPPP
170
PSTPSSGVST
180
TPPQTGGPPP
190
PPAGGAGPGP
200
KPGPGPGGPK
210
GGKMPGGPKP
220
GGGPGMGAPG
230
GHPKPPHRGG
240
GEPRGGRQHH
250
APYHQQHHQG
260
PPPGGPGPRT
270
EEKISDSEGF
280
KANLSLLRRP
290
GEKTYTQRCR
300
LFVGNLPADI
310
TEDEFKRLFA
320
KYGEPGEVFI
330
NKGKGFGFIK
340
LESRALAEIA
350
KAELDDTPMR
360
GRQLRVRFAT
370
HAAALSVRNL
380
SPYVSNELLE
390
EAFSQFGPIE
400
RAVVIVDDRG
410
RSTGKGIVEF
420
ASKPAARKAF
430
ERCSEGVFLL
440
TTTPRPVIVE
450
PLEQLDDEDG
460
LPEKLAQKNP
470
MYQKERETPP
480
RFAQHGTFEY
490
EYSQRWKSLD
500
EMEKQQREQV
510
EKNMKDAKDK
520
LESEMEDAYH
530
EHQANLLRQD
540
LMRRQEELRR
550
MEELHSQEMQ
560
KRKEMQLRQE
570
EERRRREEEM
580
MIRQREMEEQ
590
MRRQREESYS
600
RMGYMDPRER
610
DMRMGGGGTM
620
NMGDPYGSGG
630
QKFPPLGGGG
640
GIGYEANPGV
650
PPATMSGSMM
660
GSDMRTERFG
670
QGGAGPVGGQ
680
GPRGMGPGTP
690
AGYGRGREEY
EGPNKKPRF
Gene Ontology
| Classification |
GO ID |
Description |
| Cellular Component |
GO:0000785 |
chromatin |
| Cellular Component |
GO:0005737 |
cytoplasm |
| Cellular Component |
GO:0030425 |
dendrite |
| Cellular Component |
GO:0016363 |
nuclear matrix |
| Cellular Component |
GO:0016607 |
nuclear speck |
| Cellular Component |
GO:0005654 |
nucleoplasm |
| Cellular Component |
GO:0005634 |
nucleus |
| Cellular Component |
GO:0042382 |
paraspeckles |
| Cellular Component |
GO:0090575 |
RNA polymerase II transcription regulator complex |
| Molecular Function |
GO:0003682 |
chromatin binding |
| Molecular Function |
GO:0003677 |
DNA binding |
| Molecular Function |
GO:0042826 |
histone deacetylase binding |
| Molecular Function |
GO:0042803 |
protein homodimerization activity |
| Molecular Function |
GO:0003723 |
RNA binding |
| Molecular Function |
GO:0000976 |
transcription cis-regulatory region binding |
| Biological Process |
GO:0002218 |
activation of innate immune response |
| Biological Process |
GO:0000380 |
alternative mRNA splicing, via spliceosome |
| Biological Process |
GO:0006338 |
chromatin remodeling |
| Biological Process |
GO:0051276 |
chromosome organization |
| Biological Process |
GO:0098963 |
dendritic transport of messenger ribonucleoprotein complex |
| Biological Process |
GO:0006974 |
DNA damage response |
| Biological Process |
GO:0006351 |
DNA-templated transcription |
| Biological Process |
GO:0000724 |
double-strand break repair via homologous recombination |
| Biological Process |
GO:0045087 |
innate immune response |
| Biological Process |
GO:0042754 |
negative regulation of circadian rhythm |
| Biological Process |
GO:0045892 |
negative regulation of DNA-templated transcription |
| Biological Process |
GO:0000122 |
negative regulation of transcription by RNA polymerase II |
| Biological Process |
GO:1902177 |
positive regulation of oxidative stress-induced intrinsic apoptotic signaling pathway |
| Biological Process |
GO:0045876 |
positive regulation of sister chromatid cohesion |
| Biological Process |
GO:0045944 |
positive regulation of transcription by RNA polymerase II |
| Biological Process |
GO:0051726 |
regulation of cell cycle |
| Biological Process |
GO:0042752 |
regulation of circadian rhythm |
| Biological Process |
GO:0006355 |
regulation of DNA-templated transcription |
| Biological Process |
GO:0048511 |
rhythmic process |
Reference
[1] Wu D, Tang Y, Li X, Xiong S, Zhang Z et al.. Characterization of protein lactylation in healthy and ischemic mouse hearts.. Front Cardiovasc Med 12:1644886. 2025. PMID: 41089239.