PBX1
Domain
The homeobox is required for PBX1 nuclear localization and for transcriptional activation of NFIL3.
Function
Transcription factor which binds the DNA sequence 5'-TGATTGAT-3' as part of a heterodimer with HOX proteins such as HOXA1, HOXA5, HOXB7 and HOXB8 (PubMed:9191052). Binds to the DNA sequence 5'-TGATTGAC-3' in complex with a nuclear factor which is not a class I HOX protein (PubMed:9191052). Has also been shown to bind the DNA sequence 5'-ATCAATCAA-3' cooperatively with HOXA5, HOXB7, HOXB8, HOXC8 and HOXD4 (PubMed:7791786, PubMed:8327485). Acts as a transcriptional activator of PF4 in complex with MEIS1 (PubMed:12609849). Also activates transcription of SOX3 in complex with MEIS1 by binding to the 5'-TGATTGAC-3' consensus sequence (By similarity). In natural killer cells, binds to the NFIL3 promoter and acts as a transcriptional activator of NFIL3, promoting natural killer cell development (By similarity). Plays a role in the cAMP-dependent regulation of CYP17A1 gene expression via its cAMP-regulatory sequence (CRS1) (By similarity). Probably in complex with MEIS2, involved in transcriptional regulation by KLF4 (PubMed:21746878). Acts as a transcriptional activator of NKX2-5 and a transcriptional repressor of CDKN2B (By similarity). Together with NKX2-5, required for spleen development through a mechanism that involves CDKN2B repression (By similarity).
Isoform PBX1b
As part of a PDX1MEIS2B complex in pancreatic acinar cells, is involved in the transcriptional activation of the ELA1 enhancer; the complex binds to the enhancer B element and cooperates with the transcription factor 1 complex (PTF1) bound to the enhancer A element.
Involvement in disease
Congenital anomalies of kidney and urinary tract syndrome with or without hearing loss, abnormal ears, or developmental delay
CAKUTHED
An autosomal dominant disorder characterized by variable congenital anomalies of the kidney and urinary tract, sometimes resulting in renal dysfunction or failure, dysmorphic facial features, and abnormalities of the outer ear. Most patients have hearing loss, and some may have global developmental delay.
None
The disease is caused by variants affecting the gene represented in this entry.
A chromosomal aberration involving PBX1 is a cause of pre-B-cell acute lymphoblastic leukemia (B-ALL). Translocation t(1;19)(q23;p13.3) with TCF3. TCF3-PBX1 transforms cells by constitutively activating transcription of genes regulated by PBX1 or by other members of the PBX protein family. TCF3-PBX1 binds the DNA sequence 5'-ATCAATCAA-3'.
Sequence Similarities
Belongs to the TALE/PBX homeobox family.
Tissue Specificity
Expressed in the kidney. Expressed in the endothelial cells of the glomeruli and interstitium (at protein level) (PubMed:28270404). Expressed in all tissues except in cells of the B and T lineage. Expressed strongly in kidney and brain (PubMed:28270404).
Cellular localization
- Nucleus
Alternative names
PRL, PBX1, Pre-B-cell leukemia transcription factor 1, Homeobox protein PBX1, Homeobox protein PRL