PSIP1
Function
Transcriptional coactivator involved in neuroepithelial stem cell differentiation and neurogenesis. Involved in particular in lens epithelial cell gene regulation and stress responses. May play an important role in lens epithelial to fiber cell terminal differentiation. May play a protective role during stress-induced apoptosis. Isoform 2 is a more general and stronger transcriptional coactivator. Isoform 2 may also act as an adapter to coordinate pre-mRNA splicing. Cellular cofactor for lentiviral integration.
Involvement in disease
A chromosomal aberration involving PSIP1 is associated with pediatric acute myeloid leukemia (AML) with intermediate characteristics between M2-M3 French-American-British (FAB) subtypes. Translocation t(9;11)(p22;p15) with NUP98. The chimeric transcript is an in-frame fusion of NUP98 exon 8 to PSIP1 exon 4.
Post-translational modifications
Citrullinated by PADI4.
Sequence Similarities
Belongs to the HDGF family.
Tissue Specificity
Widely expressed. Expressed at high level in the thymus. Expressed in fetal and adult brain. Expressed in neurons, but not astrocytes. Markedly elevated in fetal as compared to adult brain. In the adult brain, expressed in the subventricular zone (SVZ), in hippocampus, and undetectable elsewhere. In the fetal brain, expressed in the germinal neuroepithelium and cortical plate regions.
Cellular localization
- Nucleus
- Remains chromatin-associated throughout the cell cycle.
Alternative names
DFS70, LEDGF, PSIP2, PSIP1, PC4 and SFRS1-interacting protein, CLL-associated antigen KW-7, Dense fine speckles 70 kDa protein, Lens epithelium-derived growth factor, Transcriptional coactivator p75/p52, DFS 70