E3 SUMO-protein ligase PIAS4; PIASy; protein inhibitor of activated STAT protein 4; protein inhibitor of activated STAT protein gamma; PIAS-gamma (PIAS4, PIASG)
Jump to navigation
Jump to search
Function
- E3-type small ubiquitin-like modifier (SUMO) ligase
- stabilizes interaction between UBE2I & substrate
- SUMO-tethering factor
- role in transcriptional coregulation in cellular pathways
- STAT pathway
- p53 pathway
- Wnt pathway
- steroid hormone signaling pathway
- role in gene silencing
- promotes PARK7 sumoylation
- in Wnt signaling
- represses LEF1
- enhances TCF4 transcriptional activities through promoting their sumoylations
- protein modification; protein sumoylation
- sumoylated
- Lys-35 is the main site of sumoylation
- sumoylation is required for TCF4 sumoylation & transcriptional activation
- represses LEF1 transcriptional activity
- SUMO1 is the preferred conjugate
- interacts with AR, AXIN1, GATA2, LEF1, TP53 & STAT1 (IFNG-induced)
- preferentially binds AT-rich DNA sequences, known as matrix attachment regions or scaffold attachment regions (putative)
- interacts with TICAM1
- interacts with KLF8; the interaction results in SUMO ligation & repression of KLF8 transcriptional activity & of its cell cycle progression into G1 phase
Structure
- the LXXLL motif is a coregulator signature essential for transcriptional corepression
- belongs to the PIAS family
- contains 1 PINIT domain
- contains 1 SAP domain
- contains 1 SP-RING-type Zn+2 finger
Compartment
- nucleus, PML body
- colocalizes with SUMO1 & TCF7L2/TCF4 & LEF1 in a subset of PML (promyelocytic leukemia) nuclear bodies
Expression
- highly expressed in testis
- lower expression in spleen, prostate, ovary, colon & peripheral blood leukocytes