Related Experiment Video
Updated: Jun 22, 2026
09:45
In Vitro SUMOylation Assay to Study SUMO E3 Ligase Activity
Published on: January 29, 2018
PIAS proteins: pleiotropic interactors associated with SUMO
Miia M Rytinki1, Sanna Kaikkonen, Petri Pehkonen
1Institute of Biomedicine/Medical Biochemistry, University of Kuopio, Kuopio, Finland.
Cellular and Molecular Life Sciences : CMLS
|June 16, 2009
Summary
Protein inhibitors of activated STAT (PIAS) proteins regulate diverse transcription factors beyond STATs. PIAS proteins mediate cellular regulation through SUMO-linked protein assemblies, not solely as SUMO E3 ligases.
Area of Science:
- Molecular Biology
- Cellular Regulation
Background:
- Protein inhibitors of activated STAT (PIAS) proteins interact with and regulate various proteins, particularly transcription factors.
- While PIAS proteins can act as SUMO E3 ligases, their functions extend beyond this role.
- PIAS proteins possess domains for noncovalent interaction with SUMO proteins and DNA.
Purpose of the Study:
- To provide an overview of cellular regulation by PIAS proteins.
- To elucidate the mechanisms underlying PIAS protein functions.
- To propose a model for PIAS-mediated cellular regulation.
Main Methods:
- Literature review and synthesis of existing research on PIAS proteins.
- Analysis of PIAS protein interaction partners and regulatory functions.
- Examination of the structural domains and their roles in protein-protein and protein-DNA interactions.
Main Results:
- PIAS proteins (PIAS1, -2, -3, -4) regulate a wide array of transcription factors, not exclusively STATs.
- PIAS protein functions are often independent of their SUMO E3 ligase activity.
- SUMO-interacting motifs and other domains are crucial for PIAS protein interactions and functions.
Conclusions:
- PIAS proteins mediate cellular regulation through diverse mechanisms, including SUMO-linked protein assemblies.
- Their ability to form noncovalent interactions is key to their regulatory roles.
- PIAS proteins are versatile regulators involved in complex cellular processes.
Related Concept Videos
01:09Cytoskeletal Linker Proteins - Plakins
Plakins are large proteins with binding domains for microtubules, microfilaments, intermediate filaments, and membrane-associated protein complexes at cell junctions. Plakin functions are evolutionarily conserved and are primarily involved in organizing the different components of the cytoskeleton by crosslinking them to each other and connecting them to the cell-matrix and cell adhesion complexes. They are also known to interact with signal transducers, serve as scaffolds for signaling...
01:42Phosphoinositides and PIPs
Phosphoinositides are a group of phospholipids containing a glycerol backbone with two fatty acid chains and a phosphate attached to a myoinositol sugar ring. The inositol head group extends into the cytoplasm, where it is modified by adding phosphate groups to form phosphatidylinositol phosphates or PIPs.
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
02:57piRNA - Piwi-interacting RNAs
PIWI-interacting RNAs, or piRNAs, are the most abundant short non-coding RNAs. More than 20,000 genes have been found in humans that code for piRNAs while only 2000 genes have been found for miRNAs. piRNAs can act at the transcriptional and post-transcriptional levels and have a vital role in silencing transposable elements present in germ cells. They are also involved in epigenetic silencing and activation. Previously, they were thought to function only in germ cells but new evidence suggests...
01:20The JAK-STAT Signaling Pathway
Several cytokine receptors have tightly bound Janus kinase or JAK proteins attached at their cytosolic tail. Small signaling molecules such as cytokines, growth hormones, or prolactins bind to the cytokine receptors and initiate their dimerization. The dimerization brings the cytosolic JAKs together that trans-phosphorylate and activates each other. The activated JAKs now phosphorylate cytosolic tails of the cytokine receptors, which serve as binding sites for adaptor proteins such as SH2...
02:04Protein-protein Interfaces
Many proteins form complexes to carry out their functions, making protein-protein interactions (PPIs) essential for an organism's survival. Most PPIs are stabilized by numerous weak noncovalent chemical forces. The physical shape of the interfaces determines the way two proteins interact. Many globular proteins have closely-matching shapes on their surfaces, which form a large number of weak bonds. Additionally, many PPIs occur between two helices or between a surface cleft and a polypeptide...
01:42Microtubule Associated Proteins (MAPs)
Microtubule function and architecture are regulated by an array of specialized proteins called microtubule-associated proteins or MAPs. These proteins are widespread across different organisms and have conserved protein motifs, like the multi-TOG domain for tubulin binding found in the CLASP family of MAPs. Some MAPs are lineage-specific based on their conserved domains. Their functions depend upon the cytoskeletal architecture and cell type they are located within. In-plant cells, a specific...