Recombinant Human PIAS1 protein

**Background of PIAS1 Recombinant Protein**

PIAS1 (Protein Inhibitor of Activated STAT1) is a member of the PIAS family of proteins, initially identified as a suppressor of STAT (Signal Transducer and Activator of Transcription)-mediated gene transcription. It plays multifaceted roles in cellular processes, including transcriptional regulation, post-translational modifications (e.g., SUMOylation), and signal transduction pathways. Structurally, PIAS1 contains a SAP domain (involved in chromatin binding), a PINIT motif (critical for subcellular localization), a SUMO-interacting motif (SIM), and a RING-finger-like zinc-binding domain essential for its E3 SUMO ligase activity.

PIAS1 regulates diverse pathways such as JAK-STAT, NF-κB, and p53. modulating inflammation, immune responses, apoptosis, and DNA repair. It acts as a co-regulator by either enhancing or repressing transcription factor activity, depending on cellular context. Dysregulation of PIAS1 is implicated in diseases like cancer, autoimmune disorders, and neurodegenerative conditions. For instance, it can promote tumorigenesis by stabilizing oncoproteins or inhibit metastasis by suppressing invasive signaling.

Recombinant PIAS1 protein is engineered using expression systems (e.g., *E. coli* or mammalian cells) to study its biochemical functions, interactions, and therapeutic potential. Purified PIAS1 is utilized in *in vitro* assays to explore SUMOylation mechanisms, screen small-molecule inhibitors, or analyze DNA-protein binding. Its recombinant form retains enzymatic activity and structural integrity, enabling research into its role in cellular homeostasis and disease pathogenesis.

Overall, PIAS1 recombinant protein serves as a critical tool for deciphering its regulatory networks and developing targeted therapies, bridging molecular biology with translational medicine.