Phospho-Serine/Threonine Rabbit mAb (S-4180-7)

Phospho-Serine/Threonine refers to the process of phosphorylation modification occurring on serine (Ser) or threonine (Thr) residues of proteins, which is one of the most common and important post-translational modifications in eukaryotic cells. This modification is catalyzed by serine/threonine protein kinases, which transfer the γ-phosphate group of ATP to the hydroxyl group of Ser/Thr residues, forming a phosphoester bond; dephosphorylation is carried out by specific serine/threonine protein phosphatases, and together they maintain the dynamic equilibrium of phosphorylation status. In mammalian cells, approximately 80% of the kinome consists of serine/threonine kinases, and more than 90% of the phosphoproteome is composed of phosphoserine and phosphothreonine, with a relative abundance ratio of approximately 1800:200:1 (pS:pT:pY). Phosphorylation modification can regulate protein catalytic activity by altering protein conformation, and can also form signaling complexes by recruiting partner proteins containing specific phosphorylation-recognition domains (such as 14-3-3, WW, FHA, etc.), thereby playing a central role in processes such as signal transduction, cell cycle, metabolic regulation, apoptosis, and stress response. Abnormalities in this modification are closely associated with various diseases; for example, phosphorylation of AKT at Thr308/Ser473 sites is associated with tumor drug resistance, and hyperphosphorylation of Tau protein is one of the hallmark pathological features of Alzheimer's disease.