Pleckstrin (PLEK)

Pleckstrin is the **major protein kinase C substrate in platelets** and also occurs in leukocytes and various immune cells[1][2][3][4]. It contains two pleckstrin homology (PH) domains at its N- and C- termini, separated by a central dishevelled/Egl-10/pleckstrin (DEP) domain, and is approximately 47 kDa in size. Upon phosphorylation by protein kinase C, pleckstrin translocates to the plasma membrane, where it binds phosphoinositides and associates with integrins and the Rac GTPase to coordinate **actin cytoskeleton reorganization, membrane remodeling, and cell spreading**—processes critical for **platelet activation and aggregation** as well as immune functions like phagocytosis and cytokine secretion[1][2]. While pleckstrin is essential in hematopoietic and immune cell signaling, no direct drugs are reported to target pleckstrin, nor is it established as a classical drug target protein (like receptor, enzyme, or transporter)[3]. Phosphorylated pleckstrin serves as a **biomarker for platelet activation**, but no major safety or therapeutic challenges have been documented regarding direct pleckstrin inhibition. Its paralog, pleckstrin-2 (PLEK2), is more widely studied in cancer progression, but this is distinct from PLEK1 (pleckstrin)[1][2].

Other names

Platelet 47 kDa proteinP47Pleckstrin-1PLEK1PLEK