EF-hand motif found in phosphoinositide phospholipase C delta 3 (PI-PLC-delta3)
PI-PLC-delta3, also termed 1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase delta-3 (PLCD3), phospholipase C-delta-3 (PLC-delta-3), is expressed abundantly in brain, skeletal muscle and heart. PI-PLC-delta3 gene expression is down-regulation by cAMP and calcium. PI-PLC-delta3 acts as anchoring of myosin VI on plasma membrane, and further modulates Myosin IV expression and microvilli formation in enterocytes. It negatively regulates RhoA expression, inhibits RhoA/Rho kinase signaling, and plays an essential role in normal neuronal migration by promoting neuronal outgrowth in the developing brain. Moreover, PI-PLC-delta3 is essential in trophoblasts for placental development. Simultaneous loss of PI-PLC-delta3 may cause placental vascular defects, leading to embryonic lethality. PI-PLC-delta3 contains a core set of domains, including an N-terminal pleckstrin homology (PH) domain, four atypical EF-hand motifs, a PLC catalytic core, and a single C-terminal C2 domain. The PLC catalytic core domain is a TIM barrel with two highly conserved regions (X and Y) split by a highly degenerate linker sequence. In addition, PI-PLC-delta3 possesses a classical leucine-rich nuclear export sequence (NES) located in the EF hand motifs, which may be responsible transporting PI-PLC-delta3 from the cell nucleus.
Jiyao W et al.(2023). "The conserved domain database in 2023.",