General Background : MYO-INOSITOL "myo-Inositol"-containing phospholipids play an important role in the control of cellular functions, being part of the intracellular signal transductions pathways from various regulators, including hormones, neurotransmitters, growth factors, and serum . When these regulators interact with their receptors in cell membranes, they induce the hydrolysis of certain : Phosphoinositides "phosphoinositides" to produce second messenger molecules. : 1-PHOSPHATIDYL-1D-MYO-INOSITOL-5-PHOSPHA "phosphatidylinositol 5-phosphate" was discovered in 1997 in mammalian fibroblasts as a source for : PHOSPHATIDYL-MYO-INOSITOL-45-BISPHOSPHA "phosphatidylinositol 4,5-bisphosphate" , and is still considered the least-characterized member of the phosphoinositol family. It is believed to play a role as a regulator of membrane trafficking . The best established pathway for the synthesis of : 1-PHOSPHATIDYL-1D-MYO-INOSITOL-5-PHOSPHA "phosphatidylinositol 5-phosphate" is the dephosphorylation of : 1-PHOSPHATIDYL-1D-MYO-INOSITOL-35-BISPH, catalyzed by a number of myotubularin-related phosphatases, such as : HS02045 and : HS08920 . Another source for the compound is the removal of the 4-phosphate group from : PHOSPHATIDYL-MYO-INOSITOL-45-BISPHOSPHA by either of two dedicated phsphatases, encoded by : HS14553 and : HS15363 . It has been shown that : 1-PHOSPHATIDYL-1D-MYO-INOSITOL-5-PHOSPHA "phosphatidylinositol 5-phosphate" is phosphorylated to : PHOSPHATIDYL-MYO-INOSITOL-45-BISPHOSPHA by : HS07693-MONOMER, encoded by : HS07693 . However, the concentration of : 1-PHOSPHATIDYL-1D-MYO-INOSITOL-5-PHOSPHA "phosphatidylinositol 5-phosphate" in the cell is very low (about 2% of : CPD-1108 "phosphatidylinositol 4-phosphate"), and thus it is unlikely that its main role is as a source of : PHOSPHATIDYL-MYO-INOSITOL-45-BISPHOSPHA biosynthesis. However, the exact role of this compound in the cell is still unknown

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PIP4K2A , PLCB2 , PLCB3 , PLCD1 , PLCG1 , PLCG2 , MTMR3 , PLCH1 , PLCE1 , TMEM216 , PIP4P2 , MTMR14 , PIP4K2C , PLCD4 , PLCZ1 , PIP4P1 , PLCD3 ,