Display Settings:


Send to:

Choose Destination

3-phosphoinositide degradation

|FRAME: Phosphoinositides "Phosphoinositides"| play a key role in signal transduction in the eukaryotic cell, transmitting signals from the cell surface to modulate intracellular processes. The 3-phosphoinositides, which contain the monophosphate |FRAME: CPD-177 "phosphatidylinositol 3-phosphate"|, the bisphosphate |FRAME: 1-PHOSPHATIDYL-1D-MYO-INOSITOL-34-BISPH "phosphatidylinositol 3,4-bisphosphate"| and the trisphosphate |FRAME: PHOSPHATIDYLINOSITOL-345-TRIPHOSPHATE "phosphatidylinositol 3,4,5-trisphosphate"|, are particularly important in signaling cascades that influence a wide variety of cellular functions. These compounds are.generated by the action of several phosphatidylinositol 3-kinases (PI 3-kinases), as described in the pathway |FRAME: PWY-6352|. The levels of specific phosphoinositide pools are regulated by intricate networks of enzymes and proteins that govern the rates of phosphoinositide synthesis, transport, and degradation. |FRAME: PHOSPHATIDYLINOSITOL-345-TRIPHOSPHATE "Phosphatidylinositol 3,4,5-trisphosphate"| is a transient plasma membrane signal, and is rapidly hydrolyzed by a 5-phosphatase reaction to |FRAME: 1-PHOSPHATIDYL-1D-MYO-INOSITOL-34-BISPH "phosphatidylinositol 3,4-bisphosphate"| or by a 3-phosphatase reaction to |FRAME: PHOSPHATIDYL-MYO-INOSITOL-45-BISPHOSPHA "phosphatidylinositol 4,5-bisphosphate"|. The 5-phosphatase reaction is catalyzed by several inositol polyphosphate 5-phosphatases that belong to groups type II (|FRAME: HS05898|, |FRAME: HS08354|, |FRAME: HS01279|, |FRAME: HS04546|, |FRAME: HS05626|, |FRAME: HS12255|), type III (|FRAME: HS09233|, |FRAME: HS09849|) and type IV (|FRAME: HS09270|). The 3-phosphatase reaction is catayzed by |FRAME: HS10404-MONOMER| |CITS:[8399352][12018404]|. The importance of this reaction is made clear by the fact that mutations in this gene are found in a high percentage of human tumors, and particularly in glioblastoma, melanoma, and prostate and endometrial carcinomas |CITS:[12543774][12379854][12209607][12203792][12203362][12119278][12085208]|. The bisphosphate products can also be degraded. |FRAME: 1-PHOSPHATIDYL-1D-MYO-INOSITOL-34-BISPH "Phosphatidylinositol 3,4-bisphosphate"|, an important second messenger on its own, is considered a more sustained signal, and lasts for up to 60 min before being hydrolyzed to form |FRAME: CPD-177| by the inositol polyphosphate 4-phosphatases (|FRAME: HS00551| and |FRAME: HS03227|) |CITS: [9417038][12101241]|. It can also be hydrolyzed by |FRAME: HS10404| to form |FRAME: CPD-1108|. |FRAME: PHOSPHATIDYL-MYO-INOSITOL-45-BISPHOSPHA "phosphatidylinositol 4,5-bisphosphate"|, is hydrolyzed by either 4-phosphatases (|FRAME: HS14553| and |FRAME: HS15363|) or the same 5-phosphatases listed above, resulting in |FRAME: 1-PHOSPHATIDYL-1D-MYO-INOSITOL-5-PHOSPHA| or |FRAME: CPD-1108|, respectively. Finally, each of the monophosphates has been shown to be degraded by a specific enzyme, resulting in the formation of |FRAME: L-1-phosphatidyl-inositols|, which is recycled back to the membrane.

from BIOCYC source record: META_PWY-6368
Type: pathway
Taxonomic scope
conserved biosystem

Supplemental Content

Recent activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...