GO:0047395 glycerophosphoinositol glycerophosphodiesterase activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0047395 describes the enzymatic hydrolysis of glycerophosphoinositol into sn-glycerol 3-phosphate, myo-inositol and a proton.
• The reaction is a phosphodiesterase step that recycles inositol and glycerol phosphate from phosphoinositide turnover products.
• GDE1/MIR16 is a well-characterized mammalian enzyme with this activity and is regulated by G protein-coupled receptor stimulation.
• The activity is part of the broader phosphoinositidase C signaling network that controls calcium and lipid second messengers [4,7].
• Dysregulation of phosphoinositide signaling has been linked to cancer, neurodegeneration and metabolic disease [1,8].
• CRISPR knockout, point mutation, knock-in and overexpression models enable causal testing of this activity in cells and animals.
Description
Glycerophosphoinositol glycerophosphodiesterase activity (GO:0047395) is a molecular function that catalyzes the hydrolysis of 1-(sn-glycero-3-phospho)-1D-myo-inositol to sn-glycerol 3-phosphate, myo-inositol and a proton. This reaction sits at the intersection of phosphoinositide metabolism and cellular signaling, because glycerophosphoinositol is a water-soluble product released when phosphoinositidase C cleaves phosphatidylinositol 4,5-bisphosphate [4,7]. Researchers study this activity to understand how cells recycle inositol and glycerol phosphate after receptor-stimulated lipid turnover. The enzyme GDE1/MIR16 was shown to be a glycerophosphoinositol phosphodiesterase whose activity is regulated by stimulation of G protein-coupled receptors, linking the reaction directly to hormone and neurotransmitter signaling. Because phosphoinositidase C signaling is central to calcium oscillations and growth factor responses, the glycerophosphodiesterase step is relevant to a wide range of physiological and pathological contexts [2,8]. This article summarizes the definition, mechanism, key genes, disease links and experimental models for GO:0047395, with all factual claims supported by the verified literature listed at the end.
glycerophosphoinositol glycerophosphodiesterase activity At A Glance
| GO ID | GO:0047395 |
|---|---|
| GO term | glycerophosphoinositol glycerophosphodiesterase activity |
| Ontology | molecular_function |
| Synonym | 1-(sn-glycero-3-phospho)-1D-myo-inositol glycerophosphohydrolase activity; sn-glycero-3-phospho-1-inositol glycerophosphohydrolase activity; sn-glycero(3)phosphoinositol glycerophosphohydrolase activity |
| Major function | Hydrolysis of glycerophosphoinositol to sn-glycerol 3-phosphate, myo-inositol and H+ |
| Reaction | 1-(sn-glycero-3-phospho)-1D-myo-inositol + H2O = sn-glycerol 3-phosphate + myo-inositol + H+ |
| Representative enzyme | GDE1/MIR16 |
| Regulatory context | Stimulation of G protein-coupled receptors |
| Pathway context | Phosphoinositide turnover and phosphoinositidase C signaling |
What Is GO:0047395?
In simple terms, GO:0047395 is the activity of an enzyme that cuts glycerophosphoinositol into two reusable pieces plus a proton. The official definition states: Catalysis of the reaction: 1-(sn-glycero-3-phospho)-1D-myo-inositol + H2O = sn-glycerol 3-phosphate + myo-inositol + H+. This is a phosphodiesterase activity because it breaks a phosphodiester bond, releasing myo-inositol and sn-glycerol 3-phosphate. The synonyms include 1-(sn-glycero-3-phospho)-1D-myo-inositol glycerophosphohydrolase activity, sn-glycero-3-phospho-1-inositol glycerophosphohydrolase activity and sn-glycero(3)phosphoinositol glycerophosphohydrolase activity. The activity is classified under molecular_function in the Gene Ontology and is distinct from phospholipase C, which acts on membrane lipids rather than the water-soluble glycerophosphoinositol [4,7].
Why Is glycerophosphoinositol glycerophosphodiesterase activity Important in Cell Biology?
GO:0047395 is important because it completes the recycling of inositol and glycerol phosphate generated during phosphoinositide signaling, a process that controls calcium mobilization, growth factor responses and nuclear lipid signaling [2,4,8]. Without this activity, cells would accumulate glycerophosphoinositol and could not efficiently regenerate myo-inositol for new phosphoinositide synthesis. The enzyme GDE1/MIR16 provides a direct link between G protein-coupled receptor stimulation and glycerophosphoinositol hydrolysis, making the activity a node where extracellular signals are converted into lipid metabolite changes. Because phosphoinositidase C signaling is implicated in desensitization, calcium oscillations and cell growth, understanding GO:0047395 helps explain how cells terminate and recycle second-messenger lipids [4,7]. This has practical implications for cancer biology, neuroscience and metabolic research, where phosphoinositide pathways are frequently altered [1,8].
• Recycles myo-inositol and sn-glycerol 3-phosphate from phosphoinositide turnover products.
• Links G protein-coupled receptor stimulation to glycerophosphoinositol hydrolysis.
• Supports phosphoinositidase C signaling by removing the water-soluble glycerophosphoinositol product [4,7].
• Contributes to calcium signaling and oscillation mechanisms in excitable and non-excitable cells.
• Relevant to nuclear phosphoinositide signaling during growth factor stimulation.
• Provides a metabolic node for studying inositol depletion and glycerol phosphate flux.
• Potential target context in cancer and metabolic disease through phosphoinositide pathway dysregulation [1,8].
• Enables CRISPR-based causal tests of enzyme function in cell models.
Molecular Mechanism of glycerophosphoinositol glycerophosphodiesterase activity
Substrate recognition and binding
In simple terms: The enzyme first grabs the glycerophosphoinositol molecule.
Glycerophosphoinositol glycerophosphodiesterase activity acts on the water-soluble substrate 1-(sn-glycero-3-phospho)-1D-myo-inositol, which is produced during phosphoinositide turnover. The enzyme must recognize the glycero-3-phospho-inositol headgroup while discriminating it from intact membrane phospholipids, because phospholipase C acts on lipids rather than on this soluble product [4,7]. In mammalian cells, GDE1/MIR16 is a representative enzyme with this activity, and its substrate accessibility is influenced by receptor-driven changes in phosphoinositide metabolism.
Catalytic hydrolysis of the phosphodiester bond
In simple terms: The enzyme uses water to split the molecule into two reusable parts.
The catalytic step is a hydrolysis reaction in which water attacks the phosphodiester bond of glycerophosphoinositol, yielding sn-glycerol 3-phosphate, myo-inositol and a proton. This is a phosphodiesterase-type cleavage, distinct from the phospholipase C reaction that generates glycerophosphoinositol in the first place [4,7]. The reaction is defined by the GO term GO:0047395 and is classified as a molecular_function in the Gene Ontology.
Product release and inositol recycling
In simple terms: The products are released so the cell can reuse them.
After hydrolysis, myo-inositol and sn-glycerol 3-phosphate are released for downstream metabolic use. Myo-inositol can be reincorporated into phosphoinositide synthesis, while sn-glycerol 3-phosphate enters glycerol lipid and energy metabolism. This recycling role connects GO:0047395 to the broader phosphoinositidase C signaling network that controls calcium and lipid second messengers [4,7].
Regulation by G protein-coupled receptor signaling
In simple terms: The enzyme's activity is switched on by signals from the cell surface.
GDE1/MIR16 glycerophosphoinositol phosphodiesterase activity is regulated by stimulation of G protein-coupled receptors, meaning the reaction is coupled to extracellular signals. This places the activity downstream of receptor-phosphoinositidase C coupling, where multiple G proteins can influence lipid signaling. Receptor regulation of phosphoinositidase C provides the upstream context for glycerophosphoinositol production and subsequent hydrolysis.
Integration with calcium and nuclear signaling
In simple terms: The reaction is part of the same signaling system that controls calcium and cell growth.
Phosphoinositidase C signaling generates calcium oscillations and second messengers, and glycerophosphoinositol is a product of that pathway [2,4]. Nuclear phosphoinositidase C is activated during growth factor stimulation, indicating that phosphoinositide turnover and its recycling enzymes operate in nuclear signaling contexts as well. Therefore GO:0047395 is mechanistically embedded in calcium, growth factor and nuclear lipid signaling networks [2,8].
Key Genes Involved in GO:0047395 glycerophosphoinositol glycerophosphodiesterase activity
The following genes and proteins are directly or contextually linked to glycerophosphoinositol glycerophosphodiesterase activity (GO:0047395) and its phosphoinositide signaling network.
| Gene | Major Role | Research Relevance |
|---|---|---|
| GDE1 | Encodes a glycerophosphoinositol phosphodiesterase with GO:0047395 activity | Direct enzyme for functional studies of the GO term |
| MIR16 | Alternative name for the same protein as GDE1 | Used in receptor-stimulated glycerophosphoinositol hydrolysis assays |
| PLCB1 | Phosphoinositidase C that generates glycerophosphoinositol | Upstream enzyme producing the substrate [4,7] |
| PLCB2 | Phosphoinositidase C isoform in signaling | Context for receptor-phosphoinositidase C coupling |
| PLCB3 | Phosphoinositidase C isoform in signaling | Context for receptor-phosphoinositidase C coupling |
| PLCG1 | Phosphoinositidase C gamma involved in growth factor signaling | Links growth factor stimulation to phosphoinositide turnover |
| PLCG2 | Phosphoinositidase C gamma isoform | Context for receptor-regulated phosphoinositide signaling |
| GNAQ | G protein alpha subunit coupling receptors to phosphoinositidase C | Upstream regulator of glycerophosphoinositol production |
| GNA11 | G protein alpha subunit in phosphoinositidase C signaling | Upstream regulator context |
| GNAI1 | G protein alpha subunit modulating phosphoinositidase C | Multiple G-protein coupling context |
| GNAI2 | G protein alpha subunit modulating phosphoinositidase C | Multiple G-protein coupling context |
| GNAI3 | G protein alpha subunit modulating phosphoinositidase C | Multiple G-protein coupling context |
| GNAO1 | G protein alpha subunit in neuronal phosphoinositidase C signaling | Neuronal signaling context |
| GNAZ | G protein alpha subunit in phosphoinositidase C signaling | Receptor coupling context |
| ITPR1 | Inositol trisphosphate receptor mediating calcium release | Downstream calcium signaling readout |
| ITPR2 | Inositol trisphosphate receptor isoform | Calcium oscillation context |
| ITPR3 | Inositol trisphosphate receptor isoform | Calcium signaling context |
How Is glycerophosphoinositol glycerophosphodiesterase activity Regulated?
Glycerophosphoinositol glycerophosphodiesterase activity is regulated by stimulation of G protein-coupled receptors, as shown for GDE1/MIR16. This regulation is embedded in the receptor-phosphoinositidase C coupling system, where multiple G proteins can modulate lipid signaling. Receptor regulation of phosphoinositidase C controls the production of glycerophosphoinositol, the substrate for GO:0047395. In addition, phosphoinositidase C signaling is subject to desensitization, which can indirectly affect substrate availability for the glycerophosphodiesterase reaction. Nuclear phosphoinositidase C activity during growth factor stimulation suggests that regulation also occurs in nuclear signaling compartments.
glycerophosphoinositol glycerophosphodiesterase activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| GDE1 | Phosphoinositide signaling and receptor-regulated lipid metabolism | CRISPR knockout and overexpression in cell lines |
| PLCB1 | Calcium signaling and growth factor responses | Point mutation and knock-in models [4,7] |
| PLCG1 | Growth factor signaling and nuclear phosphoinositide turnover | Knockout and tagged knock-in |
| ITPR1 | Calcium oscillation and neuronal signaling | Knock-in and overexpression models |
| GNAQ | G protein-coupled receptor signaling | Point mutation and knockout models |
Cancer and growth factor signaling
Phosphoinositide signaling is frequently altered in cancer, and nuclear phosphoinositidase C is activated during growth factor stimulation, linking this pathway to cell growth control. Because GO:0047395 recycles glycerophosphoinositol produced by phosphoinositidase C, changes in this activity could influence lipid second-messenger balance in cancer cells [3,8]. The broader phosphoinositidase C network has been discussed in the context of cell signaling and disease, supporting a role for this activity in proliferative signaling [4,7].
Neurodegeneration and neuronal signaling
G protein-coupled receptor signaling and calcium oscillations are central to neuronal function, and phosphoinositidase C is a key node in these processes [2,7]. Glycerophosphoinositol glycerophosphodiesterase activity is regulated by G protein-coupled receptors, which are major drug targets in neurological and psychiatric disorders. Therefore, altered recycling of glycerophosphoinositol could affect neuronal calcium signaling and receptor desensitization [4,7].
Metabolic and inositol-related disorders
The reaction produces myo-inositol and sn-glycerol 3-phosphate, both of which are metabolites relevant to inositol and glycerol lipid metabolism. Defects in inositol recycling could influence phosphoinositide synthesis and membrane lipid homeostasis. This makes GO:0047395 a potential node for studying metabolic conditions linked to inositol depletion or altered lipid flux.
From glycerophosphoinositol glycerophosphodiesterase activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of GDE1 alter glycerophosphoinositol hydrolysis? | CRISPR knockout cell line |
| Does a catalytic-site mutation abolish GO:0047395 activity? | Point mutation knock-in |
| Where does the enzyme localize in cells? | Tagged knock-in with fluorescent tag |
| Does overexpression change inositol recycling? | Overexpression cell model |
| How does receptor stimulation regulate the activity? | Knockout plus receptor agonist treatment |
| Which G proteins couple to the pathway? | Knockout and point mutation of G protein subunits |
How to Study the glycerophosphoinositol glycerophosphodiesterase activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Enzymatic activity assay | Hydrolysis of glycerophosphoinositol to products | Direct measurement of GO:0047395 |
| CRISPR knockout | Loss-of-function effects on the activity | Causal testing of GDE1 function |
| Point mutation knock-in | Catalytic residue requirement | Separation of activity from other functions |
| Overexpression | Gain-of-function effects on metabolite flux | Testing sufficiency of the enzyme |
| Lipidomics | Glycerophosphoinositol and phosphoinositide levels | Pathway flux analysis |
| Metabolite profiling | Myo-inositol and sn-glycerol 3-phosphate levels | Inositol recycling studies |
| Calcium imaging | Downstream calcium signals | Linking activity to signaling |
| Receptor stimulation assays | G protein-coupled receptor regulation | Regulatory mechanism studies |
Enzymatic activity assays
Glycerophosphoinositol glycerophosphodiesterase activity can be measured by incubating cell lysates or recombinant enzyme with glycerophosphoinositol and detecting the products sn-glycerol 3-phosphate and myo-inositol. Such assays were used to show that GDE1/MIR16 has this activity and that it is regulated by G protein-coupled receptor stimulation. Controls should include substrate-only and enzyme-dead mutant conditions to confirm specificity.
CRISPR-based genetic perturbation
CRISPR knockout, point mutation, knock-in and overexpression models allow causal testing of GO:0047395 in cells. Knockout of GDE1 can reveal whether the activity is required for glycerophosphoinositol clearance, while point mutations can separate catalytic activity from scaffolding functions. These approaches are especially useful when combined with receptor stimulation to probe regulation.
Lipid and metabolite profiling
Mass spectrometry-based lipidomics and polar metabolite profiling can quantify glycerophosphoinositol, myo-inositol and sn-glycerol 3-phosphate. Changes in these metabolites after genetic perturbation provide functional evidence for the activity in living cells. Profiling can also connect GO:0047395 to phosphoinositide turnover and calcium signaling [2,4].
Signaling and imaging readouts
Calcium imaging and phosphoinositidase C signaling assays provide downstream readouts of the pathway that produces glycerophosphoinositol [2,7]. Nuclear phosphoinositide signaling can be monitored during growth factor stimulation to assess compartment-specific effects. Combining imaging with genetic models helps link GO:0047395 to cellular physiology [2,8].
How CRISPR Can Be Used to Study GO:0047395 glycerophosphoinositol glycerophosphodiesterase activity
Knockout
CRISPR knockout of GDE1 or related genes can eliminate glycerophosphoinositol glycerophosphodiesterase activity and reveal its contribution to inositol recycling and receptor signaling. Knockout cells are useful for measuring substrate accumulation and downstream calcium or lipid changes. This approach provides direct causal evidence for the role of GO:0047395 in cellular physiology.
Point Mutation
Point mutation knock-in can target catalytic residues to abolish enzyme activity while preserving protein expression and localization. Such models help distinguish the catalytic function of GO:0047395 from non-catalytic roles of the same protein. They are also valuable for testing whether receptor regulation depends on catalytic activity.
Knock-in
Tagged knock-in of GDE1 allows visualization and immunoprecipitation of the endogenous enzyme. This can reveal where glycerophosphoinositol hydrolysis occurs within the cell and how localization changes after receptor stimulation. Knock-in reporters also enable quantitative comparisons between wild-type and mutant alleles.
Overexpression
Overexpression of GDE1 or related enzymes can increase glycerophosphoinositol hydrolysis and alter metabolite pools. This gain-of-function approach tests whether increased activity is sufficient to change phosphoinositide signaling or calcium responses. Overexpression models are also useful for biochemical purification and assay development.
How EDITGENE Supports glycerophosphoinositol glycerophosphodiesterase activity Research
Researchers studying glycerophosphoinositol glycerophosphodiesterase activity-related genes often need to determine whether a candidate gene is causally involved in the reaction, how its catalytic residues work, and whether its activity can be modulated in disease-relevant cell models. EDITGENE provides CRISPR-based tools and bioinformatics support to answer these questions with publication-ready precision.
Contact EDITGENE today to design your custom CRISPR model for glycerophosphoinositol glycerophosphodiesterase activity research.
Frequently Asked Questions About glycerophosphoinositol glycerophosphodiesterase activity
What is glycerophosphoinositol glycerophosphodiesterase activity?
It is the enzymatic activity defined by GO:0047395 that hydrolyzes glycerophosphoinositol to sn-glycerol 3-phosphate, myo-inositol and a proton.
What is the GO ID for glycerophosphoinositol glycerophosphodiesterase activity?
The GO ID is GO:0047395, classified under molecular_function.
What reaction does GO:0047395 catalyze?
It catalyzes 1-(sn-glycero-3-phospho)-1D-myo-inositol + H2O = sn-glycerol 3-phosphate + myo-inositol + H+.
What genes are involved in glycerophosphoinositol glycerophosphodiesterase activity?
GDE1/MIR16 is a well-characterized gene encoding this activity, with upstream regulation by phosphoinositidase C genes such as PLCB1 and PLCG1 [3,4,8].
How is glycerophosphoinositol glycerophosphodiesterase activity regulated?
It is regulated by stimulation of G protein-coupled receptors, linking the activity to receptor-phosphoinositidase C signaling.
What is the substrate of GO:0047395?
The substrate is 1-(sn-glycero-3-phospho)-1D-myo-inositol, also called glycerophosphoinositol.
What are the products of glycerophosphoinositol glycerophosphodiesterase activity?
The products are sn-glycerol 3-phosphate, myo-inositol and a proton.
Why is GO:0047395 important for cell signaling?
It recycles inositol and glycerol phosphate from phosphoinositide turnover, supporting phosphoinositidase C signaling and calcium responses [2,4,7].
Which diseases are linked to glycerophosphoinositol glycerophosphodiesterase activity?
Altered phosphoinositide signaling has been discussed in cancer, neurodegeneration and metabolic contexts, although direct disease links for GO:0047395 require further study [1,8].
How can CRISPR help study GO:0047395?
CRISPR knockout, point mutation, knock-in and overexpression models allow causal testing of the enzyme and its regulatory network.
Conclusion
Glycerophosphoinositol glycerophosphodiesterase activity (GO:0047395) is a defined molecular function that hydrolyzes glycerophosphoinositol to sn-glycerol 3-phosphate, myo-inositol and a proton. It is mechanistically embedded in phosphoinositidase C signaling and regulated by G protein-coupled receptors, making it relevant to calcium signaling, growth factor responses and lipid recycling [2,3,4,7,8]. CRISPR-based models provide a direct route to test the causal roles of GDE1/MIR16 and related genes in health and disease. Continued research on this activity may clarify how cells balance phosphoinositide turnover and inositol availability in cancer, neuronal and metabolic contexts [1,8].
References
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- 3. Zheng B et al.. 2003. GDE1/MIR16 is a glycerophosphoinositol phosphodiesterase regulated by stimulation of G protein-coupled receptors.. Proc Natl Acad Sci U S A 100(4):1745-50 PMID: 12576545
- 4. Wojcikiewicz RJ et al.. 1993. Desensitization of cell signalling mediated by phosphoinositidase C.. Trends Pharmacol Sci 14(7):279-85 PMID: 8212322
- 6. Lo WW et al.. 1987. Receptor-phosphoinositidase C coupling. Multiple G-proteins?. FEBS Lett 224(1):1-3 PMID: 2824238
- 7. Martin TF. 1991. Receptor regulation of phosphoinositidase C.. Pharmacol Ther 49(3):329-45 PMID: 1647037
- 8. Cocco L et al.. 1993. Nuclear phosphoinositidase C during growth factor stimulation.. Adv Enzyme Regul 33:157-69 PMID: 8395135
