GO:0051896 regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction: Signaling Pathway, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0051896 describes any process that modulates the frequency, rate or extent of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signal transduction, a central pathway controlling cell growth, survival, metabolism and motility.
• The pathway is initiated by PI3K-mediated generation of PI(3,4,5)P3 at membranes, which recruits AKT and its activators PDK1 and mTORC2, leading to AKT phosphorylation and downstream signaling.
• Dysregulation of PI3K/AKT signaling is implicated in cancer, metabolic disorders, cardiovascular disease and premature ovarian failure, making it a major therapeutic target.
• Natural products and synthetic inhibitors targeting PI3K, AKT and mTOR are actively investigated as anticancer strategies.
• Key genes include PIK3CA, PIK3CB, AKT1, AKT2, AKT3, PTEN, PDPK1, MTOR, RICTOR, TSC1/2 and FOXO3A, among others.
• CRISPR-based knockout, point mutation, knock-in and overexpression models enable causal dissection of this pathway in disease and development.
Description
The phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling axis is one of the most frequently deregulated pathways in human disease, governing fundamental processes such as cell proliferation, survival, metabolism and migration. The Gene Ontology term GO:0051896, regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction, captures the diverse molecular events that modulate the amplitude, duration and spatial organization of this cascade. Understanding how this regulation is achieved is essential for interpreting disease mechanisms and for developing targeted therapies. At the molecular level, PI3K phosphorylates phosphatidylinositol (4,5)-bisphosphate (PIP2) to generate phosphatidylinositol (3,4,5)-trisphosphate (PIP3), which serves as a docking site for AKT and its upstream kinases PDK1 and mTORC2. This membrane recruitment is tightly controlled by phosphatases such as PTEN and by feedback loops involving mTOR and FOXO transcription factors. The spatial organization of these events, including focal adhesion-associated signaling, further refines pathway output. Because of its broad impact, researchers across cancer biology, immunology, neuroscience and metabolism study GO:0051896 using genetic, pharmacological and imaging approaches. This article provides a structured overview of the term, its core mechanisms, key genes, disease links and experimental strategies, with an emphasis on CRISPR-based models for functional validation.
regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction At A Glance
| GO ID | GO:0051896 |
|---|---|
| GO term | regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction |
| Ontology | biological_process |
| Synonym | regulation of PI3K/Akt signal transduction; regulation of AKT signaling cascade; regulation of protein kinase B signaling; regulation of PI3K-PKB/Akt pathway |
| Major function | Modulates the frequency, rate or extent of PI3K/AKT signal transduction, thereby controlling cell growth, survival, metabolism and motility. |
| Upstream regulators | Receptor tyrosine kinases, G-protein coupled receptors, integrins, PTEN, and phosphatases such as PPM1G. |
| Core effectors | PI3K (PIK3CA/B), AKT1/2/3, PDK1, mTORC2, FOXO transcription factors. |
| Disease relevance | Cancer, metabolic disorders, cardiovascular disease, premature ovarian failure, chronic atrophic gastritis. |
| Research methods | CRISPR knockout/knock-in, RNA-seq, phosphoproteomics, live-cell imaging, pharmacological inhibitors. |
What Is GO:0051896?
GO:0051896 is a biological process term defined as any process that modulates the frequency, rate or extent of phosphatidylinositol 3-kinase/protein kinase B signal transduction. In other words, it encompasses all regulatory inputs that tune the PI3K-AKT signaling cascade, including activation, inhibition, feedback control and spatial restriction, without being the signaling event itself.
Why Is regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction Important in Cell Biology?
GO:0051896 is critically important because the PI3K/AKT pathway is a master regulator of cell fate and is frequently hijacked in human diseases. Aberrant activation drives tumorigenesis, while excessive or insufficient signaling contributes to metabolic, inflammatory and degenerative conditions. Understanding its regulation provides a framework for therapeutic intervention and for interpreting genomic data in precision medicine.
• Controls cell proliferation and survival, making it a hallmark of cancer.
• Regulates glucose metabolism and insulin sensitivity, linking to diabetes and obesity.
• Modulates immune cell function and inflammation.
• Influences ovarian function and fertility, as shown in premature ovarian failure models.
• Plays a role in gastric mucosal homeostasis and chronic atrophic gastritis.
• Is targeted by numerous natural products and synthetic inhibitors for cancer therapy.
• Spatial organization at focal adhesions fine-tunes AKT signaling output.
• Feedback loops involving mTOR and FOXO3A determine pathway dynamics.
• Genetic alterations in PIK3CA, PTEN and AKT are common in human tumors.
• CRISPR screens can identify novel regulators of this pathway.
What Happens During regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction?
Initiation and PIP3 generation
In simple terms: The pathway starts when PI3K enzymes are activated and produce a lipid signal called PIP3 at the cell membrane.
Regulation begins with the activation of class I PI3K isoforms (e.g., PIK3CA, PIK3CB) downstream of receptor tyrosine kinases, G-protein coupled receptors or integrins. Activated PI3K phosphorylates PIP2 to generate PIP3, a lipid second messenger that recruits pleckstrin homology (PH) domain-containing proteins to the membrane. This step is tightly controlled by the opposing phosphatase PTEN, which dephosphorylates PIP3 back to PIP2, thereby terminating the signal.
AKT recruitment and phosphorylation
In simple terms: PIP3 acts like a docking station that brings AKT to the membrane, where it gets switched on by other kinases.
PIP3 binds to the PH domain of AKT, recruiting it to the plasma membrane. There, PDK1 phosphorylates AKT at Thr308, and mTORC2 phosphorylates it at Ser473, leading to full AKT activation. This dual phosphorylation is a key regulatory node and is often used as a readout of pathway activity.
Spatial organization and focal adhesions
In simple terms: The pathway does not happen everywhere in the cell at once; it is organized into specific locations like focal adhesions.
Recent evidence shows that PI3K-PI(3,4,5)P3-AKT signaling is spatially organized by focal adhesions, which serve as signaling hubs that concentrate components and modulate pathway output. This spatial regulation ensures that AKT signals to the correct downstream targets at the right time and place.
Downstream effectors and feedback
In simple terms: Once active, AKT turns on many proteins that control cell growth and survival, and the pathway can shut itself down through feedback loops.
Activated AKT phosphorylates numerous substrates, including FOXO transcription factors, TSC2, GSK3 and mTOR, thereby influencing cell cycle progression, apoptosis, metabolism and protein synthesis. Negative feedback loops, such as mTORC1-mediated inhibition of IRS-1, and phosphatases like PPM1G, fine-tune the duration and intensity of signaling.
Regulation by phosphatases and translational control
In simple terms: Enzymes called phosphatases can remove phosphate groups from signaling proteins, acting as brakes on the pathway.
The PPM1G phosphatase regulates PI3K-dependent translational control of Id1, illustrating how phosphatases can modulate downstream outputs of the pathway. Additionally, PTEN and SHIP phosphatases directly oppose PI3K activity, and their loss leads to constitutive AKT activation.
Key Genes Involved in GO:0051896 regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction
The following genes and proteins are central to the regulation of PI3K/AKT signal transduction (GO:0051896) and are frequently studied in disease and drug discovery.
| Gene | Major Role | Research Relevance |
|---|---|---|
| PIK3CA | Encodes p110α catalytic subunit of PI3K; generates PIP3 | Frequently mutated in cancer; target of inhibitors |
| PIK3CB | Encodes p110β catalytic subunit; mediates integrin signaling | Role in platelet function and cancer |
| PIK3R1 | Regulatory subunit p85α; stabilizes and inhibits p110 | Mutations affect PI3K activity in cancer and immune disorders |
| AKT1 | Serine/threonine kinase; phosphorylates downstream targets | Oncogene; regulates survival and metabolism |
| AKT2 | AKT isoform; involved in insulin signaling | Linked to diabetes and cancer |
| AKT3 | AKT isoform; enriched in brain | Implicated in melanoma and neurodevelopment |
| PTEN | Lipid phosphatase; dephosphorylates PIP3 | Tumor suppressor; loss activates AKT |
| PDPK1 | PDK1 kinase; phosphorylates AKT at Thr308 | Essential for AKT activation |
| MTOR | Kinase in mTORC1 and mTORC2; phosphorylates AKT Ser473 | Central regulator of growth and feedback |
| RICTOR | Component of mTORC2; required for AKT Ser473 phosphorylation | Target for pathway modulation |
| TSC1 | Tumor suppressor; inhibits mTORC1 | Mutations cause tuberous sclerosis |
| TSC2 | Tumor suppressor; inhibited by AKT | Links PI3K to mTORC1 |
| FOXO3A | Transcription factor inhibited by AKT | Regulates apoptosis and oxidative stress |
| GSK3B | Kinase inhibited by AKT | Controls metabolism and gene expression |
| PPM1G | Phosphatase; regulates translational control of Id1 | Modulates PI3K-dependent translation |
| ID1 | Transcription regulator; downstream of PI3K | Involved in cell growth and differentiation |
| RPTOR | Component of mTORC1; integrates nutrient signals | Feedback regulation of PI3K/AKT |
| IRS1 | Insulin receptor substrate; upstream of PI3K | Feedback inhibition by mTORC1 |
How Is regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction Regulated?
Regulation of PI3K/AKT signaling is achieved through multiple layers: receptor tyrosine kinase activation, phosphatase activity (PTEN, PPM1G), lipid second messengers (PIP3), and feedback loops involving mTORC1 and FOXO transcription factors. Spatial confinement at focal adhesions further modulates pathway output. Additionally, natural products and pharmacological agents can either activate or inhibit the pathway, as shown in cancer and ovarian failure models.
regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| PIK3CA | Cancer (breast, colorectal, endometrial) | Knock-in of activating mutations in cell lines; xenograft models |
| PTEN | Cancer, Cowden syndrome | Knockout in cancer cell lines; mouse models |
| AKT1 | Cancer, metabolic syndrome | Point mutation (E17K) knock-in; overexpression |
| FOXO3A | Premature ovarian failure, oxidative stress | Knockout or knockdown in ovarian cells; rat models |
| TSC1/TSC2 | Tuberous sclerosis complex | Knockout in neuronal or renal cells |
Cancer
Constitutive activation of PI3K/AKT signaling is a hallmark of many cancers, driven by mutations in PIK3CA, loss of PTEN, or amplification of AKT. Targeting this pathway with natural products or synthetic inhibitors is a major therapeutic strategy. For example, quercetin modulates the PI3K/Akt/FoxO3a pathway in ovarian failure models, and chitosan derivatives affect the pathway in cancer therapy.
Metabolic and gastrointestinal disorders
The pathway regulates glucose homeostasis and liver function. Roux-en-Y gastric bypass improves liver and glucose homeostasis in diabetic rats by upregulating trefoil factor family 3 and activating PI3K/AKT signaling. In chronic atrophic gastritis, a traditional Chinese medicine decoction modulates PI3K/AKT/mTORC2 signaling and gastrin content.
Reproductive and oxidative stress
PI3K/AKT signaling is involved in ovarian function. In a rat model of cyclophosphamide-induced premature ovarian failure, quercetin treatment regulated the PI3K/Akt/FoxO3a pathway and reduced oxidative stress.
Platelet and cardiovascular biology
PI3Kβ plays a specific role in platelet integrin α2β1 signaling, linking the pathway to thrombosis and hemostasis. This highlights the importance of isoform-specific regulation in cardiovascular contexts.
From regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of PTEN activate AKT signaling? | PTEN knockout cell lines (e.g., CRISPR KO) |
| What is the effect of PIK3CA hotspot mutation? | Point mutation knock-in (e.g., H1047R) |
| How does AKT1 E17K mutation affect downstream targets? | Knock-in of AKT1 E17K in isogenic cells |
| Where is AKT localized upon activation? | Tagged knock-in of AKT1 with fluorescent protein |
| Does overexpression of RICTOR enhance AKT Ser473 phosphorylation? | Overexpression of RICTOR in cell lines |
| Can FOXO3A rescue oxidative stress in ovarian failure? | FOXO3A overexpression or knockout in ovarian cells |
How to Study the regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Western blot | Phosphorylation status of AKT and substrates | Pathway activation in cells and tissues |
| Phosphoproteomics | Global phosphorylation changes | Identifying novel regulators and feedback |
| Live-cell imaging | Spatiotemporal dynamics of AKT and PIP3 | Spatial organization at focal adhesions |
| CRISPR knockout screen | Loss-of-function effects on pathway | Discovering essential regulators |
| RNA-seq | Transcriptional changes downstream of AKT | FOXO target gene expression |
| Co-immunoprecipitation | Protein-protein interactions | Complex formation of PI3K, AKT, mTORC2 |
| Lipid kinase assay | PI3K enzymatic activity | Direct measurement of PIP3 production |
Phosphoproteomics and Western blotting
Measuring phosphorylation of AKT at Thr308 and Ser473, and of downstream substrates, is standard for assessing pathway activity. Phosphoproteomics can identify novel regulatory nodes and feedback loops.
Live-cell imaging and spatial analysis
Fluorescently tagged AKT and PIP3 biosensors allow real-time visualization of pathway dynamics at focal adhesions and other subcellular locations. This reveals spatial regulation that bulk assays miss.
CRISPR screens and functional genomics
Genome-wide CRISPR knockout or activation screens can identify genes that regulate PI3K/AKT signaling, such as phosphatases, kinases and adaptor proteins. These screens are powerful for discovering new therapeutic targets.
Pharmacological inhibition and natural product testing
Small molecule inhibitors (e.g., LY294002, MK-2206) and natural products (e.g., quercetin, chitosan) are used to modulate the pathway and assess phenotypic outcomes in cancer and other diseases.
How CRISPR Can Be Used to Study GO:0051896 regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction
Knockout
CRISPR knockout of key genes such as PTEN, PIK3CA or AKT1 allows researchers to determine their causal role in PI3K/AKT signaling. For example, PTEN knockout leads to constitutive AKT activation, mimicking cancer-associated loss. Knockout of FOXO3A can reveal its contribution to oxidative stress responses.
Point Mutation
Introducing specific point mutations, such as AKT1 E17K or PIK3CA H1047R, via CRISPR base editing or homology-directed repair, creates isogenic models to study oncogenic activation and drug sensitivity. These models are valuable for testing targeted therapies.
Knock-in
Knock-in of fluorescent tags (e.g., GFP-AKT1) or epitope tags enables live-cell imaging and proteomic analysis of pathway components. Knock-in of mutant alleles can also model disease-associated variants.
Overexpression
CRISPR activation (CRISPRa) or lentiviral overexpression can elevate levels of genes like RICTOR, AKT1 or PIK3CA to study pathway hyperactivation and downstream effects. Overexpression of FOXO3A can rescue phenotypes in ovarian failure models.
How EDITGENE Supports regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction Research
Researchers studying regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction-related genes often need to determine whether a candidate gene is causally involved in pathway regulation or disease. EDITGENE provides a comprehensive suite of CRISPR-based services to generate precisely engineered cell models, enabling functional validation and drug discovery.
Contact EDITGENE today to design your custom CRISPR model for regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction research.
Frequently Asked Questions About regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction
What is GO:0051896?
GO:0051896 is the Gene Ontology term for regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction, describing any process that modulates the frequency, rate or extent of PI3K/AKT signaling.
What genes are involved in regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction?
Key genes include PIK3CA, PIK3CB, AKT1, AKT2, AKT3, PTEN, PDPK1, MTOR, RICTOR, TSC1, TSC2 and FOXO3A.
Why is PI3K/AKT signaling important in cancer?
Constitutive activation of PI3K/AKT signaling promotes cell survival and proliferation, and is frequently caused by PIK3CA mutations or PTEN loss, making it a major therapeutic target.
How is PI3K/AKT signaling regulated?
It is regulated by receptor activation, lipid phosphatases like PTEN, kinases such as PDK1 and mTORC2, and feedback loops involving mTORC1 and FOXO.
What diseases are linked to PI3K/AKT dysregulation?
Cancer, metabolic disorders, premature ovarian failure, chronic atrophic gastritis and platelet disorders are among the diseases linked to this pathway.
What methods are used to study PI3K/AKT signaling?
Common methods include Western blotting for phospho-AKT, phosphoproteomics, live-cell imaging, CRISPR screens and pharmacological inhibition.
How can CRISPR help study PI3K/AKT signaling?
CRISPR knockout, point mutation knock-in, tagged knock-in and overexpression models allow causal interrogation of genes in the pathway.
What is the role of PTEN in PI3K/AKT signaling?
PTEN is a lipid phosphatase that dephosphorylates PIP3, thereby opposing PI3K activity and acting as a tumor suppressor.
Can natural products modulate PI3K/AKT signaling?
Yes, natural products such as quercetin and chitosan derivatives have been shown to modulate the pathway in cancer and ovarian failure models.
How does spatial organization affect PI3K/AKT signaling?
Focal adhesions serve as signaling hubs that spatially organize PI3K, PIP3 and AKT, influencing pathway output and specificity.
Conclusion
GO:0051896, regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction, represents a central regulatory node in cell biology with profound implications for human disease. Its complexity, from lipid second messengers to spatial organization and feedback loops, demands sophisticated experimental models. CRISPR-based approaches, combined with phosphoproteomics and imaging, offer powerful ways to dissect this pathway and identify new therapeutic targets.
References
- 1. Tewari D et al.. 2022. Natural products targeting the PI3K-Akt-mTOR signaling pathway in cancer: A novel therapeutic strategy.. Semin Cancer Biol 80:1-17 PMID: 31866476
- 2. Wang J et al.. 2024. Spatial organization of PI3K-PI(3,4,5)P(3)-AKT signaling by focal adhesions.. Mol Cell 84(22):4401-4418.e9 PMID: 39488211
- 3. Zheng S et al.. 2022. Effects of quercetin on ovarian function and regulation of the ovarian PI3K/Akt/FoxO3a signalling pathway and oxidative stress in a rat model of cyclophosphamide-induced premature ovarian failure.. Basic Clin Pharmacol Toxicol 130(2):240-253 PMID: 34841658
- 4. Xu K et al.. 2016. Phosphatidylinositol-3 kinase-dependent translational regulation of Id1 involves the PPM1G phosphatase.. Oncogene 35(44):5807-5816 PMID: 27065332
- 5. Amirani E et al.. 2020. Effects of chitosan and oligochitosans on the phosphatidylinositol 3-kinase-AKT pathway in cancer therapy.. Int J Biol Macromol 164:456-467 PMID: 32693135
- 6. Consonni A et al.. 2012. Role and regulation of phosphatidylinositol 3-kinase β in platelet integrin α2β1 signaling.. Blood 119(3):847-56 PMID: 22106345
- 7. Xia Z et al.. 2025. Effect of Jiawei Huangqi Guizhi decoction on the expression of gastrin content and phosphatidylinositol 3-kinase/ protein kinase B/mechanistic target of rapamycin complex 2 signalling pathways in rats with chronic atrophic gastritis.. J Tradit Chin Med 45(4):770-776 PMID: 40810222
- 8. Song K et al.. 2025. Roux-en-Y gastric bypass improves liver and glucose homeostasis in Zucker diabetic fatty rats by upregulating hepatic trefoil factor family 3 and activating the phosphatidylinositol 3-kinase/protein kinase B pathway.. Surg Obes Relat Dis 21(7):792-805 PMID: 39893149
