GO:0070317 negative regulation of G0 to G1 transition: Quiescence Maintenance, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0070317 describes the biological process that stops, prevents, or reduces the rate of exit from the G0 quiescent state into G1 phase of the cell cycle.
• Maintaining G0 arrest is critical for tissue homeostasis, and its dysregulation contributes to cancer, fibrosis, and impaired immune responses [1, 5].
• Key regulators include cell cycle inhibitors, transcriptional repressors, and signaling pathways that enforce quiescence, such as p53, p21, and RB [1, 7].
• Experimental models for studying this process include knockout, point-mutation, knock-in, and overexpression cell lines, as well as CRISPR library screens [1, 5, 7].
• Dysregulation of G0 to G1 transition control is linked to diseases such as hepatocellular carcinoma, breast cancer, and HIV-1 latency [1, 2, 5].
• Emerging research uses transcriptomics, proteomics, and imaging to dissect the molecular players that maintain quiescence [3, 4, 8].
Description
The transition from the G0 quiescent state to the G1 phase of the cell cycle is a tightly regulated decision point that determines whether a cell will re-enter the proliferative cycle or remain quiescent. The Gene Ontology term GO:0070317, negative regulation of G0 to G1 transition, captures the biological processes that actively prevent or slow this transition, thereby maintaining cell cycle quiescence. This regulation is essential for normal tissue homeostasis, preventing inappropriate proliferation, and preserving stem cell pools [1, 5]. In multicellular organisms, the ability to reversibly exit and re-enter the cell cycle is fundamental for development, tissue repair, and immune function [5, 6]. Dysregulation of this process can lead to uncontrolled proliferation, as seen in cancer, or to pathological quiescence, as observed in some chronic infections and fibrotic diseases [1, 2, 5]. Therefore, understanding the molecular mechanisms that enforce G0 arrest is of broad biomedical importance. Researchers study this process using a variety of model systems, including primary cells, cancer cell lines, and genetically engineered models [3, 4, 7]. The availability of CRISPR-based tools has greatly accelerated the functional dissection of genes involved in maintaining quiescence.
negative regulation of G0 to G1 transition At A Glance
| GO ID | GO:0070317 |
|---|---|
| GO term | negative regulation of G0 to G1 transition |
| Ontology | biological_process |
| Synonym | maintenance of cell cycle quiescence; maintenance of cell quiescence; maintenance of G0 arrest; maintenance of G0 phase |
| Major function | Prevents or slows the re-entry of quiescent cells into the G1 phase of the cell cycle. |
| Related processes | Cell cycle arrest, quiescence, senescence, differentiation [1, 5]. |
| Key regulators | p53, p21, RB, and other cell cycle inhibitors [1, 7]. |
| Disease relevance | Cancer, fibrosis, immune evasion, HIV-1 latency [1, 2, 5]. |
| Research methods | CRISPR knockout, point mutation, knock-in, overexpression, RNA-seq, proteomics [3, 4, 8]. |
What Is GO:0070317?
GO:0070317 negative regulation of G0 to G1 transition is defined as any cell cycle process that stops, prevents, or reduces the rate or extent of the transition from the G0 quiescent state to the G1 phase. In other words, it encompasses the molecular mechanisms that keep a cell in a non-dividing, quiescent state and prevent it from re-entering the active cell cycle. This term is a biological process and includes synonyms such as maintenance of cell cycle quiescence, maintenance of cell quiescence, maintenance of G0 arrest, and maintenance of G0 phase.
Why Is negative regulation of G0 to G1 transition Important in Cell Biology?
Understanding negative regulation of G0 to G1 transition is crucial because it governs fundamental decisions about cell proliferation versus quiescence, impacting tissue homeostasis, regeneration, and disease. In cancer, loss of quiescence maintenance can lead to uncontrolled proliferation, while in chronic infections, maintaining quiescence can allow pathogens like HIV-1 to persist [1, 5]. Moreover, the ability to manipulate this process has therapeutic potential for promoting tissue repair or targeting dormant cancer cells [1, 5].
• Maintains tissue homeostasis by preventing inappropriate cell cycle re-entry.
• Preserves stem cell pools and regenerative capacity [1, 5].
• Dysregulation leads to cancer, as quiescent cells may re-enter the cycle uncontrollably [1, 2].
• Plays a role in immune evasion and HIV-1 latency in macrophages.
• Influences responses to chemotherapy and radiotherapy.
• Key for understanding fibrosis and organ remodeling.
• Provides targets for anti-cancer therapies aimed at dormant cells [1, 8].
• Relevant to aging and age-related diseases.
• Important for developmental processes and tissue patterning.
• Offers insights into plant cell cycle regulation and dormancy.
What Happens During negative regulation of G0 to G1 transition?
Initiation of Quiescence
In simple terms: Cells decide to stop dividing and enter a resting state.
Quiescence is initiated when cells receive anti-proliferative signals or experience stress, leading to the activation of cell cycle inhibitors such as p53 and p21. These inhibitors block the activity of cyclin-dependent kinases (CDKs), preventing phosphorylation of the retinoblastoma protein (RB) and thereby maintaining RB in its active, growth-suppressive state. This results in the sequestration of E2F transcription factors and repression of genes required for G1 progression.
Maintenance of G0 Arrest
In simple terms: The cell actively keeps itself from restarting the division cycle.
Once in G0, cells actively maintain the quiescent state through continued expression of cell cycle inhibitors and transcriptional repressors. For example, the PAI-1 gene is transcriptionally regulated during the G0 to G1 transition in human epidermal keratinocytes, and its expression helps maintain quiescence. Additionally, E2F complexes are modulated during the G0 to S phase transition in human primary B-lymphocytes, and their repression is critical for maintaining G0.
Integration of External Signals
In simple terms: Cells listen to outside signals to decide whether to stay quiet or start dividing.
The decision to remain in G0 or re-enter the cell cycle is influenced by extracellular signals, including growth factors, cytokines, and cell-cell contact. Signaling pathways such as the PI3K/AKT/mTOR pathway and the MAPK cascade integrate these cues and can override quiescence maintenance. In macrophages, cell cycle regulation is critical for susceptibility to HIV-1, and maintaining G0 arrest can restrict viral replication.
Reversible vs. Irreversible Arrest
In simple terms: Some cells can wake up from quiescence, while others are permanently stopped.
Negative regulation of G0 to G1 transition can be reversible, as in quiescent stem cells that can be activated upon injury, or irreversible, as in senescence. The distinction depends on the persistence of inhibitory signals and the epigenetic state of the cell. In cancer, cells may escape quiescence and re-enter the cycle, contributing to tumor growth [1, 2].
Role in Disease and Therapy
In simple terms: When this process goes wrong, it can cause cancer or make infections persist.
Dysregulation of G0 to G1 transition control is implicated in various diseases, including cancer, where loss of quiescence maintenance leads to uncontrolled proliferation [1, 2]. In HIV-1 infection, maintaining macrophages in G0 can limit viral replication, but the virus can also manipulate the cell cycle for its benefit. Targeting the mechanisms that maintain quiescence is a potential therapeutic strategy for cancer and other diseases [1, 8].
Key Genes Involved in GO:0070317 negative regulation of G0 to G1 transition
The following genes and proteins are key players in the negative regulation of G0 to G1 transition, based on published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| TP53 | Induces cell cycle arrest and quiescence in response to stress | Frequently mutated in cancers, leading to loss of quiescence |
| CDKN1A (p21) | Inhibits CDKs, preventing RB phosphorylation and G1 entry | Key mediator of p53-dependent quiescence |
| RB1 | Sequesters E2F transcription factors, repressing G1/S genes | Inactivated in many cancers, causing uncontrolled proliferation |
| E2F1 | Transcription factor that promotes G1/S transition; repressed in quiescence | Target for understanding G0 maintenance |
| SERPINE1 (PAI-1) | Regulated during G0 to G1 transition; may maintain quiescence | Studied in keratinocytes and cancer |
| FBXO5 | Involved in cell cycle regulation; role in gastric cancer | Potential target for cancer therapy |
| CDKN2A (p16) | Inhibits CDK4/6, maintaining RB activity and quiescence | Tumor suppressor often silenced in cancer |
| CCND1 | Cyclin D1 partners with CDK4/6 to phosphorylate RB, promoting G1 entry | Overexpressed in many cancers |
| CDK4 | Phosphorylates RB, driving G1 progression | Target of CDK4/6 inhibitors in cancer therapy |
| CDK6 | Phosphorylates RB, driving G1 progression | Target of CDK4/6 inhibitors |
| MYC | Promotes cell cycle entry and inhibits quiescence | Oncogene frequently overexpressed in cancer |
| FOXO3 | Transcription factor that promotes quiescence and stress resistance | Linked to longevity and cancer suppression |
| KLF4 | Induces quiescence and differentiation | Stem cell factor and tumor suppressor |
| NRF2 | Regulates antioxidant response and can influence quiescence | Implicated in cancer chemoresistance |
| TGFB1 | Cytokine that induces cell cycle arrest and quiescence | Dysregulated in fibrosis and cancer |
| HIF1A | Mediates hypoxia-induced quiescence | Target in cancer and ischemia |
| PTEN | Lipid phosphatase that antagonizes PI3K/AKT, promoting quiescence | Tumor suppressor often lost in cancer |
| CDKN1B (p27) | Inhibits CDKs, contributing to quiescence | Prognostic marker in cancer |
How Is negative regulation of G0 to G1 transition Regulated?
The negative regulation of G0 to G1 transition is controlled by a complex network of signaling pathways and transcriptional programs. Key pathways include the p53-p21 axis, which responds to DNA damage and stress to enforce quiescence. The RB-E2F pathway is central, with RB activity maintained by CDK inhibitors. Extracellular signals such as TGF-beta and contact inhibition activate these pathways. Additionally, metabolic cues via mTOR and AMPK influence the decision to remain quiescent. In macrophages, cell cycle regulation is linked to HIV-1 susceptibility, highlighting the interplay between immune signaling and quiescence. The plant cell cycle also employs similar regulatory logic, with hormones and environmental factors controlling G0 to G1 transition.
negative regulation of G0 to G1 transition and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| TP53 | Cancer (many types) | Knockout cell lines (e.g., HCT116 p53-/-) |
| RB1 | Retinoblastoma, osteosarcoma | Knockout or point-mutation models |
| CDKN2A | Melanoma, pancreatic cancer | Overexpression and knockout cell lines |
| SERPINE1 | Cancer, fibrosis | Knockdown/knockout in keratinocytes |
| FBXO5 | Gastric cancer | Knockout in gastric cancer cell lines |
Cancer
Loss of negative regulation of G0 to G1 transition is a hallmark of cancer, leading to uncontrolled proliferation. Mutations in TP53, RB1, and CDKN2A are common in many cancers, resulting in failure to maintain quiescence. In hepatocellular carcinoma, dysregulation of hepatic growth control contributes to tumorigenesis. In breast cancer, reversal of epithelial-to-mesenchymal transition through epigenetic modulations can affect cell cycle quiescence. Targeting quiescent cancer cells is a therapeutic challenge, as they are often resistant to conventional therapies [1, 8].
HIV-1 Infection
Cell cycle regulation in macrophages is critical for HIV-1 susceptibility. Maintaining macrophages in G0 can restrict HIV-1 replication, while activation to G1 enhances viral production. Thus, negative regulation of G0 to G1 transition plays a role in viral latency and persistence.
Fibrosis
In fibrotic diseases, aberrant activation of quiescent fibroblasts leads to excessive extracellular matrix deposition. Negative regulation of G0 to G1 transition is important for maintaining fibroblast quiescence, and its dysregulation contributes to fibrosis.
Colorectal Cancer
Cell cycle regulation of the G0/G1 transition is altered in 5-fluorouracil-resistant colon cancer cell lines, suggesting that quiescence maintenance affects chemosensitivity. Understanding these mechanisms can inform strategies to overcome drug resistance.
From negative regulation of G0 to G1 transition-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does gene X maintain quiescence? | CRISPR knockout cell line followed by proliferation assays |
| Does mutation Y affect G0 arrest? | Point-mutation knock-in cell line |
| Does overexpression of gene Z induce quiescence? | Overexpression cell line |
| What is the role of gene W in cancer quiescence? | CRISPR library screening in cancer cells |
| How does gene V regulate G0 to G1 transition? | Tagged knock-in for live-cell imaging |
| Does gene U interact with RB/E2F? | Co-immunoprecipitation and knockout models |
How to Study the negative regulation of G0 to G1 transition Process
| Method | What It Measures | Typical Application |
|---|---|---|
| RNA-seq | Gene expression changes | Identify quiescence-associated genes |
| Proteomics | Protein abundance and modifications | Discover signaling pathways |
| Flow cytometry | DNA content and cell cycle phase | Quantify G0/G1 populations |
| Live-cell imaging | Real-time cell cycle dynamics | Track G0 to G1 transition |
| CRISPR knockout screen | Gene function on quiescence | Identify essential genes |
| CRISPR activation screen | Gene overexpression effects | Find drivers of quiescence |
| ChIP-seq | Transcription factor binding | Map E2F and RB occupancy |
| Co-IP | Protein-protein interactions | Study RB-E2F complexes |
Transcriptomics (RNA-seq)
RNA sequencing can identify genes differentially expressed during G0 to G1 transition, revealing regulators of quiescence [3, 4]. For example, PAI-1 transcriptional regulation was studied during this transition in keratinocytes.
Proteomics and Phosphoproteomics
Mass spectrometry-based proteomics can quantify changes in protein abundance and phosphorylation during quiescence maintenance, identifying key signaling nodes.
Imaging and Flow Cytometry
Live-cell imaging with fluorescent reporters for cell cycle phase (e.g., FUCCI) and flow cytometry using DNA dyes or Ki-67 staining allow monitoring of G0/G1 status.
CRISPR Screening
Genome-wide CRISPR knockout or activation screens can identify genes whose loss or gain affects quiescence maintenance, as demonstrated in cancer research.
How CRISPR Can Be Used to Study GO:0070317 negative regulation of G0 to G1 transition
Knockout
CRISPR knockout of candidate genes can determine whether they are required for maintaining G0 arrest. For example, knocking out TP53 or RB1 leads to loss of quiescence and increased proliferation. Knockout models are also used to study genes like FBXO5 in gastric cancer.
Point Mutation
Introducing specific point mutations (e.g., in CDK4 or CDK6) can mimic cancer-associated variants and reveal their impact on G0 to G1 transition. Point-mutation knock-in models help dissect the function of individual residues in quiescence regulation.
Knock-in
Knock-in of tagged versions of proteins (e.g., GFP-RB1) allows live-cell imaging of protein dynamics during quiescence maintenance. Knock-in of reporter genes under the control of quiescence-specific promoters can enable sorting of G0 cells.
Overexpression
Overexpression of cell cycle inhibitors such as p21 or p27 can induce quiescence in cancer cells, providing a model to study the mechanisms of G0 arrest. Overexpression of oncogenes like MYC can overcome quiescence and drive proliferation.
How EDITGENE Supports negative regulation of G0 to G1 transition Research
Researchers studying negative regulation of G0 to G1 transition-related genes often need to determine whether a candidate gene is causally involved in maintaining quiescence or driving re-entry into the cell cycle. EDITGENE provides a comprehensive suite of CRISPR-based services to facilitate these investigations, from gene knockout to precise point mutations and overexpression models.
Contact EDITGENE today to design your custom CRISPR model for negative regulation of G0 to G1 transition research.
Frequently Asked Questions About negative regulation of G0 to G1 transition
What is negative regulation of G0 to G1 transition?
It is the biological process that stops or slows the transition from the G0 quiescent state to the G1 phase of the cell cycle, helping maintain cell cycle arrest.
What genes are involved in negative regulation of G0 to G1 transition?
Key genes include TP53, CDKN1A (p21), RB1, CDKN2A (p16), and FBXO5, among others [1, 8].
Why is maintenance of G0 arrest important?
It prevents inappropriate cell proliferation, preserves stem cell pools, and its dysregulation contributes to cancer and other diseases [1, 5].
How is negative regulation of G0 to G1 transition studied?
Researchers use CRISPR knockout, point mutation, knock-in, overexpression models, RNA-seq, proteomics, and imaging [3, 4, 8].
What diseases are linked to defects in G0 to G1 transition control?
Cancer, fibrosis, HIV-1 latency, and chemoresistance are associated with dysregulation of this process [1, 2, 5, 7].
What is the role of p53 in G0 arrest?
p53 induces p21, which inhibits CDKs, preventing RB phosphorylation and maintaining quiescence.
How does HIV-1 interact with macrophage cell cycle?
HIV-1 replication is enhanced when macrophages transition from G0 to G1, so maintaining G0 restricts the virus.
Can CRISPR be used to study G0 to G1 transition?
Yes, CRISPR knockout and activation screens are powerful tools to identify genes that regulate quiescence.
What are the synonyms for negative regulation of G0 to G1 transition?
Synonyms include maintenance of cell cycle quiescence, maintenance of cell quiescence, maintenance of G0 arrest, and maintenance of G0 phase.
What is the GO ID for negative regulation of G0 to G1 transition?
The GO ID is GO:0070317.
Conclusion
Negative regulation of G0 to G1 transition (GO:0070317) is a fundamental biological process that maintains cell cycle quiescence and prevents inappropriate proliferation. Its dysregulation is implicated in cancer, fibrosis, and infectious diseases, making it a critical area of research. Advances in CRISPR-based models and high-throughput technologies continue to uncover the complex regulatory networks that enforce G0 arrest, offering new opportunities for therapeutic intervention.
References
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- 2. Nimal S et al.. 2025. Reversal of epithelial to mesenchymal transition in triple negative breast cancer through epigenetic modulations by dietary flavonoid Galangin and its combination with SAHA.. Cell Commun Signal 23(1):163 PMID: 40176095
- 3. Qi L et al.. 2006. PAI-1 transcriptional regulation during the G0 --> G1 transition in human epidermal keratinocytes.. J Cell Biochem 99(2):495-507 PMID: 16622840
- 4. van der Sman J et al.. 1999. Modulation of E2F complexes during G0 to S phase transition in human primary B-lymphocytes.. J Biol Chem 274(17):12009-16 PMID: 10207023
- 5. Ferreira IATM et al.. 2020. Cell Cycle Regulation in Macrophages and Susceptibility to HIV-1.. Viruses 12(8) PMID: 32751972
- 6. Francis D. 2007. The plant cell cycle--15 years on.. New Phytol 174(2):261-278 PMID: 17388890
- 7. McGinn CJ et al.. 2000. Cell cycle regulation of the G0/G1 transition in 5-fluorouracil-sensitive and -resistant human colon cancer cell lines.. Cancer J 6(4):234-42 PMID: 11038143
- 8. Zhang J et al.. 2023. Exploring the role of FBXO5 in gastric cancer.. Mol Cell Probes 69:101915 PMID: 37121410
