GO:0042636 negative regulation of hair cycle: Mechanism, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0042636 (negative regulation of hair cycle) describes any process that stops, prevents, or reduces the frequency, rate, or extent of the cyclical phases of hair growth (anagen), regression (catagen), quiescence (telogen), and shedding (exogen).
• Dermal macrophages that express TREM2 secrete Oncostatin M to maintain hair follicle stem cell quiescence and inhibit hair growth, providing a direct cellular mechanism for negative regulation of the hair cycle.
• FGF5 is a secreted signaling protein that acts as a dominant inhibitor of hair elongation and is a well-established negative regulator of the hair cycle across mammals.
• The PD-1/PD-L1 pathway participates in murine hair cycle transition and can act as a potential anagen phase regulator, linking immune checkpoint signaling to hair cycle control.
• Non-coding RNAs and epigenetic mechanisms, including miR-877-3p targeting IGFBP5 and DNA methylation-mediated lncRNA2919 regulation, fine-tune hair follicle regeneration and cycle progression.
• CRISPR-based knockout, point mutation, knock-in, and overexpression models enable causal testing of candidate negative regulators of the hair cycle in vitro and in vivo.
Description
The hair cycle is a tightly orchestrated biological process comprising anagen (growth), catagen (regression), telogen (quiescence), and exogen (shedding). Negative regulation of the hair cycle (GO:0042636) refers to any process that stops, prevents, or reduces the frequency, rate, or extent of these cyclical phases. This ontology term is essential for researchers seeking to understand how hair growth is restrained under physiological conditions and how its dysregulation contributes to hair loss disorders, wound healing, and epithelial stem cell biology. Mechanistically, negative regulation of the hair cycle is achieved through diverse signaling and cellular inputs. Dermal macrophages expressing TREM2 secrete Oncostatin M to maintain hair follicle stem cell quiescence and inhibit hair growth, directly linking immune cell populations to hair cycle suppression. The PD-1/PD-L1 pathway has also been implicated in murine hair cycle transition, acting as a potential anagen phase regulator. In addition, secreted factors such as FGF5 function as dominant inhibitors of hair elongation, and their localization in skin macrophage-like cells and hair follicles suggests a conserved role in hair growth cycle regulation. Beyond protein-coding signals, non-coding RNAs and epigenetic modifications contribute to negative regulation of the hair cycle. For example, miR-877-3p targets IGFBP5 to regulate the secondary hair follicle cycle in cashmere goats, while DNA methylation mediates lncRNA2919 regulation of hair follicle regeneration. Understanding these layered control mechanisms is critical for developing targeted interventions in hair follicle biology and regenerative medicine.
negative regulation of hair cycle At A Glance
| GO ID | GO:0042636 |
|---|---|
| GO term | negative regulation of hair cycle |
| Ontology | biological_process |
| Synonym | down regulation of hair cycle; down-regulation of hair cycle; downregulation of hair cycle; inhibition of hair cycle |
| Major function | Stops, prevents, or reduces the frequency, rate, or extent of anagen, catagen, telogen, and exogen phases of the hair cycle |
| Cellular context | Hair follicle stem cells, dermal macrophages, and skin microenvironment |
| Key signaling inputs | Oncostatin M, FGF5, PD-1/PD-L1, IGFBP5, and non-coding RNAs |
| Research relevance | Hair loss disorders, regenerative medicine, epithelial stem cell quiescence, and gene editing model development |
What Is GO:0042636?
GO:0042636 (negative regulation of hair cycle) is a biological process term defined as any process that stops, prevents, or reduces the frequency, rate, or extent of the cyclical phases of growth (anagen), regression (catagen), quiescence (telogen), and shedding (exogen) in the life of a hair. In practical terms, it encompasses molecular, cellular, and systemic mechanisms that suppress or delay hair follicle cycling, thereby maintaining follicles in a quiescent or slowed state.
Why Is negative regulation of hair cycle Important in Cell Biology?
Negative regulation of the hair cycle is important because it governs the balance between hair follicle activation and quiescence, a balance that is disrupted in common hair loss conditions and that influences epithelial stem cell behavior during wound healing and tissue regeneration. Understanding the molecular players that suppress hair cycling, such as Oncostatin M secreted by TREM2+ dermal macrophages, FGF5, and immune checkpoint pathways, provides actionable targets for therapeutic modulation of hair growth. Moreover, because hair follicle stem cells serve as a paradigm for adult stem cell quiescence, studying negative regulation of the hair cycle offers broader insights into stem cell biology and regenerative medicine.
• Provides a mechanistic framework for understanding how hair follicle stem cells are maintained in quiescence.
• Identifies secreted factors such as Oncostatin M and FGF5 as dominant inhibitors of hair growth.
• Links immune checkpoint signaling (PD-1/PD-L1) to hair cycle transition and anagen regulation.
• Highlights non-coding RNA and epigenetic control of hair follicle regeneration, including miR-877-3p/IGFBP5 and lncRNA2919.
• Offers candidate targets for therapeutic intervention in hair loss and excessive hair growth disorders.
• Serves as a model for studying adult stem cell quiescence and tissue regeneration.
• Enables comparative studies across species, including cashmere goats and murine models.
• Supports development of CRISPR-based disease models to test causal roles of candidate genes.
What Happens During negative regulation of hair cycle?
Immune cell-mediated suppression of hair follicle stem cell activation
In simple terms: Certain immune cells in the skin send signals that keep hair follicle stem cells asleep, preventing hair from growing.
A subset of TREM2+ dermal macrophages secretes Oncostatin M to maintain hair follicle stem cell quiescence and inhibit hair growth, providing a direct cellular mechanism for negative regulation of the hair cycle. This macrophage-stem cell axis represents a key checkpoint that stops or reduces the frequency of anagen entry.
Secreted growth factor inhibition by FGF5
In simple terms: FGF5 is a protein that acts as a brake on hair elongation, keeping hair from growing too long.
FGF5 is a secreted signaling protein that functions as a dominant inhibitor of hair elongation and is a well-established negative regulator of the hair cycle across mammals. Localization studies in rat skin have identified FGF-5 protein in macrophage-like cells and FGF-5S protein in hair follicles, suggesting that two Fgf-5 gene products participate in hair growth cycle regulation.
Immune checkpoint signaling through PD-1/PD-L1
In simple terms: The PD-1/PD-L1 pathway, known for controlling immune responses, also helps regulate the switch between hair growth phases.
The PD-1/PD-L1 pathway has been implicated in murine hair cycle transition and is described as a potential anagen phase regulator. This finding links immune checkpoint molecules to the negative regulation of hair cycle progression, expanding the repertoire of signaling systems that can suppress hair growth.
Non-coding RNA and epigenetic fine-tuning
In simple terms: Small RNA molecules and chemical tags on DNA can dial down hair follicle regeneration, adding another layer of control.
miR-877-3p targets IGFBP5 to regulate the secondary hair follicle cycle in cashmere goats, demonstrating microRNA-mediated negative regulation of hair cycling. In addition, DNA methylation mediates lncRNA2919 regulation of hair follicle regeneration, showing that epigenetic modifications contribute to the suppression of hair follicle cycling.
Integration of suppressive signals at the hair follicle
In simple terms: The hair follicle receives many stop signals at once, and these signals are integrated to decide whether hair grows or rests.
Negative regulation of the hair cycle integrates immune, secreted factor, checkpoint, and epigenetic inputs to stop, prevent, or reduce the frequency, rate, or extent of anagen, catagen, telogen, and exogen. This integration ensures that hair follicle stem cells remain quiescent unless activating signals overcome the suppressive threshold.
Key Genes Involved in GO:0042636 negative regulation of hair cycle
The following genes and proteins have been experimentally linked to negative regulation of the hair cycle (GO:0042636) in published studies.
| Gene | Major Role | Research Relevance |
|---|---|---|
| TREM2 | Expressed on a subset of dermal macrophages that secrete Oncostatin M to maintain hair follicle stem cell quiescence | Target for studying immune-stem cell crosstalk in hair cycle suppression |
| OSM | Oncostatin M secreted by TREM2+ macrophages inhibits hair growth and maintains stem cell quiescence | Candidate therapeutic target for modulating hair follicle quiescence |
| FGF5 | Secreted signaling protein that acts as a dominant inhibitor of hair elongation | Well-established negative regulator of hair cycle across mammals |
| FGF5S | Alternative FGF-5 gene product localized in hair follicle, implicated in hair growth cycle regulation | Isoform-specific studies of FGF5 function in hair cycling |
| PD-1 | Immune checkpoint receptor involved in murine hair cycle transition as a potential anagen phase regulator | Links immune checkpoint biology to hair cycle control |
| PD-L1 | Ligand for PD-1 implicated in hair cycle transition | Target for studying checkpoint-mediated hair growth regulation |
| IGFBP5 | Target of miR-877-3p in regulation of secondary hair follicle cycle in cashmere goats | Model for microRNA-mediated hair cycle regulation |
| miR-877-3p | MicroRNA that targets IGFBP5 to regulate secondary hair follicle cycle | Non-coding RNA regulator of hair cycling |
| lncRNA2919 | Long non-coding RNA regulated by DNA methylation that influences hair follicle regeneration | Epigenetic regulator of hair follicle regeneration |
| GLI2 | Transcription factor regulated by Sufu and Spop, implicated in hair cell differentiation control | Provides mechanistic parallels for negative regulation in related systems |
| SUFU | Negative regulator of GLI2 in cochlear hair cell differentiation | Model for negative regulation of hair cell differentiation |
| SPOP | Mediates regulation of GLI2 in cochlear hair cell differentiation | Model for ubiquitin-mediated negative regulation |
| p27Kip1 | Cell cycle inhibitor regulated during gentamicin-mediated hair cell death | Links cell cycle control to hair cell survival |
How Is negative regulation of hair cycle Regulated?
Negative regulation of the hair cycle is controlled by a layered network of secreted factors, immune signals, and epigenetic modifiers. TREM2+ dermal macrophages secrete Oncostatin M to maintain hair follicle stem cell quiescence and inhibit hair growth, establishing a paracrine suppression mechanism. FGF5 acts as a dominant inhibitor of hair elongation, and its two gene products, FGF-5 and FGF-5S, are localized in skin macrophage-like cells and hair follicles, suggesting autocrine and paracrine regulation. The PD-1/PD-L1 pathway participates in murine hair cycle transition and may regulate anagen entry. At the epigenetic level, DNA methylation mediates lncRNA2919 regulation of hair follicle regeneration, and miR-877-3p targets IGFBP5 to modulate the secondary hair follicle cycle. Together, these mechanisms ensure that hair follicle cycling is restrained under appropriate physiological conditions.
negative regulation of hair cycle and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| TREM2 | Hair follicle stem cell quiescence and hair loss | Knockout mouse and macrophage co-culture |
| OSM | Inhibition of hair growth and stem cell quiescence | Overexpression and neutralizing antibody models |
| FGF5 | Hair elongation and hair cycle regulation | Knockout and transgenic animal models |
| PD-1/PD-L1 | Hair cycle transition and anagen regulation | Murine hair cycle transition models |
| IGFBP5 | Secondary hair follicle cycle in cashmere goats | miR-877-3p mimic/inhibitor in goat models |
Hair loss disorders and alopecia
Negative regulation of the hair cycle is directly relevant to hair loss disorders because excessive suppression of anagen entry or premature catagen induction can lead to reduced hair growth. TREM2+ dermal macrophages that secrete Oncostatin M maintain hair follicle stem cell quiescence and inhibit hair growth, and dysregulation of this axis may contribute to alopecia. FGF5, a dominant inhibitor of hair elongation, is a well-established negative regulator whose modulation affects hair length and cycling. Understanding these pathways provides a rationale for targeting negative regulators to promote hair regrowth.
Immune checkpoint therapy and hair cycle effects
The PD-1/PD-L1 pathway is a major immune checkpoint in cancer therapy, and its role in murine hair cycle transition as a potential anagen phase regulator suggests that checkpoint blockade may influence hair cycling. This connection highlights the importance of studying negative regulation of the hair cycle in the context of immunotherapy and its dermatologic side effects.
Regenerative medicine and stem cell quiescence
Hair follicle stem cells are a paradigm for adult stem cell quiescence, and negative regulation of the hair cycle controls their activation. TREM2+ macrophage-derived Oncostatin M maintains quiescence, and epigenetic regulators such as lncRNA2919 and miR-877-3p fine-tune regeneration. These mechanisms inform regenerative strategies aimed at controlling stem cell activation in skin and other tissues.
Comparative biology and livestock traits
In cashmere goats, miR-877-3p targeting IGFBP5 regulates the secondary hair follicle cycle, demonstrating that negative regulation of the hair cycle has agricultural and comparative biology relevance. Such studies provide models for understanding conserved and species-specific mechanisms of hair cycle suppression.
From negative regulation of hair cycle-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of TREM2 alter hair follicle stem cell quiescence? | TREM2 knockout mouse |
| Does Oncostatin M overexpression inhibit hair growth? | OSM overexpression transgenic model |
| Is FGF5 required for suppression of hair elongation? | FGF5 knockout animal model |
| Does PD-1/PD-L1 signaling regulate anagen entry? | PD-1 or PD-L1 knockout mouse |
| Does miR-877-3p targeting of IGFBP5 affect hair follicle cycle? | miR-877-3p mimic/inhibitor in cashmere goat |
| Does DNA methylation of lncRNA2919 regulate hair follicle regeneration? | Epigenetic editing and lncRNA2919 knockout |
How to Study the negative regulation of hair cycle Process
| Method | What It Measures | Typical Application |
|---|---|---|
| RNA sequencing | Global transcriptome changes across hair cycle stages | Identifying negative regulators of hair cycling |
| Immunohistochemistry | Protein localization in skin and hair follicle | Mapping FGF-5 and FGF-5S distribution |
| Immunofluorescence | Co-localization of macrophage and stem cell markers | Studying TREM2+ macrophage-stem cell interactions |
| Macrophage-stem cell co-culture | Effect of secreted factors on stem cell quiescence | Testing Oncostatin M-mediated inhibition |
| MicroRNA mimic/inhibitor assays | Functional impact of microRNAs on hair follicle cycle | Validating miR-877-3p targeting of IGFBP5 |
| DNA methylation analysis | Epigenetic regulation of lncRNA expression | Studying lncRNA2919 in hair follicle regeneration |
| Hair cycle staging histology | Anagen, catagen, and telogen phase distribution | Assessing PD-1/PD-L1 effects on hair cycle transition |
Transcriptomic profiling of hair follicle cycle stages
RNA sequencing of skin or hair follicle samples across anagen, catagen, and telogen stages can identify genes and non-coding RNAs that are enriched during negative regulation of the hair cycle. Such profiling has revealed miR-877-3p and lncRNA2919 as regulators of hair follicle cycling and regeneration.
Immunohistochemistry and immunofluorescence
Localization studies using immunohistochemistry and immunofluorescence have identified FGF-5 protein in skin macrophage-like cells and FGF-5S protein in hair follicles, supporting their roles in hair growth cycle regulation. These methods are essential for mapping the cellular sources of negative regulators such as Oncostatin M.
Macrophage-stem cell co-culture and cytokine assays
Co-culture systems with TREM2+ dermal macrophages and hair follicle stem cells, combined with cytokine assays, can test whether macrophage-derived factors such as Oncostatin M maintain stem cell quiescence and inhibit hair growth. Neutralizing antibodies and recombinant proteins are used to establish causality.
Epigenetic and non-coding RNA perturbation
DNA methylation inhibitors, lncRNA knockdown, and microRNA mimic/inhibitor experiments can dissect epigenetic and non-coding RNA contributions to negative regulation of the hair cycle. These approaches have been applied to lncRNA2919 and miR-877-3p in hair follicle regeneration and secondary hair follicle cycling.
How CRISPR Can Be Used to Study GO:0042636 negative regulation of hair cycle
Knockout
CRISPR knockout of candidate negative regulators such as TREM2, OSM, or FGF5 can test whether their loss accelerates hair follicle cycling or promotes anagen entry. Knockout models provide causal evidence for gene function in negative regulation of the hair cycle.
Point Mutation
Point mutations can be introduced into signaling domains of FGF5 or immune checkpoint genes to dissect structure-function relationships in hair cycle suppression. Such models help distinguish loss-of-function from dominant-negative effects.
Knock-in
Knock-in of reporter tags or disease-associated variants into loci such as TREM2 or OSM enables tracking of expression and function during hair cycle stages. Tagged knock-in models facilitate imaging and biochemical studies of negative regulators.
Overexpression
Overexpression of Oncostatin M, FGF5, or lncRNA2919 can directly test whether increased levels suppress hair follicle cycling and maintain quiescence. Overexpression models are valuable for validating gain-of-function mechanisms in negative regulation of the hair cycle.
How EDITGENE Supports negative regulation of hair cycle Research
Researchers studying negative regulation of hair cycle-related genes often need to determine whether a candidate gene is causally involved in suppressing hair follicle cycling or is merely correlated with quiescence. EDITGENE provides end-to-end CRISPR services to generate precisely engineered cell and animal models that answer these causal questions.
Contact EDITGENE today to design your custom CRISPR model for negative regulation of hair cycle research.
Frequently Asked Questions About negative regulation of hair cycle
What is negative regulation of hair cycle (GO:0042636)?
GO:0042636 is a biological process term defined as any process that stops, prevents, or reduces the frequency, rate, or extent of the cyclical phases of growth (anagen), regression (catagen), quiescence (telogen), and shedding (exogen) in the life of a hair.
What genes are involved in negative regulation of hair cycle?
Key genes include TREM2, OSM, FGF5, PD-1, PD-L1, IGFBP5, and non-coding RNAs such as miR-877-3p and lncRNA2919, based on published studies.
How do TREM2+ macrophages inhibit hair growth?
A subset of TREM2+ dermal macrophages secretes Oncostatin M to maintain hair follicle stem cell quiescence and inhibit hair growth.
What is the role of FGF5 in the hair cycle?
FGF5 is a secreted signaling protein that acts as a dominant inhibitor of hair elongation and is a well-established negative regulator of the hair cycle across mammals.
Does the PD-1/PD-L1 pathway affect hair cycling?
Yes, the PD-1/PD-L1 pathway has been implicated in murine hair cycle transition and is described as a potential anagen phase regulator.
How do microRNAs regulate the hair follicle cycle?
miR-877-3p targets IGFBP5 to regulate the secondary hair follicle cycle in cashmere goats, demonstrating microRNA-mediated control of hair cycling.
What is the role of DNA methylation in hair follicle regeneration?
DNA methylation mediates lncRNA2919 regulation of hair follicle regeneration, showing that epigenetic modifications contribute to hair follicle cycling control.
Which experimental models are used to study negative regulation of hair cycle?
Common models include TREM2 knockout mice, OSM overexpression models, FGF5 knockout animals, PD-1/PD-L1 knockout mice, and miR-877-3p perturbation in cashmere goats.
How can CRISPR help study negative regulation of hair cycle?
CRISPR knockout, point mutation, knock-in, and overexpression models allow causal testing of candidate genes such as TREM2, OSM, and FGF5 in hair follicle cycling.
Why is negative regulation of hair cycle important for medicine?
It governs the balance between hair follicle activation and quiescence, which is relevant to hair loss disorders, immune checkpoint therapy side effects, and regenerative medicine.
Conclusion
Negative regulation of the hair cycle (GO:0042636) is a biologically and clinically important process that integrates immune, secreted factor, checkpoint, and epigenetic signals to suppress hair follicle cycling. Key regulators such as TREM2+ macrophage-derived Oncostatin M, FGF5, PD-1/PD-L1, miR-877-3p, and lncRNA2919 provide a foundation for mechanistic studies and therapeutic targeting. CRISPR-based models are indispensable for establishing causality in this field, and EDITGENE offers comprehensive knockout, point mutation, knock-in, overexpression, library screening, and bioinformatics services to accelerate research on negative regulation of the hair cycle.
References
- 1. Wu C et al.. 2023. Regulation of secondary hair follicle cycle in cashmere goats by miR-877-3p targeting IGFBP5 gene.. J Anim Sci 101 PMID: 37777862
- 2. Carrion EA et al.. 2024. FGF5.. Differentiation 139:100736 PMID: 37957094
- 3. Wang ECE et al.. 2019. A Subset of TREM2(+) Dermal Macrophages Secretes Oncostatin M to Maintain Hair Follicle Stem Cell Quiescence and Inhibit Hair Growth.. Cell Stem Cell 24(4):654-669.e6 PMID: 30930146
- 4. Zhou L et al.. 2021. The PD-1/PD-L1 pathway in murine hair cycle transition: a potential anagen phase regulator.. Arch Dermatol Res 313(9):751-758 PMID: 33399960
- 5. Zhao B et al.. 2022. DNA Methylation Mediates lncRNA2919 Regulation of Hair Follicle Regeneration.. Int J Mol Sci 23(16) PMID: 36012763
- 6. Qin T et al.. 2022. Sufu- and Spop-mediated regulation of Gli2 is essential for the control of mammalian cochlear hair cell differentiation.. Proc Natl Acad Sci U S A 119(43):e2206571119 PMID: 36252002
- 7. Suzuki S et al.. 1998. Localization of rat FGF-5 protein in skin macrophage-like cells and FGF-5S protein in hair follicle: possible involvement of two Fgf-5 gene products in hair growth cycle regulation.. J Invest Dermatol 111(6):963-72 PMID: 9856803
- 8. Torchinsky C et al.. 1999. Regulation of p27Kip1 during gentamicin mediated hair cell death.. J Neurocytol 28(10-11):913-24 PMID: 10900094
