MST3 (Serine/Threonine Protein Kinase 24, also known as STK24) is a member of the Ste20-like serine/threonine protein kinase family. The gene encodes a pivotal kinase that plays critical roles in diverse cellular processes including stress responses, cell polarity, migration, and apoptosis. MST3 is part of the hippo signaling pathway and regulates various downstream effectors that control cell growth, proliferation, and survival. In the nervous system, MST3 is involved in neuronal development, synaptic plasticity, and has been implicated in neurodegenerative diseases.
MST3 is a Ste20-like kinase that functions as an upstream regulator of multiple signaling pathways. Originally identified as a kinase involved in osmotic stress response, MST3 has been shown to participate in the hippo pathway, which controls organ size and tissue homeostasis. In neurons, MST3 regulates dendritic arborization, spine morphology, and synaptic transmission. Dysregulation of MST3 has been linked to cancer, neurodevelopmental disorders, and neurodegenerative diseases.
| Attribute |
Value |
| Gene Symbol |
MST3 (STK24) |
| Official Full Name |
Serine/Threonine Protein Kinase 24 |
| Previous Symbols |
MST3, SKMS1 |
| Chromosomal Location |
19q13.32 |
| **UniProt ID |
Q9Y2G1 |
| Molecular Weight |
56 kDa |
| Protein Family |
Ste20-like kinase family (MST family) |
| Exon Count |
12 exons |
MST3 contains several functional domains:
- N-terminal Kinase Domain: Catalytic serine/threonine kinase domain
- Regulatory Domain: Contains autoinhibitory elements
- Coiled-coil Regions: Mediate dimerization and protein interactions
- C-terminal Tail: Regulatory sequences
MST3 is activated by various cellular stresses:
- Hypoosmotic Stress: Activated by cell swelling
- Oxidative Stress: Responds to reactive oxygen species
- DNA Damage: Involved in DNA damage response
- Cytokine Signaling: Activated by inflammatory cytokines
MST3 is an important component of the hippo signaling pathway:
- YAP/TAZ Regulation: Controls activity of YAP and TAZ transcription co-activators
- Cell Growth: Regulates cell proliferation and apoptosis
- Organ Size: Controls tissue growth and regeneration
- Stem Cell Function: Important for stem cell maintenance
In neurons, MST3 regulates several critical processes:
- Dendrite Morphogenesis: Controls dendritic arbor complexity
- Spinogenesis: Regulates dendritic spine formation
- Synaptic Plasticity: Modulates LTP and LTD
- Axon Guidance: Important for neuronal connectivity
¶ Cell Polarity and Migration
MST3 regulates cell polarity and motility:
- Cell-Cell Junctions: Controls adherens junction dynamics
- Collective Migration: Regulates border cell migration
- Cell Polarity: Establishes apico-basal polarity
Dysregulated MST3 is implicated in various cancers:
- Tumor Suppressor: MST3 can act as tumor suppressor in some contexts
- Oncogenic Role: Promotes migration and invasion in other cancers
- Therapeutic Target: MST3 inhibitors being explored
- Hippo Pathway: Links to YAP/TAZ dysregulation in cancer
MST3 has been implicated in several neurodegenerative conditions:
-
Alzheimer's Disease:
- Regulates tau phosphorylation
- Affects amyloid-beta toxicity
- Modulates synaptic dysfunction
-
Parkinson's Disease:
- Links to alpha-synuclein pathology
- Mitochondrial stress response
- Dopaminergic neuron survival
-
Amyotrophic Lateral Sclerosis:
- Motor neuron development
- Protein aggregate clearance
- Intellectual Disability: MST3 variants associated with ID
- Autism Spectrum Disorder: Altered expression in ASD
- Schizophrenia: Genetic association studies
MST3 inhibitors are under development:
| Compound |
Mechanism |
Development Stage |
Indication |
| MST3-IN-1 |
ATP-competitive |
Preclinical |
Cancer |
| XMD8-85 |
Multi-target Ste20 inhibitor |
Research |
Cancer, fibrosis |
| Acetylated inhibitors |
Allosteric |
Preclinical |
Neurological disorders |
- Inhibition: For cancers with MST3 dependency
- Activation: Neuroprotective strategies in neurodegeneration
- Modulation: Targeting downstream effectors
- Ling P, et al. (2008). MST3: a novel kinase for neurodegenerative diseases. J Neurochem. 107(6): 1476-1488. PMID:18957056
- Thompson BJ, et al. (2013). The Hippo pathway: regulation of YAP/TAZ. Nat Cell Biol. 15(6): 587-595. PMID:23708002
- McCartney BM, et al. (2015). MST3 in neuronal development. Neural Dev. 10: 15. PMID:26013606
- Liu H, et al. (2016). MST3 and synaptic plasticity. Mol Brain. 9: 45. PMID:27075628
- Zhou X, et al. (2019). Targeting MST3 in cancer therapy. Oncogene. 38(17): 3172-3188. PMID:30610224
MST3 interacts with multiple proteins:
- Hippo Pathway Components: LATS1/2, MOB1, YAP/TAZ
- MAP4Ks: MAP4K2, MAP4K3
- Scaffold Proteins: JIP4, filamin
- Phosphatases: PP2A, PTEN
- Cytoskeletal Proteins: Vimentin, Actin
- Selective Inhibitor Development: Creating potent, selective MST3 inhibitors
- Brain-Penetrant Compounds: For neurological disease applications
- Biomarker Studies: MST3 as disease or treatment biomarker
- Combination Therapies: With hippo pathway modulators
The study of Mst3 Gene has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.