Cdk4 Protein is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
CDK4 (Cyclin-Dependent Kinase 4) is a serine/threonine kinase that forms a complex with D-type cyclins to regulate cell cycle progression from G1 to S phase. CDK4 is essential for cell proliferation and is frequently dysregulated in cancer. In the nervous system, CDK4 plays important roles in neuronal development, cell cycle re-entry in neurodegeneration, and synaptic plasticity .
| Attribute |
Value |
| Gene Symbol |
CDK4 |
| Protein Name |
Cyclin-Dependent Kinase 4 |
| Alternative Names |
CDK4, PSK-J3 |
| UniProt ID |
P11802 |
| Molecular Weight |
~34 kDa |
| Protein Family |
CDK family |
| Tissue Distribution |
Broad, high in proliferating cells |
CDK4 has typical CDK structure:
- Kinase domain — Serine/threonine kinase activity
- Cyclin-binding domain — Binds D-type cyclins (CYCD1-3)
- TPX2 binding site — Regulatory interactions
- Thr172 phosphorylation site — Activation loop
CDK4 activity requires:
- Binding to D-type cyclins
- Phosphorylation at Thr172 by CDK-activating kinase (CAK)
- Removal of inhibitory phosphorylation
CDK4/Cyclin D complex:
- G1 progression — Phosphorylates RB to release E2F
- Gene expression — Enables S-phase gene transcription
- Cellular commitment — Commit cells to proliferation
- Restriction point — Controls G1/S transition
In neurons:
- Development — Required for neurogenesis
- Cell cycle control — Post-mitotic neurons exit cell cycle
- Synaptic plasticity — Regulates synaptic protein synthesis
- Memory formation — Activity-dependent cell cycle re-entry
CDK4 is critically involved in AD:
- Cell cycle re-entry — Post-mitotic neurons re-enter cell cycle
- Aβ toxicity — Aβ induces CDK4 activation
- Tau phosphorylation — CDK4 can phosphorylate tau
- Neuronal death — Aberrant cell cycle leads to apoptosis
CDK4 inhibitors are being explored for AD treatment .
- Cell cycle dysregulation — Activated in PD brains
- Dopaminergic neuron loss — Contributes to neurodegeneration
- α-Synuclein toxicity — May interact with α-synuclein pathway
- Ischemic injury — CDK4 activated after stroke
- Therapeutic potential — CDK4 inhibitors may be neuroprotective
CDK4 is a therapeutic target:
- Cancer therapy — CDK4/6 inhibitors (palbociclib, ribociclib)
- Neurodegeneration — CDK4 inhibitors for AD and PD
- Combination therapy — May enhance other treatments
- PMID:8125168 — Discovery of CDK4
- PMID:8286351 — CDK4/Cyclin D structure
- PMID:10625657 — CDK4 in cell cycle
- PMID:15857886 — CDK4 in neuronal functions
- PMID:18559509 — CDK4 in Alzheimer's disease
- PMID:21479819 — CDK4 inhibition for neurodegeneration
The study of Cdk4 Protein 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.