Cyclin Dependent Kinase 5 (Cdk5) is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Cyclin-dependent kinase 5 (CDK5) is a proline-directed serine/threonine kinase that plays critical roles in neuronal development, synaptic plasticity, and neurodegeneration1.
Unlike other CDKs, CDK5 is not involved in cell cycle regulation but instead functions primarily in post-mitotic neurons2.
¶ Gene and Protein
- Gene Symbol: CDK5
- Chromosomal Location: 7q36.1
- Protein Family: CDK family (CMGC group)
- Molecular Weight: 33 kDa
CDK5 requires binding to regulatory subunits for activity3:
- p35: Primary neuronal activator, creates CDK5/p35 complex
- p39: Neuronal-specific activator, expressed in later development
- p25: Truncated form of p35, generated by calpain cleavage, leads to hyperactive CDK54
- Controls neuronal migration during cortical development5
- Regulates axon guidance and dendrite formation
- Essential for cerebellar development
- Modulates synaptic vesicle release6
- Regulates AMPA and NMDA receptor trafficking
- Involved in long-term potentiation (LTP) and depression (LTD)
- Phosphorylates tau and other microtubule-associated proteins7
- Regulates actin cytoskeleton
- Controls neuronal morphology
CDK5 is hyperactive in AD brain8:
- p25 accumulation leads to constitutive CDK5 activation9
- Hyperactive CDK5 phosphorylates tau at multiple AD-relevant sites10
- Contributes to Amyloid-Beta toxicity
- Promotes synaptic loss
- CDK5 phosphorylates alpha-synuclein
- Involved in dopaminergic neuron death
- Linked to MPTP-induced parkinsonism
- Regulates TDP-43 pathology
- Contributes to motor neuron degeneration
- Huntington's Disease: Altered mutant huntingtin phosphorylation
- Frontotemporal Dementia: Linked to tau pathology
- Traumatic brain injury: Exacerbates neuronal damage
- Cleaves p35 to p259
- p25 stable, leads to prolonged CDK5 activation
- Causes mitochondrial dysfunction
- Triggers apoptotic pathways
- Oxidative stress activates calpain
- Creates feed-forward loop of neurodegeneration
- Roscovitine: Inhibits CDK5 along with other CDKs
- CYC202 (Seliciclib): Pan-CDK inhibitor
- Specific inhibitors: DN-289, compound 56 are being developed
- Brain penetration
- Selectivity over other CDKs
- Toxicity concerns
The study of Cyclin Dependent Kinase 5 (Cdk5) 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.
- Cruz JC, Tsai LH. A Jekyll and Hyde role of cyclin-dependent kinase 5 in brain development and disease. Genes Dev. 2004;18(24):2937-2940.
- Shah K, Lahiri DK. Cdk5 activity in the brain - multiple paths in neuronal development. Neuromolecular Med. 2014;16(4):761-774.
- Cheung ZH, Ip NY. Cdk5: a multifaceted kinase in neurodegenerative diseases. Trends Cell Biol. 2012;22(3):169-175.
- Liu SL, Wang C, Jiang Y, et al. The Role of Cdk5 in Alzheimer's Disease. Molecules. 2018;23(12):3173.
- Binder LI, Guillozet-Bongaarts AL, Garcia-Sierra F, et al. Tau, tangles and neurodegeneration. Curr Alzheimer Res. 2005;2(3):269-283.
- Patrick GN, Zukerberg L, Nikolic M, et al. Conversion of p35 to p25 deregulates Cdk5 activity and promotes neurodegeneration. Nature. 1999;402(6762):615-622.
- Lee MS, Kwon YT, Li M, et al. Neurotoxicity induces cleavage of p35 to p25 by calpain. Nature. 2000;405(6784):360-364.
- Ahlijanian MK, Barrezueta NX, Liu RD, et al. Hyperphosphorylated tau and cycin-dependent kinase 5 in Alzheimer's Disease. Proc Natl Acad Sci U S A. 2000;97(6):2910-2915.
- Takahashi S, Saito T, Hisanaga S, et al. Tau phosphorylation by Cdk5 and its role in neuronal dysfunction. J Neurochem. 2011;119(1):1-4.
- Johnson GV, Stoothoff WH. Tau phosphorylation in neuronal cell function and dysfunction. J Cell Sci. 2004;117(Pt 24):5721-5729.
🔴 Low Confidence
| Dimension |
Score |
| Supporting Studies |
10 references |
| Replication |
0% |
| Effect Sizes |
25% |
| Contradicting Evidence |
0% |
| Mechanistic Completeness |
75% |
Overall Confidence: 39%