CDC25C (Cell Division Cycle 25C) is a dual-specificity phosphatase that plays a critical role in cell cycle regulation by removing inhibitory phosphates from cyclin-dependent kinases (CDKs). While traditionally studied in the context of cancer and cell proliferation, emerging research reveals important functions in post-mitotic neurons and implications for neurodegenerative diseases[1].
CDC25C belongs to the CDC25 family of dual-specificity phosphatases, which also includes CDC25A and CDC25B. The protein consists of approximately 473 amino acids and contains a conserved catalytic domain that removes phosphate groups from tyrosine, serine, and threonine residues. CDC25C's primary function is to activate CDK1 (also known as Cdc2) by dephosphorylating inhibitory residues at Thr14 and Tyr15, thereby promoting G2/M transition during the cell cycle[2]. [1]
In post-mitotic neurons, abnormal cell cycle re-entry is a pathological feature of several neurodegenerative diseases. CDC25C expression and activity are dysregulated in Alzheimer's disease (AD) brains, where neurons attempt to re-enter the cell cycle but fail to complete mitosis, leading to neuronal dysfunction and death[1]. [2]
CDC25C participates in the DNA damage response checkpoint. Following DNA damage, CDC25C is phosphorylated and inhibited, preventing cell cycle progression to allow DNA repair. In neurodegenerative conditions, chronic DNA damage accumulation may lead to persistent CDC25C inhibition, contributing to neuronal stress[3]. [3]
Recent studies suggest CDC25C may have non-cycling functions at synapses, where it could regulate synaptic plasticity-related signaling pathways. The phosphatase may influence long-term potentiation (LTP) through modulation of synaptic kinase activities.
CDC25C is significantly upregulated in AD brain tissue, particularly in regions vulnerable to neurodegeneration like the hippocampus and prefrontal cortex. This upregulation correlates with cell cycle marker expression, suggesting neurons are attempting but failing to complete cell division. CDC25C inhibitors have been proposed as potential therapeutic agents to prevent aberrant neuronal cell cycle re-entry[1][4].
Alterations in CDC25C expression have been observed in Parkinson's disease models. The protein may interact with pathways controlling neuronal survival, including those involving cyclin-dependent kinases and protein phosphatases.
Emerging evidence suggests cell cycle dysregulation in ALS, with CDC25C potentially playing a role in motor neuron degeneration.
CDC25C represents a potential therapeutic target for neurodegenerative diseases. However, given its essential role in cell proliferation, systemic inhibition could have significant side effects. Brain-specific delivery methods or targeting downstream effectors may offer safer therapeutic approaches.
Kalous et al. CDC25 phosphatases in cell cycle control (2015). 2015. ↩︎
Schmitt et al. DNA damage response in neurodegeneration (2017). 2017. ↩︎
Moh et al. CDC25C in Alzheimer's disease (2011). 2011. ↩︎