### PPP2R2B Gene Overview

**Gene Symbol:** PPP2R2B  
**Gene Type:** Protein-coding gene  
**Location:** Chromosome 4

### 1. Associated Genes
While the NCBI and UniProt summaries focus primarily on PPP2R2B, it is also associated with several other genes, particularly those involved in the PP2A complex and signaling pathways. Associates may include:

- **PPP2CA:** Catalytic subunit of protein phosphatase 2A.
- **PPP2R1A:** A regulatory subunit involved in the formation of the PP2A holoenzyme complex.
- **PPP2R2A:** Another regulatory subunit related to PPP2R2B.
- **TSC1** and **TSC2:** Genes involved in the regulation of mTOR, which can be influenced by PP2A activity.
- **CDKN1A (p21):** A cyclin-dependent kinase inhibitor influenced by phosphatase activity which has implications in cell cycle regulation and aging.

### 2. Aging and Age-Related Diseases
The PPP2R2B gene is implicated in several aging processes and age-related diseases predominantly due to its role in cellular growth and apoptosis. Alterations in PPP2R2B expression and function may contribute to:

- **Neurodegenerative diseases:** Mutations in PPP2R2B lead to SCA12, which can manifest in mid-age and is characterized by cerebellar degeneration. 
- **Cancer:** Given that PP2A is a tumor suppressor, dysregulation of PPP2R2B may contribute to tumorigenesis as well, particularly in the context of age-related cancers.
- **Cellular senescence:** Altered function of PP2A in the regulation of the cell cycle can contribute to cellular senescence, a hallmark of aging tissues.

### 3. Drug Interactions
While specific drugs targeting PPP2R2B directly may not be prevalent, the PP2A complex is a target for several classes of drugs, particularly in the context of cancer therapy. Examples include:

- **Pharmacological agents that activate PP2A:** Such as FTY720 and certain small molecule activators, which may help restore the function in contexts like cancer therapeutics.
- **Inhibitors of signaling pathways:** Some drugs that target the PI3K/Akt/mTOR pathway (e.g., rapalogs) could indirectly influence pathways regulated by the PP2A complex.
- **Cyclic peptides** that can interact with PP2A may also modify the interaction between PPP2R2B/PP2A and its substrates.

### 4. Pathways and Biological Processes
PPP2R2B is involved in several critical signaling pathways and biological processes, including:

- **Cell Cycle Regulation:** By modulating the activity of cyclin-dependent kinases and other cell cycle proteins.
- **Apoptosis:** Regulating pro-apoptotic signaling pathways relevant for neuronal survival and response to cellular stress.
- **Neuronal signaling:** Involved in the regulation of neurotransmitter release and synaptic plasticity.
- **Mitochondrial dynamics:** Modulates the balance of mitochondrial fission and fusion, thus influencing cellular energy metabolism and apoptosis.

In summary, the PPP2R2B gene plays a crucial role in the regulation of cellular processes affecting growth, survival, and metabolism, with important implications for neurodegeneration and potentially age-related diseases.