### Overview of the PLXNA4 Gene

**Gene Symbol**: PLXNA4  
**Location**: Encoding a protein that acts as a coreceptor for semaphorin, particularly SEMA3A, PLXNA4 is involved in critical processes related to axon guidance and serves important roles in the nervous system's development.

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### 1. Associated Genes
PLXNA4 is known to interact with multiple other genes primarily involved in neuronal signaling and development. Some of these include:
- **SEMA3A**: Semaphorin 3A, which directly binds to PLXNA4 as a signaling molecule.
- **NPRs (Neuropilins)**: Specifically, neuropilin-1 (NPN1) and neuropilin-2 (NPN2) are known partners in forming semaphorin receptor complexes.
- **PTPRZ1**: Protein tyrosine phosphatase receptor type Z1 may interact in pathways involving nervous system development.
- **RHOA/Rac1/Cdc42**: Rho GTPases that are regulated by the signaling pathways activated by PLXNA4, impacting cytoskeleton dynamics.

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### 2. Aging and Age-Related Diseases
Research suggests that PLXNA4, through its roles in cellular signaling, may be implicated in age-related neurodegenerative conditions. Key points include:
- **Neurodegeneration**: Abnormal semaphorin signaling could contribute to conditions such as Alzheimer's disease, where proper neuronal connectivity and communication are essential.
- **Axon Maintenance**: As aging progresses, defects in axon guidance and regeneration may lead to diminished neuronal functionality; PLXNA4 may play a role in maintaining the integrity of neuronal networks with age.

While there is limited direct association data available, its involvement in these processes suggests potential implications for aging and disease.

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### 3. Drug Interactions
Currently, there are no specific drugs or drug classes directly targeted at PLXNA4 reported in approved therapeutics. However, it may have indirect associations due to its functional involvement in signaling pathways. Drug interactions could include those targeting related pathways or upstream signaling molecules such as:
- **Semaphorin pathway inhibitors or modulators**: These could indirectly affect PLXNA4's function.
- **Small molecules that modulate Rho GTPase signaling**: Given the involvement of RHOA/Rac1/Cdc42 in signaling downstream of PLXNA4.

Further investigation and clinical studies would be necessary to identify specific drug interactions.

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### 4. Pathways and Biological Processes
PLXNA4 is associated with multiple biological pathways and processes, including but not limited to:
- **Axon Guidance**: Vital for proper neuronal pathway formation during development.
- **Cytoskeleton Rearrangement**: Regulation of cytoskeletal dynamics in response to external signaling (e.g., semaphorins).
- **Nervous System Development**: Involved in the structural formation of the nervous system.
- **Regulation of GTPase Activity**: Modulating the activity of Rho family GTPases critical to cellular signaling and structure.

Additionally, PLXNA4 can be implicated in broader pathways such as:
- **Neurotrophin signaling**: Interacting indirectly with neurotrophic factors to influence neuron survival and differentiation.
- **Signal Transduction Pathways**: Mechanisms involving various receptors affecting cellular responses to environmental cues.

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Overall, PLXNA4 serves a crucial role in neuronal development and may have significant implications for understanding neurodegenerative diseases and developing targeted therapies. Further research will shed light on the intricate relations this gene has with aging and associated disorders.