### IL13RA1 Gene Summary

**Gene Symbol**: IL13RA1

**Function**: The IL13RA1 gene encodes a subunit of the interleukin-13 receptor, which forms a receptor complex primarily with the IL4 receptor alpha subunit. This receptor complex plays a crucial role in mediating the signaling pathways triggered by interleukin 13 (IL13) and interleukin 4 (IL4). The IL13RA1 protein preferentially binds IL13 and is involved in signaling pathways that activate various transcription factors, including STAT3 and STAT6. The protein has also been shown to interact with the tyrosine kinase TYK2, facilitating the downstream signaling cascade.

### Additional Information

1. **Associated Genes**:
   - **IL4RA**: Often pairs with IL13RA1 to form the interleukin-4/13 receptor complex.
   - **TYK2**: Interacts with IL13RA1 as part of the signaling pathway.
   - **IL2RG**: While IL13RA1 is an accessory protein to IL4 signaling, it does not replace IL2RG in enhancing IL2 binding.

2. **Aging and Age-Related Diseases**:
   - There is emerging evidence linking IL13RA1 with various age-related conditions, particularly those involving inflammation and immune response. Dysregulation of IL13 signaling can contribute to chronic inflammatory diseases such as asthma, allergic rhinitis, and other respiratory diseases which have higher prevalence in older populations. Research has indicated that variations in genes within the IL13 pathway might be associated with susceptibility to these conditions as individuals age.

3. **Drug Interactions**:
   - **Monoclonal antibodies targeting IL-13 or IL-4** include:
     - **Lebrikizumab**: An IL-13 inhibitor under investigation for asthma and other allergic conditions.
     - **Dupilumab**: A monoclonal antibody that blocks the IL-4 receptor, impacting both IL-13 and IL-4 pathways.
   - **Corticosteroids**: While not directly interacting with IL13RA1, steroids can influence the overall IL-13 signaling by modulating the expression of cytokines, including IL13RA1.

4. **Pathways and Biological Processes**:
   - **Cytokine signaling pathway**: IL13RA1 is crucial in mediating and transducing signals from IL-13 and IL-4, specifically contributing to immune responses, inflammation, and allergic responses.
   - **JAK-STAT signaling pathway**: This is a major pathway involving the activation of JAK kinases that phosphorylate and activate STAT proteins, leading to an array of biological effects including gene regulation.
   - **Th2 cell differentiation**: IL13RA1 is integral in the differentiation of T-helper cells, particularly Th2 cells, which are involved in allergic responses and asthma.

### Summary
The IL13RA1 gene encodes a critical component of interleukin-13 receptors involved in immune signaling and inflammation. Its interactions with related genes, its role in age-related diseases, and its involvement in drug action highlight its significance in immunology and possible therapeutic targets. Further research into IL13RA1 could elucidate its full role in health and disease across different age groups.