The GCN1 gene, located in the cytosol, encodes a protein that plays critical roles in cellular stress responses and translation quality control. Below are detailed responses to your requests:

### 1. Associated Genes:
While the NCBI and UniProt summaries mention EIF2AK4 (GCN2), EEF1A1 (eEF1A), ETF1 (eRF1), and RNF14/RNF25, other associated genes that GCN1 may interact with or influence indirectly include:
- **ATF4**: A transcription factor activated under stress that regulates amino acid metabolism and stress responses.
- **EIF4E**: Involved in cap-dependent translation and might be linked to amino acid sensing.
- **Abl1**: Involved in various signaling pathways that might interact with translation initiation processes.
- **MKNK1** and **MKNK2**: MAP kinase-interacting kinases that could be involved in stress response and regulation of translation.

### 2. Aging and Age-Related Diseases:
Although specific studies directly linking GCN1 to aging or age-related diseases may not be extensively described in literature, its functions in stress response and translational control suggest potential implications:
- **Inhibition of Translation**: Dysregulation of GCN1-mediated translational control may result in impaired cellular responses to stress, which is a hallmark of aging.
- **Cancer**: GCN1 is involved in quality control during translation, and mutations or dysregulation of genes functioning in this capacity have been noted in age-related cancers.
- **Neurodegeneration**: Stress responses mediated by GCN1 could have implications for neurodegenerative diseases, where cellular stress is a factor contributing to age-related pathologies.

### 3. Drug Interactions:
There are currently no specific drugs or drug classes directly linked to GCN1 in literature. However, the pathway involving eIF2 alpha phosphorylation might be associated with drug classes targeting the integrated stress response (ISR), such as:
- **mTOR inhibitors** (e.g., rapamycin): These influence cellular stress responses and amino acid availability.
- **Translation inhibitors** (e.g., aminoglycosides) that could indirectly affect pathways involving GCN1.
- **Anticancer agents** targeting translational control mechanisms in tumors may also intersect with the functions of GCN1.

### 4. Pathways and Biological Processes:
GCN1 is involved in several pathways and biological processes including:
- **Integrated Stress Response (ISR)**: Activation of the ISR through GCN1 leads to modulation of protein synthesis, particularly in response to amino acid starvation.
- **Translation Quality Control (TQC)**: Critical in ribosomal stalling and elimination of error-prone translation factors to ensure fidelity.
- **Cellular Response to Amino Acid Starvation**: GCN1 mediates responses that alter metabolism and gene expression in conditions of nutrient deprivation.
- **Ubiquitination and Proteolysis**: It directly interacts with RNF14 for the ubiquitination and degradation of stalled ribosome components, promoting cellular homeostasis.

GCN1’s diverse roles in cellular stress response, translational regulation, and interaction with various signaling pathways underlines its importance in both normal physiology and pathological states. Further research may elucidate more about its role in aging, drug interactions, and disease associations.