### VPS26A Gene Overview

**Gene Symbol:** VPS26A  
**Function:** The VPS26A gene is part of the vacuolar protein sorting (VPS) family and encodes a protein that is a critical component of the retromer complex. This complex is essential for retrograde transport of proteins from endosomes back to the trans-Golgi network (TGN). VPS26A interacts with VPS35 and is involved in maintaining the proper sorting of transmembrane proteins, preventing their degradation in lysosomes.

### 1. Associated Genes

Besides VPS35, which is noted in the summaries, VPS26A is known to interact with several other genes. These include:

- **SNX3**: Involved in recruitment to the endosomal membrane and facilitating retrograde transport.
- **RAB7A**: A small GTPase that plays a role in trafficking between endosomes and lysosomes.
- **WASHC2A**: A member of the WASH complex that is important for actin polymerization and endosomal trafficking.
- **TBC1D5**: Involved in the regulation of small GTPases and trafficking.
- **SORL1**: Potentially involved in Alzheimer's disease pathology, as it is implicated in amyloid precursor protein sorting.

### 2. Aging and Age-Related Diseases

Research indicates that VPS26A may have a role in aging and age-related diseases:

- **Alzheimer’s Disease**: The retromer complex, involving VPS26A, is implicated in the sorting and trafficking of SORL1, relevant to the processing of amyloid precursor protein (APP), suggesting potential connections to Alzheimer's disease pathogenesis.
- **Neurodegeneration**: Impairments in retromer function, including those involving VPS26A, are associated with neurodegenerative conditions, which may be exacerbated with age, possibly due to increasing cellular stress and pathological protein accumulation.
- **Cellular Aging**: The role of retromer in protein recycling could suggest that disruptions in VPS26A function might impact cellular homeostasis, contributing to age-related decline in various cellular functions.

### 3. Drug Interactions

There are currently no specific drugs or drug classes directly known to interact with VPS26A listed in the available databases. However, because VPS26A is involved in critical pathways of lysosomal sorting and retrograde transport, compounds that target related pathways, such as those affecting endosomal trafficking or autophagy, may indirectly affect the functions of VPS26A. Further research is needed to clarify any specific pharmacological interactions.

### 4. Pathways and Biological Processes

VPS26A is involved in several key pathways and biological processes:

- **Vacuolar Protein Sorting**: Central to maintaining cellular protein homeostasis by facilitating the retrograde transport of proteins.
- **Endosomal Transport**: Participates in the trafficking and recycling of proteins from early endosomes back to the TGN as well as to the plasma membrane.
- **Regulation of Gene Expression**: VPS26A's interactions with other proteins can indirectly influence pathways involved in cellular responses to stress and gene expression.
- **Protein Recycling**: Participates in processes that regulate the cycling of receptors and other membrane proteins, contributing to cellular signaling and homeostasis.

In conclusion, as part of the retromer complex, VPS26A plays a vital role in intracellular transport and protein sorting, which are crucial for cellular health and function with implications in aging and neurodegenerative diseases. Further studies might reveal more detail about its interactions and potential therapeutic targets.