### KLHDC2 Gene Overview

**Gene Symbol**: KLHDC2  
**Function**: KLHDC2 encodes a substrate-recognition component of a Cul2-RING E3 ubiquitin-protein ligase complex involved in the ubiquitin-dependent protein degradation process through the C-end degron rule pathway.

### 1. Associated Genes
KLHDC2 is primarily associated with other components of the Cul2-RING E3 ubiquitin ligase complex. While specific interactions or associations outside of the provided summary are not widely documented, the following genes may be linked through its role in ubiquitination and protein degradation:
- **SELENOK**: A selenoprotein that KLHDC2 recognizes for degradation.
- **SELENOS**: Another selenoprotein targeted by this ligase complex.
- **USP1**: The N-terminal fragment of this deubiquitinating enzyme is also recognized and degraded by KLHDC2.

### 2. Aging and Age-Related Diseases
Research on KLHDC2 in the context of aging is limited, but its role in protein degradation pathways may have implications for cellular health as organisms age.  
- **Protein Homeostasis**: Effective functioning of ubiquitin ligases is critical for protein quality control. Disruptions in these pathways are known to contribute to cellular senescence and age-related diseases such as neurodegeneration.
- **Potential Age-Related Pathologies**: While not explicitly studied, aberrant degradation processes linked to KLHDC2 may impact conditions such as cancer, where dysregulation of proteostasis is frequently observed.

### 3. Known Drug Interactions
Currently, there are no specific drugs or drug classes directly known to interact with KLHDC2. However, because KLHDC2 plays a role in the ubiquitin-proteasome pathway, treatments or interventions that modify ubiquitin ligase activities could indirectly influence its function. Further research will be needed to clarify any direct pharmaceutical implications.

### 4. Pathways and Biological Processes
KLHDC2 is implicated in several biological processes, including:
- **Ubiquitin-Dependent Protein Catabolic Process**: Facilitating the degradation of proteins marked for destruction.
- **C-End Degron Rule Pathway**: Recognizing C-terminal degrons for targeted degradation.
- **Nuclear Processes**: Functioning within nuclear bodies and membranes as part of cellular regulation.

### Summary
KLHDC2 is an essential component of the CRL2 E3 ubiquitin ligase complex, specifically involved in recognizing and mediating the degradation of proteins with C-terminal "diglycine" motifs. Its activity is central to various cellular functions, and while little is known about its direct connections to age-related diseases or drug interactions, it plays a crucial role in maintaining cellular proteostasis. Further research is warranted to explore its functions in aging and therapeutic contexts.