### METTL1 Gene Overview

**Gene Symbol:** METTL1 (Methyltransferase Like 1)

**Function:** The METTL1 gene encodes a protein that functions as a catalytic component of the METTL1-WDR4 methyltransferase complex. This complex is responsible for the methylation of guanine residues to form N7-methylguanine in various RNA species, including tRNAs, mRNAs, and microRNAs. 

### 1. Associated Genes
While specific lists of associated genes are not always available, METTL1 is known to collaborate with several other genes and complexes involved in RNA metabolism and methylation. These include:
- **WDR4:** A general partner in the METTL1-WDR4 complex that facilitates the RNA methylation activity.
- Other methyltransferases, particularly those involved in similar pathways, such as **METTL3** and **METTL14**, which are part of the m6A methylation machinery.
- Several miRNAs, notably **let-7**, which is directly methylated by METTL1. 

### 2. Aging and Age-related Diseases
Research has indicated that METTL1 may have implications in aging processes and age-related diseases due to its role in RNA metabolism and regulation of stem cell dynamics. Specific findings include:
- **Stem Cell Function:** It has been observed that METTL1 regulates the self-renewal and differentiation of embryonic stem cells, suggesting a possible involvement in tissue regeneration and aging.
- **Cancer:** Abnormal expression or mutations in METTL1 might contribute to oncogenic processes, which are closely tied to aging and longevity.

### 3. Drug Interactions
While there aren't universally defined drugs that directly target METTL1, there are indications that:
- Drugs targeting RNA metabolism, including certain antiviral and anti-cancer therapies, could indirectly influence the activity of METTL1 by modifying RNA pathways.
- **General classes:** Antivirals that disrupt RNA processing could affect the stability and methylation of mRNAs, potentially involving pathways linked with METTL1.

### 4. Pathways and Biological Processes Involvement
METTL1 is involved in several critical biological processes and signaling pathways, including:
- **tRNA Methylation:** Specifically catalyzing the m7G46 modification in tRNAs, which is essential for proper tRNA function and stabilization.
- **mRNA Regulation:** Involved in N7-methylguanine methylation of mRNAs that is critical for translation regulation.
- **MicroRNA Processing:** Direct involvement in the maturation of select microRNAs, including let-7, which is crucial for developmental timing and cellular differentiation.
- **Embryonic Development:** Plays a role in stem cell self-renewal and differentiation, thus is implicated in developmental biology.

**Key Pathways:**
- **RNA processing and modification pathways**
- **Methylation-related pathways** in cellular processes
- **Stem cell maintenance pathways** that influence differentiation and self-renewal

In summary, METTL1 is a pivotal gene involved in RNA methylation with essential roles in RNA stability, translation, and cellular differentiation. Its functions underscore significant biological pathways related to development and potential implications in aging and diseases.