### ME3 Gene Overview

**Gene Symbol**: ME3  
**Gene Name**: Malic enzyme 3  
**Function**: The ME3 gene encodes a mitochondrial NADP(+)-dependent malic enzyme that catalyzes the oxidative decarboxylation of (S)-malate to pyruvate, utilizing NADP+ as a cofactor. This reaction plays a crucial role in energy metabolism and cellular respiration.  

### 1. Associated Genes
While specific genes associated with ME3 are not always readily available, it is known to interact with various metabolic pathways. Here are some genes and proteins that may have functional or regulatory connections with ME3:
- **ME1 (Malic enzyme 1)**: Another malic enzyme that is cytosolic and NADP(+)-dependent.
- **ME2 (Malic enzyme 2)**: Mitochondrial isoform that is NAD(+)-dependent.
- **MDH1 (Malate dehydrogenase 1)**: Participates in the citric acid cycle, balancing malate levels.
- **PDHA1 (Pyruvate dehydrogenase E1 component)**: Links pyruvate metabolism with the citric acid cycle.
- **G6PD (Glucose-6-phosphate dehydrogenase)**: Involved in the pentose phosphate pathway, affecting the availability of NADPH, which can indirectly impact ME3 activity.

### 2. Aging and Age-related Diseases
- **Aging**: Studies have suggested that enzymes like ME3 may play a role in metabolic adaptations associated with aging. Alterations in energy metabolism can affect the accumulation of age-related cellular damage.
- **Age-related Diseases**: Malic enzymes including ME3 have been implicated in conditions associated with oxidative stress, such as neurodegenerative diseases (e.g., Alzheimer's and Parkinson's disease). The balance between NADPH production (via ME3) and oxidative stress may influence cellular longevity and the risk of age-related pathology.

### 3. Drug or Drug Classes
While there isn't a specific drug that targets ME3 directly, the enzyme is related to several metabolic pathways, and general interactions can be inferred:
- **Antioxidants**: Drugs targeting oxidative stress might indirectly affect ME3 function.
- **Metformin and other antidiabetic drugs**: These may influence metabolic pathways where ME3 is involved, particularly regarding glucose metabolism.
- **NAD+/NADP+ modulators**: Compounds that affect the concentrations of these cofactors might indirectly interact with the activity of malic enzymes.

### 4. Pathways and Biological Processes
ME3 is involved in several important metabolic pathways and biological processes:
- **Tricarboxylic Acid (TCA) Cycle**: ME3 participates by converting malate to pyruvate, aiding in the recycling of NADP+ and pyruvate utilization.
- **Aerobic Respiration**: The enzyme helps link carbohydrate metabolism with energy production.
- **Biosynthesis of Amino Acids**: ME3 may also play a role in synthesizing amino acids by providing intermediates.
- **Regulation of Metabolism**: The enzyme's function is crucial in maintaining metabolic homeostasis, especially in tissues requiring high levels of energy (e.g., heart, brain).

This overview reflects known functions and data related to the ME3 gene and highlights its importance in cellular metabolism and potential implications in health and disease. Further research is required to fully elucidate its roles and interactions.