### PRKAG3 Gene Overview

**Gene Symbol**: PRKAG3  
**Function**: PRKAG3 encodes a regulatory subunit of AMP-activated protein kinase (AMPK), which plays a crucial role in energy homeostasis and metabolism, especially in skeletal muscle.

### 1. Associated Genes
While the summaries provided focus on the functions of PRKAG3 in the context of AMPK, it is also worth noting that PRKAG3 is associated with several other genes involved in energy metabolism and signaling. Some of these genes include:

- **PRKAA1** and **PRKAA2**: These encode the catalytic alpha subunits of AMPK, which work in conjunction with PRKAG3.
- **ACACB**: Encodes acetyl-CoA carboxylase beta, a key enzyme inhibited by AMPK.
- **HMGCR**: Encodes 3-hydroxy-3-methyl-glutaryl-CoA reductase, another key metabolic enzyme regulated by AMPK.
- **ULK1**: Encodes Unc-51 Like Autophagy Activating Kinase 1, which is involved in autophagy regulation influenced by AMPK signaling.
- **SIRT1**: A gene involved in metabolic regulation that can interact with AMPK signaling pathways.

### 2. Aging and Age-Related Diseases
Research indicates that AMPK, and by extension PRKAG3, is associated with longevity and age-related diseases:

- **Aging**: AMPK activation is linked with increased lifespan in various model organisms. It mediates metabolic stress responses that enhance cellular adaptability and survival.
- **Age-related diseases**: Dysregulation of AMPK activity has been implicated in conditions such as obesity, type 2 diabetes, and various neurodegenerative diseases. PRKAG3's role in energy metabolism suggests that alterations in its function could affect aging processes and the development of age-related diseases.

### 3. Drug Interactions
PRKAG3 and AMPK are involved in metabolic regulation, making them targets for several pharmacological agents:

- **Metformin**: A common drug for type 2 diabetes, metformin activates AMPK, which enhances glucose uptake and decreases gluconeogenesis.
- **AICAR (5-aminoimidazole-4-carboxamide ribonucleotide)**: A compound that acts as an AMPK activator used in research settings to study metabolic regulation.
- **Other potential agents**: Drugs targeting metabolic disorders functionally interact with AMPK pathways, such as thiazolidinediones and glucagon-like peptide-1 (GLP-1) agonists. 

### 4. Pathways and Biological Processes
PRKAG3 is involved in several key pathways and biological processes, including:

- **AMPK Signaling Pathway**: Central to energy homeostasis, regulating cellular metabolism in response to energy stress.
- **Regulation of Lipid Metabolism**: By inhibiting ACC and HMGCR, PRKAG3 influences fatty acid and cholesterol biosynthesis.
- **Autophagy**: AMPK activation promotes autophagy, a crucial cellular process for degrading and recycling cellular components.
- **Cell Growth Regulation**: Inhibits processes such as protein synthesis and cell growth in low energy states.
- **Insulin Signaling Pathway**: Modulates insulin sensitivity and glucose uptake in skeletal muscle.
- **Cellular Response to Stress**: Plays a role in how cells respond to metabolic and oxidative stress.

In summary, PRKAG3 is a pivotal gene in metabolic regulation, influencing energy homeostasis, cellular stress responses, and potentially the aging process, while being connected to numerous metabolic pathways and displaying interactions with various drugs.