CACNG1 encodes the gamma-1 auxiliary subunit of L-type voltage-gated calcium channels in skeletal muscle, functioning as a regulatory protein that modulates calcium channel inactivation kinetics and calcium ion transmembrane transport 1. The protein is located at the sarcolemma and T-tubules, where it positively regulates muscle contraction through calcium channel regulation [GO annotations supported by 21]. Mechanistically, CACNG1 directly binds to and regulates calcium influx through voltage-gated calcium channels. Recent evidence demonstrates that galectin-3 impairs CACNG1 function by binding to the protein and inhibiting calcium influx, thereby reducing glucose-stimulated insulin secretion in pancreatic β-cells 3. CACNG1 deficiency phenocopies this inhibitory effect, confirming its critical role in calcium-dependent cellular processes 3. Clinically, CACNG1 expression changes associate with multiple pathophysiological states. The gene is downregulated in HER2+ metastatic breast cancer early progressors compared to long responders, suggesting potential prognostic value 4. CACNG1 plays a role in skeletal muscle atrophy mechanisms during spaceflight-induced microgravity 5 and aging-related vocal fold extracellular matrix remodeling 6. Additionally, CACNG1 variants associate with genetic susceptibility to stress-induced cardiomyopathy through adrenergic pathway dysregulation 7. These findings position CACNG1 as a therapeutic target for diabetes, muscle atrophy, and potentially cardiac dysfunction.