PROBLEM TO BE SOLVED: To provide a new, safe, and highly effective substance capable of controlling atrogin-1 gene.SOLUTION: Provided is an expression suppressing medicine for atrogin-1 gene, which containins oyster.【課題】本発明は、安全で有効性の高いatrogin-1遺伝子を抑制できる新規な物質を提供する。【解決手段】カキを有効成分として含む、atrogin-1遺伝子の発現抑制剤。【選択図】図1