G9a is essential for dendritic plasticity and is associated with neurological disorders. The possible relationship between age-related hearing loss and G9a expression in the auditory cortex has not been fully explored. This study aimed to understand the expression patterns of G9a-mediated histone methylations in the auditory cortex during aging. Using immunofluorescence and western blotting, we demonstrated that a significant reduction in G9a expression observed in the auditory cortex of 24-month-old rats compared to 3-month-old rats, was associated with remarkable hearing threshold elevation and hair cell loss. Correspondingly, histone H3 lysine 9 (H3K9) mono- and dimethylation (marked by H3K9me1 and H3K9me2, respectively), which were regulated by G9a activity, also evidently decreased during aging. These findings, which merit further investigation, suggest a possible association between G9a-mediated histone methylations and central age-related hearing disorders.

G9a 对树突可塑性至关重要，并且与神经系统疾病有关。与年龄相关的听力损失与听觉皮层中 G9a 表达之间的可能关系尚未得到充分探讨。本研究旨在了解衰老过程中听觉皮层中 G9a 介导的组蛋白甲基化的表达模式。使用免疫荧光和蛋白质印迹，我们证明与 3 个月大的大鼠相比，在 24 个月大的大鼠听觉皮层中观察到的 G9a 表达显着降低，与显着的听力阈值升高和毛细胞丢失有关。相应地，受 G9a 活性调节的组蛋白 H3 赖氨酸 9 (H3K9) 单和二甲基化（分别由 H3K9me1 和 H3K9me2 标记）在衰老过程中也明显降低。这些发现，