Effect of HIRA deletion on gene expression in mouse skeletal muscle at 6 weeks of age. Mus musculus

We performed gene expression profiling by microarray using RNA extracted from the tibialis anterior of control and Hira myofiber-specific conditional knockout mice at 6 weeks of age. Hira is a histone chaperone responsible for replication-independent incorporation of histone variant H3.3 at actively transcribed loci. Conditional knockout of Hira in myofibers caused hypertrophy, degeneration, and increased the percentage of type I fibers. These results illustrate the physiological consequences of disrupting Hira-mediated chromatin assembly in myofibers. Overall design: 4 animals per group (control and Hira conditional knockout) hybridized in triplicate. RNA was extracted from the tibialis anterior muscle.

本研究以6周龄对照组与肌纤维特异性Hira条件性敲除（conditional knockout）小鼠的胫骨前肌提取的RNA为样本，通过微阵列（microarray）技术开展基因表达谱分析。Hira是一种组蛋白伴侣（histone chaperone），负责在活跃转录位点介导组蛋白变体H3.3的不依赖复制的整合。在肌纤维中条件性敲除Hira会引发肌肥大、肌肉变性，并提升I型肌纤维的占比。上述结果阐明了在肌纤维中破坏Hira介导的染色质组装所产生的生理效应。实验设计概况：每组（对照组与Hira条件性敲除组）各4只实验动物，样本均进行三次重复杂交。RNA提取自胫骨前肌组织。