E3 ubiquitin ligase HRD1 modulates the circadian clock through regulation of BMAL1 stability
E3 ubiquitin ligase HRD1 modulates the circadian clock through regulation of BMAL1 stability
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E3 泛素连接酶 HRD1 通过调节 BMAL1 稳定性来调节生物钟
DOI：
10.3892/etm.2020.8988
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发表时间：
2020-09-01
影响因子：
2.7
通讯作者：
Ren, Haigang
中科院分区：
文献类型：
--
作者：
Guo, Dongkai;Zhu, Yao;Ren, Haigang
昼夜节律在许多生理功能中起着重要作用。昼夜节律振荡是由分子水平上的生物钟组成的。生物钟的精确性由转录-翻译负反馈环以及时钟蛋白的翻译后修饰（包括泛素化）控制;然而，E3连接酶对时钟蛋白泛素化的影响需要进一步研究。免疫共沉淀和免疫荧光定位结果表明，滑膜蛋白1基因编码的内质网跨膜E3泛素连接酶HRD 1与脑和肌肉ARNT样1（BMAL 1）相互作用，增强BMAL 1蛋白的泛素化。此外，Western blotting和逆转录-定量PCR结果表明，HRD 1促进了K48相关的BMAL 1的多聚泛素化，从而通过泛素-蛋白酶体系统介导了BMAL 1的降解。此外，基因敲低和基因过表达分析表明，HRD 1依赖的BMAL 1蛋白降解调节BMAL 1靶基因的表达和哺乳动物细胞中昼夜节律振荡的幅度。目前的研究结果表明，HRD 1可能通过调节BMAL 1的稳定性来影响昼夜节律的调节。
Circadian rhythm serves an essential role in numerous physiological functions. Circadian oscillations are organized by circadian clock components at the molecular level. The precision of the circadian clock is controlled by transcriptional-translational negative feedback loops, as well as post-translational modifications of clock proteins, including ubiquitination; however, the influence of E3 ligases on clock protein ubiquitination requires further investigation. The results of co-immunoprecipitation and immunofluorescent localization, indicated that the endoplasmic reticulum transmembrane E3 ubiquitin ligase HRD1, encoded by the synoviolin 1 gene, interacted with brain and muscle ARNT-like 1 (BMAL1) and enhanced BMAL1 protein ubiquitination. In addition, the results of western blotting and reverse transcription-quantitative PCR suggested that HRD1 promoted K48-associated polyubiquitination of BMAL1 and thus mediated its degradation via the ubiquitin-proteasome system. Furthermore, gene knockdown and gene overexpression assays revealed that HRD1-dependent degradation of BMAL1 protein regulated the expression of BMAL1 target genes and the amplitude of circadian oscillations in mammalian cells. The findings of the current study indicate that HRD1 may influence the regulation of circadian rhythm via modulation of BMAL1 stability.