Kang Lihua, Zhao Weijie, Zhang Guowei, Wu Jian, Guan Huaijin
Eye Institute, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China.
Eye Institute, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China; Department of Ophthalmology, First People's Hospital of Changshu City, Affiliated Hospital of Soochow University, Changshu, Jiangsu Province, China.
Exp Eye Res. 2015 Jun;135:102-8. doi: 10.1016/j.exer.2015.02.005. Epub 2015 Feb 7.
The human 8-oxoguanine-DNA glycosylase 1 (OGG1) is the major DNA glycosylase responsible for repair of 7,8-dihydro-8-oxoguanine (8-oxoG) and ring-opened fapyguanine, critical mutagenic DNA lesions that are induced by reactive oxygen species. OGG1 acetylation has been demonstrated playing an important role in response to DNA damage. Here, we investigated the relationship between acetylated OGG1 (Ac-OGG1) and ARC, and clarified the effect of p300 and SIRT1 on the 8-oxoG excision ability of OGG1 in ARC development. Our results showed that anterior lens capsules from ARC group had higher proportion of 8-oxoG positive LECs than those from control group. OGG1 mRNA and protein levels significantly increased in ARC group compared with control group, while the protein levels of Ac-OGG1 were lower in ARC group. We investigated the factors involved in OGG1 acetylation and found that p300 and SIRT1 are the major acetyltransferases for OGG1 acetylation. We also identified acetylation of K338/K341 lysine residues in OGG1 has an important role on the repair activity of OGG1 to oxidative damage after H2O2 exposure in human lens epithelial cells (HLE-B3). Taken together, these data demonstrate that OGG1 acetylation regulates its function in response to DNA damage and could be one of the mechanisms of ARC.
人类8-氧代鸟嘌呤-DNA糖基化酶1(OGG1)是负责修复7,8-二氢-8-氧代鸟嘌呤(8-氧代鸟嘌呤)和开环的fapy鸟嘌呤的主要DNA糖基化酶,这些是由活性氧诱导产生的关键诱变DNA损伤。OGG1乙酰化已被证明在应对DNA损伤中发挥重要作用。在此,我们研究了乙酰化OGG1(Ac-OGG1)与ARC之间的关系,并阐明了p300和SIRT1在ARC发生过程中对OGG1的8-氧代鸟嘌呤切除能力的影响。我们的结果显示,ARC组的前囊膜中8-氧代鸟嘌呤阳性晶状体上皮细胞(LEC)的比例高于对照组。与对照组相比,ARC组中OGG1的mRNA和蛋白质水平显著增加,而ARC组中Ac-OGG1的蛋白质水平较低。我们研究了参与OGG1乙酰化的因素,发现p300和SIRT1是OGG1乙酰化的主要乙酰转移酶。我们还确定,在人晶状体上皮细胞(HLE-B3)中,OGG1上K338/K341赖氨酸残基的乙酰化对H2O2暴露后OGG1对氧化损伤的修复活性具有重要作用。综上所述,这些数据表明OGG1乙酰化调节其对DNA损伤的反应功能,可能是ARC的机制之一。