Sodium Iodate-Induced Mouse Model of Age-Related Macular Degeneration Displayed Altered Expression Patterns of Sumoylation Enzymes E1, E2 and E3
Sodium Iodate-Induced Mouse Model of Age-Related Macular Degeneration Displayed Altered Expression Patterns of Sumoylation Enzymes E1, E2 and E3
复制标题
碘酸钠诱导的年龄相关性黄斑变性小鼠模型显示苏酰化酶 E1、E2 和 E3 的表达模式发生改变
DOI：
10.2174/1566524019666190112101147
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发表时间：
2018
影响因子：
2.5
通讯作者：
David Wan-Cheng Li
中科院分区：
文献类型：
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作者：
Qian Nie;Xiaodong Gong;Lili Gong;Lan Zhang;Xiangcheng Tang;Ling Wang;Fangyuan Liu;Jia-Ling Fu;Jia-Wen Xiang;Yuan Xiao;Zhongwen Luo;Ruili Qi;Zhigang Chen;Yunfei Liu;Qian Sun;Wenjie Qing;Lan Yang;Jie Xie;Ming Zou;Yuwen Gan;Huimin Chen;David Wan-Cheng Li
目的：蛋白质类小泛素化是一种高度动态的可逆的翻译后修饰，涉及小泛素样修饰物（SUMO）与靶蛋白的赖氨酸残基的共价缀合。与泛素化类似，SUMO化由E1、E2和几种E3连接酶催化。然而，类小泛素化通常不引起蛋白质降解，而是通过多种机制改变靶功能。越来越多的证据表明，类小泛素化在人类疾病的发病机制中起着关键作用，包括神经元变性、癌症和心脏病等。然而，SUMO化机制的表达在正常和致病性视网膜中尚未被表征。年龄相关性黄斑变性（age-related macular degeneration，AMD）是世界范围内导致老年人不可逆性失明的主要原因。本研究观察了正常小鼠和碘酸钠诱导的AMD小鼠模型中主要SUMO化酶的表达。方法：选用4周龄C57 BL/6 J小鼠。在PBS中由固体NaIO 3新鲜制备无菌1%NaIO3溶液。给实验小鼠注射70 mg/kg NaIO 3，并注射相似体积的PBS作为对照。摘除眼睛并浸入FAA固定过夜，并处理眼睛横截面。固定后，将横截面眼脱水，包埋在石蜡中，并使用旋转式切片机切割6 mm横截面。石蜡切片HE染色，观察视网膜厚度，评价组织病理学改变。结果：治疗后1天，注射NaIO 3的小鼠RPE中E1、E2和E3连接酶PIAS 1的RNA水平显著下降。因此，PIAS 1的蛋白水平在该时间点也降低。在治疗后期（注射后3天），在注射NaIO 3的小鼠视网膜中检测到E1酶SAE 1/UBA 2的表达显著降低。相反，E3连接酶RanBP 2在注射视网膜中显著增加。结论：总之，我们的研究结果首次证明了氧化应激诱导的视网膜变性进展过程中sumoylation途径酶的动态表达。E1、E2和E3酶在RPE和视网膜变性过程中的动态表达揭示了SUMO化在AMD发病机制中的潜在调节作用。
Purpose: Protein sumoylation is a highly dynamic and reversible post-translational modification, involving covalently conjugation of the small ubiquitin-like modifier (SUMO) to the lysine residue of the target protein. Similar to ubiquitination, sumoylation is catalyzed by E1, E2 and several E3 ligases. However, sumoylation usually does not cause protein degradation but alter the target function through diverse mechanisms. Increasing evidences have shown that sumoylation plays pivotal roles in the pathogenesis of human diseases, including neuron degeneration, cancer and heart disease, etc. We and others have shown that sumoylation is critically implicated in mouse eye development. However, the expression of sumoylation machinery has not been characterized in normal and pathogenic retina. Worldwide, age-related macular degeneration (AMD) is the leading cause of irreversible blindness in aged person. In the present study, we investigated the expression of the major sumoylation enzymes in normal mice and sodium iodateinduced AMD mouse model...Methods: Four-week-old C57BL/6J mice were used in our experiment. A sterile 1% NaIO3 solution was freshly prepared in PBS from solid NaIO3. Experimental mice were injected with 70 mg/kg NaIO3, and similar volumes of PBS as control. Eyes were enucleated and immersion in FAA fixation overnight and processed for eye cross-sections. After fixation, cross sections eyes were dehydrated, embedded in paraffin, and 6 mm transverse sections were cut using the rotary microtome. Then paraffin sections were stained with hematoxylin and eosin (H&E), and mouse retinal thickness was observed to assess the histopathologic changes...Results: Significantly declined RNA levels of E1, E2 and E3 ligase PIAS1 in NaIO3-injected mouse RPE one day-post treatment. Consistently, the protein level of PIAS1 was also decreased at this time point. At the late stage of treatment (three days post-injection), significantly reduced expression of E1 enzyme SAE1/UBA2 was detected in NaIO3-injected mouse retinas. In the contrary, dramatically increased E3 ligase RanBP2 was found in the injected-retinas...Conclusion: Together, our results demonstrated for the first time the dynamic expression of sumoylation pathway enzymes during the progression of retina degeneration induced by oxidative stress. Dynamic expression of E1, E2 and E3 enzymes were found during the time course of RPE and retina degeneration, which revealed the potential regulatory roles of sumoylation in AMD pathogenesis.