低氧状态下Apak对rRNA转录的调控  

Regulation of transcription of rRNA synthesis by Apak under hypoxic conditions

作　　者：王进龙[1] 尹钰[1] 王红叶[1] 王建[1,2] 田春艳[1,2] 

机构地区：[1]北京放射与辐射医学研究所蛋白质组学国家重点实验室,北京100850 [2]蛋白质药物国家工程研究中心,北京102206

出　　处：《军事医学》2017年第5期363-366,372,共5页Military Medical Sciences

基　　金：国家自然科学基金资助项目(31270799);国家科技合作专项资助项目(2014DFB30020)

摘　　要：目的探讨低氧状态下Kruppel相关盒(KRAB)型锌指蛋白Apak对核糖体RNA(rRNA)转录影响变化及机制。方法利用实时定量PCR检测低氧状态下rRNA转录水平的变化及Apak对rRNA转录水平的影响,Western印迹检测蛋白的表达,间接免疫荧光观察低氧状态下Apak的定位变化。结果在低氧(0.3%O2)处理24 h内,野生型HCT116细胞rRNA表达水平呈现先高后低的变化,而在Apak敲除的HCT116细胞系中,低氧处理后rRNA转录水平持续下降;低氧处理3 h后,Apak对rRNA转录的抑制能力消失,Apak的蛋白水平和磷酸化水平降低,在细胞核仁中的定位消失。结论低氧处理后Apak对rRNA转录抑制能力的消失促使rRNA转录水平的暂时升高。Objective To explore the effect and mechanism of Kruppel-assoeiated box（KRAB） type zinc-finger protein Apak on the transcription of ribosomal RNA （rRNA） under hypoxie conditions. Methods Real-time quantitative PCR （qRT-PCR） was used to detect the level of rRNA and the effect of Apak on the transcription of rRNA. The expression and phosphorylation level of proteins were examined by Western blotting. Immunofluorescence assay was used to observe the location of Apak. Results Under hypoxia （0.3 % 02 ） , the transcription level of rRNA increased first and then decreased in Apak wild type cells. In Apak knock-out cells, the transcription level of rRNA kept decreasing under hypoxic conditions. The repression of Apak on rRNA synthesis and the nueleolus location of Apak disappeared, and the expression and phosphorylation level of Apak were down-regulated under hypoxic conditions for 3 h. Conclusion Under hypoxie conditions, the disapperanee of Apak repression on rRNA transcription could lead to a temporary increase in rRNA.

关 键 词：Apak 基因 rRNA 低氧 

分 类 号：Q78[生物学—分子生物学]