摘要
为探究敲除组蛋白去乙酰化酶8基因(histone deacetylase 8,hdac8)对斑马鱼(Danio rerio)低温耐受能力的影响,采用组织学、生理和生化等方法,研究了低温(8℃)短期胁迫下hdac8基因敲除(hdac8^(-/-))斑马鱼和野生型(WT)斑马鱼的组织损伤、氧化应激相关指标及其凋亡相关基因表达的变化。结果表明:低温胁迫下,hdac8^(-/-)斑马鱼的半数致死时间(LT50)明显缩短,hdac8^(-/-)斑马鱼的LT50为14.5 h,WT斑马鱼的LT50为21.5 h;HE染色显示,低温胁迫下,hdac8^(-/-)斑马鱼鳃丝、肝脏和骨骼肌相较于WT斑马鱼损伤更加严重;28℃下,WT和hdac8^(-/-)斑马鱼的活性氧(ROS)、丙二醛(MDA)水平无显著性变化(P>0.05),而hdac8^(-/-)斑马鱼的ATP水平则显著降低(P<0.05);低温胁迫下,hdac8^(-/-)斑马鱼的ROS和MDA水平显著高于WT斑马鱼(P<0.05),而ATP水平则显著低于WT斑马鱼(P<0.05);RT-qPCR显示,28℃下,hdac8^(-/-)斑马鱼caspase3基因表达显著上调(P<0.05),其他抗氧化与凋亡相关基因无显著性变化(P>0.05);低温胁迫下,WT和hdac8^(-/-)斑马鱼sod、cat、caspase3、caspase9和bax基因表达水平显著上调(P<0.05),且hdac8^(-/-)斑马鱼的这5种基因表达水平均显著高于WT斑马鱼(P<0.05)。研究表明,敲除hdac8基因显著降低了斑马鱼的低温耐受能力,并促进了低温氧化应激损伤和细胞凋亡。
To explore the effects of knocking out histone deacetylase 8 gene(hdac8)on low-temperature tolerance of zebrafish(Danio rerio),the changes in tissue damage of gill filaments,liver,and skeletal muscles,oxidative stress-related indices,and apoptosis-related gene(caspase3,caspase9,bcl-2,bax and bcl-2/bax)expression were detected in 8 months old hdac8 deficient(hdac8^(-/-))and wild type(WT)zebrafish exposed to low water-temperature of 8℃stress from 28℃to 18℃at a rate of 1℃/h and then to 8℃at a rate of 0.5℃/h by histological,physiological and biochemical methods and gene expression analysis.The results showed that the median lethal time(LT50)was significantly decreased under low temperature stress in hdac8^(-/-)zebrafish,with the LT50 of 14.5 h relative to the LT50 of 21.5 h in WT zebrafish.HE staining showed that more severe damage was observed in the gill filaments,liver and skeletal muscle in hdac8^(-/-)zebrafish compared with WT zebrafish under low temperature stress.The ATP level in hdac8^(-/-)zebrafish showed very significant decrease(P<0.05)at 28℃,without significant difference in the levels of reactive oxygen species(ROS)and malondialdehyde content between WT and hdac8^(-/-)zebrafish(P>0.05).Under low-temperature stress,however,the hdac8^(-/-)zebrafish had very significantly higher ROS and MDA levels than the WT zebrafish did(P<0.05),and very significantly lower ATP level than the WT zebrafish(P<0.05)did.RT-qPCR revealed that there was significantly up-regulated expression level of caspase3 in hdac8^(-/-)zebrafish(P<0.05)at 28℃,without significant difference in the expression levels of other antioxidant and apoptosis-related genes(P>0.05).Under low-temperature stress,the expression levels of sod,cat,caspase3,caspase9 and bax were found to be significantly up-regulated in both WT and hdac8^(-/-)zebrafish(P<0.05),significantly higher expression levels of these genes in hdac8^(-/-)zebrafish than those in WT zebrafish(P<0.05).In conclusion,hdac8 knockout significantly impaired the tolerance to low
作者
史雪灵
罗军涛
罗贝贝
韩兵社
张俊芳
SHI Xueling;LUO Juntao;LUO Beibei;HAN Bingshe;ZHANG Junfang(Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources,Ministry of Education,Shanghai Ocean University,Shanghai 201306,China;National Demonstration Center for Experimental Fisheries Science Education,Shanghai Ocean University,Shanghai 201306,China)
出处
《大连海洋大学学报》
CAS
CSCD
北大核心
2023年第6期964-971,共8页
Journal of Dalian Ocean University
基金
上海市科技兴农重点攻关项目[沪农科创字(2019)第1-2号]
国家自然科学基金面上项目(81770165)
上海市教委水产一流学科建设项目。
