2021-01期目录

为研究团头鲂(Megalobrama amblycephala) 5-甲基胞嘧啶(5-methylcytosine, 5mC)羟基化酶TET1(Ten eleven translocation 1)基因的功能及其表达特性, 采用整胚原位杂交、qRT-PCR技术进行了胚胎、组织表达分析及其在急性低氧胁迫下的基因响应研究。序列分析结果表明, 团头鲂TET1基因全长为5526 bp, 编码1841个氨基酸。qRT-PCR结果表明, 团头鲂TET1广泛表达于各个组织中, 并在脑组织中高度表达。在胚胎发育过程中, TET1基因从受精卵开始就有表达, 并在受精后20—44h (20—44 hpf)都维持在一个较高水平。原位杂交结果表明, TET1基因在12 hpf信号相对微弱, 在24和36 hpf信号逐渐增强, 并且都集中在头部表达。通过qRT-PCR检测急性缺氧处理TET1的表达量, 结果表明, TET1基因在鳃和脾等组织中表达显著升高(P<0.01), 在脑、皮肤、眼和肾脏中表达显著降低(P<0.01)。在胚胎中, TET1基因相对表达量明显高于对照组, 尤其在24 hpf低氧处理组的表达量显著地高于对照组(P<0.001)。结果表明TET1基因在低氧应答反应中发挥着重要的作用。该研究结果为TET1基因在低氧响应及功能的保守与分化方面提供了新的视角。

THE EFFECT OF HYPOXIC STRESS ON TET1 EXPRESSION IN BLUNT SNOUT BREAM

Ten eleven translocation 1(TET1)protein is a 5—methylcytosine(5mC)hydroxylase.To study the functions and expression characteristics of TET1 gene in blunt snout bream(Megalobrama amblycephala),the whole mount in situ hybridization(WISH)and qRT-PCR technique were analyzed its expression in embryos and tissues and its response under acute hypoxic stress.Sequence analysis results showed that TET1 gene is 5526 bp,encoding 1841 amino acids.The qRT-PCR results demonstrated that TET1 gene was extensively expressed in tissues of blunt snout bream,especially in brain.During embryonic development,the TET1 gene was expressed from the fertilized egg and was maintained at a high level of 20—44h(20—44 hpf)after fertilization.The WISH analysis results suggested that TET1 signal was relatively weak at 12 hpf,and gradually enhanced at 24 and 36 hpf,especially in the head.Hypoxia significantly induced the expression of TET1 gene in gill,spleen,and other tissues(P<0.01),and significantly decreased its expression in brain,skin,eyes,and kidneys(P<0.01).Hypoxia also increased the expression of TET1 gene in embryos,especially in the 24 hpf hypoxia treatment group(P<0.001).The above results indicated that TET1 gene plays an important role in hypoxia response.This study provides a new perspective on the TET1 gene in terms of hypoxia response and functional conservation and differentiation.