线粒体tRNA-Lys(T7719G)基因变异影响绵羊颗粒细胞凋亡生理机制研究  

Study on the Physiological Mechanism of Mitochondrial tRNA-Lys (T7719G)Gene Variation Affecting Apoptosis of Ovine Granulosa Cell

作　　者：吕世琪 周荣艳[1] 田树军[1] 陈晓勇[1] Lü Shiqi;ZHOU Rongyan;TIAN Shujun;CHEN Xiaoyong(College of Animal Science and Technology,Hebei Agricultural University,Baoding 071000,China)

机构地区：[1]河北农业大学动物科技学院,保定071000

出　　处：《畜牧兽医学报》2024年第5期2011-2021,共11页ACTA VETERINARIA ET ZOOTECHNICA SINICA

基　　金：河北省自然科学基金项目(C2020204001)。

摘　　要：本团队前期研究发现小尾寒羊线粒体tRNA-Lys基因(T7719G)变异与产羔数显著相关,并降低了颗粒细胞凋亡率,为此,开展了该变异影响颗粒细胞凋亡生理机制的研究。本研究选取G、T基因型绵羊各3只,屠宰后取卵巢组织培养颗粒细胞,颗粒细胞生理指标检测试验分为两组,每组3个重复,分别检测线粒体基因组拷贝数,线粒体呼吸酶复合物Ⅰ、复合物Ⅱ、复合物Ⅲ、复合物Ⅳ、复合物Ⅴ活性,线粒体耗氧量和胞外产酸能力、ROS产量、ATP水平和膜电位,以及tRNA-Lys总量和氨酰化水平,13个mtDNA编码多肽蛋白表达水平。结果表明,G基因型颗粒细胞线粒体拷贝数与T基因型差异极显著(P<0.01),为T基因型的1.78倍。G基因型细胞线粒体复合物Ⅲ活性是T型细胞的1.25倍(P<0.05),表明G基因型细胞氧化呼吸功能增强。G基因型颗粒细胞线粒体耗氧量、ATP偶联耗氧量比T基因型细胞分别提高了6.84%(P<0.05)和15.46%(P<0.01),G基因型细胞糖酵解能力显著降低(P<0.01),活性氧含量水平显著降低了34%,ATP含量明显上升,为T基因型的1.25倍(P<0.05),线粒体膜电位显著上升,为T基因型的1.24倍(P<0.01);G基因型细胞tRNA-Lys总量显著提高50%(P<0.01),氨酰化tRNA-Lys比例较T型细胞提高33.4%(P<0.01)。线粒体基因组编码的13个多肽(ND1、ND2、ND3、ND4、ND4L、ND5、ND6、CtyB、COⅠ、COⅡ、COⅢ、ATP6、ATP8)表达水平均显著提高(P<0.05)。初步解析了线粒体tRNA-Lys(T7719G)变异影响绵羊颗粒细胞凋亡的生理机制,即tRNA-Lys(T7719G)变异影响tRNA-Lys稳态和氨酰化水平,影响mtDNA编码的多肽翻译效率,同时引起拷贝数、ATP水平、ROS含量和部分酶活性变化,进而改变线粒体能量代谢功能和细胞凋亡。The previous studies have found that mitochondrial tRNA-Lys(T7719G)variation was associated with litter size,which decreased the apoptosis of granulosa cells in Small-tailed Han sheep.Therefore,the physiological mechanism of mitochondrial tRNA-Lys(T7719G)variation on granulosus cell apoptosis was explored.Three sheep were selected with G and T genotypes respectively,and slaughtered for ovarian tissue culture of granulosa cells.The detection experiment of granule cells physiological function were divided into two groups with 3 replicates in each group.Mitochondrial genome copy number,mitochondrial respiratory enzyme complexⅠ,complexⅡ,complexⅢ,complexⅣand complexⅤactivities were detected,respectively.Mitochondrial oxygen consumption and extracellular acid production capacity,ROS production,ATP level and membrane potential,as well as total tRNA-Lys and aminoacylation level,expression level of 13 mtDNA-encoded polypeptide proteins were detected.The results showed that the mitochondrial copy number of G genotype granulosa cells was significantly different from that of T genotype(P<0.01),which was 1.78 times that of T genotype.The activity of mitochondrial complex III in G genotype cells was 1.25 times higher than that in T type cells(P<0.05),indicating that the oxidative respiratory function of G genotype cells was enhanced.The mitochondrial oxygen consumption and ATP-coupled oxygen consumption of G genotype granulosa cells were 6.84%(P<0.05)and 15.46%(P<0.01)higher than those of T genotype cells,respectively.The glycolysis ability of G genotype cells was significantly decreased(P<0.01),the level of reactive oxygen species was significantly decreased by 34%,the ATP content was significantly increased,which was 1.25 times that of T genotype(P<0.05),and the mitochondrial membrane potential was significantly increased,which was 1.24 times that of T genotype(P<0.01).Total tRNA-Lys was significantly increased by 50%(P<0.01)in G genotype cells,and the proportion of amylated tRNA-Lys was increased by 33.4%(P<0.01)c

关 键 词：线粒体 tRNA-Lys基因 颗粒细胞 生理功能 

分 类 号：S826.3[农业科学—畜牧学]