目的探讨线粒体核糖体蛋白S5(mitochondrial ribosomal protein S5,MRPS5)对人膀胱癌细胞的增殖能力及其中干细胞干性特征的影响。方法 Western blot检测人膀胱癌及癌旁正常组织MRPS5的表达;构建靶向干扰MRPS5的慢病毒载体,感染膀胱癌...目的探讨线粒体核糖体蛋白S5(mitochondrial ribosomal protein S5,MRPS5)对人膀胱癌细胞的增殖能力及其中干细胞干性特征的影响。方法 Western blot检测人膀胱癌及癌旁正常组织MRPS5的表达;构建靶向干扰MRPS5的慢病毒载体,感染膀胱癌细胞株T24,以干扰Scramble序列作为对照,Western blot检测MRPS5干扰效率;细胞活力实验检测细胞增殖能力;流式细胞术检测细胞周期;细胞成球实验观察成球能力;Western blot检测肿瘤干性转录因子Nanog,Oct4,c-Myc和Sox2的表达;小鼠皮下移植瘤实验观察T24体内成瘤能力。结果 MRPS5在膀胱癌组织中的表达高于癌旁正常组织;慢病毒干扰载体PLKO.1-sh MRPS5有效,且干扰MRPS5表达后T24细胞增殖能力下降(P<0.05),周期阻滞于S期,干性因子表达均下调,成球率无变化(P>0.05)但成球直径明显减小;同时小鼠体内成瘤体积减小[(0.784±0.278)vs(0.500±0.245)cm3,P<0.05],瘤质量减轻[(0.862±0.372)vs(0.412±0.248)g,P<0.05]。结论 MRPS5在膀胱癌中较高表达,且干扰MRPS5表达能抑制T24增殖并抑制T24中的干细胞生物学特征。展开更多
The mitochondrial respiratory chain comprises 85 subunits, 13 of which are mitochondrial encoded. The synthesis of these 13 proteins requires many nuclear- encoded proteins that participate in mitochondrial DNA replic...The mitochondrial respiratory chain comprises 85 subunits, 13 of which are mitochondrial encoded. The synthesis of these 13 proteins requires many nuclear- encoded proteins that participate in mitochondrial DNA replication, transcript production, and a distinctive mitochondrial translation apparatus. We report a patient with agenesis of corpus callosum, dysmorphism, and fatal neonatal lactic acidosis with markedly decreased complex I and IV activity in muscle and liver and a generalized mitochondrial translation defect identified in pulse- label experiments. The defect was associated with marked reduction of the 12S rRNA transcript level likely attributed to a nonsense mutation in the MRPS16 gene. A new group of mitochondrial respiratory chain disorders is proposed, resulting from mutations in nuclear encoded components of the mitochondrial translation apparatus.展开更多
文摘The mitochondrial respiratory chain comprises 85 subunits, 13 of which are mitochondrial encoded. The synthesis of these 13 proteins requires many nuclear- encoded proteins that participate in mitochondrial DNA replication, transcript production, and a distinctive mitochondrial translation apparatus. We report a patient with agenesis of corpus callosum, dysmorphism, and fatal neonatal lactic acidosis with markedly decreased complex I and IV activity in muscle and liver and a generalized mitochondrial translation defect identified in pulse- label experiments. The defect was associated with marked reduction of the 12S rRNA transcript level likely attributed to a nonsense mutation in the MRPS16 gene. A new group of mitochondrial respiratory chain disorders is proposed, resulting from mutations in nuclear encoded components of the mitochondrial translation apparatus.