PLAGL2对TTF-1结合SP-C基因启动子能力影响的研究  

Studyfor the Effec on Interaction Site of TTF-1 Modulating Surfactant Protein-C Gene Promoter Exerting by PLAGL2

作　　者：邓飞涛[1] 葛凉芳[1] 杨昀[1] 李彦旭[2] 柴新群[2] 

机构地区：[1]华中科技大学附属协和医院妇产科,武汉市430022 [2]华中科技大学附属协和医院肝胆外科,武汉市430022

出　　处：《医学分子生物学杂志》2012年第4期262-266,共5页Journal of Medical Molecular Biology

基　　金：国家自然科学基金（No.30971072）

摘　　要：目的研究甲状腺转录因子-1（thyroid transcription factor1，TTF-1）对表面活性蛋白C（pulmonary surfactant—asso—ciated protein C，SP-C）基因启动子的调控作用及多形性腺瘤样基因2（pleiomorphic adenoma gene like-2，PLAGL2）对TTF-1结合SP-C基因启动子能力影响。方法应用体外细胞共转染后荧光素酶报告基因活性值检测技术研究TTF-1对SP-C基因启动子转录活性的调控及PLAGL2的影响作用：利用凝胶电泳迁移实验（EMSA）研究TTF-1对SP-C基因启动子靶点的结合及PLAGL2的影响作用：应用实时荧光PCR技术检测PLAGL2、TTF-1、SP—C在人胚肺和成熟小鼠肺Ⅱ型上皮细胞中mRNA水平。结果TTF-1明显提高SP—C基因启动子荧光素酶活性值（P〈0.01）。而共转染PLAGL2后则明显降低SP—C基因启动子荧光素酶活性值（P〈0．01）；TTF-1能与同位素标记的SP—C基因启动子片段结合形成TTF-1-SP-CDNA蛋白复合物，PLAGL2则明显降低该蛋白复合物形成；TTF-1、SP-C基因mRNA水平随胚肺孕周逐渐升高，PLAGL2基因mRNA水平随胚肺孕周逐渐减少。结论在肺Ⅱ型细胞中TTF-1对SP—C基因表达具有促进作用，PLAGL2则对该作用产生明显抑制影响。To investigate the effect of pleiomorphic adenoma gene like-2 （PLAGL2） on the modulation of thyroid transcription factor （ TTF-1 ） to the surfactant protein-C （ SP-C ） promoter. Methods The modulation of TTF-1 to the transcriptional activity of the SP-C promoter and the effect of PLAGL2 on such modulation were determined by detecting the Luciferase activity after co- transfection. The binding of TTF-1 to the SP-C promoter and the effect of PLAGL2 on the binding were measured by site-directed mutagenesis and EMSA. The mRNA expression levels of PLAGL2, TTF-1 and SP-C were detected in the tape Ⅱ cells derived from the human embryo lung and mature mouse lung by real-time PCR. Results TTF-1 was found significantly increasing the luciferase ac- tivity of the SP-C promoter （P 〈0. 01 ） , which was inhibited by co-transfection with PLAGL2 （P 〈0. 01）. TTF-1 could combine the isotope-labeled segment of the SP-C promoter and form the TFF-1-SP-C DNA protein complex, which was significantly abrogated by PLAGL2. The mRNA ex-pression levels of TTF-1 and SP-C in type Ⅱ cells were gradually increased with gestational weeks, while those of PLAGL2 showed an opposite tendency. Conclusions TTF-1 can promote the expres- sion of SP-C in lung type Ⅱ cells, which can be greatly inhibited by PLAGL2

关 键 词：多形性腺瘤样基因2 甲状腺转录因子-1 SP-C基因启动子 荧光素酶活性检测 凝胶电泳迁移实验 实时荧光PCR 

分 类 号：R714.51[医药卫生—妇产科学] Q471[医药卫生—临床医学]