Effects of IκBα and its mutants on NF-κB and p53 signaling pathways
Effects of IκBα and its mutants on NF-κB and p53 signaling pathways作者机构:Institute of Laser Life Science South China Normal University Guangzhou 510631 Guangdong Province China Institute of Biology Engineering Jinan University Guangzhou 510632 Guangdong Province China
出 版 物:《World Journal of Gastroenterology》 (世界胃肠病学杂志(英文版))
年 卷 期:2006年第12卷第41期
页 面:6658-6664页
核心收录:
学科分类:0710[理学-生物学] 071010[理学-生物化学与分子生物学] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术]
基 金:the National Natural Science Foundation of China No. 60378043 and 30470494) the Natural ScienceFoundation of Guangdong Province No. 015012 and 04010394
主 题:Nuclear factor-κB Inhibitor of NF-κB alpha p53 Real-time QT-PCR
摘 要:AIM: To study the effects of IκBα and its mutants (IκBαM, IκBα3N, IκBαM44C) on NF-κB, p53 and their downstream target genes. The relationship of NF-κB, p53, and IκBα was further discussed. METHODS: pECFP-IκBα, pECFP-IκBαM (amino acides 1-317, Ser32, 36A), pECFP-IκBα243N (amino acides 1-243), pECFP-IκBα244C (amino acides 24±317), pEYFP-p65 and pp53-DsRed were constructed and transfected to ASTC-α-1 cells. Cells were transfected with pECFP-Cl as a control. 30 h after the transfection, location patterns of NF-κB, p53 and IκBα(IκBαM, IκBα243N, IκBα224C) were observed by a laser scanning microscope (LSM510/ConfoCor2, Zeiss). RNA extraction and reverse transcription were performed in cells transfected or co-transfected with different plasmids. Effects of IκBα and its mutants on the transprition level of NF-κB, NF-κB downstream target gene TNF-α, p53 and p53 downstream target gene Bax were observed by real time QT-PCR. In all experiments β-actin was reference. Results are expressed as the target/reference ratio of the sample divided by the target/reference ratio of the control. Different transfected cells were incubated with CCK-8 for 2 h in the incubator. Then the absorbance at 450 nm was measured by using a microplate reader. RESULTS: Cells that were transfected with p53- DsRed revealed a predominant nuclear localization. YFP-p65 mainly existed in the cytoplasm. Cells were transfected with CFP-IκBα, CFP-IκBαM, and CFP-IκBα243N respectively and revealed a predominant cytosolic localization. However, cells transfected of CFP-IκBα244C revealed a predominant nuclear localization. The rnRNA levels of p65, TNF-α, p53 and Bax in CFP-IκBα transfected cells did not change significantly, while in YFP-p65/CFP-IκBα co-transfected cells, IκBα decreased the transcription of p65 downstream gene TNF-α (2.24 ± 0.503) compared with the YFP-p65/ CFP-C1 co-transfected cells (5.08 ± 0.891) (P 〈 0.05). Phosphorylation defective IκBα (IκBαM) decreased the transcription levels of all the four g