期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2010
卷号:107
期号:8
页码:3412-3417
DOI:10.1073/pnas.0911262107
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:A new visualizing method was developed for monitoring protein-protein (P-P) interactions in live mammalian cells. P-P interactions are visualized by directing localization of a bait protein to endosomes. This method is sufficiently robust to analyze signal-dependent P-P interactions such as calcium-dependent protein interactions. We visualized interactions between activated calmodulin and calmodulin-binding proteins, and observed oscillatory interactions via time-lapse imaging. In addition, this new method can simultaneously monitor multiple P-P interactions in a single live cell, which allows comparison of interactions between several prey proteins and a single bait protein. We observed that CaMKK1 and CaMKII bind calmodulin with distinct binding affinities in live cell, which indicates that calcium signaling is fine-tuned by distinct activation patterns of CaM kinases. This method will enable investigation of cellular processes based on dynamic P-P interactions.
关键词:calmodulin-dependent kinase ; live cell imaging ; Protein-Protein interaction ; calcium ; small GTPase