Super-resolution imaging and tracking of protein–protein interactions in sub-diffraction cellular space

• Published in: Nature communications 2014-07, Vol.5 (1), p.4443-4443, Article 4443
• Main Authors: Liu, Zhen, Xing, Dong, Su, Qian Peter, Zhu, Yun, Zhang, Jiamei, Kong, Xinyu, Xue, Boxin, Wang, Sheng, Sun, Hao, Tao, Yile, Sun, Yujie
• Format: Article
• Language: English
• Subjects: 14/35; 14/63; 631/337/475/2290; 631/80/2373; 639/624/1107/328; Cell Wall - metabolism; Escherichia coli - metabolism; Escherichia coli Proteins - metabolism; HeLa Cells; Humanities and Social Sciences; Humans; multidisciplinary; Peptide Elongation Factor Tu - metabolism; Protein Binding; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms5443

Imaging the location and dynamics of individual interacting protein pairs is essential but often difficult because of the fluorescent background from other paired and non-paired molecules, particularly in the sub-diffraction cellular space. Here we develop a new method combining bimolecular fluorescence complementation and photoactivated localization microscopy for super-resolution imaging and single-molecule tracking of specific protein–protein interactions. The method is used to study the interaction of two abundant proteins, MreB and EF-Tu, in Escherichia coli cells. The super-resolution imaging shows interesting distribution and domain sizes of interacting MreB–EF-Tu pairs as a subpopulation of total EF-Tu. The single-molecule tracking of MreB, EF-Tu and MreB–EF-Tu pairs reveals intriguing localization-dependent heterogonous dynamics and provides valuable insights to understanding the roles of MreB–EF-Tu interactions. Protein–protein interactions are ubiquitous in cells and these contacts are crucial for a wide number of cellular processes. Here, the authors present a technique for the super-resolution imaging and tracking of protein–protein interactions in cells.