Send to

Choose Destination
Methods. 2018 May 1;140-141:40-51. doi: 10.1016/j.ymeth.2018.02.002. Epub 2018 Feb 13.

Quantifying membrane protein oligomerization with fluorescence cross-correlation spectroscopy.

Author information

Department of Chemistry, University of Akron, Akron, OH 44325, USA.
Food Animal Health Research Program, Ohio Agriculture Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, OH 44691, USA.
Department of Biology, University of Akron, Akron, OH 44325, USA.
Department of Chemistry, University of Akron, Akron, OH 44325, USA. Electronic address:


Fluorescence cross-correlation spectroscopy (FCCS) is an advanced fluorescence technique that can quantify protein-protein interactions in vivo. Due to the dynamic, heterogeneous nature of the membrane, special considerations must be made to interpret FCCS data accurately. In this study, we describe a method to quantify the oligomerization of membrane proteins tagged with two commonly used fluorescent probes, mCherry (mCH) and enhanced green (eGFP) fluorescent proteins. A mathematical model is described that relates the relative cross-correlation value (fc) to the degree of oligomerization. This treatment accounts for mismatch in the confocal volumes, combinatoric effects of using two fluorescent probes, and the presence of non-fluorescent probes. Using this model, we calculate a ladder of fc values which can be used to determine the oligomer state of membrane proteins from live-cell experimental data. Additionally, a probabilistic mathematical simulation is described to resolve the affinity of different dimeric and oligomeric protein controls.


Dimerization; FRET; Fluorescence correlation spectroscopy; Fluorescence cross-correlation spectroscopy; Live cell fluorescence; Membrane protein dimerization

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center