To the Editor:
In their correspondence in Nature Methods, Adler et al. claim to present the first high-resolution topography of plasma membranes in living cells1. Using hopping-probe ion conductance microscopy (HPICM), they show that the plasma membrane contains many subresolution membrane folds and point out serious implications for single-particle tracking studies. We fully underwrite this conclusion and would like to point out that subresolution wrinkling also has serious implications for other, more mainstream, imaging techniques.
We reported in 2002 a simple approach to visualize plasma membrane topography with nanometer precision2,3 (Supplementary Fig. 1). Whereas HPICM equipment is sparsely available, our approach requires only a confocal microscope with precise focus-stepping capacity. In full accordance with the data of Adler and co-workers1, we showed that plasma membranes contain many subresolution wrinkles. We also showed that subresolution membrane folds should be considered when interpreting lateral fluorescence enrichments at the plasma membrane. For example, apparent microdomains intensely decorated with lipid probes have been interpreted to reflect lateral probe enrichment. However, our results indicated that they rather represent spots with high membrane content, that is, wrinkles in a homogenously labeled plasma membrane2. Perhaps the simplest and most effective approach to control for local membrane content is by normalizing the fluorescence intensity of probes of interest to that of a homogenously distributed membrane marker such as the carbocyanine dye DiI.
Note: Supplementary information is available on the Nature Methods website.
Adler, J., Shevchuk, A., Novak, P., Korchev, Y & Parmryd, I. Nat. Methods 7, 170–171 (2010).
Van Rheenen, J. & Jalink K. Mol. Cell. Biol. 13, 3257–3267 (2002).
Van Rheenen, J. & Jalink K. Imaging & Microscopy 4, 46–48 (2002).
This work was supported by a VIDI fellowship (91710330) and equipment grants (911-06-027 (K.J.) and 175.010.2007.007 (J.v.R.)) from the Dutch Organization of Scientific Research (NWO).
The authors declare no competing financial interests.
About this article
Cite this article
Jalink, K., van Rheenen, J. Nano-imaging of membrane topography affects interpretations in cell biology. Nat Methods 7, 486 (2010). https://doi.org/10.1038/nmeth0710-486
Analytical Chemistry (2020)
Science Signaling (2017)