EGFR, on the other hand, was imaged using a 1-plex approach. As a result, the EGF appears more intense in this figure than EGFR, even though the actual molecular ratio may not be skewed. Hope that answered your question! 2/2

Excellent question, Sahar!
The reason you're seeing more pink signal from EGF compared to the cyan EGFR signal is due to the imaging methods used in this figure. Specifically, we performed a 3-plex RESI experiment to label EGF. 1/2

Big shoutout to co-first authors, Isabelle Pachmayr and Larissa Heinze, for their incredible work and dedication. This work would not have been possible without Levent Bas, @lumasullo.bsky.social, Jisoo Kwon, Ana Perovic, Brenda Schulman, and Ralf Jungmann, as well as the
@jungmannlab.bsky.social!

The resolution of the newly developed RESI method allows us to quantify the clustering of EGF within the internalizations. This clustering is crucial for understanding how EGF initiates signaling pathways that regulate cell growth. 5/5

We could also observe EGF-EGFR clusters in 3D, capturing the internalization process of the ligand-receptor pair – down to a few nanometers! 4/5

Using this tag, we could visualize EGF-EGFR interactions in 2D, observing distinct clustering behavior of EGFR on the cell membrane. Additionally, we could identify EGFR dimers as well as the co-localization of EGFR and EGF. 3/5

We can study these tiny interactions by visualizing single molecules with DNA-PAINT. To image EGF, we tagged the ligand with a small peptide tag called ALFA-tag. 2/5

When ligands land on a cell’s surface, they interact with receptors, sparking a signal that travels to the cell’s control center: the nucleus. One key pair is the Epidermal Growth Factor Receptor (EGFR) and its ligand EGF. They play a crucial role in both cell growth and cancer. 1/5