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Biology subjects

Teodori, L.

Publications and source records attributed to Teodori, L..

2 recordsLinked to original sources

Nanoscale precise stamping of biomolecule patterns using DNA origami

Understanding the importance of ligand patterning in biological processes requires precise control over molecular positioning and spacing. While DNA origami structures offer nanoscale precision in biomolecule arrangement, their biological applications are limited by challenges related to their structural stability, scalability, and surface area. Here, we present a straightforward and rapid DNA origami stamping technique for transferring nanoscale oligonucleotide patterns onto surfaces, visualized using DNA-PAINT super-resolution microscopy to quantitatively assess the stamping efficiency and precision across different stamp types. Unlike traditional top-down methods that require specialized equipment, our technique provides an accessible, self-assembled platform for surface patterning, with versatility across various substrates via modifiable pattern-transfer oligonucleotides. We demonstrate reliable, efficient, and precise pattern transfer at single-molecule resolution, enabling new opportunities to study distance-dependent biological processes, including receptor activation, multivalent binding, and enzymatic cascades across broader spatial scales and different detection techniques. The use of the passivated surface limits non-specific interactions with unpatterned areas and enables control over the interaction between the biological target and the patterned biomolecules. Our method advances surface patterning by combining DNA nanotechnology with single-molecule imaging techniques, expanding access to cost-effective analytical approaches and potentially enabling multiplexed detection and live measurements.

bioengineering↗

Biased activation of the receptor tyrosine kinase HER2

HER2 belongs to the ErbB sub-family of receptor tyrosine kinases and regulates cellular proliferation and growth. Different from other ErbB receptors, HER2 has no known ligand. Activation occurs through heterodimerization with other ErbB receptors and their cognate ligands. This suggests several possible activation paths of HER2 with ligand-specific, differential response, which so far remained unexplored. Using single-molecule tracking and the diffusion profile of HER2 as a proxy for activity, we measured the activation strength and temporal profile in live cells. We found that HER2 is strongly activated by EGFR-targeting ligands EGF and TGF, yet with a distinguishable temporal fingerprint. The HER4-targeting ligands EREG and NRG{beta}1 showed weaker activation of HER2, a preference for EREG, and a delayed response to NRG{beta}1. Our results indicate a selective ligand response of HER2 that may serve as a regulatory element. Our experimental approach is easily transferable to other membrane receptors targeted by multiple ligands. HighlightsO_LIHER2 exhibits heterogeneous motion in the plasma membrane C_LIO_LIThe fraction of immobile HER2 correlates with phosphorylation levels C_LIO_LIDiffusion properties serve as proxies for HER2 activation C_LIO_LIHER2 exhibits ligand-specific activation strength and temporal profiles C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/519064v2_ufig1.gif" ALT="Figure 1"> View larger version (55K): org.highwire.dtl.DTLVardef@172415eorg.highwire.dtl.DTLVardef@21bf95org.highwire.dtl.DTLVardef@1a907aforg.highwire.dtl.DTLVardef@37a85a_HPS_FORMAT_FIGEXP M_FIG C_FIG

biophysics↗