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bioRxiv · 10.1101/2022.04.13.488239

Lossless end-to-end transport of small molecules through micron-length DNA nanochannels

Li, Y.·Maffeo, C.·Joshi, H.·Aksimentiev, A.·Menard, B.·Schulman, R.
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Abstract

Designed and engineered protein and DNA nanopores can sense and characterize single molecules and control transmembrane transport of molecular species. However, designed biomolecular pores are less than 100 nm in length and are used primarily for transport across lipid membranes. Nanochannels that span longer distances could be used as conduits for molecules between non-adjacent compartments or cells. Here, we design microns-long, 7 nm diameter DNA nanochannels that small molecules can traverse according to the laws of continuum diffusion. Binding DNA origami caps to channel ends eliminates transport and demonstrates that molecules diffuse from one channel end to the other rather than permeating through channel walls. These micron-length nanochannels can also grow, form interconnects, and interface with living cells. This work thus shows how to construct multifunctional, dynamic agents that control molecular transport, opening new ways of studying intercellular signaling and modulating molecular transport between synthetic and living cells. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=130 SRC="FIGDIR/small/488239v1_ufig1.gif" ALT="Figure 1"> View larger version (22K): org.highwire.dtl.DTLVardef@fec963org.highwire.dtl.DTLVardef@157bb83org.highwire.dtl.DTLVardef@d7a274org.highwire.dtl.DTLVardef@ea961c_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Li, Y., Maffeo, C., Joshi, H., Aksimentiev, A., Menard, B., Schulman, R.. 2022-04-14. Lossless end-to-end transport of small molecules through micron-length DNA nanochannels. https://doi.org/10.1101/2022.04.13.488239

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