Photonic Gene Circuits by Optically Addressable siRNA-Au Nanoantennas

UCSF/UCB Joint Graduate Group in Bioengineering, Berkeley Sensor & Actuator Center, Department of Bioengineering, University of California-Berkeley , Berkeley, California, United States.
ACS Nano (Impact Factor: 12.88). 07/2012; 6(9):7770-80. DOI: 10.1021/nn301744x
Source: PubMed


The precise perturbation of gene circuits and the direct observation of signaling pathways in living cells are essential for both fundamental biology and translational medicine. Current optogenetic technology offers a new paradigm of optical control for cells; however, this technology relies on permanent genomic modifications with light-responsive genes, thus limiting dynamic reconfiguration of gene circuits. Here, we report precise control of perturbation and reconfiguration of gene circuits in living cells by optically addressable siRNA-Au nanoantennas. The siRNA-Au nanoantennas fulfill dual functions as selectively addressable optical receivers and biomolecular emitters of small interfering RNA (siRNA). Using siRNA-Au nanoantennas as optical inputs to existing circuit connections, photonic gene circuits are constructed in living cells. We show that photonic gene circuits are modular, enabling subcircuits to be combined on-demand. Photonic gene circuits open new avenues for engineering functional gene circuits useful for fundamental bioscience, bioengineering, and medical applications.

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    • "In demonstrating the potential of photonic gene circuits, Lee et al. showed that two AuNR antenna populations functionalized with small interfering RNA (siRNA) could differentially release siRNA and thus turn gene circuits ‘off’ or ‘on’ upon excitation with light at one nanorod population's resonance wavelength [36]. However, there was some release of siRNA from the nanorod antenna population that was non-resonant at the light wavelength illuminating the cells [36]. This crosstalk suggests the potential importance of developing methods to fabricate NPs with narrower resonances and considering possible spectral changes in a cellular environment when designing the plasmon resonance characteristics of NP antennas. "
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    • "In particular, external laser excitation of nanoparticles can trigger payload release [6], [7], so nanoparticles can act as handles for controlling biological processes. Gold nanorods (NRs) have gained considerable interest for therapeutic applications because they can be selectively excited where tissue is transparent to release multiple species that can impact complex processes [6], [8]–[10] so they have many advantages for controlling blood clotting. "
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