Biology subjects

Bachelet, I.

Publications and source records attributed to Bachelet, I..

3 recordsLinked to original sources

bioRxiv2018

Nanoscale robots exhibiting quorum sensing

Multi-agent systems demonstrate the ability to collectively perform complex tasks--e.g., construction1-2, search3, and locomotion4,5--with greater speed, efficiency, or effectiveness than could a single agent alone. Direct and indirect coordination methods allow agents to collaborate to share information and adapt their activity to fit dynamic situations. A well-studied example is quorum sensing (QS), a mechanism allowing bacterial communities to coordinate and optimize various phenotypes in response to population density. Here we implement, for the first time, bio-inspired QS in robots fabricated from DNA origami, which communicate by transmitting and receiving diffusing signals. The mechanism we describe includes features such as programmable response thresholds and quorum quenching, and is capable of being triggered by proximity of a specific target cell. Nanoscale robots with swarm intelligence could carry out tasks that have been so far unachievable in diverse fields such as industry, manufacturing and medicine.

synthetic biology↗

bioRxiv2018

Digital therapeutics for distributed response to global pandemics

Despite advances in the development of drugs and vaccines, the spread of infectious diseases remains an imminent threat to our global health, in extreme cases potentially having detrimental consequences. At present our response to this threat is based on physically distributing therapeutic material, which utilizes the same transportation networks that support the spread of the infectious agent itself. Such competition is at risk of failure in the face of a rapidly spreading pathogen, especially given the inevitable delay from the initial outbreak to the development and execution of our response. Moreover, based on our existing transportation networks, we show that such physical distribution is intrinsically inefficient, leading to an uneven concentration of the therapeutic within a small fraction of destinations, while leaving the majority of the population deprived. This suggests that outrunning a virulent epidemic can only be achieved if we develop a mitigation strategy that bypasses the existing distribution networks of biological and chemical material. Here we propose such a response, utilizing digitizable therapeutics, which can be distributed as digital sequence files and synthesized on location, exposing an extremely efficient mitigation scheme that systematically outperforms physical distribution. Our proposed strategy, based for example on nucleic acid therapeutics, is plausibly the only viable mitigation plan, based on current technology, that can face a violently spreading pathogen. Complementing the current paradigm, which ranks drugs based on efficacy, our analysis demonstrates the importance of balancing efficacy with distributability, finding that in some cases the latter plays the dominant role in the overall mitigation efficiency.

bioinformatics↗

bioRxiv2018

Molecular anatomy and plasticity of the long noncoding RNA HOTAIR

Long noncoding RNA molecules (lncRNAs) are estimated to account for the majority of eukaryotic genomic transcripts, and have been associated with multiple diseases in humans. However, our understanding of their structure-function relationships is scarce, with structural evidence coming mostly from indirect biochemical approaches or computational predictions. Here we describe the hypothetical molecular anatomy of the lncRNA HOTAIR (HOx Transcript AntIsense RNA) inferred from direct, high-resolution visualization by atomic force microscopy (AFM) in nucleus-like conditions at 37 degrees. Our observations reveal that HOTAIR has a distinct anatomy with a high degree of plasticity. Fast AFM scanning enabled the quantification of this plasticity, and provided visual evidence of physical interactions with genomic DNA segments. Our report provides the first biologically-plausible hypothetical description of the anatomy and intrinsic properties of HOTAIR, and presents a framework for studying the structural biology of lncRNAs.

biophysics↗