Molecular propulsion: chemical sensing and chemotaxis of DNA driven by RNA polymerase.
Living cells sense extracellular signals and direct their movements in response to stimuli in environment. Such autonomous movement allows these machines to sample chemical change over a distance, leading to chemotaxis. Synthetic catalytic rods have been reported to chemotax toward hydrogen peroxide fuel. Nevertheless individualized autonomous control of movement of a population of biomolecules under physiological conditions has not been demonstrated. Here we show the first experimental evidence that a molecular complex consisting of a DNA template and associating RNA polymerases (RNAPs) displays chemokinetic motion driven by transcription substrates nucleoside triphosphates (NTPs). Furthermore this molecular complex exhibits a biased migration into a concentration gradient of NTPs, resembling chemotaxis. We describe this behavior as "Molecular Propulsion", in which RNAP transcriptional actions deform DNA template conformation engendering measurable enhancement of motility. Our results provide new opportunities for designing and directing nanomachines by imposing external triggers within an experimental system.
Yu
Hua
H
Department of Chemistry, University of Wisconsin, 425 Henry Mall, Madison, Wisconsin 53706, USA.
Jo
Kyubong
K
Kounovsky
Kristy L
KL
de Pablo
Juan J
JJ
Schwartz
David C
DC
D004247:DNA / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism*; D004058:Diffusion; D036681:Fluorescence Recovery After Photobleaching; D005456:Fluorescent Dyes / Q000737:chemistry; D009038:Motion; D036103:Nanotechnology; D009690:Nucleic Acid Conformation; D009711:Nucleotides / Q000737:chemistry / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
D005456:Fluorescent Dyes; D009711:Nucleotides; D014764:Viral Proteins; D004247:DNA; C062210:bacteriophage T7 RNA polymerase; D012321:DNA-Directed RNA Polymerases