Journal: bioRxiv
Article Title: Transcription swells chromosomes in vitro
doi: 10.1101/2024.09.25.614905
Figure Lengend Snippet: a) A DNA molecule of the lambda bacteriophage was labeled on specific sites with fluorophores (dC-Cy5, purple star) for imaging and with biotins for surface immobilization in an open microfluidic chip. The surface-immobilized lambda DNA molecule (yellow dashed line) was stretched by flow (yellow solid-line circle). b) A representative fluorescence time-lapse montage shows a DNA molecule before, during, and after a moderate flow pulse. We tracked the position of the fluorescent dye to measure DNA extension, as shown for three different displacement examples. c) The DNA extension by flow was measured after incubating the DNA molecules for 30 minutes in cell-free expression systems with active transcription (Tx), without Tx by adding 500 nM rifampicin, and in phosphate-buffered saline (PBS) solution as a protein-free reference. The data were combined for Tx(ON), Tx(OFF), and buffer from n=3,2,3 independent experiments with mean values as yellow bars and individual molecules as circles.
Article Snippet: The purified lambda DNA was further nick-translated with 25 µM dG, 25 µM dA, 25 µM dT, 15 µM dC, 10 µM dC-Cy5 (Jena Biosciences) and cleaned as described above.
Techniques: Labeling, Imaging, Lambda DNA Preparation, Fluorescence, Expressing, Saline