DNA loop organization in dorsal root ganglion neurons: effects of peripheral inflammation

The loop domain organization of chromatin plays an important role in transcription regulation and is known to be dependent on cell functional states. Aim. To investigate possible DNA loop reorganization in dorsal ganglion neurons upon inflammatory pain. Methods. We used single cell gel electrophoresis (the comet assay) to analyze the kinetics of the DNA loop migration from nucleoids obtained from lysed neurons. Results. Independently of inflammation, the neurons are characterized by relatively low amount of DNA in the comet tails due to a low content of DNA in the loops, which may be resolved by the comet assay (up to ~400 kb). Upon inflammation the contour length of the loops essentially decreases, in parallel with a respective increase of DNA in relatively short (up to ~100 kb) loops. Conclusions. A reorganization of the DNA loops upon inflammation could be suggested to be accompanied by rather significant changes in transcription regulation.