FIGURE 3.

A) We find that XACT RNA produces a substantial accumulation (almost the same size as XIST RNA), but “paints” only a portion of the Xa territory. The Xa territory is very large and distended in pluripotent human stem cells (WIBR2 hESCs), and the XACT RNA signal would be much larger than the XIST RNA signal (which is coating a compacted Xi territory) if it painted the whole Xa territory. B) Even on a large autosome (Chromosome 4) carrying an XIST transgene, we consistently find that XIST RNA paints the vast majority of the chromosome territory. The green XIST RNA channel is shown alone in the insert. C) Cot-1 ecRNA signal consistently forms a tightly cis-limited RNA territory, with little to no “drift” of RNA away from the parent DNA territory (shown for a single human chromosome in a mouse/human hybrid cell). D) An illustration of the amount of interphase X-chromosome territory typically “painted” by XIST RNA (green) and XACT RNA (yellow) in a pluripotent cell (as seen by us and in published images) [28]. E) An illustration of the amount of interphase chromosome-15 territory typically “painted” by ASAR5 RNA (as seen in published images) [30]. F) An illustration of the amount of a human interphase chromosome territory typically “painted” by Cot-1 ecRNA in mouse/human hybrid cells (as seen in our published images) [39].