Nuclear Pore Proteins Nup153 and Megator Define Transcriptionally Active Regions in the Drosophila Genome (original) (raw)
Figure 4
Nup153 and Mtor define NARs both at the periphery and the interior of the nucleus.
(A) Representative images of single confocal sections of nuclei containing the FISH signal (red) over DAPI (blue) and immunostained lamin (green). Target genomic regions include a lamin-bound gene (L105), NAR (T4, T15, T7, T11, T9, T13) and non-NAR loci (N1, N2). Probability density plots show the distribution of distance measurements between the FISH signal and the closest point on the nuclear boundary. Simulated nuclei show the ideal distributions for FISH targets located at the (B) periphery and (C) interior. Distances range from 0 at the boundary and 1.0 at the centroid of the nucleus. The grey background represents the theoretical 30% limit for a peripherally localised FISH signal. Observed distributions of in vivo controls for (D) peripherally localised L105 and (E) non-peripherally localised N2; the broad spread compared with simulations indicate that the loci display dynamic behaviour in their positioning within the nucleus. (F, G) Predominantly peripheral loci (T4, T15) have distributions that are similar to L105 (shown in yellow), whereas (H, I) predominantly non-peripheral loci (N1, T11) have very different distributions. Aggregate distributions for all NAR targets on (J) the male X chromosome and (L) autosomes, and all non-NAR targets on (K) the male X and (M) autosomes. Targets on the X chromosome are peripherally localised compared with autosomal ones.