Fig. 1: Centromeres are anchored and scattered at the nuclear periphery in germ cells.
From: Global reorganization of genome architecture at the transition to gametogenesis
a, Top: schematic overview of nuclear architecture and heterochromatin changes during mouse PGC development. Bottom: timeline of the generation of PGCLCs and similarities to the development in vivo. b, Representative transmission electron microscopy images for somatic cells and germ cells at E13.5 (n = 2 embryos). c, Nuclear distribution of CENPA using IF staining in embryo (E9.5) or gonadal (E11.5–E13.5) sections (n = 3 biological replicates). OCT4, germ cell marker. Yellow arrowheads indicate PGCs. The square marks the cell selected for the zoomed-in view. DNA was stained with DAPI (blue). Scale bars, 10 µm (main images), 1 µm (zoomed-in view). d, Measurement of the shortest distance of each CENPA focus to the nuclear periphery. The mean value of each nucleus was calculated. n represents the number of cells analyzed. P values were calculated by two-tailed Mann–Whitney U-test (n = 3 embryos derived from independent litters and analyzed with 3 independent experiments). Box plots were plotted using Tukey’s method. The median and the first and third quartiles are indicated. The whiskers represent the furthest value within 1.5× the IQR. e, Percentage of cells with periphery (average distance of centromere to the nuclear periphery < 1 µm) and nonperiphery centromere association pattern. f, Minor satellite DNA-FISH on gonadal sections. DNA was stained with DAPI (blue). Data are representative of two independent experiments. Scale bar, 10 µm. g, Representative 3D reconstruction image. The total number of CENPA foci was calculated for each nucleus. The mean value is shown. Each dot represents the number derived from an individual cell (mean ± s.d.). The P values were calculated using a two-tailed Mann–Whitney U-test. h, Western blot analysis of CENPA. A total of 10,000 GFP-positive (PGC) and GFP-negative (Soma) cells were sorted using FACS from gonads of the Oct4–GFP mice (GOF 18ΔPE–EGFP) (n = 2 embryos derived from independent litters and analyzed with 2 independent experiments). *P < 0.05, ***P < 0.001.
