Fig. 2.

Overview of high-order chromosomal structure dynamics during mammalian spermatogenesis. The gray arrow in the middle marks the hallmark events during spermatogenesis. The colored bands at the bottom indicate the intensity of 3D chromatin structural features. TAD and compartment strengths are weakened or even disappeared during meiosis I and recovered right after the entry of meiosis II. (It should be noted that TAD insulator score color bar does not apply to humans, which, unlike those in mice, human sperm cells are reported not to have TADs). Long range loop arrays (>500 kb) are gradually formed during meiosis I, with the slope of log-log scale P (s) curve rising from −1.2 to −0.6.