Fig. 9.

X chromosome decondensation and condensation during dosage compensation. A graphical cartoon illustrates the effects of MYS-1 and DCC on X chromosome structure in male and hermaphrodite C. elegans. In young embryos, the genome is uniformly compacted. The HAT MYS-1, which is a member of a putative worm Tip60-/NuA4-like complex, mediates decondensation of the X in males, while the DCC mediates condensation of the X in hermaphrodites. Additionally, MYS-1 activity is required for proper DCC localization, and therefore function, in hermaphrodites. Note that DCC-mediated compaction in hermaphrodites is accompanied by a twofold repression of X-linked gene expression, but MYS-1-mediated gene expression changes on the male X are much less significant