Figure 2.

Interplay between Nuclear Organization and Dosage Compensation. (A) Schematic representation of the chromosome organization inside a male nucleus. rex sites direct the interaction of the X chromosome with the nuclear periphery, which in turn leads to pore interactions, promoting transcriptional upregulation. (B) Same as A in a hermaphrodite nucleus. DCC binding to rex sites and spreading on X chromatin impairs perinuclear localization and interaction with nuclear pore proteins, thereby impairing activation of X-linked transcripts and promoting chromosomal compaction. (C) Comparison between the previous and proposed models of Dosage Compensation in C. elegans. In the proposed model, the final transcriptional output of the X chromosome is a consequence of pore mediated activation in males and impairment of this activation by the DCC in hermaphrodites.