CTCF‐mediated reduction of vigilin binding affects the binding of HP1α to the satellite 2 locus

Abstract

Edited by Ned ManteiKeywords: Vigilin CCCTC-binding factor HP1a Satellite 2 a b s t r a c t CCCTC-binding factor (CTCF) has been implicated in numerous aspects of chromosome biology, and vigilin, a multi-KH-domain protein, participates in heterochromatin formation and chromosome segregation. We previously showed that CTCF interacts with vigilin. Here, we show that human vigilin, but not CTCF, colocalizes with HP1a on heterochromatic satellite 2 and b-satellite repeats. CTCF up-regulates the transcription of satellite 2, while vigilin down-regulates it. Vigilin depletion or CTCF overexpression reduces the binding of HP1a on the satellite 2 locus. Furthermore, overexpression of CTCF resists the loading of vigilin onto the satellite 2 locus. Thus CTCF may regulate vigilin behavior and thus indirectly influence the binding of HP1a to the satellite 2 locus.