A. Akhtar et Pb. Becker, Activation of transcription through histone H4 acetylation by MOF, an acetyltransferase essential for dosage compensation in Drosophila, MOL CELL, 5(2), 2000, pp. 367-375
Dosage compensation in Drosophila involves a P-fold increase in transcripti
on from the single male X relative to the two female X chromosomes. Regulat
ion at the level of the chromosome involves alterations in chromatin organi
zation: male X chromosomes appear decondensed and are marked by acetylation
of histone H4 at lysine 16. We demonstrate that MOF, a protein required fo
r dosage compensation with significant sequence similarity to the MYST fami
ly of acetyltransferases, is a histone acetyltransferase that acetylates ch
romatin specifically at histone H4 lysine 16. This acetylation relieves chr
omatin-mediated repression of transcription in vitro and in vivo if MOF is
targeted to a promoter by fusion to a DNA-binding domain. Acetylation of ch
romatin by MOF, therefore, appears to be causally involved in transcription
al activation during dosage compensation.