Fig 9. Schematic representation of possible mechanism of gene regulation by Leishmania donovani HAT2.

Upper panel: HAT2-mediated H4K10 acetylation of dSSRs is constitutively maintained, helps activate global transcription of polycistronic gene clusters that are then processed to individual gene transcripts prior to translation. Middle panel: In addition to dSSR activation, HAT2-mediated H4K10 acetylation activates certain gene-specific promoters in a cell cycle-dependent manner, resulting in dramatic upregulation of the gene’s expression. Lower panel: In HAT2-depleted cells H4K10 acetylation decreases by ~ 50% at both, dSSRs and at cell cycle-distinctive promoters. However, transcription initiation from dSSRs remains largely unaffected, while initiation at cell cycle-distinctive promoters is proportionately lowered, reducing gene expression.