High impact information on Aef1

• The aef1 site represses ectopic transcription in ovaries and dsxA antirepresses this activity in fat bodies [1].
• Here, we show that the AEF-1-binding site in the AAE and in two other Drosophila fat body enhancers overlaps a sequence recognized by the mammalian transcription factor CCAAT/enhancer-binding protein (C/EBP) [2].
• Here, we provide evidence that this Adh promoter switch is regulated by a zinc finger repressor protein (AEF-1) that is expressed predominantly in adult flies and targets the initiator region of the proximal promoter [3].
• The AEF-1 protein contains four zinc fingers and an alanine-rich sequence [4].
• Thus, the AEF-1 binding site is a negative regulatory element within the AAE [4].

Physical interactions of Aef1

• Base substitutions in the AEF-1 binding site that disrupt AEF-1 binding in vitro result in a significant increase in the level of Adh expression in vivo [4].

Other interactions of Aef1

• We propose that AEF-1 plays a critical role in Adh promoter switching by blocking interactions between a component of the general transcription machinery and the initiator region of the proximal promoter [3].
• A UAS site substitution approach to the in vivo dissection of promoters: interplay between the GATAb activator and the AEF-1 repressor at a Drosophila ecdysone response unit [5].

References