The myocyte enhancer factor-2 (MEF2) binding domain, predominantly found in the calcineurin-binding protein CABIN 1, adopts an amphipathic alpha-helical structure, which allows it to bind a hydrophobic groove on the MEF2S domain, forming a triple-helical interaction. Interaction of this domain with MEF2 causes repression of transcription [1].

1: Sequence-specific recruitment of transcriptional co-repressor Cabin1 by myocyte enhancer factor-2. Han A, Pan F, Stroud JC, Youn HD, Liu JO, Chen L; Nature. 2003;422:730-734. PMID:12700764