Yeast AFF9 is a YEATS domain protein that binds to modified histones, with a preference for crotonyllysine over acetyllysine. Histone crotonylation upregulates gene expression in an AF9-dependent manner. Sub-family also includes eleven-nineteen-leukemia protein ENL, which binds histones H3 and H1. DNA regulation by chromatin through histone post-translational modification and other mechanisms involves complexes with write, eraser and reader functions. YEATS domains act as readers of the chromatin state and stimulates transcriptional activity through preferential interactions with crotonylated lysines on histones. The YEATS family is named for several family members: 'YNK7', 'ENL', 'AF-9', and 'TFIIF small subunit', and also contains the GAS41 protein.
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