FIG. 2.

Rph1 requires the JmjN/JmjC domains but not the ZF domain for demethylase activity. (A) Schematic representation of Rph1 indicating the three curated domains within Rph1. The JmjN, JmjC, and ZF domains were individually deleted or mutated to examine the domain requirements and to map the smallest catalytically active fragment of Rph1. WT, wild type; aa, amino acids. (B) The mutant Rph1 proteins displayed in A were used in a histone demethylase assay containing H3K36-labeled substrate, and histone demethylase activity was monitored by formaldehyde release. The JmjN and JmjC domains of Rph1 are sufficient for H3K36 demethylation. CPM, counts per minute.