Histone H3 (1-25), amide is an N-terminal peptide fragment of histone H3. Histone H3 (1-25), amide can be used to identify the substrate for histone methyltransferases (HMTs). Histone H3 (1-25), amide, as a substrate for HMT G9a, shows more efficient than histone H3 (15-39) and full-length histone H3.