PTD2 is a peptide derived from the histone H4 sequence surrounding residue K44 (H4K44) that acts as an inhibitor of Wolf-Hirschhorn syndrome candidate 1 (WHSC1). WHSC1 (also known as NSD2 or MMSET) is a histone 3 lysine 36 (H3K36) specific methyltransferase that is responsible for mono- and dimethylation of lysine 36 on histone H3, and is frequently deleted in the genetic disorder Wolf-Hirschhorn syndrome, and has also been implicated as a driver in a variety of haematological and solid tumours. PTD2 inhibits WHSC1 in biochemical and biophysical assays with similar micromolar potencies, but demonstrates no enzymatic inhibition against a panel of other histone methyltransferases. PTD2 is a valuable tool for in vitro assay development and validation.
