This domain is found at the C-terminus of the RAG2 protein. The structure of this domain has been shown bound to histone H3 trimethylated at lysine 4 (H3K4me3) [1].

1: RAG2 PHD finger couples histone H3 lysine 4 trimethylation with V(D)J recombination. Matthews AG, Kuo AJ, Ramon-Maiques S, Han S, Champagne KS, Ivanov D, Gallardo M, Carney D, Cheung P, Ciccone DN, Walter KL, Utz PJ, Shi Y, Kutateladze TG, Yang W, Gozani O, Oettinger MA; Nature. 2007;450:1106-1110. PMID:18033247