This is a Pleckstrin Homology (PH) domain found on the N-terminal region of the histone chaperone Rtt106 in yeast. Rtt106 binds histone H3 acetylated at lysine 56 (H3K56ac) and facilitates nucleosome assembly during several molecular processes and this N-PH domain is shown to mediate histone binding [1].

1: Structural basis for recognition of H3K56-acetylated histone H3-H4 by the chaperone Rtt106. Su D, Hu Q, Li Q, Thompson JR, Cui G, Fazly A, Davies BA, Botuyan MV, Zhang Z, Mer G; Nature. 2012;483:104-107. PMID:22307274

2: Structural analysis of Rtt106p reveals a DNA binding role required for heterochromatin silencing. Liu Y, Huang H, Zhou BO, Wang SS, Hu Y, Li X, Liu J, Zang J, Niu L, Wu J, Zhou JQ, Teng M, Shi Y; J Biol Chem. 2010;285:4251-4262. PMID:20007951

3: Two surfaces on the histone chaperone Rtt106 mediate histone binding, replication, and silencing. Zunder RM, Antczak AJ, Berger JM, Rine J; Proc Natl Acad Sci U S A. 2012;109:E144-E153. PMID:22198837