Dear Editor,rnMammalian cells encode five members of the nucleosome assembly protein 1 (NAP1) family of proteins including nucleosome assembly protein 1-like 1 (NAP1L1),NAP1L2,NAP1L3,NAP1L4 and NAP1L5 (Attia et al.2011).NAP1L1 is ubiquitously expressed and has been implicated in several processes of transcription and DNA replication,such as the nucleosome assembly,nucleosome sliding,transcriptional activation through chromatin remodeling,and nucleocytoplasmic shuttling of histones (Lee et al.2017;Moshkin et al.2009;Zlatanova et al.