Nucleosome assembly protein 1-like 5

NAP1L5 (nucleosome assembly protein 1-like 5) is a 182-amino-acid protein involved in nucleosome assembly and chromatin organization (UniProt: Q96NT1). It belongs to the NAP1 family of histone chaperones, which facilitate the deposition and removal of nucleosomes during DNA replication, transcription, and repair.

While UniProt does not document specific tissue localization or disease associations for NAP1L5, the protein functions broadly in chromatin remodeling pathways essential to neuronal function. Nucleosome assembly factors are critical for maintaining proper gene expression patterns and genomic stability in the brain.

NAP1L5 is down-regulated in Alzheimer's disease brain tissue compared to age-matched controls (Chaparral AD proteomics). The mean log2 fold-change is −0.4941, representing a modest but consistent reduction across post-mortem AD brain samples analyzed via mass spectrometry (TMT-labeled proteomics across four subcellular fractions). This down-regulation may reflect impaired chromatin remodeling or altered histone dynamics in AD pathology.