Disruption of<i>NAP1</i>genes in<i>Arabidopsis thaliana</i>suppresses the<i>fas1</i>mutant phenotype, enhances genome stability and changes chromatin compaction

SUMMARY Histone chaperones mediate the assembly and disassembly of nucleosomes participate in essentially all DNA‐dependent cellular processes. In Arabidopsis thaliana , loss‐of‐function FAS1 or FAS2 subunits H3‐H4 histone chaperone complex CHROMATIN ASSEMBLY FACTOR 1 (CAF‐1) has a dramatic effect on plant morphology, growth overall fitness. CAF‐1 dysfunction can lead to altered chromatin compaction, systematic loss repetitive elements increased DNA damage, clearly demonstrating its severity. How composition is maintained without functional remains elusive. Here we show that disruption H2A‐H2B NUCLEOSOME PROTEIN (NAP1) suppresses phenotype. The quadruple mutant fas1 nap1;1 nap1;2 nap1;3 shows wild‐type growth, decreased sensitivity genotoxic stress suppression telomere 45S rDNA loss. Chromatin plants less accessible micrococcal nuclease nuclear H3.1 H3.3 pools change compared . Consistently, association between NAP1 H3 occurs cytoplasm nucleus vivo protoplasts. Altogether proteins play an essential role repair which coupled nucleosome through modulation levels nucleus.