title: NAP1 family histone chaperones are required for somatic homologous recombination in Arabidopsis.
abstract: Homologous recombination (HR) is essential for maintaining genome integrity and variability. To orchestrate HR in the context of chromatin is a challenge, both in terms of DNA accessibility and restoration of chromatin organization after DNA repair. Histone chaperones function in nucleosome assembly/disassembly and could play a role in HR. Here, we show that the NUCLEOSOME ASSEMBLY PROTEIN1 (NAP1) family histone chaperones are required for somatic HR in Arabidopsis thaliana. Depletion of either the NAP1 group or NAP1-RELATED PROTEIN (NRP) group proteins caused a reduction in HR in plants under normal growth conditions as well as under a wide range of genotoxic or abiotic stresses. This contrasts with the hyperrecombinogenic phenotype caused by the depletion of the CHROMATIN ASSEMBLY FACTOR-1 (CAF-1) histone chaperone. Furthermore, we show that the hyperrecombinogenic phenotype caused by CAF-1 depletion relies on NRP1 and NRP2, but the telomere shortening phenotype does not. Our analysis of DNA lesions, H3K56 acetylation, and expression of DNA repair genes argues for a role of NAP1 family histone chaperones in nucleosome disassembly/reassembly during HR. Our study highlights distinct functions for different families of histone chaperones in the maintenance of genome stability and establishes a crucial function for NAP1 family histone chaperones in somatic HR.
authors.affiliation: State Key Laboratory of Genetic Engineering, Department of Biochemistry, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, People's Republic of China.
authors.forename: Juan
authors.initials: J
authors.lastname: Gao
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhu
authors.forename: Wangbin
authors.initials: W
authors.lastname: Zhou
authors.forename: Jean
authors.initials: J
authors.lastname: Molinier
authors.forename: Aiwu
authors.initials: A
authors.lastname: Dong
authors.forename: Wen-Hui
authors.initials: WH
authors.lastname: Shen
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics*; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D004249:DNA Damage; D004260:DNA Repair / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter / Q000235:genetics; D056488:Histone Chaperones / Q000378:metabolism*; D059765:Homologous Recombination / Q000235:genetics*; D018832:Molecular Chaperones / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D013312:Stress, Physiological / Q000235:genetics; D059505:Telomere Homeostasis / Q000235:genetics
chemical_list: D000251:Adenosine Triphosphatases; D029681:Arabidopsis Proteins; D056488:Histone Chaperones; D018832:Molecular Chaperones; C517310:ABCI8 protein, Arabidopsis; C517311:NRP2 protein, Arabidopsis; C498859:NAP1 protein, Arabidopsis