Loss of Atg7 causes chaotic nucleosome assembly of mouse bone marrow CD11bLy6G myeloid cells.

Atg7, a critical component of autophagy machinery, is essential for counteracting hematopoietic aging. However, the non-autophagic role of Atg7 on hematopoietic cells remains fundamentally unclear. In this study, we found that loss of Atg7, but not Atg5, another autophagy-essential gene, in the hematopoietic system reduces CD11b myeloid cellularity including CD11bLy6G and CD11bLy6G populations in mouse bone marrow. Surprisingly, Atg7 deletion causes abnormally accumulated histone H3.1 to be overwhelmingly trapped in the cytoplasm in the CD11bLy6G, but not the CD11bLy6G compartment. RNA profiling revealed extensively chaotic expression of the genes required in nucleosome assembly. Functional assays further indicated upregulated aging markers in the CD11bLy6G population. Therefore, our study suggests that Atg7 is essential for maintaining proper nucleosome assembly and limiting aging in the bone marrow CD11bLy6G population.