Heterozygosity for the proteasomal Psmc1 ATPase is insufficient to cause neuropathology in mouse brain, but causes cell cycle defects in mouse embryonic fibroblasts

► Proteasomal Psmc1 ATPase heterozygosity does not cause neuropathology in mouse brain. ► Age-related intraneuronal K48-specific polyubiquitin granular staining in mouse brain. ► Proteasomal Psmc1 ATPase heterozygosity leads to cell cycle defects in MEFs.