Oryza sativa ObgC1 Acts as a Key Regulator of DNA Replication and Ribosome Biogenesis in Chloroplast Nucleoids

Abstract Background The Spo0B-associated GTP-binding protein (Obg) GTPase, has diverse and important functions in bacteria, including morphological development, DNA replication ribosome maturation. Homologs of the Bacillus subtilis Obg have been also found chloroplast Oryza sativa , but their primary roles remain unknown. Results We clarify that OsObgC1 is a functional homolog AtObgC. mutant obgc1-d1 exhibited hypersensitivity to inhibitor hydroxyurea. Quantitative PCR results showed ratio nuclear mutants was higher than wild-type plants. After DAPI staining, abnormal nucleoid architectures. specific punctate staining pattern OsObgC1-GFP signal suggests this localizes nucleoids. Furthermore, loss-of-function mutation led severe suppression biosynthesis by affecting plastid rRNA processing. It demonstrated through profiling processing decreased obgc1-d mutants, which resulted impaired biogenesis. sucrose density gradient profiles revealed defective maturation mutants. Conclusion Our findings here indicate retains evolutionarily biological conserved prokaryotic Obg, acts as signaling hub regulates biogenesis