Was the evolution of plastid genetic machinery discontinuous?

The plastid nucleoid consists of plastid DNA and various, mostly uncharacterized, DNA-binding proteins. The plastid DNA undoubtedly originated from an ancestral cyanobacterial genome, but the origin of the nucleoid proteins appears complex. Initial biochemical analysis of these proteins, as well as comparative genome informatics, suggest that proteins of eukaryotic origin replaced most of the original prokaryotic proteins during the evolution of plastids in the lineage of green plants.