question: Which proteins act as histone-like molecules in prokaryotes?
answer: Prokaryotic histone-like proteins (Hlps) or nucleoid-associated proteins (NAPs) are abundant proteins found in bacterial and plastid nucleoids. HU protein is a small, basic, heat-stable DNA-binding protein that is well-conserved in prokaryotes and is associated with the bacterial nucleoid. HU is well conserved in all prokaryotes but surprisingly, it is also homologous to another E. coli DNA-binding protein, IHF. In prokaryotes, IHF and HU are key architectural proteins present at high concentrations. Histone-like Nucleoid Structuring (H-NS) protein can facilitate correct recognition of a promoter by RNA polymerase in AT-rich gene regulatory regions