Eukaryotic histones package DNA to help it to fit in the nucleus, and they are known to be the most conserved proteins in nature.

HU-type proteins have been found in a variety of bacteria (including cyanobacteria) and archaea, and are also encoded in the chloroplast genome of some algae.

[4] The integration host factor (IHF), a dimer of closely related chains which is suggested to function in genetic recombination as well as in translational and transcriptional control[5] is found in Enterobacteria and viral proteins including the African swine fever virus protein A104R (or LMW5-AR).

An unstable SSB/DNA system would result in rapid disintegration of the SSB, which stalls DNA replication.

H-NS is about 15.6 kDa and assists in the regulation of bacterial transcription in bacteria by repressing and activating certain genes.

In E. coli, H-NS binds to a P1 promoter decreasing rRNA production during stationary and slow growth periods.

When H-NS is bound with RNA Polymerase to the promoter region, there are structural differences in the DNA that are accessible.

[13] Recent research has revealed that HU binds with high specificity to the mRNA of rpoS,[14] a transcript for the stress sigma factor of RNA polymerase, and stimulates translation of the protein.

Integration host factor, IHF, is not a nucleoid-associated protein only found in gram negative bacteria.

[15] It is a 20 kDa heterodimer, composed of α and β subunits that bind to the sequence 5' - WATCAANNNNTTR - 3' and bends the DNA approximately 160 degrees.

This directing of integration by IHF ensures that spacers are added chronologically, allowing better protection against the most recent viral infection.

Further studies are aiming to characterize the ways this nucleoid-organizing protein affects the motility of the cell through other regulatory pathways.