The Hfq protein – a novel view on the well-known riboregulator

The Hfq protein is one of the most important regulatory factors acting at the RNA level. This protein was first discovered as a host factor necessary for Qβ bacteriophage development. Following the discovery, the Hfq role in bacteriophage development was not investigated in depth. In subsequent years, however, many studies revealed various riboregulatory functions of this protein, mainly focused on facilitating sRNA and mRNA pairing, regulating both the degradation and stability of many transcripts. The Hfq protein has the ability to bind to nucleic acids – it binds more efficiently to RNA, but can also attach to DNA. It has been also proved that Hfq is involved in the nucleoid organization. These observations open room for discussion on the potential role of Hfq in the regulation of DNA replication. Since Hfq protein affects many cellular processes, the deletion of the gene encoding this protein has a pleiotropic effect on the cell.

1. Introduction. 2. The history of the Hfq protein discovery and its evolutionary context. 3. Structure of the Hfq protein and its molecular function. 4. Characteristics of cells devoid of the Hfq protein. 5. Hfq interactions with the DNA. 6. Summary