Cyanobacterial response regulator PatA contains a conserved N-terminal domain (PATAN) with an alpha-helical insertion.
The cyanobacterium Anabaena (Nostoc) PCC 7120 responds to starvation for nitrogen compounds by differentiating approximately every 10th cell in the filament into nitrogen-fixing cells called heterocysts. Heterocyst formation is subject to complex regulation, which involves an unusual response regulator PatA that contains a CheY-like phosphoacceptor (receiver, REC) domain at its C-terminus. PatA-like response regulators are widespread in cyanobacteria; one of them regulates phototaxis in Synechocystis PCC 6803. Sequence analysis of PatA revealed, in addition to the REC domain, a previously undetected, conserved domain, which we named PATAN (after PatA N-terminus), and a potential helix-turn-helix (HTH) domain. PATAN domains are encoded in a variety of environmental bacteria and archaea, often in several copies per genome, and are typically associated with REC, Roadblock and other signal transduction domains, or with DNA-binding HTH domains. Many PATAN domains contain insertions of a small additional domain, termed alpha-clip, which is predicted to form a four-helix bundle. PATAN domains appear to participate in protein-protein interactions that regulate gliding motility and processes of cell development and differentiation in cyanobacteria and some proteobacteria, such as Myxococcus xanthus and Geobacter sulfurreducens.
National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
Kira S
KS
Makarova
Eugene V
EV
Koonin
Robert
R
Haselkorn
Michael Y
MY
Galperin
D000595:Amino Acid Sequence; D017033:Anabaena / Q000378:metabolism; D018407:Bacterial Physiological Phenomena; D001426:Bacterial Proteins / Q000737:chemistry* / Q000502:physiology*; D002454:Cell Differentiation; D002465:Cell Movement; D019295:Computational Biology / Q000379:methods; D017124:Conserved Sequence; D019077:Helix-Turn-Helix Motifs; D008969:Molecular Sequence Data; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid
D001426:Bacterial Proteins; C075180:PatA protein, Anabaena