Response regulators implicated in His-to-Asp phosphotransfer signaling in Arabidopsis.
The His to Asp phosphotransfer signal transduction mechanism involves three common signaling domains: the transmitter (or His-kinase), the receiver, and the histidine-containing phototransfer (HPt) domain. Typically, a sensor kinase has a His-kinase domain and a response regulator has a receiver domain containing a phosphoaccepting aspartate, whereas a histidine-containing phototransfer domain serves as a mediator of the histidine-to-aspartate phosphotransfer. This signal transduction mechanism was thought to be restricted to prokaryotes. However, many examples have been discovered in diverse eukaryotic species including higher plants. In Arabidopsis, three sensor kinases have been characterized, namely, ETR1, ERS, and CKI1, which were suggested to be involved in ethylene- and cytokinin-dependent signal transduction pathways, respectively. To date, no response regulator has been discovered in higher plants. We identify five distinct Arabidopsis response regulator genes, each encoding a protein containing a receiver-like domain. In vivo and in vitro evidence that ARRs can function as phosphoaccepting response regulators was obtained by employing the Escherichia coli His-Asp phosphotransfer signaling system.
Imamura
A
A
Laboratory of Molecular Microbiology, School of Agriculture, Nagoya University, Chikusa-ku, Nagoya 464, Japan.
Hanaki
N
N
Umeda
H
H
Nakamura
A
A
Suzuki
T
T
Ueguchi
C
C
Mizuno
T
T
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins; D001426:Bacterial Proteins; D004926:Escherichia coli / Q000378:metabolism; D017343:Genes, Plant; D005809:Genes, Regulator; D008565:Membrane Proteins / Q000737:chemistry; D000072236:Methyl-Accepting Chemotaxis Proteins; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics; D011494:Protein Kinases / Q000235:genetics; D011956:Receptors, Cell Surface / Q000235:genetics; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction
D029681:Arabidopsis Proteins; D001426:Bacterial Proteins; C095706:ERS protein, Arabidopsis; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins; D010940:Plant Proteins; D011956:Receptors, Cell Surface; C083750:ethylene receptors, plant; D011494:Protein Kinases; C101990:CKI1 protein, Arabidopsis