AC   MF_01837;
DC   Protein; auto
TR   HAMAP; MF_01837; -; 1; level=0
XX
Names: Kinase_SasA
XX
ID   SASA
DE   RecName: Full=Adaptive-response sensory-kinase SasA;
DE            EC=2.7.13.3;
DE   AltName: Full=Sensor histidine kinase SasA;
GN   Name=sasA;
XX
CC   -!- FUNCTION: Member of the two-component regulatory system SasA/RpaA
CC       involved in genome-wide circadian gene expression. One of several clock
CC       output pathways. Participates in the Kai clock protein complex, the
CC       main circadian regulator in cyanobacteria, via its interaction with
CC       KaiC. KaiC enhances the autophosphorylation activity of SasA, which
CC       then transfers its phosphate group to RpaA to activate it. In addition
CC       to its output function, recruits fold-shifted KaiB (KaiB(fs)) to KaiC
CC       to cooperatively form the KaiB(6):KaiC(6) complex (independent of SasA
CC       kinase activity). Required for robustness of the circadian rhythm of
CC       gene expression and is involved in clock output, also required for
CC       adaptation to light/dark cycles.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=ATP + protein L-histidine = ADP + protein N-phospho-L-
CC         histidine.; EC=2.7.13.3;
case not <OC:Prochlorococcus>
CC   -!- SUBUNIT: Homooligomerizes. Interacts with KaiC. Participates in the
CC       KaiABC clock complex, whose core is composed of a KaiC homohexamer, 6
CC       KaiB and up to 6 KaiA dimers. SasA and KaiB(fs) compete to bind to
CC       KaiC.
end case
case <OC:Prochlorococcus>
CC   -!- SUBUNIT: Homooligomerizes. Interacts with KaiC. Participates in the
CC       KaiBC complex, whose core is composed of a KaiC homohexamer and 6 KaiB.
end case
CC   -!- DOMAIN: The N-terminus interacts with KaiC, while the C-terminal
CC       histidine kinase domain autophosphorylates and is probably responsible
CC       for self-oligomerization. The N-terminal domain stimulates the C-
CC       terminus to autophosphorylate.
XX
DR   Pfam; PF02518; HATPase_c; 1; trigger=no
DR   Pfam; PF00512; HisKA; 1; trigger=no
DR   Pfam; PF07689; KaiB; 1; trigger=no
DR   PRINTS; PR00344; BCTRLSENSOR; 1; trigger=no
DR   PROSITE; PS50109; HIS_KIN; 1; trigger=yes
XX
KW   ATP-binding
KW   Nucleotide-binding
KW   Biological rhythms
KW   Kinase
KW   Phosphoprotein
KW   Transferase
KW   Two-component regulatory system
XX
GO   GO:0007623; P:circadian rhythm
GO   GO:0004673; F:protein histidine kinase activity
XX
FT   From: SASA_SYNE7 (Q06904)
FT   MOD_RES         161
FT                   /note="Phosphohistidine; by autocatalysis"
FT   Condition: H
XX
Size: 370-401;
Related: None;
Template: Q06904;
Scope:
 Bacteria; Cyanobacteriota
Fusion:
 Nter: None
 Cter: None
Duplicate: None
Plasmid: None
Comments: None
XX
# Revision 1.18 2023/02/17
//