UniProt functional annotation for P19456



	UniProt functional annotation for P19456

UniProt code: P19456.

Organism: Arabidopsis thaliana (Mouse-ear cress).

Taxonomy: Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta; Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae; rosids; malvids; Brassicales; Brassicaceae; Camelineae; Arabidopsis.

Function: The plasma membrane H(+) ATPase of plants and fungi generates a proton gradient that drives the active transport of nutrients by H(+)-symport (PubMed:10748244, PubMed:12920605, PubMed:27013734). The resulting external acidification and/or internal alkinization may mediate growth responses (PubMed:10748244, PubMed:12920605). Involved in maintaining the membrane potential and delta-pH, together forming the plasma membrane protonmotive force (PMF) required for root and hypocotyl elongation and root tropism (PubMed:22214817, PubMed:24492258). Important for root growth and development during different nitrogen regimes (PubMed:25382626). Forms a functional cation-translocating unit with CNGC17 that is activated by PSKR1/BAK1 and possibly other BAK1/RLK complexes (PubMed:26071421). {ECO:0000269|PubMed:12920605, ECO:0000269|PubMed:22214817, ECO:0000269|PubMed:24492258, ECO:0000269|PubMed:25382626, ECO:0000269|PubMed:26071421, ECO:0000269|PubMed:27013734, ECO:0000305|PubMed:10748244}.

Catalytic activity: Reaction=ATP + H(+)(in) + H2O = ADP + 2 H(+)(out) + phosphate; Xref=Rhea:RHEA:20852, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:30616, ChEBI:CHEBI:43474, ChEBI:CHEBI:456216; EC=7.1.2.1; Evidence={ECO:0000305};

Activity regulation: Regulated by an auto-inhibitory C-terminal domain that can be displaced by phosphorylation of Thr-947 and the subsequent binding of 14-3-3 proteins (PubMed:10353834). Negatively regulated by PKS5 (PubMed:17483306). PKS5 phosphorylates Ser-931, inhibiting interaction with the activating 14-3-3 protein (PubMed:17483306). Positively regulated by PSY1R (PubMed:25267325). PSY1R phosphorylates Thr-881, situated in the auto-inhibitory region I of the C-terminal domain, causing pump activation (PubMed:25267325). Negatively regulated by the secreted peptide RALF (PubMed:24458638). After specific binding to FERONIA, RALF causes phosphorylation at Ser-899, mediating the inhibition of proton transport (PubMed:24458638). Activated by lysophospholipids, without the involvement of phosphorylation of Thr- 947 (PubMed:25971968). This activation is critically dependent on the single autoinhibitory residue Leu-919 (PubMed:25971968). {ECO:0000269|PubMed:10353834, ECO:0000269|PubMed:10593986, ECO:0000269|PubMed:17483306, ECO:0000269|PubMed:24458638, ECO:0000269|PubMed:25267325, ECO:0000269|PubMed:25971968}.

Biophysicochemical properties: Kinetic parameters: KM=1.2 mM for ATP {ECO:0000269|PubMed:25971968}; Vmax=0.87 umol/min/mg enzyme {ECO:0000269|PubMed:25971968};

Subunit: Binds to 14-3-3 proteins (PubMed:10593986). The binding is induced by phosphorylation of Thr-947 and it activates the H(+)-ATPase (PubMed:10593986). Interacts (via the R-domain) with PSY1R (via C- terminus) (PubMed:25267325). Part of a functional complex containing PSKR1, BAK1, CNGC17, and AHA (PubMed:26071421). Interacts with CNGC17 and PSKR1 (PubMed:26071421). {ECO:0000269|PubMed:10593986, ECO:0000269|PubMed:25267325, ECO:0000269|PubMed:26071421}.

Subcellular location: Cell membrane {ECO:0000269|PubMed:10995773, ECO:0000269|PubMed:25267325, ECO:0000269|PubMed:26071421, ECO:0000305|PubMed:15308754}; Multi-pass membrane protein {ECO:0000255}.

Tissue specificity: Higher levels in roots than in shoots (PubMed:2143186). Expressed in epidermal and root cortex cells, in phloem, xylem and root hairs (PubMed:17483306). Detected in cotyledons, hypocotyls, roots and root hairs (PubMed:25267325). {ECO:0000269|PubMed:17483306, ECO:0000269|PubMed:2143186, ECO:0000269|PubMed:25267325}.

Developmental stage: Expressed on the surface of developing seeds and up to the early globular stage of embryo development. {ECO:0000269|PubMed:20348108}.

Induction: Up-regulated by low nitrate conditions. {ECO:0000269|PubMed:25382626}.

Domain: The C-terminus contains a R-domain composed of 2 autoinhibitory regions (863-885 and 904-919). {ECO:0000269|PubMed:10353834}.

Ptm: Phosphorylation at Thr-881 by PSY1R (PubMed:17651370, PubMed:25267325). This phosphorylation activates proton pumping (PubMed:25267325). Decreased phosphorylation in response to flg22 elicitation (PubMed:17651370). {ECO:0000269|PubMed:17651370, ECO:0000269|PubMed:25267325}.

Ptm: Phosphorylation at Ser-899 is specifically induced by RALF1, thus leading to the inhibition of proton transport (PubMed:24458638). Increased phosphorylation in response to flg22 elicitation (PubMed:17651370). {ECO:0000269|PubMed:17651370, ECO:0000269|PubMed:24458638}.

Ptm: Phosphorylation of Thr-947 induces the binding to 14-3-3 proteins, but phosphorylation of Ser-931 interfers with this binding no matter whether Thr-947 is phosphorylated or not (PubMed:10593986, PubMed:17483306). Decreased phosphorylation in response to flg22 elicitation (PubMed:17651370). {ECO:0000269|PubMed:10593986, ECO:0000269|PubMed:17483306, ECO:0000269|PubMed:17651370}.

Ptm: Abscisic acid induces dephosphorylation of AHA2 in etiolated seedlings, suppressing ATP hydrolysis and hypocotyl elongation. {ECO:0000269|PubMed:24492258}.

Disruption phenotype: No visible phenotype under normal growth conditions, due to the redudancy with AHA1. Aha1 and aha2 double mutants are embryo lethal. {ECO:0000269|PubMed:20348108}.

Miscellaneous: The catalytic mechanism involves at least four different enzyme conformational states named E1, E1P, E2P, and E2, with the E1P- E2P transition accompanying the transfer of ion across the membrane. E1P and E2P are phosphorylated intermediates. {ECO:0000305|PubMed:10748244}.

Similarity: Belongs to the cation transport ATPase (P-type) (TC 3.A.3) family. Type IIIA subfamily. {ECO:0000305}.

Annotations taken from UniProtKB at the EBI.


Organism:		Arabidopsis thaliana (Mouse-ear cress).
Taxonomy:		Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta; Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae; rosids; malvids; Brassicales; Brassicaceae; Camelineae; Arabidopsis.



Function:		The plasma membrane H(+) ATPase of plants and fungi generates a proton gradient that drives the active transport of nutrients by H(+)-symport (PubMed:10748244, PubMed:12920605, PubMed:27013734). The resulting external acidification and/or internal alkinization may mediate growth responses (PubMed:10748244, PubMed:12920605). Involved in maintaining the membrane potential and delta-pH, together forming the plasma membrane protonmotive force (PMF) required for root and hypocotyl elongation and root tropism (PubMed:22214817, PubMed:24492258). Important for root growth and development during different nitrogen regimes (PubMed:25382626). Forms a functional cation-translocating unit with CNGC17 that is activated by PSKR1/BAK1 and possibly other BAK1/RLK complexes (PubMed:26071421). {ECO:0000269\|PubMed:12920605, ECO:0000269\|PubMed:22214817, ECO:0000269\|PubMed:24492258, ECO:0000269\|PubMed:25382626, ECO:0000269\|PubMed:26071421, ECO:0000269\|PubMed:27013734, ECO:0000305\|PubMed:10748244}.


Catalytic activity:		Reaction=ATP + H(+)(in) + H2O = ADP + 2 H(+)(out) + phosphate; Xref=Rhea:RHEA:20852, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:30616, ChEBI:CHEBI:43474, ChEBI:CHEBI:456216; EC=7.1.2.1; Evidence={ECO:0000305};
Activity regulation:		Regulated by an auto-inhibitory C-terminal domain that can be displaced by phosphorylation of Thr-947 and the subsequent binding of 14-3-3 proteins (PubMed:10353834). Negatively regulated by PKS5 (PubMed:17483306). PKS5 phosphorylates Ser-931, inhibiting interaction with the activating 14-3-3 protein (PubMed:17483306). Positively regulated by PSY1R (PubMed:25267325). PSY1R phosphorylates Thr-881, situated in the auto-inhibitory region I of the C-terminal domain, causing pump activation (PubMed:25267325). Negatively regulated by the secreted peptide RALF (PubMed:24458638). After specific binding to FERONIA, RALF causes phosphorylation at Ser-899, mediating the inhibition of proton transport (PubMed:24458638). Activated by lysophospholipids, without the involvement of phosphorylation of Thr- 947 (PubMed:25971968). This activation is critically dependent on the single autoinhibitory residue Leu-919 (PubMed:25971968). {ECO:0000269\|PubMed:10353834, ECO:0000269\|PubMed:10593986, ECO:0000269\|PubMed:17483306, ECO:0000269\|PubMed:24458638, ECO:0000269\|PubMed:25267325, ECO:0000269\|PubMed:25971968}.
Biophysicochemical properties:		Kinetic parameters: KM=1.2 mM for ATP {ECO:0000269\|PubMed:25971968}; Vmax=0.87 umol/min/mg enzyme {ECO:0000269\|PubMed:25971968};
Subunit:		Binds to 14-3-3 proteins (PubMed:10593986). The binding is induced by phosphorylation of Thr-947 and it activates the H(+)-ATPase (PubMed:10593986). Interacts (via the R-domain) with PSY1R (via C- terminus) (PubMed:25267325). Part of a functional complex containing PSKR1, BAK1, CNGC17, and AHA (PubMed:26071421). Interacts with CNGC17 and PSKR1 (PubMed:26071421). {ECO:0000269\|PubMed:10593986, ECO:0000269\|PubMed:25267325, ECO:0000269\|PubMed:26071421}.
Subcellular location:		Cell membrane {ECO:0000269\|PubMed:10995773, ECO:0000269\|PubMed:25267325, ECO:0000269\|PubMed:26071421, ECO:0000305\|PubMed:15308754}; Multi-pass membrane protein {ECO:0000255}.
Tissue specificity:		Higher levels in roots than in shoots (PubMed:2143186). Expressed in epidermal and root cortex cells, in phloem, xylem and root hairs (PubMed:17483306). Detected in cotyledons, hypocotyls, roots and root hairs (PubMed:25267325). {ECO:0000269\|PubMed:17483306, ECO:0000269\|PubMed:2143186, ECO:0000269\|PubMed:25267325}.
Developmental stage:		Expressed on the surface of developing seeds and up to the early globular stage of embryo development. {ECO:0000269\|PubMed:20348108}.
Induction:		Up-regulated by low nitrate conditions. {ECO:0000269\|PubMed:25382626}.
Domain:		The C-terminus contains a R-domain composed of 2 autoinhibitory regions (863-885 and 904-919). {ECO:0000269\|PubMed:10353834}.
Ptm:		Phosphorylation at Thr-881 by PSY1R (PubMed:17651370, PubMed:25267325). This phosphorylation activates proton pumping (PubMed:25267325). Decreased phosphorylation in response to flg22 elicitation (PubMed:17651370). {ECO:0000269\|PubMed:17651370, ECO:0000269\|PubMed:25267325}.
Ptm:		Phosphorylation at Ser-899 is specifically induced by RALF1, thus leading to the inhibition of proton transport (PubMed:24458638). Increased phosphorylation in response to flg22 elicitation (PubMed:17651370). {ECO:0000269\|PubMed:17651370, ECO:0000269\|PubMed:24458638}.
Ptm:		Phosphorylation of Thr-947 induces the binding to 14-3-3 proteins, but phosphorylation of Ser-931 interfers with this binding no matter whether Thr-947 is phosphorylated or not (PubMed:10593986, PubMed:17483306). Decreased phosphorylation in response to flg22 elicitation (PubMed:17651370). {ECO:0000269\|PubMed:10593986, ECO:0000269\|PubMed:17483306, ECO:0000269\|PubMed:17651370}.
Ptm:		Abscisic acid induces dephosphorylation of AHA2 in etiolated seedlings, suppressing ATP hydrolysis and hypocotyl elongation. {ECO:0000269\|PubMed:24492258}.
Disruption phenotype:		No visible phenotype under normal growth conditions, due to the redudancy with AHA1. Aha1 and aha2 double mutants are embryo lethal. {ECO:0000269\|PubMed:20348108}.
Miscellaneous:		The catalytic mechanism involves at least four different enzyme conformational states named E1, E1P, E2P, and E2, with the E1P- E2P transition accompanying the transfer of ion across the membrane. E1P and E2P are phosphorylated intermediates. {ECO:0000305\|PubMed:10748244}.
Similarity:		Belongs to the cation transport ATPase (P-type) (TC 3.A.3) family. Type IIIA subfamily. {ECO:0000305}.