Q9QYW1
uniprot
Q9QYW1
canonical
amino_acid_sequence
MGGELVTGLGALRRRKRLLEQEKRVAGWALVLAGTGIGLMVLHAEMLWFLGCKWVLYLLLVKCLITLSTAFLLCLIVVFHAKEVQLFMTDNGLRDWRVALTRRQVAQILLELLVCGVHPVPLRSPHCTLAGEATDSQAWPGFLGEGEALLSLAMLLRLYLVPRAVLLRSGVLLNASYRSIGALNQVRFRHWFVAKLYMNTHPGRLLLGLTLGLWLTTAWVLSVAERQAVNATGHLTDTLWLIPITFLTIGYGDVVPGTLWGKIVCLCTGVMGVCCTALLVAVVARKLEFNKAEKHVHNFMMDIHYAKEMKESAARLLQEAWMYYKHTRRKDSRAARRHQRKMLAAIHTFRQVRLKHRKLREQVNSMVDISKMHMILCDLQLGLSASHLALEKRIDGLAGKLDALTELLSTALQQQQPPEPIQEAT
uniprot
proteins
function
FUNCTION: Intermediate conductance calcium-activated potassium channel that mediates the voltage-independent transmembrane transfer of potassium across the cell membrane through a constitutive interaction with calmodulin which binds the intracellular calcium allowing its opening (PubMed:10532960). The current is characterized by a voltage-independent activation, an intracellular calcium concentration increase-dependent activation and a single-channel conductance of about 25 picosiemens (PubMed:10532960). Also presents an inwardly rectifying current, thus reducing its already small outward conductance of potassium ions, which is particularly the case when the membrane potential displays positive values, above + 20 mV (By similarity). Controls calcium influx during vascular contractility by being responsible of membrane hyperpolarization induced by vasoactive factors in proliferative vascular smooth muscle cell types (PubMed:10532960). Following calcium influx, the consecutive activation of KCNN4 channel leads to a hyperpolarization of the cell membrane potential and hence an increase of the electrical driving force for further calcium influx promoting sustained calcium entry in response to stimulation with chemotactic peptides. Required for maximal calcium influx and proliferation during the reactivation of naive T-cells (By similarity). Plays a role in the late stages of EGF-induced macropinocytosis through activation by PI(3)P (By similarity). {ECO:0000250|UniProtKB:O15554, ECO:0000269|PubMed:10532960}.
uniprot
proteins
mass_dalton
47767
uniprot
proteins
post_translational_modification
PTM: Phosphorylation at His-356 by NDKB activates the intermediate conductance calcium-activated potassium channel activity, and conversely its dephosphorylation by PHPT1 inhibits this activity. {ECO:0000250|UniProtKB:O15554}.
uniprot
proteins
protein_family
KCa3.1/KCNN4 subfamily
uniprot
proteins
protein_family
Potassium channel KCNN family
uniprot
proteins
pubmed
10519135
uniprot
proteins
pubmed
10532960
uniprot
proteins
sequence_length
425
uniprot
proteins
subcellular_location
SUBCELLULAR LOCATION: Cell membrane {ECO:0000250|UniProtKB:O15554}; Multi-pass membrane protein {ECO:0000255}. Cell projection, ruffle membrane {ECO:0000250|UniProtKB:O15554}. Note=Targeted to membrane ruffles after EGF stimulation. {ECO:0000250|UniProtKB:O15554}.
uniprot
proteins
transmembrane_region
TRANSMEM 30..50; /note="Helical; Name=Segment S1"; /evidence="ECO:0000255"; TRANSMEM 59..79; /note="Helical; Name=Segment S2"; /evidence="ECO:0000255"; TRANSMEM 105..121; /note="Helical; Name=Segment S3"; /evidence="ECO:0000255"; TRANSMEM 141..161; /note="Helical; Name=Segment S4"; /evidence="ECO:0000255"; TRANSMEM 205..225; /note="Helical; Name=Segment S5"; /evidence="ECO:0000255"; TRANSMEM 263..283; /note="Helical; Name=Segment S6"; /evidence="ECO:0000255
uniprot
proteins