WORKLIST ENTRIES (1):
KCNQ3CHANNEL View alignment KCNQ3 voltage-gated potassium channel signature
Type of fingerprint: COMPOUND with 9 elements
Links:
PRINTS; PR00169 KCHANNEL; PR01459 KCNQCHANNEL; PR01460 KCNQ1CHANNEL
PRINTS; PR01461 KCNQ2CHANNEL
Creation date 14-NOV-2000
1. MILLER, C.
An overview of the potassium channel family.
GENOME BIOL. 1(4) 1-5 (2000).
2. ASHCROFT, F.M.
Voltage-gated K+ channels.
IN ION CHANNELS AND DISEASE, ACADEMIC PRESS, 2000, PP.111-116.
3. SANGUINETTI, M. C.
Maximal function of minimal K+ channel subunits.
TRENDS PHARMACOL.SCI. 21 199-201 (2000).
4. WANG Q., CURRAN, M.E., SPLAWSKI, I., BURN, T.C., MILLHOLLAND, J.M.,
VANRAAY, T.J., SHEN, J., TIMOTHY, K.W., VINCENT, G.M., DE JAGER, T.,
SCHWARTZ, P.J., TOUBIN, J.A., MOSS, A.J., ATKINSON, D.L., LANDES, G.M.,
CONNORS, T.D. AND KEATING, M.T.
Positional cloning of a novel potassium channel gene: KVLQT1 mutations
cause cardiac arrhythmias.
NAT.GENET. 12(1) 17-23 (1996).
5. BIERVERT, C., SCHROEDER, B.C., KUBISCH, C., BERKOVIC, S.F., PROPPING, P.,
JENTSCH, T.J. AND STEINLEIN, O.K.
A potassium channel mutation in neonatal human epilepsy.
SCIENCE 279 403-406 (1998).
6. SCHROEDER, B.C., KUBISCH, C., STEIN, V. AND JENTSCH, T.J.
Moderate loss of function of cyclic-AMP-modulated KCNQ2/KCNQ3 K+ channels
causes epilepsy.
NATURE 396 687-690 (1998).
Potassium ion (K+) channels are a structurally diverse group of proteins
that facilitate the flow of K+ ions across cell membranes. They are
ubiquitous, being present in virtually all cell types. Activation of K+
channels tends to hyperpolarise cells, reducing the membrane's electrical
resistance, dampening nervous activity. In eukaryotic cells, K+ channels
are involved in neural signalling and generation of the cardiac rhythm, and
act as effectors in signal transduction pathways involving G protein-
coupled receptors (GPCRs). In prokaryotic cells, they play a role in the
maintenance of ionic homeostasis [1].
Structurally, KCNQ channels belong to the subfamily of K+ channels whose
subunits contain 6 transmembrane (TM) domains: these are the voltage-gated
K+ channels, the KCNQ channels, the EAG-like K+ channels and 3 kinds of
Ca2+-activated K+ channel (BK, IK and SK) [2]. All K+ channels share a
characteristic sequence feature: a TMxTVGYG motif that resides between
the 2 C-terminal membrane-spanning helices, and forms the K+-selective
pore domain [1].
KCNQ channels differ from other voltage-gated 6 TM helix channels, chiefly
in that they possess no tetramerisation domain. Consequently, they rely on
interaction with accessory subunits, or form heterotetramers with other
members of the family [3]. Currently, 5 members of the KCNQ family are
known. These have been found to be widely distributed within the body,
having been shown to be expressed in the heart, brain, pancreas, lung,
placenta and ear. They were initially cloned as a result of a search for
proteins involved in cardiac arhythmia. Subsequently, mutations in other
KCNQ family members have been shown to be responsible for some forms of
hereditary deafness [4] and benign familial neotnatal epilepsy [5].
The KCNQ3 channel subunit is thought to form active channels by hetero-
tetramerisation with KCNQ2, although some K+ channel activity does result
from the expression of KCNQ3 alone [6]. Channel function is modulated by
phosphorylation; experiments have demonstrated that an increase in
intracellular cAMP concentration can enhance channel activity [2].
Frameshift mutations in both KCNQ2 and KCNQ3 are associated with benign
familial neonatal epilepsy [6], a disorder in which infants suffer
convulsions within the first 3 days of life. These symptoms usually
disappear after about 3 months, but affected individuals have a higher
than average chance of subsequently developing epilepsy (10-15%) in later
life [5].
KCNQ3CHANNEL is a 9-element fingerprint that provides a signature for the
KCNQ3 voltage-gated potassium channel subtype. The fingerprint was derived
from an initial alignment of 3 sequences: the motifs were drawn from
conserved regions spanning virtually the full alignment length, focusing
on those sections that characterise the KCNQ3 channel but distinguish it
from other members of the K+ channel superfamily - motif 1 lies within the
N-terminal intracellular region; motif 2 encodes the putative extracellular
loop between TM domains 1 and 2; motif 3 spans the C-terminal half of
putative TM domain 3; motif 4 encodes the putative cytoplasmic loop between
TM domains 4 and 5; and motifs 5-9 reside within the C-terminal intra-
cellular region. A single iteration on SPTR39_14f was required to reach
convergence, no further sequences being identified beyond the starting set.
SUMMARY INFORMATION
3 codes involving 9 elements
0 codes involving 8 elements
0 codes involving 7 elements
0 codes involving 6 elements
0 codes involving 5 elements
0 codes involving 4 elements
0 codes involving 3 elements
0 codes involving 2 elements
COMPOSITE FINGERPRINT INDEX
9| 3 3 3 3 3 3 3 3 3
8| 0 0 0 0 0 0 0 0 0
7| 0 0 0 0 0 0 0 0 0
6| 0 0 0 0 0 0 0 0 0
5| 0 0 0 0 0 0 0 0 0
4| 0 0 0 0 0 0 0 0 0
3| 0 0 0 0 0 0 0 0 0
2| 0 0 0 0 0 0 0 0 0
--+----------------------------------------------
| 1 2 3 4 5 6 7 8 9
True positives..
O88944 Q9Z240 CIQ3_HUMAN
PROTEIN TITLES
O88944 POTASSIUM CHANNEL - Rattus norvegicus (Rat).
Q9Z240 POTASSIUM CHANNEL - Rattus norvegicus (Rat).
CIQ3_HUMAN VOLTAGE-GATED POTASSIUM CHANNEL PROTEIN KQT-LIKE 3 - Homo sa
SCAN HISTORY
SPTR39_14f 1 50 NSINGLE
INITIAL MOTIF SETS
KCNQ3CHANNEL1 Length of motif = 14 Motif number = 1
KCNQ3 voltage-gated potassium channel motif I - 1
PCODE ST INT
QGIGLLAKTPLSRP CIQ3_HUMAN 83 83
QGIGLLAKTPLSRP O88944 84 84
QGIGLLAKTPLSRP Q9Z240 46 46
KCNQ3CHANNEL2 Length of motif = 12 Motif number = 2
KCNQ3 voltage-gated potassium channel motif II - 1
PCODE ST INT
LGCLILAVLTTF CIQ3_HUMAN 134 37
LGCLILAVLTTF O88944 135 37
LGCLILAVLTTF Q9Z240 97 37
KCNQ3CHANNEL3 Length of motif = 10 Motif number = 3
KCNQ3 voltage-gated potassium channel motif III - 1
PCODE ST INT
SVPVVAVGNQ CIQ3_HUMAN 209 63
SVPVVAVGNQ O88944 210 63
SVPVVAVGNQ Q9Z240 172 63
KCNQ3CHANNEL4 Length of motif = 14 Motif number = 4
KCNQ3 voltage-gated potassium channel motif IV - 1
PCODE ST INT
VPEVDAQGEEMKEE CIQ3_HUMAN 286 67
VPEMDAQGEEMKEE O88944 287 67
VPEMDAQGEEMKEE Q9Z240 249 67
KCNQ3CHANNEL5 Length of motif = 13 Motif number = 5
KCNQ3 voltage-gated potassium channel motif V - 1
PCODE ST INT
PVGLNNKERFRTA CIQ3_HUMAN 463 163
PVGLNNKERFRTA O88944 464 163
PVGLNNKERFRTA Q9Z240 426 163
KCNQ3CHANNEL6 Length of motif = 18 Motif number = 6
KCNQ3 voltage-gated potassium channel motif VI - 1
PCODE ST INT
PSTPKHKKSQKGSAFTFP CIQ3_HUMAN 577 101
PSTPKHKKSQKGSAFTYP O88944 578 101
PSTPKHKKSQKGSAFTYP Q9Z240 540 101
KCNQ3CHANNEL7 Length of motif = 20 Motif number = 7
KCNQ3 voltage-gated potassium channel motif VII - 1
PCODE ST INT
TIICNYSETGPPEPPYSFHQ CIQ3_HUMAN 682 87
TIICNYSESGPPDPPYSFHQ O88944 683 87
TIICNYSESGPPDPPYSFHQ Q9Z240 645 87
KCNQ3CHANNEL8 Length of motif = 17 Motif number = 8
KCNQ3 voltage-gated potassium channel motif VIII - 1
PCODE ST INT
KVQATPPSSATTYVERP CIQ3_HUMAN 729 27
KAQANLPSSGSTYAERP O88944 730 27
KAQANLPSSGSTYAERP Q9Z240 692 27
KCNQ3CHANNEL9 Length of motif = 16 Motif number = 9
KCNQ3 voltage-gated potassium channel motif IX - 1
PCODE ST INT
DSRVSCHSQADLQGPY CIQ3_HUMAN 755 9
DSCVSYHSQTELQGPY O88944 756 9
DSCVSYHSQTELQGPY Q9Z240 718 9
FINAL MOTIF SETS
KCNQ3CHANNEL1 Length of motif = 14 Motif number = 1
KCNQ3 voltage-gated potassium channel motif I - 1
PCODE ST INT
QGIGLLAKTPLSRP O88944 84 84
QGIGLLAKTPLSRP Q9Z240 46 46
QGIGLLAKTPLSRP CIQ3_HUMAN 83 83
KCNQ3CHANNEL2 Length of motif = 12 Motif number = 2
KCNQ3 voltage-gated potassium channel motif II - 1
PCODE ST INT
LGCLILAVLTTF O88944 135 37
LGCLILAVLTTF Q9Z240 97 37
LGCLILAVLTTF CIQ3_HUMAN 134 37
KCNQ3CHANNEL3 Length of motif = 10 Motif number = 3
KCNQ3 voltage-gated potassium channel motif III - 1
PCODE ST INT
SVPVVAVGNQ O88944 210 63
SVPVVAVGNQ Q9Z240 172 63
SVPVVAVGNQ CIQ3_HUMAN 209 63
KCNQ3CHANNEL4 Length of motif = 14 Motif number = 4
KCNQ3 voltage-gated potassium channel motif IV - 1
PCODE ST INT
VPEMDAQGEEMKEE O88944 287 67
VPEMDAQGEEMKEE Q9Z240 249 67
VPEVDAQGEEMKEE CIQ3_HUMAN 286 67
KCNQ3CHANNEL5 Length of motif = 13 Motif number = 5
KCNQ3 voltage-gated potassium channel motif V - 1
PCODE ST INT
PVGLNNKERFRTA O88944 464 163
PVGLNNKERFRTA Q9Z240 426 163
PVGLNNKERFRTA CIQ3_HUMAN 463 163
KCNQ3CHANNEL6 Length of motif = 18 Motif number = 6
KCNQ3 voltage-gated potassium channel motif VI - 1
PCODE ST INT
PSTPKHKKSQKGSAFTYP O88944 578 101
PSTPKHKKSQKGSAFTYP Q9Z240 540 101
PSTPKHKKSQKGSAFTFP CIQ3_HUMAN 577 101
KCNQ3CHANNEL7 Length of motif = 20 Motif number = 7
KCNQ3 voltage-gated potassium channel motif VII - 1
PCODE ST INT
TIICNYSESGPPDPPYSFHQ O88944 683 87
TIICNYSESGPPDPPYSFHQ Q9Z240 645 87
TIICNYSETGPPEPPYSFHQ CIQ3_HUMAN 682 87
KCNQ3CHANNEL8 Length of motif = 17 Motif number = 8
KCNQ3 voltage-gated potassium channel motif VIII - 1
PCODE ST INT
KAQANLPSSGSTYAERP O88944 730 27
KAQANLPSSGSTYAERP Q9Z240 692 27
KVQATPPSSATTYVERP CIQ3_HUMAN 729 27
KCNQ3CHANNEL9 Length of motif = 16 Motif number = 9
KCNQ3 voltage-gated potassium channel motif IX - 1
PCODE ST INT
DSCVSYHSQTELQGPY O88944 756 9
DSCVSYHSQTELQGPY Q9Z240 718 9
DSRVSCHSQADLQGPY CIQ3_HUMAN 755 9
User query: Display/Full Code "KCNQ3CHANNEL"