SPRINT Home UMBER Home Contents Standard Search Advanced Search Relation Search

==SPRINT==> PRINTS View



  selected as


PR01516

Identifier
KV41CHANNEL  [View Relations]  [View Alignment]  
Accession
PR01516
No. of Motifs
8
Creation Date
19-JUN-2001
Title
Kv4.1 voltage-gated K+ channel signature
Database References
PRINTS; PR00169 KCHANNEL; PR01491 KVCHANNEL; PR01497 SHALCHANNEL
Literature References
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.97-123.
 
3. SANSOM, M.S.
Putting the parts together.
CURR.BIOL. 9(19) R738-R741 (1999).   
 
4. CONLEY, E.C. AND BRAMMER, W.J.
Shal.
IN THE ION CHANNEL FACTSBOOK, VOLUME IV, ACADEMIC PRESS, 1999, PP.617-646.

Documentation
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, Kv channels belong to the subfamily of K+ channels whose
subunits contain 6 transmembrane (TM) domains: these are the voltage-
gated K+ (Kv) channels, the KCNQ channels, the EAG-like K+ channels and
3 kinds of Ca2+-activated K+ channels (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 [1-2].
     
The Kv family can be divided into 4 subfamilies on the basis of sequence
similarity and function: Shaker (Kv1), Shab (Kv2), Shaw (Kv3) and Shal 
(Kv4). All consist of pore-forming alpha subunits that associate with 
different types of beta subunit. To form a functional K+ channel pore,
4 alpha subunits and 4 beta subunits are required. The alpha subunits
have 6 well-conserved TM domains, a pore loop region and variable length
N- and C-termini. TM domains 5 and 6, and the loop region, form the K+ 
channel pore through which the K+ ions pass [3].
     
The first Shal (Kv4) sequence was found in Drosophila. Several vertebrate
K+ channels with similar amino acid sequences were subsequently found and,
together with the Drosophila Shal channel, now constitute the Shal (Kv4)
family. These channels support outward K+-selective currents and are
inhibited by free fatty acids [4]. The Shal family can be further divided 
into 3 families, designated Kv4.1, Kv4.2 and Kv4.3.
 
Kv4.1 channels are expressed in the heart, brain, liver, kidney and
pancreas. Association with specific subunits increases their surface
expression. Essential to their function are the N- and C-termini, which
work together to control the inactivation of these channels [4].
 
KV41CHANNEL is an 8-element fingerprint that provides a signature for the
Kv4.1 voltage-gated K+ channel. 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 Kv4.1 channels but distinguish them from other members
of the Shal channel family - motifs 1 and 2 reside at the N-terminus; and
motifs 3-8 span the C-terminus. A single iteration on SPTR39_15f was
required to reach convergence, no further sequences being identified beyond
the starting set.
Summary Information
3 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 Feature Index
833333333
700000000
600000000
500000000
400000000
300000000
200000000
12345678
True Positives
O75671        Q03719        Q9NSA2        
Sequence Titles
O75671      SHAL-TYPE POTASSIUM CHANNEL (VOLTAGE-GATED POTASSIUM CHANNEL KV4.1) - Homo sapiens (Human). 
Q03719 POTASSIUM CHANNEL PROTEIN - Mus musculus (Mouse).
Q9NSA2 SHAL-TYPE POTASSIUM CHANNEL (KV4.1) - Homo sapiens (Human).
Scan History
SPTR39_15f 1  130  NSINGLE    
Initial Motifs
Motif 1  width=10
Element Seqn Id St Int Rpt
FYDADSGEYF O75671 74 74 -
FYDADSGEYF Q9NSA2 74 74 -
FYDAESGEYF Q03719 74 74 -

Motif 2 width=12
Element Seqn Id St Int Rpt
EDEEAEQAGDGP O75671 149 65 -
EDEEAEQAGDGP Q9NSA2 149 65 -
EDEEAEQAGEGP Q03719 149 65 -

Motif 3 width=12
Element Seqn Id St Int Rpt
QYKQNGGLEDSG O75671 448 287 -
QYKQNGGLEDSG Q9NSA2 448 287 -
QYKQNGGLEDSG Q03719 448 287 -

Motif 4 width=17
Element Seqn Id St Int Rpt
GEEQALCVRNRSAFEQQ O75671 461 1 -
GEEQALCVRNRSAFEQQ Q9NSA2 461 1 -
GDGQMLCVRSRSAFEQQ Q03719 461 1 -

Motif 5 width=13
Element Seqn Id St Int Rpt
GSMQELDMLAGLR O75671 554 76 -
GSMQELDMLAGLR Q9NSA2 554 76 -
GSMQELDTLAGLR Q03719 554 76 -

Motif 6 width=14
Element Seqn Id St Int Rpt
PHDSLDLNCDSRDF O75671 581 14 -
PHDSLDLNCDSRDF Q9NSA2 581 14 -
PHDSLDLNCDSRDF Q03719 581 14 -

Motif 7 width=12
Element Seqn Id St Int Rpt
QPSSPGGGGRAG O75671 613 18 -
QPSSPGGGGRAG Q9NSA2 613 18 -
QPSSPSGGGGSG Q03719 613 18 -

Motif 8 width=15
Element Seqn Id St Int Rpt
GTPCLFPETVKISSL O75671 633 8 -
GTPCLFPETVKISSL Q9NSA2 633 8 -
GTPCLLPETVKISSL Q03719 637 12 -
Final Motifs
Motif 1  width=10
Element Seqn Id St Int Rpt
FYDADSGEYF O75671 74 74 -
FYDADSGEYF Q9NSA2 74 74 -
FYDAESGEYF Q03719 74 74 -

Motif 2 width=12
Element Seqn Id St Int Rpt
EDEEAEQAGDGP O75671 149 65 -
EDEEAEQAGDGP Q9NSA2 149 65 -
EDEEAEQAGEGP Q03719 149 65 -

Motif 3 width=12
Element Seqn Id St Int Rpt
QYKQNGGLEDSG O75671 448 287 -
QYKQNGGLEDSG Q9NSA2 448 287 -
QYKQNGGLEDSG Q03719 448 287 -

Motif 4 width=17
Element Seqn Id St Int Rpt
GEEQALCVRNRSAFEQQ O75671 461 1 -
GEEQALCVRNRSAFEQQ Q9NSA2 461 1 -
GDGQMLCVRSRSAFEQQ Q03719 461 1 -

Motif 5 width=13
Element Seqn Id St Int Rpt
GSMQELDMLAGLR O75671 554 76 -
GSMQELDMLAGLR Q9NSA2 554 76 -
GSMQELDTLAGLR Q03719 554 76 -

Motif 6 width=14
Element Seqn Id St Int Rpt
PHDSLDLNCDSRDF O75671 581 14 -
PHDSLDLNCDSRDF Q9NSA2 581 14 -
PHDSLDLNCDSRDF Q03719 581 14 -

Motif 7 width=12
Element Seqn Id St Int Rpt
QPSSPGGGGRAG O75671 613 18 -
QPSSPGGGGRAG Q9NSA2 613 18 -
QPSSPSGGGGSG Q03719 613 18 -

Motif 8 width=15
Element Seqn Id St Int Rpt
GTPCLFPETVKISSL O75671 633 8 -
GTPCLFPETVKISSL Q9NSA2 633 8 -
GTPCLLPETVKISSL Q03719 637 12 -