Novel rat voltage-gated potassium channel

Abstract

Disclosed herein are nucleic acid and polypeptide sequences of a novel rat voltage-gated potassium channel, KCNQ5. Also disclosed herein are methods related to the use of the aforementioned potassium channel.

1 . (canceled) 
     
     
         2 . An isolated polynucleotide comprising a polynucleotide selected from the group consisting of:
 (a) a polynucleotide comprising SEQ ID NO:1;   (b) a polynucleotide encoding SEQ ID NO:2;   (c) a polynucleotide encoding a polypeptide having at least about 99% sequence identity to the amino acid sequence of SEQ ID NO:2, said polypeptide comprising a KCNQ5 alpha subunit of a potassium channel and being capable of forming, with at least one additional KCNQ alpha subunit, a KCNQ potassium channel having the characteristic of voltage gating; and   (d) a polynucleotide which is complementary to (a), (b), or (c).   
     
     
         3 . The isolated polynucleotide of  claim 2 , wherein the isolated polynucleotide is DNA. 
     
     
         4 . The isolated polynucleotide of  claim 2 , wherein the isolated polynucleotide is RNA. 
     
     
         5 . The isolated polynucleotide of  claim 2  comprising nucleotides 257-2008 of SEQ ID NO:1. 
     
     
         6 . An isolated polynucleotide fragment comprising at least 12, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 75, 100, 200, 300, 400, 500, 600, or 700 contiguous nucleotides of the sense sequence of the isolated polynucleotide of  claim 5 . 
     
     
         7 . A primer or probe comprising the isolated polynucleotide fragment of  claim 6 . 
     
     
         8 - 10 . (canceled) 
     
     
         11 . A vector comprising the isolated polynucleotide of  claim 2 . 
     
     
         12 . The vector of  claim 11 , wherein the vector is a plasmid. 
     
     
         13 . The vector of  claim 11 , wherein the vector is an expression vector. 
     
     
         14 . A host cell transformed with the vector of  claim 11 . 
     
     
         15 . The host cell of  claim 14  which is a prokaryotic cell. 
     
     
         16 . The host cell of  claim 15 , wherein the prokaryotic cell is an  E. coli  cell. 
     
     
         17 . The host cell of  claim 14  which is a eukaryotic cell. 
     
     
         18 . The host cell of  claim 17 , wherein the eukaryotic cell is an insect cell, a yeast cell, a  Xenopus laevis  oocyte, or a mammalian cell. 
     
     
         19 - 23 . (canceled) 
     
     
         24 . An isolated polynucleotide encoding a fusion protein, said fusion protein comprising
 (a) a polypeptide comprising a KCNQ5 alpha subunit of a potassium channel, wherein the polypeptide:
 (i) has at least 99% sequence identity to the amino acid sequence of SEQ ID NO:2: and 
 (ii) is capable of forming, with at least one additional KCNQ alpha subunit, a KCNQ potassium channel having the characteristic of voltage-gating; 
   (b) operably linked to a second, non-rKCNQ5 polypeptide.   
     
     
         25 - 48 . (canceled) 
     
     
         49 . A method of screening for agents, the method comprising:
 (a) contacting a cell with an agent; and   (b) determining the level of expression of the polynucleotide of  claim 2 ;   
       wherein detection of a decrease or an increase in expression of said polynucleotide is indicative of an agent being a modulator of rKCNQ5. 
     
     
         50 - 63 . (canceled) 
     
     
         64 . A method for detecting expression of KCNQ5 comprising detecting mRNA encoding KCNQ5 in a sample from a cell or tissue suspected of expressing KCNQ5 with the probe of  claim 7 . 
     
     
         65 . The method of  claim 64 , wherein the tissue is brain, skeletal muscle, or urinary bladder. 
     
     
         66 . A method for determining whether a KCNQ5 gene has been mutated or deleted comprising detecting, in a sample of cells or tissue from a subject, the presence or absence of a genetic alteration characterized by at least one of an alteration affecting the integrity of a gene encoding a KCNQ5 protein or the misexpression of a KCNQ5 gene, wherein the detecting step is performed with the probe or primer of  claim 7 . 
     
     
         67 . The method of  claim 66 , wherein the tissue is brain, skeletal muscle, or urinary bladder. 
     
     
         68 - 71 . (canceled) 
     
     
         72 . A method of producing a KCNQ5 polypeptide comprising:
 (a) culturing a transformed host cell comprising the expression vector of  claim 13  in a suitable medium such that a KCNQ5 polypeptide is produced; and   (b) optionally, recovering the KCNQ5 polypeptide of step (a).   
     
     
         73 - 84 . (canceled) 
     
     
         85 . A method for the production of a KCNQ5 polypeptide comprising:
 (a) providing a homogenous population of cells;   (b) introducing into the population of cells an isolated genomic construct comprising a promoter operably linked to an rKCNQ5 targeting sequence, wherein
 (i) the rKCNQ5 targeting sequence comprises at least 1000 contiguous nucleotides of the polynucleotide of  claim 2 ; 
 (ii) the promoter is heterologous to the KCNQ5 target gene; and 
 (iii) following recombination the promoter controls transcription of an mRNA that encodes a KCNQ5 polypeptide; and 
   (c) incubating the population of cells under conditions which cause expression of the KCNQ5 polypeptide.   
     
     
         86 . The method of  claim 85 , wherein the rKCNQ5 targeting sequence comprises at least 1000 contiguous nucleotides from nucleotides 257-2008 of SEQ ID NO:1. 
     
     
         87 - 95 . (canceled)