Low-molecular weight peptides inhibiting ion channel activity

Abstract

It is intended to provide novel polypeptides which specifically inhibit the activity of a mechano-sensitive channel; and mechano-sensitive channel inhibitors or remedies for atrial fibrillation containing these polypeptides or salts thereof. The above objects can be achieved by using polypeptides having amino acid sequences represented by SEQ ID NO: 1 (TVP003), SEQ ID NO:2 (TVP004) and SEQ ID NO:3 (TVP005), salts of these polypeptides, and mechano-sensitive channel inhibitors or remedies for atrial fibrillation containing the same.

1 . A purified polypeptide or salt thereof, the polypeptide consisting of:
 an amino acid of SEQ ID NO: 2 an amino acid of SEQ ID NO: 16 or an amino acid of SEQ ID NO: 17.   
     
     
         2 . The polypeptide or salts in accordance with  claim 1 , wherein the polypeptide having an intermolecular disulfide bond between two of the cysteines contained in the amino acid of SEQ ID NO: 2, the amino acid of SEQ ID NO: 16 or the amino acid of SEQ ID NO: 17. 
     
     
         3 . A purified polypeptide or salts thereof, the polypeptide consisting of:
 an amino acid of SEQ ID NO: 2 of which one or two amino acids have been deleted, one or two amino acids have been substituted, one or two amino acids have been inserted or one or two amino acids have been added;   the polypeptide having an intermolecular disulfide bond between two of the cysteines; and   the polypeptide having mechano-sensitive channel inhibiting activity.   
     
     
         4 . A mechano-sensitive channel inhibitor comprising the purified polypeptide or salt thereof as described in  claim 1 . 
     
     
         5 . A mechano-sensitive channel inhibitor comprising the purified polypeptide or salt thereof as described in  claim 2 . 
     
     
         6 . A mechano-sensitive channel inhibitor comprising the purified polypeptide or salt thereof as described in  claim 3 . 
     
     
         7 . A remedy of atrial fibrillation comprising the step of administering one of the purified polypeptide or salts thereof described in  claim 1 . 
     
     
         8 . A remedy of atrial fibrillation comprising the step of administering one of the purified polypeptide or salts thereof described in  claim 2 . 
     
     
         9 . A remedy of atrial fibrillation comprising the step of administering one of the purified polypeptide or salts thereof described in  claim 3 . 
     
     
         10 . A polynucleotide consisting of the polynucleotide that encodes the polypeptide described in  claim 1 . 
     
     
         11 . A polynucleotide consisting of the polynucleotide that encodes the polypeptide described in  claim 2 . 
     
     
         12 . A polynucleotide consisting of the polynucleotide that encodes the polypeptide described in  claim 3 . 
     
     
         13 . A recombinant vector comprising the polynucleotide described in  claim 10 . 
     
     
         14 . A recombinant vector comprising the polynucleotide described in  claim 11 . 
     
     
         15 . A recombinant vector comprising the polynucleotide described in  claim 12 . 
     
     
         16 . A transformant transformed with the recombinant vector described in  claim 10 . 
     
     
         17 . A transformant transformed with the recombinant vector described in  claim 11 . 
     
     
         18 . A transformant transformed with the recombinant vector described in  claim 12 .