Gene carrier

Abstract

Disclosed is a gene carrier composed of a hydrogen-bonding polymer having a polymer chain with hydrogen-bonding sites formed on the polymer chain, in which the polymer chain has a conformation similar to the conformation of a nucleic acid, and particularly, the polymer chain has helix parameters similar to the helix parameters of a nucleic acid of a helix structure. In a preferred embodiment, the hydrogen-bonding polymer is composed of β-1,3-glucan such as schizophyllan. The carrier can be expected to be applied as a vector and a separator for nucleic acids because it is capable of interacting with a nucleic acid to form a complex with the nucleic acid and thus carrying the nucleic acid.

1 - 11 . (canceled) 
     
     
         12 . An isolated nucleic acid-polymer complex composed of a nucleic acid and a hydrogen-bonding polymer having a polymer chain comprising a naturally occurring β-1,3-glucan with hydrogen-bonding sites formed on the polymer chain, the hydrogen bonding sites being formed on the polymer chain by unbinding a β-1,3-glucan to form a single stranded β-1,3-glucan capable of forming a complex with a single stranded nucleic acid, and, when being combined with the single stranded β-1,3-glucan, the nucleic acid being a helical compound, and said polymer chain, when in aqueous solution, having helix parameters similar to the helix parameters of the single stranded nucleic acid, and wherein the nucleic acid is bonded to the hydrogen-bonding polymer through the hydrogen-bonding sites. 
     
     
         13 . The isolated nucleic acid polymer complex of  claim 12 , wherein the naturally occurring β-1,3-glucan is schizophyllan, curdlan, lentinan, pachyman, griffollan or scleroglucan. 
     
     
         14 . The isolated nucleic acid polymer complex of  claim 13 , wherein the β-1,3-glucan is schizophyllan. 
     
     
         15 . The isolated nucleic acid polymer complex of  claim 12 , wherein the similar helix parameters include the polymer chain having an h/R value in a range of 2 to 4 Å. 
     
     
         16 . The isolated nucleic acid polymer complex of  claim 12 , wherein the nucleic acid comprises RNA or DNA. 
     
     
         17 . The isolated nucleic acid polymer complex of  claim 12 , wherein the hydrogen-bonding polymer has a weight-average molecular weight of 2000 or more. 
     
     
         18 . The isolated nucleic acid polymer complex of  claim 17 , wherein the hydrogen-bonding polymer has a weight-average molecular weight of 6000 or more. 
     
     
         19 . An aqueous solution comprising the isolated nucleic acid-polymer complex of  claim 12 . 
     
     
         20 . A method of forming an isolated nucleic acid-polymer complex composed of a nucleic acid and a hydrogen bonding polymer having a polymer chain comprising a β-1,3-glucan with hydrogen-bonding sites on the polymer chain, comprising:
 unbinding a triple helix structure comprising a naturally occurring β-1,3-glucan to form a single stranded β-1,3-glucan comprising a hydrogen bonding polymer having a polymer chain with hydrogen-bonding sites formed on the polymer chain; and 
 combining the hydrogen bonding polymer with an aqueous solution of a single stranded nucleic acid to form the complex, the polymer chain, when in the aqueous solution, having helix parameters similar to the helix parameters of the single stranded nucleic acid, wherein the single stranded nucleic acid and the hydrogen bonding polymer are helical compounds, whereby the nucleic acid is bonded to the hydrogen bonding polymer through the hydrogen-bonding sites. 
 
     
     
         21 . The method of  claim 20 , wherein the naturally occurring β-1,3-glucan is schizophyllan, curdlan, lentinan, pachyman, griffollan or scleroglucan. 
     
     
         22 . The method of  claim 20 , wherein the similar helix parameters include the polymer chain having an h/R value in a range of 2 to 4 Å. 
     
     
         23 . The method of  claim 20 , wherein the nucleic acid comprises RNA or DNA. 
     
     
         24 . The method of  claim 20 , wherein the hydrogen-bonding polymer has a weight-average molecular weight of 2000 or more. 
     
     
         25 . The method of  claim 20 , wherein the unbinding of the triple helix structure includes dissolving the β-1,3-glucan in a solvent. 
     
     
         26 . The method of  claim 25 , wherein the solvent comprises DMSO. 
     
     
         27 . The method of  claim 20 , further comprising, prior to the unbinding, linking an antisense DNA to the nucleic acid. 
     
     
         28 . An isolated nucleic acid-polymer complex composed of a nucleic acid and a hydrogen bonding polymer having a polymer chain with hydrogen-bonding sites on the polymer chain, wherein the nucleic acid is bonded to the hydrogen bonding polymer through the hydrogen-bonding sites, the polymer chain having a twining direction which is the same as that of the nucleic acid, the hydrogen bonding polymer being partially or wholly composed of a naturally occurring β-1,3-glucan and the nucleic acid being bonded comprising a single-stranded nucleic acid comprising residues forming a helical compound. 
     
     
         29 . The isolated nucleic acid polymer complex of  claim 28 , wherein the similar helix parameters include the polymer chain having an h/R value in a range of 2 to 4 Å. 
     
     
         30 . An aqueous solution comprising the isolated nucleic acid-polymer complex of  claim 28 . 
     
     
         31 . An isolated nucleic acid-polymer complex composed of a nucleic acid and a hydrogen bonding polymer having a polymer chain, the hydrogen bonding polymer consisting of β-1,3-glucan, the complex being formed by a method comprising:
 unbinding a triple helix structure comprising a naturally occurring β-1,3-glucan to form a single strand comprising a hydrogen bonding polymer having a polymer chain with hydrogen-bonding sites on the polymer chain; and 
 combining the hydrogen bonding polymer with an aqueous solution of a single stranded nucleic acid to form the complex through the hydrogen-bonding sites on the polymer chain, the nucleic acid being a helical compound which has helix parameters similar to that of the hydrogen bonding polymer. 
 
     
     
         32 . The isolated nucleic acid-polymer complex of  claim 31 , wherein the unbinding of the triple helix structure includes dissolving the β-1,3-glucan in a solvent. 
     
     
         33 . The isolated nucleic acid-polymer complex of  claim 31 , comprising an antisense DNA linked to the nucleic acid which is a helical compound.