Method for secretory production of glycoprotein having human-type sugar chain using plant cell

Abstract

A method for the secretory production of a glycoprotein having a human-type sugar chain, comprising a step of introducing a gene of an enzyme capable of performing a transfer reaction of a galactose residue to a non-reducing terminal acetylglucosamine residue, and a gene of heterologous glycoprotein, to obtain a transformed plant cell, a step of culturing the plant cell, and a step of recovering the culture medium of the plant cell.

1 . A method for the secretory production of a glycoprotein having a human-type sugar chain from a plant cell, the method comprising: 
 a) introducing into said plant cell a first heterologous nucleic acid sequence encoding an enzyme that is capable of performing a transfer reaction of a galactose residue to a non-reducing terminal acetylglucosamine residue;    b) introducing into said plant cell a second nucleic acid residue encoding a heterologous glycoprotein; and,    c) culturing said plant cell such that the heterologous glycoprotein is secreted from said plant cell.    
     
     
         2 . The method of  claim 1 , wherein said heterologous glycoprotein comprises a core sugar chain and an outer sugar chain, said core sugar chain comprises a plurality of mannose and acetylglucosamines, and said outer sugar chain comprises a terminal sugar chain moiety containing a non-reducing terminal galactose.  
     
     
         3 . The method of  claim 2  wherein said outer sugar chain has a linear structure.  
     
     
         4 . The method of  claim 2  wherein said outer sugar chain has a branched structure.  
     
     
         5 . The method of  claim 4  wherein said branched outer sugar chain is a mono-, bi, tri, or tetra-structure.  
     
     
         6 . The method of  claim 1  wherein said glycoprotein is free of fucose or xylose.  
     
     
         7 . The method of  claim 1  further comprising a step of recovering the secreted glycoprotein.  
     
     
         8 . A transgenic plant cell comprising a first introduced nucleic acid sequence encoding an enzyme capable of performing a transfer reaction of a galactose residue to a non-reducing terminal acetylglucosamine and a second introduced nucleic acid residue encoding a heterologous glycoprotein, wherein said enzyme adds a sugar chain comprising a core sugar chain and an outer sugar chain, said core sugar chain substantially comprises a plurality of mannoses and acetylglucosamines, and said outer sugar chain has a terminal sugar chain moiety containing a non-reducing terminal galactose and wherein said transgenic plant cell secretes said heterologous glycoprotein.  
     
     
         9 . A transgenic plant cell according to  claim 8  wherein said heterologous glycoprotein comprises a galactose residue.  
     
     
         10 . A transgenic plant cell according to  claim 8  wherein said heterologous glycoprotein is free of β1,2 xylose or α1,3 fucose.  
     
     
         11 . A transgenic plant cell according to  claim 8  wherein said heterologous glycoprotein comprises a galactose residue added to an N-linked sugar of (N-acetylglucosamine) 1-2 (Mannose) 2-5 (N-acetylglucosamine) 2  selected from the group consisting of GlcNAc 1 Man 3 GlcNAc 2 , GlcNAc 1 Man 5 GlcNAc 2 , GlcNAc 2 Man 3 GlcNAc 2 , and GlcNAc 1 Man 4 GlcNAc 2 .  
     
     
         12 . A transgenic plant cell according to  claim 8  wherein said enzyme is localized within an intracellular organelle.  
     
     
         13 . A whole transgenic plant regenerated from the plant cell of  claim 8  wherein said plant comprises said nucleic acid sequence encoding an enzyme capable of performing a transfer reaction of a galactose residue to a non-reducing terminal acetylglucosamine.  
     
     
         14 . A transgenic seed produced by the plant of  claim 13  wherein said seed comprises said nucleic acid sequence encoding an enzyme capable of performing a transfer reaction of a galactose residue to a non-reducing terminal acetylglucosamine.