Method for producing polyisoprenoid, transformed plant, method for producing pneumatic tire and method for producing rubber product

Abstract

Provided is a method for producing a polyisoprenoid, which can increase natural rubber production by enhancing the rubber synthesis activity of rubber particles. The present invention provides methods for producing a polyisoprenoid using a gene coding for a cis-prenyltransferase (CPT) family protein, a gene coding for a Nogo-B receptor (NgBR) family protein and a gene coding for a rubber elongation factor (REF) family protein, specifically a method for producing a polyisoprenoid in vitro using rubber particles bound to proteins coded for by these genes, and a method for producing a polyisoprenoid in vivo using a recombinant organism (plant) having these genes introduced therein.

The invention claimed is: 
     
       1. A method of producing a rubber, the method comprising:
 a step of binding a protein expressed by a gene coding for a cis-prenyltransferase (CPT) family protein, a protein expressed by a gene coding for a Nogo-B receptor (NgBR) family protein, and a protein expressed by a gene coding for a rubber elongation factor (REF) family protein to rubber particles in vitro, 
 wherein the gene coding a for a cis-prenyltransferase (CPT) family protein, the gene coding for a Nogo-B receptor (NgBR) family protein, and the gene coding for a rubber elongation factor (REF) family protein are each derived from plants, and 
 wherein the cis-prenyltransferase (CPT) family protein is at least one selected from the group consisting of CPT from  Hevea brasiliensis  (HRT1, HRT2, CPT3-5), AtCPTl-9 from  Arabidopsis thaliana , CPT 1-3 from lettuce, and CPT 1-3 from  Taraxacum kok - saghyz , and wherein the Nogo-B receptor (NgBR) family protein is at least one selected from the group consisting of NgBR from  Hevea brasiliensis  (HRTBP), LEW1 from  Arabidopsis thaliana , LsCPTLl-2 from lettuce, and TbRTA from  Taraxacum , and 
 wherein the rubber elongation factor (REF) family protein is REF from  Hevea brasiliensis.    
 
     
     
       2. The method for producing a rubber according to  claim 1 ,
 wherein the binding step comprises performing protein synthesis in the presence of both rubber particles and a cell-free protein synthesis solution containing an mRNA coding for a cis-prenyltransferase (CPT) family protein, an mRNA coding for a Nogo-B receptor (NgBR) family protein, and an mRNA coding for a rubber elongation factor (REF) family protein to bind the CPT family protein, the NgBR family protein, and the REF family protein to the rubber particles. 
 
     
     
       3. The method for producing a rubber according to  claim 2 ,
 wherein the cell-free protein synthesis solution contains a germ extract. 
 
     
     
       4. The method for producing a rubber according to  claim 3 ,
 wherein the germ extract is derived from wheat. 
 
     
     
       5. The method for producing a rubber according to  claim 2 ,
 wherein the rubber particles are present in the cell-free protein synthesis solution at a concentration of 5 to 50 g/L. 
 
     
     
       6. The method for producing a rubber according to  claim 2 ,
 wherein each gene of the gene coding for a cis-prenyltransferase (CPT) family protein, the gene coding for a Nogo-B receptor (NgBR) family protein, and the gene coding for a rubber elongation factor (REF) family protein, is derived from  Hevea brasiliensis.