Suppression of tla1 gene expression for improved photosynthetic productivity

Abstract

The invention provides method and compositions to minimize the chlorophyll antenna size of photosynthesis by decreasing TLA1 gene expression, thereby improving solar conversion efficiencies and photosynthetic productivity in plants, e.g., green microalgae, under bright sunlight conditions.

What is claimed is: 
     
         1 . A method of decreasing chlorophyll antenna size in a plant, the method comprising:
 inhibiting expression of a Tla1 nucleic acid in a plant by introducing into the plant an expression cassette comprising a promoter operably linked to a polynucleotide, or a complement thereof, that specifically hybridizes to a nucleic acid that is at least 70% identical to at least 200 contiguous nucleotides of the Tla1 nucleic acid; and   selecting a plant with decreased chlorophyll antenna size compared to a plant in which the expression cassette has not been introduced.   
     
     
         2 . The method of  claim 1 , wherein the promoter is constitutive. 
     
     
         3 . The method of  claim 1 , wherein the promoter is inducible. 
     
     
         4 . The method of  claim 1 , wherein the polynucleotide is operably linked to the promoter in the antisense orientation. 
     
     
         5 . The method of  claim 1 , wherein the polynucleotide is operably linked to the promoter in the sense orientation. 
     
     
         6 . The method of  claim 1 , wherein the plant is green algae. 
     
     
         7 . A plant comprising an expression cassette comprising a polynucleotide, or a complement thereof, that specifically hybridizes to a nucleic acid that is at least 70% highest percent identity to at least 200 contiguous nucleotides of a Tla1 nucleic acid. 
     
     
         8 . The plant of  claim 7 , wherein the plant is green algae. 
     
     
         9 . A method of enhancing yields of photosynthetic productivity under high-density growth conditions, the method comprising cultivating a plant of  claim 7  under bright sunlight and high density growth conditions. 
     
     
         10 . A method of enhancing production of a compound of interest, the method comprising suppressing Tla1 gene expression in a plant; and cultivating the plant under conditions in which the compound is produced. 
     
     
         11 . The method of  claim 10 , wherein the plant is green algae. 
     
     
         12 . The method of  claim 11 , wherein the compound is H 2 , biodiesel, Beta-carotene, lutein, zeaxanthin, or astaxanthinproduction production, the method comprising suppressing Tla1 gene expression in a plante to be used for H 2  production; and cultivating the plant under conditions in which H 2  is produced.