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.

1 . A method of enhancing H 2  production, the method comprising suppressing Tla1 gene expression in an algae to be used for H 2  production; and cultivating the algae under conditions in which H 2  is produced. 
     
     
         2 . The method of  claim 1 , wherein the algae is  Chlamydomonas reinhardtii, Scenedesmus obliquus , or  Chlorella vulgaris.    
     
     
         3 . A method of enhancing bio-oil or bio-diesel production, the method comprising suppressing Tla1 gene expression in an algae to be used for bio-oil or bio-diesel production; and cultivating the algae under conditions in which bio-oil or bio-diesel is produced. 
     
     
         4 . The method of  claim 3 , wherein the algae is  Botryococcus braunii  or  Botryococcus sudeticus.    
     
     
         5 . A method of enhancing Beta-carotene, lutein or zeaxanthin production, the method comprising suppressing Tla1 gene expression in an algae to be used for Beta-carotene, lutein or zeaxanthin production; and cultivating the algae under conditions in which Beta-carotene, lutein or zeaxanthin is produced. 
     
     
         6 . The method of  claim 5 , wherein the algae is  Dunaliella salina.    
     
     
         7 . A method of enhancing astaxanthin production, the method comprising suppressing Tla1 gene expression in an algae to be used for astaxanthin production; and cultivating the algae under conditions in which astaxanthin is produced. 
     
     
         8 . The method of  claim 7 , wherein the algae is  Haematococcus pluvialis.    
     
     
         9 . A method of screening for green algae that show enhanced yield of photosynthetic productivity under high-density growth conditions, the method comprising:
 introducing mutations into a population of green algae; and   screening the green algae for inhibition of Tla1 gene expression, wherein inhibition of Tla1 gene expression is determined by measuring the level of Tla1 mRNA or Tla1 protein.   
     
     
         10 . The method of  claim 9 , wherein inhibition of Tla1 gene expression is determined by measuring the level of Tla1 protein. 
     
     
         11 . The method of  claim 9 , wherein the algae are selected from  Chlamydomonas reinhardtii, Scenedesmus obliquus, Chlorella vulgaris, Botryococcus braunii, Botryococcus sudeticus, Dunaliella salina , or  Haematococcus pluvialis.