Genetically modified plants having modulated flower development

Abstract

The present invention provides a genetically modified plant and a method for producing such a plant characterized as having modulated flower meristem development. As an illustrative example, the invention provides genetically modified tobacco and aspen plants characterized as having early floral meristem development and comprising a structural gene encoding the LEAFY protein in its genome.

We claim:  
     
         1 . A genetically modified plant, wherein its genome comprises a heterologous nucleotide sequence operably associated with a regulatory region, wherein the heterologous nucleotide sequence comprises: 
 a nucleotide sequence encoding a LEAFY protein of Arabidopsis (SEQ ID NO: 2) or a nucleotide sequence capable of hybridization under highly stringent conditions to the nucleic acid sequence of SEQ ID NO: 1; and 
 (i) a nucleic acid encoding an APETALA1 protein of Arabidopsis (SEQ ID NO: 4), or  
 (ii) a nucleic acid capable of hybridization under highly stringent conditions to a nucleic acid comprising the sequence of SEQ ID NO: 3, or  
 (iii) a nucleic acid encoding a FLORICAULA protein (SEQ ID NO: 6) from  Antirrhinum majus,  or  
 (iv) a nucleic acid capable of hybridization under highly stringent conditions to a nucleic acid comprising the sequence of SEQ ID NO: 5, or  
 (iii) a nucleic acid encoding a SQUAMOSA protein (SEQ ID NO:8) from  Antirrhinum majus,  or  
 (iv) a nucleic acid capable of hybridization under highly stringent conditions to SEQ ID NO: 7, or  
 (v) a combination of said nucleic acids,  
   wherein the genetically modified plant undergoes flower development at a time point earlier than that of a corresponding wildtype plant.    
     
     
         2 . The genetically modified plant of  claim 1 , wherein the regulatory region comprises a promoter.  
     
     
         3 . The genetically modified plant of  claim 2 , wherein the promoter is a constitutive promoter.  
     
     
         4 . The genetically modified plant of  claim 2 , wherein the promoter is an inducible promoter.  
     
     
         5 . The genetically modified plant of  claim 1 , wherein the heterologous nucleotide sequence further comprises a selectable marker.  
     
     
         6 . The genetically modified plant of  claim 1 , wherein the plant is a dicotyledonous plant.  
     
     
         7 . The genetically modified plant of  claim 1 , wherein the plant is a monocotyledonous plant.  
     
     
         8 . A plant cell derived from the plant of  claim 1 .  
     
     
         9 . Plant tissue derived from the plant of  claim 1 .  
     
     
         10 . A seed which germinates into a plant comprising a heterologous nucleic acid sequence operably associated with a regulatory region, wherein the heterologous nucleic acid sequence comprises: 
 a nucleotide sequence encoding a LEAFY protein of Arabidopsis (SEQ ID NO: 2) or a nucleotide sequence capable of hybridization under highly stringent conditions to a nucleic acid comprising the sequence of SEQ ID NO: 1; and 
 (i) a nucleic acid encoding an APETALA1 protein of Arabidopsis (SEQ ID NO: 4), or  
 (ii) a nucleic acid capable of hybridization under highly stringent conditions to a nucleic acid comprising the sequence of SEQ ID NO: 3, or  
 (iii) a nucleic acid encoding a FLORICAULA protein (SEQ ID NO: 6) from  Antirrhinum majus,  or  
 (iv) a nucleic acid capable of hybridization under highly stringent conditions to a nucleic acid comprising the sequence of SEQ ID NO: 5, or  
 (vi) a nucleic acid encoding a SQUAMOSA protein (SEQ ID NO:8) from  Antirrhinum majus,  or  
 (vii) a nucleic acid capable of hybridization under highly stringent conditions to SEQ ID NO: 7, or  
 (viii) a combination of said nucleic acids,  
   wherein the genetically modified plant undergoes flower development at a time point earlier than that of a corresponding wildtype plant.    
     
     
         11 . A method of producing a genetically modified plant characterized as having early flower meristem development, said method comprising: 
 contacting a plant cell with a vector comprising a regulatory sequence operably associated with a nucleic acid sequence, wherein said nucleic acid sequence comprises: 
 a nucleotide sequence encoding a LEAFY protein of Arabidopsis (SEQ ID NO: 2) or a nucleotide sequence that is capable of hybridization under stringent conditions to a nucleic acid comprising the sequence of SEQ ID NO: 1; and 
 (v) a nucleic acid encoding an APETALA1 protein of Arabidopsis (SEQ ID NO: 4), or  
 (vi) a nucleic acid capable of hybridization under highly stringent conditions to a nucleic acid comprising the sequence of SEQ ID NO: 3, or  
 (vii) a nucleic acid encoding a FLORICAULA protein (SEQ ID NO: 6) from  Antirrhinum majus,  or  
 (viii) a nucleic acid capable of hybridization under highly stringent conditions to a nucleic acid comprising the sequence of SEQ ID NO: 5, or  
 (ix) a nucleic acid encoding a SQUAMOSA protein (SEQ ID NO:8) from  Antirrhinum majus,  or  
 (x) a nucleic acid capable of hybridization under highly stringent conditions to SEQ ID NO: 7, or  
 (xi) a combination of said nucleic acids,  
 
   producing a plant from said transformed plant cell; and    selecting a plant exhibiting said early flower meristem development.    
     
     
         12 . The method of  claim 11 , wherein the contacting is by physical means.  
     
     
         13 . The method of  claim 11 , wherein the contacting is by chemical means.  
     
     
         14 . The method of  claim 11 , wherein the plant cell is selected from the group consisting of protoplasts, gamete producing cells, and cells which regenerate into a whole plant.  
     
     
         15 . The method of  claim 11 , wherein the promoter is a constitutive promoter.  
     
     
         16 . The method of  claim 11 , wherein the promoter is an inducible promoter.  
     
     
         17 . A vector comprising: 
 a regulatory sequence operably associated with a nucleotide sequence encoding a LEAFY protein of Arabidopsis (SEQ ID NO: 2) or a nucleotide sequence capable of hybridization under stringent conditions to a nucleotide sequence comprising the sequence of SEQ ID NO: 1; and    a nucleotide sequence encoding a protein selected from the group consisting of: 
 (ix) a nucleic acid encoding an APETALA1 protein of Arabidopsis (SEQ ID NO: 4), or  
 (x) a nucleic acid capable of hybridization under highly stringent conditions to a nucleic acid comprising the sequence of SEQ ID NO: 3, or  
 (xi) a nucleic acid encoding a FLORICAULA protein (SEQ ID NO: 6) from  Antirrhinum majus,  or  
 (xii) a nucleic acid capable of hybridization under highly stringent conditions to a nucleic acid comprising the sequence of SEQ ID NO: 5, or  
 (xii) a nucleic acid encoding a SQUAMOSA protein (SEQ ID NO:8) from  Antirrhinum majus,  or  
 (xiii) a nucleic acid capable of hybridization under highly stringent conditions to SEQ ID NO: 7, or  
 (ix) a combination of said nucleic acids, wherein the genetically modified plant undergoes flower development at a time point earlier than that of a corresponding wildtype plant.  
   
     
     
         18 . The vector of  claim 17 , wherein the vector comprises a T-DNA derived vector.  
     
     
         19 . The vector of  claim 17 , wherein the regulatory sequence is a promoter.  
     
     
         20 . The vector of  claim 19 , wherein the promoter is a constitutive promoter.  
     
     
         21 . The vector of  claim 19 , wherein the promoter is an inducible promoter.