Methods and compositions to regulate plant transformation susceptibility

Abstract

A genetic screen for Arabidopsis mutants displaying a hyper-susceptible to Agrobacterium transformation (hat) phenotype was performed. The gene disrupted in the hat3 mutant encodes a putative myb-family transcription factor (MTF) that negatively regulates susceptibility to Agrobacterium -mediated transformation. Over-expression of an integrin-like protein results in plants that are hyper-susceptible to transformation. Manipulation of MTF, members of this protein family, and members of the integrin domain-like protein family for example At14a allows improved control of Agrobacterium transformation, including in crops.

1 . Functional orthologs in plants of a family of myb transcription factors designated MTF in  Arabidopsis,  wherein the factors negatively regulate plant transformation susceptibility. 
     
     
         2 . A myb transcription factor of  claim 1  wherein the MTF is designated At2g40970. 
     
     
         3 . The myb transcription factors of  claim 1  wherein the plant is selected from the group consisting of rice,  Brassica  species, wheat, maize, and soybean. 
     
     
         4 . A method to increase transformation susceptibility in a plant, the method comprising:
 (a) mutating or down-regulating expression of a myb transcription factor gene in the plant; and   (b) contacting the plant with Agrobacteria to effect transformation.   
     
     
         5 . A method to increase transformation susceptibility in a plant, the method comprising:
 (a) overexpressing at least two genes in the plant, wherein the genes are upregulated in mtf mutants; and   (b) contacting the plant with Agrobacteria to effect transformation   
     
     
         6 . The method of  claim 5 , wherein two genes are At1g50060 and At5g15725. 
     
     
         7 . A method to increase transformation susceptibility in a plant, the method comprising:
 (a) decreasing expression of genes encoding the functional orthologs of  claim 1  in the plant by an agent selected from the group consisting of RNAi, cytokinins, and TZS expressing bacteria; and   (b) contacting the plant with Agrobacteria to effect transformation.   
     
     
         8 . (canceled) 
     
     
         9 . The method of  claim 4 , wherein the plant is a crop plant. 
     
     
         10 . The method of  claim 9  wherein the crop plant is selected from the group consisting of rice,  Brassica  species, wheat, maize, and soybean. 
     
     
         11 . A mutant plant with increased susceptibility to  Agrobacterium -mediated transformation, the mutant having the hat3 phenotype and a myb transcripted factor designated MTF or a functional ortholog of  claim 1 . 
     
     
         12 . A method to manipulate Agrobacterial transformation in a plant, the method comprising myb transcription factors according to  claim 1  and an integrin-like protein, in combination, to achieve a desired effect, wherein the effect comprises increased transformation susceptibility. 
     
     
         13 . The method of  claim 12  wherein the integrin-like protein is from a group designated At14a. 
     
     
         14 . (canceled) 
     
     
         15 . The myb transcription factors of  claim 12  selected from the group consisting of At2g40970 in  Arabidopsis  and functional orthologs from other plant species.