Nitrogen uptake in plants

Abstract

This disclosure provides transgenic plants, including crop plants and methods for their production. The transgenic plants comprise recombinant DNA constructs for the expression of polypeptides encoded by the DNA constructs. The polypeptides are capable of conferring improved traits to the transgenic plants when expressed under the control of a tissue-enhanced promoter. This disclosure also pertains to transgenic plants and their progeny plants, wherein the transgenic or progeny plants comprise the recombinant DNA constructs and are selected for having enhanced nitrogen use efficiency and/or nitrogen uptake. Seed of the transgenic plants that can be grown into a plant that comprise the disclosed recombinant DNA constructs and exhibits having enhanced nitrogen use efficiency, and which may be selected for this trait, are also envisioned.

What is claimed is: 
     
       1. A method of altering architecture or physiology of a green tissue in a plant, comprising:
 (a) introducing into a plant cell a nucleic acid construct comprising a tissue-enhanced promoter consisting of the nucleic acid sequence set forth in SEQ ID NO:2324, that preferentially regulates expression of a polypeptide having the amino acid sequence set forth in SEQ ID NO:2244 in a green tissue, 
 wherein regulation of expression of the polypeptide increases nitrogen uptake, assimilation, nitrogen uptake efficiency (NUpE), nitrogen usage index (UI), and/or seed yield in a transgenic plant comprising the plant cell as compared to a control or reference plant that does not comprise the nucleic acid construct; and 
 (b) optionally, identifying the transgenic plant comprising the plant cell. 
 
     
     
       2. A method for producing a plant that has enhanced nitrogen uptake, assimilation, nitrogen uptake efficiency (NUpE), nitrogen usage index (UI), and/or seed yield, the method comprising:
 (a) providing a plant with a nucleic acid construct comprising a tissue-enhanced promoter consisting of the nucleic acid sequence set forth in SEQ ID NO:2324, that preferentially regulates expression of a polypeptide having the amino acid sequence set forth in SEQ ID NO:2244 in a green tissue, 
 wherein regulation of expression of the polypeptide increases nitrogen uptake in a transgenic plant comprising the plant cell as compared to a control or reference plant that does not comprise the nucleic acid construct; and 
 (b) optionally, identifying the transgenic plant comprising the plant cell. 
 
     
     
       3. The method of  claim 2 , wherein the providing a plant with a nucleic acid construct comprises transforming the plant with the nucleic acid construct. 
     
     
       4. The method of  claim 2 , wherein the providing a plant with a nucleic acid construct comprises crossing the plant with a second plant that comprises the nucleic acid construct.