Methods of affecting nitrogen assimilation in plants

Abstract

Provided herein are compositions and methods for producing transgenic plants. In specific embodiments, transgenic plants comprise a construct comprising a polynucleotide encoding CCA1, GLK1 or bZIP1, operably linked to a plant-specific promote, wherein the CCA1, GLK1 or bZIP1 is ectopically overexpressed in the transgenic plants, and wherein the promoter is optionally a constitutive or inducible promoter. In other embodiments, transgenic plants in which express a lower level of CCA1, GLK1 or bZIP1 are provided. Also provided herein are commercial products (e.g., pulp, paper, paper products, or lumber) derived from the transgenic plants (e.g., transgenic trees) produced using the methods provided herein.

1 . A method for improving nitrogen assimilation and usage in a plant in which more nitrogen is available for biosynthesis, said method comprising fa) overexpressing GLK1 in the plant or (b) underexpressing bZIP1 in the plant or (c) overexpressing GLK1 and underexpressing bZIP1 in the plant. 
     
     
         2 .- 11 . (canceled) 
     
     
         12 . A method for altering nitrogen accumulation and storage in a plant, said method comprising (a) overexpressing bZIP1 in the plant or (b) underexpressing CCA1 in the plant or (c) overexpressing bZIP1 in the plant and underexpressing GLK1 in the plant. 
     
     
         13 .- 20 . (canceled) 
     
     
         21 . A transgenic plant comprising
 (i) a polynucleotide encoding GLK1 operatively linked to a promoter with activity in plants, wherein the promoter is optionally (a) a constitutive or inducible promoter or (b) associated with a constitutive or inducible regulatory element .  or   (ii) a polynucleotide encoding GLK1 operatively linked to a promoter with activity in plants and comprising a polynucleotide encoding CCA1 operatively linked to a second promoter with activity in plants, wherein the first and second promoter are optionally (a) a constitutive or inducible promoter or (b) associated with an constitutive or inducible regulatory element, and wherein the first and second promoter can be the same or different or   (iii) a mutation in the coding sequence of bZIP1 or a mutation in the transcriptional or translational control sequences of bZIP1, such that the levels of bZIP1 produced in the plant are less compared to a non-transgenic control plant or   (iv) a polynucleotide encoding bZIP1 operatively linked to a promoter with activity in plants, wherein the promoter is optionally (a) a constitutive or inducible promoter or (b) associated with a constitutive or inducible regulatory element or   (v) a mutation in the coding sequence of CCA1 or a mutation in the transcriptional or translational control sequences of CCA1, such that the levels of CCA1 produced in the plant are less compared to a non-transgenic control plant or   (vi) a polynucleotide encoding bZIP1 operatively linked to a promoter with activity in plants and comprising a mutation in the coding sequence of CCA1 or a mutation in the transcriptional or translational control sequences of CCA1, such that the levels of CCA1 produced in the plant are less compared to a non-transgenic control plant, wherein the promoter is optionally (a) a constitutive or inducible promoter or (b) associated with an constitutive or inducible regulatory element.   
     
     
         22 .- 47 . (canceled) 
     
     
         48 . A transgenic plant that exhibits increased nitrogen-assimilation capacity, increased nitrogen storage capacity, or both, as compared to a wild-type plant, the transgenic plant comprising a first gene construct comprising a polynucleotide encoding Basic Leucine Zipper 1 (bZIP1) operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding Myb Domain Protein 73 (MYB73) operatively linked to a second promoter with activity in plants, a third gene construct comprising a polynucleotide encoding Circadian Clock Associated 1 (CCA1) operatively linked to a third promoter with activity in plants, a fourth gene construct comprising a polynucleotide encoding Golden 2-like 1 (GLK1) operatively linked to a fourth promoter with activity in plants, a fifth gene construct comprising a polynucleotide encoding C3HC4 RING-type Zinc Finger (C3HC4) operatively linked to a fifth promoter with activity in plants, and a sixth gene construct comprising a polynucleotide encoding Basic Leucine Zipper 9 (bZIP9) operatively linked to a sixth promoter with activity in plants, wherein the first, second, third, fourth, fifth, and sixth promoters are optionally (a) a constitutive, tissue-specific, or inducible promoter or (b) associated with a constitutive or inducible regulatory element, and wherein the first, second, third, fourth, fifth, and sixth promoters can be the same or different. 
     
     
         49 . A transgenic plant that exhibits increased nitrogen-assimilation capacity as compared to a wild-type plant, the transgenic plant comprising
 (i) a first gene construct comprising a polynucleotide encoding CCA 1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding GLK1 operatively linked to a second promoter with activity in plants, a third gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a third promoter with activity in plants, and a fourth gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a fourth promoter with activity in plants, wherein the first, second, third, and fourth promoters are optionally (a) a constitutive, tissue-specific, or inducible promoter or (b) associated with a constitutive or inducible regulatory element, and wherein the first, second, third, and fourth promoters can be the same or different; or   (ii) a first gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a first promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, and a second gene construct comprising a polynucleotide encoding a mutant form of MYB73 operatively linked to a second promoter with activity in plants, wherein the mutant form of MYB73 results in decreased expression of MYB73, wherein the first and second promoters are optionally (a) a constitutive, tissue-specific, or inducible promoter or (b) associated with a constitutive or inducible regulatory element, and wherein the first and second promoters can be the same or different; or   (iii)
 (A) a first gene construct comprising a polynucleotide encoding CCA 1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding GLK1 operatively linked to a second promoter with activity in plants, or 
 (B) a first gene construct comprising a polynucleotide encoding CCA 1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a second promoter with activity in plants, or 
 (C) a first gene construct comprising a polynucleotide encoding CCA 1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a second promoter with activity in plants, or 
 (D) a first gene construct comprising a polynucleotide encoding GLK 1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a second promoter with activity in plants, or 
 (E) a first gene construct comprising a polynucleotide encoding GLK 1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a second promoter with activity in plants, or 
 (F) a first gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a second promoter with activity in plants, 
   wherein the first and second promoters are optionally (a) a constitutive, tissue-specific, or inducible promoter or (b) associated with a constitutive or inducible regulatory element, and wherein the first and second promoters can be the same or different; or   (iv)
 (A) a first gene construct comprising a polynucleotide encoding CCA 1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of MYB73 operatively linked to a second promoter with activity in plants, wherein the mutant form of MYB73 results in decreased expression of MYB73 , or 
 (B) a first gene construct comprising a polynucleotide encoding CCA 1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, or 
 (C) a first gene construct comprising a polynucleotide encoding GLK1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form ofMYB73 operatively linked to a second promoter with activity in plants, wherein the mutant form of MYB73 results in decreased expression ofMYB73, or 
 (D) a first gene construct comprising a polynucleotide encoding GLK1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, or 
 (E) a first gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form ofMYB73 operatively linked to a second promoter with activity in plants, wherein the mutant form of MYB73 results in decreased expression ofMYB73, or 
 (F) a first gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, or 
 (G) a first gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form ofMYB73 operatively linked to a second promoter with activity in plants, wherein the mutant form of MYB73 results in decreased expression ofMYB73, or 
 (H) a first gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, 
   
       wherein the first and second promoters are optionally (a) a constitutive, tissue-specific, or inducible promoter or (b) associated with a constitutive or inducible regulatory element, and wherein the first and second promoters can be the same or different; or
 (v)
 (A) a first gene construct comprising a polynucleotide encoding CCA1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding GLK1 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a third promoter with activity in plants, or 
 (B) a first gene construct comprising a polynucleotide encoding CCA1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding GLK1 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a third promoter with activity in plants, or 
 (C) a first gene construct comprising a polynucleotide encoding CCA1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a third promoter with activity in plants, or 
 (D) a first gene construct comprising a polynucleotide encoding GLK1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a third promoter with activity in plants, or 
 (E) a first gene construct comprising a polynucleotide encoding CCA1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding a mutant form of MYB73 operatively linked to a second promoter with activity in plants, wherein the mutant form of MYB73 results in decreased expression of MYB73, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, or 
 (F) a first gene construct comprising a polynucleotide encoding GLK1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding a mutant form of MYB73 operatively linked to a second promoter with activity in plants, wherein the mutant form of MYB73 results in decreased expression of MYB73, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, or 
 (G) a first gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding a mutant form of MYB73 operatively linked to a second promoter with activity in plants, wherein the mutant form of MYB73 results in decreased expression of MYB73, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, or 
 (H) a first gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding a mutant form of MYB73 operatively linked to a second promoter with activity in plants, wherein the mutant form of MYB73 results in decreased expression of MYB73, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, or 
 (I) a first gene construct comprising a polynucleotide encoding CCA 1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding GLK1 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding a mutant form of MYB73 operatively linked to a third promoter with activity in plants, wherein the mutant form ofMYB73 results in decreased expression ofMYB73, or 
 (J) a first gene construct comprising a polynucleotide encoding CCA 1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding a mutant form of MYB73 operatively linked to a third promoter with activity in plants, wherein the mutant form ofMYB73 results in decreased expression ofMYB73, or 
 (K) a first gene construct comprising a polynucleotide encoding CCA 1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding a mutant form of MYB73 operatively linked to a third promoter with activity in plants, wherein the mutant form ofMYB73 results in decreased expression ofMYB73, or 
 (L) a first gene construct comprising a polynucleotide encoding GLK1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding a mutant form of MYB73 operatively linked to a third promoter with activity in plants, wherein the mutant form ofMYB73 results in decreased expression ofMYB73, or 
 (M) a first gene construct comprising a polynucleotide encoding GLK1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding a mutant form of MYB73 operatively linked to a third promoter with activity in plants, wherein the mutant form ofMYB73 results in decreased expression ofMYB73, or 
 (N) a first gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding a mutant form of MYB73 operatively linked to a third promoter with activity in plants, wherein the mutant form ofMYB73 results in decreased expression ofMYB73, or 
 (O) a first gene construct comprising a polynucleotide encoding CCA 1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding GLK1 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP 1 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, or 
 (P) a first gene construct comprising a polynucleotide encoding CCA1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, or 
 (Q) a first gene construct comprising a polynucleotide encoding CCA1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, or 
 (R) a first gene construct comprising a polynucleotide encoding GLK1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, or 
 (S) a first gene construct comprising a polynucleotide encoding GLK1 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, or 
 (T) a first gene construct comprising a polynucleotide encoding C3HC4 operatively linked to a first promoter with activity in plants, a second gene construct comprising a polynucleotide encoding bZIP9 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP1 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP1 results in decreased expression of bZIP1, 
 
 wherein the first, second, and third promoters are optionally (a) a constitutive, tissue-specific, or inducible promoter or (b) associated with a constitutive or inducible regulatory element, and wherein the first, second and third promoters can be the same or different. 
 
     
     
         50 . A transgenic plant that exhibits increased nitrogen-storage capacity as compared to a wild-type plant, the transgenic plant comprising
 (i) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA1, a second gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a second promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, a third gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a third promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, and a fourth gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a fourth promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, wherein the first, second, third, and fourth promoters are optionally (a) a constitutive, tissue-specific, or inducible promoter or (b) associated with a constitutive or inducible regulatory element, and wherein the first, second, third, and fourth promoters can be the same or different; or   (ii) a first gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding MYB73 operatively linked to a second promoter with activity in plants, wherein the first and second promoters are optionally (a) a constitutive, tissue-specific, or inducible promoter or (b) associated with a constitutive or inducible regulatory element, and wherein the first and second promoters can be the same or different; or   (iii)
 (A) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA1, and a second gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a second promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, or 
 (B) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA1, and a second gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a second promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, or 
 (C) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA1, and a second gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, or 
 (D) a first gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a first promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, and a second gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a second promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, or 
 (E) a first gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a first promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, and a second gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, or 
 (F) a first gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a first promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, and a second gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, 
   wherein the first and second promoters are optionally (a) a constitutive, tissue-specific, or inducible promoter or (b) associated with a constitutive or inducible regulatory element, and wherein the first and second promoters can be the same or different; or   (iv)
 (A) a first gene construct comprising a polynucleotide encoding MYB73 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a second promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA1, or 
 (B) a first gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a second promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA 1, or 
 (C) a first gene construct comprising a polynucleotide encoding MYB73 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a second promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, or 
 (D) a first gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a second promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, or 
 (E) a first gene construct comprising a polynucleotide encoding MYB73 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a second promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, or 
 (F) a first gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a second promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, or 
 (G)a first gene construct comprising a polynucleotide encoding MYB73 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, or 
 (H) a first gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a first promoter with activity in plants, and a second gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, 
   
       wherein the first and second promoters are optionally (a) a constitutive, tissue-specific, or inducible promoter or (b) associated with a constitutive or inducible regulatory element, and wherein the first and second promoters can be the same or different; or
 (v)
 (A) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA1, a second gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a second promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, and a third gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a third promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, or 
 (B) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA1, a second gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a second promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, or 
 (C) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA1, a second gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a second promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, or 
 (D) a first gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a first promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, a second gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a second promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, and a third gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a third promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, or 
 (E) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA1, a second gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding MYB73 operatively linked to a third promoter with activity in plants, or 
 (F) a first gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a first promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, a second gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding MYB73 operatively linked to a third promoter with activity in plants, or 
 (G) a first gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a first promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, a second gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding MYB73 operatively linked to a third promoter with activity in plants, or 
 (H) a first gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a first promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, a second gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a second promoter with activity in plants, and a third gene construct comprising a polynucleotide encoding MYB73 operatively linked to a third promoter with activity in plants, or 
 (I) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA 1 results in decreased expression of CCA1, a second gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a second promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, and a third gene construct comprising a polynucleotide encoding MYB73 operatively linked to a third promoter with activity in plants, or 
 (J) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA 1, a second gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a second promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, and a third gene construct comprising a polynucleotide encoding MYB73 operatively linked to a third promoter with activity in plants, or 
 (K) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA 1, a second gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, and a third gene construct comprising a polynucleotide encoding MYB73 operatively linked to a third promoter with activity in plants, or 
 (L) a first gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a first promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, a second gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a second promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, and a third gene construct comprising a polynucleotide encoding MYB73 operatively linked to a third promoter with activity in plants, or 
 (M) a first gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a first promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, a second gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, and a third gene construct comprising a polynucleotide encoding MYB73 operatively linked to a third promoter with activity in plants, or 
 (N) a first gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a first promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, a second gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, and a third gene construct comprising a polynucleotide encoding MYB73 operatively linked to a third promoter with activity in plants, or 
 (O) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA1, a second gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a second promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, and a third gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a third promoter with activity in plants, or 
 (P) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA1, a second gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a second promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, and a third gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a third promoter with activity in plants, or 
 (Q) a first gene construct comprising a polynucleotide encoding a mutant form of CCA1 operatively linked to a first promoter with activity in plants, wherein the mutant form of CCA1 results in decreased expression of CCA1, a second gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, and a third gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a third promoter with activity in plants, or 
 (R) a first gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a first promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, a second gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a second promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, and a third gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a third promoter with activity in plants, or 
 (S) a first gene construct comprising a polynucleotide encoding a mutant form of GLK1 operatively linked to a first promoter with activity in plants, wherein the mutant form of GLK1 results in decreased expression of GLK1, a second gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, and a third gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a third promoter with activity in plants, or 
 (T) a first gene construct comprising a polynucleotide encoding a mutant form of C3HC4 operatively linked to a first promoter with activity in plants, wherein the mutant form of C3HC4 results in decreased expression of C3HC4, a second gene construct comprising a polynucleotide encoding a mutant form of bZIP9 operatively linked to a second promoter with activity in plants, wherein the mutant form of bZIP9 results in decreased expression of bZIP9, and a third gene construct comprising a polynucleotide encoding bZIP1 operatively linked to a third promoter with activity in plants, wherein the first, second, and third promoters are optionally (a) a constitutive, tissue-specific, or inducible promoter or (b) associated with a constitutive or inducible regulatory element, and wherein the first, second and third promoters can be the same or different. 
 
 
     
     
         51 . A transgenic plant that exhibits increased nitrogen-assimilation or increased nitrogen storage capacity, as compared to a wild-type plant, the transgenic plant comprising a gene construct comprising a polynucleotide encoding MYB73 or C3HC4 operatively linked to a promoter with activity in plants, wherein the promoter is optionally (a) a constitutive, tissue-specific, or inducible promoter or (b) associated with a constitutive or inducible regulatory element. 
     
     
         52 . The transgenic plant of  claim 48 , wherein bZIP 1,MYB73,CCA1,GLK1,C3HC4, and bZIP9 are ectopically overexpressed. 
     
     
         53 . The transgenic plant of  claim 48 , wherein the first and second promoters are seed-specific promoters and the third, fourth, fifth, and sixth promoters are leaf-specific promoters. 
     
     
         54 . The transgenic plant of  claim 48 , wherein the plant is a species of the genus Arabidopsis. 
     
     
         55 . The transgenic plant of  claim 48 , wherein the plant is a species of woody, ornamental, decorative, crop, cereal, fruit, or vegetable. 
     
     
         56 . The transgenic plant of  claim 48 , wherein the plant is a species of one of the following genuses:  Acorus, Aegilops, Allium, Amborella, Antirrhinum, Apium, Arachis, Beta, Betula, Brassica, Capsicum, Ceratopteris, Citrus, Cryptomeria, Cycas, Descurainia, Eschscholzia, Eucalyptus, Glycine, Gossypium, Hedyotis, Helianthus, Hordeum, Ipomoea, Lactuca, Linum, Liriodendron, Lotus, Lupinus, Lycopersicon, Medicago, Mesembryanthemum, Nicotiana, Nuphar, Pennisetum, Persea, Phaseolus, Physcomitrella, Picea, Pinus, Poncirus, Populus, Prunus, Robinia, Rosa, Saccharum, Schedonorus, Secale, Sesamum, Solanum, Sorghum, Stevia, Thellungiella, Theobroma, Triphysaria, Triticum, Vitis, Zea , or  Zinnia.    
     
     
         57 . A method of producing a plant-derived commercial product using the transgenic plant of  claim 48 , wherein optionally
 (a) said transgenic plant is a tree, and said commercial product is pulp, paper, a paper product, or lumber; or   (b) said transgenic plant is tobacco, and said commercial product is a cigarette, cigar, or chewing tobacco; or   (c) said transgenic plant is a crop, and said commercial product is a fruit or vegetable; or   (d) said transgenic plant is a grain, and said commercial product is bread, flour, cereal, oat meal, or rice.   
     
     
         58 . A method of producing a plant-derived commercial product using the transgenic plant of  claim 49 , wherein optionally
 (a) said transgenic plant is a tree, and said commercial product is pulp, paper, a paper product, or lumber; or   (b) said transgenic plant is tobacco, and said commercial product is a cigarette, cigar, or chewing tobacco; or   (c) said transgenic plant is a crop, and said commercial product is a fruit or vegetable; or   (d) said transgenic plant is a grain, and said commercial product is bread, flour, cereal, oat meal, or rice.   
     
     
         59 . A method of producing a plant-derived commercial product using the transgenic plant of  claim 50 , wherein optionally
 (a) said transgenic plant is a tree, and said commercial product is pulp, paper, a paper product, or lumber; or   (b) said transgenic plant is tobacco, and said commercial product is a cigarette, cigar, or chewing tobacco; or   (c) said transgenic plant is a crop, and said commercial product is a fruit or vegetable; or   (d) said transgenic plant is a grain, and said commercial product is bread, flour, cereal, oat meal, or rice.   
     
     
         60 . A method of producing a plant-derived commercial product using the transgenic plant of  claim 51 , wherein optionally
 (a) said transgenic plant is a tree, and said commercial product is pulp, paper, a paper product, or lumber; or   (b) said transgenic plant is tobacco, and said commercial product is a cigarette, cigar, or chewing tobacco; or   (c) said transgenic plant is a crop, and said commercial product is a fruit or vegetable; or   (d) said transgenic plant is a grain, and said commercial product is bread, flour, cereal, oat meal, or rice.