Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Overexpressing the ANR1 MADS-Box Gene in Transgenic Plants Provides New Insights into its Role in the Nitrate Regulation of Root Development
AU - Gan, Yinbo
AU - Bernreiter, Andreas
AU - Filleur, Sophie
AU - Abram, Beverley
AU - Forde, Brian G
PY - 2012/6
Y1 - 2012/6
N2 - The expression of the ANR1 MADS-box gene was manipulated in transgenic plants to investigate its role in the NO(3)(-)-dependent regulation of root development in Arabidopsis thaliana. Constitutive overexpression of ANR1 in roots, achieved using GAL4 enhancer trap lines, resulted in more rapid early seedling development, increased lengths and numbers of lateral roots and increased shoot fresh weight. Based on results obtained with five different enhancer trap lines, the overexpression of ANR1 in the lateral root tips appears to be more important for this phenotype than its level of expression in the developing lateral root primordia. Dexamethasone-mediated induction of ANR1 in lines expressing an ANR1-GR (glucocorticoid receptor) fusion protein stimulated lateral root growth but not primary root growth. Short-term (24 h) dexamethasone treatments led to prolonged stimulation of lateral root growth, whether the lateral roots were already mature or still unemerged at the time of treatment. In split-root experiments, localized application of dexamethasone to half of the root system of an ANR1-GR line elicited a localized increase in both the length and numbers of lateral roots, mimicking the effect of a localized NO(3)(-) treatment. In both types of transgenic line, the root phenotype was strongly dependent on the presence of NO(3)(-), indicating that there are additional components involved in ANR1 function that are NO(3)(-) regulated. The implications of these results for our understanding of ANR1's mode of action in the root response to localized NO(3)(-) are discussed.
AB - The expression of the ANR1 MADS-box gene was manipulated in transgenic plants to investigate its role in the NO(3)(-)-dependent regulation of root development in Arabidopsis thaliana. Constitutive overexpression of ANR1 in roots, achieved using GAL4 enhancer trap lines, resulted in more rapid early seedling development, increased lengths and numbers of lateral roots and increased shoot fresh weight. Based on results obtained with five different enhancer trap lines, the overexpression of ANR1 in the lateral root tips appears to be more important for this phenotype than its level of expression in the developing lateral root primordia. Dexamethasone-mediated induction of ANR1 in lines expressing an ANR1-GR (glucocorticoid receptor) fusion protein stimulated lateral root growth but not primary root growth. Short-term (24 h) dexamethasone treatments led to prolonged stimulation of lateral root growth, whether the lateral roots were already mature or still unemerged at the time of treatment. In split-root experiments, localized application of dexamethasone to half of the root system of an ANR1-GR line elicited a localized increase in both the length and numbers of lateral roots, mimicking the effect of a localized NO(3)(-) treatment. In both types of transgenic line, the root phenotype was strongly dependent on the presence of NO(3)(-), indicating that there are additional components involved in ANR1 function that are NO(3)(-) regulated. The implications of these results for our understanding of ANR1's mode of action in the root response to localized NO(3)(-) are discussed.
KW - Foraging
KW - Nitrate signaling
KW - Root architecture
KW - Root behavior
KW - Root development
KW - Transgenic plants
UR - http://www.scopus.com/inward/record.url?scp=84862179419&partnerID=8YFLogxK
U2 - 10.1093/pcp/pcs050
DO - 10.1093/pcp/pcs050
M3 - Journal article
C2 - 22523192
VL - 53
SP - 1003
EP - 1016
JO - Plant & cell physiology
JF - Plant & cell physiology
SN - 1471-9053
IS - 6
ER -