Matrices for over represented motifs were compared to existing TF bind ing motifs in JASPAR and TRANSFAC using STAMP. Comparison with Microarray Gene Expression Results from the ChIP chip and DRE analysis were inte grated with whole genome gene expression profiling data from mice orally gavaged with 30 ug kg TCDD using 4 × 44 k whole genome oligonucleotide arrays from Agilent Technologies. The genomic loca tions of the differentially responsive genes 0. 999 were obtained for each RefSeq sequence associated with the gene from the refGene database in the UCSC DHFR inhibitor Genome Browser. Circos plots were generated to visualize the locations of DRE cores,  regions of AhR enrichment and temporal heat maps of temporal gene expression responses. The genus Amaranthus L. comprises C4 dicotyledonous herbaceous plants classified into approximately 70 species. It has a worldwide distribution, although most species are found in the warm temperate and tropical regions of the world. Many amaranth species are cultivated as ornamentals or a source of highly nutritious pseudocereals and vegetables, others, are notoriously aggressive weeds that affect many agricultural areas of the world. The grain amaranths are ancestral crops native to the New World. They are classified along with their putative progenitor species in what is known as the A. hybridus complex. Restricted for cen turies to a limited cultivation in Meso America as a result of religious intolerance, grain amaranths have gradually acquired renewed interest due to their various nutritional and health related traits, in addition to their highly desirable agronomic characteristics. These charac teristics offer a viable alternative to cereals and other crops in many stressful agricultural settings, particularly those where soil moisture conditions vary considerably between growing seasons. The increased ability to withstand drought stress that characterizes grain amaranth is closely related to its superior water use efficiency, variously defined as the ratio of economic yield to evapo transpiration or of the amount CO2 assimilated to water loss. WUE in grain amaranth has been found to be higher than in other C3 and C4 crops, includ ing wheat, corn, cotton and sorghum. Moreover, the high salt tolerance of grain amaranth has also been asso ciated with a high WUE. The drought tolerance of grain amaranth has been attributed to the inherently stress attenuating physiology of the C4 pathway, an inde terminate flowering habit and the capacity to grow long taproots and develop an extensive lateral root system in response to water shortage in the soil.