Abstract: Nitrate is the main form of nitrogen absorbed in land plants, and its absorption is highly correlated with function of nitrate transporters (NRT1). Sorghum bicolor is tolerant to nutrient deficiency, and soil nitrogen absorption and utilization efficiency is high. Based on the NRT1 of Arabidopsis thaliana and Oryza sativa, the full length sequence of the SbNRT1 gene was obtained by screening the sorghum nucleic acid and protein database through Blast, and 20 SbNRT1 genes were identified in combination with bioinformatics methods, gene structure analysis, phylogenetic tree analysis, gene expression, selective evolution and protein physicochemical properties, secondary and tertiary structure of SbNRT1 gene family. The results showed that SbNRT1 gene families were distributed on SBI-01～SBI-10, with exception of SBI-08; SbNRT1 proteins are hydrophobic proteins, most of them have no signal peptides, and subcellular localization is mostly on the plasma membrane; the secondary structure is dominated by α-helix and random coils. The SbNRT1 protein family tertiary structure is consistent with predictions, credibility reached 93 percent. SbNRT1 protein family were divided into eight branches. Members of SbNRT1 are more closely related to those of foxtail millet and maize, and appeared in the evolution of single and double cotyledons differentiation. Sobic.004G193000 gene is expressed at a high level in many parts of the growth period. Expression of Sobic.001G133900, Sobic.003G295500 and Sobic.001G302800 are induced in the roots by nitrate and ammonium and urea. ka/ks value calculated based on data for genome resequence for sorghum accession indicated that the evolution of SbNRT1 has purification effect. The results of this study provide a basis for further research on the function of genes related to nitrogen use efficiency in sorghum.
Key words: sorghum (Sorghum bicolor); NRT1; gene expression; systematic evolutionary analysis; DNA variation
（Acta Laser Biology Sinica, 2021, 30(5): 459-467）