The uptake and accumulation of polycyclic aromatic hydrocarbons (PAHs) in crops have gained much attention due to their toxicity to humans. Nitrogen (N) is an essential element for plant growth and has also been implicated in the acquisition and acropetal translocation of PAHs. OsNRT2.3b encodes a nitrate (NO₃⁻) transporter that is involved in the acquisition and mobilization of N in rice. Here, we investigated whether overexpression of OsNRT2.3b would exert any mitigating influence on the uptake and translocation of phenanthrene (Phe, a model PAH) in transgenic rice (Oryza sativa). The wild-type seedlings exhibited a reduction in plant height, primary root length, and shoot biomass when grown hydroponically in a medium supplemented with Phe. Acquisition of Phe by the roots and its subsequent translocation to shoots increased concomitantly with an increase in Phe concentration in the medium and duration of the treatment. OsNRT2.3b-overexpressing lines (Ox-6 and Ox-8) were generated independently. Compared with the wild-type, the concentration of Phe in Ox-6 and Ox-8 were significantly lower in the roots (47%- 54%) and shoots (22%–31%) grown hydroponically with Phe (1 mg/L). Further, the wild-type and Ox lines were grown to maturity in a pot soil under Phe conditions and the concentrations of Phe and total N were assayed in the culms and flag leaves. Compared with the wild-type, in Ox lines the concentration of total N significantly increased in the culms (288%–366%) and flag leaves (12%–25%), while that of Phe significantly reduced in the culms (25%–28%) and flag leaves (18%–21%). The results revealed an antagonistic correlation between the concentration of total N and Phe. The concentration of Phe was also significantly lower (29%–38%) in the seeds of Ox lines than the wild-type. The study highlighted the efficacy of overexpressing OsNRT2.3b in mitigating the Phe toxicity by attenuating its acquisition, mobilization, and allocation to the seeds.

作物中多环芳烃（PAHs）的吸收和积累因其对人体的毒性而倍受关注。氮（N）是植物生长的必要元素，也与PAH的获取和顶位易位有关。OsNRT2。图3b编码硝酸盐（NO ₃ ^- ），其参与在N水稻采集和动员转运蛋白。在这里，我们调查了OsNRT2是否过度表达。3b将对转基因水稻（水稻）中菲（Phe，PAH模型）的吸收和转运产生任何缓解影响。）。当在添加了Phe的培养基中进行水培生长时，野生型幼苗的株高，初生根长和苗生物量均降低。根部对苯丙氨酸的获取及其随后向芽的易位随培养基中和处理时间中苯丙氨酸浓度的增加而增加。OsNRT2。3b-过表达系（Ox-6和Ox-8）是独立产生的。与野生型相比，通过Phe（1 mg / L）进行水培生长的根部（47％-54％）和新芽（22％–31％）的Ox-6和Ox-8中的Phe浓度显着降低）。此外，野生型和Ox系在Phe条件下在盆栽土壤中生长至成熟，并在茎和旗叶中测定了Phe和总氮的浓度。与野生型相比，Ox系中茎中总氮的浓度显着增加（288％–366％）和旗叶（12％–25％），而Phe中的总N浓度显着降低（25％） –28％）和旗叶（18％–21％）。结果表明，总氮和苯丙氨酸之间存在拮抗作用。Ox系种子中的Phe浓度也显着低于野生型（29％–38％）。该研究强调了过表达的功效OsNRT2。图3b通过减弱其获取，动员和分配给种子来减轻Phe毒性。