Abstract：
Although the interaction between P and Zn has long been recognized in plants, the physiological and molecular mechanisms underlying P and Zn interactions are poorly understood. We show here that P supply decreases the Zn concentration in maize shoots and roots. Compared to +P + Zn (addition of both P and Zn), +P-Zn reduced and -P-Zn increased the total length of 1° lateral roots (LRs). Under +P + Zn, both P and Zn concentrations were lower in the sl1 mutant roots than in wild-type (WT) maize roots, and P accumulation did not reduce the Zn concentration in ll1 mutant roots. Transcriptome profiling showed that the auxin signaling pathway contributed to P-mediated Zn homeostasis in maize. Auxin production and distribution were altered by changes in P and Zn supply. Cytosolic Zn co-localized with auxin accumulation under +P + Zn. Exogenous application of 1-NAA and L-Kyn altered the P-mediated root system architecture (RSA) under Zn deficiency. -P-Zn repressed the expression of miR167. Overexpression of ZmMIR167b increased the lengths of 1° LRs and the concentrations of P and Zn in maize. These results indicate that auxin-dependent RSA is important for P-mediated Zn homeostasis in maize.HighlightAuxin-dependent RSA is important for P-mediated Zn homeostasis in maize.
摘要：
虽然磷和锌之间的相互作用早已在植物中得到认可，P和Zn相互作用的生理和分子机制知之甚少。我们在这里表明，磷的供应降低了玉米芽和根中的锌浓度。与+P+Zn(同时添加P和Zn)相比，+P-Zn减少，-P-Zn增加1°侧根（LRs）的总长度。在+P+Zn下，SL1突变体根中的P和Zn浓度均低于野生型（WT）玉米根，磷的积累并没有降低ll1突变体根中的Zn浓度。转录组分析表明，生长素信号通路有助于玉米中P介导的Zn稳态。生长素的产生和分布因磷和锌供应的变化而改变。在+P+Zn下，胞质Zn与生长素积累共定位。1-NAA和L-Kyn的外源应用改变了锌缺乏下P介导的根系结构（RSA）。-P-Zn抑制miR167的表达。ZmMIR167b的过表达增加了玉米中1°LR的长度以及P和Zn的浓度。这些结果表明，生长素依赖性RSA对玉米中P介导的Zn稳态很重要。强调生长素依赖性RSA对玉米中P介导的Zn稳态很重要。
