菊花(ChryranthemummorifoliumRamat。)是世界上最大的切花之一。磷酸盐转运蛋白Pht1家族成员CmPht1;2蛋白(CmPT2)在菊花应对低磷酸盐(LP)胁迫中起重要作用。翻译后修饰(PTM)可以多种方式调节蛋白质的功能。这里,我们使用酵母和水稻系统通过确定推定糖基化的关键氨基酸残基的突变效应来研究推定PTM在CmPT2中的作用,磷酸化,和肉豆蔻酰化位点。我们在推定的PTM位点中选择了9个氨基酸残基,并将它们突变为丙氨酸(A)(Cmphts)。CmPT2在LP条件下恢复酵母菌株MB192的生长。然而,G84A,G222A,T239A,Y242A,N422A突变体在LP条件下不能正常生长。磷吸收动力学分析表明,CmPT2的Km为65.7μM。在九个Cmphts中,在水稻中进一步评估了Km(124.4-397.5μM)大于CmPT2的五个表达。CmPT2-OE的过表达增加了株高,有效穗数,分支编号,和产量与野生型武云井号相比。7\'(W7)。与CmPT2-OE菌株相比,Cmphts-OE的过表达导致株高和有效穗数降低。在高(正常)磷酸盐(HP)和LP条件下,CmPT2-OE根中的Pi含量均高于W7。然而,在HP和LP条件下,N422A-OE菌株的叶片和根中的Pi含量均显着低于CmPT2-OE菌株。在LP条件下,CmPT2-OE中的磷饥饿反应(PSR)基因在转录水平上受到抑制。磷相关基因在T239A,Y242A,LP条件下的N422A-OE与CmPT2-OE不同。总之,CmPT2的这5个翻译后修饰残基在调节CmPT2的功能中起关键作用。这项工作促进了我们对磷酸盐转运蛋白功能的理解,并为提高作物中磷的利用效率提供了遗传资源。
Chrysanthemum (Chrysanthemum morifolium Ramat.) is one of the largest cut flowers in the world. Phosphate transporter Pht1 family member CmPht1;2 protein (CmPT2) plays an important role in response to low-phosphate (LP) stress in chrysanthemum. Post-translational modification (PTM) can modulate the function of proteins in multiple ways. Here, we used yeast and rice systems to study the role of putative PTM in CmPT2 by determining the effect of mutation of key amino acid residues of putative glycosylation, phosphorylation, and myristoylation sites. We chose nine amino acid residues in the putative PTM sites and mutated them to alanine (A) (Cmphts). CmPT2 recovered the growth of yeast strain MB192 under LP conditions. However, G84A, G222A, T239A, Y242A, and N422A mutants could not grow normally under LP conditions. Analysis of phosphorus absorption kinetics showed that the Km of CmPT2 was 65.7 μM. Among the nine Cmphts, the expression of five with larger Km (124.4-397.5 μM) than CmPT2 was further evaluated in rice. Overexpression of CmPT2-OE increased plant height, effective panicle numbers, branch numbers, and yield compared with that of wild type \'Wuyunjing No. 7\' (W7). Overexpression of Cmphts-OE led to decreased plant height and effective panicle numbers compared with that of the CmPT2-OE strain. The Pi content in roots of CmPT2-OE was higher than that of the W7 under both high (normal) phosphate (HP) and LP conditions. However, the Pi content in the leaves and roots was significantly lower in the N422A-OE strain than in the CmPT2-OE strain under both HP and LP conditions. Under LP conditions, the phosphorus starvation response (PSR) genes in CmPT2-OE were inhibited at the transcription level. The expression patterns of phosphorus-related genes in T239A, Y242A, and N422A-OE under LP conditions were different from those of CmPT2-OE. In conclusion, these five post-translational modification residues of CmPT2 play key roles in modulating the function of CmPT2. This work boosters our understanding of the function of phosphate transporters and provides genetic resources for improving the efficiency of phosphorus utilization in crop plants.