Transcriptional regulation of plant phosphate transporters
Transcriptional regulation of plant phosphate transporters
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DOI：
10.1073/pnas.96.10.5868
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发表时间：
1999-05-11
影响因子：
11.1
通讯作者：
Raghothama, KG
中科院分区：
文献类型：
--
作者：
Muchhal, US;Raghothama, KG
植物根系主要通过高亲和力无机磷酸盐（P-i）转运体获得磷。P-i转运体转录本在P-i饥饿时高度诱导，当P-i补给时也导致P-i摄取增强。利用针对番茄P-i转运蛋白（由LePT1编码）的一种特异性抗体，我们发现在P-i饥饿下，LePT1转录物的增加导致转运蛋白的同时增加，这表明对P-i获取有转录调控，LePT1蛋白在番茄根部响应P-i饥饿而迅速积累。转运蛋白的积累水平取决于介质中的P-i浓度，并且在P-i再补给时是可逆的。在P-i饥饿的情况下，LePT1蛋白沿着根部积累，主要定位于质膜。这些结果清楚地表明，植物在缺磷过程中通过合成额外的转运体分子来增加其吸收磷的能力。
Phosphorus is acquired by plant roots primarily via the high-affinity inorganic phosphate (P-i) transporters. The transcripts for P-i transporters are highly inducible upon P-i starvation, which also results in enhanced P-i uptake when P-i is resupplied. Using antibodies specific to one of the tomato P-i transporters (encoded by LePT1), we show that an increase in the LePT1 transcript under P-i starvation leads to a concurrent increase in the transporter protein, suggesting a transcriptional regulation for P-i acquisition, LePT1 protein accumulates rapidly in tomato roots in response to P-i starvation. The level of transporter protein accumulation depends on the P-i concentration in the medium, and it is reversible upon resupply of P-i. LePT1 protein accumulates all along the roots under P-i starvation and is localized primarily in the plasma membranes. These results clearly demonstrate that plants increase their capacity for P-i uptake during P-i starvation by synthesis of additional transporter molecules.