期刊：Plant Physiology
主題：NRT1.1磷酸化調(diào)節(jié)側(cè)根發(fā)育的機制
標題：Phosphorylation-mediated dynamics of nitrate transceptor NRT1.1 regulate auxin flux and nitrate signaling in lateral root growth
影響因子：6.305
檢測指標：IAA流速
檢測部位：酵母細胞
IAA流速流實驗處理方法：
轉(zhuǎn)化酵母細胞在SD-URA培養(yǎng)基長到對數(shù)期，轉(zhuǎn)至SG-URA培養(yǎng)基[SD-URA培養(yǎng)基中的dextrose替換為2%（m/v）galactose]上，培養(yǎng)24-48小時，誘導(dǎo)NRT1.1，T101A，T101D，mRuby表達。離心收集并制成SG-URA懸液。
IAA流速流實驗測試液成份：
0.5 μM IAA, 2% (m/v) galactose, 0.3 mM MES, pH 5.8
作者：北京林業(yè)大學(xué)單曉昳、林金星、張曦
英文摘要
The dual-affinity nitrate transceptor NITRATE TRANSPORTER 1.1 (NRT1.1) has two modes of transport and signaling, governed by threonine101 (T101) phosphorylation. NRT1.1 regulates lateral root (LR) development by modulating nitrate-dependent basipetal auxin export and nitrate-mediated signal transduction.
Here, using the Arabidopsis thaliana NRT1.1T101D phosphomimetic and NRT1.1T101A non-phosphorylatable mutants, we found that the phosphorylation state of NRT1.1 plays a key role in NRT1.1 function during LR development. Single-particle tracking revealed that phosphorylation affected NRT1.1 spatiotemporal dynamics. The phosphomimetic NRT1.1T101D form showed fast lateral mobility and membrane partitioning that facilitated auxin flux under low-nitrate conditions.
By contrast, non-phosphorylatable NRT1.1T101A showed low lateral mobility and oligomerized at the plasma membrane (PM), where it induced endocytosis via the clathrin-mediated endocytosis and microdomain-mediated endocytosis pathways under high-nitrate conditions.
These behaviors promoted LR development by suppressing NRT1.1-controlled auxin transport on the PM and stimulating Ca2+-ARABIDOPSIS NITRATE REGULATED 1 (ANR1) signaling from the endosome.
中文摘要（谷歌機翻）
雙親和**鹽轉(zhuǎn)運蛋白NITRATE TRANSPORTER 1.1（NRT1.1）具有兩種運輸和信號傳導(dǎo)模式，由蘇氨酸101（T101）磷酸化控制。 NRT1.1通過調(diào)節(jié)**鹽依賴性堿基生長素輸出和**鹽介導(dǎo)的信號轉(zhuǎn)導(dǎo)來調(diào)節(jié)側(cè)根（LR）發(fā)育。
在這里，使用擬南芥NRT1.1T101D磷酸化和NRT1.1T101A非磷酸化突變體，我們發(fā)現(xiàn)NRT1.1的磷酸化狀態(tài)在LR發(fā)育期間在NRT1.1功能中起關(guān)鍵作用。單粒子追蹤顯示磷酸化影響NRT1.1時空動態(tài)。磷酸化模擬NRT1.1T101D形式顯示出快速的側(cè)向移動性和膜分配，其促進了在低**鹽條件下的生長素通量。
相比之下，不可磷酸化的NRT1.1T101A顯示出低的側(cè)向遷移率并且在質(zhì)膜（PM）處寡聚化，其在高**鹽條件下通過網(wǎng)格蛋白介導(dǎo)的內(nèi)吞作用和微區(qū)介導(dǎo)的胞吞作用途徑誘導(dǎo)內(nèi)吞作用。
這些行為通過抑制PM上的NRT1.1控制的生長素轉(zhuǎn)運并刺激來自內(nèi)體的Ca2 + -ARABIDOPSIS**鹽調(diào)節(jié)1（ANR1）信號傳導(dǎo)來促進LR發(fā)展。
酵母細胞IAA流檢測
對照、NRT1.1、T101A、T101D轉(zhuǎn)化酵母菌的IAA流（外排）結(jié)果。