Sucrose starvation induces the degradation of proteins in trans-Golgi network and secretory vesicle cluster in tobacco BY-2 cells
Sucrose starvation induces the degradation of proteins in trans-Golgi network and secretory vesicle cluster in tobacco BY-2 cells
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DOI：
10.1080/09168451.2020.1756736
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发表时间：
2020-04-26
影响因子：
1.6
通讯作者：
Matsuoka，Ken
中科院分区：
文献类型：
--
作者：
Oda，Yamato;Asatsuma，Satoru;Matsuoka，Ken
内膜运输系统起始于内质网（ER），延续到高尔基体和随后的隔室，称为高尔基体网络（TGN）。我们发现，SUT 2，烟草蔗糖转运蛋白的直系同源物，并定位于TGN，蔗糖饥饿条件下显着下降。定位于TGN和分泌囊泡簇（SVC）的烟草SNARE蛋白SYP 41也在饥饿下减少。同样，SCAMP 2-RFP融合蛋白定位于TGN，SVC和质膜（PM），在饥饿下仅分布于PM中。在相同的饥饿条件下，蛋白质的分泌并没有受到抑制，但果胶在细胞壁上的沉积受到抑制。这些数据表明，TGN中的蛋白质组成和SVC的存在受到糖可用性的调节。此外，我们的发现以及SVC参与果胶分泌表明果胶的合成和运输受胞外糖的水平调节。缩写ER：内质网; GI-TGN：高尔基体释放的独立TGN; GFP：绿色荧光蛋白; mRFP：单体红色荧光蛋白; P4 H1.1：脯氨酰4-羟化酶1.1; PM：质膜; SCAMP 2：分泌载体膜蛋白2; SUT 2：蔗糖转运蛋白2; SVC：分泌囊泡簇; SYP 41：植物41的突触融合蛋白; TGN：高尔基体网络; YFP：黄色荧光蛋白
Endomembrane transport system begins at the endoplasmic reticulum (ER), continues to the Golgi apparatus and subsequent compartment calledtrans-Golgi network (TGN). We found that SUT2, a tobacco sucrose-transporter ortholog and was localized in the TGN, decreased significantly under a sucrose-starvation condition. The tobacco SNARE protein SYP41, localized in the TGN and secretory vesicle cluster (SVC), also decreased under the starvation. Similarly, the SCAMP2-RFP fusion protein, which is localized in TGN, SVC, and plasma membrane (PM), was distributed solely in the PM under the starvation. Under the same starvation condition, protein secretion was not arrested but pectin deposition to cell wall was suppressed. These data indicated that the protein composition in TGN and existence of the SVC are regulated by sugar availability. Furthermore, our findings as well as the involvement of SVC in pectin secretion suggested that synthesis and transport of pectin are regulated by the level of extracellular sugars.AbbreviationsER: endoplasmic reticulum; GI-TGN: Golgi-released independent TGN; GFP: green fluorescent protein; mRFP: monomeric red fluorescent protein; P4H1.1: prolyl 4-hydroxylase 1.1; PM: plasma membrane; SCAMP2: secretory carrier membrane protein 2; SUT2: sucrose transporter 2; SVC: secretory vesicle cluster; SYP41: syntaxin of plant 41; TGN:trans-Golgi network; YFP: yellow fluorescent protein