Non-targeted and targeted protein movement through plasmodesmata in leaves in different developmental and physiological states
Non-targeted and targeted protein movement through plasmodesmata in leaves in different developmental and physiological states
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DOI：
10.1104/pp.125.4.1802
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发表时间：
2001-04-01
期刊：
影响因子：
7.4
通讯作者：
Zambryski, PC
中科院分区：
文献类型：
--
作者：
Crawford, KM;Zambryski, PC
植物细胞依靠胞间连丝进行小信号分子以及较大信息大分子如蛋白质的细胞间运输。一个绿色荧光蛋白（GFP）报告和低压微粒轰击被用来量化的程度，共质体连续性细胞之间的叶在不同的发育阶段和不同的生长条件。观察到胞间连丝对GFP的运输关闭或扩张以允许GFP的运输。在库叶中，34%至67%的细胞转运GFP（27 kD），30%至46%的细胞转运双GFP（54 kD）。在过渡运输叶减少; 21%和46%之间和2%和9%之间的细胞运输单和双GFP，分别。因此，叶龄极大地影响细胞非选择性交换蛋白质的能力。此外，允许GFP或双GFP运动的细胞的数量对生长条件敏感，因为温室生长的植物比培养生长的植物表现出更高的扩散速率。这些研究表明，叶细胞胞间连丝是动态的，并没有一套大小排阻限制。我们还研究了融合到GFP的烟草花叶病毒运动蛋白P30：：GFP的靶向运动。这种58 kD的融合蛋白定位于胞间连丝，始终从高达78%的转染细胞，是不敏感的发育年龄或生长条件。含有扩张的胞间连丝的细胞的相对数量在不同的烟草物种之间变化，与烟草clevelandii表现出更大的蛋白质扩散比烟草。
Plant cells rely on plasmodesmata for intercellular transport of small signaling molecules as well as larger informational macromolecules such as proteins. A green fluorescent protein (GFP) reporter and low-pressure microprojectile bombardment were used to quantify the degree of symplastic continuity between cells of the leaf at different developmental stages and under different growth conditions. Plasmodesmata were observed to be closed to the transport of GFP or dilated to allow the traffic of GFP. In sink leaves, between 34% and 67% of the cells transport GFP (27 kD), and between 30% and 46% of the cells transport double GFP (54 kD). In leaves in transition transport was reduced; between 21% and 46% and between 2% and 9% of cells transport single and double GFP, respectively. Thus, leaf age dramatically affects the ability of cells to exchange proteins nonselectively. Further, the number of cells allowing GFP or double GFP movement was sensitive to growth conditions because greenhouse-grown plants exhibited higher diffusion rates than culture-grown plants. These studies reveal that leaf cell plasmodesmata are dynamic and do not have a set size exclusion limit. We also examined targeted movement of the movement protein of tobacco mosaic virus fused to GFP, P30::GFP. This 58-kD fusion protein localizes to plasmodesmata, consistently transits from up to 78% of transfected cells, and was not sensitive to developmental age or growth conditions. The relative number of cells containing dilated plasmodesmata varies between different species of tobacco, with Nicotiana clevelandii exhibiting greater diffusion of proteins than Nicotiana tabacum.