Metabolic click-labeling with a fucose analog reveals pectin delivery, architecture, and dynamics in Arabidopsis cell walls
Metabolic click-labeling with a fucose analog reveals pectin delivery, architecture, and dynamics in Arabidopsis cell walls
复制标题
DOI：
10.1073/pnas.1120429109
复制
发表时间：
2012-01-24
影响因子：
11.1
通讯作者：
Somerville, Chris R.
中科院分区：
文献类型：
--
作者：
Anderson, Charles T.;Wallace, Ian S.;Somerville, Chris R.
富含多糖的细胞壁是影响细胞分裂和生长的植物的定义特征，但由于缺乏合适的化学探针，细胞壁组织和动力学的许多细节是未知的。使用糖类似物与点击化学兼容的代谢标记有可能为细胞壁结构和动力学提供新的见解。使用这种方法，我们发现，一个炔基化岩藻糖类似物（FucAl）代谢纳入拟南芥根的细胞壁，并在果胶鼠李糖半乳糖醛酸-I（RG-I）中存在的一个显着的分数的掺入FucAl。时程实验表明，含FucAl的RG-I首先定位在细胞壁中，作为均匀分布的斑点，其可能标记囊泡介导的新多糖递送至生长细胞壁的位点。此外，我们还发现，FucAl的掺入模式沿根的发育梯度沿着有显著差异。利用脉冲追踪实验，我们还发现，果胶网络是重新定位在伸长根表皮细胞。这些结果揭示了以前未描述的细节多糖的交付，组织和动态细胞壁。
Polysaccharide-rich cell walls are a defining feature of plants that influence cell division and growth, but many details of cell-wall organization and dynamics are unknown because of a lack of suitable chemical probes. Metabolic labeling using sugar analogs compatible with click chemistry has the potential to provide new insights into cell-wall structure and dynamics. Using this approach, we found that an alkynylated fucose analog (FucAl) is metabolically incorporated into the cell walls of Arabidopsis thaliana roots and that a significant fraction of the incorporated FucAl is present in pectic rhamnogalacturonan-I (RG-I). Time-course experiments revealed that FucAl-containing RG-I first localizes in cell walls as uniformly distributed punctae that likely mark the sites of vesicle-mediated delivery of new polysaccharides to growing cell walls. In addition, we found that the pattern of incorporated FucAl differs markedly along the developmental gradient of the root. Using pulse-chase experiments, we also discovered that the pectin network is reoriented in elongating root epidermal cells. These results reveal previously undescribed details of polysaccharide delivery, organization, and dynamics in cell walls.