The dynamics of protein body formation in developing wheat grain.
The dynamics of protein body formation in developing wheat grain.
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蛋白质体形成的动力学在发展小麦颗粒中。
DOI：
10.1111/pbi.12549
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发表时间：
2016-09
影响因子：
13.8
通讯作者：
Shewry PR
中科院分区：
文献类型：
--
作者：
Moore KL;Tosi P;Palmer R;Hawkesford MJ;Grovenor CR;Shewry PR
小麦是人类和牲畜饮食中蛋白质的主要来源，但我们对决定发育中胚乳蛋白质合成模式的机制知之甚少。我们已经使用了富集与15 N谷氨酰胺和NanoSIMS成像的组合，以建立蛋白质合成所需的底物从其在胚乳腔中的入口点径向运输穿过淀粉质胚乳组织，然后集中在糊粉层正下方的细胞中。这种运输在籽粒发育过程中持续发生，但在后期可能较慢。虽然较老的淀粉胚乳细胞倾向于含有由小蛋白体融合形成的较大的蛋白质沉积物，但小的高度富集的蛋白体也可能存在于相同的细胞中。这表明，在较老和较年轻的淀粉胚乳细胞以及组织的所有区域中，蛋白体起始都是一个连续的过程。用特异性抗体进行免疫标记表明，富集模式与蛋白体中谷蛋白的含量无关。除了提供有关蛋白质沉积动力学的新信息外，该研究还展示了NanoSIMS和同位素标记在研究植物组织复杂发育过程中的更广泛用途。
Wheat is a major source of protein in the diets of humans and livestock but we know little about the mechanisms that determine the patterns of protein synthesis in the developing endosperm. We have used a combination of enrichment with 15N glutamine and NanoSIMS imaging to establish that the substrate required for protein synthesis is transported radially from its point of entrance in the endosperm cavity across the starchy endosperm tissues, before becoming concentrated in the cells immediately below the aleurone layer. This transport occurs continuously during grain development but may be slower in the later stages. Although older starchy endosperm cells tend to contain larger protein deposits formed by the fusion of small protein bodies, small highly enriched protein bodies may also be present in the same cells. This shows a continuous process of protein body initiation, in both older and younger starchy endosperm cells and in all regions of the tissue. Immunolabeling with specific antibodies shows that the patterns of enrichment are not related to the contents of gluten proteins in the protein bodies. In addition to providing new information on the dynamics of protein deposition, the study demonstrates the wider utility of NanoSIMS and isotope labelling for studying complex developmental processes in plant tissues.