Frontiers in Plant Science ( IF 5.6 ) Pub Date : 2020-12-10 , DOI: 10.3389/fpls.2020.609923 Vikram Singh , Hanita Zemach , Sara Shabtai , Roni Aloni , Jun Yang , Peng Zhang , Lidiya Sergeeva , Wilco Ligterink , Nurit Firon
Sweetpotato is an important food crop globally, serving as a rich source of carbohydrates, vitamins, fiber, and micronutrients. Sweetpotato yield depends on the modification of adventitious roots into storage roots. The underlying mechanism of this developmental switch is not fully understood. Interestingly, storage-root formation is manifested by formation of starch-accumulating parenchyma cells and bulking of the distal part of the root, while the proximal part does not show bulking. This system, where two parts of the same adventitious root display different developmental fates, was used by us in order to better characterize the anatomical, physiological, and molecular mechanisms involved in sweetpotato storage-root formation. We show that, as early as 1 and 2 weeks after planting, the proximal part of the root exhibited enhanced xylem development together with increased/massive lignin deposition, while, at the same time, the distal root part exhibited significantly elevated starch accumulation. In accordance with these developmental differences, the proximal root part exhibited up-regulated transcript levels of sweetpotato orthologs of
中文翻译:
甘薯不定根的近端和远端部分在根构型,木质素和淀粉代谢及其发育命运方面表现出差异
甘薯是全球重要的粮食作物,是碳水化合物,维生素,纤维和微量营养素的丰富来源。甘薯产量取决于不定根到贮藏根的修饰。这种发展开关的潜在机制尚未完全了解。有趣的是,贮藏根的形成表现为淀粉积累薄壁细胞的形成和根的远端部分的膨大,而近端部分则没有膨大。为了更好地表征甘薯贮藏根形成过程中涉及的解剖,生理和分子机制,我们使用了该系统,其中不定根的两个部分显示不同的发育命运。我们表明,早在种植后1和2周,根的近端部分表现出增强的木质部发育以及木质素沉积的增加/大量,同时,远端的根部分表现出明显的淀粉积累增加。根据这些发育差异,近根部分显示了甘薯直系同源基因的转录水平上调。