Division of Quality and Basic Sciences, ICAR-Indian Institute of Wheat and Barley Research (IIWBR), Karnal, 132001, Haryana, India.
Director, ICAR-Indian Institute of Wheat and Barley Research (IIWBR), Karnal, 132001, Haryana, India.
J Biotechnol. 2020 Jun 10;316:46-55. doi: 10.1016/j.jbiotec.2020.03.015. Epub 2020 Apr 16.
Wheat (T. aestivum L.) is the second most important staple food crop consumed in the form of various end-use products across the world. However, it contains lower concentrations of Fe and Zn leading to micronutrient deficiency in human beings where wheat is the sole diet. Therefore, increasing grain Fe/Zn content in wheat has become priority in wheat breeding programmes across the world. Understanding the molecular mechanism of Fe/Zn transport and accumulation in grains is required to expedite the breeding process. For this purpose, whole seedling transcriptome analysis was conducted in four wheat genotypes (CRP 1660, Sonora 64, Vinata, : high, and DBW17: low) differing in grain Fe/Zn content under controlled and Fe/Zn deficient conditions. Twenty eight key transcripts involved in phytosiderophore biosynthesis, Fe/Zn uptake and transport were identified. Expression analysis of 12 of the transcripts using qPCR was conducted in seedling stage and flag leaf which exhibited greater differential accumulation in CRP 1660 followed by Vinata, Sonora 64 and DBW 17 in both flag leaf and seedling. However, there was significantly higher differential accumulation of the transcripts in flag leaf as compared to seedling. In CRP 1660, transcripts pertaining to phytosiderophore biosynthesis like DMAS1-B, NRAMP2 and NAAT2-D showed greater accumulation. Additionally, corresponding miRNAs were also identified for these 28 transcripts. The findings will help in better understanding of molecular basis of Fe/Zn transport and accumulation in grain and subsequent utilization in breeding to improve Fe/Zn content in wheat grain.
小麦（T. aestivum L.）是全世界以各种最终用途产品形式消费的第二大主要主食作物。然而，它的铁和锌含量较低，导致以小麦为主食的人类出现微量营养素缺乏。因此，增加小麦籽粒中的铁/锌含量已成为全世界小麦育种计划的首要任务。为了加快这一进程，需要了解铁/锌在谷物中的运输和积累的分子机制。为此，在四个小麦基因型（CRP 1660、Sonora 64、Vinata：高，和 DBW17：低）中进行了整个幼苗转录组分析，这些基因型在控制和铁/锌缺乏条件下的籽粒铁/锌含量存在差异。鉴定出 28 个与植物铁载体生物合成、铁/锌吸收和运输有关的关键转录本。使用 qPCR 在幼苗阶段和旗叶中对其中 12 个转录本进行了表达分析，结果表明 CRP 1660 的表达差异最大，其次是 Vinata、Sonora 64 和 DBW 17，在幼苗和旗叶中均如此。然而，与幼苗相比，旗叶中的转录本差异积累更为显著。在 CRP 1660 中，与植物铁载体生物合成有关的转录本，如 DMAS1-B、NRAMP2 和 NAAT2-D 的积累量较大。此外，还为这 28 个转录本鉴定了相应的 miRNA。这些发现将有助于更好地理解铁/锌在谷物中的运输和积累的分子基础，并随后利用这些发现来改善小麦籽粒中的铁/锌含量。
