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Summary: Understanding the mechanisms of iron trafficking in plants is key to enhancing the nutritional quality of crops. Because it is difficult to image iron in transit, we currently have an incomplete picture of the route(s) of iron translocation in developing seeds and how the tissue‐specific distribution is established.We have used a novel approach, combining iron‐57 (57Fe) isotope labelling and nanoscale secondary ion mass spectrometry (NanoSIMS), to visualize iron translocation between tissues and within cells in immature wheat grain, Triticum aestivum.This enabled us to track the main route of iron transport from maternal tissues to the embryo through the different cell types. Further evidence for this route was provided by genetically diverting iron into storage vacuoles, with confirmation provided by histological staining and transmission electron microscopy energy dispersive X‐ray spectroscopy (TEM‐EDS). Almost all iron in both control and transgenic grains was found in intracellular bodies, indicating symplastic rather than apoplastic transport. Furthermore, a new type of iron body, highly enriched in 57Fe, was observed in aleurone cells and may represent iron being delivered to phytate globoids.Correlation of the 57Fe enrichment profiles obtained by NanoSIMS with tissue‐specific gene expression provides an updated model of iron homeostasis in cereal grains with relevance for future biofortification strategies. [ABSTRACT FROM AUTHOR]

In ubiquitin-mediated post-translational modifications, RING finger families are emerged as important E3 ligases in regulating biological processes. Amylose and amylopectin are two major constituents of starch in wheat seed endosperm. Studies have been found the beneficial effects of high amylose or resistant starch on health. The ubiquitin-mediated post-translational regulation of key enzymes for amylose/amylopectin biosynthesis (GBSSI and SBEII) is still unknown. In this study, the genome-wide analysis identified 1272 RING domains in 1255 proteins in wheat, which is not reported earlier. The identified RING domains classified into four groups—RING-H2, RING-HC, RING-v, RING-G, based on the amino acid residues (Cys, His) at metal ligand positions and the number of residues between them with the predominance of RING-H2 type. A total of 1238 RING protein genes were found to be distributed across all 21 wheat chromosomes. Among them, 1080 RING protein genes were identified to show whole genome/segmental duplication within the hexaploid wheat genome. In silico expression analysis using transcriptome data revealed 698 RING protein genes, having a possible role in seed development. Based on differential gene expression and correlation analysis of 36 RING protein genes in diverse (high and low) amylose mutants and parent, 10 potential RING protein genes found to be involved in high amylose biosynthesis and significantly associated with two starch biosynthesis genes; GBSSI and SBEIIa. Characterization of mutant lines using next-generation sequencing method identified unique mutations in 698 RING protein genes. This study signifies the putative role of RING-type E3 ligases in amylose biosynthesis and this information will be helpful for further functional validation and its role in other biological processes in wheat. [ABSTRACT FROM AUTHOR]

PurposeTo transfer the 2S chromosomal fragment(s) ofAegilops kotschyi(2Sk) into the bread wheat genome which could lead to the biofortification of wheat with high grain iron and zinc content. Materials and methodsWheat-Ae. kotschyi2A/2Sksubstitution lines with high grain iron and zinc content were used to transfer the gene/loci for high grain Fe and Zn content into wheat using seed irradiation approach. ResultsBread wheat plants derived from 40 krad-irradiated seeds showed the presence of univalents and multivalents during meiotic metaphase-I. Genomic in situ hybridization analysis of seed irradiation hybrid F2seedlings showed several terminal and interstitial signals indicated the introgression ofAe. kotschyichromosome segments. This proves the efficacy of seed radiation hybrid approach in gene transfer experiments. All the radiation-treated hybrid plants with high grain Fe and Zn content were analyzed with wheat group 2 chromosome-specific polymorphic simple sequence repeat markers to identify the introgression of small alien chromosome fragment(s). ConclusionRadiation-induced hybrids showed more than 65% increase in grain iron and 54% increase in Zn contents with better harvest index than the elite wheat cultivar WL711 indicating effective and compensating translocations of 2Skfragments into wheat genome. [ABSTRACT FROM AUTHOR]

Resistant starch (RS) also known as healthy starch has shown several health benefits. Enhancing the RS through genetic modification approaches has huge commercial importance. Regulatory RNA like long non-coding RNA (lncRNA) plays an important role in gene regulation. In this study, we mined 63 transcriptome datasets of wheat belonging to 35 genotypes representing two seed developmental stages. Contrasting expression of a subset of lncRNAs in RS mutant lines compared to parent wheat variety 'C 306' signifies their probable role in RS biosynthesis. Further, lncRNA- TCONS_00130663 showed strong positive correlation (r2 = 1) with LYPL gene and strong negative correlation with SBEIIb (r2 = −0.94). We found TCONS_00130663 as positive regulator of LYPL gene through interaction with miR1128. Based on relative expression, in silico interaction and DSC analysis we hypothesize the dual role of TCONS_00130663 in RS type 2 and type 5. The study provides a useful resource for functional mechanism of lncRNAs. • 443 lncRNA were identified in wheat grain through in-silico prediction. • Contrasting expression of lncRNAs signifies their role in resistant starch (RS) biosynthesis. • TCONS_00130663 interacting with mir-1128 possibly regulates LYPL gene for lipid biosynthesis. • Strong correlation of TCONS_00130663 with SBEIIb and LYPL suggesting its possible role in RS2 and RS5 formation [ABSTRACT FROM AUTHOR]