College of Agronomy, Henan Agricultural University/Collaborative Innovation Center of Henan Grain Crops, Zhengzhou, 450002, China.
College of Agronomy, National Key Laboratory of Crop Genetics and Germplasm Enhancement/JCIC-MCP, Nanjing Agricultural University, Nanjing, 210095, China.
BMC Genomics. 2018 Apr 2;19(1):228. doi: 10.1186/s12864-018-4607-z.
Spike architecture mutants in tetraploid wheat (Triticum turgidum L., 2n = 28, AABB) have a distinct morphology, with parts of the rachis node producing lateral meristems that develop into ramified spikelete (RSs) or four-rowed spikelete (FRSs). The genetic basis of RSs and FRSs has been analyzed, but little is known about the underlying developmental mechanisms of the lateral meristem. We used isobaric tags for relative and absolute quantitation (iTRAQ) to perform a quantitative proteomic analysis of immature spikes harvested from tetraploid near-isogenic lines of wheat with normal spikelete (NSs), FRSs, and RSs and investigated the molecular mechanisms of lateral meristem differentiation and development. This work provides valuable insight into the underlying functions of the lateral meristem and how it can produce differences in the branching of tetraploid wheat spikes.
Using an iTRAQ-based shotgun quantitation approach, 104 differential abundance proteins (DAPs) with < 1% false discovery rate (FDR) and a 1.5-fold change (> 1.50 or < 0.67) were identified by comparing FRS with NS and RS with NS genotypes. To determine the functions of the proteins, 38 co-expressed DAPs from the two groups were annotated using the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analytical tools. We discovered that proteins involved in "post-embryonic development" and "metabolic pathways" such as carbohydrate and nitrogen metabolism could be used to construct a developmentally associated network. Additionally, 6 out of 38 DAPs in the network were analyzed using quantitative real-time polymerase chain reaction, and the correlation coefficient between proteomics and qRT-PCR was 0.7005. These key genes and proteins were closely scrutinized and discussed.
Here, we predicted that DAPs involved in "post-embryonic development" and "metabolic pathways" may be responsible for the spikelete architecture changes in FRS and RS. Furthermore, we discussed the potential function of several vital DAPs from GO and KEGG analyses that were closely related to histone modification, ubiquitin-mediated protein degradation, transcription factors, carbohydrate and nitrogen metabolism and heat shock proteins (HSPs). This work provides valuable insight into the underlying functions of the lateral meristem in the branching of tetraploid wheat spikes.
四倍体小麦（Triticum turgidum L.，2n=28，AABB）中的刺突结构突变体具有独特的形态，部分穗轴节产生侧生分生组织，发育成分枝小穗（RS）或四行小穗（FRS）。已经分析了 RS 和 FRS 的遗传基础，但对侧生分生组织的潜在发育机制知之甚少。我们使用等重同位素标记相对和绝对定量（iTRAQ）技术对来自四倍体近等基因系的未成熟穗进行定量蛋白质组学分析，这些近等基因系的小穗正常（NS）、FRS 和 RS，并研究了侧生分生组织分化和发育的分子机制。这项工作为侧生分生组织的潜在功能以及它如何在四倍体小麦穗分枝中产生差异提供了有价值的见解。
通过比较 FRS 与 NS 和 RS 与 NS 基因型，使用基于 iTRAQ 的shotgun 定量方法，在比较 FRS 与 NS 和 RS 与 NS 基因型时，鉴定到 104 个差异丰度蛋白（DAP），具有<1%的假发现率（FDR）和 1.5 倍变化（>1.50 或<0.67）。为了确定蛋白质的功能，使用 Gene Ontology 和 Kyoto Encyclopedia of Genes and Genomes 分析工具对来自两组的 38 个共表达 DAP 进行注释。我们发现，参与“胚后发育”和“碳水化合物和氮代谢等代谢途径”的蛋白质可用于构建发育相关网络。此外，网络中的 38 个 DAP 中的 6 个通过定量实时聚合酶链反应进行了分析，蛋白质组学和 qRT-PCR 之间的相关系数为 0.7005。对这些关键基因和蛋白质进行了深入分析和讨论。
在这里，我们预测参与“胚后发育”和“代谢途径”的 DAP 可能负责 FRS 和 RS 中小穗结构的变化。此外，我们还讨论了来自 GO 和 KEGG 分析的几个重要 DAP 的潜在功能，这些 DAP 与组蛋白修饰、泛素介导的蛋白降解、转录因子、碳水化合物和氮代谢以及热休克蛋白（HSPs）密切相关。这项工作为四倍体小麦穗分枝中侧生分生组织的潜在功能提供了有价值的见解。
