State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Triticeae Research Institute, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, China.
Key Laboratory of Crop Genetic Resources and Improvement, Ministry of Education, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, China.
J Appl Genet. 2021 Feb;62(1):17-25. doi: 10.1007/s13353-020-00588-y. Epub 2020 Oct 15.
The grain protein content (GPC) in modern wheat is inherently low. Wild emmer wheat (Triticum turgidum ssp. dicoccoides, 2n = 4x = 28, AABB) gene pool harbors wide genotypic variations in GPC. However, the characterization of candidate genes associated with high GPC is a challenge due to the complex characteristic of this trait. In the current study, we performed RNA-seq analysis on developing grains of wild emmer genotype D1, common wheat CN16, and their hexaploid wide hybrid BAd107-4 with contrasting GPC. We have found a total of 39,795 expressed genes on chromosomes A and B, of which 24,152 were shared between D1, CN16, and BAd107-4. From 1744 differentially expressed genes (DEGs), 1203 were downregulated and 541 were upregulated in the high GPC (D1+BAd107-4) compared with low GPC (CN16) groups. The majority of DEGs were associated with protein processing in endoplasmic reticulum, starch and sucrose metabolism, galactose metabolism, and protein export pathways. Expression levels of nine randomly selected genes were verified by qRT-PCR, which was consistent with the transcriptome data. The present database will help us to understand the potential regulation networks underlying wheat grain protein accumulation and provide the foundation for simultaneous improvement of grain protein content and yield in wheat breeding programs.
现代小麦的籽粒蛋白质含量（GPC）本来就低。野生二粒小麦（Triticum turgidum ssp. dicoccoides，2n=4x=28，AABB）基因库中存在 GPC 广泛的基因型变异。然而，由于该性状的复杂性，与高 GPC 相关的候选基因的特征描述是一个挑战。在本研究中，我们对具有不同 GPC 的野生二粒小麦基因型 D1、普通小麦 CN16 及其六倍体广泛杂种 BAd107-4 的发育籽粒进行了 RNA-seq 分析。我们总共在染色体 A 和 B 上发现了 39795 个表达基因，其中 24152 个在 D1、CN16 和 BAd107-4 之间共享。在 1744 个差异表达基因（DEGs）中，1203 个在高 GPC（D1+BAd107-4）组中下调，541 个在低 GPC（CN16）组中上调。大多数 DEGs 与内质网蛋白质加工、淀粉和蔗糖代谢、半乳糖代谢以及蛋白质输出途径有关。随机选择的 9 个基因的表达水平通过 qRT-PCR 进行了验证，与转录组数据一致。本数据库将帮助我们了解小麦籽粒蛋白质积累的潜在调控网络，并为小麦育种计划中同时提高籽粒蛋白质含量和产量提供基础。
