Sabanci University, Biological Sciences and Bioengineering Program, Tuzla, Istanbul, Turkey.
Plant Physiol Biochem. 2011 Mar;49(3):346-51. doi: 10.1016/j.plaphy.2011.01.016. Epub 2011 Jan 21.
Drought is one of the major causes of dramatic yield loss in crop plants. Knowledge of how to alleviate this loss is still limited due to the complexity of both the stress condition and plant responses. Wild emmer wheat (Triticum turgidum ssp. dicoccoides) is a potential source of important drought-resistance genes for its cultivated relatives. The gene for an emmer DRE-binding protein, TdicDRF1, was cloned and shown to be drought-responsive with orthologs in other plants. This is the first report of the cloning of TdicDRF1, and its expression was further characterized by RT-PCR in both drought-sensitive and drought-resistant accessions of Triticum dicoccoides. Analysis of the AP2/ERF DNA-binding domain of TdicDRF1 as a GST-fusion protein and its binding to DRE by electrophoretic mobility shift assay (EMSA) indicate functional differences between wheat DREBs and those characterized in Arabidopsis thaliana. DREB expression increased in drought-stressed roots, correlating with the RT-PCR results, but not in leaf, showing that tissue-specific regulation occurs at the protein level. Hence, the DREB-DRE interaction undergoes subtle multi-level regulation.
干旱是作物产量大幅下降的主要原因之一。由于胁迫条件和植物反应的复杂性，减轻这种损失的知识仍然有限。野生二粒小麦（Triticum turgidum ssp. dicoccoides）是其栽培近缘种重要抗旱基因的潜在来源。克隆了一个野生二粒小麦 DRE 结合蛋白基因 TdicDRF1，其在其他植物中具有同源物，表现出对干旱的响应。这是克隆 TdicDRF1 的第一个报道，并用 RT-PCR 进一步分析了 Triticum dicoccoides 中对干旱敏感和有抗性的品系。通过 GST 融合蛋白分析 TdicDRF1 的 AP2/ERF DNA 结合域及其与 DRE 的电泳迁移率变动分析（EMSA）结合表明，小麦 DREBs 与拟南芥中鉴定的 DREBs 之间存在功能差异。干旱胁迫下，根中 DREB 的表达增加，与 RT-PCR 结果一致，但在叶中没有表达，这表明在蛋白质水平上发生了组织特异性调控。因此，DREB-DRE 相互作用经历了微妙的多层次调控。
