PDF(Pubmed)
Abstract：
Fusarium graminearum, the causal agent of Fusarium head blight (FHB), produces various mycotoxins that contaminate wheat grains and cause profound health problems in humans and animals. Deoxynivalenol (DON) is the most common trichothecene found in contaminated grains. Our previous study showed that Arabidopsis-expressing F. graminearum trichothecene 3-O-acetyltransferase (FgTRI101) converted DON to 3-acetyldeoxynivalenol (3-ADON) and excreted it outside of Arabidopsis cells. To determine if wheat can convert and excrete 3-ADON and reduce FHB and DON contamination, FgTRI101 was cloned and introduced into wheat cv Bobwhite. Four independent transgenic lines containing FgTRI101 were identified. Gene expression studies showed that FgTRI101 was highly expressed in wheat leaf and spike tissues in the transgenic line FgTri101-1606. The seedlings of two FgTri101 transgenic wheat lines (FgTri101-1606 and 1651) grew significantly longer roots than the controls on media containing 5 µg/mL DON; however, the 3-ADON conversion and excretion was detected inconsistently in the seedlings of FgTri101-1606. Further analyses did not detect 3-ADON or other possible DON-related products in FgTri101-1606 seedlings after adding deuterium-labeled DON into the growth media. FgTri101-transgenic wheat plants showed significantly enhanced FHB resistance and lower DON content after they were infected with F. graminearum, but 3-ADON was not detected. Our study suggests that it is promising to utilize FgTRI101, a gene that the fungus uses for self-protection, for managing FHB and mycotoxin in wheat production.
摘要：
禾谷镰刀菌,镰刀菌枯萎病(FHB)的病原体，产生各种霉菌毒素，污染小麦谷物，并在人类和动物中引起严重的健康问题。脱氧雪腐镰刀菌烯醇（DON）是在受污染的谷物中发现的最常见的单端孢菌烯。我们先前的研究表明，表达拟南芥的禾谷草丝霉3-O-乙酰转移酶（FgTRI101）将DON转化为3-乙酰脱氧雪腐镰刀菌烯醇（3-ADON），并将其排泄到拟南芥细胞外。为了确定小麦是否可以转化和排泄3-ADON并减少FHB和DON污染，克隆了FgTRI101并将其引入到小麦cvBobwhite中。鉴定了含有FgTRI101的四个独立的转基因品系。基因表达研究表明，FgTRI101在转基因品系FgTri101-1606的小麦叶片和穗部组织中高表达。在含有5µg/mLDON的培养基上，两个FgTri101转基因小麦品系（FgTri101-1606和1651）的幼苗的根比对照长得多；但是，在FgTri101-1606的幼苗中不一致地检测到3-ADON转化和排泄。在将氘标记的DON添加到生长培养基中之后,进一步的分析在FgTri101-1606幼苗中未检测到3-ADON或其他可能的DON相关产物。FgTri101转基因小麦植株在感染禾谷草后显示出显着增强的FHB抗性和较低的DON含量，但未检测到3-ADON。我们的研究表明，利用真菌用于自我保护的基因FgTRI101是有希望的，用于管理小麦生产中的FHB和霉菌毒素。
