Deom Carl Michael, Alabady Magdy S, Yang Li
Department of Plant Pathology, University of Georgia, Athens, GA, USA.
Department of Plant Biology, University of Georgia, Athens, GA, USA.
BMC Genomics. 2021 Mar 2;22(1):147. doi: 10.1186/s12864-021-07455-y.
The Beet curly top virus C4 oncoprotein is a pathogenic determinant capable of inducing extensive developmental abnormalities. No studies to date have investigated how the transcriptional profiles differ between plants expressing or not expressing the C4 oncoprotein.
We investigated early transcriptional changes in Arabidopsis associated with expression of the Beet curly top virus C4 protein that represent initial events in pathogenesis via a comparative transcriptional analysis of mRNAs and small RNAs. We identified 48 and 94 differentially expressed genes at 6- and 12-h post-induction versus control plants. These early time points were selected to focus on direct regulatory effects of C4 expression. Since previous evidence suggested that the C4 protein regulated the brassinosteroid (BR)-signaling pathway, differentially expressed genes could be divided into two groups: those responsive to alterations in the BR-signaling pathway and those uniquely responsive to C4. Early transcriptional changes that disrupted hormone homeostasis, 18 and 19 differentially expressed genes at both 6- and 12-hpi, respectively, were responsive to C4-induced regulation of the BR-signaling pathway. Other C4-induced differentially expressed genes appeared independent of the BR-signaling pathway at 12-hpi, including changes that could alter cell development (4 genes), cell wall homeostasis (5 genes), redox homeostasis (11 genes) and lipid transport (4 genes). Minimal effects were observed on expression of small RNAs.
This work identifies initial events in genetic regulation induced by a geminivirus C4 oncoprotein. We provide evidence suggesting the C4 protein regulates multiple regulatory pathways and provides valuable insights into the role of the C4 protein in regulating initial events in pathogenesis.
甜菜曲顶病毒C4癌蛋白是一种致病决定因素，能够诱导广泛的发育异常。迄今为止，尚无研究调查表达或不表达C4癌蛋白的植物之间转录谱有何不同。
我们通过对mRNA和小RNA的比较转录分析，研究了拟南芥中与甜菜曲顶病毒C4蛋白表达相关的早期转录变化，这些变化代表了发病机制中的初始事件。与对照植物相比，我们在诱导后6小时和12小时分别鉴定出48个和94个差异表达基因。选择这些早期时间点以关注C4表达的直接调节作用。由于先前的证据表明C4蛋白调节油菜素类固醇（BR）信号通路，差异表达基因可分为两组：对BR信号通路改变有反应的基因和对C4有独特反应的基因。在6小时和12小时分别有18个和19个差异表达基因破坏了激素稳态，这些基因对C4诱导的BR信号通路调节有反应。在感染后12小时，其他C4诱导的差异表达基因似乎独立于BR信号通路，包括可能改变细胞发育（4个基因）、细胞壁稳态（5个基因）、氧化还原稳态（11个基因）和脂质转运（4个基因）的变化。观察到小RNA表达的影响最小。
这项工作确定了双生病毒C4癌蛋白诱导的基因调控中的初始事件。我们提供的证据表明C4蛋白调节多种调控途径，并为C4蛋白在调节发病机制初始事件中的作用提供了有价值的见解。
