Ramm Crystal, Wachholtz Michael, Amundsen Keenan, Donze Teresa, Heng-Moss Tiffany, Twigg Paul, Palmer Nathan A, Sarath Gautam, Baxendale Fred
Department of Entomology, University of Nebraska, Lincoln, NE 68583.
Department of Biology, University of Nebraska, Omaha, NE 68182.
J Econ Entomol. 2015 Jun;108(3):1354-62. doi: 10.1093/jee/tov067. Epub 2015 Mar 31.
Understanding plant resistance mechanisms at a molecular level would provide valuable insights into the biological pathways impacted by insect feeding, and help explain specific plant tolerance mechanisms. As a first step in this process, we conducted next-generation sequencing using RNA extracted from chinch bug-tolerant and -susceptible buffalograss genotypes at 7 and 14 d after chinch bug feeding. Sequence descriptions and gene ontology terms were assigned to 1,701 differentially expressed genes. Defense-related transcripts were differentially expressed within the chinch bug-tolerant buffalograss, Prestige, and susceptible buffalograss, 378. Interestingly, four peroxidase transcripts had higher basal expression in tolerant control plants compared with susceptible control plants. Defense-related transcripts, including two peroxidase genes, two catalase genes, several cytochrome P450 transcripts, a glutathione s-transferase, and a WRKY gene were upregulated within the Prestige transcriptome in response to chinch bug feeding. The majority of observed transcripts with oxidoreductase activity, including nine peroxidase genes and a catalase gene, were downregulated in 378 in response to initial chinch bug feeding. The observed difference in transcript expression between these two buffalograss genotypes provides insight into the mechanism(s) of resistance, specifically buffalograss tolerance to chinch bug feeding.
在分子水平上理解植物抗性机制将为受昆虫取食影响的生物学途径提供有价值的见解，并有助于解释特定的植物耐受机制。作为这一过程的第一步，我们在牧草盲蝽取食后7天和14天，使用从耐牧草盲蝽和感牧草盲蝽的野牛草基因型中提取的RNA进行了下一代测序。序列描述和基因本体术语被分配给1701个差异表达基因。在耐牧草盲蝽的野牛草品种Prestige和感牧草盲蝽的378品种中，与防御相关的转录本存在差异表达。有趣的是，与感虫对照植株相比，四个过氧化物酶转录本在耐虫对照植株中的基础表达更高。在Prestige转录组中，包括两个过氧化物酶基因、两个过氧化氢酶基因、几个细胞色素P450转录本、一个谷胱甘肽S-转移酶和一个WRKY基因在内的与防御相关的转录本，在牧草盲蝽取食后上调。在378品种中，大多数具有氧化还原酶活性的观察到的转录本，包括九个过氧化物酶基因和一个过氧化氢酶基因，在牧草盲蝽初次取食后下调。这两种野牛草基因型之间观察到的转录本表达差异为抗性机制，特别是野牛草对牧草盲蝽取食的耐受性机制提供了见解。
