Coates B S, Sumerford D V, Hellmich R L, Lewis L C
USDA-ARS, Corn Insect and Crop Genetics Research Unit, Genetics Laboratory, Iowa State University, Ames, Iowa 50011, USA.
Insect Mol Biol. 2008 Dec;17(6):607-20. doi: 10.1111/j.1365-2583.2008.00833.x.
Genes expressed in lepidopteran midgut tissues are involved in digestion and Bacillus thuringiensis (Bt) toxin resistance traits. Five hundred and thirty five unique transcripts were annotated from 1745 high quality O. nubilalis larval midgut expressed sequence tags (ESTs). Full-length cDNA sequence of 12 putative serine proteinase genes and 3 partial O. nubilalis aminopeptidase N protein genes, apn1, apn3, and apn4, were obtained, and genes may have roles in plant feeding and Bt toxin resistance traits of Ostrinia larvae. The EST library was not normalized and insert frequencies reflect transcript levels under the initial treatment conditions and redundancy of inserts from highly expressed transcripts allowed prediction of putative single nucleotide polymorphisms (SNPs). Ten di-, tri- or tetranucleotide repeat unit microsatellite loci were identified, and minisatellite repeats were observed within the C-termini of two encoded serine proteinases. Molecular markers showed polymorphism at 28 SNP loci and one microsatellite locus, and Mendelian inheritance indicated that markers were applicable to genome mapping applications. This O. nubilalis larval midgut EST collection is a resource for gene discovery, expression information, and allelic variation for use in genetic marker development.
在鳞翅目昆虫中肠组织中表达的基因参与消化过程以及对苏云金芽孢杆菌（Bt）毒素的抗性特征。从1745个高质量的欧洲玉米螟幼虫中肠表达序列标签（ESTs）中注释出了535个独特的转录本。获得了12个假定的丝氨酸蛋白酶基因以及3个部分欧洲玉米螟氨肽酶N蛋白基因apn1、apn3和apn4的全长cDNA序列，这些基因可能在欧洲玉米螟幼虫的取食和对Bt毒素的抗性特征中发挥作用。该EST文库未进行标准化处理，插入频率反映了初始处理条件下的转录水平，并且来自高表达转录本的插入片段冗余性使得能够预测假定的单核苷酸多态性（SNPs）。鉴定出了10个二核苷酸、三核苷酸或四核苷酸重复单元的微卫星位点，并且在两个编码的丝氨酸蛋白酶的C末端观察到了小卫星重复序列。分子标记在28个SNP位点和1个微卫星位点表现出多态性，孟德尔遗传表明这些标记适用于基因组图谱绘制应用。这个欧洲玉米螟幼虫中肠EST集合是用于基因发现、表达信息以及等位基因变异的资源，可用于遗传标记开发。
