Zarlenga D S, Hoberg E P, Stringfellow F, Lichtenfels J R
U.S. Department of Agriculture, ARS, Immunology and Disease Resistance Laboratory, Beltsville, Maryland 20705, USA.
J Parasitol. 1998 Aug;84(4):806-12.
The first internal transcribed spacer DNA (ITS-1) (rDNA) and the mitochondrial (mt) DNA-derived cytochrome oxidase I gene (COX-1) were enzymatically amplified, cloned and sequenced from 6 nominal species of Ostertagiinae as well as Haemonchus contortus and Haemonchus placei. The portion of the COX-1 gene analyzed was 393 base pairs (bp) in length and contained 33 within species polymorphic base changes at 28 synonymous sites. The ITS-1 rDNA consensus sequences ranged from 392 bp (Ostertagia ostertagi/Ostertagia lyrata, Teladorsagia circumcincta) to 404 bp (H. contortus, H. placei). These data were used both in a distance analysis to assess the concept of polymorphic species within the genus Ostertagia and in parsimony analysis to assess phylogenetic relationships within a limited group of Ostertagiinae. Pairwise similarity scores of both ITS-1 and COX-1 data showed the highest number of conserved sites between the proposed dimorphic species of Ostertagia. The level of similarity was lower in the COX-1 data due to the high number of synonymous base changes. Analysis by maximum parsimony of the same data did not refute O. ostertagi/O. lyrata and Ostertagia mossil/Ostertagia dikmansi as dimorphic species and supported monophyly of these ostertagiines relative to representatives of the haemonchine outgroup. In the single most parsimonious tree from ITS-1 rDNA data, a subclade of Ostertagia spp. included forms possessing parallel synlophes and long esophageal valves that typically occur in cervid hosts.
从6个奥斯特他属（Ostertagiinae）的标称物种以及捻转血矛线虫（Haemonchus contortus）和长刺血矛线虫（Haemonchus placei）中，通过酶促扩增、克隆和测序，获得了第一内部转录间隔区DNA（ITS-1）（核糖体DNA）和线粒体（mt）DNA来源的细胞色素氧化酶I基因（COX-1）。所分析的COX-1基因部分长度为393个碱基对（bp），在28个同义位点包含33个种内多态性碱基变化。ITS-1核糖体DNA共有序列长度从392 bp（奥氏奥斯特他线虫/里拉奥斯特他线虫、环形泰勒虫）到404 bp（捻转血矛线虫、长刺血矛线虫）不等。这些数据既用于距离分析以评估奥斯特他属内多态性物种的概念，也用于简约分析以评估有限的奥斯特他亚科组内的系统发育关系。ITS-1和COX-1数据的成对相似性得分显示，在奥斯特他属提议的二态物种之间，保守位点数量最多。由于同义碱基变化数量较多，COX-1数据中的相似性水平较低。对相同数据进行最大简约分析，并未反驳奥氏奥斯特他线虫/里拉奥斯特他线虫以及莫氏奥斯特他线虫/迪氏奥斯特他线虫为二态物种的观点，并支持这些奥斯特他亚科相对于血矛线虫外群代表的单系性。在来自ITS-1核糖体DNA数据的单一最简约树中，奥斯特他属物种的一个亚分支包括具有平行细纹和长食管瓣的形态，这些形态通常出现在鹿类宿主中。
