CHARACTERIZATION OF A CONSERVED EXTRACHROMOSOMAL ELEMENT ISOLATED FROM THE AVIAN MALARIAL PARASITE PLASMODIUM-GALLINACEUM
CHARACTERIZATION OF A CONSERVED EXTRACHROMOSOMAL ELEMENT ISOLATED FROM THE AVIAN MALARIAL PARASITE PLASMODIUM-GALLINACEUM
复制标题
DOI：
10.1128/mcb.9.9.3621
复制
发表时间：
1989-09-01
影响因子：
5.3
通讯作者：
WIRTH, DF
中科院分区：
文献类型：
--
作者：
JOSEPH, JT;ALDRITT, SM;WIRTH, DF
我们已经从禽疟原虫中鉴定出一个保守的、重复的、高度转录的DNA元素。该元素在这种寄生虫的受精卵和无性血阶段都产生了多个转录本。结果发现，该基因在所有5种被测试的疟疾物种中高度保守，并与顶端复合体门的其他成员（包括巴贝虫属、艾美耳虫属、弓形虫属和伊氏菌属）进行了较低的杂交。该元素的拷贝数约为15，具有一个循环排列的限制性映射，重复单位长度约为6.2千碱基。利用蔗糖梯度和琼脂糖凝胶可以将其从主基因组DNA中分离出来，并在脉冲场凝胶上从已识别的疟原虫染色体中分离出来。在随附的论文中（S. M. Aldritt， J. T. Joseph和D. F. Wirth, Mol. Cell）。Biol. 9:3614-3620, 1989)，有证据表明该元素含有细胞色素b蛋白的线粒体基因和一个大rRNA片段。我们假设这个元素是属于顶复合体门的专性寄生虫线粒体中的一个插曲。
We have identified a conserved, repeated, and highly transcribed DNA element from the avian malarial parasite Plasmodium gallinaceum. The element produced multiple transcripts in both zygotes and asexual blood stages of this parasite. It was found to be highly conserved in all of five malarial species tested and hybridized at reduced stringency to other members of the phylum Apicomplexa, including the genera Babesia, Eimeria, Toxoplasma, and Theileria. The copy number of the element was about 15, and it had a circularly permuted restriction map with a repeat unit length of about 6.2 kilobases. It could be separated from the main genomic DNA by using sucrose gradients and agarose gels, and it migrated separately from the recognized Plasmodium chromosomes on pulse-field gels. In the accompanying paper (S. M. Aldritt, J. T. Joseph, and D. F. Wirth, Mol. Cell. Biol. 9:3614-3620, 1989), evidence is presented that element contains the mitochondrial genes for the protein cytochrome b and a fragment of the large rRNA. We postulate that this element is an episome in the mitochondria of the obligate parasites belonging to the phylum Apicomplexa.