Genetic diversity of the DBLα region in Plasmodium falciparum var genes among Asia-Pacific isolates
Genetic diversity of the DBLα region in Plasmodium falciparum var genes among Asia-Pacific isolates
复制标题
DOI：
10.1016/s0166-6851(01)00443-1
复制
发表时间：
2002-03-01
影响因子：
1.5
通讯作者：
Cheng, Q
中科院分区：
文献类型：
--
作者：
Fowler, EV;Peters, JM;Cheng, Q
在恶性疟原虫中，一个高度多态性的多拷贝基因家族，var。编码变异表面抗原恶性疟原虫红细胞膜蛋白1（PtTEMP 1），其在细胞粘附和免疫逃避中具有重要作用。使用先前描述的car第一个Duffy结合样结构域（DBL alpha）的通用PCR引物，我们分析了Dd 2的DBL alpha谱系（最初来自泰国）和来自所罗门群岛（n = 4）、菲律宾（n = 2）的8个分离株。巴布亚新几内亚（n = 1）和非洲（n = 1）。我们在这些分离株中发现了15-32种独特的DBL α序列类型，估计可检测的DBL α库大小范围为每个基因组33-38至52-57个拷贝。我们的数据表明，var基因库通常由每个基因组40-50个拷贝组成。18个DBL α序列出现在一个以上的亚太分离株中，任何两个分离株之间共享的序列数量范围为0至6（平均值= 2.0 +/- 1.6）。在氨基酸水平上，分离物间DBL α序列相似性为45.2 ± 7.1%~ 50.2 ± 6.9%，分离物间DBL α序列相似性差异不显著（P > 0.1）。与已发表序列的比较也显示来自不同地区的DBL α序列之间几乎没有重叠。高DBL α序列的多样性和最小的重叠，这些菌株之间的全球var基因库是巨大的，并可能被选择的主机的保护性免疫反应的焦油基因产物，PfEMP 1。皇冠版权所有（C）2002出版的爱思唯尔科学B. V.保留所有权利。
In Plasmodium falciparum a highly polymorphic multi-copy gene family, var. encodes the variant surface antigen P. falciparum erythrocyte membrane protein 1 (PtTEMP1), which has an important role in cytoadherence and immune evasion, Using previously described universal PCR primers for the first Duffy binding-like domain (DBLalpha) of car we analysed the DBLalpha repertoires of Dd2 (originally from Thailand) and eight isolates front the Solomon Islands (n = 4), Philippines (n = 2). Papua New Guinea (n = 1) and Africa (n = 1). We found 15-32 unique DBLalpha sequence types among these isolates and estimated detectable DBLalpha repertoire sizes ranging from 33-38 to 52-57 copies per genome. Our data suggest that var gene repertoires generally consist of 40-50 copies per genome. Eighteen DBLalpha sequences appeared in more than one Asia-Pacific isolate kith the number of sequences shared between any two isolates ranging front 0 to 6 (mean = 2.0 +/- 1.6). At the amino acid level DBLalpha sequence similarity within isolates ranged from 45.2 +/- 7.1 to 50.2 +/- 6.9%, and was not significantly different front the DBLalpha amino acid sequence similarity among isolates (P > 0.1). Comparisons with published sequences also revealed little overlap among DBLalpha sequences from different regions. High DBLalpha sequence diversity and minimal overlap among these isolates suggest that the global var gene repertoire is immense, and may potentially be selected for by the host's protective immune response to the tar gene products, PfEMP1. Crown Copyright (C) 2002 Published by Elsevier Science B.V. All rights reserved.