Vallejo Gustavo Adolfo, Guhl Felipe, Carranza Julio César, Moreno Jaime, Triana Omar, Grisard Edmundo Carlos
Laboratorio de Investigaciones en Parasitología Tropical, Universidad del Tolima, Ibagué, Colombia.
Infect Genet Evol. 2003 May;3(1):39-45. doi: 10.1016/s1567-1348(02)00150-8.
Trypanosoma rangeli are kinetoplastid protozoa which have been largely recognized and defined in several Latin American countries in relation to T. cruzi, because the two trypanosome species are frequently found in mixed infections in triatominae vectors, humans and a variety of wild and domestic mammals. We report the molecular characterization of 18 T. rangeli strains isolated from the salivary glands of naturally infected Rhodnius colombiensis, R. pallescens and R. prolixus by using two independent set of molecular markers. kDNA and mini-exon amplification indicated dimorphism within both DNA sequences: KP1, KP2 and KP3 or KP2 and KP3 products for kDNA mini-circles and 380 or 340bp products for the mini-exon. One of two associations was observed within individual strains: KP1, KP2 and KP3 kDNA products with the 340bp mini-exon product and the KP2 and KP3 kDNA products with the 380bp mini-exon product. Independent mitochondrial and nuclear molecular markers showed a clear division of T. rangeli into two major phylogenetic groups associated with specific vectors in Colombia and in other Latin America countries. These results support either clonal evolution or speciation in T. rangeli populations, probably derived as a secondary adaptation to their parasitic condition in triatomine vectors.
克氏锥虫是动基体原生动物，在几个拉丁美洲国家，相对于克氏锥虫，它已得到广泛的认识和定义，因为这两种锥虫经常在锥蝽媒介、人类以及各种野生和家养哺乳动物的混合感染中被发现。我们报告了从自然感染的哥伦比亚红猎蝽、苍白猎蝽和长红猎蝽唾液腺中分离出的18株克氏锥虫的分子特征，使用了两组独立的分子标记。kDNA和小外显子扩增表明两个DNA序列内存在二态性：kDNA小环的KP1、KP2和KP3或KP2和KP3产物，以及小外显子的380或340bp产物。在单个菌株中观察到两种关联之一：KP1、KP2和KP3 kDNA产物与340bp小外显子产物，以及KP2和KP3 kDNA产物与380bp小外显子产物。独立的线粒体和核分子标记显示，克氏锥虫明显分为两个主要的系统发育组，与哥伦比亚和其他拉丁美洲国家的特定媒介相关。这些结果支持了克氏锥虫种群中的克隆进化或物种形成，这可能是作为对其在锥蝽媒介中寄生条件的二次适应而产生的。
