Musale Pankaj, Khilari Ajinkya, Gade Rohini, Dhanikachalam Velu, Jadhav Santoshkumar, Bajpai Manali, Turakani Bhagya, Joshi Akshay, Prajapati Amar, Srivastava Anand, Swaminathan Marimuthu, Joshi Sachin, Shanmugam Dhanasekaran
Biochemical Sciences Division, CSIR- National Chemical Laboratory, Pune, Maharashtra, India.
Animal Breeding and Genetics Department, BAIF Development Research Foundation, Uruli Kanchan, Pune, Maharashtra, India.
PLoS One. 2025 Jul 18;20(7):e0326243. doi: 10.1371/journal.pone.0326243. eCollection 2025.
Buparvaquone (BPQ) is used for the treatment of bovine theileriosis, a tickborne disease caused by parasites of the Theileria genus. Studies on T. annulata have linked the mechanism of BPQ resistance predominantly to genetic variations in the parasite cytochrome b (cytb) gene. In addition, cryptic mechanisms of resistance involving the parasite peptidyl-prolyl isomerase (pin1) and dihydroorotate dehydrogenase (dhodh) genes require assessment. In India, where bovine theileriosis is endemic, and BPQ is widely used for treatment, it is necessary to establish the prevalence of genetic variations linked to BPQ resistance. In this study, multiplexed PCR amplification and nanopore sequencing method was used for genotyping the complete gene loci of the three target genes. Analysis of 454 T. annulata field samples collected from seven different states of India revealed the presence of previously reported BPQ resistance associated variations S129G, A146T and P253S in cytb gene and A53P in pin1 gene. The A146T and I203V variations in cytb were found to be prevalent and mostly co-occurring, and their role in BPQ resistance needs further evaluation. This study has revealed the presence of previously reported BPQ resistance-linked mutations in cytb and pin1 genes in T. annulata infecting dairy cattle in India and establishes an Oxford nanopore sequencing method suitable for large-scale surveillance of genetic variation in Theileria parasites from field samples.
布帕伐醌（BPQ）用于治疗牛泰勒虫病，这是一种由泰勒虫属寄生虫引起的蜱传疾病。对环形泰勒虫的研究表明，BPQ耐药机制主要与寄生虫细胞色素b（cytb）基因的遗传变异有关。此外，涉及寄生虫肽基脯氨酰异构酶（pin1）和二氢乳清酸脱氢酶（dhodh）基因的潜在耐药机制也需要评估。在牛泰勒虫病流行且BPQ广泛用于治疗的印度，有必要确定与BPQ耐药相关的遗传变异的流行情况。在本研究中，采用多重PCR扩增和纳米孔测序方法对三个靶基因的完整基因座进行基因分型。对从印度七个不同邦采集的454份环形泰勒虫野外样本的分析显示，在cytb基因中存在先前报道的与BPQ耐药相关的变异S129G、A146T和P253S，在pin1基因中存在A53P变异。发现cytb基因中的A146T和I203V变异普遍存在且大多同时出现，它们在BPQ耐药中的作用需要进一步评估。本研究揭示了在印度感染奶牛的环形泰勒虫的cytb和pin1基因中存在先前报道的与BPQ耐药相关的突变，并建立了一种适用于大规模监测野外样本中泰勒虫寄生虫遗传变异的牛津纳米孔测序方法。
