The investigation of methylation status in relation to the presence of Borrelia burgdorferi in Ixodes scapularis (black-legged tick)

Abstract

Ticks, arthropod carriers of Borrelia burgdorferi, and other bacterial, viral, and protozoan pathogens are largely responsible for the spread of Lyme disease. The increasing prevalence of Lyme disease globally has led to further research into the mechanisms and causes of the disease and the spread of infection. Underlying mechanisms of behavioral and physical modifications of ticks, specifically Ixodes scapularis that result in increased survival due to the tick infection status are not fully understood. The bacterium Anaplasma phagocytophilum is recognized to alter the physiology of ticks through epigenetics mechanisms; similarly, we postulated that changes in DNA methylation may also result from the interaction of Ixodes scapularis and Borrelia burgdorferi. This study seeks to determine if the methylation status in tandem repeat regions Ixodes scapularis repeats (ISRs) differs between Borrelia burgdorferi infected and uninfected Ixodes scapularis ticks. DNA was extracted from female Ixodes scapularis ticks, both infected and not, as verified by nested PCR and used for Methylated-DNA immunoprecipitation followed by quantitative PCR.Primers were designed to target ISR regions 1-3. The results suggest that there are no differences in methylated DNA between infection statuses, however, the amount of methylated DNA does differ between ISR primer regions. This study provides a basis for future epigenetic studies on the epigenetic interactions between pathogens and possible phenotypic changes in their arthropod vectors.