|GALL, CORY - Washington State University|
|MAGORI, KRISZTIAN - Eastern Washington University|
|BRAYTON, KELLY - Washington State University|
Submitted to: Microbiome
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/24/2017
Publication Date: 10/4/2017
Citation: Gall, C.A., Scoles, G.A., Magori, K., Mason, K.L., Brayton, K.A. 2017. Laboratory colonization stabilizes the naturally dynamic microbiome composition of field collected dermacentor andersoni ticks. BMC Microbiome. 5:133.
Interpretive Summary: A large number of emerging infectious diseases are transmitted by arthropods, primarily mosquitoes and ticks. Although ticks can carry pathogenic microorganisms, non-pathogenic microbes make up most of the tick’s microbial community. Current tick microbiome research has had a focus on discovery and description of the microbial communities in ticks, with only a few studies investigating the ecology of the bacterial microbiome of ticks, specifically with regard to its function and response to changing conditions. The goal of this study was to characterize the bacterial microbiome of a vector of human and animal pathogens, the Rocky Mountain wood tick, under different conditions of time and space. The results from this project confirm that the microbiome of wood tick populations differ based on the tick tissue (midgut vs. salivary glands) as well as the location the tick population was collected from (Burns, Oregon vs. Lake Como, Montana). Additionally, we analyzed microbiome composition over three generations of colonization in the lab, and we found that although it changes with colonization the microbiome of lab populations was dependent on where the tick populations were originally collected, suggesting that the initial microbiome influences the outcome of lab colonization. Furthermore, our study showed that the proportion and composition of microbes making up the microbiomes of laboratory-reared populations were different from those of their respective field populations. We demonstrated that the bacterial microbiome of the wood tick was dynamic through time and unique to tick tissue type and geographic location. These results provide evidence that an understanding of the ecology and behavior of the bacterial microbiome is vital, and needs to be further investigated if we are to employ manipulation of the microbiome as a means of tick-borne pathogen control.
Technical Abstract: Nearly a quarter of emerging infectious diseases in the last century were transmitted by arthropods. Although ticks and insects can carry pathogenic microorganisms, non-pathogenic microbes make up the majority of the microbial community. Currently, the majority of tick microbiome research has had a focus on discovery with descriptive outcomes. Additionally, only a few studies have analyzed the ecology and behavior of the bacterial microbiome of ticks. The goal of this analysis was to characterize the bacterial microbiome of Dermacentor andersoni ticks under different ecological factors, focusing on time and space. In this study, the microbiome of D. andersoni was tissue- and spatial-specific; however, generational variation was dependent on field site. Furthermore, our study showed that the microbiomes of laboratory-reared populations were not representative of the respective field population. We demonstrated that the bacterial microbiome of D. andersoni was dynamic and unique to tick tissue and geographic location. These results provide evidence that ecological variation is a vital component to the complexity of the bacterial microbiome and needs to be further investigated in order to employ microbiome manipulation as a source of pathogen acquisition and transmission interference.