Biology subjects

Villegas, L. E. M.

Publications and source records attributed to Villegas, L. E. M..

2 recordsLinked to original sources

bioRxiv2024

Are you my mother?: When host genetics and gut microbiota tell different phylogenetic stories in the Africanized honey bee hybrid (Apis mellifera scutellata x sspp.)

Africanized honey bees (Apis mellifera scutellata x sspp.) originated in Brazil through the crossbreeding of African (A. mellifera scutellata) and European (A. mellifera sspp.) honey bee subspecies. African genes came to dominate in these hybrid honey bees over time. Gut microbiota co-evolve with their hosts and generally reflect host phylogeny. To examine if this was true in Africanized honey bee hybrids, we compared the gut microbiota (16S rRNA) of 3 honey bee subspecies: African, European, and Africanized honey bees. Publicly available sequencing data from five honey bee studies were downloaded from NCBI. European bee samples (n=42) came from United Kingdom, Switzerland, and United States. African bee samples (n=82) came from Kenya. Africanized bee samples (n=10) came from Brazil. Unexpectedly, Africanized honey bee gut microbiota was far more similar to European bees than to African bees despite the closer host genetic relationship between African and Africanized bees. All three subspecies shared similar relative abundances of core taxa. We posit that the similarity in gut microbiota between Africanized and European honey bees arose from the nature of the crossbreeding, and the social / environmental transmission of gut microbiota within hives. Namely, African queens took over European hives. However, the hybrid offspring acquired their gut microbiota from European nurse bees and European hive materials, resulting in the stable transmission of European gut microbiota across generations. Our results provide an intriguing insight into the potential ecological, social, and environmental factors that shape the gut microbiota of the Africanized honey bee hybrid. ImportanceAfricanized honey bee hybrids originated in Brazil through the crossbreeding of African and European honey bee subspecies. In this study, we examined the gut microbiota of all 3 honey bee subspecies (African, European, Africanized). A few core microbiota were shared across all subspecies. Interestingly, while African honey bee genes dominated in the Africanized honey bee hybrids, their gut microbial composition was most similar to European bees. This is likely related to the way these bees were crossbred - with African queens taking over European hives, while gut microbial inoculation of hybrids came from European nurse bees and European hive matierals. Gut microbiota are critical to honey bee health, and studying the gut microbiota of closely related honey bee subspecies helps understand the factors that influence gut microbial composition. This is important for our broader understanding of honey bee health, conservation, and evolution.

microbiology↗

bioRxiv2023

The microbiota of Amblyomma americanum reflects known westward expansion.

AbstractAmblyomma americanum, a known vector of multiple tick-borne pathogens, has expanded its geographic distribution across the United States in the past decades. Tick microbiomes may play a role shaping their hosts life history and vectorial capacity. Bacterial communities associated with A. americanum may reflect, or enable, geographic expansion and studying the microbiota will improve understanding of tick- borne disease ecology. We examined the microbiota structure of 189 adult ticks collected in four regions encompassing their historical and current geographic distribution. Both geographic region of origin and sex were significant predictors of alpha diversity. As in other tick models, within-sample diversity was low and uneven given the presence of dominant endosymbionts. Beta diversity analyses revealed that bacterial profiles of ticks of both sexes collected in the West were significantly different from those of the Historic range. Biomarkers were identified for all regions except the historical range. In addition, Bray-Curtis dissimilarities overall increased with distance between sites. Relative quantification of ecological processes showed that, for females and males, respectively, drift and dispersal limitation were the primary drivers of community assembly. Collectively, our findings highlight how microbiota structural variance discriminates the western-expanded populations of A. americanum ticks from the Historical range. Spatial autocorrelation, and particularly the detection of non- selective ecological processes, are indicative of geographic isolation. Our conclusions demonstrate the value of synergistic analysis of biogeographic and microbial ecology data in investigating range expansion in A. americanum and potentially other tick vectors as well. ImportanceThe incidence of tick-borne diseases is on the rise worldwide, including in the United States. This increase in cases is in large part due to the geographic expansion of tick vectors. Among them is the Lone Star tick, Amblyomma americanum, and understanding the factors driving its recent expansion is important for risk assessment and tick population control. Climate change and human activities have previously been posited to be main driving forces for their expansion. New sources of relevant biological data can further our understanding of this phenomenon. Microbial communities associated with ticks include bacteria that affect pathogen transmission and tick behaviors. Here, we investigated whether bacterial community and geographic location data could be combined to better understand the expansion of A. americanum populations. Its not clear whether differences in the microbiota are reflective of or facilitating expansion, but our findings suggest this approach is promising and warrants further investigation.

ecology↗