skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


Title: A cryopreservation method to recover laboratory- and field-derived bacterial communities from mosquito larval habitats
Mosquitoes develop in a wide range of aquatic habitats containing highly diverse and variable bacterial communities that shape both larval and adult traits, including the capacity of adult females of some mosquito species to transmit disease-causing organisms to humans. However, while most mosquito studies control for host genotype and environmental conditions, the impact of microbiota variation on phenotypic outcomes of mosquitoes is often unaccounted for. The inability to conduct reproducible intra- and inter-laboratory studies of mosquito-microbiota interactions has also greatly limited our ability to identify microbial targets for mosquito-borne disease control. Here, we developed an approach to isolate and cryopreserve bacterial communities derived from lab and field-based larval rearing environments of the yellow fever mosquito Aedes aegypti –a primary vector of dengue, Zika, and chikungunya viruses. We then validated the use of our approach to generate experimental microcosms colonized by standardized lab- and field-derived bacterial communities. Our results overall reveal minimal effects of cryopreservation on the recovery of both lab- and field-derived bacteria when directly compared with isolation from non-cryopreserved fresh material. Our results also reveal improved reproducibility of bacterial communities in replicate microcosms generated using cryopreserved stocks over fresh material. Communities in replicate microcosms further captured the majority of total bacterial diversity present in both lab- and field-based larval environments, although the relative richness of recovered taxa as compared to non-recovered taxa was substantially lower in microcosms containing field-derived bacteria. Altogether, these results provide a critical next step toward the standardization of mosquito studies to include larval rearing environments colonized by defined microbial communities. They also lay the foundation for long-term studies of mosquito-microbe interactions and the identification and manipulation of taxa with potential to reduce mosquito vectorial capacity.  more » « less
Award ID(s):
2019368
PAR ID:
10436626
Author(s) / Creator(s):
; ;
Editor(s):
Bartholomay, Lyric C.
Date Published:
Journal Name:
PLOS Neglected Tropical Diseases
Volume:
17
Issue:
4
ISSN:
1935-2735
Page Range / eLocation ID:
e0011234
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ; ; (, Molecular Ecology)
    ABSTRACT Vector mosquitoes are well‐adapted to habitats in urban areas, including belowground infrastructure such as stormwater systems. As a major source of larval habitat in population centers, control of larval populations in stormwater catch basins is an important tool for control of vector‐borne disease. Larval development and adult phenotypes driving vectorial capacity in mosquitoes are modulated by the larval gut microbiota, which is recruited from the aquatic environment in which larvae develop. Laboratory studies have quantified microbe‐mediated impacts on individual mosquito phenotypes, but more work is needed to characterise how microbiota variation shapes population‐level outcomes. Here, we evaluated the relationship between habitat microbiota variation and mosquito population dynamics by simultaneously characterising microbiota diversity, water quality, and mosquito productivity in a network of stormwater catch basins in the Chicago metropolitan area. High throughput sequencing of 16S rRNA gene amplicons from water samples collected from 60 basins over an entire mosquito breeding season detected highly diverse bacterial communities that varied with measures of water quality and over time. In situ measurements of mosquito abundance in the same basins further varied by microbiota composition and the relative abundance of specific bacterial taxa. Altogether, these results illustrate the importance of habitat microbiota in shaping ecological processes that affect mosquito populations. They also lay the foundation for future studies to characterise the mechanisms by which specific bacterial taxa impact individual and population‐level phenotypes related to mosquito vectorial capacity. 
    more » « less
  2. ; ; ; ; (, mSphere)
    Young, Vincent B. (Ed.)
    ABSTRACT Mosquito larvae encounter diverse assemblages of bacteria (i.e., “microbiota”) and fungi in the aquatic environments that they develop in. However, while a number of studies have addressed the diversity and function of microbiota in mosquito life history, relatively little is known about mosquito-fungus interactions outside several key fungal entomopathogens. In this study, we used high-throughput sequencing of internal transcribed spacer 2 (ITS2) metabarcode markers to provide the first simultaneous characterization of the fungal communities in field-collected Aedes albopictus larvae and their associated aquatic environments. Our results reveal unprecedented variation in fungal communities among adjacent but discrete larval breeding habitats. Our results also reveal a distinct fungal community assembly in the mosquito gut versus other tissues, with gut-associated fungal communities being most similar to those present in the environment where larvae feed. Altogether, our results identify the environment as the dominant factor shaping the fungal community associated with mosquito larvae, with no evidence of environmental filtering by the gut. These results also identify mosquito feeding behavior and fungal mode of nutrition as potential drivers of tissue-specific fungal community assembly after environmental acquisition. IMPORTANCE The Asian tiger mosquito, Aedes albopictus , is the dominant mosquito species in the United States and an important vector of arboviruses of major public health concern. One aspect of mosquito control to curb mosquito-borne diseases has been the use of biological control agents such as fungal entomopathogens. Recent studies also demonstrate the impact of mosquito-associated microbial communities on various mosquito traits, including vector competence. However, while much research attention has been dedicated to understanding the diversity and function of mosquito-associated bacterial communities, relatively little is known about mosquito-associated fungal communities. A better understanding of the factors that drive fungal community diversity and assembly in mosquitoes will be essential for future efforts to target mosquito-associated bacteria and fungi for mosquito and mosquito-borne disease control. 
    more » « less
  3. ; ; ; (, Proceedings of the Royal Society B: Biological Sciences)
    null (Ed.)
    Most species of mosquitoes are detritivores that feed on decaying plant and animal materials in their aquatic environment. Studies of several detritivorous mosquito species indicate that they host relatively low diversity communities of microbes that are acquired from the environment while feeding. Our recent results also indicate that detritivorous species normally require a living gut microbiota to grow beyond the first instar. Less well known is that some mosquitoes, including those belonging to the genus Toxorhynchites , are predators that feed on other species of mosquitoes and nektonic prey. In this study, we asked whether predaceous Toxorhynchites amboinensis larvae still require living microbes in their gut in order to develop. Using the detritivorous mosquito Aedes aegypti as prey, we found that T. amboinensis larvae harbour bacterial communities that are highly similar to that of their prey. Functional assays showed that T. amboinensis first instars provided axenic (i.e. bacteria-free) prey failed to develop, while two bacterial species present in gnotobiotic (i.e. colonized by one or more known bacterial species) prey successfully colonized the T. amboinensis gut and rescued development. Axenic T. amboinensis larvae also displayed defects in growth consistent with previously identified roles for microbe-mediated gut hypoxia in nutrient acquisition and assimilation in A. aegypti. Collectively, these results support a conserved role for gut microbes in regulating the development of mosquitoes with different feeding strategies. 
    more » « less
  4. ; (, Animal Microbiome)
    Abstract BackgroundThe leaves of carnivorous pitcher plants harbor diverse communities of inquiline species, including bacteria and larvae of the pitcher plant mosquito (Wyeomyia smithii), which aid the plant by processing captured prey. Despite the growing appreciation for this microecosystem as a tractable model in which to study food web dynamics and the moniker ofW. smithiias a ‘keystone predator’, very little is known about microbiota acquisition and assembly inW. smithiimosquitoes or the impacts ofW. smithii-microbiota interactions on mosquito and/or plant fitness. ResultsIn this study, we used high throughput sequencing of bacterial 16S rRNA gene amplicons to characterize and compare microbiota diversity in field- and laboratory-derivedW. smithiilarvae. We then conducted controlled experiments in the laboratory to better understand the factors shaping microbiota acquisition and persistence across theW. smithiilife cycle. Methods were also developed to produce axenic (microbiota-free)W. smithiilarvae that can be selectively recolonized with one or more known bacterial species in order to study microbiota function. Our results support a dominant role for the pitcher environment in shaping microbiota diversity inW. smithiilarvae, while also indicating that pitcher-associated microbiota can persist in and be dispersed by adultW. smithiimosquitoes. We also demonstrate the successful generation of axenicW. smithiilarvae and report variable fitness outcomes in gnotobiotic larvae monocolonized by individual bacterial isolates derived from naturally occurring pitchers in the field. ConclusionsThis study provides the first information on microbiota acquisition and assembly inW. smithiimosquitoes. This study also provides the first evidence for successful microbiota manipulation in this species. Altogether, our results highlight the value of such methods for studying host-microbiota interactions and lay the foundation for future studies to understand howW. smithii-microbiota interactions shape the structure and stability of this important model ecosystem. 
    more » « less
  5. ; ; ; (, Journal of Medical Entomology)
    Abstract Diapause is a hormonally driven response which is triggered by environmental cues that signal impending adverse conditions and prompts metabolic, developmental, and behavioral changes to allow survival until the return of favorable conditions. Microbial symbionts have been shown to influence the metabolism, development, and behavior of their host organisms, all of which are common diapause-associated characteristics. Surveys of bacterial components in relation to diapause have been examined in few systems, of which the species are usually inactive during dormancy, such as eggs or pupae. This is specifically intriguing as adult female diapause in Culex pipiens (Diptera: Culicidae) can last between 4 and 7 mo and females remain mobile within their hibernacula. Furthermore, it is unknown how microbiota changes associated with prolonged dormancy are different between the lab and field for insect systems. This study aims to characterize how the microbiota of C. pipiens changes throughout diapause under both field and lab settings when provided identical food and water resources. Based on these studies, C. pipiens microbiota shifts as diapause progresses and there are considerable differences between field and lab individuals even when provided the same carbohydrate and water sources. Specific bacterial communities have more association with different periods of diapause, field and lab rearing conditions, and nutritional reserve levels. These studies highlight that diapausing mosquito microbiota studies ideally should occur in field mesocosms and at multiple locations, to increase applicability to wild C. pipiens as prolonged exposure to artificial rearing conditions could impact metrics related to diapause-microbiome interactions. Additionally, these findings suggest that it would be worthwhile to establish if the microbiota shift during diapause impacts host physiology and whether this shift is critical to diapause success. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email