title: Developmental succession of the microbiome of Culex mosquitoes.
abstract: BACKGROUND
  The native microflora associated with mosquitoes have important roles in mosquito development and vector competence. Sequencing of bacterial V3 region from 16S rRNA genes across the developmental stages of Culex mosquitoes (early and late larval instars, pupae and adults) was used to test the hypothesis that bacteria found in the larval stage of Culex are transstadially transmitted to the adult stage, and to compare the microbiomes of field-collected versus laboratory-reared mosquitoes.
  
  
  RESULTS
  Beta diversity analysis revealed that bacterial community structure differed among three life stages (larvae, pupae and adults) of Culex tarsalis. Although only ~2% of the total number of bacterial OTUs were found in all stages, sequences from these OTUs accounted for nearly 82% of the total bacterial sequences recovered from all stages. Thorsellia (Gammaproteobacteria) was the most abundant bacterial taxon found across all developmental stages of field-collected Culex mosquitoes, but was rare in mosquitoes from laboratory-reared colonies. The proportion of Thorsellia sequences in the microbiomes of mosquito life stages varied ontogenetically with the greatest proportions recovered from the pupae of C. tarsalis and the lowest from newly emerged adults. The microbiome of field-collected late instar larvae was not influenced significantly by differences in the microbiota of the habitat due to habitat age or biopesticide treatments. The microbiome diversity was the greatest in the early instar larvae and the lowest in laboratory-reared mosquitoes.
  
  
  CONCLUSIONS
  Bacterial communities in early instar C. tarsalis larvae were significantly more diverse when compared to late instar larvae, pupae and newly emerged adults. Some of the bacterial OTUs found in the early instar larvae were also found across developmental stages. Thorsellia dominated the bacterial communities in field-collected immature stages but occurred at much lower relative abundance in adults. Differences in microbiota observed in larval habitats did not influence bacterial community profiles of late instar larvae or adults. However, bacterial communities in laboratory-reared C. tarsalis larvae differed significantly from the field. Determining the role of Thorsellia in mosquitoes and its distribution across different species of mosquitoes warrants further investigation.
authors.affiliation: Department of Entomology, University of California Riverside, Riverside, CA, 92521, USA. duguma@ufl.edu.|Present address: Florida Medical Entomology Laboratory, University of Florida, Vero Beach, FL, 32962, USA. duguma@ufl.edu.
authors.forename: Dagne
authors.initials: D
authors.lastname: Duguma
authors.affiliation: Department of Biology, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada. hallm2533@gmail.com.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Hall
authors.affiliation: Department of Entomology, University of California Riverside, Riverside, CA, 92521, USA. paul.rugman-jones@ucr.edu.
authors.forename: Paul
authors.initials: P
authors.lastname: Rugman-Jones
authors.affiliation: Department of Entomology, University of California Riverside, Riverside, CA, 92521, USA. richard.stouthamer@ucr.edu.
authors.forename: Richard
authors.initials: R
authors.lastname: Stouthamer
authors.affiliation: Department of Ecology, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden. Olle.Terenius@slu.se.
authors.forename: Olle
authors.initials: O
authors.lastname: Terenius
authors.affiliation: Department of Biology, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada. jneufeld@uwaterloo.ca.
authors.forename: Josh D
authors.initials: JD
authors.lastname: Neufeld
authors.affiliation: Department of Entomology, University of California Riverside, Riverside, CA, 92521, USA. william.walton@ucr.edu.
authors.forename: William E
authors.initials: WE
authors.lastname: Walton
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification / Q000235:genetics; D016000:Cluster Analysis; D003465:Culex / Q000254:growth & development* / Q000382:microbiology*; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D041981:Gastrointestinal Tract / Q000382:microbiology; D007814:Larva / Q000382:microbiology; D064307:Microbiota; D008969:Molecular Sequence Data; D010802:Phylogeny; D011679:Pupa / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S