The reduced genome of a heritable symbiont from an ectoparasitic feather feeding louse
Open Access
- 2 June 2021
- journal article
- research article
- Published by Springer Science and Business Media LLC in BMC Ecology and Evolution
- Vol. 21 (1), 1-11
- https://doi.org/10.1186/s12862-021-01840-7
Abstract
Background: Feather feeding lice are abundant and diverse ectoparasites that complete their entire life cycle on an avian host. The principal or sole source of nutrition for these lice is feathers. Feathers appear to lack four amino acids that the lice would require to complete development and reproduce. Several insect groups have acquired heritable and intracellular bacteria that can synthesize metabolites absent in an insect’s diet, allowing insects to feed exclusively on nutrient-poor resources. Multiple species of feather feeding lice have been shown to harbor heritable and intracellular bacteria. We expected that these bacteria augment the louse’s diet with amino acids and facilitated the evolution of these diverse and specialized parasites. Heritable symbionts of insects often have small genomes that contain a minimal set of genes needed to maintain essential cell functions and synthesize metabolites absent in the host insect’s diet. Therefore, we expected the genome of a bacterial endosymbiont in feather lice would be small, but encode pathways for biosynthesis of amino acids. Results: We sequenced the genome of a bacterial symbiont from a feather feeding louse (Columbicola wolffhuegeli) that parasitizes the Pied Imperial Pigeon (Ducula bicolor) and used its genome to predict metabolism of amino acids based on the presence or absence of genes. We found that this bacterial symbiont has a small genome, similar to the genomes of heritable symbionts described in other insect groups. However, we failed to identify many of the genes that we expected would support metabolism of amino acids in the symbiont genome. We also evaluated other gene pathways and features of the highly reduced genome of this symbiotic bacterium. Conclusions: Based on the data collected in this study, it does not appear that this bacterial symbiont can synthesize amino acids needed to complement the diet of a feather feeding louse. Our results raise additional questions about the biology of feather chewing lice and the roles of symbiotic bacteria in evolution of diverse avian parasites.Keywords
Funding Information
- Virginia Commonwealth University Life Sciences and National Science Foundation awards (DEB-1239788, DEB-1342604, DEB-1855812, DEB-1926919)
This publication has 56 references indexed in Scilit:
- Phylogenetic analysis of symbionts in feather-feeding lice of the genus Columbicola: evidence for repeated symbiont replacementsBMC Evolutionary Biology, 2013
- Arthropods and inherited bacteria: from counting the symbionts to understanding how symbionts countBMC Biology, 2013
- Fast gapped-read alignment with Bowtie 2Nature Methods, 2012
- Genome sequences of the human body louse and its primary endosymbiont provide insights into the permanent parasitic lifestyleProceedings of the National Academy of Sciences of the United States of America, 2010
- Genomic organization and molecular phylogenies of the beta (β) keratin multigene family in the chicken (Gallus gallus) and zebra finch (Taeniopygia guttata): implications for feather evolutionBMC Evolutionary Biology, 2010
- Origin of an Alternative Genetic Code in the Extremely Small and GC–Rich Genome of a Bacterial SymbiontPLoS Genetics, 2009
- Hamiltonella defensa , genome evolution of protective bacterial endosymbiont from pathogenic ancestorsProceedings of the National Academy of Sciences of the United States of America, 2009
- The RAST Server: Rapid Annotations using Subsystems TechnologyBMC Genomics, 2008
- Bacterial Endosymbiont of the Slender Pigeon Louse, Columbicola columbae , Allied to Endosymbionts of Grain Weevils and Tsetse FliesApplied and Environmental Microbiology, 2007
- MUSCLE: multiple sequence alignment with high accuracy and high throughputNucleic Acids Research, 2004