Buchnera has changed flatmate but the repeated replacement of co-obligate symbionts is not associated with the ecological expansions of their aphid hosts

AbstractSymbiotic associations with bacteria have facilitated important evolutionary transitions in insects and resulted in long-term obligate interactions. Recent evidence suggests that these associations are not always evolutionarily stable and that symbiont replacement and/or supplementation of an obligate symbiosis by an additional bacterium has occurred during the history of many insect groups. Yet, the factors favoring one symbiont over another in this evolutionary dynamic are not well understood; progress has been hindered by our incomplete understanding of the distribution of symbionts across phylogenetic and ecological contexts. While many aphids are engaged into an obligate symbiosis with a single Gammaproteobacterium, Buchnera aphidicola, in species of the Lachninae subfamily, this relationship has evolved into a “ménage à trois”, in which Buchnera is complemented by a cosymbiont, usually Serratia symbiotica. Using deep sequencing of 16S rRNA bacterial genes from 128 species of Cinara (the most diverse Lachninae genus), we reveal a highly dynamic dual symbiotic system in this aphid lineage. Most species host both Serratia and Buchnera but, in several clades, endosymbionts related to Sodalis, Erwinia or an unnamed member of the Enterobacteriaceae have replaced Serratia. Endosymbiont genome sequences from four aphid species+confirm that these coresident symbionts fulfill essential metabolic functions not ensured by Buchnera. We further demonstrate through comparative phylogenetic analyses that co-symbiont replacement is not associated with the adaptation of aphids to new ecological conditions. We propose that symbiont succession was driven by factors intrinsic to the phenomenon of endosymbiosis, such as rapid genome deterioration or competitive interactions between bacteria with similar metabolic capabilities.

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New Insights on the Evolutionary History of Aphids and Their Primary Endosymbiont Buchnera aphidicola

International Journal of Evolutionary Biology ◽

10.4061/2011/250154 ◽

2011 ◽

Vol 2011 ◽

pp. 1-9 ◽

Cited By ~ 8

Author(s):

Vicente Pérez-Brocal ◽

Rosario Gil ◽

Andrés Moya ◽

Amparo Latorre

Keyword(s):

Generation Time ◽

Evolutionary History ◽

Parallel Evolution ◽

Aphid Species ◽

Evolutionary Analysis ◽

Buchnera Aphidicola ◽

Genomic Features ◽

Evolutionary Pattern ◽

History Of ◽

Molecular Evolutionary Analysis

Since the establishment of the symbiosis between the ancestor of modern aphids and their primary endosymbiont, Buchnera aphidicola, insects and bacteria have coevolved. Due to this parallel evolution, the analysis of bacterial genomic features constitutes a useful tool to understand their evolutionary history. Here we report, based on data from B. aphidicola, the molecular evolutionary analysis, the phylogenetic relationships among lineages and a comparison of sequence evolutionary rates of symbionts of four aphid species from three subfamilies. Our results support previous hypotheses of divergence of B. aphidicola and their host lineages during the early Cretaceous and indicate a closer relationship between subfamilies Eriosomatinae and Lachninae than with the Aphidinae. They also reveal a general evolutionary pattern among strains at the functional level. We also point out the effect of lifecycle and generation time as a possible explanation for the accelerated rate in B. aphidicola from the Lachninae.

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Serial horizontal transfer of vitamin-biosynthetic genes enables the establishment of new nutritional symbionts in aphids’ di-symbiotic systems

The ISME Journal ◽

10.1038/s41396-019-0533-6 ◽

2019 ◽

Vol 14 (1) ◽

pp. 259-273 ◽

Cited By ~ 13

Author(s):

Alejandro Manzano-Marı́n ◽

Armelle Coeur d’acier ◽

Anne-Laure Clamens ◽

Céline Orvain ◽

Corinne Cruaud ◽

...

Keyword(s):

In Situ Hybridisation ◽

Essential Amino Acids ◽

Aphid Species ◽

Fluorescence In Situ Hybridisation ◽

The Novel ◽

Buchnera Aphidicola ◽

Biosynthetic Genes ◽

Obligate Symbiont

Abstract Many insects depend on obligate mutualistic bacteria to provide essential nutrients lacking from their diet. Most aphids, whose diet consists of phloem, rely on the bacterial endosymbiont Buchnera aphidicola to supply essential amino acids and B vitamins. However, in some aphid species, provision of these nutrients is partitioned between Buchnera and a younger bacterial partner, whose identity varies across aphid lineages. Little is known about the origin and the evolutionary stability of these di-symbiotic systems. It is also unclear whether the novel symbionts merely compensate for losses in Buchnera or carry new nutritional functions. Using whole-genome endosymbiont sequences of nine Cinara aphids that harbour an Erwinia-related symbiont to complement Buchnera, we show that the Erwinia association arose from a single event of symbiont lifestyle shift, from a free-living to an obligate intracellular one. This event resulted in drastic genome reduction, long-term genome stasis, and co-divergence with aphids. Fluorescence in situ hybridisation reveals that Erwinia inhabits its own bacteriocytes near Buchnera’s. Altogether these results depict a scenario for the establishment of Erwinia as an obligate symbiont that mirrors Buchnera’s. Additionally, we found that the Erwinia vitamin-biosynthetic genes not only compensate for Buchnera’s deficiencies, but also provide a new nutritional function; whose genes have been horizontally acquired from a Sodalis-related bacterium. A subset of these genes have been subsequently transferred to a new Hamiltonella co-obligate symbiont in one specific Cinara lineage. These results show that the establishment and dynamics of multi-partner endosymbioses can be mediated by lateral gene transfers between co-ocurring symbionts.

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100-My history of bornavirus infections hidden in vertebrate genomes

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2026235118 ◽

2021 ◽

Vol 118 (20) ◽

pp. e2026235118

Author(s):

Junna Kawasaki ◽

Shohei Kojima ◽

Yahiro Mukai ◽

Keizo Tomonaga ◽

Masayuki Horie

Keyword(s):

Phylogenetic Analyses ◽

Migration Route ◽

Messenger Rnas ◽

Molecular Fossil ◽

History Of ◽

Geographic Distributions ◽

Fossil Records ◽

Insight Into ◽

Animal Genomes

Although viruses have threatened our ancestors for millions of years, prehistoric epidemics of viruses are largely unknown. Endogenous bornavirus-like elements (EBLs) are ancient bornavirus sequences derived from the viral messenger RNAs that were reverse transcribed and inserted into animal genomes, most likely by retrotransposons. These elements can be used as molecular fossil records to trace past bornaviral infections. In this study, we systematically identified EBLs in vertebrate genomes and revealed the history of bornavirus infections over nearly 100 My. We confirmed that ancient bornaviral infections have occurred in diverse vertebrate lineages, especially in primate ancestors. Phylogenetic analyses indicated that primate ancestors were infected with various bornaviral lineages during evolution. EBLs in primate genomes formed clades according to their integration ages, suggesting that bornavirus lineages infected with primate ancestors had changed chronologically. However, some bornaviral lineages may have coexisted with primate ancestors and underwent repeated endogenizations for tens of millions of years. Moreover, a bornaviral lineage that coexisted with primate ancestors also endogenized in the genomes of some ancestral bats. The habitats of these bat ancestors have been reported to overlap with the migration route of primate ancestors. These results suggest that long-term virus–host coexistence expanded the geographic distributions of the bornaviral lineage along with primate migration and may have spread their infections to these bat ancestors. Our findings provide insight into the history of bornavirus infections over geological timescales that cannot be deduced from research using extant viruses alone, thus broadening our perspective on virus–host coevolution.

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New Clues about the Evolutionary History of Metabolic Losses in Bacterial Endosymbionts, Provided by the Genome of Buchnera aphidicola from the Aphid Cinara tujafilina

Applied and Environmental Microbiology ◽

10.1128/aem.00141-11 ◽

2011 ◽

Vol 77 (13) ◽

pp. 4446-4454 ◽

Cited By ~ 40

Author(s):

Araceli Lamelas ◽

María José Gosalbes ◽

Andrés Moya ◽

Amparo Latorre

Keyword(s):

Evolutionary History ◽

Acyrthosiphon Pisum ◽

Bacterial Genome ◽

Last Common Ancestor ◽

Symbiotic Association ◽

Gene Repertoire ◽

Buchnera Aphidicola ◽

Content Type ◽

History Of ◽

Serratia Symbiotica

ABSTRACTThe symbiotic association between aphids (Homoptera) andBuchnera aphidicola(Gammaproteobacteria) started about 100 to 200 million years ago. As a consequence of this relationship, the bacterial genome has undergone a prominent size reduction. The downsize genome process starts when the bacterium enters the host and will probably end with its extinction and replacement by another healthier bacterium or with the establishment of metabolic complementation between two or more bacteria. Nowadays, several complete genomes ofBuchnera aphidicolafrom four different aphid species (Acyrthosiphon pisum,Schizaphis graminum,Baizongia pistacea, andCinara cedri) have been fully sequenced.C. cedribelongs to the subfamily Lachninae and harbors two coprimary bacteria that fulfill the metabolic needs of the whole consortium:B. aphidicolawith the smallest genome reported so far and “CandidatusSerratia symbiotica.” In addition,Cinara tujafilina, another member of the subfamily Lachninae, closely related toC. cedri, also harbors “Ca.Serratia symbiotica” but with a different phylogenetic status than the one fromC. cedri. In this study, we present the complete genome sequence ofB. aphidicolafromC. tujafilinaand the phylogenetic analysis and comparative genomics with the otherBuchneragenomes. Furthermore, the gene repertoire of the last common ancestor has been inferred, and the evolutionary history of the metabolic losses that occurred in the different lineages has been analyzed. Although stochastic gene loss plays a role in the genome reduction process, it is also clear that metabolism, as a functional constraint, is also a powerful evolutionary force in insect endosymbionts.

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One hundred million years history of bornavirus infections hidden in vertebrate genomes

10.1101/2020.12.02.408005 ◽

2020 ◽

Author(s):

Junna Kawasaki ◽

Shohei Kojima ◽

Yahiro Mukai ◽

Keizo Tomonaga ◽

Masayuki Horie

Keyword(s):

Viral Infections ◽

Phylogenetic Analyses ◽

Migration Route ◽

Chronological Change ◽

History Of ◽

New Hosts ◽

Geographic Distributions ◽

Fossil Records ◽

Viral Lineage

AbstractAlthough viruses have threatened our ancestors for millions of years, prehistoric epidemics of viruses are largely unknown. Endogenous bornavirus-like elements (EBLs) are ancient viral sequences that have been integrated into animal genomes. These elements can be used as molecular fossil records to trace past bornaviral infections. In this study, we systematically identified EBLs in vertebrate genomes and revealed the history of bornavirus infections over nearly 100 million years. We found that ancient bornaviral infections have occurred in diverse vertebrate lineages, especially in primate ancestors. Phylogenetic analyses indicated that primate ancestors had been infected with various bornaviral lineages during evolution. Moreover, EBLs in primate genomes formed clades according to their integration ages, suggesting that epidemic lineages of bornaviruses had changed chronologically. However, we found that some bornaviral lineages coexisted with primate ancestors and underwent repeated endogenizations for tens of millions of years. Furthermore, this viral lineage that coexisted with primate ancestors was also endogenized in some ancestral bats. Notably, the geographic distributions of these bat ancestors have been reported to overlap with the migration route of primate ancestors, suggesting that long-term virus-host coexistence could have expanded the geographic distributions of the viral lineage and might have spread their infections to new hosts. Thus, our findings describe hidden virus-host co-evolutionary history over geological timescales, including chronological change in epidemic bornaviral lineages, long-term virus-host coexistence, and expansion of viral infections.

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Ubiquity of the Symbiont Serratia symbiotica in the Aphid Natural Environment: Distribution, Diversity and Evolution at a Multitrophic Level

10.1101/2021.04.18.440331 ◽

2021 ◽

Author(s):

Inès Pons ◽

Nora Scieur ◽

Linda Dhondt ◽

Marie-Eve Renard ◽

François Renoz ◽

...

Keyword(s):

Evolutionary Ecology ◽

Phylogenetic Analyses ◽

Aphid Species ◽

Trophic Levels ◽

Ecological Interactions ◽

Potential Reservoir ◽

Serratia Symbiotica ◽

Insect Symbionts ◽

Horizontal Transfers ◽

First Time

ABSTRACTBacterial symbioses are significant drivers of insect evolutionary ecology. However, despite recent findings that these associations can emerge from environmentally derived bacterial precursors, there is still little information on how these potential progenitors of insect symbionts circulates in the trophic systems. The aphid symbiont Serratia symbiotica represents a valuable model for deciphering evolutionary scenarios of bacterial acquisition by insects, as its diversity includes intracellular host-dependent strains as well as gut-associated strains that have retained some ability to live independently of their hosts and circulate in plant phloem sap. These strains represent a potential reservoir for the emergence of new and more intimate symbioses. Here, we conducted a field study to examine the distribution and diversity of S. symbiotica found in aphid populations, as well as in different compartments of their surrounding environment. A total of 250 aphid colonies, 203 associated insects, and 161 plant samples associated with aphid colonies were screened for S. symbiotica. Twenty percent of aphids were infected with S. symbiotica, and the symbiont includes a wide diversity of strains with varied tissue tropism corresponding to different lifestyle. We also showed that the prevalence of S. symbiotica is influenced by seasonal temperatures. For the first time, we found that S. symbiotica was present in non aphid species and in host plants, and that the prevalence of the bacterium in these samples was higher when associated aphid colonies were infected. Furthermore, phylogenetic analyses suggest the existence of horizontal transfers between the different trophic levels examined. These results provide a completely new picture of the ubiquity of an insect symbiont in nature. They suggest that ecological interactions promote the dissemination of strains that are still free-living and poorly specialized, and for which plants are a proabable reservoir for the acquisition of new bacterial partners in insects.

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Evolution of the Secondary Symbiont “Candidatus Serratia symbiotica” in Aphid Species of the Subfamily Lachninae

Applied and Environmental Microbiology ◽

10.1128/aem.00022-08 ◽

2008 ◽

Vol 74 (13) ◽

pp. 4236-4240 ◽

Cited By ~ 66

Author(s):

Araceli Lamelas ◽

Vicente Pérez-Brocal ◽

Laura Gómez-Valero ◽

María José Gosalbes ◽

Andrés Moya ◽

...

Keyword(s):

Aphid Species ◽

Buchnera Aphidicola ◽

Secondary Symbiont ◽

Serratia Symbiotica

ABSTRACT Buchnera aphidicola BCc, the primary endosymbiont of the aphid Cinara cedri (subfamily Lachninae), is losing its symbiotic capacity and might be replaced by the coresident “Candidatus Serratia symbiotica.” Phylogenetic and morphological analyses within the subfamily Lachninae indicate two different “Ca. Serratia symbiotica” lineages and support the longtime coevolution of both symbionts in C. cedri.

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Atypical Femoral Fracture in McCune-Albright Syndrome

Journal of Research in Orthopedic Science ◽

10.32598/jrosj.7.3.711.1 ◽

2020 ◽

Vol 7 (3) ◽

pp. 147-152

Author(s):

Salman Ghaffari ◽

◽

Mehran Razavipour ◽

Parastoo Mohammad Amini ◽

◽

...

Keyword(s):

Femoral Fracture ◽

Dynamic Compression ◽

Plate Fixation ◽

Medullary Canal ◽

Mccune Albright Syndrome ◽

Café Au Lait Spots ◽

History Of ◽

Albright Syndrome ◽

Mccune Albright

McCune-Albright Syndrome (MAS) is characterized by endocrinopathies, café-au-lait spots, and fibrous dysplasia. Bisphosphonates are the most prescribed treatment for reducing the pain but their long-term use has been associated with atypical fractures of cortical bones like femur in patients. We present a 23-year-old girl diagnosed with MAS. She had an atypical mid-shaft left femoral fracture that happened during simple walking. She also had a history of long-term use of alendronate. Because of the narrow medullary canal, we used 14 holes hybrid locking plate for the lateral aspect of the thigh to fix the fracture and 5 holes dynamic compression plate (instead of the intramedullary nail) in the anterior surface to double fix it, reducing the probability of device failure. With double plate fixation and discontinuation of alendronate, the complete union was achieved five months after surgery

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European Integration

10.3366/edinburgh/9781474455893.001.0001 ◽

2020 ◽

Author(s):

Johann P. Arnason

Keyword(s):

European Integration ◽

Eastern European ◽

The European Union ◽

Historical Processes ◽

History Of ◽

External Conditions ◽

Eastern European Countries ◽

Totalitarian Regimes ◽

The Eu

Different understandings of European integration, its background and present problems are represented in this book, but they share an emphasis on historical processes, geopolitical dynamics and regional diversity. The introduction surveys approaches to the question of European continuities and discontinuities, before going on to an overview of chapters. The following three contributions deal with long-term perspectives, including the question of Europe as a civilisational entity, the civilisational crisis of the twentieth century, marked by wars and totalitarian regimes, and a comparison of the European Union with the Habsburg Empire, with particular emphasis on similar crisis symptoms. The next three chapters discuss various aspects and contexts of the present crisis. Reflections on the Brexit controversy throw light on a longer history of intra-Union rivalry, enduring disputes and changing external conditions. An analysis of efforts to strengthen the EU’s legal and constitutional framework, and of resistances to them, highlights the unfinished agenda of integration. A closer look at the much-disputed Islamic presence in Europe suggests that an interdependent radicalization of Islamism and the European extreme right is a major factor in current political developments. Three concluding chapters adopt specific regional perspectives. Central and Eastern European countries, especially Poland, are following a path that leads to conflicts with dominant orientations of the EU, but this also raises questions about Europe’s future. The record of Scandinavian policies in relation to Europe exemplifies more general problems faced by peripheral regions. Finally, growing dissonances and divergences within the EU may strengthen the case for Eurasian perspectives.

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