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Michel Solignac - One of the best experts on this subject based on the ideXlab platform.
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control of reproductive dominance by the Thelytoky gene in honeybees
Biology Letters, 2007Co-Authors: Michael H G Lattorff, Robin F. A. Moritz, Robin M Crewe, Michel SolignacAbstract:Differentiation into castes and reproductive division of labour are a characteristics of eusocial insects. Caste determination occurs at an early stage of larval development in social bees and is achieved via differential nutrition irrespective of the genotype. Workers are usually subordinate to the queen and altruistically refrain from reproduction. Workers of the Cape honeybee ( Apis mellifera capensis ) do not necessarily refrain from reproduction. They have the unique ability to produce female offspring parthenogenetically (Thelytoky) and can develop into ‘pseudoqueens’. Although these are morphologically workers, they develop a queen-like phenotype with respect to physiology and behaviour. Thelytoky is determined by a single gene ( th ) and we show that this gene also influences other traits related to the queen phenotype, including egg production and queen pheromone synthesis. Using 566 microsatellite markers, we mapped this gene to chromosome 13 and identified a candidate locus Thelytoky , similar to grainy head (a transcription factor), which has been shown to be highly expressed in queens of eusocial insects. We therefore suggest that this gene is not only important for determining the pseudoqueen phenotype in A. m. capensis workers, but is also of general importance in regulating the gene cascades controlling reproduction and sterility in female social bees.
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distribution and phylogeny of wolbachia inducing Thelytoky in rhoditini and aylacini hymenoptera cynipidae
Insect Molecular Biology, 1999Co-Authors: O Plantard, Jeanyves Rasplus, G Mondor, Le I Clainche, Michel SolignacAbstract:: Wolbachia are endosymbiotic bacteria responsible for Thelytoky in several parasitoid hymenopteran genera. After finding these micro-organisms in some populations of Diplolepis spinosissimae (Hymenoptera: Cynipidae) where they are responsible for Thelytoky through gamete duplication, we searched for Wolbachia spp. using specific PCR primers in nineteen other species of the Rhoditini tribe (rose gallwasps) and eight species of the 'Aylacini' tribe (gallwasps associated with herbaceous plants). Wolbachia were found in twelve Rhoditini species and four 'Aylacini' species. The most infected species have very few males (spanandry) and the Thelytoky of infected species/arrhenotoky of uninfected species is confirmed by previous research based on the sex of the offspring of virgin females. Phylogenetic analyses based on the partial Wolbachia ftsZ gene sequences indicate that some strains associated with closely related gallwasps are phylogenetically distant, suggesting that cynipids have been affected by several infection events. In contrast, the five infected European species of Diplolepis harbour the same strain of Wolbachia.
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wolbachia induced Thelytoky in the rose gallwasp diplolepis spinosissimae giraud hymenoptera cynipidae and its consequences on the genetic structure of its host
Proceedings of The Royal Society B: Biological Sciences, 1998Co-Authors: O Plantard, Jeanyves Rasplus, G Mondor, Le I Clainche, Michel SolignacAbstract:Cynipids are known to use various reproductive modes (arrhenotoky, Thelytoky and strict cyclical parthenogenesis), but the mechanism remains unknown. We have studied the reproductive system of a rose gallwasp, Diplolepis spinosissimae, which was found to exhibit two different reproductive systems according to the population. In eight out of the ten populations studied, all along the Atlantic coast, D. spinosissimae is thelytokous. Males are extremely rare, and all females are homozygous at three microsatellite loci. 'Obligate homozygous parthenogenesis' was found to be strictly associated with the presence of the endosymbiotic bacterium Wolbachia sp. In the two remaining populations, deprived of Wolbachia, D. spinosissimae reproduced by arrhenotoky as indicated by the larger frequency of males and heterozygosity of females. Allelic diversity, although not zero, was highly reduced in the coastal populations, as a consequence of Thelytoky and gamete duplication. We hypothesize that mating of uninfected males with infected females during the first generations after an infection event could explain the small but significant amount of polymorphism observed in those populations. The high level of differentiation indicates a low gene flow, even between geographically close coastal populations.
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Wolbachia–induced Thelytoky in the rose gallwasp Diplolepis spinosissimae (Giraud) (Hymenoptera: Cynipidae), and its consequences on the genetic structure of its host
Proceedings of The Royal Society B: Biological Sciences, 1998Co-Authors: O Plantard, Jeanyves Rasplus, G Mondor, I. Le Clainche, Michel SolignacAbstract:Cynipids are known to use various reproductive modes (arrhenotoky, Thelytoky and strict cyclical parthenogenesis), but the mechanism remains unknown. We have studied the reproductive system of a rose gallwasp, Diplolepis spinosissimae, which was found to exhibit two different reproductive systems according to the population. In eight out of the ten populations studied, all along the Atlantic coast, D. spinosissimae is thelytokous. Males are extremely rare, and all females are homozygous at three microsatellite loci. 'Obligate homozygous parthenogenesis' was found to be strictly associated with the presence of the endosymbiotic bacterium Wolbachia sp. In the two remaining populations, deprived of Wolbachia, D. spinosissimae reproduced by arrhenotoky as indicated by the larger frequency of males and heterozygosity of females. Allelic diversity, although not zero, was highly reduced in the coastal populations, as a consequence of Thelytoky and gamete duplication. We hypothesize that mating of uninfected males with infected females during the first generations after an infection event could explain the small but significant amount of polymorphism observed in those populations. The high level of differentiation indicates a low gene flow, even between geographically close coastal populations.
O Plantard - One of the best experts on this subject based on the ideXlab platform.
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distribution and phylogeny of wolbachia inducing Thelytoky in rhoditini and aylacini hymenoptera cynipidae
Insect Molecular Biology, 1999Co-Authors: O Plantard, Jeanyves Rasplus, G Mondor, Le I Clainche, Michel SolignacAbstract:: Wolbachia are endosymbiotic bacteria responsible for Thelytoky in several parasitoid hymenopteran genera. After finding these micro-organisms in some populations of Diplolepis spinosissimae (Hymenoptera: Cynipidae) where they are responsible for Thelytoky through gamete duplication, we searched for Wolbachia spp. using specific PCR primers in nineteen other species of the Rhoditini tribe (rose gallwasps) and eight species of the 'Aylacini' tribe (gallwasps associated with herbaceous plants). Wolbachia were found in twelve Rhoditini species and four 'Aylacini' species. The most infected species have very few males (spanandry) and the Thelytoky of infected species/arrhenotoky of uninfected species is confirmed by previous research based on the sex of the offspring of virgin females. Phylogenetic analyses based on the partial Wolbachia ftsZ gene sequences indicate that some strains associated with closely related gallwasps are phylogenetically distant, suggesting that cynipids have been affected by several infection events. In contrast, the five infected European species of Diplolepis harbour the same strain of Wolbachia.
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wolbachia induced Thelytoky in the rose gallwasp diplolepis spinosissimae giraud hymenoptera cynipidae and its consequences on the genetic structure of its host
Proceedings of The Royal Society B: Biological Sciences, 1998Co-Authors: O Plantard, Jeanyves Rasplus, G Mondor, Le I Clainche, Michel SolignacAbstract:Cynipids are known to use various reproductive modes (arrhenotoky, Thelytoky and strict cyclical parthenogenesis), but the mechanism remains unknown. We have studied the reproductive system of a rose gallwasp, Diplolepis spinosissimae, which was found to exhibit two different reproductive systems according to the population. In eight out of the ten populations studied, all along the Atlantic coast, D. spinosissimae is thelytokous. Males are extremely rare, and all females are homozygous at three microsatellite loci. 'Obligate homozygous parthenogenesis' was found to be strictly associated with the presence of the endosymbiotic bacterium Wolbachia sp. In the two remaining populations, deprived of Wolbachia, D. spinosissimae reproduced by arrhenotoky as indicated by the larger frequency of males and heterozygosity of females. Allelic diversity, although not zero, was highly reduced in the coastal populations, as a consequence of Thelytoky and gamete duplication. We hypothesize that mating of uninfected males with infected females during the first generations after an infection event could explain the small but significant amount of polymorphism observed in those populations. The high level of differentiation indicates a low gene flow, even between geographically close coastal populations.
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Wolbachia–induced Thelytoky in the rose gallwasp Diplolepis spinosissimae (Giraud) (Hymenoptera: Cynipidae), and its consequences on the genetic structure of its host
Proceedings of The Royal Society B: Biological Sciences, 1998Co-Authors: O Plantard, Jeanyves Rasplus, G Mondor, I. Le Clainche, Michel SolignacAbstract:Cynipids are known to use various reproductive modes (arrhenotoky, Thelytoky and strict cyclical parthenogenesis), but the mechanism remains unknown. We have studied the reproductive system of a rose gallwasp, Diplolepis spinosissimae, which was found to exhibit two different reproductive systems according to the population. In eight out of the ten populations studied, all along the Atlantic coast, D. spinosissimae is thelytokous. Males are extremely rare, and all females are homozygous at three microsatellite loci. 'Obligate homozygous parthenogenesis' was found to be strictly associated with the presence of the endosymbiotic bacterium Wolbachia sp. In the two remaining populations, deprived of Wolbachia, D. spinosissimae reproduced by arrhenotoky as indicated by the larger frequency of males and heterozygosity of females. Allelic diversity, although not zero, was highly reduced in the coastal populations, as a consequence of Thelytoky and gamete duplication. We hypothesize that mating of uninfected males with infected females during the first generations after an infection event could explain the small but significant amount of polymorphism observed in those populations. The high level of differentiation indicates a low gene flow, even between geographically close coastal populations.
Leo W Beukeboom - One of the best experts on this subject based on the ideXlab platform.
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diploid males support a two step mechanism of endosymbiont induced Thelytoky in a parasitoid wasp
BMC Evolutionary Biology, 2015Co-Authors: Bart A Pannebakker, Louis Van De Zande, Tanja Schwander, Bregje Wertheim, Leo W BeukeboomAbstract:Background Haplodiploidy, where females develop from diploid, fertilized eggs and males from haploid, unfertilized eggs, is abundant in some insect lineages. Some species in these lineages reproduce by Thelytoky that is caused by infection with endosymbionts: infected females lay haploid eggs that undergo diploidization and develop into females, while males are very rare or absent. It is generally assumed that in thelytokous wasps, endosymbionts merely diploidize the unfertilized eggs, which would then trigger female development.
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Transcriptome and proteome analysis of ovaries of arrhenotokous and thelytokous Venturia canescens.
Insect Molecular Biology, 2009Co-Authors: I. Mateo Leach, Leo W Beukeboom, A. Hesseling, W.h.c. Huibers, H. Witsenboer, L. Van De ZandeAbstract:Under arrhenotoky, unfertilized haploid eggs develop as males but under Thelytoky they develop into diploid females after they have undergone diploidy restoration. In the parasitoid wasp Venturia canescens both reproductive modes occur. Thelytoky is genetically determined but the underlying genetics of diploidy restoration remain unknown. In this study we aim to identify the genes and/or proteins that control Thelytoky. cDNA-amplified fragment length polymorphism (cDNA-AFLP) analysis of total ovarian RNA and two-dimensional protein electrophoresis in combination with mass spectrometry revealed putative transcripts and proteins involved in arrhenotokous and thelytokous development. The detected tubulin and actin protein differences are most likely functionally related to the two types of reproduction.
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Thelytoky in hymenoptera with venturia canescens and leptopilina clavipes as case studies
Lost Sex. The Evolutionary Biology of Parthenogenesis, 2009Co-Authors: Irene Mateo Leach, Bart A Pannebakker, Maria Victoria Schneider, Gerard Driessen, Louis Van De Zande, Leo W BeukeboomAbstract:The insect order of Hymenoptera comprises around 200.000 described species of ants, bees, wasps and sawflies, many of which serve important ecological and economic functions. All Hymenoptera have a haplodiploid mode of reproduction. Males always develop from unfertilized eggs and are haploid. Females are always diploid and can develop from both fertilized and unfertilized eggs. Within haplodiploidy, arrhenotoky is the most common mode of reproduction: unfertilized eggs develop into males that are haploid and 100% related to their mother, whereas fertilized eggs yield diploid females with a haploid complement of both parents. Thelytoky is a less common mode of reproduction. Thelytokous females develop parthenogenetically from unfertilized eggs after restoration of diploidy and are 100% related to their mother. Two distinctive classes of Thelytoky can be distinguished based upon the causal mechanism: Thelytoky can be induced by nuclear genes or be based on cytoplasmic genes including microorganisms. Most thelytokous hymenopterans reproduce by some form of automixis: both terminal fusion and central fusion have been found, while most cases of microbe-induced Thelytoky are a form of gamete duplication. These different mechanisms can have a number of important implications for the genetic make-up of individuals and the amount and structure of genetic variation in populations. We discuss these implications and their evolutionary consequences, with a special focus on the ichneumonid parasitoid wasp Venturia canescens, in which Thelytoky has a genetic basis, and the figitid parasitoid wasp Leptopilina clavipes, which has Wolbachia-induced Thelytoky.
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Automictic parthenogenesis in the parasitoid Venturia canescens (Hymenoptera: Ichneumonidae) revisited.
Genome, 2000Co-Authors: Leo W Beukeboom, L. P. PijnackerAbstract:Both arrhenotokous and thelytokous reproduction are known to occur in the parasitoid wasp Venturia canescens. The cytological mechanism of Thelytoky was previously reported to involve the formation of a restitution metaphase after the reduction division, but the exact nature of the subsequent divisions, whether reductional or equational, remained unclear. We reinvestigated the cytological mechanisms in a thelytokous strain collected in France. Our observations confirm previous results, but an equational and not a reduction division was observed after restitution. This type of reproduction can be classified as central fusion automictic parthenogenesis. In two arrhenotokous strains the normal pattern of oogenesis and syngamy of Hymenoptera was observed. In addition, we used PCR amplification to show that Thelytoky in V. canescens is not caused by Wolbachia bacteria. The results are discussed in relation to maintenance of heterozygosity and female sex.
Jeanyves Rasplus - One of the best experts on this subject based on the ideXlab platform.
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distribution and phylogeny of wolbachia inducing Thelytoky in rhoditini and aylacini hymenoptera cynipidae
Insect Molecular Biology, 1999Co-Authors: O Plantard, Jeanyves Rasplus, G Mondor, Le I Clainche, Michel SolignacAbstract:: Wolbachia are endosymbiotic bacteria responsible for Thelytoky in several parasitoid hymenopteran genera. After finding these micro-organisms in some populations of Diplolepis spinosissimae (Hymenoptera: Cynipidae) where they are responsible for Thelytoky through gamete duplication, we searched for Wolbachia spp. using specific PCR primers in nineteen other species of the Rhoditini tribe (rose gallwasps) and eight species of the 'Aylacini' tribe (gallwasps associated with herbaceous plants). Wolbachia were found in twelve Rhoditini species and four 'Aylacini' species. The most infected species have very few males (spanandry) and the Thelytoky of infected species/arrhenotoky of uninfected species is confirmed by previous research based on the sex of the offspring of virgin females. Phylogenetic analyses based on the partial Wolbachia ftsZ gene sequences indicate that some strains associated with closely related gallwasps are phylogenetically distant, suggesting that cynipids have been affected by several infection events. In contrast, the five infected European species of Diplolepis harbour the same strain of Wolbachia.
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wolbachia induced Thelytoky in the rose gallwasp diplolepis spinosissimae giraud hymenoptera cynipidae and its consequences on the genetic structure of its host
Proceedings of The Royal Society B: Biological Sciences, 1998Co-Authors: O Plantard, Jeanyves Rasplus, G Mondor, Le I Clainche, Michel SolignacAbstract:Cynipids are known to use various reproductive modes (arrhenotoky, Thelytoky and strict cyclical parthenogenesis), but the mechanism remains unknown. We have studied the reproductive system of a rose gallwasp, Diplolepis spinosissimae, which was found to exhibit two different reproductive systems according to the population. In eight out of the ten populations studied, all along the Atlantic coast, D. spinosissimae is thelytokous. Males are extremely rare, and all females are homozygous at three microsatellite loci. 'Obligate homozygous parthenogenesis' was found to be strictly associated with the presence of the endosymbiotic bacterium Wolbachia sp. In the two remaining populations, deprived of Wolbachia, D. spinosissimae reproduced by arrhenotoky as indicated by the larger frequency of males and heterozygosity of females. Allelic diversity, although not zero, was highly reduced in the coastal populations, as a consequence of Thelytoky and gamete duplication. We hypothesize that mating of uninfected males with infected females during the first generations after an infection event could explain the small but significant amount of polymorphism observed in those populations. The high level of differentiation indicates a low gene flow, even between geographically close coastal populations.
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Wolbachia–induced Thelytoky in the rose gallwasp Diplolepis spinosissimae (Giraud) (Hymenoptera: Cynipidae), and its consequences on the genetic structure of its host
Proceedings of The Royal Society B: Biological Sciences, 1998Co-Authors: O Plantard, Jeanyves Rasplus, G Mondor, I. Le Clainche, Michel SolignacAbstract:Cynipids are known to use various reproductive modes (arrhenotoky, Thelytoky and strict cyclical parthenogenesis), but the mechanism remains unknown. We have studied the reproductive system of a rose gallwasp, Diplolepis spinosissimae, which was found to exhibit two different reproductive systems according to the population. In eight out of the ten populations studied, all along the Atlantic coast, D. spinosissimae is thelytokous. Males are extremely rare, and all females are homozygous at three microsatellite loci. 'Obligate homozygous parthenogenesis' was found to be strictly associated with the presence of the endosymbiotic bacterium Wolbachia sp. In the two remaining populations, deprived of Wolbachia, D. spinosissimae reproduced by arrhenotoky as indicated by the larger frequency of males and heterozygosity of females. Allelic diversity, although not zero, was highly reduced in the coastal populations, as a consequence of Thelytoky and gamete duplication. We hypothesize that mating of uninfected males with infected females during the first generations after an infection event could explain the small but significant amount of polymorphism observed in those populations. The high level of differentiation indicates a low gene flow, even between geographically close coastal populations.
G Mondor - One of the best experts on this subject based on the ideXlab platform.
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distribution and phylogeny of wolbachia inducing Thelytoky in rhoditini and aylacini hymenoptera cynipidae
Insect Molecular Biology, 1999Co-Authors: O Plantard, Jeanyves Rasplus, G Mondor, Le I Clainche, Michel SolignacAbstract:: Wolbachia are endosymbiotic bacteria responsible for Thelytoky in several parasitoid hymenopteran genera. After finding these micro-organisms in some populations of Diplolepis spinosissimae (Hymenoptera: Cynipidae) where they are responsible for Thelytoky through gamete duplication, we searched for Wolbachia spp. using specific PCR primers in nineteen other species of the Rhoditini tribe (rose gallwasps) and eight species of the 'Aylacini' tribe (gallwasps associated with herbaceous plants). Wolbachia were found in twelve Rhoditini species and four 'Aylacini' species. The most infected species have very few males (spanandry) and the Thelytoky of infected species/arrhenotoky of uninfected species is confirmed by previous research based on the sex of the offspring of virgin females. Phylogenetic analyses based on the partial Wolbachia ftsZ gene sequences indicate that some strains associated with closely related gallwasps are phylogenetically distant, suggesting that cynipids have been affected by several infection events. In contrast, the five infected European species of Diplolepis harbour the same strain of Wolbachia.
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wolbachia induced Thelytoky in the rose gallwasp diplolepis spinosissimae giraud hymenoptera cynipidae and its consequences on the genetic structure of its host
Proceedings of The Royal Society B: Biological Sciences, 1998Co-Authors: O Plantard, Jeanyves Rasplus, G Mondor, Le I Clainche, Michel SolignacAbstract:Cynipids are known to use various reproductive modes (arrhenotoky, Thelytoky and strict cyclical parthenogenesis), but the mechanism remains unknown. We have studied the reproductive system of a rose gallwasp, Diplolepis spinosissimae, which was found to exhibit two different reproductive systems according to the population. In eight out of the ten populations studied, all along the Atlantic coast, D. spinosissimae is thelytokous. Males are extremely rare, and all females are homozygous at three microsatellite loci. 'Obligate homozygous parthenogenesis' was found to be strictly associated with the presence of the endosymbiotic bacterium Wolbachia sp. In the two remaining populations, deprived of Wolbachia, D. spinosissimae reproduced by arrhenotoky as indicated by the larger frequency of males and heterozygosity of females. Allelic diversity, although not zero, was highly reduced in the coastal populations, as a consequence of Thelytoky and gamete duplication. We hypothesize that mating of uninfected males with infected females during the first generations after an infection event could explain the small but significant amount of polymorphism observed in those populations. The high level of differentiation indicates a low gene flow, even between geographically close coastal populations.
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Wolbachia–induced Thelytoky in the rose gallwasp Diplolepis spinosissimae (Giraud) (Hymenoptera: Cynipidae), and its consequences on the genetic structure of its host
Proceedings of The Royal Society B: Biological Sciences, 1998Co-Authors: O Plantard, Jeanyves Rasplus, G Mondor, I. Le Clainche, Michel SolignacAbstract:Cynipids are known to use various reproductive modes (arrhenotoky, Thelytoky and strict cyclical parthenogenesis), but the mechanism remains unknown. We have studied the reproductive system of a rose gallwasp, Diplolepis spinosissimae, which was found to exhibit two different reproductive systems according to the population. In eight out of the ten populations studied, all along the Atlantic coast, D. spinosissimae is thelytokous. Males are extremely rare, and all females are homozygous at three microsatellite loci. 'Obligate homozygous parthenogenesis' was found to be strictly associated with the presence of the endosymbiotic bacterium Wolbachia sp. In the two remaining populations, deprived of Wolbachia, D. spinosissimae reproduced by arrhenotoky as indicated by the larger frequency of males and heterozygosity of females. Allelic diversity, although not zero, was highly reduced in the coastal populations, as a consequence of Thelytoky and gamete duplication. We hypothesize that mating of uninfected males with infected females during the first generations after an infection event could explain the small but significant amount of polymorphism observed in those populations. The high level of differentiation indicates a low gene flow, even between geographically close coastal populations.
