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Name, Khesller Patrícia Olázia - One of the best experts on this subject based on the ideXlab platform.
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Morfologia comparada do aparelho reprodutor interno masculino e dos espermatozóides em espécies neotropicais de calliphoridae (diptera)
2012Co-Authors: Name, Khesller Patrícia OláziaAbstract:Dados morfológicos obtidos da análise do aparelho reprodutor interno e dos espermatozóides em invertebrados têm sido cada vez mais utilizados no sentido de fornecer soluções consistentes para uma melhor compreensão da história evolutivados grupos, uma vez que os dados morfológicos tradicionalmente utilizados não têm sido suficientes, no sentido de permitir tal compreensão. A família Calliphoridae é um exemplo do que foi dito anteriormente. Embora o conhecimento sobre essa família seja crucial para que se possa chegar ao entendimento da evolução dentro do grupo Oestroidea, até o presente momento, pouco se conhece sobre a morfologia interna de seus órgãos reprodutores e de seus espermatozóides. A presente tese avaliou a morfologia dos espermatozóides em doze espécies de califorídeos, sendo que oito destas espécies ocorrem no Brasil e três são espécies dos Andes Colombianos.Estruturalmente, o aparelho reprodutor interno masculino em Calliphoridae éformado por um par de testículos, ductos deferentes e glândulas acessórias, uma vesícula seminal e um ducto ejaculatório. A morfologia dos espermatozóides revelou a presença de polimorfismo relacionado ao comprimento dos espermatozóides. Os eventos da espermiogênese nas espécies analisadas são similares e seguem o padrão descrito para outros grupos de insetos, sendo a diferenciação caracterizada pela formação do acrossoma e do ‘Nebenkern’, condensação do núcleo,alongamento celular incluindo desenvolvimento do flagelo e perda de citoplasma. A análise ultra estrutural revelou que o espermatozóide é formado por duas regiões -xiida cabeça e do flagelo, sendo a zona intermediária entre essas duas, denominada zona de justaposição “overlap”. As organelas presentes na região da cabeça são aocrossoma e o núcleo, e na região do flagelo o axonema (9+9+2), os derivados mitocondriais e o adjunto do centríolo. Foi observado a presença de polimorfismo relacionado à morfologia nas organelas que formam o espermatozóide. Algumas espécies possuem dois derivados mitocondriais e outras apenas um derivado. Oacrossoma nas três espécies do gênero Lucilia e nas duas espécies de Hemilucilia analisadas é cônico e volumoso, enquanto nas demais espécies é cônico e delgado.A marcação com ácido etanólico fosfotúngstico - EPTA mostrou-se diferente nas diferentes espécies analisadas. Foi avaliado ainda, o perfil de marcação de resíduos de carboidratos nas espermátides e nos espermatozóides das espécies presentes no Brasil, uma vez que tais moléculas são responsáveis, pelo reconhecimento e interação entre os gametas. O mapeamento dos carboidratos de superfície nos espermatozóides nos forneceu dados cito químicos importantes que, aliados aos dados morfológicos já existentes, poderão ser úteis em estudos taxonômicos. _______________________________________________________________________________ ABSTRACTMorphological data obtained from the analysis of the internal reproductive tractand from sperm in invertebrates have been increasingly used to provide consistent solutions to understand more fully the evolutionary history of the groups, because the traditionally used morphological data have not been enough. The Calliphoridae familyis an example of this lack. Although knowledge about this family is crucial tounder standing evolution within the Oestroidea group, until now little is known aboutthe internal morphology of its reproductive organs and its sperm. The current thesisevaluated the sperm morphology in 12 species of Calliphoridae, nine of which occurin Brazil and three in the Colombian Andes. Structurally, the male internalreproductive apparatus in Calliphoridae is formed by a pair of testicles, deferentducts and accessory glands, a seminal vesicle and an ejaculatory duct. Spermmorphology revealed the presence of polymorphism related to their length. In thespecies studied, the spermatogenesis events are similar and follow the patterndescribed for other groups of insects, with differentiation being characterized by theformation of the acrosome and the “Nebenkern”, condensation of the nucleus, cellularlengthening including flagellum development, and loss of cytoplasm. Ultrastructuralanalysis revealed that the sperm is made up of two regions – the head and theflagellum, with the intermediate zone between the two being denominated theoverlap. The organelles present in the head region are the acrosome and thenucleus, and in the flagellum there is the axoneme (9+9+2), the mitochondrialderivatives and the centriolar adjunct. The presence of polymorphism was observed,xivrelated to the morphology of the organelles that form the sperm. Some speciespossess two mitochondrial derivatives and others only one. The acrosome in thethree species from the genus Lucilia and in the two species of Hemilucilia analyzed isconical and bulky, while in the other species it is conical and slender. Marking withethanolic phosphotungstic acid (EPTA) was seen to be different for the variousspecies analyzed. The profile of carbohydrate residue marking in the spermatids andsperm was also evaluated for the species present in Brazil, because these moleculesare responsible,for recognition and interaction among gametes. Mapping the surfacecarbohydrates in the sperm provided us with important cyto-chemical data which,together with the morphological data that already exist, may be useful in taxonomicstudies
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Morfologia comparada do aparelho reprodutor interno masculino e dos espermatozóides em espécies neotropicais de calliphoridae (diptera)
2012Co-Authors: Name, Khesller Patrícia OláziaAbstract:Tese (doutorada)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Biologia AnimalDados morfológicos obtidos da análise do aparelho reprodutor interno e dos espermatozóides em invertebrados têm sido cada vez mais utilizados no sentido de fornecer soluções consistentes para uma melhor compreensão da história evolutivados grupos, uma vez que os dados morfológicos tradicionalmente utilizados não têm sido suficientes, no sentido de permitir tal compreensão. A família Calliphoridae é um exemplo do que foi dito anteriormente. Embora o conhecimento sobre essa família seja crucial para que se possa chegar ao entendimento da evolução dentro do grupo Oestroidea, até o presente momento, pouco se conhece sobre a morfologia interna de seus órgãos reprodutores e de seus espermatozóides. A presente tese avaliou a morfologia dos espermatozóides em doze espécies de califorídeos, sendo que oito destas espécies ocorrem no Brasil e três são espécies dos Andes Colombianos.Estruturalmente, o aparelho reprodutor interno masculino em Calliphoridae éformado por um par de testículos, ductos deferentes e glândulas acessórias, uma vesícula seminal e um ducto ejaculatório. A morfologia dos espermatozóides revelou a presença de polimorfismo relacionado ao comprimento dos espermatozóides. Os eventos da espermiogênese nas espécies analisadas são similares e seguem o padrão descrito para outros grupos de insetos, sendo a diferenciação caracterizada pela formação do acrossoma e do ‘Nebenkern’, condensação do núcleo,alongamento celular incluindo desenvolvimento do flagelo e perda de citoplasma. A análise ultra estrutural revelou que o espermatozóide é formado por duas regiões -xiida cabeça e do flagelo, sendo a zona intermediária entre essas duas, denominada zona de justaposição “overlap”. As organelas presentes na região da cabeça são aocrossoma e o núcleo, e na região do flagelo o axonema (9+9+2), os derivados mitocondriais e o adjunto do centríolo. Foi observado a presença de polimorfismo relacionado à morfologia nas organelas que formam o espermatozóide. Algumas espécies possuem dois derivados mitocondriais e outras apenas um derivado. Oacrossoma nas três espécies do gênero Lucilia e nas duas espécies de Hemilucilia analisadas é cônico e volumoso, enquanto nas demais espécies é cônico e delgado.A marcação com ácido etanólico fosfotúngstico - EPTA mostrou-se diferente nas diferentes espécies analisadas. Foi avaliado ainda, o perfil de marcação de resíduos de carboidratos nas espermátides e nos espermatozóides das espécies presentes no Brasil, uma vez que tais moléculas são responsáveis, pelo reconhecimento e interação entre os gametas. O mapeamento dos carboidratos de superfície nos espermatozóides nos forneceu dados cito químicos importantes que, aliados aos dados morfológicos já existentes, poderão ser úteis em estudos taxonômicos. _______________________________________________________________________________ ABSTRACTMorphological data obtained from the analysis of the internal reproductive tractand from sperm in invertebrates have been increasingly used to provide consistent solutions to understand more fully the evolutionary history of the groups, because the traditionally used morphological data have not been enough. The Calliphoridae familyis an example of this lack. Although knowledge about this family is crucial tounder standing evolution within the Oestroidea group, until now little is known aboutthe internal morphology of its reproductive organs and its sperm. The current thesisevaluated the sperm morphology in 12 species of Calliphoridae, nine of which occurin Brazil and three in the Colombian Andes. Structurally, the male internalreproductive apparatus in Calliphoridae is formed by a pair of testicles, deferentducts and accessory glands, a seminal vesicle and an ejaculatory duct. Spermmorphology revealed the presence of polymorphism related to their length. In thespecies studied, the spermatogenesis events are similar and follow the patterndescribed for other groups of insects, with differentiation being characterized by theformation of the acrosome and the “Nebenkern”, condensation of the nucleus, cellularlengthening including flagellum development, and loss of cytoplasm. Ultrastructuralanalysis revealed that the sperm is made up of two regions – the head and theflagellum, with the intermediate zone between the two being denominated theoverlap. The organelles present in the head region are the acrosome and thenucleus, and in the flagellum there is the axoneme (9+9+2), the mitochondrialderivatives and the centriolar adjunct. The presence of polymorphism was observed,xivrelated to the morphology of the organelles that form the sperm. Some speciespossess two mitochondrial derivatives and others only one. The acrosome in thethree species from the genus Lucilia and in the two species of Hemilucilia analyzed isconical and bulky, while in the other species it is conical and slender. Marking withethanolic phosphotungstic acid (EPTA) was seen to be different for the variousspecies analyzed. The profile of carbohydrate residue marking in the spermatids andsperm was also evaluated for the species present in Brazil, because these moleculesare responsible,for recognition and interaction among gametes. Mapping the surfacecarbohydrates in the sperm provided us with important cyto-chemical data which,together with the morphological data that already exist, may be useful in taxonomicstudies
Rita Sinka - One of the best experts on this subject based on the ideXlab platform.
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testis specific bb8 is essential in the development of spermatid mitochondria
PLOS ONE, 2016Co-Authors: Viktor Vedelek, Attila L Kovacs, Gabor Juhasz, Barbara Laurinyecz, Rita SinkaAbstract:Mitochondria are essential organelles of developing spermatids in Drosophila, which undergo dramatic changes in size and shape after meiotic division, where mitochondria localized in the cytoplasm, migrate near the nucleus, aggregate, fuse and create the Nebenkern. During spermatid elongation the two similar mitochondrial derivatives of the Nebenkern start to elongate parallel to the axoneme. One of the elongated mitochondrial derivatives starts to lose volume and becomes the minor mitochondrial derivative, while the other one accumulates paracrystalline and becomes the major mitochondrial derivative. Proteins and intracellular environment that are responsible for cyst elongation and paracrystalline formation in the major mitochondrial derivative need to be identified. In this work we investigate the function of the testis specific big bubble 8 (bb8) gene during spermatogenesis. We show that a Minos element insertion in bb8 gene, a predicted glutamate dehydrogenase, causes recessive male sterility. We demonstrate bb8 mRNA enrichment in spermatids and the mitochondrial localisation of Bb8 protein during spermatogenesis. We report that megamitochondria develop in the homozygous mutant testes, in elongating spermatids. Ultrastructural analysis of the cross section of elongated spermatids shows enlarged mitochondria and the production of paracrystalline in both major and minor mitochondrial derivatives. Our results suggest that the Bb8 protein and presumably glutamate metabolism has a crucial role in the normal development and establishment of the identity of the mitochondrial derivatives during spermatid elongation.
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Normal mitochondrial development before spermatid elongation.
2016Co-Authors: Viktor Vedelek, Attila L Kovacs, Gabor Juhasz, Barbara Laurinyecz, Rita SinkaAbstract:(A-B) Primary spermatocytes have normal mitochondria, stained with Mitotracker in WT (A) and bb8ms (B) mutants. (C-F’) Development of Nebenkern in bb8ms mutant (D, F) is normal, similar to WT (C, E) by phase contrast microscopy and mitochondrial sensitive Mitotracker staining in post-meiotic onion stage spermatids (E’, F’). Scale bars: 5 μm. (G-H) Mitochondria of elongated spermatids are decorated by DJ-GFP in WT (G), but not in bb8ms mutants (H). Nuclei stained with DAPI. Scale bars: 200 μm.
Giorgio Prantera - One of the best experts on this subject based on the ideXlab platform.
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Nuclear lamina behavior during solofuso mutant meiotic and postmeiotic stages.
2016Co-Authors: Fabiana Fabbretti, Ilaria Iannetti, Loredana Guglielmi, Susanna Perconti, Chiara Evangelistella, Luca Proietti De Santis, Silvia Bongiorni, Giorgio PranteraAbstract:DNA in red (DAPI staining), nuclear lamina in green (anti Lam-Dm0). solofuso mutant males show chromatin bridges at (a) Anaphase I (arrowheads) and (b) Telophase I (arrowheads). NL shows an irregular signal at nuclear rim and a punctuated pattern over the chromatin bridges (a and b, arrowheads). Note that NL encircles the micronucleus (b, arrows). (c) Spermatids at onion stage evidencing a micronucleus surrounded by NL. (d) Onion stages showing a Nebenkern (Nb) associated to a nucleus (N) and two Nebenkern not associated with nuclei (d, DNA, arrows). The NL signal is detected around the nucleus associated with Nebenkern while no structured NL is present close to the Nebenkern lacking nuclei (d, LAMINA). Scale bar 20 μm.
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Nuclear lamina distribution during spermatids differentiation.
2016Co-Authors: Fabiana Fabbretti, Ilaria Iannetti, Loredana Guglielmi, Susanna Perconti, Chiara Evangelistella, Luca Proietti De Santis, Silvia Bongiorni, Giorgio PranteraAbstract:DNA in red (DAPI staining), nuclear lamina in green (anti Lam-Dm0). (a) T1 and T2 stages are characterized by the progressive aggregation of mitochondria into masses of different shapes. NL exhibits a punctuated pattern at the nuclear rim. (b) At onion stage nucleus and Nebenkern (DAPI staining, short and long arrows, respectively), in a 1:1 ratio, have the same round shape and size. NL shows a thick appearance at nuclear periphery, with interruptions (LAMINA staining, arrowheads). (c) T5 spermatid stage is characterized by an oval shaped Nebenkern (DAPI staining, arrows) with NL signal localized also inside the nuclei (c, LAMINA staining and merge). Scale bar 20 μm.
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Nuclear lamina distribution during the spermatid elongation.
2016Co-Authors: Fabiana Fabbretti, Ilaria Iannetti, Loredana Guglielmi, Susanna Perconti, Chiara Evangelistella, Luca Proietti De Santis, Silvia Bongiorni, Giorgio PranteraAbstract:DNA in red (DAPI staining), nuclear lamina in green (anti Lam-Dm0). Note the “half moon” configuration of NL that localizes from the same nuclear side of the elongating Nebenkern (arrows). Scale bar 20 μm.
Viktor Vedelek - One of the best experts on this subject based on the ideXlab platform.
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testis specific bb8 is essential in the development of spermatid mitochondria
PLOS ONE, 2016Co-Authors: Viktor Vedelek, Attila L Kovacs, Gabor Juhasz, Barbara Laurinyecz, Rita SinkaAbstract:Mitochondria are essential organelles of developing spermatids in Drosophila, which undergo dramatic changes in size and shape after meiotic division, where mitochondria localized in the cytoplasm, migrate near the nucleus, aggregate, fuse and create the Nebenkern. During spermatid elongation the two similar mitochondrial derivatives of the Nebenkern start to elongate parallel to the axoneme. One of the elongated mitochondrial derivatives starts to lose volume and becomes the minor mitochondrial derivative, while the other one accumulates paracrystalline and becomes the major mitochondrial derivative. Proteins and intracellular environment that are responsible for cyst elongation and paracrystalline formation in the major mitochondrial derivative need to be identified. In this work we investigate the function of the testis specific big bubble 8 (bb8) gene during spermatogenesis. We show that a Minos element insertion in bb8 gene, a predicted glutamate dehydrogenase, causes recessive male sterility. We demonstrate bb8 mRNA enrichment in spermatids and the mitochondrial localisation of Bb8 protein during spermatogenesis. We report that megamitochondria develop in the homozygous mutant testes, in elongating spermatids. Ultrastructural analysis of the cross section of elongated spermatids shows enlarged mitochondria and the production of paracrystalline in both major and minor mitochondrial derivatives. Our results suggest that the Bb8 protein and presumably glutamate metabolism has a crucial role in the normal development and establishment of the identity of the mitochondrial derivatives during spermatid elongation.
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Normal mitochondrial development before spermatid elongation.
2016Co-Authors: Viktor Vedelek, Attila L Kovacs, Gabor Juhasz, Barbara Laurinyecz, Rita SinkaAbstract:(A-B) Primary spermatocytes have normal mitochondria, stained with Mitotracker in WT (A) and bb8ms (B) mutants. (C-F’) Development of Nebenkern in bb8ms mutant (D, F) is normal, similar to WT (C, E) by phase contrast microscopy and mitochondrial sensitive Mitotracker staining in post-meiotic onion stage spermatids (E’, F’). Scale bars: 5 μm. (G-H) Mitochondria of elongated spermatids are decorated by DJ-GFP in WT (G), but not in bb8ms mutants (H). Nuclei stained with DAPI. Scale bars: 200 μm.
Fabiana Fabbretti - One of the best experts on this subject based on the ideXlab platform.
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Nuclear lamina behavior during solofuso mutant meiotic and postmeiotic stages.
2016Co-Authors: Fabiana Fabbretti, Ilaria Iannetti, Loredana Guglielmi, Susanna Perconti, Chiara Evangelistella, Luca Proietti De Santis, Silvia Bongiorni, Giorgio PranteraAbstract:DNA in red (DAPI staining), nuclear lamina in green (anti Lam-Dm0). solofuso mutant males show chromatin bridges at (a) Anaphase I (arrowheads) and (b) Telophase I (arrowheads). NL shows an irregular signal at nuclear rim and a punctuated pattern over the chromatin bridges (a and b, arrowheads). Note that NL encircles the micronucleus (b, arrows). (c) Spermatids at onion stage evidencing a micronucleus surrounded by NL. (d) Onion stages showing a Nebenkern (Nb) associated to a nucleus (N) and two Nebenkern not associated with nuclei (d, DNA, arrows). The NL signal is detected around the nucleus associated with Nebenkern while no structured NL is present close to the Nebenkern lacking nuclei (d, LAMINA). Scale bar 20 μm.
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Nuclear lamina distribution during spermatids differentiation.
2016Co-Authors: Fabiana Fabbretti, Ilaria Iannetti, Loredana Guglielmi, Susanna Perconti, Chiara Evangelistella, Luca Proietti De Santis, Silvia Bongiorni, Giorgio PranteraAbstract:DNA in red (DAPI staining), nuclear lamina in green (anti Lam-Dm0). (a) T1 and T2 stages are characterized by the progressive aggregation of mitochondria into masses of different shapes. NL exhibits a punctuated pattern at the nuclear rim. (b) At onion stage nucleus and Nebenkern (DAPI staining, short and long arrows, respectively), in a 1:1 ratio, have the same round shape and size. NL shows a thick appearance at nuclear periphery, with interruptions (LAMINA staining, arrowheads). (c) T5 spermatid stage is characterized by an oval shaped Nebenkern (DAPI staining, arrows) with NL signal localized also inside the nuclei (c, LAMINA staining and merge). Scale bar 20 μm.
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Nuclear lamina distribution during the spermatid elongation.
2016Co-Authors: Fabiana Fabbretti, Ilaria Iannetti, Loredana Guglielmi, Susanna Perconti, Chiara Evangelistella, Luca Proietti De Santis, Silvia Bongiorni, Giorgio PranteraAbstract:DNA in red (DAPI staining), nuclear lamina in green (anti Lam-Dm0). Note the “half moon” configuration of NL that localizes from the same nuclear side of the elongating Nebenkern (arrows). Scale bar 20 μm.
