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1.
An. acad. bras. ciênc ; 90(1): 385-400, Mar. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886879

RESUMO

ABSTRACT The aim of this study was to evaluate somatic embryogenesis in juvenile explants of the THB papaya cultivar. Apical shoots and cotyledonary leaves were inoculated in an induction medium composed of different concentrations of 2,4-D (6, 9, 12, 15 and 18 µM) or 4-CPA (19, 22, 25, 28 and 31 µM). The embryogenic calluses were transferred to a maturation medium for 30 days. Histological analysis were done during the induction and scanning electron microscopy after maturing. For both types of auxin, embryogenesis was achieved at higher frequencies with cotyledonary leaves incubated in induction medium than with apical shoots; except for callogenesis. The early-stage embryos (e.g., globular or heart-shape) predominated. Among the auxins, best results were observed in cotyledonary leaves induced with 4-CPA (25 µM). Histological analyses of the cotyledonary leaf-derived calluses confirmed that the somatic embryos (SEs) formed from parenchyma cells, predominantly differentiated via indirect and multicellular origin and infrequently via synchronized embryogenesis. The secondary embryogenesis was observed during induction and maturation phases in papaya THB cultivar. The combination of ABA (0.5 µM) and AC (15 g L-1) in maturation medium resulted in the highest somatic embryogenesis induction frequency (70 SEs callus-1) and the lowest percentage of early germination (4%).


Assuntos
Brotos de Planta/fisiologia , Carica/embriologia , Carica/fisiologia , Técnicas de Embriogênese Somática de Plantas/métodos , Ácidos Indolacéticos/análise , Reguladores de Crescimento de Plantas/farmacologia , Microscopia Eletrônica de Varredura , Ácido Abscísico/farmacologia , Brotos de Planta/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Germinação/efeitos dos fármacos , Germinação/fisiologia , Meios de Cultura , Carica/anatomia & histologia , Carica/efeitos dos fármacos
2.
An Acad Bras Cienc ; 90(1): 385-400, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29424391

RESUMO

The aim of this study was to evaluate somatic embryogenesis in juvenile explants of the THB papaya cultivar. Apical shoots and cotyledonary leaves were inoculated in an induction medium composed of different concentrations of 2,4-D (6, 9, 12, 15 and 18 µM) or 4-CPA (19, 22, 25, 28 and 31 µM). The embryogenic calluses were transferred to a maturation medium for 30 days. Histological analysis were done during the induction and scanning electron microscopy after maturing. For both types of auxin, embryogenesis was achieved at higher frequencies with cotyledonary leaves incubated in induction medium than with apical shoots; except for callogenesis. The early-stage embryos (e.g., globular or heart-shape) predominated. Among the auxins, best results were observed in cotyledonary leaves induced with 4-CPA (25 µM). Histological analyses of the cotyledonary leaf-derived calluses confirmed that the somatic embryos (SEs) formed from parenchyma cells, predominantly differentiated via indirect and multicellular origin and infrequently via synchronized embryogenesis. The secondary embryogenesis was observed during induction and maturation phases in papaya THB cultivar. The combination of ABA (0.5 µM) and AC (15 g L-1) in maturation medium resulted in the highest somatic embryogenesis induction frequency (70 SEs callus-1) and the lowest percentage of early germination (4%).


Assuntos
Carica/embriologia , Carica/fisiologia , Ácidos Indolacéticos/análise , Brotos de Planta/fisiologia , Técnicas de Embriogênese Somática de Plantas/métodos , Ácido Abscísico/farmacologia , Carica/anatomia & histologia , Carica/efeitos dos fármacos , Meios de Cultura , Germinação/efeitos dos fármacos , Germinação/fisiologia , Microscopia Eletrônica de Varredura , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Brotos de Planta/efeitos dos fármacos , Valores de Referência , Reprodutibilidade dos Testes , Fatores de Tempo
3.
PLoS One ; 7(11): e50255, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23226253

RESUMO

The epidermis of Ostariophysi fish is composed of 4 main cell types: epidermal cells (or filament containing cells), mucous cells, granular cells and club cells. The morphological analysis of the epidermis of the catfish Pimelodella lateristriga revealed the presence of only two types of cells: epidermal and club cells. The latter were evident in the middle layer of the epidermis, being the largest cells within the epithelium. Few organelles were located in the perinuclear region, while the rest of the cytoplasm was filled with a non-vesicular fibrillar substance. Club cells contained two irregular nuclei with evident nucleoli and high compacted peripheral chromatin. Histochemical analysis detected prevalence of protein within the cytoplasm other than carbohydrates, which were absent. These characteristics are similar to those described to most Ostariophysi studied so far. On the other hand, the epidermal cells differ from what is found in the literature. The present study described three distinct types, as follows: superficial, abundant and dense cells. Differences among them were restricted to their cytoplasm and nucleus morphology. Mucous cells were found in all Ostariophysi studied so far, although they were absent in P. lateristriga, along with granular cells, also typical of other catfish epidermis. The preset study corroborates the observations on club cells' morphology in Siluriformes specimens, and shows important differences in epidermis composition and cell structure of P. lateristriga regarding the literature data.


Assuntos
Peixes-Gato/anatomia & histologia , Núcleo Celular/ultraestrutura , Citoplasma/ultraestrutura , Grânulos Citoplasmáticos/ultraestrutura , Epiderme/ultraestrutura , Células Epiteliais/ultraestrutura , Animais , Cromatina/ultraestrutura , Citoplasma/química , Citoesqueleto/ultraestrutura , Proteínas de Peixes/química , Histocitoquímica , Microscopia Eletrônica de Transmissão
4.
Micron ; 43(2-3): 292-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21963047

RESUMO

The male reproductive system of Mischocyttarus cassununga consists of two testes, each one with three follicles, as occurs in most Vespidae. The seminal vesicle is divided in two chambers, separated by a constriction, so that the anterior locus is a little larger. In the testicular follicles, the spermatozoa are organized in cysts, with approximately 128 per cyst, where the nuclei are oriented toward the follicle center. The spermatozoa of M. cassununga is about 97 µm in length, which makes them the shortest sperm described for Vespidae. Sperm ultrastructure of M. cassununga is very similar of the others Vespidae. But, despite these similarities, the bilobated mitochondrial derivative represents an autapomorphy for M. cassununga. The subdivision of the seminal vesicle has never been observed in any other Vespidae. Thus, this study supports the validity of insect sperm morphology as a tool for phylogenetic analysis within Hymenoptera.


Assuntos
Himenópteros/anatomia & histologia , Himenópteros/citologia , Animais , Genitália Masculina/anatomia & histologia , Genitália Masculina/citologia , Masculino , Mitocôndrias/ultraestrutura , Espermatozoides/citologia , Espermatozoides/ultraestrutura
5.
Arthropod Struct Dev ; 38(1): 54-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18675936

RESUMO

This study represents the first sperm description of a Vespinae species (Vespa crabro). The acrosome consists of an acrosomal vesicle and a perforatorium. The nucleus has compact chromatin and shows lenticular structures on the nuclear envelope. These structures, which have never been observed in a hymenopteran sperm, could be clusters of nuclear pores. The centriolar adjunct has an asymmetric pattern and shows a structured periphery. The centriole consists of 9 accessory microtubules and 9 doublet microtubules devoid of arms and spokes. The axoneme has a 9+9+2 microtubule pattern and the accessory microtubules have 16 protofilaments. The mitochondrial derivatives differ in length and diameter. The larger one is adjacent to the nuclear base, while the smaller one begins below the centriolar adjunct. They possess three distinct areas and a large paracrystalline region, which occurs only in the large one. The large mitochondrial derivative ends first, followed by the small one. The axoneme gradually disorganizes: first the central microtubules disappear, then the doublets, which show opened B-tubules, and finally the accessory microtubules. The sperm morphology of V. crabro is very similar to that of the polistine wasp, Agelaia vicina. This can indicate that, in Vespidae, sperm morphology is maintained without important variations among subfamilies and/or that this similarity indicates close phylogenetic relationship between these two subfamilies. Although Vespidae phylogenetically related to Formicidae, these data suggest that the former more closely related to Apoidea than to Formicidae.


Assuntos
Espermatozoides/ultraestrutura , Vespas/anatomia & histologia , Animais , Itália , Masculino , Microscopia Eletrônica de Transmissão , Microtomia
6.
Tissue Cell ; 40(3): 185-93, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18207210

RESUMO

In the seminal vesicle of the 'symphyta'Arge pagana the spermatozoa are stored in motile spermatodesm bundles, maintained by an anterior cap of extracellular material. This cap consists of a denser cortex and of an internal matrix, where part of the sperm heads are embedded. The number of spermatozoa per bundle is variable. The spermatozoa are short, only 30microm long, with a head region of about 23microm, and a very short flagellum of about 7microm. The head includes the acrosome, with a perforatorium, and the nucleus. The flagellum consists of an axoneme, with a 9+9+2 microtubule pattern, a centriolar adjunct, two mitochondrial derivatives and two accessory bodies. The mitochondrial derivatives are very slender and of different lengths. The longer begins at the base of the nucleus, while the shorter one starts just below the base of the centriolar adjunct. This latter is asymmetric and appears at the nuclear base, extending parallel to the axoneme up to the anterior end of the smaller mitochondrial derivative. The short spermatodesmata and the small mitochondrial derivatives characterize the A. pagana sperm. In addition, the centriolar adjunct asymmetry and the occurrence of spermatodesm bundles might be considered plesiomorphic states present in the basal Tenthredinoidea.


Assuntos
Himenópteros/ultraestrutura , Espermatozoides/ultraestrutura , Animais , Núcleo Celular/ultraestrutura , Polaridade Celular , Flagelos/ultraestrutura , Himenópteros/citologia , Masculino , Espermatozoides/citologia , Taninos
7.
Biocell ; 28(3): 299-310, dic. 2004. ilus
Artigo em Inglês | LILACS | ID: lil-405202

RESUMO

This study was undertaken to detect protein components in both sperm types of the butterfly Euptoieta hegesia. These spermatozoa possess complex extracellular structures for which the composition and functional significance are still unclear. In the apyrene sperm head, the proteic cap presented an external ring and an internal dense content; basic proteins were detected only in external portions. In the tail, the paracrystalline core of mitochondrial derivatives and the axoneme are rich in proteins. The extratesticular spermatozoa are covered by a proteic coat, which presented two distinct layers. In eupyrene spermatozoa, acrosome and nucleus were negatively stained, probably because of their high compaction. In the tail, there is no paracrystalline core and the axoneme presented a very specific reaction for basic proteins. The lacinate and reticular appendages are composed of cylindrical sub-units and presented a light reaction to E-PTA and a strong reaction to tannic acid. A complex proteic coat also covers the extratesticular spermatozoa. We found similarities between both extratesticular coats, indicating a possible common origin. Both spermatozoon types are rich in proteins, especially the eupyrene appendages and the extratesticular coats. We believe that both coats are related to the sperm maturation and capacitation processes.


Assuntos
Masculino , Animais , Espermátides/química , Espermatozoides/química , Borboletas/citologia , Borboletas/química , Borboletas/ultraestrutura , Proteínas de Insetos/análise , Acrossomo/química , Acrossomo/ultraestrutura , Centríolos/química , Centríolos/ultraestrutura , Cauda do Espermatozoide/química , Cauda do Espermatozoide/ultraestrutura , Espermátides/ultraestrutura , Espermatozoides/ultraestrutura , Núcleo Celular/química , Núcleo Celular/ultraestrutura , Coloração e Rotulagem , Testículo/citologia , Testículo/química , Ducto Deferente , Glândulas Seminais/citologia , Glândulas Seminais/química
8.
Biocell ; 28(3): 299-310, dic. 2004. ilus
Artigo em Inglês | BINACIS | ID: bin-1754

RESUMO

This study was undertaken to detect protein components in both sperm types of the butterfly Euptoieta hegesia. These spermatozoa possess complex extracellular structures for which the composition and functional significance are still unclear. In the apyrene sperm head, the proteic cap presented an external ring and an internal dense content; basic proteins were detected only in external portions. In the tail, the paracrystalline core of mitochondrial derivatives and the axoneme are rich in proteins. The extratesticular spermatozoa are covered by a proteic coat, which presented two distinct layers. In eupyrene spermatozoa, acrosome and nucleus were negatively stained, probably because of their high compaction. In the tail, there is no paracrystalline core and the axoneme presented a very specific reaction for basic proteins. The lacinate and reticular appendages are composed of cylindrical sub-units and presented a light reaction to E-PTA and a strong reaction to tannic acid. A complex proteic coat also covers the extratesticular spermatozoa. We found similarities between both extratesticular coats, indicating a possible common origin. Both spermatozoon types are rich in proteins, especially the eupyrene appendages and the extratesticular coats. We believe that both coats are related to the sperm maturation and capacitation processes. (AU)


Assuntos
Masculino , Animais , Mariposas/química , Mariposas/citologia , Mariposas/ultraestrutura , Proteínas de Insetos/análise , Espermátides/química , Espermatozoides/química , Acrossomo/química , Acrossomo/ultraestrutura , Núcleo Celular/química , Núcleo Celular/ultraestrutura , Centríolos/química , Centríolos/ultraestrutura , Glândulas Seminais/química , Glândulas Seminais/citologia , Cauda do Espermatozoide/química , Cauda do Espermatozoide/ultraestrutura , Espermátides/ultraestrutura , Espermatozoides/ultraestrutura , Coloração e Rotulagem , Testículo/química , Testículo/citologia , Ducto Deferente/citologia
9.
Biocell ; 28(3): 299-310, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15633453

RESUMO

This study was undertaken to detect protein components in both sperm types of the butterfly Euptoieta hegesia. These spermatozoa possess complex extracellular structures for which the composition and functional significance are still unclear. In the apyrene sperm head, the proteic cap presented an external ring and an internal dense content; basic proteins were detected only in external portions. In the tail, the paracrystalline core of mitochondrial derivatives and the axoneme are rich in proteins. The extratesticular spermatozoa are covered by a proteic coat, which presented two distinct layers. In eupyrene spermatozoa, acrosome and nucleus were negatively stained, probably because of their high compaction. In the tail, there is no paracrystalline core and the axoneme presented a very specific reaction for basic proteins. The lacinate and reticular appendages are composed of cylindrical sub-units and presented a light reaction to E-PTA and a strong reaction to tannic acid. A complex proteic coat also covers the extratesticular spermatozoa. We found similarities between both extratesticular coats, indicating a possible common origin. Both spermatozoon types are rich in proteins, especially the eupyrene appendages and the extratesticular coats. We believe that both coats are related to the sperm maturation and capacitation processes.


Assuntos
Borboletas/química , Proteínas de Insetos/análise , Espermátides/ultraestrutura , Espermatozoides/ultraestrutura , Acrossomo/química , Acrossomo/ultraestrutura , Animais , Borboletas/citologia , Borboletas/ultraestrutura , Núcleo Celular/química , Núcleo Celular/ultraestrutura , Centríolos/química , Centríolos/ultraestrutura , Masculino , Microscopia Eletrônica de Transmissão , Glândulas Seminais/química , Glândulas Seminais/citologia , Cauda do Espermatozoide/química , Cauda do Espermatozoide/ultraestrutura , Espermátides/química , Espermatozoides/química , Coloração e Rotulagem , Testículo/química , Testículo/citologia , Ducto Deferente/citologia
10.
Biocell ; 28(3): 299-310, 2004 Dec.
Artigo em Inglês | BINACIS | ID: bin-38509

RESUMO

This study was undertaken to detect protein components in both sperm types of the butterfly Euptoieta hegesia. These spermatozoa possess complex extracellular structures for which the composition and functional significance are still unclear. In the apyrene sperm head, the proteic cap presented an external ring and an internal dense content; basic proteins were detected only in external portions. In the tail, the paracrystalline core of mitochondrial derivatives and the axoneme are rich in proteins. The extratesticular spermatozoa are covered by a proteic coat, which presented two distinct layers. In eupyrene spermatozoa, acrosome and nucleus were negatively stained, probably because of their high compaction. In the tail, there is no paracrystalline core and the axoneme presented a very specific reaction for basic proteins. The lacinate and reticular appendages are composed of cylindrical sub-units and presented a light reaction to E-PTA and a strong reaction to tannic acid. A complex proteic coat also covers the extratesticular spermatozoa. We found similarities between both extratesticular coats, indicating a possible common origin. Both spermatozoon types are rich in proteins, especially the eupyrene appendages and the extratesticular coats. We believe that both coats are related to the sperm maturation and capacitation processes.

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