Sample records for OVOGENESIS (oogenesis)
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1

OVOGENESIS DE LUTJANUS PURPUREUS POEY, 1867 (PISCES: LUTJANIDAE) DE LA REGION ORIENTAL DE VENEZUELA/ OVOGENESIS OF LUTJANUS PURPUREUS POEY, 1867 (PISCES: LUTJANIDAE) IN EASTERN VENEZUELA

González, Leo W.; Lugo, Thais
1997-12-01

Resumen en español El presente trabajo tiene por objeto el estudio de la ovogénesis del pargo colorado, Lutjanus purpureus de la región oriental de Venezuela. El proceso de maduración de los ovarios comprende dos fases, previtelogénesis de tres estadios determinada por cambios en el núcleo y vitelogónesis de cuatro estadios caracterizada por la acumulación en el citoplasma de sustancias nutritivas representadas por vesículas, gránulos de vitelo y lípidos. El desarrollo ovárico es asincrónico reconociéndose diversos estadios típicos en los peces marinos tropicales. Resumen en inglés The purpose of this paper is the study of oogenesis in the red snapper, Lutjanus purpureus from the Venezuela eastern region. Bassed on histological descriptions the oogenesis is the egg development in ovaries and have two phases: Previtelogénesis of three stages characterized by changes in nucleus and Vitelogenesis have four stages distinguished by citoplasmatic accumulation of nutritive inclusions per yolk vesicles, oil droppets and yolk granules. The ovarian development is non syncrhonic typical the tropicals marines fishes.

Scientific Electronic Library Online (Spanish)

3

Ultrastructural studies of oogenesis in Bolinus brandaris (Gastropoda: Muricidae) | Estudio ultraestructural de la oogénesis de Bolinus brandaris (Gastropoda: Muricidae)

Amor, María José; Ramón, Montserrat; Durfort, Mercé

Ultrastructural studies of oogenesis in Bolinus brandaris are described. Although the initial phase of oogenesis is common to most animal species, vitellogenesis can be considered a species-specific characteristic. In the vitellogenesis of B.brandaris, mitochondria and endoplasmic reticula play a re...

DRIVER (Spanish)

4

Ultrastructural studies of oogenesis in Bolinus brandaris (Gastropoda: Muricidae)

Amor, María José; Ramón, Montserrat; Durfort, Mercè
2004-01-01

Digital.CSIC (Spain)

8

Polarization of both major body axes in Drosophila by gurken-torpedo signalling

González-Reyes, Acaimo; Elliott, Heather; St Johnston, Daniel
1995-06-22

Digital.CSIC (Spain)

9
10

Jak/Stat signalling in niche support cells regulates dpp transcription to control germline stem cell maintenance in the Drosophila ovary

López-Onieva, Lourdes; Fernández-Miñán, Ana; González-Reyes, Acaimo

8 pages, 5 figures.-- PMID: 18171682 [PubMed].-- Printed version published Feb 2008.-- Supporting information (Suppl. table S1, figure S1) available at: http://dev.biologists.org/cgi/content/full/135/3/533/DC1 | The existence of specialised regulatory microenvironments or niches that sustain stable ...

DRIVER (Spanish)

13

Histochemical characterisation of oocytes of the swordfish Xiphias gladius

Ortiz, Juan B.; Sarasquete, M.ª Carmen; Porcelloni, Serena; Fossi, Cristina
2008-01-01

Digital.CSIC (Spain)

15

Genetic dissection of a stem cell niche: the case of the Drosophila ovary

Bolívar, Jorge; Pearson, John; López-Onieva, Lourdes; González-Reyes, Acaimo

Final full-text version of the paper available at: http://dx.doi.org/10.1002/dvdy.20967.-- The Supplementary Material referred to in this article can be viewed at www.interscience.wiley.com/jpages/1058-8388/suppmat | In this work, we demonstrate a powerful new tool for the manipulation of the stroma...

DRIVER (Spanish)

16

Genetic dissection of a stem cell niche: the case of the Drosophila ovary

Bolívar, Jorge; Pearson, John; López-Onieva, Lourdes; González-Reyes, Acaimo
2006-11-01

Digital.CSIC (Spain)

17

Gametogenesis correlated with steroid levels during the gonadal cycle of the sea urchin Paracentrotus lividus (Echinodermata: Echinoidea)

Barbaglio, Alice; Sugni, Michela; Di Benedetto, Cristiano; Bonasoro, Francesco; Schnell, Sabine; Lavado Parra, Ramón; Porte Visa, Cinta; Candia Carnevali, Daniela M
2007-06-01

Digital.CSIC (Spain)

18

Functional Genomics and Proteomic Approaches for the Study of Gamete Formation and Viability in Farmed Finfish

Cerdà, Joan; Bobe, Julien; Babin, Patrick J.; Admon, Arie; Lubzens, Esther
2008-01-01

Digital.CSIC (Spain)

19

FERTILIDAD Y FECUNDIDAD DE MONTASTRAEA ANNULARIS EN UN ARRECIFE DEGRADADO/ FERTILITY AND FECUNDITY OF MONTASTREA ANNULARIS IN A DEGRADED REEF

Alvarado Ch., Elvira; Acosta, Alberto
2009-12-01

Resumen en español Este estudio determinó el ciclo gametogénico, fecundidad y fertilidad de Montastraea annularis en el arrecife de isla Grande, archipiélago de Nuestra Señora del Rosario, uno de los arrecifes más degradados del Caribe colombiano. La población de estudio se caracteriza por poseer colonias medianas (alrededor de 3379 cm²), con mortalidad parcial en 27 % de los ramets y total en el 10 % de los mismos. Las colonias presentan un alto número de ramets pequeños producto (mas) de la fisión (76 % menores a 50 cm²). Basado en las características de la estructura de tallas de la población mencionada, el objetivo de esta investigación fue explicar el bajo reclutamiento registrado en la zona, a través de la respuesta reproductiva de una población con dominancia de ramets pequeños. Entre septiembre de 2003 y septiembre de 2004, se tomaron muestras de tejido y se elaboraron placas histológicas para detallar el desarrollo gamético de oocitos y espermarios y cuantificar la fecundidad. Adicionalmente, durante septiembre de 2003 y 2004, se recolectaron huevos liberados in situ. Los resultados indicaron que la oogénesis ocurre entre mayo y septiembre y la espermatogénesis entre julio y septiembre. La fertilidad fue baja (35 % y 40 %, in situ e histología, respectivamente), así como la fecundidad (20 y 11 huevos/cm²/año-1, in situ e histología, respectivamente). De un 33 % de ramets que mostraron presencia de espermarios, sólo un 3 % de los mesenterios presentaron gametos masculinos y dentro de éstos, la presencia de los paquetes espermáticos también fue escasa (4 espermarios/gónada). Aunque la talla de los ramets no mostró una relación significativa con la fertilidad o la fecundidad, sí se observó que ramets entre 50 y 100 cm² eran más fecundos que los de tallas muy pequeñas ( 200 cm²). El pobre esfuerzo reproductivo observado puede, en parte, explicar, el bajo número de colonias pequeñas que exhibe la población estudiada, lo cual es esperado tanto para sitios degradados, como para poblaciones con alta tasa de fisión. Los resultados sugieren que la viabilidad de la población de M. annularis en isla Grande, está determinada por el bajo número de ramets fértiles y la baja fecundidad, pero especialmente por la escasa producción de gametos masculinos. Resumen en inglés This study determined the gametogenic cycle, fecundity and fertility of Montastraea annularis, in the Isla Grande coral reef, Archipelago of Nuestra Señora del Rosario, one of the most degraded reefs in the Colombian Caribbean. The surveyed population is currently characterized by medium size colonies (ca. 3379 cm²), with 27 % of the ramets showing partial mortality and 10 % with total mortality. Colonies present high number of small sized ramets formed by fission (76 % (mas) , smaller than 50 cm²). Based on the above mentioned population structure characteristics, the aim of this research was to explain the low recruitment rate reported for this reef through the reproductive response of a population dominated by small ramets. Between September 2003-2004, tissue fragments were collected and histological slides were made to detail the development of oocytes and spermaries and to estimate fecundity. Additionally during September of 2003 and 2004, in situ spawned eggs were collected to quantify fecundity. Results showed that oogenesis occurred between May and September and the spermatogenesis between July and September. Fertility was low (35 % and 40 %, in situ and histology, respectively) as well as fecundity (20 and 11 eggs/cm²/year-1, in situ and histology, respectively). Of the 33 % of ramets that showed spermaries, only 3 % of the mesenteries presented male gametes and in these, the presence of sperm cysts was also scarce (4 espermaries/gonad). Although the size of the ramets did not show a statistical relationship with fertility or fecundity, ramets between 50 and 100 cm² were found more fecund than smaller (200 cm²). The poor reproductive effort found can, in part, explain the low number of small colonies in the studied population, which in turn is expected in degraded sites and in populations with high fission rates. The results suggest that the viability of the population of M. annularis at Isla Grande is defined by the low number of fertile ramets and the low fecundity, but especially by low production of male gametes.

Scientific Electronic Library Online (Spanish)

20

Drosophila mus301/spindle-C Encodes a Helicase With an Essential Role in Double-Strand DNA Break Repair and Meiotic Progression

McCaffrey, Ruth; St Johnston, Daniel; González-Reyes, Acaimo

PMCID: PMC1667076 | mus301 was identified independently in two genetic screens, one for mutants hypersensitive to chemical mutagens and another for maternal mutants with eggshell defects. mus301 is required for the proper specification of the oocyte and for progression through meiosis in the Drosoph...

DRIVER (Spanish)

23

Criterios de nuliparidad y de paridad en Lutzomyia townsendi (Ortiz, 1959) del occidente de Venezuela

Márquez, Margarita; Scorza, José V.
1982-09-01

Resumen en español Lutzomyia townsendi (Ortiz, 1959) es un flebótomo antropofílico con concordancia gonadotrófica, en las zonas endémicas de Leishmania brasiliensis y L. garnhami en el occidente de Venezuela. Mediante el estudio de hembras colonizadas en el laboratorio, nuliparas o paridas, de hembras silvestres alimentadas sobre voluntarios y de hembras silvestres mantenidas con sacarosa, se establecen criterios de nuliparidad con un 56,6% de confianza. En cambio, signos de paridad apa (mas) recen en un 82% de las hembras consideradas como tales. La digestión de un ingesta sanguínea inicia un ciclo gonadotrófico con oogénesis abortiva y acumulación de fosfolípidos en las células epiteliales del estómago y en las glândulas accesorias. La ovoposición completa produce un calix ovárico grueso e irregular con restos de oocitos abortivos y acumulación de pigmentos. Estos caracteres son suficientes para precisar un criterio de paridad. La presencia de fosfolípidos en el estómago y en las glândulas accesorias de hembras nulíparas es una indicación de ingesta incompleta de sangre. Resumen en inglés Lutzomyia townsendi (Ortiz, 1959) is the main anthropophilic sandfly in endemic places for Leishmania braziliensis and L. garnhami in Western Venezuela. The study of laboratory bred females, nulliparous or parous and, wild females fed on man as well as wild females maintained with sucrose, allowed to establish a criterion of nulliparity with 56.6% of confidence for those captured in field conditions. In the same wild females, parity can be assessed with 81.5% of confidenc (mas) e. After blood digestion of full-engorged females a gonotrophic cycle is completed. Abortive oogenesis and accumulation of phospholipids in midgut epitelial cells and into accessory glands are observed. The ovoposition produces a thick and irregular ovaric calix with rests of abortive oocytes and accumulation of a melanin-like black pigment. All these changes are enough for identification of a parous fly. The presence of phospholipids in the stomach and accessory glands of a nulliparous sandfly is indicative of digestion of an incomplete blood meal.

Scientific Electronic Library Online (Spanish)

24

Changes in Cathepsin Gene Expression and Relative Enzymatic Activity During Gilthead Sea Bream Oogenesis

Carnevali, Oliana; Cionna, C.; Tosti, L.; Cerdà, Joan; Giocchini, G.
2007-05-30

Digital.CSIC (Spain)

25

Centrosome migration into the Drosophila oocyte is independent of BicD and egl, and of the organisation of the microtubule cytoskeleton

Bolívar, Jorge; Huynh, Jean-René; López-Schier, Hernán; González, Cayetano; St Johnston, Daniel; González-Reyes, Acaimo

During early Drosophila oogenesis, one cell from a cyst of 16 germ cells is selected to become the oocyte, and accumulates oocyte-specific proteins and the centrosomes from the other 15 cells. Here we show that the microtubule cytoskeleton and the centrosomes follow the same stepwise restriction to ...

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26

Centrosome migration into the Drosophila oocyte is independent of BicD and egl, and of the organisation of the microtubule cytoskeleton

Bolívar, Jorge; Huynh, Jean-René; López-Schier, Hernán; González, Cayetano; St Johnston, Daniel; González-Reyes, Acaimo
2001-04-19

Digital.CSIC (Spain)

27

Cell surface proteins Nasrat and Polehole stabilize the Torso-like extracellular determinant in Drosophila oogenesis

Jiménez, Gerardo; González-Reyes, Acaimo; Casanova, Jordi

PMCID: PMC152353 | Structural cell-surface and extracellular-matrix proteins modulate intercellular signaling events during development, but how this is achieved remains largely unknown. Here we identify a novel family of Drosophila proteins, Nasrat and Polehole, that coat the oocyte surface and pla...

DRIVER (Spanish)

29

Biochemical parameters during reproduction of the toad fish, Halobatrachus didactylus (Schneider, 1801)

Rosety, Manuel; Blanco, Miguel; González de Canales, María Luisa; Grau, Amalia; Sarasquete, M.ª Carmen
1992-01-01

Digital.CSIC (Spain)

30

An improved and simplified terminology for reproductive classification in fishes

Brown-Peterson, Nancy; Lowerre-Barbieri, Sue K.; Macewicz, Beverly J.; Saborido-Rey, Fran; Tomkiewicz, Jonna; Wyanski, David
2007-07-11

Digital.CSIC (Spain)

31

A novel mutant phenotype implicates dicephalic in cyst formation in the Drosophila ovary

McCaffrey, Ruth; St Johnston, Daniel; González-Reyes, Acaimo

Final full-text version available at: http://dx.doi.org/10.1002/dvdy.20620.-- Published online 28 October 2005 in Wiley InterScience (www.interscience.wiley.com). | The establishment of polarity in Drosophila requires the correct specification of the oocyte in early stages of oogenesis, its position...

DRIVER (Spanish)

32

A novel mutant phenotype implicates dicephalic in cyst formation in the Drosophila ovary

McCaffrey, Ruth; St Johnston, Daniel; González-Reyes, Acaimo
2006-04-01

Digital.CSIC (Spain)