WordNet

development of ova

English Journal

The female millipede reproductive system and its dynamical changes, with a partial review.

Warburg MR.Author information Department of Biology, Technion-Israel Institute of Technology, 32000 Haifa, Israel. warburg@tx.technion.ac.ilAbstractThe structure of the millipede female reproductive system is described, discussed and reviewed. The different reproductive systems of female millipedes are illustrated, some of them for the first time. The various families appear to have developed several different structures of this organ. Nevertheless, more detailed studies on the female reproductive systems, especially the changes taking place during the oogenetic cycle, are needed in all millipede orders. Only this way can it be ascertained, whether ovarian structures observed are not only a transitional phase. This was done in two millipedes, Archispirostreptus tumuliporus judaicus (Attems 1927) and Catamicrophyllum caifanum (Verhoeff 1900), where these changes were followed for a longer period of time and on a large number of specimens. The evolutionary meaning of this diversity in reproductive systems cannot be clarified at the present time, nor its significance for the survival of the such diversified forms in the Class Diplopoda.
Morphologie : bulletin de l'Association des anatomistes.Morphologie.2012 Aug;96(313):29-39. doi: 10.1016/j.morpho.2012.07.002. Epub 2012 Sep 25.
The structure of the millipede female reproductive system is described, discussed and reviewed. The different reproductive systems of female millipedes are illustrated, some of them for the first time. The various families appear to have developed several different structures of this organ. Neverthe
PMID 23017838

Cytoskeletal organization of bee ovarian follicles during oogenesis.

Patrício K1, da Cruz-Landim C, Machado-Santelli GM.Author information 1Department of Biology, Institute of Biosciences, UNESP - Univ. Estadual Paulista, 24 Av. N° 1515, CEP 13.506-900, Rio Claro, SP, Brazil.AbstractThe germ cells in the germarium of the bee meroistic polytrophic ovarian cysts remain interconnected by cytoplasmic bridges as a result of incomplete cell division. These intercellular bridges form a distribution pathway for the substances that initially determine which of the cystocytes will become oocyte and later conduct the products synthesized by the nurse cells to the oocyte. In the present work, the presence and distribution of cytoskeleton components, actin and tubulin were studied in ovaries of queens of Apis mellifera and Scaptotrigona postica, two eusocial species, using antibody against α- and β-tubulin and FITC-phalloidin, aiming to shed light on the role of these cytoskeleton elements in oogenesis. The immunofluorescent preparations were analyzed by laser scanning confocal microscopy. F-actin was detected in the intercellular bridges of both species. The tubulin distribution in cell cytoplasm of A. mellifera and S. postica also displayed similar pattern. The role of these elements in the oogenetic events responsible for both cell support and motility is discussed.
Micron (Oxford, England : 1993).Micron.2011 Jan;42(1):55-9. doi: 10.1016/j.micron.2010.08.002. Epub 2010 Aug 12.
The germ cells in the germarium of the bee meroistic polytrophic ovarian cysts remain interconnected by cytoplasmic bridges as a result of incomplete cell division. These intercellular bridges form a distribution pathway for the substances that initially determine which of the cystocytes will become
PMID 20850979

Do variable compensatory mechanisms explain the polymorphism of the dependence phenotype in the Asobara tabida-wolbachia association?

Kremer N1, Dedeine F, Charif D, Finet C, Allemand R, Vavre F.Author information 1Université de Lyon, Lyon, France. natacha.kremer@normalesup.orgAbstractWolbachia are symbiotic intracellular bacteria, which are classified as reproductive parasites. Although generally facultative, Wolbachia is necessary for Asobara tabida (Hymenoptera), because aposymbiotic females do not produce any offspring. Interestingly, the ovarian phenotype of aposymbiotic females is variable: some females do not produce any eggs, whereas others do produce some eggs, but these are aborted. Here, we show that the ovarian phenotype of aposymbiotic females is highly polymorphic within populations, although dependence remains complete in both cases. We also identified some lines in which aposymbiotic females were able to produce a very few viable offspring, further extending the range of variation observed. These results suggest that various factors actively maintain polymorphism. We demonstrated that Wolbachia is necessary to trigger oogenetic processes, but that the ovarian phenotype was determined by the host only. Phenotypic variation was also correlated with the differential expression of genes controlling iron homeostasis and oxidative stress, which are potentially involved in the evolution of dependence. This suggests that variation in the ovarian phenotype could reflect selection for different levels of compensatory mechanisms in response to Wolbachia infection, and that polymorphism is maintained through selection on different antagonist traits influenced by oxidative stress.
Evolution; international journal of organic evolution.Evolution.2010 Oct;64(10):2969-79. doi: 10.1111/j.1558-5646.2010.01034.x. Epub 2010 Aug 19.
Wolbachia are symbiotic intracellular bacteria, which are classified as reproductive parasites. Although generally facultative, Wolbachia is necessary for Asobara tabida (Hymenoptera), because aposymbiotic females do not produce any offspring. Interestingly, the ovarian phenotype of aposymbiotic fem
PMID 20482609

Japanese Journal

DIVERSITY AND UNIFORMITY IN OVARIAN SHAPES AND OOGENETIC MODES IN CHELICERATE ARTHROPODS(Taxonomy and Systematics,Abstracts of papers presented at the 74^<th> Annual Meeting of the Zoological Society of Japan)