scholarly journals ORGANIZATION AND ACTIVITY IN THE PRE- AND POSTOVULATORY FOLLICLE OF NECTURUS MACULOSUS

1968 ◽  
Vol 39 (1) ◽  
pp. 1-34 ◽  
Author(s):  
R. G. Kessel ◽  
W. R. Panje
Keyword(s):  
Soluble Proteins ◽  
Follicle Cells ◽  
Frozen Sections ◽  
Steroid Biosynthesis ◽  
Electron Microscope Level ◽  
Oocyte Growth ◽  
Necturus Maculosus ◽  
Postovulatory Follicle ◽  
Layer Chromatography ◽  
Level Analysis

The established follicle envelope of Necturus maculosus consists of a layer of follicle cells (granulosa) surrounding the developing oocyte, a layer of theca comprised of connective tissue cells, fibers, and matrix, and a layer of serosal cells. The changes in shape and fine structure of these layers during differentiation accompanying oogenesis are described. The cells and capillaries of the follicle envelope are engaged in an extensive pinocytotic activity, the details of which are described. We used cytochemical techniques to analyze the activity of the follicle envelope with respect to lipid accumulation and alkaline phosphatase activity. Radioautographic results indicate that cells of the follicle envelope are capable of incorporating tritium-labeled uridine and amino acids at certain times during oocyte growth. A comparative analysis was made of the soluble proteins in follicle envelopes isolated from immature oocytes and of those in follicle envelopes isolated from nearly mature oocytes and in postovulatory follicles. After the oocyte is ovulated, the cells of the follicle envelope are converted into a postovulatory follicle. The cells of the postovulatory follicle undergo further differentiation resulting in their becoming actively engaged in the formation of a secretion, the details of which are described at the electron microscope level. Analysis of the postovulatory follicle by thin-layer chromatography and cytochemistry demonstrated the presence of a wide variety of lipid substances and the possible presence of steroid. That the postovulatory follicle may be engaged in steroid biosynthesis is also suggested by studies involving the demonstration of 3 ß-hydroxysteroid dehydrogenase activity with cytochemical techniques applied to frozen sections and to soluble proteins separated by gel electrophoresis.

Homozygous mutation of foxh1 arrests oogenesis causing infertility in female Nile tilapia†

2019 ◽  
Vol 102 (3) ◽  
pp. 758-769
Author(s):  
Wenjing Tao ◽  
Hongjuan Shi ◽  
Jing Yang ◽  
Hamidou Diakite ◽  
Thomas D Kocher ◽  
...  
Keyword(s):  
Phase Iii ◽  
Follicle Cells ◽  
Homozygous Mutation ◽  
Serum Estradiol ◽  
Oocyte Growth ◽  
Expression Of Genes ◽  
Estrogen Production ◽  
Estrogen Synthesis ◽  
Smad Protein ◽  
Estradiol 17Β

Abstract Foxh1, a member of fox gene family, was first characterized as a transcriptional partner in the formation of the Smad protein complex. Recent studies have shown foxh1 is highly expressed in the cytoplasm of oocytes in both tilapia and mouse. However, its function in oogenesis remains unexplored. In the present study, foxh1−/− tilapia was created by CRISPR/Cas9. At 180 dah (days after hatching), the foxh1−/− XX fish showed oogenesis arrest and a significantly lower GSI. The transition of oocytes from phase II to phase III and follicle cells from one to two layers was blocked, resulting in infertility of the mutant. Transcriptomic analysis revealed that expression of genes involved in estrogen synthesis and oocyte growth were altered in the foxh1−/− ovaries. Loss of foxh1 resulted in significantly decreased Cyp19a1a and increased Cyp11b2 expression, consistent with significantly lower concentrations of serum estradiol-17β (E2) and higher concentrations of 11-ketotestosterone (11-KT). Moreover, administration of E2 rescued the phenotypes of foxh1−/− XX fish, as indicated by the appearance of phase III and IV oocytes and absence of Cyp11b2 expression. Taken together, these results suggest that foxh1 functions in the oocytes to regulate oogenesis by promoting cyp19a1a expression, and therefore estrogen production. Disruption of foxh1 may block the estrogen synthesis and oocyte growth, leading to the arrest of oogenesis and thus infertility in tilapia.

scholarly journals Role of Bicaudal-D in patterning the Drosophila egg chamber in mid-oogenesis

Development ◽  
1996 ◽  
Vol 122 (11) ◽  
pp. 3577-3586 ◽  
Author(s):  
A. Swan ◽  
B. Suter
Keyword(s):  
Cell Migration ◽  
Nurse Cell ◽  
Germ Line ◽  
Follicle Cells ◽  
Oocyte Size ◽  
Hsp70 Promoter ◽  
Oocyte Growth ◽  
Drosophila Oogenesis ◽  
Specific Mrnas

The Bicaudal-D (Bic-D) gene is required early in Drosophila oogenesis for the differentiation of an oocyte from one of a cluster of 16 interconnected germarial cells. To analyze the role of Bic-D later in oogenesis, we have constructed Drosophila lines in which Bic-D expression is under the control of the hsp70 promoter. In these flies, Bic-D activity can be induced early in oogenesis, allowing an oocyte to be made. Then, by shifting females to non-inducing conditions, Bic-D levels are depleted for the remainder of oogenesis. Using this system, we find that Bic-D is indeed required in the later stages of oogenesis. In ovaries from mutant females, oocyte growth is reduced, apparently due to defects in nurse-cell-to-oocyte transport. Smaller oocyte size results in the misalignment of follicle cells and the underlying germ line, leading to ventralization of dorsal follicle cells and to defects in centripetal cell migration. In addition, we show that Bic-D is required for the localization of specific mRNAs at both the anterior and posterior of the oocyte.

scholarly journals The dynamics of postovulatory follicle degeneration and oocyte growth in Baltic sprat

2012 ◽  
Vol 67 (1) ◽  
pp. 27-33 ◽  
Author(s):  
H. Haslob ◽  
G. Kraus ◽  
F. Saborido-Rey
Keyword(s):  
Oocyte Growth ◽  
Postovulatory Follicle

scholarly journals Bidirectional communication between oocytes and follicle cells: ensuring oocyte developmental competence

2010 ◽  
Vol 88 (4) ◽  
pp. 399-413 ◽  
Author(s):  
Gerald M. Kidder ◽  
Barbara C. Vanderhyden
Keyword(s):  
Small Molecules ◽  
Developmental Competence ◽  
Follicle Cells ◽  
Paracrine Factors ◽  
Oocyte Growth ◽  
Gap Junction Channels ◽  
Oocyte Developmental Competence ◽  
Mammalian Oocyte ◽  
Activating Receptors ◽  
Bidirectional Communication

Female fertility is determined to a large extent by the quality (developmental competence) of the oocyte as reflected in its ability to undergo meiosis, be fertilized, and give rise to a healthy embryo. Growth of the mammalian oocyte is coordinated with that of the follicle that encloses it by the actions of signals that pass in both directions between the germline and somatic components. This review summarizes what is known about the roles played by 2 different modes of intrafollicular signalling in oogenesis: paracrine factors activating receptors on the opposite cell type, and direct sharing of small molecules throughout the follicle via gap junction channels. Recent evidence indicates that these 2 modes of signalling interact to regulate oocyte growth and granulosa cell proliferation and that defects in either can contribute to female infertility.

Cell–cell interaction and oocyte growth

Zygote ◽  
1994 ◽  
Vol 2 (4) ◽  
pp. 343-345 ◽  
Author(s):  
Rita Canipari
Keyword(s):  
Primordial Follicle ◽  
Cell Interaction ◽  
Follicle Cells ◽  
Fetal Life ◽  
Oocyte Growth ◽  
Diplotene Stage ◽  
Prophase I ◽  
Cell Cell

In most mammals, oocytes initiate meiosis in late fetal life; by the time of birthe they have already entered the diplotene stage of prophase I of meiosis and becaome arrested thereafter at the dictyate state(Baker, 1972). At this stage they became surrounded by a few nonproliferating flat follicle cells forming a unit called the resting or primordial follicle.

The differentiation and proliferation of follicle cells during oocyte growth in Lacerta sicula

Development ◽  
1979 ◽  
Vol 54 (1) ◽  
pp. 5-15
Author(s):  
S. Filosa ◽  
C. Taddei ◽  
P. Andreuccetti
Keyword(s):  
Small Cells ◽  
Follicle Cells ◽  
Follicular Epithelium ◽  
Oocyte Growth ◽  
Large Follicle ◽  
Differentiation And Proliferation ◽  
Pyriform Cells

The follicular epithelium of the lizard oocytes undergoes structural and morphological modifications throughout oocyte growth. During this process the number of follicle cells increases and the epithelium acquires a multilayered and polymorphic organization which is characterized by the appearance of large follicle cells (intermediate and pyriform cells). The number of large cells also increases during oocyte growth and this increase parallels that of small cells. However, only the small cells become labelled one hour after [3H-]thymidine administration. Large cells have been found labelled after a longer period of time, i.e. 4–5 months after isotope injection. All these results together indicate that large follicle cells arise from the differentiation of small cells.

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