Microstructure of Female Reproductive System of Phenacoccus fraxinus Tang (Hemiptera: Coccoidea: Pseudococcidae)

2008 ◽  
Vol 43 (4) ◽  
pp. 362-372 ◽  
Author(s):  
Xiaohong Fu ◽  
Yingping Xie ◽  
Xiaomin Zhang ◽  
Weimin Liu
Keyword(s):  
Electron Microscopy ◽  
Reproductive System ◽  
Lipid Droplets ◽  
Nurse Cells ◽  
Serial Sections ◽  
Female Reproductive System ◽  
Follicular Cells ◽  
Yolk Lipid ◽  
Egg Chamber ◽  
Scanning Electron

The structure of the female reproductive system of the mealybug, Phenacoccus fraxinus Tang (Hemiptera: Coccoidea: Pseudococcidae), was studied using standard histological examination of serial sections of tissues embedded in paraffin and by scanning electron microscopy. Our studies revealed that the ovary of P. fraxinus has paired lateral oviducts comprised of numerous short ovarioles. Each ovariole consists of 1 trophic chamber, 1 egg chamber and 1 pedicel which connect to the bottom of the egg chamber. Three nurse cells were observed in the trophic chamber, whereas yolk, lipid droplets and an oocyte were seen in the egg chamber. Follicular cells were arranged along the wall of the egg chamber and extended to form the pedicel. Many tracheae and tracheoles of various thicknesses were observed innervating the clusters of ovaries.

Embryogenesis and the first-stage larva of Thelazia lacrymalis

2003 ◽  
Vol 77 (3) ◽  
pp. 227-233 ◽  
Author(s):  
H. Dongus ◽  
P. Beelitz ◽  
H. Schöl
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Reproductive System ◽  
Distal Part ◽  
Developmental Stages ◽  
Nematode Species ◽  
Stage Larva ◽  
Female Reproductive System ◽  
Egg Membrane ◽  
Scanning Electron

AbstractThe female reproductive system of Thelazia lacrymalis (Nematoda: Thelaziidae) was investigated by light and scanning electron microscopy (SEM) with regard to the developmental stages and the stage deposited by the gravid nematode. Female T. lacrymalis have a didelphic and opisthodelphic type of reproductive system with paired ovaries, oviducts and uteri and a single vagina and vulva. Round and spindle-shaped primary oocytes are documented within the ovaries and oviducts, respectively. The distal part of each uterus provides a fertilization chamber filled with spermatozoa, followed by a sphincter-like part. Further anterior, the uteri broaden gradually containing dividing zygotes, small and large morulae, tadpole-stage embryos and horseshoe-shaped embryos which increase in length and become slimmer forming pretzel-stage embryos and larvae rolled up. The larvae stretch gradually and finally lie straight but still covered with their egg membrane in the vagina. The egg membrane encloses the whole larva and is enlarged at the pointed tail of the larva forming a bulb. At the SEM level, the first-stage larva is shown to have a terminal mouth and three hooks directed posteriorly and a striated cuticle. As morphologically identical larvae were also found in lavages of the conjunctival sac of horses infected with T. lacrymalis, this nematode species can be described as ovoviviparous.

scholarly journals Anatomical basis for cell transplantation into mouse seminiferous tubules

Reproduction ◽  
2012 ◽  
Vol 144 (3) ◽  
pp. 385-392 ◽  
Author(s):  
Unai Silván ◽  
Juan Aréchaga
Keyword(s):  
Electron Microscopy ◽  
Cell Transplantation ◽  
Soft Tissues ◽  
Partial Information ◽  
Three Dimensional ◽  
Seminiferous Tubules ◽  
Serial Sections ◽  
Pathological Conditions ◽  
Anatomical Basis ◽  
Scanning Electron

Cell transplantation into the seminiferous tubules is a useful technique for the study of physiological and pathological conditions affecting the testis. However, the precise three-dimensional organization and, particularly, the complex connectivity of the seminiferous network have not yet been thoroughly characterized. To date, the technical approaches to address these issues have included manual dissection under the stereomicroscope, reconstruction of histological serial sections, and injection of contrast dyes, but all of them have yielded only partial information. Here, using an approach based on the microinjection of a self-polymerizing resin followed by chemical digestion of the surrounding soft tissues, we reveal fine details of the seminiferous tubule scaffold and its connections. These replicas of the testis seminiferous network were studied by scanning electron microscopy. The present results not only establish a morphological basis for more precise microinjection into the mouse seminiferous tubules but also enable a more profound investigation of physiological and embryological features of the testis.

scholarly journals Ovary Structure and Oogenesis of Trypophloeus klimeschi (Coleoptera: Curculionidae: Scolytinae)

Insects ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1099
Author(s):  
Jing Gao ◽  
Jiaxing Wang ◽  
Hui Chen
Keyword(s):  
Electron Microscopy ◽  
Reproductive System ◽  
Secretory Cells ◽  
Female Reproductive System ◽  
Transition Stage ◽  
Accessory Glands ◽  
Transmission Electron ◽  
Secondary Stage ◽  
Terminal Filament ◽  
Structure And Ultrastructure

The female reproductive system, ovary structure and ultrastructure of Trypophloeus klimeschi (Coleoptera: Curculionidae: Scolytinae) were investigated using light microscopy, scanning electron microscopy, and transmission electron microscopy. Its female reproductive system is comprised of two ovaries (each ovary has two ovarioles), lateral oviducts, common oviduct, spermathecal sac, spermathecal pump, two accessory glands and bursa copulatrix. Well-developed endoplasmic reticulum can be clearly seen in the secretory cells of spermathecal sac. This species has telotrophic meroistic ovarioles that are comprised of terminal filament, tropharium, vitellarium and pedicel. The terminal filaments are simple; each is comprised of cellular peritoneal sheath. The presence of several clusters of nurse cells in the tropharium is indicative that its ovarioles conform to the transition stage. This indicates that there are at least two different types (transition stage and secondary stage) of ovarioles in Curculionidae.

Observations on changes in the female reproductive system of the wheat bulb fly Leptohylemyia coarctata (Fall.)

1971 ◽  
Vol 61 (1) ◽  
pp. 55-68 ◽  
Author(s):  
Margaret G. Jones
Keyword(s):  
Winter Wheat ◽  
Reproductive System ◽  
Follicular Epithelium ◽  
Cereal Aphids ◽  
Nurse Cells ◽  
Female Reproductive System ◽  
Egg Development ◽  
Sugar Water ◽  
The Third ◽  
Water Traps

In Leptohylemyia coarctata (Fall.) the germarium cuts off oocytes which develop through the stages 00 and 0 and I-V, recognised in other Cyclorraphous flies, in 4–5 weeks. All eggs of one batch of the gonadotrophic cycle ripen at the same time. After oviposition, the split intima, the remains of the follicular epithelium, and the nurse cells slowly contract to form the follicular relic. Flies swept from winter wheat during June and July and caught in water traps in July and August showed all stages of egg development. In 1970, 24·7% of the females swept from the crop had completed the first, 4–7% the second and 0–4% the third gonadotrophic cycle. All the eggs were not laid at the same time. During later gonadotrophic cycles, some ovarioles were non-functional. Flies laid one or two batches of eggs, rarely three. In 1970, many flies were attacked and killed by E. muscae. Only one out of 115 newly emerged female wheat bulb flies presented with foods usually found in the crop or citrated blood contained mature eggs after 24–27 days in small cages. Those fed only on 0·1 M glucose survived but did not deposit yolk in the ovum; those provided only with yeast paste died. Honey dew from cereal aphids was the main source of sugar. Water in droplet form and space to move seem necessary for the maturation of the eggs.

scholarly journals Origins of Enterovirus Replication Organelles Established by Whole-Cell Electron Microscopy

mBio ◽  
2019 ◽  
Vol 10 (3) ◽  
Author(s):  
Charlotte E. Melia ◽  
Christopher J. Peddie ◽  
Anja W. M. de Jong ◽  
Eric J. Snijder ◽  
Lucy M. Collinson ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Lipid Droplets ◽  
Genome Replication ◽  
Cellular Membranes ◽  
Whole Cell ◽  
Golgi Membranes ◽  
Face Scanning ◽  
Block Face ◽  
Scanning Electron

ABSTRACTEnterovirus genome replication occurs at virus-induced structures derived from cellular membranes and lipids. However, the origin of these replication organelles (ROs) remains uncertain. Ultrastructural evidence of the membrane donor is lacking, suggesting that the sites of its transition into ROs are rare or fleeting. To overcome this challenge, we combined live-cell imaging and serial block-face scanning electron microscopy of whole cells to capture emerging enterovirus ROs. The first foci of fluorescently labeled viral protein correlated with ROs connected to the endoplasmic reticulum (ER) and preceded the appearance of ROs stemming from thetrans-Golgi network. Whole-cell data sets further revealed striking contact regions between ROs and lipid droplets that may represent a route for lipid shuttling to facilitate RO proliferation and genome replication. Our data provide direct evidence that enteroviruses use ER and then Golgi membranes to initiate RO formation, demonstrating the remarkable flexibility with which enteroviruses usurp cellular organelles.IMPORTANCEEnteroviruses are causative agents of a range of human diseases. The replication of these viruses within cells relies on specialized membranous structures termed replication organelles (ROs) that form during infection but whose origin remains elusive. To capture the emergence of enterovirus ROs, we use correlative light and serial block-face scanning electron microscopy, a powerful method to pinpoint rare events in their whole-cell ultrastructural context. RO biogenesis was found to occur first at ER and then at Golgi membranes. Extensive contacts were found between early ROs and lipid droplets (LDs), which likely serve to provide LD-derived lipids required for replication. Together, these data establish the dual origin of enterovirus ROs and the chronology of their biogenesis at different supporting cellular membranes.

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