scholarly journals PERMEABILITY OF THE OVARIAN FOLLICLE OF AEDES AEGYPTI MOSQUITOES

1971 ◽  
Vol 50 (1) ◽  
pp. 201-221 ◽  
Author(s):  
Winston A. Anderson ◽  
Andrew Spielman
Keyword(s):  
Aedes Aegypti ◽  
Ovarian Follicle ◽  
Vitelline Membrane ◽  
Tracer Studies ◽  
Molecular Weights ◽  
Mechanical Filter ◽  
Pinocytotic Vesicle ◽  
Basement Lamina ◽  
Intercellular Channels ◽  
Exogenous Compounds

The passage of tracers of various molecular weights into resting and vitellogenic ovarian follicles of Aedes aegypti mosquitoes was studied ultrastructurally. The outermost layer of the follicular sheath (the basement lamina) is a coarse mechanical filter. It is freely permeable to particles with molecular weights ranging from 12,000 to 500,000 (i.e. cytochrome c, peroxidase, hemoglobin, catalase, ferritin, immunoglobulin (IgG)-peroxidase, iron dextran and Thorotrast) that have dimensions less than 110 A. Molecules as large as carbon (300–500 A) are totally excluded. Whereas proteins and polysaccharide tracers permeate the basement lamina with apparent ease, certain inert particles (e.g. Thorotrast, Fellows-Testager Div., Fellows Mfg. Co., Inc., Detroit, Mich.) penetrate more slowly. With respect to the tracers tested, resting follicles are as permeable as vitellogenic follicles. The follicle epithelium of resting or vitellogenic follicles is penetrated by narrow intercellular channels. Our observations suggest that these spaces are lined with mucopolysaccharide material. After permeating the basement lamina, exogenous tracers fill these channels, while the bulk of material accumulates in the perioocytic space. Within 3 hr after imbibing blood, the pinocytotic mechanism of the oocyte is greatly augmented. Pinocytosis is not selective with regard to material in the perioocytic space, since double tracer studies show that exogenous compounds are not separated, but are incorporated into the same pinocytotic vesicle. During later stages of vitellogenesis, 36–48 hr after the blood-meal, the pinocytotic mechanism of the oocyte is diminished. Simultaneously, the intercellular channels become occluded by desmosomes, and the vitelline membrane plaques separate the oocyte and follicle epithelium.

Structure, Expression, and Hormonal Control of Genes from the Mosquito, Aedes aegypti, Which Encode Proteins Similar to the Vitelline Membrane Proteins of Drosophila melanogaster

1993 ◽  
Vol 155 (2) ◽  
pp. 558-568 ◽  
Author(s):  
Yonggu Lin ◽  
Martha T. Hamblin ◽  
Marten J. Edwards ◽  
Carolina Barillas-Mury ◽  
Michael R. Kanost ◽  
...  
Keyword(s):  
Drosophila Melanogaster ◽  
Membrane Proteins ◽  
Aedes Aegypti ◽  
Hormonal Control ◽  
Vitelline Membrane

Studies on the Ovarian Follicle Cells of Drosophila

1963 ◽  
Vol s3-104 (67) ◽  
pp. 297-320
Author(s):  
R. C. KING ◽  
ELIZABETH A. KOCH
Keyword(s):  
Ovarian Follicle ◽  
Protein A ◽  
Follicle Cell ◽  
Follicle Cells ◽  
Vitelline Membrane ◽  
Membrane Material ◽  
Adjacent Layer ◽  
Membrane Formation ◽  
Precursor Material ◽  
Egg Shell

Studies are described of the ultrastructure of the follicle cells which invest the oocyte of Drosophila melanogaster at the time of vitelline membrane formation. Of particular interest are organelles made up of endoplasmic reticulum organized into a husk of concentric lamellae which surround lipidal droplets. These epithelial bodies are seen only at the time the vitelline membrane is being formed, and it is assumed therefore that the lipidal material of the epithelial body may be utilized somehow in the fabrication of the vitelline membrane. Cytochemical studies have shown this membrane to contain at least 5 classes of compounds; a protein, two lipids (which may be distinguished by differences in their resistance to extraction by various solvents), and 2 polysaccharides (1 neutral and 1 acidic). Studies were made of vitelline membrane formation in the ovaries of flies homozygous for either of 2 recessive, female-sterile genes (tiny and female sterile). In the case of the ty mutation vitelline membrane material is sometimes secreted between follicle and nurse cells, while in the mutant fes vitelline membrane is observed in rare instances to be secreted between follicle cells and an adjacent layer of tumour cells. In the latter case the vitelline membrane shows altered cytochemical properties. The fact that vitelline membrane can be secreted by follicle cells not adjacent to an oocyte demonstrates that it is the follicle cell rather than the oocyte that plays the major role in the secretion of the precursor material of the vitelline membrane. Subsequently the follicle cells secrete the egg-shell, or chorion, which is subdivided into a dense, compartmented, inner endochorion, and a pale, outer exochorion. A description is given of the ultrastructure of the follicle cells during the secretion of the endochorion and the exochorion. The endochorion contains a protein, a polysaccharide, and a lipid, all of which may be distinguished cytochemically from the vitelline membrane compounds. The exochorion contains large amounts of acidic mucopolysaccharides. Specialized follicle cells form the micropylar apparatus and the chorionic appendages. The formation of the chorion and chorionic appendages is discussed in the light of information gained from abnormalities of the chorions and chorionic appendages seen in ty and fs 2.1 oocytes. Subsequent to the time the egg leaves the ovariole a layer of waterproofing wax is secreted between the vitelline membrane and the chorion.

scholarly journals PURIFIKASI PROTEIN IMUNOGENIK 31 DAN 56 kDa DARI KELENJAR SALIVA Aedes aegypti

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Syubbanul Wathon ◽  
Fitria Mutiah ◽  
Rike Oktarianti ◽  
Kartika Senjarini
Keyword(s):  
Salivary Gland ◽  
Aedes Aegypti ◽  
Positive Control ◽  
Protein Fractions ◽  
Immunogenic Protein ◽  
Dot Blot ◽  
Molecular Weights ◽  
Sds Page ◽  
Salivary Gland Protein ◽  
Immunogenic Proteins

Purification of 31 and 56 kDa Immunogenic Proteins from the Salivary Glands of Aedes aegyptiThe salivary gland of arthropod vector contains various bioactive compounds and plays a role in the transmission of pathogens to the host. The host develops anti-salivary antibodies against vector saliva exposure. Our previous research has identified two immunogenic proteins with molecular weights of 31 and 56 kDa from the Aedes aegypti salivary gland protein extract. However, the role of the 31 and 56 kDa immunogenic proteins from saliva Ae. aegypti is not fully known, so it is necessary to purify two immunogenic protein fractions to better specify the target of developing a dengue vaccine. This study aimed to purify the 31 and 56 kDa immunogenic protein fractions by electroelution and dialysis methods. The purification of the two protein fractions has been successful which were confirmed by the SDS-PAGE by the existence of single-band parallel to the positive control. These results were further supported by the dot blot analysis which showed a positive reaction in the form of dark spots in the two protein fractions which were reacted with dengue patients' serum, endemic healthy people, and neonates. These results indicated that the purified 31 and 56 kDa immunogenic protein fraction can be identified by specific antibodies.Keywords: dialysis, electroelution, immunogenic, purification, saliva  ABSTRAKKelenjar saliva vektor arthropoda mengandung berbagai senyawa bioaktif dan berperan dalam transmisi patogen ke tubuh inang. Tubuh inang mengembangkan antibodi anti-saliva terhadap paparan saliva vektor. Penelitian kami sebelumnya telah mengidentifikasi dua protein imunogenik dengan berat molekul 31 dan 56 kDa dari ekstrak protein kelenjar saliva Aedes aegypti. Namun demikian, peranan protein imunogenik 31 dan 56 kDa dari saliva Ae. aegypti belum diketahui sepenuhnya sehingga perlu dilakukan purifikasi dua fraksi protein imunogenik untuk lebih menspesifikkan target pengembangan vaksin dengue. Tujuan penelitian ini untuk melakukan purifikasi fraksi protein imunogenik 31 dan 56 kDa melalui metode elektroelusi dan dialisis. Keberhasilan purifikasi dua fraksi protein 31 dan 56 kDa terbukti dari hasil konfirmasi SDS-PAGE dengan terbentuknya pita tunggal sejajar dengan kontrol positif. Hasil tersebut diperkuat dengan analisis dot blot yang menunjukkan reaksi positif dengan munculnya noktah gelap pada dua fraksi protein tersebut ketika direaksikan dengan serum pasien DBD, penduduk sehat endemik dan neonatus. Hasil ini mengindikasikan bahwa fraksi protein imunogenik 31 dan 56 kDa hasil purifikasi dapat dikenali oleh antibodi spesifik.

Transmission Electron Microscopy of Protein Macromolecules

1971 ◽  
Vol 29 ◽  
pp. 424-425
Author(s):  
Henry S. Slayter
Keyword(s):  
Biological Systems ◽  
Metal Vapor ◽  
Resolving Power ◽  
Electron Microscopic ◽  
Chemical Methods ◽  
Molecular Weights ◽  
The Past ◽  
Physical Chemical ◽  
Transmission Electron

Electron microscopic methods have been applied increasingly during the past fifteen years, to problems in structural molecular biology. Used in conjunction with physical chemical methods and/or Fourier methods of analysis, they constitute powerful tools for determining sizes, shapes and modes of aggregation of biopolymers with molecular weights greater than 50, 000. However, the application of the e.m. to the determination of very fine structure approaching the limit of instrumental resolving power in biological systems has not been productive, due to various difficulties such as the destructive effects of dehydration, damage to the specimen by the electron beam, and lack of adequate and specific contrast. One of the most satisfactory methods for contrasting individual macromolecules involves the deposition of heavy metal vapor upon the specimen. We have investigated this process, and present here what we believe to be the more important considerations for optimizing it. Results of the application of these methods to several biological systems including muscle proteins, fibrinogen, ribosomes and chromatin will be discussed.

Characterization of microtubules by dark-field STEM and replication

1991 ◽  
Vol 49 ◽  
pp. 152-153
Author(s):  
S.B. Andrews ◽  
R.D. Leapman ◽  
P.E. Gallant ◽  
T.S. Reese
Keyword(s):  
Protein Interactions ◽  
Low Dose ◽  
Unit Length ◽  
Dark Field ◽  
Carbon Films ◽  
Microtubule Associated Proteins ◽  
Molecular Weights ◽  
Freeze Dried ◽  
Protein Motors ◽  
Associated Proteins

As part of a study on protein interactions involved in microtubule (MT)-based transport, we used the VG HB501 field-emission STEM to obtain low-dose dark-field mass maps of isolated, taxol-stabilized MTs and correlated these micrographs with detailed stereo images from replicas of the same MTs. This approach promises to be useful for determining how protein motors interact with MTs. MTs prepared from bovine and squid brain tubulin were purified and free from microtubule-associated proteins (MAPs). These MTs (0.1-1 mg/ml tubulin) were adsorbed to 3-nm evaporated carbon films supported over Formvar nets on 600-m copper grids. Following adsorption, the grids were washed twice in buffer and then in either distilled water or in isotonic or hypotonic ammonium acetate, blotted, and plunge-frozen in ethane/propane cryogen (ca. -185 C). After cryotransfer into the STEM, specimens were freeze-dried and recooled to ca.-160 C for low-dose (<3000 e/nm2) dark-field mapping. The molecular weights per unit length of MT were determined relative to tobacco mosaic virus standards from elastic scattering intensities. Parallel grids were freeze-dried and rotary shadowed with Pt/C at 14°.

Electron Microscope Study of RNA's of Paramyxoviruses

1972 ◽  
Vol 30 ◽  
pp. 196-197
Author(s):  
Ruchama Baum ◽  
J.T. Seto
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Electron Microscope Study ◽  
Sendai Virus ◽  
Sodium Dodecyl ◽  
Rna Molecules ◽  
Virus Particles ◽  
Molecular Weights ◽  
Length Measurements

The ribonucleic acid (RNA) of paramyxoviruses has been characterized by biochemical and physiochemical methods. However, paramyxovirus RNA molecules have not been studied by electron microscopy. The molecular weights of these single-stranded viral RNA molecules are not known as yet. Since electron microscopy has been found to be useful for the characterization of single-stranded RNA, this investigation was initiated to examine the morphology and length measurements of paramyxovirus RNA's.Sendai virus Z strain and Newcastle disease virus (NDV), Milano strain, were used. For these studies it was necessary to develop a method of extracting RNA molecules from purified virus particles. Highly purified Sendai virus was treated with pronase (300 μg/ml) at 37°C for 30 minutes and the RNA extracted by the sodium dodecyl sulfate (SDS)-phenol procedure.

Nucleic Acid Molecules Prepared by Monolayer Techniques

1972 ◽  
Vol 30 ◽  
pp. 178-179
Author(s):  
Dimitrij Lang
Keyword(s):  
Electron Microscopy ◽  
Standard Deviation ◽  
Nucleic Acid ◽  
Cytochrome C ◽  
Nucleic Acids ◽  
Contour Length ◽  
Sample Standard Deviation ◽  
Molecular Weights ◽  
Length Measurements ◽  
Protein Monolayer

The success of the protein monolayer technique for electron microscopy of individual DNA molecules is based on the prevention of aggregation and orientation of the molecules during drying on specimen grids. DNA adsorbs first to a surface-denatured, insoluble cytochrome c monolayer which is then transferred to grids, without major distortion, by touching. Fig. 1 shows three basic procedures which, modified or not, permit the study of various important properties of nucleic acids, either in concert with other methods or exclusively:1) Molecular weights relative to DNA standards as well as number distributions of molecular weights can be obtained from contour length measurements with a sample standard deviation between 1 and 4%.

Apoptosis during the development of ovarian follicle

2010 ◽  
Vol 34 (8) ◽  
pp. S10-S10
Author(s):  
Xuan Jin ◽  
Xiaojin Huang ◽  
Jing Zhang
Keyword(s):  
Ovarian Follicle
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