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FEMS Microbiology Reviews Jul 2009Salmonella Enteritidis (SE) has been the major cause of the food-borne salmonellosis pandemic in humans over the last 20 years, during which contaminated hen's eggs were... (Review)
Review
Salmonella Enteritidis (SE) has been the major cause of the food-borne salmonellosis pandemic in humans over the last 20 years, during which contaminated hen's eggs were the most important vehicle of the infection. Eggs can be contaminated on the outer shell surface and internally. Internal contamination can be the result of penetration through the eggshell or by direct contamination of egg contents before oviposition, originating from infection of the reproductive organs. Once inside the egg, the bacteria need to cope with antimicrobial factors in the albumen and vitelline membrane before migration to the yolk can occur. It would seem that serotype Enteritidis has intrinsic characteristics that allow an epidemiological association with hen eggs that are still undefined. There are indications that SE survives the attacks with the help of antimicrobial molecules during the formation of the egg in the hen's oviduct and inside the egg. This appears to require a unique combination of genes encoding for improved cell wall protection and repairing cellular and molecular damage, among others.
Topics: Animals; Chickens; Eggs; Female; Food Contamination; Salmonella Infections, Animal; Salmonella enteritidis; Virulence Factors
PubMed: 19207743
DOI: 10.1111/j.1574-6976.2008.00161.x -
The International Journal of... 2018This paper provides a brief account of some aspects of the career of Ruth Bellairs using selected examples from her research publications, with the emphasis being placed...
This paper provides a brief account of some aspects of the career of Ruth Bellairs using selected examples from her research publications, with the emphasis being placed on the early stages of chick embryo development, and in particular, on cell migration. Topics include the role of Hensen's node, the vitelline membrane, the structure and segmentation of somites, the tail bud and the Wolffian duct. Her research approach has involved embryo culture, experimental surgery, transmission and scanning electron microscopy, time-lapse filming and immunostaining techniques.
Topics: Animals; Cell Movement; Chick Embryo; Chickens; Embryo Culture Techniques; Embryology; Embryonic Induction; England; History, 20th Century; History, 21st Century; Mesoderm; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Organizers, Embryonic
PubMed: 29616723
DOI: 10.1387/ijdb.180028rb -
International Journal of Molecular... Aug 2022Vitelline membrane proteins (VMPs) are the main proteins that form the inner shell (vitelline membrane layer) of insect eggs and are an integral part of egg formation...
Vitelline membrane proteins (VMPs) are the main proteins that form the inner shell (vitelline membrane layer) of insect eggs and are an integral part of egg formation and embryo development. Here, we characterized the molecular structure and expression patterns of the gene and analyzed its reproductive functions in diamondback moth, (L.), a worldwide migratory pest of cruciferous plants. The gene was shown to be a single exon gene that contained an open reading frame of 852 base pairs (bp) encoding 283 amino acids. Both qPCR and western blot analyses showed that VMP26 was specifically expressed in female adults and was significantly highly expressed in the ovary. Further anatomical analysis indicated that the expression level of in the ovarian tube with an incomplete yolk was significantly higher than that in the ovarian tube with a complete yolk. CRISPR/Cas9-induced knockout successfully created two homozygous strains with 8- and 46-bp frameshift mutations. The expression deficiency of the VMP26 protein was detected in the mutant strains using immunofluorescence and western blot. No significant difference was found in the number of eggs laid within three days between wild and mutant individuals, but there was a lower egg hatchability. The loss of the gene changed the mean egg size, damaged the structure of the vitelline membrane, and increased the proportion of abnormal eggs due to water loss, resulting in egg collapse. This first analysis of the roles of the gene in the oocyte formation and embryonic development of , using CRISPR/Cas9 technology, provides a basis for screening new genetic control targets of .
Topics: Animals; CRISPR-Cas Systems; Egg Proteins; Female; Moths; Mutagenesis; Vitelline Membrane
PubMed: 36076934
DOI: 10.3390/ijms23179538 -
Poultry Science Sep 2017Vitelline membrane (VM) is a multilayered structure that surrounds the egg yolk serving to separate the yolk and the white. Due to its poor solubility in aqueous-based...
Vitelline membrane (VM) is a multilayered structure that surrounds the egg yolk serving to separate the yolk and the white. Due to its poor solubility in aqueous-based media, VM proteins and their biological properties have not been fully defined. In the current study, VM was hydrolyzed using different enzymes under the optimum hydrolysis conditions. Antioxidant and anti-inflammatory properties were evaluated in chemical and cellular models. Flavourzyme- and trypsin-treated samples showed the highest radical scavenging and ferric ion reducing effect (31% and 20 μM of Trolox equivalents/mg, respectively). In cellular studies, all VM hydrolysates were cyto-compatible and inhibited nitric oxide production by RAW264.7 macrophage cells significantly. Lipopolysaccharide-stimulated up-regulation of pro-inflammatory cytokines in RAW264.7 cells was suppressed by flavourzyme-treated VM. These results revealed that enzymatic hydrolysis of VM is a promising approach to produce peptides with several bioactivities (free radical scavenging, metal chelation, and anti-inflammatory) as valuable ingredients for cosmeceuticals and nutraceuticals.
Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Chickens; Egg Proteins; Hydrolysis; Models, Chemical; Protein Hydrolysates; Vitelline Membrane
PubMed: 28854750
DOI: 10.3382/ps/pex125 -
Scientific Reports Nov 2020In this study, we aimed to perform structural and proteomic analysis of the vitelline membrane (VM) of two species birds belonging to the family Turdidae: blackbird...
In this study, we aimed to perform structural and proteomic analysis of the vitelline membrane (VM) of two species birds belonging to the family Turdidae: blackbird (Turdus merula) and song thrush (Turdus philomelos). We performed structural analyses using scanning electron microscopy. The VM proteins were identified and compared to the best-known chicken VM proteins. According to our results, VM of both species has a typical three-layered structure: the outer layer, inner layer, and the continuous membrane between them. An unusual observation was the finding of "convexity" formed by the inner layer in blackbird. The role of these convex structures is not known, but they can be typical for the species and can be used in their identification. In addition, we identified two proteins in the VM of both species of birds, of which U3KEZ1 FICAL was not previously identified in any other bird species, and the U3JXV8 FICAL protein was confirmed only once in cockatiel parrot VM. The function of these proteins is not exactly known, but their structure shows similarities to the SERPIN proteins that are involved in microbiological defense, i.e., they are immune proteins. This study contributes to the current knowledge about the structure and composition of proteins of VM, especially because similar analyses have never been performed for Turdidae family. Knowledge of the structure and specific proteins of blackbird and song thrush VM can be beneficial in research on ecology and bird biology and also helpful in developing noninvasive and nongenetic identification methods.
Topics: Animals; Chickens; Egg Proteins; Egg Yolk; Female; Immune System; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Proteome; Songbirds; Species Specificity; Vitelline Membrane
PubMed: 33168893
DOI: 10.1038/s41598-020-76559-4 -
Seminars in Cell & Developmental Biology Feb 2017Twenty-seven serpins belonging to clade A, B, C, D, E, F, G, H and I serpins are currently referenced in chicken genome databases. Phylogenetic analysis of chicken... (Review)
Review
Twenty-seven serpins belonging to clade A, B, C, D, E, F, G, H and I serpins are currently referenced in chicken genome databases. Phylogenetic analysis of chicken serpins revealed that ovalbumin (Serpinb14) and its paralogs ovalbumin-related protein Y (Serpinb14b) and ovalbumin-related protein X (Serpinb14c) are found in bird species. These clade B serpins are specifically expressed in reproductive tissues and exported in the egg where they constitute major protein components. These data suggest that these three paralogs have probably appeared in birds to face new environments and ensure the extra-uterine development of an embryo in a shell egg. Twelve other serpins have been identified in the newly produced egg, some of them having a specific distribution in the respective egg structures (eggshell, egg white, vitelline membrane and egg yolk). The physiological role of these egg serpins remain largely unexplored, but there is increasing evidence in literature or by homologies with their mammalian counterparts, that some of them participate in cell proliferation, tissue remodeling and/or angiogenesis associated with folliculogenesis and development of extraembryonic structures, eggshell biomineralization, egg defense and nutrition of the embryo. A better knowledge of the phylogenetic evolution of these 15 serpins in other oviparous species, on their egg distribution, on their regulation during embryonic development (activation/degradation/transfer) and on their functional specificity, is needed to better appreciate their role and their bird-specificity. These review shed light on the multiple possibilities that offer the avian egg model to study the role of serpins in reproduction and developmental biology.
Topics: Animals; Chickens; Evolution, Molecular; Models, Molecular; Ovum; Phylogeny; Serpins
PubMed: 27565683
DOI: 10.1016/j.semcdb.2016.08.019 -
Wiley Interdisciplinary Reviews.... 2014The pathway that generates the dorsal-ventral (DV) axis of the Drosophila embryo has been the subject of intense investigation over the previous three decades. The... (Review)
Review
UNLABELLED
The pathway that generates the dorsal-ventral (DV) axis of the Drosophila embryo has been the subject of intense investigation over the previous three decades. The initial asymmetric signal originates during oogenesis by the movement of the oocyte nucleus to an anterior corner of the oocyte, which establishes DV polarity within the follicle through signaling between Gurken, the Drosophila Transforming Growth Factor (TGF)-α homologue secreted from the oocyte, and the Drosophila Epidermal Growth Factor Receptor (EGFR) that is expressed by the follicular epithelium cells that envelop the oocyte. Follicle cells that are not exposed to Gurken follow a ventral fate and express Pipe, a sulfotransferase that enzymatically modifies components of the inner vitelline membrane layer of the eggshell, thereby transferring DV spatial information from the follicle to the egg. These ventrally sulfated eggshell proteins comprise a localized cue that directs the ventrally restricted formation of the active Spätzle ligand within the perivitelline space between the eggshell and the embryonic membrane. Spätzle activates Toll, a transmembrane receptor in the embryonic membrane. Transmission of the Toll signal into the embryo leads to the formation of a ventral-to-dorsal gradient of the transcription factor Dorsal within the nuclei of the syncytial blastoderm stage embryo. Dorsal controls the spatially specific expression of a large constellation of zygotic target genes, the Dorsal gene regulatory network, along the embryonic DV circumference. This article reviews classic studies and integrates them with the details of more recent work that has advanced our understanding of the complex pathway that establishes Drosophila embryo DV polarity. For further resources related to this article, please visit the WIREs website.
CONFLICT OF INTEREST
The authors have declared no conflicts of interest for this article.
Topics: Animals; Body Patterning; Drosophila; Epistasis, Genetic; Gene Expression Regulation, Developmental; Gene Regulatory Networks
PubMed: 25124754
DOI: 10.1002/wdev.138 -
Frontiers in Cell and Developmental... 2021Fertilization is one of the most important events in living organisms to generate a new life with a mixed genetic background. To achieve successful fertilization, sperm... (Review)
Review
Fertilization is one of the most important events in living organisms to generate a new life with a mixed genetic background. To achieve successful fertilization, sperm and eggs must undergo complex processes in a sequential order. Fertilization of marine invertebrate type has been studied for more than a hundred years. Ascidian sperm are attracted by chemoattractants from eggs and bind to the vitelline coat. Subsequently, sperm penetrate through the vitelline coat proteolytically and finally fuse with the egg plasma membrane. Here, we summarize the fertilization mechanisms of ascidians, particularly from sperm-egg interactions to sperm penetration of the egg coat. Since ascidians are hermaphrodites, inbreeding depression is a serious problem. To avoid self-fertilization, ascidians possess a self-incompatibility system. In this review, we also describe the molecular mechanisms of the self-incompatibility system in type A governed by three allelic gene pairs of and .
PubMed: 35186958
DOI: 10.3389/fcell.2021.827214 -
BioRxiv : the Preprint Server For... May 2023The eggshell of the fruit fly is a useful model for understanding the synthesis of a complex extracellular matrix. The eggshell is synthesized during mid-to-late...
The eggshell of the fruit fly is a useful model for understanding the synthesis of a complex extracellular matrix. The eggshell is synthesized during mid-to-late oogenesis by the somatic follicle cells that surround the developing oocyte. We previously reported that female flies mutant for the gene ( ) are sterile, but the underlying cause of the sterility remained unknown. In this study, we examined the role of in eggshell synthesis. We show that eggs laid by mutant females are fertilized but arrest early in embryogenesis, and that the innermost layer of the eggshell, the vitelline membrane, is abnormally permeable to dye in these eggs. In addition, the major vitelline membrane proteins fail to become crosslinked by nonreducible bonds, a process that normally occurs during egg activation following ovulation, as evidenced by their solubility and detection by Western blot in laid eggs. In contrast, the Cp36 protein, which is found in the outer chorion layers of the eggshell, becomes crosslinked normally. To link the expression pattern with these phenotypes, we show that is expressed in the ovarian follicle cells beginning in mid-oogenesis, and, importantly, that all mutant eggshell phenotypes could be recapitulated by selective knockdown of expression in the follicle cells. To determine whether expression was required for the crosslinking itself, we performed in vitro activation and crosslinking experiments. The vitelline membranes of control egg chambers could become crosslinked either by incubation in hyperosmotic medium, which activates the egg chambers, or by exogenous peroxidase and hydrogen peroxide. In contrast, neither treatment resulted in the crosslinking of the vitelline membrane in mutant egg chambers. These results indicate that expression in the follicle cells is necessary for vitelline membrane proteins to serve as substrates for peroxidase-mediated cross-linking at the end of oogenesis.
PubMed: 37163052
DOI: 10.1101/2023.04.25.538335