Inter-specific Transfers of Eggs Between Rat and Mouse

Development ◽  
1962 ◽  
Vol 10 (4) ◽  
pp. 476-495
Author(s):  
Andrzej K. Tarkowski

Inter-Specific transplantations of mammalian eggs offer one possible way of studying the significance of intrinsic and external factors in embryonic development and their mutual interactions. The variety of problems which can be attacked by this method is dependent, of course, on the length of time during which development can proceed with a given combination of donor and recipient. The development of an egg in a specifically foreign animal can be adversely affected from the very beginning, though this is more likely to occur from the time of implantation onwards when all morphological, physiological,, and immunological differences between the embryo and the mother come to action. The available information, though very scanty, supports the view that during early development up to the formation of the blastocyst, the egg is highly tolerant of a foreign environment.

2001 ◽  
Vol 7 (S2) ◽  
pp. 1012-1013
Author(s):  
Uyen Tram ◽  
William Sullivan

Embryonic development is a dynamic event and is best studied in live animals in real time. Much of our knowledge of the early events of embryogenesis, however, comes from immunofluourescent analysis of fixed embryos. While these studies provide an enormous amount of information about the organization of different structures during development, they can give only a static glimpse of a very dynamic event. More recently real-time fluorescent studies of living embryos have become much more routine and have given new insights to how different structures and organelles (chromosomes, centrosomes, cytoskeleton, etc.) are coordinately regulated. This is in large part due to the development of commercially available fluorescent probes, GFP technology, and newly developed sensitive fluorescent microscopes. For example, live confocal fluorescent analysis proved essential in determining the primary defect in mutations that disrupt early nuclear divisions in Drosophila melanogaster. For organisms in which GPF transgenics is not available, fluorescent probes that label DNA, microtubules, and actin are available for microinjection.


Development ◽  
1990 ◽  
Vol 108 (1) ◽  
pp. 1-17 ◽  
Author(s):  
P.M. Wassarman

Complementary molecules on the surface of eggs and sperm are responsible for species-specific interactions between gametes during fertilization in both plants and animals. In this essay, several aspects of current research on the mouse egg receptor for sperm, a zona pellucida glycoprotein called ZP3, are addressed. These include the structure, synthesis, and functions of the sperm receptor during oogenesis and fertilization in mice. Several conclusions are drawn from available information. These include (I) ZP3 is a member of a unique class of glycoproteins found exclusively in the extracellular coat (zona pellucida) of mammalian eggs. (II) ZP3 gene expression is an example of oocyte-specific and, therefore, sex-specific gene expression during mammalian development. (III) ZP3 is a structural glycoprotein involved in assembly of the egg extracellular coat during mammalian oogenesis. (IV) ZP3 is a sperm receptor involved in carbohydrate-mediated gamete recognition and adhesion during mammalian fertilization. (V) ZP3 is an inducer of sperm exocytosis (acrosome reaction) during mammalian fertilization. (VI) ZP3 participates in the secondary block to polyspermy following fertilization in mammals. (VII) The extracellular coat of other mammalian eggs contains a glycoprotein that is functionally analogous to mouse ZP3. The unique nature, highly restricted expression, and multiple roles of ZP3 during mammalian development make this glycoprotein a particularly attractive subject for investigation at both the cellular and molecular levels.


2018 ◽  
Author(s):  
Ryohei Nakamura ◽  
Yuichi Motai ◽  
Masahiko Kumagai ◽  
Haruyo Nishiyama ◽  
Neva C. Durand ◽  
...  

Abstract:Genome architecture plays a critical role in gene regulation, but how the structures seen in mature cells emerge during embryonic development remains poorly understood. Here, we study early development in medaka (the Japanese killifish, Oryzias latipes) at 12 time points before, during, and after gastrulation which is the most dramatic event in early embryogenesis, and characterize transcription, protein binding, and genome architecture. We find that gastrulation is most associated with drastic changes in genome architecture, including the formation of the first loops between sites bound by the insulator protein CTCF and great increase in the size of contact domains. However, the position of CTCF is fixed throughout medaka embryogenesis. Interestingly, genome-wide transcription precedes the emergence of mature domains and CTCF-CTCF loops.


1935 ◽  
Vol s2-78 (309) ◽  
pp. 71-90
Author(s):  
HELEN MELLANBY

1. Eggs of Rhodnius prolixus were incubated at constant temperature and humidity (21° C. and 90 per cent, relative humidity). Eighty-five per cent, was the lowest record of the controls hatched successfully under these conditions. 2. The processes of maturation and fertilization were not studied. 3. Cleavage begins 12-13 hours after incubation. At 25 hours there are 32 nuclei. Yolk-cells are derived from cleavage nuclei, and they multiply by mitosis up to 50 hours. Blastoderm formation is complete after 55-60 hours of incubation. 4. The ventral embryonic rudiment is similar to that of many other insects. As soon as it is formed, germ-cells are budded off at the posterior pole of the egg. 5. The first stage in blastokinesis is fully described. 6. The formation of the mesoderm is by invagination and overgrowth. 7. The endoderm arises from two proliferating areas situated anteriorly and posteriorly. 8. Numerous cells are given off into the yolk during the early development of the embryo. There they disintegrate.


2013 ◽  
Vol 200 (5) ◽  
pp. 667-679 ◽  
Author(s):  
Kathryn Ellis ◽  
Jennifer Bagwell ◽  
Michel Bagnat

The notochord plays critical structural and signaling roles during vertebrate development. At the center of the vertebrate notochord is a large fluid-filled organelle, the notochord vacuole. Although these highly conserved intracellular structures have been described for decades, little is known about the molecular mechanisms involved in their biogenesis and maintenance. Here we show that zebrafish notochord vacuoles are specialized lysosome-related organelles whose formation and maintenance requires late endosomal trafficking regulated by the vacuole-specific Rab32a and H+-ATPase–dependent acidification. We establish that notochord vacuoles are required for body axis elongation during embryonic development and identify a novel role in spine morphogenesis. Thus, the vertebrate notochord plays important structural roles beyond early development.


2021 ◽  
Vol 92 ◽  
pp. 08007
Author(s):  
Victor Dengov ◽  
Irina Tulyakova ◽  
Elena Gregova

Research background: The products of the arms and military equipment market create the material basis for the country’s military security. The most important segment of this market is the market of naval equipment. The acquired competencies have naturally led Russia to the role of the most important exporter in this market. The authors have repeatedly addressed the topic of Russian shipbuilding and the role of Russia in the world market of naval equipment and military ships. Purpose of the article: The main goal of the research is to analyze the current state of the market of naval equipment, the positions of its main participants and, especially, Russia. To determine the future prospects of Russia’s presence in this market, it was necessary to identify the main problems of Russian shipbuilding and consider the impact of external factors on the state of the industry. Methods: Generalizations of the research are based on processing and systematization of data obtained from available information sources. Analyzing the statistics, the authors were able to deduce the trends of the current moment and determine the prospects. Findings & Value added: The analysis of key market indicators, as well as the problems of Russian shipbuilding, allowed the authors to build possible scenarios for its future development, from optimistic under favorable external factors to pessimistic, in which the loss of not only military security, but also the position of the largest exporter in the world market of naval equipment and military ships is inevitable.


2020 ◽  
Vol 2 (1) ◽  
pp. p1
Author(s):  
Md. Borhan Uddin Ahmed ◽  
Jobayda Sifat ◽  
Md. Fazla Rabbi ◽  
Md. Ashraful Islam ◽  
H.M. Al Kabid Rafin ◽  
...  

The early developmental pattern of inland fishes of Bangladesh are not well studied though it has a great importance in fisheries and aquaculture sector. The embryonic study provides interesting information on further growth and health of the fish and considered as an essential component for optimization of fish seed production by natural and induced breeding. Therefore, the current review work has been undertaken to provide a detail information on embryonic development of important inland fishes of Bangladesh. Information was collected from published scientific papers, un-published Masters and PhD dissertations from universities, popular articles and other published and grey literature. Diameters of unfertilized egg of the reviewed fish species were found to be 0.5 to 1.3 mm and fertilized egg were 0.49 to 1.6 mm. Shapes of the egg were also variable from species to species. There is little information available on egg activation and egg micropyle of fish species of Bangladesh. The fertilization rate of different fishes ranged from 40.1% to 93.9%. There are different stages of early development in different species and time needs to complete the stages also vary. The timing of post hatching development by metamorphosis was found to vary based on the fish species from several days to weeks. Different factors like temperature, photoperiod, DO, seasonality and presence of chemicals in water were found to affect the early development of fish. The review included eighteen inland fishes and unearthed useful insights of their embryonic development and influence of different factors. As we expect, the outcome of the study would provide a baseline and would be very useful in conducting further research on the embryology of indigenous fishes of Bangladesh. 


2021 ◽  
Author(s):  
Eraqi R. Khannoon ◽  
Christian Alvarado ◽  
Maria Elena Elena de Bellard

Abstract Background: Trunk neural crest cells (TNCC) are representing a model for epithelial to mesenchymal transition, this correlates the importance of studying the migration of these cells to cancer metastasis. Reptiles are unique group of animals being very morphologically diverse and their close position to synapsid leading to mammals. Recently, more publications focused on the migratory behavior of trunk NCC during embryonic development of squamates. Only one colubrid snake has been studied so far regarding the NCC migration. Results: Here we follow the migratory behavior of TNCC with HNK1 in the elapid snake Naja h. haje from early stage to 14 days postoviposition. Comparing the colubrid snake with the Egyptian cobra showed that both snakes overall follow the same TNCC migratory pathways of both birds and mammals by following the rostral and avoiding the caudal portions of the somites. Conclusions: First, TNCC intra-somitic migration as observed in turtles supports a contributing role for TNCC to scale precursors. Second, our observation of significant numbers of migrating TNCC in the intersomitic pathway suggest interesting evolutionary differences. Together, our present results of the Egyptian cobra in combination with those on a colubrid and turtle supports intersomitic TNCC as a unique reptile phenomena.


2021 ◽  
Author(s):  
◽  
Jeannine Fischer

<p>Salinity, temperature and ultraviolet-B (UV-B) radiation are common environmental stressors in coastal habitats. These stressors are likely to increase in intensity due to the effects of climate change and can have important impacts on population and community dynamics for early development in gastropods that deposit egg masses on rocky shores. The aim of this study was to identify the effects of single and multiple stressors on the development of intertidal and shallow subtidal gastropods with encapsulated embryos. In manipulative experiments I exposed egg masses of the gastropod species Siphonaria australis, Ercolania felina, Pleurobranchaea maculata, Aplysia juliana and Doris wellingtonensis to realistic levels of either salinity, temperature or UV-B radiation, or to a combination of stressors, for different lengths of time. Embryos were then subjected to the most stressful levels of each stressor at either early or late stages of development and at different days of embryonic development. Further, egg masses were exposed to sublethal salinity, temperature and UV-B radiation stress simultaneously, simulating tide pool conditions on a warm sunny summer day. Larvae hatching from stressed and unstressed egg masses were subsequently periodically subjected to increased temperature and UV-B radiation and examined over 10 days to detect possible carry-over effects of exposure to stress in the egg mass. The results revealed that for individual stressors, low salinity (20‰), high temperature (25°C) and high UV-B (1.7 W m ⁻ ² s ⁻ ¹, i.e. a level similar to a sunny NZ summer day) all caused the highest embryonic mortality. The response to stressors was species-specific but overall the intertidal species had lower embryonic mortality than the subtidal species. Generally, chronic exposure had higher impacts on the development of embryos than periodic exposure and early embryonic development stages were most vulnerable to stress. UV-B radiation had particularly damaging effects on embryonic and larval stages for the intertidal pulmonate limpet Siphonaria australis. Further, multiple stressors had synergistic effects and caused high embryonic mortality in the egg mass as well as impacting on the vulnerability of larvae to stressors. This study revealed that stress experienced during embryonic stages can result in sub-lethal damage that increases vulnerability to temperature and decreases vulnerability to UV-B radiation experienced in the larval stage. In total, my results suggest that (1) the effects of different environmental stressors on early development of intertidal and subtidal gastropods are complex and depend on the intensity, duration and time of stress, and are generally species-specific; (2) multiple stressors can act synergistically to affect early development and (3) sublethal exposure to stress in the egg mass can have negative carry-over effects on later larval stages.</p>


2021 ◽  
Vol 29 (1) ◽  
pp. 9-19
Author(s):  
Oksana V. Shurygina ◽  
Ol'ga Yu. Vasilenko ◽  
Sergey N. Yukhimets ◽  
Nikita A. Shipulin

Despite advances in assisted reproductive technologies, the high failure rate of existing stimulation protocols remains a key industry challenge. One of the leading reasons for this is the limited ability to assess the biological potential of the embryo and its chances of implantation. Over the past ten years, the focus of attention in reproductive technologies has significantly shifted from the patient to the embryo, since the need to improve their effectiveness stimulates the need to understand the deep processes of early development of the embryo. In order to increase the effectiveness of in vitro fertilization procedures in clinical embryology, high-tech methods of culturing and evaluating embryos are being introduced and improved. The purpose of the review is to demonstrate the history, possibilities and prospects in the study of early human embryonic development of time-lapse imaging technology. The active study and use of the capabilities of the time-lapse slow-motion technology allowed not only to expand the understanding of the processes of early development of the embryo, but also at the current moment allows us to assess its potential from the point of view of both biological and clinical perspectives. The main advantages of this method are the possibility of morphological assessment during the continuous cultivation of embryos in closed-type incubators without their extraction, as well as the determination of the exact time intervals of key events of the stages of embryo development with special attention to those moments that are not available for observation and fixation under conditions of traditional cultivation. clinical practice. The main point of growth for the development of time-lapse imaging technology was the creation and validation of the so-called morphokinetic criteria and algorithms for assessing the quality of developing embryos. The key perspective of the method is its use in combination with elements of artificial intelligence in order to predict the most potential embryo for transfer into the uterine cavity. Modern directions of research using the method of time-lapse shooting are the continuation of the development of morphokinetic algorithms and their effective criteria, the introduction of the technology of self-learning computer programs and the adaptation of these tools in clinical practice, the search and assessment of possible factors influencing the morphokinetics of embryos, quality control of the work of embryological laboratories. The future development of such technologies is presented in combination not only with the capabilities of artificial intelligence, but also in combination with the use of non-invasive genetic screening, the assessment of metabolomics and proteomics of developing embryos.


Sign in / Sign up

Export Citation Format

Share Document