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PloS One 2015Melamine is an organic nitrogenous compound widely used as an industrial chemical, and it has been recently reported by us that melamine has a toxic effect on the female...
Melamine is an organic nitrogenous compound widely used as an industrial chemical, and it has been recently reported by us that melamine has a toxic effect on the female reproductive system in mice, and renders females subfertile; the molecular basis, however, has not been adequately assessed. In the present study, we explore the underlying mechanism regarding how melamine compromises fertility in the mouse. The data showed that melamine exposure significantly impaired the fertilization capability of the egg during in vitro fertilization. To further figure out the cause, we analyzed ovastacin localization and protein level, the sperm binding ability of zona pellucida, and ZP2 cleavage status in unfertilized eggs from melamine fed mice, and no obvious differences were found between control and treatment groups. However, the protein level of Juno on the egg plasma membrane in the high-dose feeding group indeed significantly decreased compared to the control group. Thus, these data suggest that melamine compromises female fertility via suppressing Juno protein level on the egg membrane.
Topics: Animals; Cell Membrane; Female; Fertility; Mice; Mice, Inbred ICR; Ovum; Receptors, Cell Surface; Sperm-Ovum Interactions; Triazines; Zona Pellucida
PubMed: 26633308
DOI: 10.1371/journal.pone.0144248 -
The Journal of Biophysical and... Dec 1961A study has been made of the content and composition of RNA in cytoplasm, nucleoplasm, and nucleoli from growing oocytes of the starfish Asterias rubens. The...
A study has been made of the content and composition of RNA in cytoplasm, nucleoplasm, and nucleoli from growing oocytes of the starfish Asterias rubens. The determinations were carried out, using ultramicrochemical methods, on units isolated by microdissection from fixed sections. Macrochemical and interferometric control experiments show that RNA can be quantitatively evaluated in this way. The results show that the growing oocyte represents a system in which the relations between the quantities of nucleolar, nucleoplasmic, and cytoplasmic RNA undergo great changes. These changes are continuous for nucleolar and cytoplasmic RNA so that their amounts may be predicted from the size of the cell. Nucleoplasmic RNA, on the other hand, shows great variations among different cells, independent of cell size. Purine-pyrimidine analyses show that each cell component contains an RNA which differs significantly from that of the other two. Cytoplasmic and nucleolar RNA are closely related, the only difference being a slightly higher guanine/uracil quotient for the nucleolar RNA. They are both of the usual tissue RNA type, i.e., they show a preponderance of guanine and cytosine over adenine and uracil. Nucleoplasmic RNA deviates grossly from the RNA of the other two components. Here the concentrations of adenine and uracil are higher than those of guanine and cytosine, respectively. This RNA consequently shows some resemblance to the general type of animal DNA although the purine/pyrimidine ratio is far from unity. Our data favor a nucleolar origin for the stable part of the ribosomal RNA and a nucleoplasmic one for the unstable part (the messenger RNA).
Topics: Adenine; Animals; Cell Nucleolus; Cell Nucleus; Cytoplasm; Cytosine; DNA; Guanine; Oocytes; Ovum; RNA; RNA, Messenger; RNA, Ribosomal; Starfish; Uracil
PubMed: 13889253
DOI: 10.1083/jcb.11.3.549 -
Poultry Science Feb 2019In our experiment, we deal with the phenomenon of radiation hormesis and improvements based on this phenomenon to different growing characteristics of the fast-growing,...
In our experiment, we deal with the phenomenon of radiation hormesis and improvements based on this phenomenon to different growing characteristics of the fast-growing, very feed-efficient, and with a high-yielding carcass hybrid of the Peking duck (Cherry Valley SM3 medium). In the first phase of the project, we exposed hatching duck eggs to low and middle doses of gamma radiation 60Co (0.06-2.00 Gy) before placing them into a setter in the hatchery. We then followed the standards of artificial incubation. The treatment of our chosen doses of gamma radiation has no significant influence on the history and results of hatching (from 85.5% to 92.6%); it was influenced only by the basic management and husbandry of the parent stock. From our observations we confirm that the Peking duck, despite genetic progress, retained its vitality and robustness. Its embryos are not damaged even with a dose of 2 Gy, which is over the deterministic effect of ionizing radiation for vertebrates. At the end of the fatting period a significant drop in plasma phosphorus levels was measured in the ducks; however, it was dependent on the radiation dose to which the hatching eggs were exposed (r = -0.965). A positive effect of radiation hormesis may be expected in the case of 1 Gy dose where the highest values of mean corpuscular hemoglobin, mean corpuscular hemoglobin, combined hemoglobin, and drake weight were measured. Lower and higher doses of ionizing radiation used did not display these effects.
Topics: Animals; Cobalt Radioisotopes; Dose-Response Relationship, Radiation; Ducks; Gamma Rays; Hormesis; Ovum; Random Allocation; Reproduction
PubMed: 30169731
DOI: 10.3382/ps/pey391 -
Yonsei Medical Journal 1973
Topics: Animals; Blastocyst; Embryo Implantation; Embryo, Mammalian; Embryonic and Fetal Development; Female; Fertilization; Mice; Ovulation; Ovum; Temperature; Time Factors
PubMed: 4804134
DOI: 10.3349/ymj.1973.14.1.63 -
Molecular and Cellular Biology Nov 1993Exogenous DNA is efficiently recombined when injected into the nuclei of Xenopus laevis oocytes. This reaction proceeds by a homologous resection-annealing mechanism...
Exogenous DNA is efficiently recombined when injected into the nuclei of Xenopus laevis oocytes. This reaction proceeds by a homologous resection-annealing mechanism which depends on the activity of a 5'-->3' exonuclease. Two possible functions for this recombination activity have been proposed: it may be a remnant of an early process in oogenesis, such as meiotic recombination or amplification of genes coding for rRNA, or it may reflect materials stored for embryogenesis. To test these hypotheses, recombination capabilities were examined with oocytes at various developmental stages. Late-stage oocytes performed only homologous recombination, whereas the smallest oocytes ligated the restriction ends of the injected DNA but supported no homologous recombination. This transition from ligation to recombination activity was also seen in nuclear extracts from these same stages. Exonuclease activity was measured in the nuclear extracts and found to be low in early stages and then to increase in parallel with recombination capacity in later stages. The accumulation of exonuclease and recombination activities during oogenesis suggests that they are stored for embryogenesis and are not present for oocyte-specific functions. Eggs were also tested and found to catalyze homologous recombination, ligation, and illegitimate recombination. Retention of homologous recombination in eggs is consistent with an embryonic function for the resection-annealing mechanism. The observation of all three reactions in eggs suggests that multiple pathways are available for the repair of double-strand breaks during the extremely rapid cleavage stages after fertilization.
Topics: Animals; DNA; DNA, Ribosomal; Exodeoxyribonucleases; Female; Fertilization; In Vitro Techniques; Kinetics; Nuclear Proteins; Oocytes; Ovulation Induction; Ovum; Recombination, Genetic; Restriction Mapping; Xenopus laevis
PubMed: 8413282
DOI: 10.1128/mcb.13.11.6897-6906.1993 -
Molecules (Basel, Switzerland) Feb 2021In developing countries, crop deterioration is mainly caused by inappropriate storage conditions that promote insect infestation. Synthetic pesticides are associated...
In developing countries, crop deterioration is mainly caused by inappropriate storage conditions that promote insect infestation. Synthetic pesticides are associated with serious adverse effects on humans and the environment. Thus, finding alternative "green" insecticides is a very pressing need. (Aiton) Dryand (Apocynaceae) growing in Saudi Arabia was selected for this purpose. LC-MS/MS analysis was applied to investigate the metabolic composition of different extracts. Particularly, latex and leaves showed a high presence of cardenolides including calactin, uscharidin, 15β-hydroxy-calactin, 16β-hydroxy-calactin, and 12β-hydroxy-calactin. The ovicidal activity of the extracts from different plant organs (flowers, leaves, branches, roots), and of the latex, against (Walker) (Lepidoptera, Pyralidae) was assessed. Extracts of roots displayed the most potent activity with 50% of eggs not hatching at 10.000 ppm (1%).
Topics: Animals; Calotropis; Flowers; Latex; Moths; Ovum; Phytochemicals; Plant Extracts; Plant Leaves; Plant Roots
PubMed: 33572107
DOI: 10.3390/molecules26040905 -
Scientific Reports Sep 2020Maternal effects via hormonal transfer from the mother to the offspring provide a tool to translate environmental cues to the offspring. Experimental manipulations of...
Maternal effects via hormonal transfer from the mother to the offspring provide a tool to translate environmental cues to the offspring. Experimental manipulations of maternally transferred hormones have yielded increasingly contradictory results, which may be explained by differential effects of hormones under different environmental contexts. Yet context-dependent effects have rarely been experimentally tested. We therefore studied whether maternally transferred thyroid hormones (THs) exert context-dependent effects on offspring survival and physiology by manipulating both egg TH levels and post-hatching nest temperature in wild pied flycatchers (Ficedula hypoleuca) using a full factorial design. We found no clear evidence for context-dependent effects of prenatal THs related to postnatal temperature on growth, survival and potential underlying physiological responses (plasma TH levels, oxidative stress and mitochondrial density). We conclude that future studies should test for other key environmental conditions, such as food availability, to understand potential context-dependent effects of maternally transmitted hormones on offspring, and their role in adapting to changing environments.
Topics: Animals; Animals, Newborn; Female; Growth and Development; Ovum; Pregnancy; Prenatal Exposure Delayed Effects; Songbirds; Thyroid Hormones
PubMed: 32884067
DOI: 10.1038/s41598-020-71511-y -
Proceedings of the National Academy of... Jan 2020Offspring ornamentation typically occurs in taxa with parental care, suggesting that selection arising from social interactions between parents and offspring may...
Offspring ornamentation typically occurs in taxa with parental care, suggesting that selection arising from social interactions between parents and offspring may underlie signal evolution. American coot babies are among the most ornamented offspring found in nature, sporting vividly orange-red natal plumage, a bright red beak, and other red parts around the face and pate. Previous plumage manipulation experiments showed that ornamented plumage is favored by strong parental choice for chicks with more extreme ornamentation but left unresolved the question as to why parents show the preference. Here we explore natural patterns of variation in coot chick plumage color, both within and between families, to understand the context of parental preference and to determine whose fitness interests are served by the ornamentation. Conspecific brood parasitism is common in coots and brood parasitic chicks could manipulate hosts by tapping into parental choice for ornamented chicks. However, counter to expectation, parasitic chicks were duller (less red) than nonparasitic chicks. This pattern is explained by color variation within families: Chick coloration increases with position in the egg-laying order, but parasitic eggs are usually the first eggs a female lays. Maternal effects influence chick coloration, but coot females do not use this mechanism to benefit the chicks they lay as parasites. However, within families, chick coloration predicts whether chicks become "favorites" when parents begin control over food distribution, implicating a role for the chick ornamentation in the parental life-history strategy, perhaps as a reliable signal of a chick's size or age.
Topics: Animals; Biological Evolution; Birds; Breeding; Color; Female; Male; Nesting Behavior; Ovum; Pedigree; Selection, Genetic
PubMed: 31888995
DOI: 10.1073/pnas.1913615117 -
Proceedings. Biological Sciences May 2010The differential allocation hypothesis assumes that animals should weigh costs and benefits of investing into reproduction with a current mate against the expected...
The differential allocation hypothesis assumes that animals should weigh costs and benefits of investing into reproduction with a current mate against the expected quality of future mates, and predicts that they should invest more into reproduction when pairing with a high-quality mate. In the broad-nosed pipefish (Syngnathus typhle), males care for the embryos in a brood pouch and females compete for access to male mating partners. Both sexes prefer mating with large partners. In the present study, we show that the same female provides both large and small mating partners with eggs of similar size, weight and lipid content when mated to two males in succession. Importantly, however, eggs provided to small males (less preferred) had higher egg protein content (11% more) than those provided to large males (preferred). Thus, contrary to the differential allocation hypothesis, eggs did not contain more resources when females mated with a larger male. Instead, the pattern observed in our results is consistent with a compensatory reproductive strategy.
Topics: Animals; Egg Proteins; Female; Fishes; Male; Mating Preference, Animal; Ovum; Reproduction; Sexual Behavior, Animal
PubMed: 20106851
DOI: 10.1098/rspb.2009.2290 -
The Journal of Veterinary Medical... Oct 2002Sperm ejaculated by 8 beagle dogs and the cumuli oophori collected from 3 estrous beagle bitches were co-incubated, and penetration of the sperm into cumuli was observed...
Sperm ejaculated by 8 beagle dogs and the cumuli oophori collected from 3 estrous beagle bitches were co-incubated, and penetration of the sperm into cumuli was observed to investigate the influence of cumuli on homologous sperm. The percentages of hyperactivated sperm and acrosome-reacted sperm were calculated after incubation with homogenized cumuli. The hyaluronic acid content of the incubated cumuli was measured, and hyperactivation and the acrosome reaction of the sperm were evaluated in medium containing hyaluronic acid. The mean percentage of hyperactivated sperm (33.0%) and number (3.0) of sperm that had penetrated a cumulus among sperm incubated for 7 hr were significantly higher than the values for sperm incubated for 0.5 hr (P<0.01). Almost all sperm that had penetrated the cumuli had intact acrosome, as though they were hyperactivated. The percentages of motile sperm (77.3%) and hyperactivated sperm (23.6%) after 2 hr incubation in the medium containing homogenized cumuli were significantly higher than in control medium (P<0.01), but there was no difference between cumulus and control media in the percentages of acrosome-reacted sperm. The hyaluronic acid content of a cumulus increased after 24 hr incubation. After 2 and 4 hr of incubation the percentages of hyperactivated sperm in the medium containing hyaluronic acid were significantly higher than in the control medium (P<0.01). These results suggest that canine hyperactivated sperm with intact acrosome can penetrate homologous cumuli and that the sperm are able to pass through the cumulus because the hyperactivated movement is maintained by hyaluronic acid secreted by the cumulus cells.
Topics: Animals; Dogs; Female; Hyaluronic Acid; Male; Ovum; Sperm Capacitation; Sperm Motility; Sperm-Ovum Interactions; Spermatozoa; Time Factors
PubMed: 12419861
DOI: 10.1292/jvms.64.867