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21.
The integral membrane protein known as prominin was first identified on the apical surface of mouse neural epithelial cells as well as on the surface of human haematopoietic progenitor cells. This report describes a prominin-like sequence and expression analysis of the prominin in the goldfish. The predicted amino acid sequence for goldfish prominin shares all of the hallmark structural characteristics of the prominin family, however the relatedness assessed using the percent amino acid identity indicated that goldfish prominin cannot be placed into the current mammalian dichotomy of type 1 or 2. The real time PCR analyses indicated that prominin was broadly expressed in different tissues with particularly high levels observed in the kidney and gill of the goldfish. Goldfish prominin was also found to be differentially expressed in subpopulations of in vitro-derived goldfish macrophages, with the highest expression observed in progenitor cells. 相似文献
22.
Nuclear-cytoplasmic interactions affect in utero developmental capacity, phenotype, and cellular metabolism of bovine nuclear transfer fetuses 总被引:3,自引:0,他引:3
Hiendleder S Prelle K Brüggerhoff K Reichenbach HD Wenigerkind H Bebbere D Stojkovic M Müller S Brem G Zakhartchenko V Wolf E 《Biology of reproduction》2004,70(4):1196-1205
We generated a clone of bovine somatic cell nuclear transfer embryos using oocyte pools from defined maternal sources to study nuclear-cytoplasmic interactions. Nucleocytoplasmic hybrids were reconstructed with Bos taurus (Brown Swiss) granulosa cells and oocytes that contained B. taurus A (Simmental), B. taurus B (Simmental), or Bos indicus (Dwarf Zebu) cytoplasm. Another set of embryos was reconstructed with randomly selected Brown Swiss (B. taurus R) oocytes. Embryo transfer resulted in nine (12.5%), nine (13.8%), three (50%), and 11 (16.7%) Day 80 fetuses, of which eight (11.1%), three (4.6%), three (50%), and 10 (15.2%) were viable, respectively. The proportion of viable fetuses was affected by cytoplasm (likelihood ratio test, P < 0.02) and was higher for embryos with B. indicus cytoplasm than for the B. taurus A (P < 0.05) and B (P < 0.01) groups. Furthermore, the proportion of surviving Day 80 fetuses was reduced for B. taurus B as compared with B. taurus A and B. taurus R cytoplasm (P < 0.05 and P < 0.02). Body weight of nucleocytoplasmic hybrid fetuses was not significantly different from Brown Swiss control fetuses produced by artificial insemination (AI), but fetuses reconstructed with random cytoplasts of the same breed as the nuclear donor exhibited overgrowth (P < 0.01) and a higher coefficient of variation in weight. Furthermore, body weight, crown rump length, thorax circumference (P < 0.05), and femur length (P < 0.01) of fetuses with B. taurus A cytoplasm differed from fetuses with B. taurus R cytoplasms. Fetal skin, heart, and liver cells with B. indicus cytoplasm showed a greater increase in number per time period (P < 0.001) and oxygen consumption rate per cell (skin and liver, P < 0.001; heart, P < 0.08) in comparison with their counterparts with B. taurus A cytoplasm. These data point to complex oocyte cytoplasm-dependent epigenetic modifications and/or nuclear DNA-mitochondrial DNA interactions with relevance to nuclear transfer and other reproductive technologies such as ooplasmic transfer in human assisted reproduction. 相似文献
23.
Moritz KM Jefferies A Wintour EM Dodic M 《American journal of physiology. Regulatory, integrative and comparative physiology》2005,288(1):R62-R66
Maternal infusion of dexamethasone for 48 h early in gestation results in upregulation of mRNA for mineralocorticoid and glucocorticoid (MR and GR) receptors and angiotensin II receptors in ovine fetal kidneys late in gestation. This study sought to determine whether dexamethasone exposure results in changes in renal function and blood pressure responsiveness to infused cortisol or aldosterone in the late-gestation fetus. Merino ewes carrying single fetuses were infused with isotonic saline (Sal; n = 9) or dexamethasone (Dex, 0.48 mg/h; n = 10) for 48 h between days 26 and 28 of gestation (term = 150 days). At 115-122 days, renal function and blood pressure were measured in fetuses during a 4-h infusion of saline, cortisol (100 microg/h), or aldosterone (5 microg/h). Infusions were given in random order at least 2 days apart. Basal blood pressure and renal function were similar in Sal and Dex groups and did not change over the course of saline infusion. Cortisol infusion caused similar increases in blood pressure, urine flow, and glomerular filtration rate (GFR) in the groups. Aldosterone infusion caused a significantly different GFR response between the groups [P(treatment x time) < 0.05], but increase in K excretion and decrease in Na-to-K ratio were similar in the groups. The similar results obtained with cortisol and aldosterone infusion suggest no increased renal functional maturity to those hormones after early prenatal dexamethasone exposure. This suggests that changes in mRNA for MR and GR in kidneys of dexamethasone-exposed fetuses do not result in functional differences and highlights the renin-angiotensin system, as reported previously, as more important in this model. 相似文献
24.
Concealed development of many animal embryos prevents examination of development and limits the application of embryo manipulation
techniques aimed at understanding developmental processes. In embryos developing in utero, such as in mammals, it is necessary
to dissect embryos from the mother and, upon manipulative intervention, to implant them back into the recipient. Parasitic
wasps present a promising system for understanding the evolution of early developmental processes. In basal ectoparasitic
species that lay eggs on the surface of the host, it is possible to adapt embryo manipulation techniques developed in Drosophila. However, their derived endoparasitic relatives, which exhibit various modifications of developmental programs, undergo concealed
development within the host body. For example, the parasitic polyembryonic wasp Copidosoma floridanum oviposits an egg into the egg of the host moth Trichoplusia ni. The host larva emerges and the parasite undergoes development within the host body, preventing embryo manipulation as a
means of examining developmental regulation. Here we present a protocol for embryo transfer that allows the transplantation
of C. floridanum egg into the host egg. This approach opens a new avenue in the application of various embryo manipulation techniques aimed
at understanding the evolution of embryogenesis in endoparasitic Hymenoptera. In addition, this approach has potential for
the development of other tools in C. floridanum, such as transgenesis and reverse genetics, which can also be extended to other endoparasitic species. 相似文献
25.
Golnaz Salehipourshirazi Kristie Bruinsma Huzefa Ratlamwala Sameer Dixit Vicent Arbona Emilie Widemann Maja Milojevic Pengyu Jin Nicolas Bensoussan Aurelio Gmez-Cadenas Vladimir Zhurov Miodrag Grbic Vojislava Grbic 《Plant physiology》2021,187(4):2608
Genetic adaptation, occurring over a long evolutionary time, enables host-specialized herbivores to develop novel resistance traits and to efficiently counteract the defenses of a narrow range of host plants. In contrast, physiological acclimation, leading to the suppression and/or detoxification of host defenses, is hypothesized to enable broad generalists to shift between plant hosts. However, the host adaptation mechanisms used by generalists composed of host-adapted populations are not known. Two-spotted spider mite (TSSM; Tetranychus urticae) is an extreme generalist herbivore whose individual populations perform well only on a subset of potential hosts. We combined experimental evolution, Arabidopsis thaliana genetics, mite reverse genetics, and pharmacological approaches to examine mite host adaptation upon the shift of a bean (Phaseolus vulgaris)-adapted population to Arabidopsis. We showed that cytochrome P450 monooxygenases are required for mite adaptation to Arabidopsis. We identified activities of two tiers of P450s: general xenobiotic-responsive P450s that have a limited contribution to mite adaptation to Arabidopsis and adaptation-associated P450s that efficiently counteract Arabidopsis defenses. In approximately 25 generations of mite selection on Arabidopsis plants, mites evolved highly efficient detoxification-based adaptation, characteristic of specialist herbivores. This demonstrates that specialization to plant resistance traits can occur within the ecological timescale, enabling the TSSM to shift to novel plant hosts.Mites can evolve highly efficient detoxification-based adaptation in approximately 25 generations on an initially unfavorable plant host, revealing that specialization can occur within the ecological timescale. 相似文献
26.
Miodrag Petrović Ilijana Grigorov Tanja Milosavljević Desanka Bogojević Snežana Ŝekularac Ljiljana Ševaljević 《Molecular biology reports》1996,23(2):79-85
A 29 kD soluble rat liver nucleoprotein (p29) has increased binding affinity for the hormone responsive element (RE) of the rat haptoglobin (Hp) gene during the acute-phase reaction. In this work the possibility of its structural and functional homology to the high mobility group 1 (HMG1) nonhistone protein constituent of chromatin was examined. The results of two-dimensional gel electrophoresis, Southwestern and Western immunoblot analyses, showed that p29 and HMG1 are homologous protein species. On the basis of in vitro and in vivo phosphorylation/dephosphorylation experiments, we discuss the modulatory role of phosphate groups in view of the structure and function of p29. 相似文献
27.
28.
Dong Li Stephen A. Craik Daniel W. Smith Miodrag Belosevic 《Applied microbiology》2007,73(7):2218-2223
The effects of 254-nm UV irradiation on two human isolates (WB and H3) of Giardia lamblia cysts were assessed using a collimated beam protocol and a Mongolian gerbil model. The levels of infection of cysts in the gerbils were assessed based on the presence of cysts in feces and the presence and activity of trophozoites in the small intestine of inoculated gerbils. The results suggest that there were differences in the infectivities of the WB and H3 isolates, as well as in susceptibilities of the parasites to UV light. Without UV exposure, gerbils were more readily infected by isolate H3 cysts. After UV exposure of the cysts, however, the gerbils were more susceptible to isolate WB cysts. 相似文献
29.
Sergej Tomi? Jelena ?oki? Sa?a Vasiliji? Nina Ogrinc Rebeka Rudolf Primo? Pelicon Dragana Vu?evi? Petar Milosavljevi? Sr?a Jankovi? Ivan An?el Jelena Rajkovi? Marjan Slak Rupnik Bernd Friedrich Miodrag ?oli? 《PloS one》2014,9(5)
Gold nanoparticles (GNPs) are claimed as outstanding biomedical tools for cancer diagnostics and photo-thermal therapy, but without enough evidence on their potentially adverse immunological effects. Using a model of human dendritic cells (DCs), we showed that 10 nm- and 50 nm-sized GNPs (GNP10 and GNP50, respectively) were internalized predominantly via dynamin-dependent mechanisms, and they both impaired LPS-induced maturation and allostimulatory capacity of DCs, although the effect of GNP10 was more prominent. However, GNP10 inhibited LPS-induced production of IL-12p70 by DCs, and potentiated their Th2 polarization capacity, while GNP50 promoted Th17 polarization. Such effects of GNP10 correlated with a stronger inhibition of LPS-induced changes in Ca2+ oscillations, their higher number per DC, and more frequent extra-endosomal localization, as judged by live-cell imaging, proton, and electron microscopy, respectively. Even when released from heat-killed necrotic HEp-2 cells, GNP10 inhibited the necrotic tumor cell-induced maturation and functions of DCs, potentiated their Th2/Th17 polarization capacity, and thus, impaired the DCs'' capacity to induce T cell-mediated anti-tumor cytotoxicity in vitro. Therefore, GNP10 could potentially induce more adverse DC-mediated immunological effects, compared to GNP50. 相似文献
30.