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21.
Carrera I Sueiro C Molist P Holstein GR Martinelli GP Rodríguez-Moldes I Anadón R 《Cell and tissue research》2006,323(2):273-281
The present immunocytochemical study provides evidence of a previously unrecognized, rich, γ-aminobutyric acid (GABA)-ergic
innervation of the pineal organ in the dogfish (Scyliorhinus canicula). In this elasmobranch, the pineal primordium is initially detected at embryonic stage 24 and grows to form a long pineal
tube by stage 28. Glutamic acid decarboxylase (GAD)-immunoreactive (-ir) fibers were first observed at stage 26, and by stage
28, thin GAD-ir fibers were detectable at the base of the pineal neuroepithelium. In pre-hatchling embryos, most fibers gave
rise to GAD-ir boutons that were localized in the basal region of the neuroepithelium, although a smaller number of labeled
terminals ascended to the pineal lumen. A few pale GAD-ir perikarya were observed within the pineal organ of stage 29 embryos,
but GAD-ir perikarya were not observed at other developing stages or in adults. In contrast, GABA immunocytochemistry revealed
the presence of GABAergic perikarya and fibers in the pineal organ of late stage embryos and adults. Although high densities
of GABAergic cells were observed in the paracommissural pretectum, posterior tubercle, and tegmentum of dogfish embryos (regions
previously demonstrated to contain pinealopetal cells), the presence of GABA-ir perikarya in the pineal organ strongly suggests
that the rich GABAergic innervation of the elasmobranch pineal organ is intrinsic. This contrasts with the central origin
of GABAergic fibers in the pineal gland of some mammals.
This work was supported by the Spanish Education and Science Ministry and FEDER (BXX2000-0453-C02 and BFU2004-03313/BF1),
the Xunta de Galicia (PGIDT99BIO20002), and NIH/NIDCD awards R01 DC01705 and P01 DC01837 (to G.R.H.). 相似文献
22.
de Oliveira KB Guembarovski RL Oda JM Mantovani MS Carrera CM Reiche EM Voltarelli JC da Silva do Amaral Herrera AC Watanabe MA 《Cytokine》2011,55(2):260-265
The role of chemokines has been extensively analyzed both in cancer risk and tumor progression. Among different cytokines, CXCR4 and its ligand CXCL12 have been recently subjected to a closer examination. The single-nucleotide polymorphism (SNP) rs1801157 (previously known as CXCL12-A/SDF1-3'A) in the CXCL12 gene and the relative expression of mRNA CXCL12 in peripheral blood were assessed in breast cancer patients, since the chemokine CXCL12 and its receptor CXCR4 regulate leukocyte trafficking and many essential biological processes, including tumor growth, angiogenesis and metastasis of different types of tumors. Genotyping was performed by PCR-RFLP (polymerase chain reaction followed by restriction fragment length polymorphism) using MspI restriction enzyme and the expression analyses by quantitative RT-PCR. No difference in GG genotype and allele A carrier frequencies were observed between breast cancer patients and healthy blood donors and nor when CXCL12 mRNA expression was assessed among patients with different tumor stages. However a significant difference was observed when CXCL12 mRNA relative expression was analyzed in breast cancer patients in accordance to the presence or absence of the CXCL12 rs1801157 allele A. Allele A breast cancer patients presented a mRNA CXCL12 expression about 2.1-fold smaller than GG breast cancer patients. Estrogen positive patients presenting CXCL12 allele A presented a significantly lower expression of CXCL12 in peripheral blood (p=0.039) than GG hormone positive patients. Our findings demonstrated that allele A is associated with low expression of CXCL12 in the peripheral blood from ER-positive breast cancer patients, which suggests implications on breast cancer clinical outcome. 相似文献
23.
The size and density of microbial cells determine the time that pathogens can remain airborne and thus, their potential to
infect by the respiratory route. We determined the density and size distribution of Burkholderia pseudomallei cells in comparison with other Burkholderia species, including B. mallei and B. thailandensis, all prepared and analyzed under similar conditions. The observed size distribution and densities of several bacterial strains
indicates that aerosolized particles consisting of one or of a few B. pseudomallei cells should be efficiently retained in the lungs, highlighting the risk of transmission of melioidosis by the respiratory
route when the pathogen is present in fluids from infected patients or aerosolized from the environment. 相似文献
24.
Detection of nuclear lamin B epitopes in oocyte nuclei from mice, sea urchins, and clams using a human autoimmune serum 总被引:2,自引:0,他引:2
Somatic nuclei typically contain two or three major proteins, the lamins A, B, and C or their antigenically related equivalents, interspersed between the chromatin and its attachment site, the inner nuclear membrane. The late oocyte nuclear envelopes of the previously investigated Xenopus and Spisula germinal vesicles, however, have no chromatin attached and only one lamin-like protein. Since mouse and sea urchin germinal vesicles have chromatin attached, we tested them for the possible presence of more than one lamin. In both species we found two different lamins incorporated in their nuclear envelope structure. One lamin is recognized by anti-lamin B and the other by anti-lamin AC antibodies. Spisula germinal vesicles were found to contain not only the nuclear envelope-bound lamin (clamin), but also a 65-kDa protein cross-reactive with anti-lamin B antibodies. This protein is present unattached to any structure and is apparently soluble. Our findings provide a possible explanation of the early presence of lamin B in pronuclei of mouse and sea urchin contrary to the late appearance of a lamin B equivalent in amphibian embryos. In Spisula, as in Xenopus, the presence of a lamin B equivalent could not be documented in the nuclear envelopes of early embryos, indicating that a separate lamin B equivalent is not essential for chromatin binding to the envelope in these species during early embryogenesis. The results also indicate that the nuclear complement of structural proteins might vary substantially in the same cell type of different species. 相似文献
25.
26.
Ruizhi Wang Hongjie Wang Ivan Carrera Shaohua Xu Madepalli K. Lakshmana 《The Journal of biological chemistry》2015,290(14):9299-9309
Brain accumulation of neurotoxic amyloid β (Aβ) peptide because of increased processing of amyloid precursor protein (APP), resulting in loss of synapses and neurodegeneration, is central to the pathogenesis of Alzheimer disease (AD). Therefore, the identification of molecules that regulate Aβ generation and those that cause synaptic damage is crucial for future therapeutic approaches for AD. We demonstrated previously that COPS5 regulates Aβ generation in neuronal cell lines in a RanBP9-dependent manner. Consistent with the data from cell lines, even by 6 months, COPS5 overexpression in APΔE9 mice (APΔE9/COPS5-Tg) significantly increased Aβ40 levels by 32% (p < 0.01) in the cortex and by 28% (p < 0.01) in the hippocampus, whereas the increases for Aβ42 were 37% (p < 0.05) and 34% (p < 0.05), respectively. By 12 months, the increase was even more robust. Aβ40 levels increased by 63% (p < 0.001) in the cortex and by 65% (p < 0.001) in the hippocampus. Similarly, Aβ42 levels were increased by 69% (p < 0.001) in the cortex and by 71% (p < 0.011) in the hippocampus. Increased Aβ levels were translated into an increased amyloid plaque burden both in the cortex (54%, p < 0.01) and hippocampus (64%, p < 0.01). Interestingly, COPS5 overexpression increased RanBP9 levels in the brain, which, in turn, led to increased amyloidogenic processing of APP, as reflected by increased levels of sAPPβ and decreased levels of sAPPα. Furthermore, COPS5 overexpression reduced spinophilin in both the cortex (19%, p < 0.05) and the hippocampus (20%, p < 0.05), leading to significant deficits in learning and memory skills. Therefore, like RanBP9, COPS5 also plays a pivotal role in amyloid pathology in vivo. 相似文献
27.
A. F. Romero‐Caicedo P. Loor‐Andrade A. Cruz‐Martínez M. Carrera‐Fernández 《Zeitschrift fur angewandte Ichthyologie》2015,31(5):965-966
Weight–length relationships (WLR) were estimated for six batoids, namely: Urotrygon chilensis, Narcine entemedor, Rhinobatos leucorhynchus, Rhinobatos planiceps, Rhinobatos prahli and Urobatis tumbesensis captured in the Ecuadorian Pacific. Data were collected between October 2013 and August 2014 in two artisanal fishing ports. In addition, this represents the first WLR estimations for five of the species. 相似文献
28.
Production and turnover rates of shallow fine roots in rangelands of the Patagonian Monte, Argentina
Selective sheep grazing in arid rangelands induces a decrease in total cover and grass cover and an increase in the dominance
of shrubs. Both life forms differ in aboveground and belowground traits. We hypothesized that grazing disturbance leads to
the replacement of grass by shrub fine roots in the upper soil, and this is reflected in changes in the seasonal dynamics
of shallow fine roots at the community level. In two sites representative of non-grazed and grazed vegetation states in the
Patagonian Monte, we assessed the canopy structure, and the fine root biomass, N concentration, production, and turnover during
two consecutive years. The non-grazed site exhibited higher total, grass, and shrub cover than the grazed site. The grazed
site had larger or equal fine root biomass than the non-grazed site except for late spring of the second year. This could
be associated with the ability of shrubs to develop dimorphic-root systems occupying the soil freed by grasses at the grazed
site, and with the larger contribution of grass than shrub fine roots in relation to an extraordinary precipitation event
at the non-grazed site. This was consistent with the N concentration in fine roots. Fine root production was positively correlated
to temperature at the grazed site and with precipitation at the non-grazed site. Fine root turnover did not differ between
sites. Our results indicate that grazing leads to a shifting in the seasonality and main climatic controls of fine root production,
while fine root turnover is mostly affected by changes in soil water conditions. 相似文献
29.
The P450-4 Gene of Gibberella fujikuroi Encodes ent-Kaurene Oxidase in the Gibberellin Biosynthesis Pathway 总被引:1,自引:0,他引:1 下载免费PDF全文
Bettina Tudzynski Peter Hedden Esther Carrera Paul Gaskin 《Applied microbiology》2001,67(8):3514-3522
At least five genes of the gibberellin (GA) biosynthesis pathway are clustered on chromosome 4 of Gibberella fujikuroi; these genes encode the bifunctional ent-copalyl diphosphate synthase/ent-kaurene synthase, a GA-specific geranylgeranyl diphosphate synthase, and three cytochrome P450 monooxygenases. We now describe a fourth cytochrome P450 monooxygenase gene (P450-4). Gas chromatography-mass spectrometry analysis of extracts of mycelia and culture fluid of a P450-4 knockout mutant identified ent-kaurene as the only intermediate of the GA pathway. Incubations with radiolabeled precursors showed that the metabolism of ent-kaurene, ent-kaurenol, and ent-kaurenal was blocked in the transformants, whereas ent-kaurenoic acid was metabolized efficiently to GA4. The GA-deficient mutant strain SG139, which lacks the 30-kb GA biosynthesis gene cluster, converted ent-kaurene to ent-kaurenoic acid after transformation with P450-4. The B1-41a mutant, described as blocked between ent-kaurenal and ent-kaurenoic acid, was fully complemented by P450-4. There is a single nucleotide difference between the sequence of the B1-41a and wild-type P450-4 alleles at the 3′ consensus sequence of intron 2 in the mutant, resulting in reduced levels of active protein due to a splicing defect in the mutant. These data suggest that P450-4 encodes a multifunctional ent-kaurene oxidase catalyzing all three oxidation steps between ent-kaurene and ent-kaurenoic acid. 相似文献
30.
Hypoxia induces the activation of the phosphatidylinositol 3-kinase/Akt cell survival pathway in PC12 cells: protective role in apoptosis 总被引:4,自引:0,他引:4
Alvarez-Tejado M Naranjo-Suarez S Jiménez C Carrera AC Landázuri MO del Peso L 《The Journal of biological chemistry》2001,276(25):22368-22374
Hypoxia is a common environmental stress that influences signaling pathways and cell function. Several cell types, including neuroendocrine chromaffin cells, have evolved to sense oxygen levels and initiate specific adaptive responses to hypoxia. Here we report that under hypoxic conditions, rat pheochromocytoma PC12 cells are resistant to apoptosis induced by serum withdrawal and chemotherapy treatment. This effect is also observed after treatment with deferoxamine, a compound that mimics many of the effects of hypoxia. The hypoxia-dependent protection from apoptosis correlates with activation of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, which is detected after 3-4 h of hypoxic or deferoxamine treatment and is sustained while hypoxic conditions are maintained. Hypoxia-induced Akt activation can be prevented by treatment with cycloheximide or actinomycin D, suggesting that de novo protein synthesis is required. Finally, inhibition of PI3K impairs both the protection against apoptosis and the activation of Akt in response to hypoxia, suggesting a functional link between these two phenomena. Thus, reduced oxygen tension regulates apoptosis in PC12 cells through activation of the PI3K/Akt survival pathway. 相似文献