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排序方式: 共有899条查询结果,搜索用时 15 毫秒
1.
Gabrielle C. Winters Gianluca Polese Anna Di Cosmo Leonid L. Moroz 《Journal of morphology》2020,281(7):790-801
Neuropeptide Y (NPY) is an evolutionarily conserved neurosecretory molecule implicated in a diverse complement of functions across taxa and in regulating feeding behavior and reproductive maturation in Octopus. However, little is known about the precise molecular circuitry of NPY-mediated behaviors and physiological processes, which likely involve a complex interaction of multiple signal molecules in specific brain regions. Here, we examined the expression of NPY throughout the Octopus central nervous system. The sequence analysis of Octopus NPY precursor confirmed the presence of both, signal peptide and putative active peptides, which are highly conserved across bilaterians. In situ hybridization revealed distinct expression of NPY in specialized compartments, including potential “integration centers,” where visual, tactile, and other behavioral circuitries converge. These centers integrating separate circuits may maintain and modulate learning and memory or other behaviors not yet attributed to NPY-dependent modulation in Octopus. Extrasomatic localization of NPY mRNA in the neurites of specific neuron populations in the brain suggests a potential demand for immediate translation at synapses and a crucial temporal role for NPY in these cell populations. We also documented the presence of NPY mRNA in a small cell population in the olfactory lobe, which is a component of the Octopus feeding and reproductive control centers. However, the molecular mapping of NPY expression only partially overlapped with that produced by immunohistochemistry in previous studies. Our study provides a precise molecular map of NPY mRNA expression that can be used to design and test future hypotheses about molecular signaling in various Octopus behaviors. 相似文献
2.
Mouse heart laminin. Purification of the native protein and structural comparison with Engelbreth-Holm-Swarm tumor laminin 总被引:14,自引:0,他引:14
Laminin was selectively extracted from different mouse tissues using EDTA-containing buffer. By immunoblotting with an antiserum raised against mouse Engelbreth-Holm-Swarm (EHS) tumor laminin, such extracts could be shown to contain laminin-like molecules with a low apparent proportion of A chain to B chains. Native laminin was purified from mouse heart tissue and was shown to have an aberrant polypeptide composition as compared to mouse EHS tumor laminin. Most prominently, mouse heart laminin contains an Mr 300,000 polypeptide which is not antigenically related to the A or the B chains. Furthermore, nonreducible polypeptide components were seen with apparent Mr values of 600,000 and 900,000. The Mr 600,000 component contains epitopes shared with both EHS tumor laminin and the Mr 300,000 polypeptide and possibly represents a covalently cross-linked complex of an A or B chain with the Mr 300,000 chain. 相似文献
3.
Aleah Bowie Kara Walker Gabrielle Bunnell Dominique Morel Fanny Minesi Raphael Belais Brian Hare 《American journal of primatology》2021,83(1)
Poaching and habitat destruction in the Congo Basin threaten African great apes including the bonobo (Pan paniscus), chimpanzees (Pan troglodytes), and gorillas (Gorilla spp.) with extinction. One way to combat extinction is to reintroduce rescued and rehabilitated apes and repopulate native habitats. Reintroduction programs are only successful if they are supported by local populations. Ekolo ya Bonobo, located in Equateur province of the Democratic Republic of Congo (DRC), is the world's only reintroduction site for rehabilitated bonobos. Here we assess whether children, of the Ilonga‐Pôo, living adjacent to Ekolo ya Bonobo demonstrate more pro‐ape conservation attitudes than children living in, Kinshasa, the capital city. We examined children's attitudes toward great apes because children are typically the focus of conservation education programs. We used the Great Ape Attitude Questionnaire to test the Contact Hypothesis, which posits that proximity to great ape habitat influences pro‐conservation attitudes toward great apes. Ilonga‐Pôo children who live in closer contact with wild bonobos felt greater responsibility to protect great apes compared to those in Kinshasa who live outside the natural habitat of great apes. These results suggest that among participants in the DRC, spatial proximity to a species fosters a greater sense of responsibility to protect and conserve. These results have implications for the successful implementation of great ape reintroduction programs in the Congo Basin. The data analyzed in this study were collected in 2010 and therefore provide a baseline for longitudinal study of this reintroduction site. 相似文献
4.
J. J. M. Bergeron E. A. Craig A. L. Horwich T. Langer Gabrielle Multhoff D. F. Smith Lawrence E. Hightower 《Cell stress & chaperones》1997,2(4):220-228
No Abstract Available 相似文献
5.
Cutting edge: precursor frequency affects the helper dependence of cytotoxic T cells. 总被引:3,自引:0,他引:3
Justine D Mintern Gayle M Davey Gabrielle T Belz Francis R Carbone William R Heath 《Journal of immunology (Baltimore, Md. : 1950)》2002,168(3):977-980
Generation of CTL immunity often depends on the availability of CD4 T cell help. In this report, we show that CTL responses induced by cross-priming can be converted from CD4-dependent to CD4-independent by increasing the frequency of CTL precursors. In the absence of CD4 T cells, high numbers of CTL precursors were able to expand in number and become effector CTL. The ability of high frequencies of CD8 T cells to override help was not due to their ability to signal CD40 via expression of CD154. These findings suggest that when precursor frequencies are high, priming of CD8 T cell responses may not require CD4 T cell help. 相似文献
6.
Kinga Michno David Knight Jorge M. Campussano Diana van de Hoef Gabrielle L. Boulianne 《PloS one》2009,4(9)
Much of our current understanding about neurodegenerative diseases can be attributed to the study of inherited forms of these disorders. For example, mutations in the presenilin 1 and 2 genes have been linked to early onset familial forms of Alzheimer''s disease (FAD). Using the Drosophila central nervous system as a model we have investigated the role of presenilin in one of the earliest cellular defects associated with Alzheimer''s disease, intracellular calcium deregulation. We show that expression of either wild type or FAD-mutant presenilin in Drosophila CNS neurons has no impact on resting calcium levels but does give rise to deficits in intracellular calcium stores. Furthermore, we show that a loss-of-function mutation in calmodulin, a key regulator of intracellular calcium, can suppress presenilin-induced deficits in calcium stores. Our data support a model whereby presenilin plays a role in regulating intracellular calcium stores and demonstrate that Drosophila can be used to study the link between presenilin and calcium deregulation. 相似文献
7.
8.
TNF inhibitors are currently considered both effective and cost-effective in patients with active rheumatoid arthritis (RA),
particularly in patients who have not responded fully to methotrexate. There is substantial doubt about the cost-effectiveness
of TNF inhibitors as initial treatment for active RA. New data from the National Data Bank for Rheumatic Diseases now question
the current consensus in methotrexate failures. The data suggest that in routine clinical practice TNF inhibitors provide
only modest incremental benefits over best conventional therapy. If confirmed, these observational studies suggest that the
economic argument underpinning the widespread use of TNF inhibitors in established RA is unsustainable. 相似文献
9.
10.
Livia R. Tanjung Gabrielle Whittle Bruce E. Shaw Garry A. Bloomfield Margaret E. Katz Brian F. Cheetham 《Anaerobe》2009,15(5):219-224
The Gram-negative anaerobic pathogen Dichelobacter nodosus is the principal causative agent of footrot in sheep. The intA, intB and intC elements are mobile genetic elements which integrate into two tRNA genes downstream from csrA (formerly glpA) and pnpA in the D. nodosus chromosome. CsrA homologues act as global repressors of virulence in several bacterial pathogens, as does polynucleotide phosphorylase, the product of pnpA. We have proposed a model in which virulence in D. nodosus is controlled in part by the integration of genetic elements downstream from csrA and pnpA, altering the expression of these putative global regulators of virulence. We describe here a novel integrated genetic element, the intD element, which is 32 kb in size and contains an integrase gene, intD, several genes related to genes on other integrated elements of D. nodosus, a type IV secretion system and a putative mobilisation region, suggesting that the intD element has a role in the transfer of other genetic elements. Most of the D. nodosus strains examined which contained the intD gene were benign, with intD integrated next to pnpA, supporting our previous observation that virulent strains of D. nodosus have the intA element next to pnpA. 相似文献