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James E. Swain Richard Robitaille Gavin R. Dass Milton P. Charlton 《Developmental neurobiology》1991,22(8):855-864
We examined the role of phosphatases in synaptic transmission using the permeant phosphatase inhibitor okadaic acid (OA). In the crayfish neuromuscular junction (NMJ), postsynaptic effects including increases in input resistance occurred at doses greater than 5 μM OA. At lower doses (0.5–5 μM) the effects were solely presynaptic and transmitter release increased over three-fold despite small reductions in amplitude and duration of presynaptic action potentials. Potentiating effects of serotonin on transmitter release, Which depend on phosphorylation, were increased by OA. Frequency facilitation was reduced but its decay was not affected. In frog NMJs, OA increased spontaneous and evoked release two-fold through presynaptic mechanisms. An inactive analog of OA, OA tetra-acetate, had no effect on transmitter release at frog and crayfish NMJ. Therefore, phosphatases have a strong modulating influence on synaptic transmission. 相似文献
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Jye-Lin Hsu Dick J. H. van den Boomen Peter Tomasec Michael P. Weekes Robin Antrobus Richard J. Stanton Eva Ruckova Daniel Sugrue Gavin S. Wilkie Andrew J. Davison Gavin W. G. Wilkinson Paul J. Lehner 《PLoS pathogens》2015,11(4)
Human cytomegalovirus (HCMV) US2, US3, US6 and US11 act in concert to prevent immune recognition of virally infected cells by CD8+ T-lymphocytes through downregulation of MHC class I molecules (MHC-I). Here we show that US2 function goes far beyond MHC-I degradation. A systematic proteomic study using Plasma Membrane Profiling revealed US2 was unique in downregulating additional cellular targets, including: five distinct integrin α-chains, CD112, the interleukin-12 receptor, PTPRJ and thrombomodulin. US2 recruited the cellular E3 ligase TRC8 to direct the proteasomal degradation of all its targets, reminiscent of its degradation of MHC-I. Whereas integrin α-chains were selectively degraded, their integrin β1 binding partner accumulated in the ER. Consequently integrin signaling, cell adhesion and migration were strongly suppressed. US2 was necessary and sufficient for degradation of the majority of its substrates, but remarkably, the HCMV NK cell evasion function UL141 requisitioned US2 to enhance downregulation of the NK cell ligand CD112. UL141 retained CD112 in the ER from where US2 promoted its TRC8-dependent retrotranslocation and degradation. These findings redefine US2 as a multifunctional degradation hub which, through recruitment of the cellular E3 ligase TRC8, modulates diverse immune pathways involved in antigen presentation, NK cell activation, migration and coagulation; and highlight US2’s impact on HCMV pathogenesis. 相似文献
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Wanwisa Dejnirattisai Daming Zhou Helen M. Ginn Helen M.E. Duyvesteyn Piyada Supasa James Brett Case Yuguang Zhao Thomas S. Walter Alexander J. Mentzer Chang Liu Beibei Wang Guido C. Paesen Jose Slon-Campos César López-Camacho Natasha M. Kafai Adam L. Bailey Rita E. Chen Baoling Ying Gavin R. Screaton 《Cell》2021,184(8):2183-2200.e22
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B. K. Pierson S. J. Giovannoni D. A. Stahl R. W. Castenholz 《Archives of microbiology》1985,142(2):164-167
An unusual filamentous, gliding bacterium was found in a few hot springs in Oregon where it formed a nearly unispecific top layer of microbial mats. It contained a bacteriochlorophyll a-like pigment and an abundance of carotenoids. There were no chlorosomes or additional chlorophylls. The organism was aerotolerant and appeared to be photoheterotrophic. It was successfully co-cultured with an aerobic chemoheterotroph in a medium containing glucose and casamino acids. Although it has many characteristics in common with the genus Chloroflexus, the lack of chlorosomes and bacteriochlorophyll c and the aerobic nature of this organism indicate that it should be placed in a new genus. This conclusion is supported by 5S rRNA nucleotide sequence data. 相似文献
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Riccardo Danielli Roberto Patuzzo Anna Maria Di Giacomo Gianfranco Gallino Andrea Maurichi Annabella Di Florio Ornella Cutaia Andrea Lazzeri Carolina Fazio Clelia Miracco Leonardo Giovannoni Giuliano Elia Dario Neri Michele Maio Mario Santinami 《Cancer immunology, immunotherapy : CII》2015,64(8):999-1009
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Essential Role for the Lymphostromal Plasma Membrane Ly-6 Superfamily Molecule Thymic Shared Antigen 1 in Development of the Embryonic Adrenal Gland 下载免费PDF全文
David J. Zammit Stuart P. Berzins Jason W. Gill Elise S. Randle-Barrett Louise Barnett Frank Koentgen Gavin W. Lambert Richard P. Harvey Richard L. Boyd Brendan J. Classon 《Molecular and cellular biology》2002,22(3):946-952
Thymic shared antigen 1 (TSA-1) is a plasma membrane protein of the Ly-6 superfamily expressed on thymocytes, thymic stromal cells, and other cells of the hematopoietic system. TSA-1 is also expressed in other nonhematopoietic tissues, in particular, embryonic and adult adrenal glands. To address the function of TSA-1, we generated mutant mice in which TSA-1 expression was inactivated by gene targeting. Here we show that deletion of both TSA-1 alleles results in abnormal adrenal gland development and midgestational lethality due to cardiac abnormalities. We also report that TSA-1-deficient adrenal glands have significantly reduced levels of the catecholamines noradrenaline and adrenaline. We conclude that TSA-1 is required for normal embryonic development but that deletion of its expression does not obviously impair lymphoid development. 相似文献