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551.
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Daniel G. Tenen Lora L. Haines David M. Livingston 《Journal of molecular biology》1982,157(3):473-492
DNAase footprint analyses of purified AD2 + D2 (D2) T protein binding to simian virus 40 origin region fragments revealed a series of four specific interactions with contiguous sequences constituting a 120 base-pair block, in keeping with previous DNAase protection results reported by others. Protection was observed to extend from a 30 base-pair strong affinity site located on the early side of the replication origin (site 1) to two adjacent lower affinity sites, including the origin of replication (site 2) and a 11 to 13 base-pair site between site 1 and the beginning of the T/t coding sequence (site 1′). A fourth site (site 3) was noted abutting the late border of site 2. Binding to site 1 was associated with enhanced D2T binding to sites 2 and 1′. Thus, binding to these sites is co-operative and/or the sequences which constitute site 1 affect the conformation of the sites 1′ and 2 sequences such that they now serve as sites of more efficient D2T binding. In addition, while deletion of all of site 2 and its substitution by late viral sequences ablated processive T binding to sequences abutting site 1 on its late side, various site 2 deletions comprising up to approximately 40% of that sequence did not affect binding to that site to a major degree. Therefore, binding to the replication origin is a sequence-specific event, but there may be multiple strong protein contact sites within that sequence. 相似文献
554.
555.
John Livingston 《BMJ (Clinical research ed.)》1905,1(2316):1127-1128
556.
Dudley H. McNitt Soo Jeon Choi Jessica L. Allen River A. Hames Scott A. Weed Livingston Van De Water Rita Berisio Slawomir Lukomski 《Molecular microbiology》2019,112(3):800-819
The human‐adapted pathogen group A Streptococcus (GAS) utilizes wounds as portals of entry into host tissue, wherein surface adhesins interact with the extracellular matrix, enabling bacterial colonization. The streptococcal collagen‐like protein 1 (Scl1) is a major adhesin of GAS that selectively binds to two fibronectin type III (FnIII) repeats within cellular fibronectin, specifically the alternatively spliced extra domains A and B, and the FnIII repeats within tenascin‐C. Binding to FnIII repeats was mediated through conserved structural determinants present within the Scl1 globular domain and facilitated GAS adherence and biofilm formation. Isoforms of cellular fibronectin that contain extra domains A and B, as well as tenascin‐C, are present for several days in the wound extracellular matrix. Scl1‐FnIII binding is therefore an example of GAS adaptation to the host's wound environment. Similarly, cellular fibronectin isoforms and tenascin‐C are present in the tumor microenvironment. Consistent with this, FnIII repeats mediate GAS attachment to and enhancement of biofilm formation on matrices deposited by cancer‐associated fibroblasts and osteosarcoma cells. These data collectively support the premise for utilization of the Scl1‐FnIII interaction as a novel method of anti‐neoplastic targeting in the tumor microenvironment. 相似文献
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558.
Dr. A. Livingston 《Cell and tissue research》1978,191(3):501-506
Summary Neural lobes from rats subjected to neurohypophysial hormone-releasing stimuli were examined electron microscopically following fixation in 4 % tannic acid in 2.5 % glutaraldehyde. This fixation allowed the delineation of the perivascular space in the neural lobe tissue. Measurement of the area of the perivascular space showed that it was significantly increased in the rats subjected to vagal stimulation and intraarterial calcium ions compared to the control rats. The rats which had been subjected to haemorrhage as a hormonereleasing stimulus did not show any significant change in the area of the perivascular space. The significance of these findings in relation to hormone release is discussed. 相似文献
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Mariana Capurro Laura Bover Paula Portela Philip Livingston J. Mordoh 《Cancer immunology, immunotherapy : CII》1998,45(6):334-339
FC-2.15 is a murine IgM monoclonal antibody that recognizes breast and colon human carcinomas, chronic myeloid leukemias,
Sternberg cells of Hodgkin’s lymphoma and some normal cells, such as peripheral polymorphonuclear granulocytes. It has been
previously demonstrated that FC-2.15 recognizes the carbohydrate moiety of different glycoproteins. FC-2.15 is able to mediate
the in vitro lysis of Ag-2.15+ cells by human complement. In a phase I clinical trial, FC-2.15 induced antitumor responses and reversible neutropenia was
its main toxicity. In this work, analysis of epitope specificity has demonstrated that FC-2.15 specifically recognizes terminally
exposed Lewisx trisaccharide but not sialyl-Lewisx, Lewisa, trifucosylated Lewisy, blood-group antigens A and B, globo H and gangliosides. In polymorphonuclear granulocytes (PMN), myeloid leukemic cells
and colon carcinoma T84 cells, Lewisx was found to be almost exclusively N-linked to the protein core, whereas in breast carcinoma MCF-7 cells, Lewisx appeared to be mostly O-linked. Treatment with neuraminidase increased detection by FC-2.15 in normal PMN, myeloid leukemia
cells and T84 cells but not in MCF-7 cells.
Received: 20 March 1997 / Accepted: 4 September 1997 相似文献