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81.
Gutiérrez-López MD Gilsanz A Yáñez-Mó M Ovalle S Lafuente EM Domínguez C Monk PN González-Alvaro I Sánchez-Madrid F Cabañas C 《Cellular and molecular life sciences : CMLS》2011,68(19):3275-3292
ADAM17/TACE is a metalloproteinase responsible for the shedding of the proinflammatory cytokine TNF-α and many other cell
surface proteins involved in development, cell adhesion, migration, differentiation, and proliferation. Despite the important
biological function of ADAM17, the mechanisms of regulation of its metalloproteinase activity remain largely unknown. We report
here that the tetraspanin CD9 and ADAM17 partially co-localize on the surface of endothelial and monocytic cells. In situ
proximity ligation, co-immunoprecipitation, crosslinking, and pull-down experiments collectively demonstrate a direct association
between these molecules. Functional studies reveal that treatment with CD9-specific antibodies or neoexpression of CD9 exert
negative regulatory effects on ADAM17 sheddase activity. Conversely, CD9 silencing increased the activity of ADAM17 against
its substrates TNF-α and ICAM-1. Taken together, our results show that CD9 associates with ADAM17 and, through this interaction,
negatively regulates the sheddase activity of ADAM17. 相似文献
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84.
Amiot L Ferrone S Grosse-Wilde H Seliger B 《Cellular and molecular life sciences : CMLS》2011,68(3):417-431
Although the expression of the non-classical HLA class I molecule HLA-G was first reported to be restricted to the fetal–maternal
interface on the extravillous cytotrophoblasts, the distribution of HLA-G in normal tissues appears broader than originally
described. HLA-G expression was found in embryonic tissues, in adult immune privileged organs, and in cells of the hematopoietic
lineage. More interestingly, under pathophysiological conditions HLA-G antigens may be expressed on various types of malignant
cells suggesting that HLA-G antigen expression is one strategy used by tumor cells to escape immune surveillance. In this
article, we will focus on HLA-G expression in cancers of distinct histology and its association with the clinical course of
diseases, on the underlying molecular mechanisms of impaired HLA-G expression, on the immune tolerant function of HLA-G in
tumors, and on the use of membrane-bound and soluble HLA-G as a diagnostic or prognostic biomarker to identify tumors and
to monitor disease stage, as well as on the use of HLA-G as a novel therapeutic target in cancer. 相似文献
85.
Biegel E Schmidt S González JM Müller V 《Cellular and molecular life sciences : CMLS》2011,68(4):613-634
Microbes have a fascinating repertoire of bioenergetic enzymes and a huge variety of electron transport chains to cope with
very different environmental conditions, such as different oxygen concentrations, different electron acceptors, pH and salinity.
However, all these electron transport chains cover the redox span from NADH + H+ as the most negative donor to oxygen/H2O as the most positive acceptor or increments thereof. The redox range more negative than −320 mV has been largely ignored.
Here, we have summarized the recent data that unraveled a novel ion-motive electron transport chain, the Rnf complex, that
energetically couples the cellular ferredoxin to the pyridine nucleotide pool. The energetics of the complex and its biochemistry,
as well as its evolution and cellular function in different microbes, is discussed. 相似文献
86.
Rai A Nöthe H Tzvetkov N Korenbaum E Manstein DJ 《Cellular and molecular life sciences : CMLS》2011,68(16):2751-2767
Dictyostelium discoideum cells produce five dynamin family proteins. Here, we show that dynamin B is the only member of this group of proteins that
is initially produced as a preprotein and requires processing by mitochondrial proteases for formation of the mature protein.
Our results show that dynamin B-depletion affects many aspects of cell motility, cell-cell and cell-surface adhesion, resistance
to osmotic shock, and fatty acid metabolism. The mature form of dynamin B mediates a wide range and unique combination of
functions. Dynamin B affects events at the plasma membrane, peroxisomes, the contractile vacuole system, components of the
actin-based cytoskeleton, and cell adhesion sites. The modulating effect of dynamin B on the activity of the contractile vacuole
system is unique for the Dictyostelium system. Other functions displayed by dynamin B are commonly associated with either classical dynamins or dynamin-related
proteins. 相似文献
87.
Repair of wounds usually results in restoration of organ function, even if suboptimal. However, in a minority of situations,
the healing process leads to significant scarring that hampers homeostasis and leaves the tissue compromised. This scar is
characterized by an excess of matrix deposition that remains poorly organized and weakened. While we know much of the early
stages of the repair process, the transition to wound resolution that limits scar formation is poorly understood. This is
particularly true of the inducers of scar formation. Here, we present a hypothesis that it is the matrix itself that is a
primary driver of scar, rather than being simply the result of other cellular dysregulations. 相似文献
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Root nodule (RN) symbiosis has a unique feature in which symbiotic bacteria fix atmospheric nitrogen. The symbiosis is established
with a limited species of land plants, including legumes. How RN symbiosis evolved is still a mystery, but recent findings
on legumes genes that are necessary for RN symbiosis may give us a clue. 相似文献
90.