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991.
Chlebova K Bryja V Dvorak P Kozubik A Wilcox WR Krejci P 《Cellular and molecular life sciences : CMLS》2009,66(2):225-235
Fibroblast growth factor 2 (FGF2) is one of the most studied growth factors to date. Most attention has been dedicated to
the smallest, 18kDa FGF2 variant that is released by cells and acts through activation of cell-surface FGF-receptor tyrosine
kinases. There are, however, several higher molecular weight (HMW) variants of FGF2 that rarely leave their producing cells,
are retained in the nucleus and act independently of FGF-receptors (FGFR). Despite significant evidence documenting the expression
and intracellular trafficking of HMW FGF2, many important questions remain about the physiological roles and mechanisms of
action of HMW FGF2. In this review, we summarize the current knowledge about the biology of HMW FGF2, its role in disease
and areas for future investigation.
Received 28 July 2008; received after revision 18 August 2008; accepted 22 August 2008 相似文献
992.
Eukaryotic genomes have complex spatial organization in the nucleus. The factors and the mechanisms involved in this organization
remain an enigma. Among the many proteins implicated in such a role, the ubiquitous Zn-finger protein CTCF stands out. Here
we summarize the evidence placing CTCF in the enviable position of a master organizer of the genome. CTCF can form loops in cis, and can bridge sequences located on different chromosomes in trans. The thousands of CTCF binding sites, identified in recent genome-wide localization studies, and their distribution along
the genome further support a crucial role of CTCF as a chromatin organizer.
Received 10 October 2008; received after revision 11 December 2008; accepted 16 December 2008 相似文献
993.
S. M. Houten M. Chegary H. te Brinke W. J. Wijnen J. F. C. Glatz J. J. F. P. Luiken F. A. Wijburg R. J. A. Wanders 《Cellular and molecular life sciences : CMLS》2009,66(7):1283-1294
Organs are flexible as to which substrates they will use to maintain energy homeostasis. Under well-fed conditions, glucose
is a preferred substrate for oxidation. During fasting, fatty acid oxidation will become a more important energy source. Glucose
oxidation is decreased by fatty acids, a process in which the pyruvate dehydrogenase complex (PDH) and its regulator pyruvate
dehydrogenase kinase 4 (PDK4) play important roles. It is currently unknown how energy status influences PDH activity. We
show that AMP-activated protein kinase (AMPK) activation by hypoxia and AICAR treatment combined with fatty acid administration
synergistically induce PDK4 expression. We provide evidence that AMPK activation modulates ligand-dependent activation of
peroxisome proliferator-activated receptor. Finally, we show that this synergistic induction of PDK4 decreases cellular glucose
oxidation. In conclusion, AMPK and fatty acids play a direct role in fuel selection in response to cellular energy status
in order to spare glucose.
S. M. Houten, M. Chegary: These two authors contributed equally to this work.
Received 11 July 2008; received after revision 26 January 2009; accepted 02 February 2009 相似文献
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996.
Antisense transcription: A critical look in both directions 总被引:3,自引:1,他引:2
997.
D. E. Dye S. Karlen B. Rohrbach O. Staub L. R. Braathen K. A. Eidne D. R. Coombe 《Cellular and molecular life sciences : CMLS》2009,66(4):681-696
hShroom1 (hShrm1) is a member of the Apx/Shroom (Shrm) protein family and was identified from a yeast two-hybrid screen as
a protein that interacts with the cytoplasmic domain of melanoma cell adhesion molecule (MCAM). The characteristic signature
of the Shrm family is the presence of a unique domain, ASD2 (Apx/Shroom domain 2). mRNA analysis suggests that hShrm1 is expressed
in brain, heart, skeletal muscle, colon, small intestine, kidney, placenta and lung tissue, as well a variety of melanoma
and other cell lines. Co-immunoprecipitation and bioluminescence resonance energy transfer (BRET) experiments indicate that
hShrm1 and MCAM interact in vivo and by immunofluorescence microscopy some co-localization of these proteins is observed. hShrm1 partly co-localises with
β-actin and is found in the Triton X-100 insoluble fraction of melanoma cell extracts. We propose that hShrm1 is involved
in linking MCAM to the cytoskeleton.
D. E. Dye, S. Karlen: These authors contributed equally to this work.
Received 09 October 2008; received after revision 23 November 2008; accepted 09 December 2008 相似文献
998.
Cutaneous wound healing is a complex and highly coordinated process where a number of different cell types participate to
renew the damaged tissue under the strict regulation of soluble and insoluble factors. One of the most versatile processes
involved in wound repair is proteolysis. During cell migration, proteins of extracellular matrix are cleaved, often creating
biologically active cleavage products, and proteolysis of cellular contacts leads to increased cell motility and division.
Moreover, proteases activate various growth factors and other proteases in wound and regulate growth factor signaling by shedding
growth factor receptors on cell surface. Normally, proteolysis is strictly controlled, and changes in protease activity are
associated with alterations in wound closure and scar formation. Here, we present the current view on the role of metalloproteinases
and the plasmin-plasminogen system in normal and aberrant cutaneous wound repair and discuss their role as potential therapeutic
targets for chronic ulcers or fibrotic scars.
Received 07 July 2008; received after revision 11 August 2008; accepted 13 August 2008 相似文献
999.
A Multiplicative Error Model with Heterogeneous Components for Forecasting Realized Volatility
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To forecast realized volatility, this paper introduces a multiplicative error model that incorporates heterogeneous components: weekly and monthly realized volatility measures. While the model captures the long‐memory property, estimation simply proceeds using quasi‐maximum likelihood estimation. This paper investigates its forecasting ability using the realized kernels of 34 different assets provided by the Oxford‐Man Institute's Realized Library. The model outperforms benchmark models such as ARFIMA, HAR, Log‐HAR and HEAVY‐RM in within‐sample fitting and out‐of‐sample (1‐, 10‐ and 22‐step) forecasts. It performed best in both pointwise and cumulative comparisons of multi‐step‐ahead forecasts, regardless of loss function (QLIKE or MSE). Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
1000.