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531.
532.
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534.
Climate change: models change their tune 总被引:1,自引:0,他引:1
Stocker TF 《Nature》2004,430(7001):737-738
535.
Cecchi C Liguri G Fiorillo C Bogani F Gambassi M Giannoni E Cirri P Baglioni S Ramponi G 《Cellular and molecular life sciences : CMLS》2004,61(14):1775-1784
An acylphosphatase (AcPase) overexpression study was carried out on SH-SY5Y neuroblastoma cells, using a
green fluorescent fusion protein (AcP-GFP), with GFP acting as a reporter protein. The cellular proliferation rate
was significantly reduced by overexpression of AcPase by a factor of ten. In contrast, clones transfected with two
inactive AcPase mutants showed a growth rate comparable to control cells. This suggests that AcPase catalyzes the
proliferative down-regulation. AcPase-overexpressing clones showed a physiological mortality rate as assessed by an
MTT reduction test and by evaluation of necrotic markers. DNA fragmentation analysis and assays of caspase-3 and
poly (ADP-ribose) polymerase (PARP)-active fragments showed no evidence of any apoptotic pattern. AcPase
overexpression led to a marked increase in PARP activity as well as Bcl-2 content; these are commonly up-regulated
during differentiative processes in neuronal cells. In fact, the typical differentiation marker,
growth-associated-protein 43, was significantly up-regulated. Microscopic observations also showed a clear
increase in the differentiative phenotype in AcPase-overexpressing cells. Our results clearly show that AcPase
plays a primary causative role in neuronal differentiation.Received 3 May 2004; accepted 25 May 2004 相似文献
536.
Involvement of penaeidins in defense reactions of the shrimp Litopenaeus stylirostris to a pathogenic vibrio 总被引:2,自引:0,他引:2
Munoz M Vandenbulcke F Garnier J Gueguen Y Bulet P Saulnier D Bachère E 《Cellular and molecular life sciences : CMLS》2004,61(7-8):961-972
The present study reports for the first time the involvement of an antimicrobial peptide in the defense reactions of a shrimp infected by a pathogenic Vibrio, Vibrio penaeicida. New members of the penaeidin family were characterized in the shrimp Litopenaeus stylirostris by RT-PCR and RACE-PCR from hemocyte total RNAs, and by mass spectrometry detection and immunolocalization of mature peptides in shrimp hemocytes. In infected shrimps, bacteria and penaeidin distribution colocalized in the gills and the lymphoid organ that represented the main infected sites. Moreover, the shrimp immune response to infection involved massive hemocyte recruitment to infection sites where released penaeidin may participate in the isolation and elimination of the bacteria, We show that the ability of the shrimps to circumvent shrimp infections is closely related to a recovery phase based on the hematopoietic process.Received 25 November 2003; received after revision 8 January 2004; accepted 21 January 2004 相似文献
537.
538.
Profiling of the secreted proteins during 3T3-L1 adipocyte differentiation leads to the identification of novel adipokines 总被引:3,自引:0,他引:3
Wang P Mariman E Keijer J Bouwman F Noben JP Robben J Renes J 《Cellular and molecular life sciences : CMLS》2004,61(18):2405-2417
Adipose tissue is an endocrine organ capable of secreting a number of adipokines with a role in the regulation of
adipose tissue and whole-body metabolism. We used two-dimensional gel electrophoresis combined with mass spectrometry to
profile the secreted proteins from (pre)adipocytes. The culture medium of 3T3-L1 cells during adipocyte differentiation
was screened, and 41 proteins that responded to blocking of secretion by 20°C treatment and/or brefeldin A treatment
were identified. Prohibitin, stress-70 protein, and adhesion-regulating molecule 1 are reported for the first time as
secreted proteins. In addition, procollagen C-proteinase enhancer protein, galectin-1, cyclophilin A and C, and SF20/IL-25
are newly identified as adipocyte secreted factors. Secretion profiles indicated a dynamic environment including an
actively remodeling extracellular matrix and several factors involved in growth regulation.Received 15 June 2004; received after revision 26 July 2004; accepted 2 August 2004 相似文献
539.
540.
Novel aspects of glypican glycobiology 总被引:5,自引:0,他引:5
Fransson LA Belting M Cheng F Jönsson M Mani K Sandgren S 《Cellular and molecular life sciences : CMLS》2004,61(9):1016-1024
Mutations in glypican genes cause dysmorphic and overgrowth syndromes in men and mice, abnormal development in flies and worms, and defective gastrulation in zebrafish and ascidians. All glypican core proteins share a characteristic pattern of 14 conserved cysteine residues. Upstream from the C-terminal membrane anchorage are 3–4 heparan sulfate attachment sites. Cysteines in glypican-1 can become nitrosylated by nitric oxide in a copper-dependent reaction. When glypican-1 is exposed to ascorbate, nitric oxide is released and participates in deaminative cleavage of heparan sulfate at sites where the glucosamines have a free amino group. This process takes place while glypican-1 recycles via a nonclassical, caveolin-1-associated route. Glypicans are involved in growth factor signalling and transport, e.g. of polyamines. Cargo can be unloaded from heparan sulfate by nitric oxide-dependent degradation. How glypican and its degradation products and the cargo exit from the recycling route is an enigma.Received 27 November 2003; received after revision 8 January 2004; accepted 13 January 2004 相似文献