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101.
102.
PAX3 Confers Functional Heterogeneity in Skeletal Muscle Stem Cell Responses to Environmental Stress
103.
Benzyl, benzoyl, and acetyl protected 1-OH and 1-SH glycoses in the glucose, glucosamine, galactose, mannose, and lactose series react with nitrobenzenes activated by one or two electron withdrawing substituents like nitro and cyano to afford the corresponding aryl glycosides in 50-100% yield. The S(N)Ar displacement of nitrite by 1-OH glycoses is reversible and gives predominantly the alpha-glycosides, whereas 1-SH glycoses do not anomerize and afford the beta-glycosides. Thus, the prepared dicyanophenyl gycosides are useful building blocks for the preparation of phthalocyanine-glycoconjugates via template synthesis. 相似文献
104.
Beinrohr L Harmat V Dobó J Lörincz Z Gál P Závodszky P 《The Journal of biological chemistry》2007,282(29):21100-21109
C1 inhibitor, a member of the serpin family, is a major down-regulator of inflammatory processes in blood. Genetic deficiency of C1 inhibitor results in hereditary angioedema, a dominantly inheritable, potentially lethal disease. Here we report the first crystal structure of the serpin domain of human C1 inhibitor, representing a previously unreported latent form, which explains functional consequences of several naturally occurring mutations, two of which are discussed in detail. The presented structure displays a novel conformation with a seven-stranded beta-sheet A. The unique conformation of the C-terminal six residues suggests its potential role as a barrier in the active-latent transition. On the basis of surface charge pattern, heparin affinity measurements, and docking of a heparin disaccharide, a heparin binding site is proposed in the contact area of the serpin-proteinase encounter complex. We show how polyanions change the activity of the C1 inhibitor by a novel "sandwich" mechanism, explaining earlier reaction kinetic and mutagenesis studies. These results may help to improve therapeutic C1 inhibitor preparations used in the treatment of hereditary angioedema, organ transplant rejection, and heart attack. 相似文献
105.
In vertebrates, multiple microsomal retinol dehydrogenases are involved in reversible retinol/retinal interconversion, thereby controlling retinoid metabolism and retinoic acid availability. The physiologic functions of these enzymes are not, however, fully understood, as each vertebrate form has several, usually overlapping, biochemical roles. Within this context, amphioxus, a group of chordates that are simpler, at both the functional and genomic levels, than vertebrates, provides a suitable evolutionary model for comparative studies of retinol dehydrogenase enzymes. In a previous study, we identified two amphioxus enzymes, Branchiostoma floridae retinol dehydrogenase 1 and retinol dehydrogenase 2, both candidates to be the cephalochordate orthologs of the vertebrate retinol dehydrogenase enzymes. We have now proceeded to characterize these amphioxus enzymes. Kinetic studies have revealed that retinol dehydrogenase 1 and retinol dehydrogenase 2 are microsomal proteins that catalyze the reduction of all-trans-retinaldehyde using NADH as cofactor, a remarkable combination of substrate and cofactor preferences. Moreover, evolutionary analysis, including the amphioxus sequences, indicates that Rdh genes were extensively duplicated after cephalochordate divergence, leading to the gene cluster organization found in several mammalian species. Overall, our data provide an evolutionary reference with which to better understand the origin, activity and evolution of retinol dehydrogenase enzymes. 相似文献
106.
Varga L Bíró A Széplaki G Tóth L Horváth A Füst G Farkas H 《Journal of cellular and molecular medicine》2007,11(6):1377-1383
Hereditary angioedema (HAE) is a rare disorder caused by the deficiency of the C1-inhibitor gene (C1INH) and characterized by recurrent bouts of angioedema. Autoimmune disorders frequently occur in HAE. Previously we found, that danazol has an adverse effect on serum lipid profile: reduced high-density lipoprotein (HDL) and elevated low-density lipoprotein (LDL) cholesterol levels are associated with long-term prophylactic use, whereas total cholesterol levels are unchanged. Our aim was to study the anti-cholesterol antibody (ACHA) production in HAE patients and compare it with those of healthy blood donors, and to investigate the possible associations between ACHA levels and serum lipid profile alterations caused by danazol. Anti-cholesterol IgG levels were measured by ELISA and their correlation with serum concentrations of total cholesterol, HDL, LDL, triglycerides was determined in HAE patients receiving/not receiving danazol. Serum ACHA levels were significantly higher in HAE patients, compared to healthy blood donors (P<0.0001). Longterm danazol prophylaxis had no effect on serum ACHA levels in HAE patients. However, we found a significant, negative correlation between ACHA levels and serum total cholesterol (r=-0.4033, P=0.0200), LDL (r=-0.4565, P=0.0076) and triglyceride (r=-0.4230, P=0.0121) levels only in danazol-treated patients, but not in HAE patients who did not receive long-term prophylaxis. Patients with HAE have higher baseline ACHA levels compared to healthy subjects, and this might reflect polyclonal B-cell activation. The latter would be a potential explanation for the lack of an increased incidence of infectious diseases in HAE patients, but might lead to increased autoimmunity. 相似文献
107.
Gene expression dynamics in deer antler: mesenchymal differentiation toward chondrogenesis 总被引:6,自引:0,他引:6
Gyurján I Molnár A Borsy A Stéger V Hackler L Zomborszky Z Papp P Duda E Deák F Lakatos P Puskás LG Orosz L 《Molecular genetics and genomics : MGG》2007,277(3):221-235
Annual re-growth of deer antler represents a unique example of complete organ regeneration. Because antler mesenchymal cells
retain their embryonic capacity to develop into cartilage or bone, studying antler development provides a natural system to
follow gene expression changes during mesenchymal differentiation toward chondrogenic/osteogenic lineage. To identify novel
genes involved either in early events of mesenchymal cell specialization or in robust bone development, we have introduced
a 3 K heterologous microarray set-up (deer cDNA versus mouse template). Fifteen genes were differentially expressed; genes
for housekeeping, regulatory functions (components of different signaling pathways, including FGF, TGFβ, Wnt), and genes encoding
members of the Polycomb group were represented. Expression dynamics for genes are visualized by an expression logo. The expression
profile of the gene C21orf70 of unknown function is described along with the effects when over-expressed; furthermore the nuclear localization of the
cognate protein is shown. In this report, we demonstrate the particular advantage of the velvet antler model in bone research
for: (1) identification of mesenchymal and precartilaginous genes and (2) targeting genes upregulated in robust cartilage
development.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
108.
Lysine-8-vasopressin (LVP) was injected into the lateral ventricle (ICV) or into the cisterna magna (c.m.) of ether-anesthetized rats. ICV injection of LVP decreased the blood pressure (BP), whereas c.m. administration increased it. The opposite effects of ICV versus c.m. administration of the peptide might be related to differences in brainstem versus limbic-midbrain structures in the regulation of blood pressure, and suggest that both mechanisms can be influenced by vasopressin. 相似文献
109.
Cubarsí R Carrió MM Villaverde A 《Biochemical and biophysical research communications》2001,282(2):436-441
Misfolded proteins undergo a preferent degradation ruled by the housekeeping bacterial proteolytic system, but upon precipitation as inclusion bodies their stability dramatically increases. The susceptibility of aggregated polypeptides to proteolytic attack remains essentially unexplored in bacteria and also in eukaryotic cells. We have studied here the in vitro proteolysis of beta-galactosidase fusion proteins by trypsin treatment of purified inclusion bodies. A cascade digestion process similar to that occurring in vivo has been observed in the insoluble fraction of the digestion reaction. This suggests that major protease target sites are not either lost or newly generated by protein precipitation and that the digestion occurs in situ probably on solvent-exposed surfaces of inclusion bodies. In addition, the sequence of the proteolytic attack is influenced by protein determinants other than amino acid sequence, the early digestion steps having a dramatic influence on the further cleavage susceptibility of the intermediate degradation fragments. These observations indicate unexpected conformational changes of inclusion body proteins during their site-limited digestion, that could promote protein release from aggregates, thus partially accounting for the plasticity of in vivo protein precipitation and solubilization in bacteria. 相似文献
110.
Expression of functional chemokine receptors CXCR3 and CXCR4 on human melanoma cells 总被引:17,自引:0,他引:17
Robledo MM Bartolome RA Longo N Rodríguez-Frade JM Mellado M Longo I van Muijen GN Sánchez-Mateos P Teixidó J 《The Journal of biological chemistry》2001,276(48):45098-45105
Chemokines are secreted into the tumor microenvironment by tumor-infiltrating inflammatory cells as well as by tumor cells. Chemokine receptors mediate agonist-dependent cell responses, including migration and activation of several signaling pathways. In the present study we show that several human melanoma cell lines and melanoma cells on macroscopically infiltrated lymph nodes express the chemokine receptors CXCR3 and CXCR4. Using the highly invasive melanoma cell line BLM, we demonstrate that the chemokine Mig, a ligand for CXCR3, activates the small GTPases RhoA and Rac1, induces a reorganization of the actin cytoskeleton, and triggers cell chemotaxis and modulation of integrin VLA-5- and VLA-4-dependent cell adhesion to fibronectin. Furthermore, the chemokine SDF-1alpha, the ligand of CXCR4, triggered modulation of beta(1) integrin-dependent melanoma cell adhesion to fibronectin. Additionally, Mig and SDF-1alpha activated MAPKs p44/42 and p38 on melanoma cells. Expression of functional CXCR3 and CXCR4 receptors on melanoma cells indicates that they might contribute to cell motility during invasion as well as to regulation of cell proliferation and survival. 相似文献