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121.
122.
Scorpio A Blank TE Day WA Chabot DJ 《Cellular and molecular life sciences : CMLS》2006,63(19-20):2237-2248
Anthrax has been a major cause of death in grazing animals and an occasional cause of death in humans for thousands of years. Since the late 1800s there has been an exceptional international history of anthrax vaccine development. Due to animal vaccinations, the rate of infection has dropped dramatically. Anthrax vaccines have progressed from uncharacterized whole-cell vaccines in 1881, to pXO2-negative spores in the 1930s, to culture filtrates absorbed to aluminum hydroxide in 1970, and likely to recombinant protective antigen in the near future. Each of these refinements has increased safety without significant loss of efficacy. The threat of genetically engineered, antibiotic and vaccine resistant strains of Bacillus anthracis is fueling hypothesis-driven research and global techniques--including genomics, proteomics and transposon site hybridization--to facilitate the discovery of novel vaccine targets. This review highlights historical achievements and new developments in anthrax vaccine research. 相似文献
123.
Structural and biological aspects of carotenoid cleavage 总被引:1,自引:0,他引:1
Apo-carotenoid compounds such as retinol (vitamin A) are involved in a variety of cellular processes and are found in all kingdoms of life. Instead of being synthesized from small precursors, they are commonly produced by oxidative cleavage and subsequent modification of larger carotenoid compounds. The cleavage reaction is catalyzed by a family of related enzymes, which convert specific substrate double bonds to the corresponding aldehydes or ketones. The individual family members differ in their substrate preference and the position of the cleaved double bond, giving rise to a remarkable number of products starting from a limited number of carotenoid substrate molecules. The recent determination of the structure of a member of this family has provided insight into the reaction mechanism, showing how substrate specificity is achieved. This review will focus on the biochemistry of carotenoid oxygenases and the structural determinants of the cleavage reaction. 相似文献
124.
125.
Gereben B Zeöld A Dentice M Salvatore D Bianco AC 《Cellular and molecular life sciences : CMLS》2008,65(4):570-590
The thyroid hormone plays a fundamental role in the development, growth, and metabolic homeostasis in all vertebrates by affecting
the expression of different sets of genes. A group of thioredoxin fold-containing selenoproteins known as deiodinases control
thyroid hormone action by activating or inactivating the precursor molecule thyroxine that is secreted by the thyroid gland.
These pathways ensure regulation of the availability of the biologically active molecule T3, which occurs in a time-and tissue-specific
fashion. In addition, because cells and plasma are in equilibrium and deiodination affects central thyroid hormone regulation,
these local deiodinase-mediated events can also affect systemic thyroid hormone economy, such as in the case of non-thyroidal
illness. Heightened interest in the field has been generated following the discovery that the deiodinases can be a component
in both the Sonic hedgehog signaling pathway and the TGR-5 signaling cascade, a G-protein-coupled receptor for bile acids.
These new mechanisms involved in deiodinase regulation indicate that local thyroid hormone activation and inactivation play
a much broader role than previously thought.
Received 29 August 2007; received after revision 11 October 2007; accepted 16 October 2007 相似文献
126.
The ability to produce differentiated cell types at will offers one approach to cell therapy and therefore the treatment and cure of degenerative diseases such as diabetes and liver failure. Until recently it was thought that differentiated cells could only be produced from embryonic or adult stem cells. However, we now know that this is not the case, and there is a growing body of evidence to show that one differentiated cell type can convert into a completely different phenotype (transdifferentiation). Understanding the cellular and molecular basis of transdifferentiation will allow us to reprogram cells for transplantation. This approach will complement the use of embryonic and adult stem cells in the treatment of degenerative disorders. In this review, we will focus on some well-documented examples of transdifferentiation. 相似文献
127.
Dolezel D Zdechovanova L Sauman I Hodkova M 《Cellular and molecular life sciences : CMLS》2008,65(6):964-969
Current models state that insect peripheral oscillators are directly responsive to light, while mammalian peripheral clock
genes are coordinated by a master clock in the brain via intermediate factors, possibly hormonal. We show that the expression
levels of two circadian clock genes, period (per) and Par Domain Protein 1 (Pdp1) in the peripheral tissue of an insect model species, the linden bug Pyrrhocoris apterus, are inversely affected by contrasting photoperiods. The effect of photoperiod on per and Pdp1 mRNA levels was found to be mediated by the corpus allatum, an endocrine gland producing juvenile hormone. Our results
provide the first experimental evidence for the effect of an endocrine gland on circadian clock gene expression in insects.
Received 31 October 2007; received after revision 7 January 2008; accepted 9 January 2008
D. Dolezel, L. Zdechovanova: These authors contributed equally to this work. 相似文献
128.
Cajal bodies (CBs) and Gems are nuclear domains that contain factors responsible for spliceosomal small nuclear ribonucleoprotein
(snRNP) biogenesis. The marker protein for CBs is coilin. In addition to snRNPs, coilin and other factors, canonical CBs contain
the survivor of motor neuron protein (SMN). SMN can also localize to Gems. Considering the important role that coilin plays
in the formation and composition of CBs, we tested the splicing efficiency of several cell lines that vary in regards to coilin
level and modification using an artificial reporter substrate. We found that cells with both hypomethylated coilin and Gems
are more efficient at reporter splicing compared to cells in which SMN localizes to CBs. In contrast, coilin reduction, which
induces Gem formation, decreases cell proliferation and artificial reporter splicing. These findings demonstrate that coilin
modifications or levels impact artificial reporter splicing, possibly by influencing snRNP biogenesis.
Received 26 December 2007; received after revision 5 February 2008; accepted 7 February 2008 相似文献
129.
130.
Richards JB Yuan X Geller F Waterworth D Bataille V Glass D Song K Waeber G Vollenweider P Aben KK Kiemeney LA Walters B Soranzo N Thorsteinsdottir U Kong A Rafnar T Deloukas P Sulem P Stefansson H Stefansson K Spector TD Mooser V 《Nature genetics》2008,40(11):1282-1284
We conducted a genome-wide association study for androgenic alopecia in 1,125 men and identified a newly associated locus at chromosome 20p11.22, confirmed in three independent cohorts (n = 1,650; OR = 1.60, P = 1.1 x 10(-14) for rs1160312). The one man in seven who harbors risk alleles at both 20p11.22 and AR (encoding the androgen receptor) has a sevenfold-increased odds of androgenic alopecia (OR = 7.12, P = 3.7 x 10(-15)). 相似文献