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41.
Ivanete de Oliveira Furo Amanda Almeida Monte Michelly da Silva dos Santos Marcella Mergulh?o Tagliarini Patricia C. M. O′Brien Malcolm A. Ferguson-Smith Edivaldo H. C. de Oliveira 《PloS one》2015,10(12)
The sunbittern (Eurypyga helias) is a South American Gruiformes, the only member of Family Eurypigidae. In most phylogenetic proposals, it is placed in a more distant position than other families of the so-called “core Gruiformes”. Different studies based on molecular, morphological and biogeographical data suggest that the Eurypigidae is closely related to the kagu (Rhynochetos jubatus), the only species in Rynochetidae, another family not included in the core Gruiformes. Here, the karyotype of the sunbittern is described for the first time, by classical and molecular cytogenetics, using whole chromosome probes derived from Gallus gallus and Leucopternis albicollis. We found a diploid number of 80, with only one pair of biarmed autosomal macrochromosomes, similar to that observed in the kagu. Chromosome painting revealed that most syntenies found in the avian putative ancestral karyotype (PAK) were conserved in the sunbittern. However, PAK1, PAK2, and PAK5 corresponded to two chromosome pairs each. Probes derived from L. albicollis confirm that fissions in PAK1 and PAK2 were centric, whereas in PAK5 the fission is interstitial. In addition, there is fusion of segments homologous to PAK2q and PAK5. From a phylogenetic point of view, comparisons of our results with two other Gruiformes belonging to family Rallidae suggest that the PAK5q fission might be a synapomorphy for Gruiformes. Fissions in PAK1 and PAK2 are found only in Eurypigidae, and might also occur in Rynochetidae, in view of the similar chromosomal morphology between the sunbittern and the kagu. This suggests a close phylogenetic relationship between Eurypigidae and Rynochetidae, whose common ancestor was separated by the Gondwana vicariancy in South America and New Caledonia, respectively. 相似文献
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Improved in Planta Expression of the Human Islet Autoantigen Glutamic Acid Decarboxylase (GAD65) 总被引:3,自引:0,他引:3
Avesani L Falorni A Tornielli GB Marusic C Porceddu A Polverari A Faleri C Calcinaro F Pezzotti M 《Transgenic research》2003,12(2):203-212
The smaller isoform of the enzyme glutamic acid decarboxylase (GAD65) is a major islet autoantigen in autoimmune type 1 diabetes mellitus (T1DM). Transgenic plants expressing human GAD65 (hGAD65) are a potential means of direct oral administration of the islet autoantigen in order to induce tolerance and prevent clinical onset of disease. We have previously reported the successful generation of transgenic tobacco and carrot that express immunoreactive, full-length hGAD65. In the present study, we tested the hypothesis that the expression levels of recombinant hGAD65 in transgenic plants can be increased by targeting the enzyme to the plant cell cytosol and by mediating expression through the potato virus X (PVX) vector. By substituting the NH2-terminal region of hGAD65 with a homologous region of rat GAD67, a chimeric GAD671-87/GAD6588-585 molecule was expressed in transgenic tobacco plants. Immunolocalization analysis showed that immunoreactive GAD67/65 was found in the plant cell cytosol. By using a radio-immuno assay with human serum from a GAD65 autoantibody-positive T1DM patient, the highest expression level of the recombinant GAD67/65 protein was estimated to be 0.19% of the total soluble protein, compared to only 0.04% of wild-type hGAD65. Transient expression of wild-type, full-length hGAD65 in N. benthamiana mediated by PVX infection was associated with expression levels of immunoreactive protein as high as 2.2% of total soluble protein. This substantial improvement of the expression of hGAD65 in plants paves the way for immunoprevention studies of oral administration of GAD65-containing transgenic plant material in animal models of spontaneous autoimmune diabetes. 相似文献
45.
Two sets of 20-mer phosphorothioate-modified oligodeoxynucleotide DNAs (sODN) and 21-mer or 22-mer small interfering RNAs (siRNAs), targeted to the same coding sites in raf-1 mRNA, were compared for their abilities to reduce the amount of endogenously expressed Raf-1 protein in T24 cells. The amount of Raf-1 protein was monitored by careful quantitation of Western blots. We found that the siRNAs were somewhat less effective than the S-ODNs in reducing the Raf-1 protein level 20 hours after a 4-hour transfection. The siRNA duplexes were characterized by circular dichroism (CD) spectra, and melting temperatures (Tm) were obtained for the siRNA duplexes and DNA x RNA hybrids formed by the S-ODNs. The S-ODNs differed in their effectiveness, the S-ODN that formed the more stable hybrid being the more effective in reducing the Raf-1 protein level, but the two siRNAs were equally effective despite a difference in Tm of about 20 degrees C. Finally, the siRNAs and S-ODNs had a comparable nonspecific effect on a nontargeted (Bcl-2) protein. Our data add to others in the literature that show it can be difficult to select siRNAs that are more effective than antisense ODNs in downregulating endogenously expressed proteins. 相似文献
46.
Medici MA Sciortino MT Perri D Amici C Avitabile E Ciotti M Balestrieri E De Smaele E Franzoso G Mastino A 《The Journal of biological chemistry》2003,278(38):36059-36067
Signals involved in protection against apoptosis by herpes simplex virus 1 (HSV-1) were investigated. Using U937 monocytoid cells as an experimental model, we have demonstrated that HSV-1 rendered these cells resistant to Fas-induced apoptosis promptly after infection. UV-inactivated virus as well as the envelope glycoprotein D (gD) of HSV-1, by itself, exerted a protective effect on Fas-induced apoptosis. NF-kappaB was activated by gD, and protection against Fas-mediated apoptosis by gD was abolished in cells stably transfected with a dominant negative mutant I-kappaBalpha, indicating that NF-kappaB activation plays a role in the antiapoptotic activity of gD in our experimental model. Moreover, NF-kappaB-dependent protection against Fas-mediated apoptosis was associated with decreased levels of caspase-8 activity and with the up-regulation of intracellular antiapoptotic proteins. 相似文献
47.
Sanna E Soro MR Calò C 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2006,64(3):333-344
The aim of this study is to evaluate the prevalence of overweight and obesity in children (6-10 years) of the city of Cagliari (Sardinia, Italy) with different socioeconomic status. The sample is composed by 1000 children, 500 males and 500 females, 6 to 10 years old, attending primary schools in Cagliari during 2003. For uniformity with similar Italian studies, in this study overweight and obesity were defined as calculated from the charts published by Tanner et al. (1966). In the Cagliari children, the prevalence of obesity is 22.70%. The percentages of overweight and obese children increase with age: respectively from 11.5% and 14.0% at 6 years to 15.4% and 22.7% at 10 years. There are higher numbers of overweight and obese boys than girls in all the age classes. Both males and females show an increasing percentage of overweight and obesity as the socioeconomic level decreases. Males present higher percentages of overweight and obesity than females of the same social level, i.e. in the lowest social category overweight is 18.68% in males and 13.60% in females and obesity 26.46% in males and 23.62% in females. The standard multivariate regression analysis with the indicator of overweight and obesity as dependent variable showed that the sex (male), socio-economic status, maternal schooling and sums of the limb and trunk skinfolds have the greatest influence on overweight and obesity. The results suggest that overweight and obesity are becoming serious social and health problems in Sardinia. 相似文献
48.
María Tereza Rojo de Almeida Carla Ríos-Luci José M. Padrón Jorge A. Palermo 《Phytochemistry》2010,71(14-15):1741-1748
Investigation of the organic extracts of the roots of Maytenus vitis-idaea and Maytenus spinosa, collected in the province of Salta, Argentina, led to isolation of eighteen compounds belonging to several classes. From M. vitis-idaea, eight methylenequinone celastroids (1–8) were isolated, four of which (4–7) were hitherto unknown. Additionally, from M. spinosa, two known celastroids, a known celastroid dimer (9), three pentacyclic triterpenoids (10–12) and six β-dihydroagarofuran sesquiterpenoid alkaloids (13–18) were identified. Compounds 4–7 were active against six solid tumor cell lines at micromolar concentrations. 相似文献
49.
Leone M Di Lello P Ohlenschläger O Pedone EM Bartolucci S Rossi M Di Blasio B Pedone C Saviano M Isernia C Fattorusso R 《Biochemistry》2004,43(20):6043-6058
No general strategy for thermostability has been yet established, because the extra stability of thermophiles appears to be the sum of different cumulative stabilizing interactions. In addition, the increase of conformational rigidity observed in many thermophilic proteins, which in some cases disappears when mesophilic and thermophilic proteins are compared at their respective physiological temperatures, suggests that evolutionary adaptation tends to maintain corresponding states with respect to conformational flexibility. In this study, we accomplished a structural analysis of the K18G/R82E Alicyclobacillus acidocaldarius thioredoxin (BacTrx) mutant, which has reduced heat resistance with respect to the thermostable wild-type. Furthermore, we have also achieved a detailed study, carried out at 25, 45, and 65 degrees C, of the backbone dynamics of both the BacTrx and its K18G/R82E mutant. Our findings clearly indicate that the insertion of the two mutations causes a loss of energetically favorable long-range interactions and renders the secondary structure elements of the double mutants more similar to those of the mesophilic Escherichia coli thioredoxin. Moreover, protein dynamics analysis shows that at room temperature the BacTrx, as well as the double mutant, are globally as rigid as the mesophilic thioredoxins; differently, at 65 degrees C, which is in the optimal growth temperature range of A. acidocaldarius, the wild-type retains its rigidity while the double mutant is characterized by a large increase of the amplitude of the internal motions. Finally, our research interestingly shows that fast motions on the pico- to nanosecond time scale are not detrimental to protein stability and provide an entropic stabilization of the native state. This study further confirms that protein thermostability is reached through diverse stabilizing interactions, which have the key role to maintain the structural folding stable and functional at the working temperature. 相似文献
50.
Rogier M. Thurlings Carla A. Wijbrandts Roelof J. Bennink Serge E. Dohmen Carlijn Voermans Diana Wouters Elena S. Izmailova Danielle M. Gerlag Berthe L. F. van Eck-Smit Paul P. Tak 《PloS one》2009,4(11)