Interaction of Restin with transcription factors

The melanoma-associated antigen (MAGE) genewas first isolated from a melanoma cell in 1987. Up tonow more than 30 members of MAGE have beenidentified. These members build up a super gene fam-ily and were classified into MAGE-A, B, C, D, E, F, Gand H subfamilies by homolog analysis[1]. On the basisof tissue distribution, these antigens could be catego-rized into two groups, CT antigen (Cancer/Testis An-tigen) and non-CT antigen. The MAGE-A, B, C and Ewere considered to be the CT …     

The transfection of embryonic stem cells with Tet-on system and its responsiveness to doxycycline

Embryonic stem cells (ESCs) represent a valuable source for clinic application and basic research due to their unlimited self-renew capacity and multilineage differentiation potential. The maintenance of these characteristics is closely related with the gene expres-sion of Oct-4, mTOR, etc.[1,2]. Meanwhile, cell differ-entiation in vitro and in vivo is also related with gene expression changes, such as CyclinD, TGF-β, VEGF[3―5]. In order to study the function of interested genes, a reg…     

Identification of Contaminations Hiding Beneath the α- and β-Subunits of Partially Purified Nitrogenase MoFe Protein on the Sodium Dodecyl Sulfate Gel

To identify the unknown proteins that would contaminate the α- and β-subunits of nitrogenase MoFe protein on sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE）, the partially purified MoFe protein （Avl） preparation was obtained from Azotobacter vinelandii Lipmann OP by chroma- tography on DEAE-cellulose （DE52） and Sephacryl S-200 columns and analyzed by PAGE and matrix- assisted laser desorption/ionization time-of-flight （MALDI-TOF） mass spectrometry. The Av 1 preparation was shown to have two main bands at the position of the α- and β-subunits of crystalline Avl on the SDS gel. However, on the anoxic native PAGE, in addition to the Avl band, the preparation was shown to have three other main bands that migrated slower than Av 1. Of these three main bands, the protein with the fastest migration was identified as bacterioferritin elsewhere. The proteins on the other two bands, termed Upper and Middle, were suggested to be two different homopolymers with the same apparent subunit electrophoretic mobilities as the α- and β-subunits of Avl, respectively. By analysis of MALDI-TOF mass spectrometry, the Upper was identified as GroEL, which belongs to the heat shock protein 60 family, and the Middle was identified as glucose-6-phosphate isomerase （PGI）. In our preparation, anoxic native electrophoresis indicated that GroEL was composed of 14 identical subunits and that PGI was composed of 10 identical subunits. This is the first report of PGI, with so many subunits. The contaminating proteins in the Av 1 preparation, mainly GroEL and PGI, could be totally or partially removed from Av 1 if the shoulders and center of the elution peak were collected separately from the Sephacryl S-200 column and the center fraction was purified further by Q-Sepharose developed with an NaC1 concentration gradient. Thus, Avl with more than 90% purity was obtained. Obviously, this modified method is useful for the purification of mutant MoFe proteins with a high purity.     

Chlorophyll Fluorescence Detected Passively by Difference Reflectance Spectra of Wheat （Triticum aestivum L.） Leaf

The chlorophyll fluorescence （CF） signature emitted from vegetation provides an abundance of information regarding photosynthetics activity and has been used as a powerful tool to obtain physiological information of plant leaves in a non-invasive manner. CF is difficult to quantify because the CF signal is obscured by reflected light. In the present study, the apparent reflectance spectra of wheat （Triticum aestivum L.） leaves were measured under illuminations with and without filtering by three specially designed long-wave pass edge filters; the cut-off wavelengths of the three filters were 653.8, 678.2, and 694. l nm at 50% of maximum transmittance. The CF spectra could be derived as the reflectance difference spectra of the leaves under illuminations with and without the long wave pass edge filters. The ratio of the reflectance difference at 685 and 740 nm （Dif685/Dif740） was linear correlated with the CF parameters （maximal photochemical efficiency Fv/Fm, and the yield of quantum efficiency） measured by the modulated fluorometer. In addition, the ratio reflected the water stress status of the wheat leaf, which was very high when water deficiency was serious. This method provides a new approach for detecting CF and the physiological state of crops.     

Identification of Immunodominant Th1-type T cell Epitopes from Schistosoma japonicum 28 kDa Glutathione-S-transferase,a Vaccine Candidate

Th1-type cytokines produced by the stimulation of Th1-type epitopes derived from definedschistosome-associated antigens are correlated with the development of resistance to the parasite infection.Schistosoma mansoni 28 kDa glutathione-S-transferase(Sm28GST),a major detoxification enzyme,hasbeen recognized as a vaccine candidate and a phase Ⅱ clinical trial has been carried out.Sheep immunizedwith recombinant Schistosoma japonicum 28GST(Sj28GST)have shown immune protection against theparasite infection.In the present study,six candidate peptides(P1,P2,P3,P4,P7 and P8)from Sj28GSTwere predicted,using software,to be T cell epitopes,and peptides P5 and P6 were designed by extendingfive amino acids at the N-terminal and C-terminal of P1,respectively.The peptide 190-211 aa in Sj28GSTcorresponding to the Th1-type epitope(190-211 aa)identified from Sm28GST was selected and named P9.The nine candidate peptides were synthesized or produced as the fusion protein with thioredoxin in thepET32c(+)/BL21(DE3)system.Their capacity to induce a Th1-type response in vitro was measured usinglymphocyte proliferation,cytokine detection experiments and flow cytometry.The results showed that P6(73-86 aa)generated the strongest stimulation effect on T cells among the nine candidate peptides,and drovethe highest level of IFN-γ and IL-2.Therefore,P6 is a functional Th1-type T cell epitope that is differentfrom that in Sm28GST,and will be useful for the development of effective vaccines which can triggeracquired immunity against S.japonicum.Moreover,our strategy of identifying the Th1-type epitope by acombination of software prediction and experimental confirmation provides a convenient and cost-savingalternative approach to previous methods.     

Cloning and Expression Pattern of a Gene Encoding a Putative Plastidic ATP/ADP Transporter from Helianthus tuberosus L.

Herein, we report the cloning and molecular characterization of a full cDNA encoding a putative plastidic ATP/ADP transporter, designated HtAATP, for Helianthus tuberosus L. The ATP/ADP translocator protein was isolated from the tuber-cDNA library of H. tuberosus for the first time. The predicted HtAATP protein was judged as a plastidic ATP/ADP translocator protein from its high homology at the amino acid sequence level to the two Arabidopsis thaliana plastidic ATP/ADP translocator proteins AATP1 and AATP2 （84.8% and 79.9% identity, respectively）. Amino acid sequence analysis of the primary structure of HtAATP revealed that it belonged to the plastidic ATP/ADP transporter family. Hydropathy prediction indicated that HtAATP gene product is a highly hydrophobic membrane protein that contains 10 transmembrane domains to form a spanning topology. Southern blotting analysis showed that the HtAATP gene is a single-copy gene in the H. tuberosus genome. Tissue distribution analysis showed that the HtAATP gene is prominently expressed in sink tissues. A stable expression pattern in tubers at different developmental stages implies an active involvement of HtAATP during carbohydrate formation.     

Effect of Heavy Metals （Cd, Cu） on the Gametophytes of Laminaria japonica Aresch

Effects of various concentrations of two heavy metals, namely Cd and Cu, on gametophytes of Laminariajaponica Aresch were determined by recording morphological changes of gametophytes, determining pH values and the heavy metal content of the culture solution, calculating the germination rate of sporophytes, and observing heavy metal （Cd） distribution using a fluorescence microscope. The results showed that heavy metals damaged the gametophytes, and were even lethal, and that the higher the concentration of heavy metal ions, the greater the injury to gametophytes. Gametophytes could not survive in culture solutions containing more than 100 mg/L Cd and 50 mg/L Cu and were only able to survive in culture solution containing a mixture of Cd and Cu up to a concentration of 10 mg/L, which indicates that gametophytes have a higher tolerance to Cd than Cu and that multiple heavy metal ions in solution markedly aggravate the damage to gametophytes compared with individual heavy metal ions. With increases in the concentration of the heavy metal, the burgeoning rate of sporophytes decreased acutely, and solutions containing multiple heavy metal ions caused even more marked harm to sporophytes than solutions containing a single heavy metal ion, because most sporophytes died in mixed solutions. The pH value of the culture medium dropped immediately at the beginning （the first day） of treatment, increased over the following days, and then decreased again. The pH of culture media containing multiple heavy metal ions showed greater variation than media containing a single heavy metal ion, with the extent of the decrease in pH of culture media containing multiple ions being greatest during the last period of the experiment. With increases in the concentration of heavy metals, the capacity of gametophytes to accumulate these ions increased. The blue fluorescent light emitted by the Cd-and Cd-binding protein complex existing in gametophytes in media containing different concentrations of Cd showed clearly the distribution of the ion in gametophytes and the results obtained were consistent with distribution determined using other methods. All results of the present study showed that gametophytes of L. japonica play a remarkable role as heavy metal decontaminators, especially with regard to Cd.     

Cyclocarya cf. paliurus （Batal.） Iljinskaja （Juglandaceae） from the Hunchun Formation （Eocene）, Jilin Province, China

The leaflet architecture of Cyclocarya cf. paliurus （Batal.） Iljinskaja from the Hunchun Formation （Middle Eocene） shows similarity to that of modem C. paliurus （Batal.） Iljinskaja and the specimen is the oldest fossil record in Europe and Asia. The distributions of C. cf. paliurus and other fossil records, such as Glyptostrobus, Metasequoia, Nyssa, and Liquidambar, in Hunchun flora show that it would have been a warmer-temperature to subtropical climate in Hunchun District during the Eocene period.     

Characterization and catabolic genes analyses of oil-degrading Pseudomonas aeruginosa 1217

One oil-degrading bacterial strain 1217 isolated from oil contaminated soil could degrade crude oil. It was identified and designated as Pseudomonas aeruginosa by morphology, physiology, biochemical and 16S rDNA sequence analyses. The strain grew well at 5-65 ℃ with the initial pH of 2-10 and NaCl concentrations of 0%-9%. It grew well in the medium containing different organic substrates as sole carbon sources, such as n-dodecane, n-octadecane, benzene, toluene, xylene and naphthaline. The degrading rates for hydrocarbons were 21.57% and 15.15% when it was cultured in minimal medium containing crude oil and different chain alkanes at 30 ℃ and 10 ℃ for 7 days. The bacterium produced biosurfactants with the surface tension reduction from 72.20 mN/m to 35.14 mN/m. The oil degrading related genes such as alkane monooxygenase, toluene dioxygenase, biphenyl dioxygenase, ring hydroxylating dioxygenase and oxidoreductase genes were detected in Pseudomonas aeruginosa 1217. The alkane monooxygenase and ring hydroxylating dioxygenase genes were further cloned and analyzed. The sequence similarities of the two genes with those of Pseudomonas aeruginosa PAO1 were 99.91% and 99.22% respectively. The isolated strain exhibits great potential for the bioremediation of the hydrocarbons contaminated environments.     

Transfer of small chromosome fragments of Agropyron elongatum to wheat chromosome via asymmetric somatic hybridization

~~Transfer of small chromosome fragments of Agropyron elongatum to wheat chromosome via asymmetric somatic hybridization1 .Dong,Y.C,GenePools of common wheat,Journal of Triticeae CroPs(in Chinese),2000,20(3):78-81. 2 .Wei,Y.M.,Zheng,YL.Zhou,R.H., Detectlon of the rye chro- matin in multisPikelet wheat germplasm 10-A background using fluorescence in situ hybridization(FISH)and RFLP markers,Acta Bot.Sinica(in Chinese),1999,41(7):722-725. 3 .Xiang,E N.,Xia,G M.…