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951.
Zinc finger protein5 is required for the control of trichome initiation by acting upstream of zinc finger protein8 in Arabidopsis 总被引:4,自引:0,他引:4
Arabidopsis (Arabidopsis thaliana) trichome development is a model system for studying cell development, cell differentiation, and the cell cycle. Our previous studies have shown that the GLABROUS INFLORESCENCE STEMS (GIS) family genes, GIS, GIS2, and ZINC FINGER PROTEIN8 (ZFP8), control shoot maturation and epidermal cell fate by integrating gibberellins (GAs) and cytokinin signaling in Arabidopsis. Here, we show that a new C2H2 zinc finger protein, ZFP5, plays an important role in controlling trichome cell development through GA signaling. Overexpression of ZFP5 results in the formation of ectopic trichomes on carpels and other inflorescence organs. zfp5 loss-of-function mutants exhibit a reduced number of trichomes on sepals, cauline leaves, paraclades, and main inflorescence stems in comparison with wild-type plants. More importantly, it is found that ZFP5 mediates the regulation of trichome initiation by GAs. These results are consistent with ZFP5 expression patterns and the regional influence of GA on trichome initiation. The molecular analyses suggest that ZFP5 functions upstream of GIS, GIS2, ZFP8, and the key trichome initiation regulators GLABROUS1 (GL1) and GL3. Using a steroid-inducible activation of ZFP5 and chromatin immunoprecipitation experiments, we further demonstrate that ZFP8 is the direct target of ZFP5 in controlling epidermal cell differentiation. 相似文献
952.
Gene flow from herbicide-tolerant GM rice and the heterosis of GM rice-weed F2 progeny 总被引:1,自引:0,他引:1
Chun YJ Kim DI Park KW Kim HJ Jeong SC An JH Cho KH Back K Kim HM Kim CG 《Planta》2011,233(4):807-815
Gene flow from genetically modified (GM) crops to non-GM cultivars or weedy relatives may lead to the development of more
aggressive weeds. We quantified the amount of gene flow from herbicide-tolerant GM rice (Protox GM, derived from the cultivar Dongjin) to three cultivars (Dongjin, Aranghyangchal and Hwaseong) and a weedy rice line. Gene
flow frequency generally decreased with increasing distance from the pollen donor. At the shortest distance (0.5 m), we observed
a maximum frequency (0.039%) of gene flow. We found that the cultivar Dongjin received the greatest amount of gene flow, with
the second being weedy rice. Heterosis of F2 inbred progeny was also examined between Protox GM and weedy rice. We compared growth and reproduction between F2 progeny (homozygous or hemizygous for the Protox gene) and parental rice lines (GM and weedy rice). Here, transgene-homozygous F2 progeny was significantly taller and produced
more seeds than the transgene-hemizygous F2 progeny and parental lines. Although the gene flow frequency was generally low,
our results suggest that F2 progeny between GM and weedy relatives may exhibit heterosis. 相似文献
953.
954.
The significance of BmK CT, a key chlorotoxin-like peptide isolated from the scorpion venom of Buthus martensii Karsch, is a novel blocker of the chloride ion channel and matrix metalloproteinase-2 (MMP-2). Site-directed mutagenesis
of BmK CT, wound healing assay, gelatin zymography assay and computational simulation highlight the importance of electrostatic
contribution to BmK CT–MMP-2 catalytic domain complex and a model of BmK CT–MMP-2 catalytic domain complex is therefore proposed.
This is the first documentation of the structural mechanism of in the inhibition of glioma cell migration by BmK CT and may
lead to the molecular design of specific inhibitors of MMP-2. 相似文献
955.
Yan H Sun X Sun S Wang S Zhang J Wang R An P Yang F Kang W 《International journal of biological macromolecules》2011,48(5):720-725
HPLC analysis proved that Coptis chinensis glycan contained Ara, Man, and Gal. The monosaccharide constituents of Phellodendron amurense glycan were determined by HPLC analysis. HPLC analysis proved that P. amurense glycan contained Ara, Xyl, Glu, and Gal. FT-IR spectrum of C. chinensis glycan and P. amurense glycan showed the characteristic absorption peaks of carbohydrate polymers. Exposure of the human skin to ultraviolet radiation (UVR) leads to depletion of cutaneous antioxidants, regulation of gene expression and ultimately to the development of skin diseases. In the present study, free radical scavenging activity of C. chinensis and P. amurense glycan were evaluated. The photoprotective effect of C. chinensis and P. amurense glycan against UV-induced oxidative damage was also investigated in skin. At the concentration range employed, the two glycans showed strong free radical scavenging activity. Ultraviolet radiation reduced skin antioxidant enzyme and immunity activities in animals. Administration of C. chinensis and P. amurense glycans dose-dependently significantly increased skin antioxidant enzyme and immunity activities in animals. In conclusion, C. chinensis and P. amurense glycans present photoprotective properties, which can be attributed to molecules, such as flavonoids and carotenoids, which act as UV-absorbing molecules and as antioxidants, as well as stimulate immunity activities in animals. 相似文献
956.
A novel tomato-infecting begomovirus from Guangxi province, China, was identified and characterized, for which the name Tomato leaf curl China virus (ToLCCNV) was proposed. Phylogenetic and recombination analyses of the virus genomic sequences suggested that ToLCCNV may have arisen by recombination among Tomato leaf curl Vietnam virus (ToLCVV), Tomato leaf curl Gujarat virus (ToLCGV), and an unknown virus. A betasatellite molecule was found to be associated with ToLCCNV (ToLCCNB), and its complete nucleotide sequences were determined. Infectious clones of ToLCCNV and ToLCCNB were constructed and then used for agro-inoculation of plants; ToLCCNV alone infected Nicotiana benthamiana, Nicotiana glutinosa, Petunia hybrida, and Solanum lycopersicum plants, but no symptoms were induced. ToLCCNB was required for induction of leaf curl disease in these hosts. The βC1 protein of ToLCCNB was identified as a suppressor of RNA silencing and accumulated primarily in the nucleus. Deletion mutagenesis of βC1 showed that the central part of βC1 (amino acids 44 to 74) was responsible for both the suppressor activity and nuclear localization. 相似文献
957.
Polizzi V Fazzini L Adams A Picco AM De Saeger S Van Peteghem C De Kimpe N 《Microbial ecology》2011,62(4):838-852
A Penicillium decumbens strain was collected from a water-damaged building, and the production of microbial volatile organic compounds (MVOCs) was
investigated by means of headspace solid-phase microextraction, followed by GC-MS analysis. The strain was characterized by
a high production of (+)-thujopsene. The influence of various temperatures, relative humidity (RH) values, substrates, and
inoculum concentrations on fungal growth and (+)-thujopsene production was studied. The optimal temperature and relative humidity
for P. decumbens growth were 30°C and 100% RH, respectively. In general, the more favourable the incubation parameters were for growth, the
faster maximum (+)-thujopsene production was reached. Moreover, the antifungal activity of thujopsene was tested against 16
fungal strains. The growth of five of these fungal strains was negatively affected both by thujopsene alone and when grown
in contact with the MVOCs produced by P. decumbens. Following these results and since growth of P. decumbens itself was also inhibited by thujopsene, an autoregulatory function for this compound was proposed. Few data are present
in the literature about chemical communication between fungi. The present research could, therefore, contribute to understanding
fungal metabolism and behaviour in indoor environments. 相似文献
958.
959.
An X Wang L Hou J Li G Song Y Wang J Yang M Cui Y Cao B 《Molecular biology reports》2011,38(6):4037-4043
In this study, the polymorphisms of growth hormone (GH) gene 5' promoter region and intron 8, exons 4 and 10 of growth hormone receptor (GHR) gene were analyzed in Xinong Saanen goats (SG) and Boer goats (BG). Two alleles (A and B) and three genotypes (AA, AB and BB) were detected at P1 locus of GH gene, and two alleles (G and T) and two genotypes (GG and GT) were detected at P4 locus of GHR gene by PCR-SSCP analysis. In addition, two single nucleotide polymorphisms (SNPs)-A73C (P1 locus) and G114T (P4 locus), were identified by DNA sequencing. The frequencies of alleles A and B in the two goat breeds were 0.61-0.62, and 0.39-0.38, respectively, and the frequencies of alleles G and T in the two goat breeds were 0.82-0.86, and 0.18-0.14, respectively. The SNP loci were in Hardy-Weinberg disequilibrium in both goat breeds (P<0.05). Polymorphisms of GH and GHR genes were shown to be associated with growth traits in BG breed. AA and GG genotypes were associated with superior growth traits in 1-, 2- and 3-month old individuals. Hence, AA and GG genotypes are suggested to be a molecular marker for superior growth traits in BG breed. 相似文献
960.
Sun J An Y Zhang L Chen HY Han Y Wang YJ Mao ZW Ji LN 《Journal of inorganic biochemistry》2011,105(2):149-154
In this work, the interaction between the guanine-rich single-strand oligomer AG3(T2AG3)3 quadruplex and two Ru(II) complexes, [Ru(L1)(dppz)2](PF6)4 (1) and [Ru(L2)(dppz)2](PF6)4 (2) (L1 = 5,5′-di(1-(trimethylammonio)methyl)-2,2′-dipyridyl cation, L2 = 5,5′-di(1-(triethylammonio)methyl)-2,2′-dipyridyl cation, dppz = dipyrido[3,2-a:2′,3′-c] phenazine), has been studied by UV-Visible, fluorescence, DNA melting, and circular dichroism in K+ buffer. The two complexes after binding to G-quadruplex have shown different DNA stability and fluorescence enhancement. The results show that both complexes can induce the stabilization of quadruplex DNA. ΔTm values of complexes 1 and 2 at [Ru]/[DNA] ratio of 1:1 were 9.4 and 7.0, respectively. Binding stoichiometry along with the quadruplex was investigated through a luminescence-based Job plot. The major inflection points for complexes 1 and 2 were 0.49 and 0.46, respectively. The data were consistent with the binding mode at a [quadruplex]/[complex] ratio of 1:1. In addition, the conformation of G-quadruplex was not changed by the complexes at the high ionic strength of K+ buffer. 相似文献