Summary• The transcription factors C-repeat binding factors/dehydration-responsive element binding proteins (CBFs/DREBs) control the expression of many stress-inducible genes in Arabidopsis.• A cDNA clone, designated GhDREB1 , was isolated from cotton ( Gossypium hirsutum ) by cDNA library screening.• Northern blot analysis indicated that mRNA accumulation of GhDREB1 was induced by low temperatures and salt stress, but was not induced by abscisic acid (ABA) or drought stress in cotton seedlings. Transgenic tobacco ( Nicotiana tabacum ) plants overexpressing GhDREB1 displayed stronger chilling tolerance than wild-type plants. Their leaf chlorophyll fluorescence, net photosynthetic rate and proline concentrations were higher than those of control plants during low-temperature treatment. However, under normal growth conditions, the transgenic tobacco plants exhibited retarded growth and delayed flowering. Interestingly, GhDREB1 transcripts in cotton seedlings were negatively regulated by gibberellic acid (GA 3 ) treatment. Analysis of the promoter of the GhDREB1 gene revealed the presence of one low-temperature and four gibberellin-responsive elements. Green fluorescent protein (GFP) signal intensity or β -glucuronidase (GUS) activity driven by the GhDREB1 promoter was clearly enhanced by low temperature but repressed by GA 3 .• These results suggest that GhDREB1 functions as a transcription factor and plays an important role in improving cold tolerance, and also affects plant growth and development via GA 3 .

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Indigenous oil-degrading bacteria play an important role in efficient remediation of polluted marine environments. In this study, we investigated the diversity and abundance of indigenous oil-degrading bacteria and functional genes in crude oil-contaminated seawater of the Dalian coast. The gene copy number bacterial 16S rRNA in total were determined to be about 10(10) copies L(-1) in contaminated seawater and 10(9) copies L(-1) in uncontaminated seawater. Bacteria of Alcanivorax, Marinobacter, Novosphingobium, Rhodococcus, and Pseudoalteromonas were found to be predominant oil-degrading bacteria in the polluted seawater in situ. In addition, bacteria belonging to Algoriphagus, Aestuariibacter, Celeribacter, Fabibacter, Zobellia, Tenacibaculum, Citreicella, Roseivirga, Winogradskyella, Thioclava, Polaribacter, and Pelagibaca were confirmed to be the first time as an oil-degrading bacterium. The indigenous functional enzymes, including AlkB or polycyclic aromatic hydrocarbons ring-hydroxylating dioxygenases α (PAH-RHDα) coding genes from Gram-positive (GP) and Gram-negative bacteria (GN), were revealed and quite diverse. About 10(10) to 10(11) copies L(-1) for the expression of alkB genes were recovered and showed that the two-thirds of all the AlkB sequences were closely related to widely distributed Alcanivorax and Marinobacter isolates. About 10(9) copies L(-1) seawater for the expression of RHDαGN genes in contaminated seawater and showed that almost all RHDαGN sequences were closely related to an uncultured bacterium; however, RHDαGP genes represented only about 10(5) copies L(-1) seawater for the expression of genes in contaminated seawater, and the naphthalene dioxygenase sequences from Rhodococcus and Mycobacterium species were most abundant. Together, their data provide evidence that there exists an active aerobic microbial community indigenous to the coastal area of the Yellow sea that is capable of degrading petroleum hydrocarbons.

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POK erythroid myeloid ontogenic factor (Pokemon), an important proto-oncoprotein, is a transcriptional repressor that regulates the expression of many genes and plays an important role in tumorigenesis. Resveratrol (RSV), a natural polyphenolic compound, has many beneficial biological effects on health. In this study, we investigated the role of Pokemon in RSV-induced biological effects and the effect of RSV on the expression of Pokemon in glioma cells. We found that overexpression of Pokemon decreased RSV-induced cell apoptosis, senescence, and anti-proliferative effects. Moreover, we showed that RSV could efficiently decrease the activity of the Pokemon promoter and the expression of Pokemon. Meanwhile, RSV also inhibited Sp1 DNA binding activity to the Pokemon promoter; whereas, it did not influence the expression and nuclear translocation of Sp1. In addition, we found that RSV could increase the recruitment of HDAC1, but decreased p300 to the Pokemon promoter. Taken together, all these results extended our understanding on the anti-cancer mechanism of RSV in glioma cells.

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Quantitative trait loci (QTLs) underlying reproductive growth stages are important for molecular breeding of soybeans [Glycine max (L.) Merr.]. Most of these QTLs identified so far derived from a single environment, and thus may be influenced by specific environmental conditions. In this study (from 2004 to 2005), analysis of QTLs underlying the period to reach a given reproductive growth stage was performed in three different environments (Harbin, Heilongjiang Province, China). QTL analysis was achieved with a recombination inbred line (RIL) population consisting of 153 lines.The RIL population derived from a cross between an American semi-dwarf cultivar (cv. Charleston) and a Chinese line with a short growth stage (cv. Dongnong 594). The growth stage data of soybean was recorded for each day. QTLs for all eight reproductive growth stages of soybean (R1 to R8) were analyzed by a composite interval mapping method combined with a mixed genetic model. Fifty-four QTLs displayed main effects and 56 QTL pairs showed epistatic effects. Two marker intervals (Satt173-Satt581, Satt402-Satt267), located on the linkage group O and D1a respectively, strongly influenced plant developmental processes during reproductive growth stages. The findings of this study open the possibility to modulate the structure of soybean growth stages by marker-assisted selection and pyramiding QTL analysis.

Marine bacterioplankton communities have profound impact on global biogeochemical cycles and ecological balances. However, relatively little is known about the bacterioplankton communities and the factors shaping their spatial distribution in subtropical island. Here, the bacterioplankton communities around a typical subtropical island, Xiamen Island, were revealed by analyzing bacterial 16S rRNA gene through quantitative PCR (qPCR) and 454 pyrosequencing methods. The qPCR results indicated that the abundance of 16S rRNA gene ranged from 2.07 × 10(7) to 2.13 × 10(8)copies mL(-1) in surface seawater among eight sampling sites (S1-S8) around Xiamen Island, and the nitrogen and phosphorus-rich sites (S5 and S8) were detected with higher 16S rRNA gene abundance. Pyrosequencing evidenced that a total of 267 genera of 47 classes in 26 different phyla (or candidate phyla) and some unclassified bacteria were obtained from seawater around Xiamen Island. The most dominant phylum was Proteobacteria (49.62-76.84% among sites), followed by Bacteroidetes (6.64-20.88%), Actinobacteria (2.58-9.20%), Firmicutes (0.03-13.30%), Verrucomicrobia (0.23-2.67%) and Planctomycetes (0.14-2.20%). Among eight sites, the nitrogen and phosphorus-rich sites (S5 and S8) exhibited higher proportions of Gammaproteobacteria, Epsilonproteobacteria, Firmicutes and lower proportions of Alphaproteobacteria and Planctomycetes than other sites. S5 and S8 also had more similar β-diversity, and sampling site near the estuary (S8) showed the highest bacterial diversity. Redundancy analysis (RDA) confirmed that total nitrogen and total phosphorus significantly (P<0.05 and P<0.01, respectively) influenced the bacterioplankton communities around Xiamen Island. These results will provide insights into bacterial abundance, diversity and distribution patterns, as well as their controlling factors, in subtropical marine ecosystems.