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Key message : Forest and soil types are the main factors that influence the distribution pattern of soil organic carbon (SOC) in forests across east China. In general, SOC density was largest in north-eastern China, followed by south-eastern China, and lowest in middle-eastern China, due to regional climate and the dominant forest type (young plantations in middle-eastern China). Context : Forest SOC plays an important role in the carbon cycle in China, but large spatial heterogeneity and insufficient field observations lead to large uncertainties in the estimation of SOC. Aims : The objectives of this study were to evaluate forest SOC density in different geographic regions, forest types, and soil types and to investigate the spatial variation of SOC in forests across east China. Methods : The estimation of forest SOC was based on 348 soil profiles, which were collected from 116 forest sites in east China during 2008-2011. Results : The average SOC content was 17.5 g C kg, which leads to an average SOC density of 12.4 kg C m. The average SOC density in the organic horizon and mineral horizon was 5.47 and 6.91 kg C m, respectively, with 44.2 % SOC density dominating in the organic horizon. The average forest SOC density in north-eastern, middle-eastern, and south-eastern China was 13.5, 9.95, and 13.3 kg C m, respectively. Conclusion : SOC distribution varied among regions, forest types, and soil types in east China. The importance of influencing factors switched with depth, precipitation, and temperature dominating in the organic horizon and soil texture dominating in the mineral horizon. [ABSTRACT FROM AUTHOR]

Background: CENP-E, one of spindle checkpoint proteins, plays a crucial role in the function of spindle checkpoint. Once CENP-E expression was interrupted, the chromosomes can not separate procedurally, and may result in aneuploidy which is a hallmark of most solid cancers, such as hepatocellular carcinoma (HCC). We investigate the expression of CENP-E in human hepatocellular carcinoma,. and analyze the effect of low CENP-E expression on chromosome separation in normal liver cell line (LO2)., Methods: We determined its levels in HCC and para-cancerous tissues, human hepatocellular carcinoma-derived cell line (HepG2) and LO2 cell line using real time quantitative PCR (QPCR) and Western blot. Further to know whether reduction in CENP-E expression impairs chromosomes separation in LO2 cells. we knocked down CENP-E using shRNA expressing vector and then count the aneuploid in LO2 cells using chromosomal counts assay., Results: We found that both CENP-E mRNA and protein levels were significantly reduced in HCC tissues and HepG2 cells compared with para-cancerous tissues and LO2 cells, respectively. A significantly-increased proportion of aneuploid in these down-knocked LO2 cells compared with those treated with control shRNA vector., Conclusions: Together with other results, these results reveal that CENP-E expression was reduced in human HCC tissue, and low CENP-E expression result in aneuploidy in LO2 cells.