Dimethylation of histone H3 lysine 9 （H3K9me2） is an important epigenetic mark associated with transcription repression. Here, we identified PHF8, a JmjC-domain-containing protein, as a histone demethylase specific ...Dimethylation of histone H3 lysine 9 （H3K9me2） is an important epigenetic mark associated with transcription repression. Here, we identified PHF8, a JmjC-domain-containing protein, as a histone demethylase specific for this repressing mark. Recombinant full-length wild type protein could remove methylation from H3K9me2, but mutation of a conserved histidine to alanine H247A abolished the demethylase activity. Overexpressed exogenous PHF8 was colocalized with B23 staining. Endogenous PHF8 was also colocalized with B23 and fibrillarin, two well-established nucleolus proteins, suggesting that PHF8 is localized in the nucleolus and may regulate rRNA transcription. Indeed, PHF8 bound to the promoter region of the rDNA gene. Knockdown of PHF8 reduced the expression of rRNA, and overexpression of the gene resulted in upregulation of rRNA transcript. Concomitantly, H3K9me2 level was elevated in the promoter region of the rDNA gene in PHF8 knockdown cells and reduced significantly when the wild type but not the catalytically inactive H247A mutant PHF8 was overexpressed. Thus, our study identified a histone demethylase for H3K9me2 that regulates rRNA transcription.展开更多
In previous research on two-sided matching(TSM)decision,agents’preferences were often given in the form of exact values of ordinal numbers and linguistic phrase term sets.Nowdays,the matching agent cannot perform the...In previous research on two-sided matching(TSM)decision,agents’preferences were often given in the form of exact values of ordinal numbers and linguistic phrase term sets.Nowdays,the matching agent cannot perform the exact evaluation in the TSM situations due to the great fuzziness of human thought and the complexity of reality.Probability hesitant fuzzy sets,however,have grown in popularity due to their advantages in communicating complex information.Therefore,this paper develops a TSM decision-making approach with multi-attribute probability hesitant fuzzy sets and unknown attribute weight information.The agent attribute weight vector should be obtained by using the maximum deviation method and Hamming distance.The probabilistic hesitancy fuzzy information matrix of each agent is then arranged to determine the comprehensive evaluation of two matching agent sets.The agent satisfaction degree is calculated using the technique for order preference by similarity to ideal solution(TOPSIS).Additionally,the multi-object programming technique is used to establish a TSM method with the objective of maximizing the agent satisfaction of two-sided agents,and the matching schemes are then established by solving the built model.The study concludes by providing a real-world supply-demand scenario to illustrate the effectiveness of the proposed method.The proposed method is more flexible than prior research since it expresses evaluation information using probability hesitating fuzzy sets and can be used in scenarios when attribute weight information is unclear.展开更多
基金Acknowledgments We thank the cell biology core facility for confocal study. The PHF8 antibody was kindly provided by Dr Jiemin Wong （East China Normal University）. This work was supported by the National Basic Research Program of China （2007CB947900, 2010CB529705, 2007CB947100）, the Chinese Academy of Sci- ences （KSCX2-YW-R-04, KSCX2-YW-R-I 11）, the National Natural Science Foundation of China （30870538, 90919026）, Postdoctoral fellowship （20090460670）, and the Council of Shanghai Municipal Government for Science and Technology.
文摘Dimethylation of histone H3 lysine 9 （H3K9me2） is an important epigenetic mark associated with transcription repression. Here, we identified PHF8, a JmjC-domain-containing protein, as a histone demethylase specific for this repressing mark. Recombinant full-length wild type protein could remove methylation from H3K9me2, but mutation of a conserved histidine to alanine H247A abolished the demethylase activity. Overexpressed exogenous PHF8 was colocalized with B23 staining. Endogenous PHF8 was also colocalized with B23 and fibrillarin, two well-established nucleolus proteins, suggesting that PHF8 is localized in the nucleolus and may regulate rRNA transcription. Indeed, PHF8 bound to the promoter region of the rDNA gene. Knockdown of PHF8 reduced the expression of rRNA, and overexpression of the gene resulted in upregulation of rRNA transcript. Concomitantly, H3K9me2 level was elevated in the promoter region of the rDNA gene in PHF8 knockdown cells and reduced significantly when the wild type but not the catalytically inactive H247A mutant PHF8 was overexpressed. Thus, our study identified a histone demethylase for H3K9me2 that regulates rRNA transcription.
基金supported by the National Natural Science Foundation in China(Yue Qi,Project No.71861015).
文摘In previous research on two-sided matching(TSM)decision,agents’preferences were often given in the form of exact values of ordinal numbers and linguistic phrase term sets.Nowdays,the matching agent cannot perform the exact evaluation in the TSM situations due to the great fuzziness of human thought and the complexity of reality.Probability hesitant fuzzy sets,however,have grown in popularity due to their advantages in communicating complex information.Therefore,this paper develops a TSM decision-making approach with multi-attribute probability hesitant fuzzy sets and unknown attribute weight information.The agent attribute weight vector should be obtained by using the maximum deviation method and Hamming distance.The probabilistic hesitancy fuzzy information matrix of each agent is then arranged to determine the comprehensive evaluation of two matching agent sets.The agent satisfaction degree is calculated using the technique for order preference by similarity to ideal solution(TOPSIS).Additionally,the multi-object programming technique is used to establish a TSM method with the objective of maximizing the agent satisfaction of two-sided agents,and the matching schemes are then established by solving the built model.The study concludes by providing a real-world supply-demand scenario to illustrate the effectiveness of the proposed method.The proposed method is more flexible than prior research since it expresses evaluation information using probability hesitating fuzzy sets and can be used in scenarios when attribute weight information is unclear.
