J C Eissenberg

..The data identify key mechanisms that control developmental homeostasis and cell fate restriction that could be manipulated to make somatic stem-cell engineering possible...

..These results support the idea that direct regulation of cohesin function underlies the diverse functions of Nipped-B and its orthologs...

..Drugs that selectively fray the ends of cancer cell chromosomes would be potent and general anti-cancer therapies. Here, I summarize data on the role of chromosome ends in cellular and organismal aging...

..In this review, our current knowledge of chromodomain structure and function is summarized...

..A number of intriguing interactions between HP1 and other proteins have been described, implicating HP1 in gene regulation, DNA replication, and nuclear architecture...

..In this review, our current knowledge of chromo domain properties is summarized and a variety of contexts in which chromo domains participate in aspects of chromatin metabolism are discussed...

..These data show that an ELL family elongation factor is essential, acts broadly in development, and is not functionally redundant to other elongation factors in vivo...

..We show that SRCAP potentiates Notch-dependent gene activation in HeLa cells. Taken together, these data implicate SRCAP and DOM in developmental gene activation...

..Binding of the RNA Polymerase II elongation factor ELL was reduced in knockdown chromosomes, suggesting that ELL is recruited to active polymerase via CTD phosphorylation...

..Immunofluorescence localization of chromosomal proteins and specific post-translational modifications of histones is a simple and rapid tool for the functional genomics of chromosomal proteins...

..Since their discovery, genetic and biochemical studies of H3K4 methylases and demethylases have provided important mechanistic insight into the role of H3K4 methylation in HOX gene regulation during development...

..This competition, together with developmental change in the stability of heterochromatin itself, decides the transcriptional state for a gene subject to heterochromatin repression...

..We also demonstrate that dELL physically interacts with Pol II. Our results strongly suggest that dELL functions with elongating RNA polymerase II in vivo...

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..Our data represent the first demonstration of an essential role for an RNA polymerase II elongation factor in the regulation of heat shock gene expression in an animal model...

..These data suggest that the silencing activity of heterochromatin is developmentally programmed...

..Here we demonstrate that the dRtf1 component of the Paf1 complex functions in Notch signaling...

..These results suggest that dynamic phosphorylation/dephosphorylation regulates HP1 activity in heterochromatic silencing...

..Together, these observations suggest that HP1 may serve as a cross-linker in chromatin, linking nucleosomal DNA and nonhistone protein complexes to form higher order chromatin structures...

..Ectopic binding of chimeric chromosomal proteins provides a useful tool for distinguishing specific protein-protein interactions from specific protein-DNA interactions important for complex assembly in vivo...

..Both of these functional domains overlap an evolutionarily conserved COOH-terminal region...

..This suggests that heterochromatin-specific proteins play a central role in the gene suppression associated with heterochromatic position effects...

..These results also show that HP1, initially recognized as a transcriptional silencer, is required for the normal transcriptional activation of heterochromatic genes...

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..The discovery of the role of elongin A in an in vivo model system defines the novel contribution played by RNA polymerase II elongation machinery in regulation of gene expression that is required for proper development...

..We propose that phosphorylation of HP1 promotes protein-protein interaction between HP1 and target binding proteins in heterochromatin...

..Ectopic expression of two of the three human HP1 family proteins significantly enhances heterochromatic silencing in Drosophila...

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..Though unpredicted by prevailing models, this mechanism is evident in other analogous systems...

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..Based on these results, we propose that Nipped-A, through the action of the SAGA and Tip60 complexes, facilitates assembly of the Notch activator complex and target gene transcription...

..ER that is unphosphorylated at both T18A and S24 is inactive. CKII activates ER by phosphorylating either T18 or S24. Further phosphorylation to produce the doubly phosphorylated protein inactivates ER...

..The implications of these observations for mechanism of heterochromatic position effects and heterochromatin function are discussed...

..These findings expand the role for RNA polymerase II elongation in targeting chromatin modifications to include a histone methyl mark more commonly associated with gene silencing...

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..Such effects of cohesin on gene expression could be responsible for many of the developmental deficits that occur in Cornelia de Lange syndrome, which is caused by mutations in the human homolog of Nipped-B...

..These studies will lead to an analysis of boundary structure, and in addition will provide clues to the mechanism(s) of gene regulation by higher order chromatin packaging...

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..We propose that heterochromatin formation is initiated at dispersed repetitive elements along the fourth chromosome and spreads for approximately 10 kb or until encountering competition from a euchromatic determinant...

..Consistent with a role in elongation, dELL knockdown reduces the levels of phosphorylated Pol II at heat-shock loci. This study implicates dELL in the expression of loci regulated by Pol II elongation...

..Our data indicate that dUTX is intimately associated with actively transcribed genes and may provide a paradigm for how H3K27 demethylation is required for the activation of preinitiated Pol II on transcriptionally poised genes...

..Biotinylation of histones was barely detectable in biotin-deprived flies, suggesting that epigenetic events might have contributed to effects of biotin deprivation...

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..We conclude that gene expression patterns and phenotypes in HCS-deficient flies in previous studies are caused by decreased biotinylation of histones rather than MCC...