Histone H3 Methylation Patterns Research Articles

A Tale of Histone's Tails

The DNA of all eukaryotes is packaged into chromatin, which is composed largely of histone proteins. Covalent modifications of the tails of these proteins play an important role both in chromosome organization and in the specific regulation of individual genes. Litt et al . and Noma et al . show that methylation of Lys 4 in the amino-terminal tail of histone H3 is specific to euchromatic domains (where genes are generally active) and methylation of H3 Lys 9 is specific to heterochromatic domains of chromatin (where genes are generally inactive). Inverted repeats flanking the heterochromatin act as boundary elements and prevent its spread into the surrounding euchromatic regions. At the level of individual genes, Lo et al . show that phosphorylation of Ser 10 on histone H3 by Snf1 kinase facilitates acetylation of Lys 14 by Gcn5 (but not vice versa), and that both are needed for the activation of the INO1 gene in vivo. M. D. Litt, M. Simpson, M. Gaszner, C. D. Allis, G. Felsenfeld, Correlation between histone lysine methylation and developmental changes at the chicken β-globin locus. Science 293 , 2453-2455 (2001). [Abstract] [Full Text] K. Noma, C. D. Allis, S. I. S. Grewal, Transitions in distinct histone H3 methylation patterns at the heterochromatin domain boundaries. Science 293 , 1150-1155 (2001). [Abstract] [Full Text] W.-S. Lo, L. Duggan, N. C. Tolga Emre, R. Belotserkovskya, W. S. Lane, R. Shiekhattar, S. L. Berger, Snf1--a histone kinase that works in concert with the histone acetyltransferase Gcn5 to regulate transcription. Science 293 , 1142-1146 (2001). [Abstract] [Full Text]

A Tale of Histone's Tails

The DNA of all eukaryotes is packaged into chromatin, which is composed largely of histone proteins. Covalent modifications of the tails of these proteins play an important role in both chromosome organization and the specific regulation of individual genes (see the Review by Jenuwein and Allis ). Noma et al. show that methylation of Lys 4 in the amino-terminal tail of histone H3 is specific to euchromatic domains (where genes are generally active) and methylation of H3 Lys 9 is specific to heterochromatic domains of chromatin (where genes are generally inactive). Inverted repeats flanking the heterochromatin act as boundary elements and prevent its spread into the surrounding euchromatic regions. At the level of individual genes, Lo et al. show that phosphorylation of Ser 10 on histone H3 by Snf1 kinase facilitates acetylation of Lys 14 by Gcn5 (but not vice versa), and that both are needed for the activation of the INO1 gene in vivo. T. Jenuwein, C. D. Allis, Translating the histone code. Science 293 , 1074-1080 (2001). [Abstract] [Full Text] K-i. Noma, C. D. Allis, S. I. S. Grewal, Transitions in distinct histone H3 methylation patterns at the heterochromatin domain boundaries. Science 293 , 1150-1155 (2001). [Abstract] [Full Text] W.-S. Lo, L. Duggan, N. C. T. Emre, R. Belotserkovskya, W. S. Lane, R. Shiekhattar, S. L. Berger, Snf1--A histone kinase that works in concert with the histone acetyltransferase Gcn5 to regulate transcription. Science 293 , 1142-1146 (2001). [Abstract] [Full Text]

Transitions in distinct histone H3 methylation patterns at the heterochromatin domain boundaries.

Eukaryotic genomes are organized into discrete structural and functional chromatin domains. Here, we show that distinct site-specific histone H3 methylation patterns define euchromatic and heterochromatic chromosomal domains within a 47-kilobase region of the mating-type locus in fission yeast. H3 methylated at lysine 9 (H3 Lys9), and its interacting Swi6 protein, are strictly localized to a 20-kilobase silent heterochromatic interval. In contrast, H3 methylated at lysine 4 (H3 Lys4) is specific to the surrounding euchromatic regions. Two inverted repeats flanking the silent interval serve as boundary elements to mark the borders between heterochromatin and euchromatin. Deletions of these boundary elements lead to spreading of H3 Lys9 methylation and Swi6 into neighboring sequences. Furthermore, the H3 Lys9 methylation and corresponding heterochromatin-associated complexes prevent H3 Lys4 methylation in the silent domain.