Heterochromatin Organization of a Natural Yeast Telomere

• Published in: The Journal of biological chemistry Vol. 274; no. 4; pp. 1928 - 1933
• Main Authors: Venditti, Sabrina, Vega-Palas, Miguel A., Di Mauro, Ernesto
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 22-01-1999; American Society for Biochemistry and Molecular Biology
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.274.4.1928

The chromatin organization of eukaryotic telomeres is essential for telomeric function and is currently receiving great attention. In yeast, the structural organization of telomeres involves a complex interplay of telomeric proteins that results in the formation of heterochromatin. This telomeric heterochromatin involves homotypic and heterotypic protein interactions that have been summarized in a general model.
Recent analyses have focused on the study of the structural complexity at yeast telomeres to the level of specific nucleosomes and of the distribution of protein complexes in a natural telomeric region (LIII). In this report, we further analyze the structural complexity of LIII and the implication of this structure on telomeric silencing. It is shown that the establishment of repressive heterochromatin structures at LIII requires the recruitment of Sir3p through interaction with the N terminus of histone H4. The establishment of such structures does not require acetylation of any of four lysines located in the H4 N terminus (lysines 5, 8, 12, and 16).