The role of histone N-terminal domains on the thermodynamic stability of nucleosomes assembled on several different telomeric DNAs as well as on 'average' sequence DNA and on strong nucleosome positioning sequences, has been studied by competitive reconstitution. We find that histone tails hyperacetylation favors nucleosome formation, in a similar extent for all the examined sequences. On the contrary, removal of histone terminal domains by selective trypsinization causes a decrease of nucleosome stability which is smaller for telomeres compared to the other sequences examined, suggesting that telomeric sequences have only minor interactions with histone tails. Micrococcal nuclease kinetics shows enhanced accessibility of acetylated nucleosomes formed both on telomeric and 'average' sequence DNAs. These results suggest a more complex role for histone acetylation than the decrease of electrostatic interactions between DNA and histones. (C) 2003 Elsevier Science B.V. All rights reserved.
Acetylated nucleosome assembly on telomeric DNAs / Cacchione, Stefano; J. L., Rodriguez; Mechelli, Rosella; L., Franco; Savino, Maria. - In: BIOPHYSICAL CHEMISTRY. - ISSN 0301-4622. - STAMPA. - 104:2(2003), pp. 381-392. [10.1016/s0301-4622(03)00028-0]
Acetylated nucleosome assembly on telomeric DNAs
CACCHIONE, Stefano;MECHELLI, Rosella;SAVINO, Maria
2003
Abstract
The role of histone N-terminal domains on the thermodynamic stability of nucleosomes assembled on several different telomeric DNAs as well as on 'average' sequence DNA and on strong nucleosome positioning sequences, has been studied by competitive reconstitution. We find that histone tails hyperacetylation favors nucleosome formation, in a similar extent for all the examined sequences. On the contrary, removal of histone terminal domains by selective trypsinization causes a decrease of nucleosome stability which is smaller for telomeres compared to the other sequences examined, suggesting that telomeric sequences have only minor interactions with histone tails. Micrococcal nuclease kinetics shows enhanced accessibility of acetylated nucleosomes formed both on telomeric and 'average' sequence DNAs. These results suggest a more complex role for histone acetylation than the decrease of electrostatic interactions between DNA and histones. (C) 2003 Elsevier Science B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
