You will be given a definition of a task first, then some input of the task.
In this task, you are given an abstract of article. Your task is to generate title for this article. Preferred titles are under thirty words.

Histone proteins play essential structural and functional roles in the transition between active and inactive chromatin states. Although histones have a high degree of conservation due to constraints to maintain the overall structure of the nucleosomal octameric core, variants have evolved to assume diverse roles in gene regulation and epigenetic silencing. Histone variants, post-translational modifications and interactions with chromatin remodeling complexes influence DNA replication, transcription, repair and recombination. The authors review recent findings on the structure of chromatin that confirm previous interparticle interactions observed in crystal structures.
Output:
Histone structure and nucleosome stability.