Regulation of histone H2A and H2B ubiquitylation.

Histone ubiquitylation has emerged as an important chromatin modification with roles in transcription and trans-histone methylation. In the past several years, there has been dramatic progress in the identification of factors that control ubiquitin attachment to the core histones H2A and H2B. Recent advances in this area will be reviewed, and outstanding questions relating to the cellular functions of these modified histones will be discussed.