Using human artificial chromosomes to study centromere assembly and function

Centromeres are the site of assembly of the kinetochore, which directs chromosome segregation during cell division. Active centromeres are characterized by the presence of nucleosomes containing CENP-A and a specific chromatin environment that resembles that of active genes. Recent work using human artificial chromosomes (HAC) sheds light on the fine balance of different histone post-translational modifications and transcription that exists at centromeres for kinetochore assembly and maintenance. Here, we review the use of HAC technology to understand centromere assembly and function. We put particular emphasis on studies using the alphoid^tetO HAC, whose centromere can be specifically modified for epigenetic engineering studies.