A hitchhiker's guide to survival finally makes CENs

Most strains of the yeast Saccharomyces cerevisiae contain many copies of a 2-microm plasmid, a selfish autonomously replicating DNA that relies on two different mechanisms to ensure its survival. One of these mechanisms involves the high fidelity segregation of the plasmids to daughter cells during cell division, a property that is starkly reminiscent of centromeres. A new study reported in this issue (see Hajra et al. on p. 779) demonstrates that this high fidelity is achieved by the 2-microm plasmid, effectively recruiting the centromeric histone Cse4 from its host yeast cell to forge its own centromere and finally revealing how the 2-microm plasmid has survived in budding yeasts over millions of years.