In the nucleus of a cell, DNA is tightly packaged into chromatin and chromosomes by aid of histone proteins. When a cell divides, each chromosome must be replicated and properly segregated into daughter nuclei. A specific region on every chromosomes, the centromere, aids in this separation of chromosomes. Our lab uses genetics, molecular biology and cell biology tools to study the DNA and proteins that form centromeres. Centromere-binding proteins play critical roles in directing mechanical forces that help separate chromosomes, mostly generated by molecular motors. Our recent studies show that eukaryotes make use of different strategies to maintain centromeres and suggest a model in which centromere proteins nucleate at the centromeric DNA core region but require two specific proteins involved in epigenetic regulation, DIM-5 and HP1, for spreading and maintenance of a normal centromere.http://biochem.science.oregonstate.edu/people/michael-freitag