Impacts of Maize Domestication and Breeding on Neocentromere Formation

ChIP-seq analysis of more than 25 maize inbreds with antibody recognizing the centromere-specific histone variant cenH3 revealed frequent relocation of centromeres from their original location to nearby positions. This centromere movement was observed only in domesticated maize, but not the related wild teosinte, and was accompanied by rapid invasion of the neocentromere by retrotranposons belonging to the CRM family.  Phylogenetic analysis independently confirmed that these movements occurred right around, or after, domestication in all cases, with the earliest movement dating to around 10,000 years before present.  The roles of maize domestication and breeding in this remarkable phenomenon will be discussed.