RT Journal Article SR Electronic T1 Genetic Definition and Sequence Analysis of Arabidopsis Centromeres JF Science JO Science FD American Association for the Advancement of Science SP 2468 OP 2474 DO 10.1126/science.286.5449.2468 VO 286 IS 5449 A1 Copenhaver, Gregory P. A1 Nickel, Kathryn A1 Kuromori, Takashi A1 Benito, Maria-Ines A1 Kaul, Samir A1 Lin, Xiaoying A1 Bevan, Michael A1 Murphy, George A1 Harris, Barbara A1 Parnell, Laurence D. A1 McCombie, W. Richard A1 Martienssen, Robert A. A1 Marra, Marco A1 Preuss, Daphne YR 1999 UL http://science.sciencemag.org/content/286/5449/2468.abstract AB High-precision genetic mapping was used to define the regions that contain centromere functions on each natural chromosome inArabidopsis thaliana. These regions exhibited dramatic recombinational repression and contained complex DNA surrounding large arrays of 180–base pair repeats. Unexpectedly, the DNA within the centromeres was not merely structural but also encoded several expressed genes. The regions flanking the centromeres were densely populated by repetitive elements yet experienced normal levels of recombination. The genetically defined centromeres were well conserved among Arabidopsis ecotypes but displayed limited sequence homology between different chromosomes, excluding repetitive DNA. This investigation provides a platform for dissecting the role of individual sequences in centromeres in higher eukaryotes.