Chromatin immunoprecipitation cloning reveals rapid evolutionary patterns of centromeric DNA in Oryza species.
The functional centromeres of rice (Oryza sativa, AA genome) chromosomes contain two key DNA components: the CRR centromeric retrotransposons and a 155-bp satellite repeat, CentO. However, several wild Oryza species lack the CentO repeat. We developed a chromatin immunoprecipitation-based technique to clone DNA fragments derived from chromatin containing the centromeric histone H3 variant CenH3. Chromatin immunoprecipitation cloning was carried out in the CentO-less species Oryza rhizomatis (CC genome) and Oryza brachyantha (FF genome). Three previously uncharacterized genome-specific satellite repeats, CentO-C1, CentO-C2, and CentO-F, were discovered in the centromeres of these two species. An 80-bp DNA region was found to be conserved in CentO-C1, CentO, and centromeric satellite repeats from maize and pearl millet, species which diverged from rice many millions of years ago. In contrast, the CentO-F repeat shows no sequence similarity to other centromeric repeats but has almost completely replaced other centromeric sequences in O. brachyantha, including the CRR-related sequences that normally constitute a significant fraction of the centromeric DNA in grass species.
Lee
Hye-Ran
HR
Department of Horticulture, University of Wisconsin-Madison, Madison, WI 53706, USA.
Zhang
Wenli
W
Langdon
Tim
T
Jin
Weiwei
W
Yan
Huihuang
H
Cheng
Zhukuan
Z
Jiang
Jiming
J
D001483:Base Sequence; D002503:Centromere / Q000235:genetics*; D047369:Chromatin Immunoprecipitation; D003001:Cloning, Molecular; D018744:DNA, Plant / Q000235:genetics*; D019143:Evolution, Molecular; D018745:Genome, Plant; D017404:In Situ Hybridization, Fluorescence; D008969:Molecular Sequence Data; D012275:Oryza / Q000235:genetics*; D013997:Time Factors
D018744:DNA, Plant