Interspersed centromeric element with a CENP-B box-like motif in Chironomus pallidivittatus

摘要

Short mobile elements are present in different recombined forms as interspersed GC-rich islands between AT rich centromeric 155 bp tandem repeats in the dipteran Chironomus pallidivittatus. The basic element is 80 bp long, has a pronounced invert repeat structure and contains a 17 bp segment similar to the CENP-B box in mammals. The element inserts into a specific site of the 155 bp repeat in a defined orientation surrounded by 2 bp direct repeats. The total number per genome of the main variant is 20. Elements can be present in all centromeres from C.pallidivittatus and the sibling species Chironomus tentans with pronounced differences in distribution within and between species.