Searching for a common centromeric structural motif: Drosophila centromeric satellite DNAs show propensity to form telomeric-like unusual DNA structures

The molecular basis of centromere formation in a particular chromosomal reg ion is not yet understood. In higher eukaryotes, no specific DNA sequence i s required for the assembly of the kinetochore, but similar centromeric chr omatins are formed on different centromere DNA sequences. Although epigenes is has been proposed as the main mechanism for centromere specification, DN A recognition must also play a role. Through the analysis of Drosophila cen tromeric DNA sequences, we found that dodeca satellite and 18HT satellite a re able to form unusual DNA structures similar to those formed by telomeric sequences. These findings suggest the existence of a common centromeric st ructural DNA motif which we feel merits further investigation.