Isolation of a species-specific satellite DNA with a novel CENP-B-like boxfrom the North African rodent Lemniscomys barbarus

A species-specific satellite DNA (Lb-MspISAT) was isolated from the North A frican rodent Lemniscomys barbarus. This DNA is highly homogeneous in the s equence of different repeats and shows no internal repetitions. Filter and in situ hybridizations demonstrated that it is tandemly repeated at the cen tromeres of all chromosomes of the complement. A 19-bp CENP-B-like motif wa s found in Lb-MspISAT which conserves 12 of the 17-bp of the human CENP-B b ox, but only 5 of the 9-bp of the canonical sequence that is necessary to b ind the CENP-B protein. Compared with the human CENP-B box, nucleotide subs titutions and insertions increase the palindromic structure of this motif. The possibilities that it may be involved in centromeric function or in hom ogenization of the Lb-MspISAT sequence are discussed. (C)1999 Academic Pres s.