Non-telomeric chromosome localisation of (TTAGGG)n in the genus Eulemur

The chromosomal distribution of the (TTAGGG)n telomeric repetitive sequences was studied in the Malagasy species Eulemur fulvus fulvus (2n = 60), Eulemur rubriventer (2n = 50), Eulemur coronatus (2n = 46) and Eulemur macaco (2n = 44). These sequences hybridize to the telomeres of all chromosomes of the four species and also to the pericentromeres of all chromosomes of E. fulvus, E. coronatus and E. macaco, with the exception of the pericentromeres of E. coronatus and E. macaco chromosomes 9, the homeologous E. fulvus chromosomes 2 and E. macaco chromosomes 1. In E. rubriventer only a very weak signal was detected at the pericentromeres of a few chromosomes. In E. fulvus, E. coronatus and E. macaco, non-telomeric (TTAGGG)n sequences collocalize with constitutive heterochromatin. The interspecific differences of the hybridization pattern of (TTAGGG)n sequences at the pericentromeres suggest that E. rubriventer branched off the common trunk before amplification of endogenous (TTAGGG)n sequences occurred in pericentromeric regions.