Jagannathan Group

Satellite DNA function within species and beyond

Satellite DNA are simple tandem repeats that exist at centromeric and pericentromeric regions on eukaryotic chromosomes. While the role of centromeric satellite DNA is well characterized, function(s) for the much more abundant pericentromeric satellite DNA repeats is poorly understood. Indeed, current dogma suggests that pericentromeric satellite DNA are ‘junk’ because these simple repeats possess no coding function and there is a striking lack of conservation in the primary sequence between closely related species. Arguing against the ‘junk DNA’ hypothesis, the abundance of pericentromeric satellite DNAs is remarkably stable over multiple generations, despite being prone to copy number loss and posing a significant burden on cellular resources. These observations suggest that pericentromeric satellite DNAs must serve an unappreciated function(s), which has remained undiscovered. We are currently interested in the following questions regarding pericentromeric satellite DNAs – (a) why do they exist? (b) how do they function? and (c) what is the functional significance of their divergence? More...