Telomere biology and DNA repair: Enemies with benefits

This special issue features in-depth reviews of telomere biology and DNA repair. Understanding how telomeres function requires insights into the nature and regulation of the cellular pathways that detect and repair DNA lesions. As telomeres block unwarranted DNA repair reactions and avoid detection by the DNA damage signaling pathways, detailed knowledge of the earliest steps in the relevant DNA damage response pathways can point to the possible regulatory nodes where telomeres interfere with these processes. Furthermore, telomeres have co-opted some of the complexes involved in the DNA damage response, presumably to serve specific protective roles or facilitate the maintenance of the telomeric DNA. Conversely, studies of dysfunctional telomeres have shed new light on the regulation and nature of the cellular DNA damage response, illuminating specific attributes of the pathways that are not readily apparent from the analysis of genomewide DNA damage. This cross-fertilization between the two fields is reminiscent of how immunologists have furthered the understanding of pathogens and, vice versa, how virologists and microbiologists have provided insights into the host defense system. It is anticipated that efforts like this special issue will foster a continued interdisciplinary synergy between the DNA repair and telomere biology fields.