In vitro Dimerization of Telomerase Protein Est3p is Stimulated by Magnesium Cations

Telomeres are the special DNA protein structures at the end of the linear chromosomes of eukaryotic organisms. Telomeres maintain chromosome stability, protect them from degradation and fusion, participate in the regulation of transcription of genes in the subte lomeric regions and play an important role in cell aging [1]. Telomere DNA consists of repeated nucle otide sequences (telomeric repeats) and has a 3' pro truding single strand end. Each cell division results in under replication and telomere shortening. At a cer tain critical length of telomeres, cells can not divide and enter senescence and finally dies. However in most of the cells with unlimited division potential, such as unicellular organisms or germinal, stem or tumor cells, the telomeres are maintained by telom erase, which contain telomerase RNA, reverse tran scriptase and some other proteins [1].