Biopolymers and cell. 2006; 22 (5): 323 - 338

Molecular Mechanisms of Telomerase Activity Regulation

L.V. Porubleva

Telomerase is a special ribonucleoprotein complex synthesizing telomeres which are located at the ends of linear chromosomes and are essential for maintaining chromosome stability and integrity. Telomerase is active in stem cells and almost not detected in somatic cells. Its activity is cell cycle dependent, strongly regulated during cell differentiation, and highly correlated with proliferative capacity of cells. In addition, telomerase is regulated to provide telomere length homeostasis in telomerase-positive cells of germ lines. The recent studies of global gene expression changes in telomere and telomerase mutants evidence that molecular mechanisms of telomerase regulation are very complicated, multilevel, interconnected, and highly coordinated. The aim of this review is to present current data regarding regulation of telomere synthesis by telomerase during cell cycle and differentiation as well as molecular mechanisms of telomere length homeostasis in humans and some other organisms.

Key words: telomerase, telomere, regulatory mechanisms, differentiation, cell cycle, proliferative capacity, homeostasis.