Human telomerase contains two cooperating telomerase RNA molecules.
Telomerase uses a short stretch of its intrinsic RNA molecule as template for telomere repeat synthesis. Reverse transcription of the RNA template is catalyzed by the telomerase reverse transcriptase (TERT) protein subunit. We demonstrate that human telomerase reconstituted from recombinant TERT and telomerase RNA runs as a dimer on a gel filtration column and that it contains two telomerase RNA molecules. Significantly, a telomerase heterodimer reconstituted from wild-type and mutant telomerase RNA is barely active when compared with the wild-type homodimer. We conclude that the telomerase RNA templates in the active enzyme are interdependent and functionally cooperate with each other. We discuss models that may explain the biological and enzymatic roles of telomerase dimerization.
Wenz
C
C
Swiss Institute for Experimental Cancer Research, CH-1066 Epalinges, Switzerland.
Enenkel
B
B
Amacker
M
M
Kelleher
C
C
Damm
K
K
Lingner
J
J
D001483:Base Sequence; D020134:Catalytic Domain; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D017931:DNA Primers; D004268:DNA-Binding Proteins; D006801:Humans; D007700:Kinetics; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames; D011487:Protein Conformation; D012313:RNA / Q000737:chemistry / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D019098:Telomerase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D013698:Templates, Genetic; D014158:Transcription, Genetic
D017931:DNA Primers; D004268:DNA-Binding Proteins; D011994:Recombinant Proteins; C422952:telomerase RNA; D012313:RNA; C509186:TERT protein, human; D019098:Telomerase