PathwayStep4729 PathwayStep4730 PathwayStep4732 PathwayStep4731 PathwayStep4734 PathwayStep4733 PathwayStep4735 Biogenesis And Assembly Of The Telomerase RNP Recruitment of Telomerase RNP to the Telomeric Chromosome End Alignment Of The RNA Template On The Telomeric Chromosome End Elongation Of The Telomeric Chromosome End Translocation Of Telomerase RNP And Alignment Of RNA Template (TERC) To Extended Single Stranded Telomeric Chromosome-End Elongation of Extended Telomeric Chromosome End Disassociation of Telomerase RNP and the Chromosome End Telomere Extension By Telomerase Authored: Blackburn, EH, Seidel, J, 2006-03-09 19:41:08 GENE ONTOLOGYGO:0007004 Humans, like most eukaryotic organisms, add direct repeats to the telomere using a specialized DNA polymerase called telomerase. Telomerase is a ribonucleoprotein (RNP) complex minimally composed of a conserved protein subunit containing a reverse transcriptase domain (human telomerase reverse transcriptase, hTERT) and a template-containing RNA (human telomerase RNA component, hTERC, or hTR, hTER). The primer for telomerase is the G-rich single-strand overhang at the chromosome end. <br><br><br>Telomerase can perform multiple rounds of repeat synthesis. The reaction cycle has been inferred from in vitro studies of telomerase from multiple organisms and can be described as having four events: 1) DNA primer recognition, 2) RNA template alignment, 3) elongation, and 4) translocation. Telomeric DNA is recognized in part by a presumed "anchor site" in hTERT, which preferentially binds G-rich DNA, and this interaction can affect elongation and translocation steps. This interaction occurs 5' of the alignment of the RNA template with the end nucleotides of the chromosome. RNA alignment positions the template adjacent to the chromosome terminus. During elongation, the template directs sequential addition of nucleotides to the telomere end. After synthesis of a repeat is completed, relative movement of telomerase and the primer, termed translocation, repositions telomerase at the end of the newly added sequence to allow initiation of another round of repeat addition. <br> Pubmed14685173 Pubmed15189140 Reactome Database ID Release 43171319 Reactome, http://www.reactome.org ReactomeREACT_7974 Reviewed: Price, C, 2006-07-13 18:33:38