Recruitment of Telomerase RNP to the Telomeric Chromosome End Authored: Blackburn, EH, Seidel, J, 2006-03-09 19:41:08 GENE ONTOLOGYGO:0007004 Pubmed11017190 Pubmed11239396 Pubmed11572773 Pubmed12169735 Pubmed12589054 Pubmed15060173 Pubmed15189140 Pubmed15469829 Pubmed1585795 Pubmed16120835 Pubmed16319170 Pubmed16339074 Pubmed8413255 Reactome Database ID Release 43163096 Reactome, http://www.reactome.org ReactomeREACT_7960 Reviewed: Price, C, 2006-07-13 18:33:38 Studies in yeast and humans indicate that recruitment of telomerase to a telomere may be influenced by multiple variables, including regulatory protein factors, hTERT domains, telomere length, and the cell cycle. First, in yeast, the telomerase associated factor Est1 and the single-strand DNA binding protein Cdc13 play roles in telomerase recruitment (Pennock et al. 2001; Bianchi et al. 2004). Analogous proteins exist in human cells (Est1A, Est1B, Est1C, and POT1, respectively); however, how or whether these proteins are directly involved in telomerase recruitment remains to be elucidated. Second, N-terminal residues of hTERT within the DAT (dissociate the activities of telomerase) domain may have a role in binding single stranded telomeric DNA as the "anchor site" (Lee et al. 1993; Moriarty et al. 2005). Third, a cis-acting mechanism in yeast and humans that regulates telomere length maintenance may modulate telomerase access to the telomere (reviewed in Blackburn 2001; Smogorzewska and de Lange, 2004). Long telomeres, which have more associated protein factors, are in a state that is acted on by telomerase less frequently than that of short telomeres, which have fewer associated factors. Whether short telomeres actively recruit telomerase remains to be determined. Last, the recruitment of telomerase to telomeres shows cell-cycle regulation (Taggart et al. 2002; Smith et al. 2003; Fisher et al. 2004; Jady et al. 2006; Tomlinson et al. 2006). Further studies will be needed to determine the details of how human telomerase is recruited to a telomere. <br> Telomerase RNP Telomerase RNP Bound to the Telomeric Chromosome End