title: Contributions of the TEL-patch amino acid cluster on TPP1 to telomeric DNA synthesis by human telomerase.
abstract: Telomere maintenance is a highly coordinated process, and its misregulation is linked to cancer and telomere-shortening syndromes. Recent studies have shown that the TEL-patch--a cluster of amino acids on the surface of the shelterin component TPP1--is necessary for the recruitment of telomerase to the telomere in human cells. However, there has been only basic biochemical analysis of the role of TPP1 in the telomerase recruitment process. Here we develop an in vitro assay to quantitatively measure the contribution of the TEL-patch to telomerase recruitment--binding and extension of the first telomeric repeat. We also demonstrate that the TEL-patch contributes to the translocation step of the telomerase reaction. Finally, our quantitative observations indicate that the TEL-patch stabilizes the association between telomerase and telomeric DNA substrates, providing a molecular explanation for its contributions to telomerase recruitment and action.
authors.affiliation: Howard Hughes Medical Institute, Department of Chemistry and Biochemistry, BioFrontiers Institute, University of Colorado Boulder, Boulder, CO 80309, USA.
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Dalby
authors.affiliation: Chromatin Molecular Complexes, Central European Institute of Technology and Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, CZ 62500, Czech Republic. Electronic address: hofr@sci.muni.cz.
authors.forename: Ctirad
authors.initials: C
authors.lastname: Hofr
authors.affiliation: Howard Hughes Medical Institute, Department of Chemistry and Biochemistry, BioFrontiers Institute, University of Colorado Boulder, Boulder, CO 80309, USA. Electronic address: thomas.cech@colorado.edu.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Cech
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D000626:Aminopeptidases / Q000235:genetics / Q000378:metabolism*; D001667:Binding, Competitive; D004247:DNA / Q000378:metabolism*; D004261:DNA Replication; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / Q000235:genetics / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D057809:HEK293 Cells; D006801:Humans; D008958:Models, Molecular; D011485:Protein Binding; D021381:Protein Transport; D057057:Serine Proteases / Q000235:genetics / Q000378:metabolism*; D000089804:Shelterin Complex / Q000737:chemistry* / Q000378:metabolism*; D019098:Telomerase / Q000235:genetics / Q000378:metabolism*; D016615:Telomere / Q000235:genetics / Q000378:metabolism*; D034501:Telomere-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*
chemical_list: C495876:ACD protein, human; D000596:Amino Acids; D000089804:Shelterin Complex; D034501:Telomere-Binding Proteins; D004247:DNA; C509186:TERT protein, human; D019098:Telomerase; D057057:Serine Proteases; D000626:Aminopeptidases; D004152:Dipeptidyl-Peptidases and Tripeptidyl-Peptidases
keywords: DNA substrate-competition; TPP1 TEL-patch; processivity; telomerase recruitment; telomere