|
|
Line 4: |
Line 4: |
| == Structural highlights == | | == Structural highlights == |
| <table><tr><td colspan='2'>[[7uy5]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Tetrahymena_thermophila Tetrahymena thermophila]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7UY5 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7UY5 FirstGlance]. <br> | | <table><tr><td colspan='2'>[[7uy5]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Tetrahymena_thermophila Tetrahymena thermophila]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7UY5 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7UY5 FirstGlance]. <br> |
- | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.5Å</td></tr> |
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr> |
| <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=7uy5 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7uy5 OCA], [https://pdbe.org/7uy5 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7uy5 RCSB], [https://www.ebi.ac.uk/pdbsum/7uy5 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7uy5 ProSAT]</span></td></tr> | | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=7uy5 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7uy5 OCA], [https://pdbe.org/7uy5 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7uy5 RCSB], [https://www.ebi.ac.uk/pdbsum/7uy5 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7uy5 ProSAT]</span></td></tr> |
| </table> | | </table> |
| == Function == | | == Function == |
- | [[https://www.uniprot.org/uniprot/LARP7_TETTS LARP7_TETTS]] RNA-binding protein required for assembly of the holoenzyme telomerase ribonucleoprotein (RNP) complex (PubMed:15131081, PubMed:15696174, PubMed:16507983, PubMed:17322903, PubMed:20713447, PubMed:22315458, PubMed:22705372). Telomerase is an essential ribonucleoprotein enzyme that copies new telomeric repeats onto chromosome ends by repetitively synthesizing the short telomere-repeat sequence 5'-TTGGGG-3' using an RNA template component TER (PubMed:15696174, PubMed:17322903, PubMed:20713447). TAP65/p65 specifically binds telomerase RNA template TER and is required for biogenesis and placement of the TER stem-terminus element: TAP65/p65 first protects the 3'-end of TER from degradation and acts as a chaperone to correctly fold TER for protein binding; it then bends TER stem-loop IV to position it for interaction of stem-loop IV with catalytic TERT RNA-binding domain (PubMed:15696174, PubMed:17322903, PubMed:20713447, PubMed:22315458, PubMed:22705372).<ref>PMID:15131081</ref> <ref>PMID:15696174</ref> <ref>PMID:16507983</ref> <ref>PMID:17322903</ref> <ref>PMID:20713447</ref> <ref>PMID:22315458</ref> <ref>PMID:22705372</ref>
| + | [https://www.uniprot.org/uniprot/LARP7_TETTS LARP7_TETTS] RNA-binding protein required for assembly of the holoenzyme telomerase ribonucleoprotein (RNP) complex (PubMed:15131081, PubMed:15696174, PubMed:16507983, PubMed:17322903, PubMed:20713447, PubMed:22315458, PubMed:22705372). Telomerase is an essential ribonucleoprotein enzyme that copies new telomeric repeats onto chromosome ends by repetitively synthesizing the short telomere-repeat sequence 5'-TTGGGG-3' using an RNA template component TER (PubMed:15696174, PubMed:17322903, PubMed:20713447). TAP65/p65 specifically binds telomerase RNA template TER and is required for biogenesis and placement of the TER stem-terminus element: TAP65/p65 first protects the 3'-end of TER from degradation and acts as a chaperone to correctly fold TER for protein binding; it then bends TER stem-loop IV to position it for interaction of stem-loop IV with catalytic TERT RNA-binding domain (PubMed:15696174, PubMed:17322903, PubMed:20713447, PubMed:22315458, PubMed:22705372).<ref>PMID:15131081</ref> <ref>PMID:15696174</ref> <ref>PMID:16507983</ref> <ref>PMID:17322903</ref> <ref>PMID:20713447</ref> <ref>PMID:22315458</ref> <ref>PMID:22705372</ref> |
- | <div style="background-color:#fffaf0;">
| + | |
- | == Publication Abstract from PubMed ==
| + | |
- | Telomeres are the physical ends of linear chromosomes. They are composed of short repeating sequences (such as TTGGGG in the G-strand for Tetrahymena thermophila) of double-stranded DNA with a single-strand 3' overhang of the G-strand and, in humans, the six shelterin proteins: TPP1, POT1, TRF1, TRF2, RAP1 and TIN2(1,2). TPP1 and POT1 associate with the 3' overhang, with POT1 binding the G-strand(3) and TPP1 (in complex with TIN2(4)) recruiting telomerase via interaction with telomerase reverse transcriptase(5) (TERT). The telomere DNA ends are replicated and maintained by telomerase(6), for the G-strand, and subsequently DNA polymerase alpha-primase(7,8) (PolalphaPrim), for the C-strand(9). PolalphaPrim activity is stimulated by the heterotrimeric complex CTC1-STN1-TEN1(10-12) (CST), but the structural basis of the recruitment of PolalphaPrim and CST to telomere ends remains unknown. Here we report cryo-electron microscopy (cryo-EM) structures of Tetrahymena CST in the context of the telomerase holoenzyme, in both the absence and the presence of PolalphaPrim, and of PolalphaPrim alone. Tetrahymena Ctc1 binds telomerase subunit p50, a TPP1 orthologue, on a flexible Ctc1 binding motif revealed by cryo-EM and NMR spectroscopy. The PolalphaPrim polymerase subunit POLA1 binds Ctc1 and Stn1, and its interface with Ctc1 forms an entry port for G-strand DNA to the POLA1 active site. We thus provide a snapshot of four key components that are required for telomeric DNA synthesis in a single active complex-telomerase-core ribonucleoprotein, p50, CST and PolalphaPrim-that provides insights into the recruitment of CST and PolalphaPrim and the handoff between G-strand and C-strand synthesis.
| + | |
| | | |
- | Structure of Tetrahymena telomerase-bound CST with polymerase alpha-primase.,He Y, Song H, Chan H, Liu B, Wang Y, Susac L, Zhou ZH, Feigon J Nature. 2022 Aug;608(7924):813-818. doi: 10.1038/s41586-022-04931-7. Epub 2022, Jul 13. PMID:35831498<ref>PMID:35831498</ref>
| + | ==See Also== |
- | | + | *[[Telomerase 3D structures|Telomerase 3D structures]] |
- | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
| + | |
- | </div>
| + | |
- | <div class="pdbe-citations 7uy5" style="background-color:#fffaf0;"></div>
| + | |
| == References == | | == References == |
| <references/> | | <references/> |
| Structural highlights
Function
LARP7_TETTS RNA-binding protein required for assembly of the holoenzyme telomerase ribonucleoprotein (RNP) complex (PubMed:15131081, PubMed:15696174, PubMed:16507983, PubMed:17322903, PubMed:20713447, PubMed:22315458, PubMed:22705372). Telomerase is an essential ribonucleoprotein enzyme that copies new telomeric repeats onto chromosome ends by repetitively synthesizing the short telomere-repeat sequence 5'-TTGGGG-3' using an RNA template component TER (PubMed:15696174, PubMed:17322903, PubMed:20713447). TAP65/p65 specifically binds telomerase RNA template TER and is required for biogenesis and placement of the TER stem-terminus element: TAP65/p65 first protects the 3'-end of TER from degradation and acts as a chaperone to correctly fold TER for protein binding; it then bends TER stem-loop IV to position it for interaction of stem-loop IV with catalytic TERT RNA-binding domain (PubMed:15696174, PubMed:17322903, PubMed:20713447, PubMed:22315458, PubMed:22705372).[1] [2] [3] [4] [5] [6] [7]
See Also
References
- ↑ Witkin KL, Collins K. Holoenzyme proteins required for the physiological assembly and activity of telomerase. Genes Dev. 2004 May 15;18(10):1107-18. doi: 10.1101/gad.1201704. Epub 2004 May 6. PMID:15131081 doi:http://dx.doi.org/10.1101/gad.1201704
- ↑ Prathapam R, Witkin KL, O'Connor CM, Collins K. A telomerase holoenzyme protein enhances telomerase RNA assembly with telomerase reverse transcriptase. Nat Struct Mol Biol. 2005 Mar;12(3):252-7. doi: 10.1038/nsmb900. Epub 2005 Feb 6. PMID:15696174 doi:http://dx.doi.org/10.1038/nsmb900
- ↑ O'Connor CM, Collins K. A novel RNA binding domain in tetrahymena telomerase p65 initiates hierarchical assembly of telomerase holoenzyme. Mol Cell Biol. 2006 Mar;26(6):2029-36. doi: 10.1128/MCB.26.6.2029-2036.2006. PMID:16507983 doi:http://dx.doi.org/10.1128/MCB.26.6.2029-2036.2006
- ↑ Stone MD, Mihalusova M, O'connor CM, Prathapam R, Collins K, Zhuang X. Stepwise protein-mediated RNA folding directs assembly of telomerase ribonucleoprotein. Nature. 2007 Mar 22;446(7134):458-61. doi: 10.1038/nature05600. Epub 2007 Feb 25. PMID:17322903 doi:http://dx.doi.org/10.1038/nature05600
- ↑ Berman AJ, Gooding AR, Cech TR. Tetrahymena telomerase protein p65 induces conformational changes throughout telomerase RNA (TER) and rescues telomerase reverse transcriptase and TER assembly mutants. Mol Cell Biol. 2010 Oct;30(20):4965-76. doi: 10.1128/MCB.00827-10. Epub 2010 Aug , 16. PMID:20713447 doi:http://dx.doi.org/10.1128/MCB.00827-10
- ↑ Akiyama BM, Loper J, Najarro K, Stone MD. The C-terminal domain of Tetrahymena thermophila telomerase holoenzyme protein p65 induces multiple structural changes in telomerase RNA. RNA. 2012 Apr;18(4):653-60. doi: 10.1261/rna.031377.111. Epub 2012 Feb 7. PMID:22315458 doi:http://dx.doi.org/10.1261/rna.031377.111
- ↑ Singh M, Wang Z, Koo BK, Patel A, Cascio D, Collins K, Feigon J. Structural Basis for Telomerase RNA Recognition and RNP Assembly by the Holoenzyme La Family Protein p65. Mol Cell. 2012 Jun 14. PMID:22705372 doi:10.1016/j.molcel.2012.05.018
|