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Logeswaran D, Li Y, Akhter K, Podlevsky JD, Olson TL, Forsberg K, Chen JJL. Biogenesis of telomerase RNA from a protein-coding mRNA precursor. Proc Natl Acad Sci U S A 2022; 119:e2204636119. [PMID: 36197996 PMCID: PMC9564094 DOI: 10.1073/pnas.2204636119] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 08/29/2022] [Indexed: 11/19/2022] Open
Abstract
Telomerase is a eukaryotic ribonucleoprotein (RNP) enzyme that adds DNA repeats onto chromosome ends to maintain genomic stability and confer cellular immortality in cancer and stem cells. The telomerase RNA (TER) component is essential for telomerase catalytic activity and provides the template for telomeric DNA synthesis. The biogenesis of TERs is extremely divergent across eukaryotic kingdoms, employing distinct types of transcription machinery and processing pathways. In ciliates and plants, TERs are transcribed by RNA polymerase III (Pol III), while animal and ascomycete fungal TERs are transcribed by RNA Pol II and share biogenesis pathways with small nucleolar RNA (snoRNA) and small nuclear RNA (snRNA), respectively. Here, we report an unprecedented messenger RNA (mRNA)-derived biogenesis pathway for the 1,291 nucleotide TER from the basidiomycete fungus Ustilago maydis. The U. maydis TER (UmTER) contains a 5'-monophosphate, distinct from the 5' 2,2,7-trimethylguanosine (TMG) cap common to animal and ascomycete fungal TERs. The mature UmTER is processed from the 3'-untranslated region (3'-UTR) of a larger RNA precursor that possesses characteristics of mRNA including a 5' 7-methyl-guanosine (m7G) cap, alternative splicing of introns, and a poly(A) tail. Moreover, this mRNA transcript encodes a protein called Early meiotic induction protein 1 (Emi1) that is conserved across dikaryotic fungi. A recombinant UmTER precursor expressed from an mRNA promoter is processed correctly to yield mature UmTER, confirming an mRNA-processing pathway for producing TER. Our findings expand the plethora of TER biogenesis mechanisms and demonstrate a pathway for producing a functional long noncoding RNA from a protein-coding mRNA precursor.
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Affiliation(s)
| | - Yang Li
- School of Molecular Sciences, Arizona State University, Tempe, AZ 85281
| | - Khadiza Akhter
- School of Molecular Sciences, Arizona State University, Tempe, AZ 85281
| | | | - Tamara L. Olson
- School of Molecular Sciences, Arizona State University, Tempe, AZ 85281
| | | | - Julian J.-L. Chen
- School of Molecular Sciences, Arizona State University, Tempe, AZ 85281
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Logeswaran D, Li Y, Podlevsky JD, Chen JJL. Monophyletic Origin and Divergent Evolution of Animal Telomerase RNA. Mol Biol Evol 2021; 38:215-228. [PMID: 32770221 PMCID: PMC8480181 DOI: 10.1093/molbev/msaa203] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Telomerase RNA (TR) is a noncoding RNA essential for the function of telomerase ribonucleoprotein. TRs from vertebrates, fungi, ciliates, and plants exhibit extreme diversity in size, sequence, secondary structure, and biogenesis pathway. However, the evolutionary pathways leading to such unusual diversity among eukaryotic kingdoms remain elusive. Within the metazoan kingdom, the study of TR has been limited to vertebrates and echinoderms. To understand the origin and evolution of TR across the animal kingdom, we employed a phylogeny-guided, structure-based bioinformatics approach to identify 82 novel TRs from eight previously unexplored metazoan phyla, including the basal-branching sponges. Synthetic TRs from two representative species, a hemichordate and a mollusk, reconstitute active telomerase in vitro with their corresponding telomerase reverse transcriptase components, confirming that they are authentic TRs. Comparative analysis shows that three functional domains, template-pseudoknot (T-PK), CR4/5, and box H/ACA, are conserved between vertebrate and the basal metazoan lineages, indicating a monophyletic origin of the animal TRs with a snoRNA-related biogenesis mechanism. Nonetheless, TRs along separate animal lineages evolved with divergent structural elements in the T-PK and CR4/5 domains. For example, TRs from echinoderms and protostomes lack the canonical CR4/5 and have independently evolved functionally equivalent domains with different secondary structures. In the T-PK domain, a P1.1 stem common in most metazoan clades defines the template boundary, which is replaced by a P1-defined boundary in vertebrates. This study provides unprecedented insight into the divergent evolution of detailed TR secondary structures across broad metazoan lineages, revealing ancestral and later-diversified elements.
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Affiliation(s)
| | - Yang Li
- School of Molecular Sciences, Arizona State University, Tempe, AZ
| | | | - Julian J-L Chen
- School of Molecular Sciences, Arizona State University, Tempe, AZ
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Waldl M, Thiel BC, Ochsenreiter R, Holzenleiter A, de Araujo Oliveira JV, Walter MEMT, Wolfinger MT, Stadler PF. TERribly Difficult: Searching for Telomerase RNAs in Saccharomycetes. Genes (Basel) 2018; 9:genes9080372. [PMID: 30049970 PMCID: PMC6115765 DOI: 10.3390/genes9080372] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 07/17/2018] [Accepted: 07/18/2018] [Indexed: 11/20/2022] Open
Abstract
The telomerase RNA in yeasts is large, usually >1000 nt, and contains functional elements that have been extensively studied experimentally in several disparate species. Nevertheless, they are very difficult to detect by homology-based methods and so far have escaped annotation in the majority of the genomes of Saccharomycotina. This is a consequence of sequences that evolve rapidly at nucleotide level, are subject to large variations in size, and are highly plastic with respect to their secondary structures. Here, we report on a survey that was aimed at closing this gap in RNA annotation. Despite considerable efforts and the combination of a variety of different methods, it was only partially successful. While 27 new telomerase RNAs were identified, we had to restrict our efforts to the subgroup Saccharomycetacea because even this narrow subgroup was diverse enough to require different search models for different phylogenetic subgroups. More distant branches of the Saccharomycotina remain without annotated telomerase RNA.
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Affiliation(s)
- Maria Waldl
- Institute for Theoretical Chemistry, University of Vienna, Währingerstraße 17, A-1090 Wien, Austria.
| | - Bernhard C Thiel
- Institute for Theoretical Chemistry, University of Vienna, Währingerstraße 17, A-1090 Wien, Austria.
| | - Roman Ochsenreiter
- Institute for Theoretical Chemistry, University of Vienna, Währingerstraße 17, A-1090 Wien, Austria.
| | - Alexander Holzenleiter
- BioInformatics Group, Fakultät CB Hochschule Mittweida, Technikumplatz 17, D-09648 Mittweida, Germany.
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University of Leipzig, Härtelstraße 16-18, D-04107 Leipzig, Germany.
| | - João Victor de Araujo Oliveira
- Departamento de Ciência da Computação, Instituto de Ciências Exatas, Universidade de Brasília, Campus Universitário⁻Asa Norte, Brasília, DF CEP: 70910-900, Brazil.
| | - Maria Emília M T Walter
- Departamento de Ciência da Computação, Instituto de Ciências Exatas, Universidade de Brasília, Campus Universitário⁻Asa Norte, Brasília, DF CEP: 70910-900, Brazil.
| | - Michael T Wolfinger
- Institute for Theoretical Chemistry, University of Vienna, Währingerstraße 17, A-1090 Wien, Austria.
- Center for Anatomy and Cell Biology, Medical University of Vienna, Währingerstraße 13, 1090 Vienna, Austria.
| | - Peter F Stadler
- Institute for Theoretical Chemistry, University of Vienna, Währingerstraße 17, A-1090 Wien, Austria.
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Competence Center for Scalable Data Services and Solutions, and Leipzig Research Center for Civilization Diseases, Universität Leipzig, D-04107 Leipzig, Germany.
- Max Planck Institute for Mathematics in the Sciences, Inselstraße 22, D-04103 Leipzig, Germany.
- Santa Fe Institute, 1399 Hyde Park Rd., Santa Fe, NM 87501, USA.
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Abstract
Telomerase is the eukaryotic solution to the ‘end-replication problem’ of linear chromosomes by synthesising the highly repetitive DNA constituent of telomeres, the nucleoprotein cap that protects chromosome termini. Functioning as a ribonucleoprotein (RNP) enzyme, telomerase is minimally composed of the highly conserved catalytic telomerase reverse transcriptase (TERT) and essential telomerase RNA (TR) component. Beyond merely providing the template for telomeric DNA synthesis, TR is an innate telomerase component and directly facilitates enzymatic function. TR accomplishes this by having evolved structural elements for stable assembly with the TERT protein and the regulation of the telomerase catalytic cycle. Despite its prominence and prevalence, TR has profoundly diverged in length, sequence, and biogenesis pathway among distinct evolutionary lineages. This diversity has generated numerous structural and mechanistic solutions for ensuring proper RNP formation and high fidelity telomeric DNA synthesis. Telomerase provides unique insights into RNA and protein coevolution within RNP enzymes.
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Affiliation(s)
- Joshua D Podlevsky
- a School of Molecular Sciences, Arizona State University , Tempe , AZ , USA
| | - Julian J-L Chen
- a School of Molecular Sciences, Arizona State University , Tempe , AZ , USA
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Jorjani H, Kehr S, Jedlinski DJ, Gumienny R, Hertel J, Stadler PF, Zavolan M, Gruber AR. An updated human snoRNAome. Nucleic Acids Res 2016; 44:5068-82. [PMID: 27174936 PMCID: PMC4914119 DOI: 10.1093/nar/gkw386] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 04/23/2016] [Indexed: 12/18/2022] Open
Abstract
Small nucleolar RNAs (snoRNAs) are a class of non-coding RNAs that guide the post-transcriptional processing of other non-coding RNAs (mostly ribosomal RNAs), but have also been implicated in processes ranging from microRNA-dependent gene silencing to alternative splicing. In order to construct an up-to-date catalog of human snoRNAs we have combined data from various databases, de novo prediction and extensive literature review. In total, we list more than 750 curated genomic loci that give rise to snoRNA and snoRNA-like genes. Utilizing small RNA-seq data from the ENCODE project, our study characterizes the plasticity of snoRNA expression identifying both constitutively as well as cell type specific expressed snoRNAs. Especially, the comparison of malignant to non-malignant tissues and cell types shows a dramatic perturbation of the snoRNA expression profile. Finally, we developed a high-throughput variant of the reverse-transcriptase-based method for identifying 2'-O-methyl modifications in RNAs termed RimSeq. Using the data from this and other high-throughput protocols together with previously reported modification sites and state-of-the-art target prediction methods we re-estimate the snoRNA target RNA interaction network. Our current results assign a reliable modification site to 83% of the canonical snoRNAs, leaving only 76 snoRNA sequences as orphan.
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Affiliation(s)
- Hadi Jorjani
- Computational and Systems Biology, Biozentrum, University of Basel and Swiss Institute of Bioinformatics, Basel CH-4056, Switzerland
| | - Stephanie Kehr
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University of Leipzig, D-04107 Leipzig, Germany
| | - Dominik J Jedlinski
- Computational and Systems Biology, Biozentrum, University of Basel and Swiss Institute of Bioinformatics, Basel CH-4056, Switzerland
| | - Rafal Gumienny
- Computational and Systems Biology, Biozentrum, University of Basel and Swiss Institute of Bioinformatics, Basel CH-4056, Switzerland
| | - Jana Hertel
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University of Leipzig, D-04107 Leipzig, Germany
| | - Peter F Stadler
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University of Leipzig, D-04107 Leipzig, Germany Max Planck Institute for Mathematics in the Sciences, D-04103 Leipzig, Germany RNomics Group, Fraunhofer Institute for Cell Therapy and Immunology, D-04103 Leipzig, Germany Department of Theoretical Chemistry, University of Vienna, A-1090 Vienna, Austria Santa Fe Institute, NM-87501Santa Fe, USA
| | - Mihaela Zavolan
- Computational and Systems Biology, Biozentrum, University of Basel and Swiss Institute of Bioinformatics, Basel CH-4056, Switzerland
| | - Andreas R Gruber
- Computational and Systems Biology, Biozentrum, University of Basel and Swiss Institute of Bioinformatics, Basel CH-4056, Switzerland
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Podlevsky JD, Li Y, Chen JJL. Structure and function of echinoderm telomerase RNA. RNA (NEW YORK, N.Y.) 2016; 22:204-215. [PMID: 26598712 PMCID: PMC4712671 DOI: 10.1261/rna.053280.115] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 10/23/2015] [Indexed: 06/05/2023]
Abstract
Telomerase is a ribonucleoprotein (RNP) enzyme that requires an integral telomerase RNA (TR) subunit, in addition to the catalytic telomerase reverse transcriptase (TERT), for enzymatic function. The secondary structures of TRs from the three major groups of species, ciliates, fungi, and vertebrates, have been studied extensively and demonstrate dramatic diversity. Herein, we report the first comprehensive secondary structure of TR from echinoderms-marine invertebrates closely related to vertebrates-determined by phylogenetic comparative analysis of 16 TR sequences from three separate echinoderm classes. Similar to vertebrate TR, echinoderm TR contains the highly conserved template/pseudoknot and H/ACA domains. However, echinoderm TR lacks the ancestral CR4/5 structural domain found throughout vertebrate and fungal TRs. Instead, echinoderm TR contains a distinct simple helical region, termed eCR4/5, that is functionally equivalent to the CR4/5 domain. The urchin and brittle star eCR4/5 domains bind specifically to their respective TERT proteins and stimulate telomerase activity. Distinct from vertebrate telomerase, the echinoderm TR template/pseudoknot domain with the TERT protein is sufficient to reconstitute significant telomerase activity. This gain-of-function of the echinoderm template/pseudoknot domain for conferring telomerase activity presumably facilitated the rapid structural evolution of the eCR4/5 domain throughout the echinoderm lineage. Additionally, echinoderm TR utilizes the template-adjacent P1.1 helix as a physical template boundary element to prevent nontelomeric DNA synthesis, a mechanism used by ciliate and fungal TRs. Thus, the chimeric and eccentric structural features of echinoderm TR provide unparalleled insights into the rapid evolution of telomerase RNP structure and function.
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Affiliation(s)
- Joshua D Podlevsky
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, USA
| | - Yang Li
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, USA
| | - Julian J-L Chen
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, USA
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Kannan R, Helston RM, Dannebaum RO, Baumann P. Diverse mechanisms for spliceosome-mediated 3' end processing of telomerase RNA. Nat Commun 2015; 6:6104. [PMID: 25598145 PMCID: PMC4299874 DOI: 10.1038/ncomms7104] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 12/15/2014] [Indexed: 11/13/2022] Open
Abstract
The 3′ end of Schizosaccharomyces pombe telomerase RNA (SpTER1) is generated by spliceosomal cleavage, a reaction that corresponds to the first step of splicing. The observation that the spliceosome functions in 3′ end processing raised questions about the evolutionary origin and conservation of this mechanism. We now present data in support of spliceosomes generating 3′ ends of telomerase RNAs in other fungi. Strikingly, the mechanistic basis for restricting spliceosomal splicing to the first transesterification reaction differs substantially among species. Unlike S. pombe, two other fission yeasts rely on hyperstabilization of the U6 snRNA—5′ splice site interaction to impede the 2nd step of splicing. In contrast, a non-canonical 5′ splice site blocks the second transesterification reaction in Aspergillus species. These results demonstrate a conserved role for spliceosomes functioning in 3′ end processing. Divergent mechanisms of uncoupling the two steps of splicing argue for multiple origins of this pathway. In fission yeast, the telomerase RNA (TER) is produced through spliceosomal cleavage. Here, Kannan et al. find that spliceosome-generated 3′ ends also occurs in other fungal TERs using distinct molecular mechanisms, suggesting multiple origins for this type of TER maturation pathway.
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Affiliation(s)
- Ram Kannan
- 1] Stowers Institute for Medical Research, Kansas City, Missouri 64110, USA [2] Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
| | - Rachel M Helston
- Stowers Institute for Medical Research, Kansas City, Missouri 64110, USA
| | | | - Peter Baumann
- 1] Stowers Institute for Medical Research, Kansas City, Missouri 64110, USA [2] Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas 66160, USA [3] Howard Hughes Medical Institute, Kansas City, Missouri 64110, USA
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Abstract
Telomerase is a specialized reverse transcriptase (RT) containing an intrinsic telomerase RNA (TR) component. It synthesizes telomeric DNA repeats, (GGTTAG)n in humans, by reiteratively copying a precisely defined, short template sequence from the integral TR. The specific mechanism of how the telomerase active site uses this short template region accurately and efficiently during processive DNA repeat synthesis has remained elusive. Here we report that the human TR template, in addition to specifying the DNA sequence, is embedded with a single-nucleotide signal to pause DNA synthesis. After the addition of a dT residue to the DNA primer, which is specified by the 49 rA residue in the template, telomerase extends the DNA primer with three additional nucleotides and then pauses DNA synthesis. This sequence-defined pause site coincides precisely with the helix paired region 1 (P1)-defined physical template boundary and precludes the incorporation of nontelomeric nucleotides from residues outside the template region. Furthermore, this sequence-defined pausing mechanism is a key determinant, in addition to the P1-defined template boundary, for generating the characteristic 6-nt ladder banding pattern of telomeric DNA products in vitro. In the absence of the pausing signal, telomerase stalls nucleotide addition at multiple sites along the template, generating DNA products with heterogeneous terminal repeat registers. Our findings demonstrate that this unique self-regulating mechanism of the human TR template is essential for high-fidelity synthesis of DNA repeats.
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Progress in structural studies of telomerase. Curr Opin Struct Biol 2014; 24:115-24. [PMID: 24508601 DOI: 10.1016/j.sbi.2014.01.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 01/01/2014] [Accepted: 01/08/2014] [Indexed: 02/01/2023]
Abstract
Telomerase is the ribonucleoprotein (RNP) reverse transcriptase responsible for synthesizing the 3' ends of linear chromosomes. It plays critical roles in tumorigenesis, cellular aging, and stem cell renewal. The past two years have seen exciting progress in determining telomerase holoenzyme architecture and the structural basis of telomerase activity. Notably, the first electron microscopy structures of telomerase were reported, of the Tetrahymena thermophila telomerase holoenzyme and a human telomerase dimer. In addition to new structures of TERT and TER domains, the first structures of telomerase protein domains beyond TERT, and their complexes with TER or telomeric single-stranded DNA, were reported. Together these studies provide the first glimpse into the organization of the proteins and RNA in the telomerase RNP.
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Gillard GB, Garama DJ, Brown CM. The transcriptome of the NZ endemic sea urchin Kina (Evechinus chloroticus). BMC Genomics 2014; 15:45. [PMID: 24438054 PMCID: PMC3898728 DOI: 10.1186/1471-2164-15-45] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 12/30/2013] [Indexed: 11/10/2022] Open
Abstract
Background Sea urchins are studied as model organisms for developmental and systems biology and also produce highly valued food products. Evechinus chloroticus (Kina) is a sea urchin species that is indigenous to New Zealand. It is the type member of the Evechinus genus based on its morphological characteristics. Previous research has focused on identifying physical factors affecting commercial roe quality of E. chloroticus, but there is almost no genetic information available for E. chloroticus. E. chloroticus is the only species in its genus and has yet to be subject to molecular phylogenetic analysis. Results In this study we performed a de novo transcriptome assembly of Illumina sequencing data. A total of 123 million 100 base length paired-end reads were generated using RNA-Seq libraries from a range of E. chloroticus tissues from two individuals obtained from Fiordland, New Zealand. The assembly resulted in a set of 75,002 transcripts with an accepted read coverage and length, of which 24,655 transcripts could be functionally annotated using protein similarity. Transcripts could be further annotated with Gene Ontology, KEGG Orthology and InterPro terms. With this sequence data we could perform the first phylogenetic analysis of E. chloroticus to other species of its family using multiple genes. When sequences for the mitochondrial nitrogen dehydrogenase genes were compared, E. chloroticus remained outside of a family level clade, which indicated E. chloroticus is indeed a genetically distinct genus within its family. Conclusions This study has produced a large set of E. chloroticus transcripts/proteins along with functional annotations, vastly increasing the amount of genomic data available for this species. This provides a resource for current and future studies on E. chloroticus, either to increase its commercial value, or its use as a model organism. The phylogenetic results provide a basis for further analysis of relationships between E. chloroticus, its family members, and its evolutionary history.
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Affiliation(s)
| | | | - Chris M Brown
- Biochemistry Department, University of Otago, Dunedin, New Zealand.
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Mefford MA, Rafiq Q, Zappulla DC. RNA connectivity requirements between conserved elements in the core of the yeast telomerase RNP. EMBO J 2013; 32:2980-93. [PMID: 24129512 DOI: 10.1038/emboj.2013.227] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 09/23/2013] [Indexed: 12/25/2022] Open
Abstract
Telomerase is a specialized chromosome end-replicating enzyme required for genome duplication in many eukaryotes. An RNA and reverse transcriptase protein subunit comprise its enzymatic core. Telomerase is evolving rapidly, particularly its RNA component. Nevertheless, nearly all telomerase RNAs, including those of H. sapiens and S. cerevisiae, share four conserved structural elements: a core-enclosing helix (CEH), template-boundary element, template, and pseudoknot, in this order along the RNA. It is not clear how these elements coordinate telomerase activity. We find that although rearranging the order of the four conserved elements in the yeast telomerase RNA subunit, TLC1, disrupts activity, the RNA ends can be moved between the template and pseudoknot in vitro and in vivo. However, the ends disrupt activity when inserted between the other structured elements, defining an Area of Required Connectivity (ARC). Within the ARC, we find that only the junction nucleotides between the pseudoknot and CEH are essential. Integrating all of our findings provides a basic map of functional connections in the core of the yeast telomerase RNP and a framework to understand conserved element coordination in telomerase mechanism.
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Affiliation(s)
- Melissa A Mefford
- Department of Biology, The Johns Hopkins University, Baltimore, MD, USA
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