Structure of Tetrahymena telomerase reveals previously unknown subunits, functions, and interactions

Jiansen Jiang; Henry Chan; Darian D Cash; Edward J Miracco; Rachel R Ogorzalek Loo; Heather E Upton; Duilio Cascio; Reid O'Brien Johnson; Kathleen Collins; Joseph A Loo; Z Hong Zhou; Juli Feigon

doi:10.1126/science.aab4070

Structure of Tetrahymena telomerase reveals previously unknown subunits, functions, and interactions

Science. 2015 Oct 30;350(6260):aab4070. doi: 10.1126/science.aab4070. Epub 2015 Oct 15.

Authors

Affiliations

¹ Department of Chemistry and Biochemistry, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA. Department of Microbiology, Immunology, and Molecular Genetics, UCLA, Los Angeles, CA 90095, USA. California Nanosystems Institute, UCLA, Los Angeles, CA 90095, USA.
² Department of Chemistry and Biochemistry, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA.
³ Department of Biological Chemistry, UCLA, Los Angeles, CA 90095, USA.
⁴ Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
⁵ Department of Chemistry and Biochemistry, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA. UCLA-U.S. Department of Energy (DOE) Institute of Genomics and Proteomics, UCLA, Los Angeles, CA 90095, USA.
⁶ Department of Chemistry and Biochemistry, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA. Department of Biological Chemistry, UCLA, Los Angeles, CA 90095, USA. UCLA-U.S. Department of Energy (DOE) Institute of Genomics and Proteomics, UCLA, Los Angeles, CA 90095, USA.
⁷ Department of Microbiology, Immunology, and Molecular Genetics, UCLA, Los Angeles, CA 90095, USA. California Nanosystems Institute, UCLA, Los Angeles, CA 90095, USA.
⁸ Department of Chemistry and Biochemistry, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA. California Nanosystems Institute, UCLA, Los Angeles, CA 90095, USA. UCLA-U.S. Department of Energy (DOE) Institute of Genomics and Proteomics, UCLA, Los Angeles, CA 90095, USA. feigon@mbi.ucla.edu.

Abstract

Telomerase helps maintain telomeres by processive synthesis of telomere repeat DNA at their 3'-ends, using an integral telomerase RNA (TER) and telomerase reverse transcriptase (TERT). We report the cryo-electron microscopy structure of Tetrahymena telomerase at ~9 angstrom resolution. In addition to seven known holoenzyme proteins, we identify two additional proteins that form a complex (TEB) with single-stranded telomere DNA-binding protein Teb1, paralogous to heterotrimeric replication protein A (RPA). The p75-p45-p19 subcomplex is identified as another RPA-related complex, CST (CTC1-STN1-TEN1). This study reveals the paths of TER in the TERT-TER-p65 catalytic core and single-stranded DNA exit; extensive subunit interactions of the TERT essential N-terminal domain, p50, and TEB; and other subunit identities and structures, including p19 and p45C crystal structures. Our findings provide structural and mechanistic insights into telomerase holoenzyme function.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Catalytic Domain
Cryoelectron Microscopy
Crystallography, X-Ray
DNA, Single-Stranded / chemistry
Holoenzymes / chemistry
Protein Binding
Protein Conformation
Protein Subunits / chemistry
RNA / chemistry*
Replication Protein A / chemistry
Telomerase / chemistry*
Telomere / chemistry
Telomere Homeostasis
Telomere-Binding Proteins
Tetrahymena / enzymology*

Substances

DNA, Single-Stranded
Holoenzymes
Protein Subunits
Replication Protein A
Telomere-Binding Proteins
telomerase RNA
RNA
Telomerase

Associated data

PDB/2N6Q
PDB/5DFM
PDB/5DFN

Abstract

Publication types

MeSH terms

Substances

Associated data

Grants and funding