5CQG

Structure of Tribolium telomerase in complex with the highly specific inhibitor BIBR1532

Summary for 5CQG

• Entry DOI: 10.2210/pdb5cqg/pdb
• Descriptor: Telomerase reverse transcriptase, 2-{[(2E)-3-(naphthalen-2-yl)but-2-enoyl]amino}benzoic acid (3 entities in total)
• Functional Keywords: telomerase reverse transcriptase fold tert bibr15312, telomerase inhibitor, transferase-transferase inhibitor complex, transferase/transferase inhibitor
• Biological source: Tribolium castaneum (Red flour beetle)
• Total number of polymer chains: 2
• Total formula weight: 141840.17

Authors

Bryan, C.,Rice, C.,Hoffman, H.,Harkisheimer, M.,Sweeney, M.,Skordalakes, E. (deposition date: 2015-07-21, release date: 2015-09-09, Last modification date: 2023-09-27)

Primary citation

Bryan, C.,Rice, C.,Hoffman, H.,Harkisheimer, M.,Sweeney, M.,Skordalakes, E.
Structural Basis of Telomerase Inhibition by the Highly Specific BIBR1532.
Structure, 23:1934-1942, 2015

PubMed Abstract: BIBR1532 is a highly specific telomerase inhibitor, although the molecular basis for inhibition is unknown. Here we present the crystal structure of BIBR1532 bound to Tribolium castaneum catalytic subunit of telomerase (tcTERT). BIBR1532 binds to a conserved hydrophobic pocket (FVYL motif) on the outer surface of the thumb domain. The FVYL motif is near TRBD residues that bind the activation domain (CR4/5) of hTER. RNA binding assays show that the human TERT (hTERT) thumb domain binds the P6.1 stem loop of CR4/5 in vitro. hTERT mutations of the FVYL pocket alter wild-type CR4/5 binding and cause telomere attrition in cells. Furthermore, the hTERT FVYL mutations V1025F, N1028H, and V1090M are implicated in dyskeratosis congenita and aplastic anemia, further supporting the biological and clinical relevance of this novel motif. We propose that CR4/5 contacts with the telomerase thumb domain contribute to telomerase ribonucleoprotein assembly and promote enzymatic activity.

PubMed: 26365799
DOI: 10.1016/j.str.2015.08.006

Experimental method

X-RAY DIFFRACTION (2.3 Å)