Substitutions in conserved regions preceding and within the linker affect activity and flexibility of tRNase ZL, the long form of tRNase Z.
The enzyme tRNase Z, a member of the metallo-β-lactamase family, endonucleolytically removes 3' trailers from precursor tRNAs, preparing them for CCA addition and aminoacylation. The short form of tRNase Z, tRNase ZS, functions as a homodimer and is found in all prokaryotes and some eukaryotes....
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2017-01-01
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| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC5646807?pdf=render |
| _version_ | 1818899804053307392 |
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| author | Makenzie Saoura Kyla Pinnock Maria Pujantell-Graell Louis Levinger |
| author_facet | Makenzie Saoura Kyla Pinnock Maria Pujantell-Graell Louis Levinger |
| author_sort | Makenzie Saoura |
| collection | DOAJ |
| description | The enzyme tRNase Z, a member of the metallo-β-lactamase family, endonucleolytically removes 3' trailers from precursor tRNAs, preparing them for CCA addition and aminoacylation. The short form of tRNase Z, tRNase ZS, functions as a homodimer and is found in all prokaryotes and some eukaryotes. The long form, tRNase ZL, related to tRNase ZS through tandem duplication and found only in eukaryotes, possesses ~2,000-fold greater catalytic efficiency than tRNase ZS. tRNase ZL consists of related but diverged amino and carboxy domains connected by a flexible linker (also referred to as a flexible tether) and functions as a monomer. The amino domain retains the flexible arm responsible for substrate recognition and binding while the carboxy domain retains the active site. The linker region was explored by Ala-scanning through two conserved regions of D. melanogaster tRNase Z: NdomTprox, located at the carboxy end of the amino domain proximal to the linker, and Tflex, a flexible site in the linker. Periodic substitutions in a hydrophobic patch (F329 and L332) at the carboxy end of NdomTprox show 2,700 and 670-fold impairment relative to wild type, respectively, accompanied by reduced linker flexibility at N-T inside the Ndom- linker boundary. The Ala substitution for N378 in the Tflex region has 10-fold higher catalytic efficiency than wild type and locally decreased flexibility, while the Ala substitution at R382 reduces catalytic efficiency ~50-fold. These changes in pre-tRNA processing kinetics and protein flexibility are interpreted in light of a recent crystal structure for S. cerevisiae tRNase Z, suggesting transmission of local changes in hydrophobicity into the skeleton of the amino domain. |
| first_indexed | 2024-12-19T19:53:47Z |
| format | Article |
| id | doaj.art-1bea47bb74834e998137b49b6f1762c9 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-19T19:53:47Z |
| publishDate | 2017-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-1bea47bb74834e998137b49b6f1762c92022-12-21T20:07:52ZengPublic Library of Science (PLoS)PLoS ONE1932-62032017-01-011210e018627710.1371/journal.pone.0186277Substitutions in conserved regions preceding and within the linker affect activity and flexibility of tRNase ZL, the long form of tRNase Z.Makenzie SaouraKyla PinnockMaria Pujantell-GraellLouis LevingerThe enzyme tRNase Z, a member of the metallo-β-lactamase family, endonucleolytically removes 3' trailers from precursor tRNAs, preparing them for CCA addition and aminoacylation. The short form of tRNase Z, tRNase ZS, functions as a homodimer and is found in all prokaryotes and some eukaryotes. The long form, tRNase ZL, related to tRNase ZS through tandem duplication and found only in eukaryotes, possesses ~2,000-fold greater catalytic efficiency than tRNase ZS. tRNase ZL consists of related but diverged amino and carboxy domains connected by a flexible linker (also referred to as a flexible tether) and functions as a monomer. The amino domain retains the flexible arm responsible for substrate recognition and binding while the carboxy domain retains the active site. The linker region was explored by Ala-scanning through two conserved regions of D. melanogaster tRNase Z: NdomTprox, located at the carboxy end of the amino domain proximal to the linker, and Tflex, a flexible site in the linker. Periodic substitutions in a hydrophobic patch (F329 and L332) at the carboxy end of NdomTprox show 2,700 and 670-fold impairment relative to wild type, respectively, accompanied by reduced linker flexibility at N-T inside the Ndom- linker boundary. The Ala substitution for N378 in the Tflex region has 10-fold higher catalytic efficiency than wild type and locally decreased flexibility, while the Ala substitution at R382 reduces catalytic efficiency ~50-fold. These changes in pre-tRNA processing kinetics and protein flexibility are interpreted in light of a recent crystal structure for S. cerevisiae tRNase Z, suggesting transmission of local changes in hydrophobicity into the skeleton of the amino domain.http://europepmc.org/articles/PMC5646807?pdf=render |
| spellingShingle | Makenzie Saoura Kyla Pinnock Maria Pujantell-Graell Louis Levinger Substitutions in conserved regions preceding and within the linker affect activity and flexibility of tRNase ZL, the long form of tRNase Z. PLoS ONE |
| title | Substitutions in conserved regions preceding and within the linker affect activity and flexibility of tRNase ZL, the long form of tRNase Z. |
| title_full | Substitutions in conserved regions preceding and within the linker affect activity and flexibility of tRNase ZL, the long form of tRNase Z. |
| title_fullStr | Substitutions in conserved regions preceding and within the linker affect activity and flexibility of tRNase ZL, the long form of tRNase Z. |
| title_full_unstemmed | Substitutions in conserved regions preceding and within the linker affect activity and flexibility of tRNase ZL, the long form of tRNase Z. |
| title_short | Substitutions in conserved regions preceding and within the linker affect activity and flexibility of tRNase ZL, the long form of tRNase Z. |
| title_sort | substitutions in conserved regions preceding and within the linker affect activity and flexibility of trnase zl the long form of trnase z |
| url | http://europepmc.org/articles/PMC5646807?pdf=render |
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