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ATP utilization by a DEAD-box protein during refolding of a misfolded group I intron ribozyme
DEAD-box helicase proteins perform ATP-dependent rearrangements of structured RNAs throughout RNA biology. Short RNA helices are unwound in a single ATPase cycle, but the ATP requirement for more complex RNA structural rearrangements is unknown. Here we measure the amount of ATP used for native refo...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
American Society for Biochemistry and Molecular Biology
2020
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7948464/ https://www.ncbi.nlm.nih.gov/pubmed/33262215 http://dx.doi.org/10.1074/jbc.RA120.015029 |
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author | Jarmoskaite, Inga Tijerina, Pilar Russell, Rick |
author_facet | Jarmoskaite, Inga Tijerina, Pilar Russell, Rick |
author_sort | Jarmoskaite, Inga |
collection | PubMed |
description | DEAD-box helicase proteins perform ATP-dependent rearrangements of structured RNAs throughout RNA biology. Short RNA helices are unwound in a single ATPase cycle, but the ATP requirement for more complex RNA structural rearrangements is unknown. Here we measure the amount of ATP used for native refolding of a misfolded group I intron ribozyme by CYT-19, a Neurospora crassa DEAD-box protein that functions as a general chaperone for mitochondrial group I introns. By comparing the rates of ATP hydrolysis and ribozyme refolding, we find that several hundred ATP molecules are hydrolyzed during refolding of each ribozyme molecule. After subtracting nonproductive ATP hydrolysis that occurs in the absence of ribozyme refolding, we find that approximately 100 ATPs are hydrolyzed per refolded RNA as a consequence of interactions specific to the misfolded ribozyme. This value is insensitive to changes in ATP and CYT-19 concentration and decreases with decreasing ribozyme stability. Because of earlier findings that ∼90% of global ribozyme unfolding cycles lead back to the kinetically preferred misfolded conformation and are not observed, we estimate that each global unfolding cycle consumes ∼10 ATPs. Our results indicate that CYT-19 functions as a general RNA chaperone by using a stochastic, energy-intensive mechanism to promote RNA unfolding and refolding, suggesting an evolutionary convergence with protein chaperones. |
format | Online Article Text |
id | pubmed-7948464 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | American Society for Biochemistry and Molecular Biology |
record_format | MEDLINE/PubMed |
spelling | pubmed-79484642021-03-19 ATP utilization by a DEAD-box protein during refolding of a misfolded group I intron ribozyme Jarmoskaite, Inga Tijerina, Pilar Russell, Rick J Biol Chem Research Article DEAD-box helicase proteins perform ATP-dependent rearrangements of structured RNAs throughout RNA biology. Short RNA helices are unwound in a single ATPase cycle, but the ATP requirement for more complex RNA structural rearrangements is unknown. Here we measure the amount of ATP used for native refolding of a misfolded group I intron ribozyme by CYT-19, a Neurospora crassa DEAD-box protein that functions as a general chaperone for mitochondrial group I introns. By comparing the rates of ATP hydrolysis and ribozyme refolding, we find that several hundred ATP molecules are hydrolyzed during refolding of each ribozyme molecule. After subtracting nonproductive ATP hydrolysis that occurs in the absence of ribozyme refolding, we find that approximately 100 ATPs are hydrolyzed per refolded RNA as a consequence of interactions specific to the misfolded ribozyme. This value is insensitive to changes in ATP and CYT-19 concentration and decreases with decreasing ribozyme stability. Because of earlier findings that ∼90% of global ribozyme unfolding cycles lead back to the kinetically preferred misfolded conformation and are not observed, we estimate that each global unfolding cycle consumes ∼10 ATPs. Our results indicate that CYT-19 functions as a general RNA chaperone by using a stochastic, energy-intensive mechanism to promote RNA unfolding and refolding, suggesting an evolutionary convergence with protein chaperones. American Society for Biochemistry and Molecular Biology 2020-12-05 /pmc/articles/PMC7948464/ /pubmed/33262215 http://dx.doi.org/10.1074/jbc.RA120.015029 Text en © 2020 The Authors https://creativecommons.org/licenses/by/4.0/This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Research Article Jarmoskaite, Inga Tijerina, Pilar Russell, Rick ATP utilization by a DEAD-box protein during refolding of a misfolded group I intron ribozyme |
title | ATP utilization by a DEAD-box protein during refolding of a misfolded group I intron ribozyme |
title_full | ATP utilization by a DEAD-box protein during refolding of a misfolded group I intron ribozyme |
title_fullStr | ATP utilization by a DEAD-box protein during refolding of a misfolded group I intron ribozyme |
title_full_unstemmed | ATP utilization by a DEAD-box protein during refolding of a misfolded group I intron ribozyme |
title_short | ATP utilization by a DEAD-box protein during refolding of a misfolded group I intron ribozyme |
title_sort | atp utilization by a dead-box protein during refolding of a misfolded group i intron ribozyme |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7948464/ https://www.ncbi.nlm.nih.gov/pubmed/33262215 http://dx.doi.org/10.1074/jbc.RA120.015029 |
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