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Cdc5-Dependent Asymmetric Localization of Bfa1 Fine-Tunes Timely Mitotic Exit
In budding yeast, the major regulator of the mitotic exit network (MEN) is Tem1, a GTPase, which is inhibited by the GTPase-activating protein (GAP), Bfa1/Bub2. Asymmetric Bfa1 localization to the bud-directed spindle pole body (SPB) during metaphase also controls mitotic exit, but the molecular mec...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
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Public Library of Science
2012
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3257293/ https://www.ncbi.nlm.nih.gov/pubmed/22253605 http://dx.doi.org/10.1371/journal.pgen.1002450 |
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author | Kim, Junwon Luo, Guangming Bahk, Young Yil Song, Kiwon |
author_facet | Kim, Junwon Luo, Guangming Bahk, Young Yil Song, Kiwon |
author_sort | Kim, Junwon |
collection | PubMed |
description | In budding yeast, the major regulator of the mitotic exit network (MEN) is Tem1, a GTPase, which is inhibited by the GTPase-activating protein (GAP), Bfa1/Bub2. Asymmetric Bfa1 localization to the bud-directed spindle pole body (SPB) during metaphase also controls mitotic exit, but the molecular mechanism and function of this localization are not well understood, particularly in unperturbed cells. We identified four novel Cdc5 target residues within the Bfa1 C-terminus: (452)S, (453)S, (454)S, and (559)S. A Bfa1 mutant in which all of these residues had been changed to alanine (Bfa1(4A)) persisted on both SPBs at anaphase and was hypo-phosphorylated, despite retaining its GAP activity for Tem1. A Bfa1 phospho-mimetic mutant in which all of these residues were switched to aspartate (Bfa1(4D)) always localized asymmetrically to the SPB. These observations demonstrate that asymmetric localization of Bfa1 is tightly linked to its Cdc5-dependent phosphorylation, but not to its GAP activity. Consistent with this, in kinase-defective cdc5-2 cells Bfa1 was not phosphorylated and localized to both SPBs, whereas Bfa1(4D) was asymmetrically localized. BFA1(4A) cells progressed through anaphase normally but displayed delayed mitotic exit in unperturbed cell cycles, while BFA1(4D) cells underwent mitotic exit with the same kinetics as wild-type cells. We suggest that Cdc5 induces the asymmetric distribution of Bfa1 to the bud-directed SPB independently of Bfa1 GAP activity at anaphase and that Bfa1 asymmetry fine-tunes the timing of MEN activation in unperturbed cell cycles. |
format | Online Article Text |
id | pubmed-3257293 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2012 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-32572932012-01-17 Cdc5-Dependent Asymmetric Localization of Bfa1 Fine-Tunes Timely Mitotic Exit Kim, Junwon Luo, Guangming Bahk, Young Yil Song, Kiwon PLoS Genet Research Article In budding yeast, the major regulator of the mitotic exit network (MEN) is Tem1, a GTPase, which is inhibited by the GTPase-activating protein (GAP), Bfa1/Bub2. Asymmetric Bfa1 localization to the bud-directed spindle pole body (SPB) during metaphase also controls mitotic exit, but the molecular mechanism and function of this localization are not well understood, particularly in unperturbed cells. We identified four novel Cdc5 target residues within the Bfa1 C-terminus: (452)S, (453)S, (454)S, and (559)S. A Bfa1 mutant in which all of these residues had been changed to alanine (Bfa1(4A)) persisted on both SPBs at anaphase and was hypo-phosphorylated, despite retaining its GAP activity for Tem1. A Bfa1 phospho-mimetic mutant in which all of these residues were switched to aspartate (Bfa1(4D)) always localized asymmetrically to the SPB. These observations demonstrate that asymmetric localization of Bfa1 is tightly linked to its Cdc5-dependent phosphorylation, but not to its GAP activity. Consistent with this, in kinase-defective cdc5-2 cells Bfa1 was not phosphorylated and localized to both SPBs, whereas Bfa1(4D) was asymmetrically localized. BFA1(4A) cells progressed through anaphase normally but displayed delayed mitotic exit in unperturbed cell cycles, while BFA1(4D) cells underwent mitotic exit with the same kinetics as wild-type cells. We suggest that Cdc5 induces the asymmetric distribution of Bfa1 to the bud-directed SPB independently of Bfa1 GAP activity at anaphase and that Bfa1 asymmetry fine-tunes the timing of MEN activation in unperturbed cell cycles. Public Library of Science 2012-01-12 /pmc/articles/PMC3257293/ /pubmed/22253605 http://dx.doi.org/10.1371/journal.pgen.1002450 Text en Kim et al. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited. |
spellingShingle | Research Article Kim, Junwon Luo, Guangming Bahk, Young Yil Song, Kiwon Cdc5-Dependent Asymmetric Localization of Bfa1 Fine-Tunes Timely Mitotic Exit |
title | Cdc5-Dependent Asymmetric Localization of Bfa1 Fine-Tunes Timely Mitotic Exit |
title_full | Cdc5-Dependent Asymmetric Localization of Bfa1 Fine-Tunes Timely Mitotic Exit |
title_fullStr | Cdc5-Dependent Asymmetric Localization of Bfa1 Fine-Tunes Timely Mitotic Exit |
title_full_unstemmed | Cdc5-Dependent Asymmetric Localization of Bfa1 Fine-Tunes Timely Mitotic Exit |
title_short | Cdc5-Dependent Asymmetric Localization of Bfa1 Fine-Tunes Timely Mitotic Exit |
title_sort | cdc5-dependent asymmetric localization of bfa1 fine-tunes timely mitotic exit |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3257293/ https://www.ncbi.nlm.nih.gov/pubmed/22253605 http://dx.doi.org/10.1371/journal.pgen.1002450 |
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