Cargando…
Coupling spindle position with mitotic exit in budding yeast: The multifaceted role of the small GTPase Tem1
The budding yeast S. cerevisiae divides asymmetrically and is an excellent model system for asymmetric cell division. As for other asymmetrically dividing cells, proper spindle positioning along the mother-daughter polarity axis is crucial for balanced chromosome segregation. Thus, a surveillance me...
Autores principales: | , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Taylor & Francis
2015
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4905282/ https://www.ncbi.nlm.nih.gov/pubmed/26507466 http://dx.doi.org/10.1080/21541248.2015.1109023 |
_version_ | 1782437239642390528 |
---|---|
author | Scarfone, Ilaria Piatti, Simonetta |
author_facet | Scarfone, Ilaria Piatti, Simonetta |
author_sort | Scarfone, Ilaria |
collection | PubMed |
description | The budding yeast S. cerevisiae divides asymmetrically and is an excellent model system for asymmetric cell division. As for other asymmetrically dividing cells, proper spindle positioning along the mother-daughter polarity axis is crucial for balanced chromosome segregation. Thus, a surveillance mechanism named Spindle Position Checkpoint (SPOC) inhibits mitotic exit and cytokinesis until the mitotic spindle is properly oriented, thereby preventing the generation of cells with aberrant ploidies. The small GTPase Tem1 is required to trigger a Hippo-like protein kinase cascade, named Mitotic Exit Network (MEN), that is essential for mitotic exit and cytokinesis but also contributes to correct spindle alignment in metaphase. Importantly, Tem1 is the target of the SPOC, which relies on the activity of the GTPase-activating complex (GAP) Bub2-Bfa1 to keep Tem1 in the GDP-bound inactive form. Tem1 forms a hetero-trimeric complex with Bub2-Bfa1 at spindle poles (SPBs) that accumulates asymmetrically on the bud-directed spindle pole during mitosis when the spindle is properly positioned. In contrast, the complex remains symmetrically localized on both poles of misaligned spindles. We have recently shown that Tem1 residence at SPBs depends on its nucleotide state and, importantly, asymmetry of the Bub2-Bfa1-Tem1 complex does not promote mitotic exit but rather controls spindle positioning. |
format | Online Article Text |
id | pubmed-4905282 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | Taylor & Francis |
record_format | MEDLINE/PubMed |
spelling | pubmed-49052822016-09-13 Coupling spindle position with mitotic exit in budding yeast: The multifaceted role of the small GTPase Tem1 Scarfone, Ilaria Piatti, Simonetta Small GTPases Commentary The budding yeast S. cerevisiae divides asymmetrically and is an excellent model system for asymmetric cell division. As for other asymmetrically dividing cells, proper spindle positioning along the mother-daughter polarity axis is crucial for balanced chromosome segregation. Thus, a surveillance mechanism named Spindle Position Checkpoint (SPOC) inhibits mitotic exit and cytokinesis until the mitotic spindle is properly oriented, thereby preventing the generation of cells with aberrant ploidies. The small GTPase Tem1 is required to trigger a Hippo-like protein kinase cascade, named Mitotic Exit Network (MEN), that is essential for mitotic exit and cytokinesis but also contributes to correct spindle alignment in metaphase. Importantly, Tem1 is the target of the SPOC, which relies on the activity of the GTPase-activating complex (GAP) Bub2-Bfa1 to keep Tem1 in the GDP-bound inactive form. Tem1 forms a hetero-trimeric complex with Bub2-Bfa1 at spindle poles (SPBs) that accumulates asymmetrically on the bud-directed spindle pole during mitosis when the spindle is properly positioned. In contrast, the complex remains symmetrically localized on both poles of misaligned spindles. We have recently shown that Tem1 residence at SPBs depends on its nucleotide state and, importantly, asymmetry of the Bub2-Bfa1-Tem1 complex does not promote mitotic exit but rather controls spindle positioning. Taylor & Francis 2015-10-27 /pmc/articles/PMC4905282/ /pubmed/26507466 http://dx.doi.org/10.1080/21541248.2015.1109023 Text en © 2015 The Author(s). Published with license by Taylor & Francis Group, LLC http://creativecommons.org/licenses/by-nc/3.0/ This is an Open Access article distributed under the terms of the Creative Commons Attribution-Non-Commercial License http://creativecommons.org/licenses/by-nc/3.0/, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. The moral rights of the named author(s) have been asserted. |
spellingShingle | Commentary Scarfone, Ilaria Piatti, Simonetta Coupling spindle position with mitotic exit in budding yeast: The multifaceted role of the small GTPase Tem1 |
title | Coupling spindle position with mitotic exit in budding yeast: The multifaceted role of the small GTPase Tem1 |
title_full | Coupling spindle position with mitotic exit in budding yeast: The multifaceted role of the small GTPase Tem1 |
title_fullStr | Coupling spindle position with mitotic exit in budding yeast: The multifaceted role of the small GTPase Tem1 |
title_full_unstemmed | Coupling spindle position with mitotic exit in budding yeast: The multifaceted role of the small GTPase Tem1 |
title_short | Coupling spindle position with mitotic exit in budding yeast: The multifaceted role of the small GTPase Tem1 |
title_sort | coupling spindle position with mitotic exit in budding yeast: the multifaceted role of the small gtpase tem1 |
topic | Commentary |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4905282/ https://www.ncbi.nlm.nih.gov/pubmed/26507466 http://dx.doi.org/10.1080/21541248.2015.1109023 |
work_keys_str_mv | AT scarfoneilaria couplingspindlepositionwithmitoticexitinbuddingyeastthemultifacetedroleofthesmallgtpasetem1 AT piattisimonetta couplingspindlepositionwithmitoticexitinbuddingyeastthemultifacetedroleofthesmallgtpasetem1 |