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Localization of Pom121 to the inner nuclear membrane is required for an early step of interphase nuclear pore complex assembly

The nuclear pore complex (NPC) is a large protein assembly that mediates molecular trafficking between the cytoplasm and the nucleus. NPCs assemble twice during the cell cycle in metazoans: postmitosis and during interphase. In this study, using small interfering RNA (siRNA) in conjunction with a ce...

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Detalles Bibliográficos
Autores principales: Funakoshi, Tomoko, Clever, Michaela, Watanabe, Ai, Imamoto, Naoko
Formato: Texto
Lenguaje:English
Publicado: The American Society for Cell Biology 2011
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3069009/
https://www.ncbi.nlm.nih.gov/pubmed/21289085
http://dx.doi.org/10.1091/mbc.E10-07-0641
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author Funakoshi, Tomoko
Clever, Michaela
Watanabe, Ai
Imamoto, Naoko
author_facet Funakoshi, Tomoko
Clever, Michaela
Watanabe, Ai
Imamoto, Naoko
author_sort Funakoshi, Tomoko
collection PubMed
description The nuclear pore complex (NPC) is a large protein assembly that mediates molecular trafficking between the cytoplasm and the nucleus. NPCs assemble twice during the cell cycle in metazoans: postmitosis and during interphase. In this study, using small interfering RNA (siRNA) in conjunction with a cell fusion–based NPC assembly assay, we demonstrated that pore membrane protein (Pom)121, a vertebrate-specific integral membrane nucleoporin, is indispensable for an early step in interphase NPC assembly. Functional domain analysis of Pom121 showed that its nuclear localization signals, which bind to importin β via importin α and likely function with RanGTP, play an essential role in targeting Pom121 to the interphase NPC. Furthermore, a region of Pom121 that interacts with the inner nuclear membrane (INM) and lamin B receptor was found to be crucial for its NPC targeting. Based on these findings and on evidence that Pom121 localizes at the INM in the absence of a complete NPC structure, we propose that the nuclear migration of Pom121 and its subsequent interaction with INM proteins are required to initiate interphase NPC assembly. Our data also suggest, for the first time, the importance of the INM as a seeding site for “prepores” during interphase NPC assembly.
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spelling pubmed-30690092011-06-16 Localization of Pom121 to the inner nuclear membrane is required for an early step of interphase nuclear pore complex assembly Funakoshi, Tomoko Clever, Michaela Watanabe, Ai Imamoto, Naoko Mol Biol Cell Articles The nuclear pore complex (NPC) is a large protein assembly that mediates molecular trafficking between the cytoplasm and the nucleus. NPCs assemble twice during the cell cycle in metazoans: postmitosis and during interphase. In this study, using small interfering RNA (siRNA) in conjunction with a cell fusion–based NPC assembly assay, we demonstrated that pore membrane protein (Pom)121, a vertebrate-specific integral membrane nucleoporin, is indispensable for an early step in interphase NPC assembly. Functional domain analysis of Pom121 showed that its nuclear localization signals, which bind to importin β via importin α and likely function with RanGTP, play an essential role in targeting Pom121 to the interphase NPC. Furthermore, a region of Pom121 that interacts with the inner nuclear membrane (INM) and lamin B receptor was found to be crucial for its NPC targeting. Based on these findings and on evidence that Pom121 localizes at the INM in the absence of a complete NPC structure, we propose that the nuclear migration of Pom121 and its subsequent interaction with INM proteins are required to initiate interphase NPC assembly. Our data also suggest, for the first time, the importance of the INM as a seeding site for “prepores” during interphase NPC assembly. The American Society for Cell Biology 2011-04-01 /pmc/articles/PMC3069009/ /pubmed/21289085 http://dx.doi.org/10.1091/mbc.E10-07-0641 Text en © 2011 Funakoshi et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0). “ASCB®,“ “The American Society for Cell Biology®,” and “Molecular Biology of the Cell®” are registered trademarks of The American Society of Cell Biology.
spellingShingle Articles
Funakoshi, Tomoko
Clever, Michaela
Watanabe, Ai
Imamoto, Naoko
Localization of Pom121 to the inner nuclear membrane is required for an early step of interphase nuclear pore complex assembly
title Localization of Pom121 to the inner nuclear membrane is required for an early step of interphase nuclear pore complex assembly
title_full Localization of Pom121 to the inner nuclear membrane is required for an early step of interphase nuclear pore complex assembly
title_fullStr Localization of Pom121 to the inner nuclear membrane is required for an early step of interphase nuclear pore complex assembly
title_full_unstemmed Localization of Pom121 to the inner nuclear membrane is required for an early step of interphase nuclear pore complex assembly
title_short Localization of Pom121 to the inner nuclear membrane is required for an early step of interphase nuclear pore complex assembly
title_sort localization of pom121 to the inner nuclear membrane is required for an early step of interphase nuclear pore complex assembly
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3069009/
https://www.ncbi.nlm.nih.gov/pubmed/21289085
http://dx.doi.org/10.1091/mbc.E10-07-0641
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