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Multiple mechanisms actively target the SUN protein UNC-84 to the inner nuclear membrane

Approximately 100 proteins are targeted to the inner nuclear membrane (INM), where they regulate chromatin and nuclear dynamics. The mechanisms underlying trafficking to the INM are poorly understood. The Caenorhabditis elegans SUN protein UNC-84 is an excellent model to investigate such mechanisms....

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Autores principales: Tapley, Erin C., Ly, Nina, Starr, Daniel A.
Formato: Texto
Lenguaje:English
Publicado: The American Society for Cell Biology 2011
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3093325/
https://www.ncbi.nlm.nih.gov/pubmed/21411627
http://dx.doi.org/10.1091/mbc.E10-08-0733
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author Tapley, Erin C.
Ly, Nina
Starr, Daniel A.
author_facet Tapley, Erin C.
Ly, Nina
Starr, Daniel A.
author_sort Tapley, Erin C.
collection PubMed
description Approximately 100 proteins are targeted to the inner nuclear membrane (INM), where they regulate chromatin and nuclear dynamics. The mechanisms underlying trafficking to the INM are poorly understood. The Caenorhabditis elegans SUN protein UNC-84 is an excellent model to investigate such mechanisms. UNC-84 recruits KASH proteins to the outer nuclear membrane to bridge the nuclear envelope (NE), mediating nuclear positioning. UNC-84 has four targeting sequences: two classical nuclear localization signals, an INM sorting motif, and a signal conserved in mammalian Sun1, the SUN—nuclear envelope localization signal. Mutations in some signals disrupt the timing of UNC-84 nuclear envelope localization, showing that diffusion is not sufficient to move all UNC-84 to the NE. Thus targeting UNC-84 requires an initial step that actively transports UNC-84 from the peripheral endoplasmic reticulum to the NE. Only when all four signals are simultaneously disrupted does UNC-84 completely fail to localize and to function in nuclear migration, meaning that at least three signals function, in part, redundantly to ensure proper targeting of UNC-84. Multiple mechanisms might also be used to target other proteins to the INM, thereby ensuring their proper and timely localization for essential cellular and developmental functions.
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spelling pubmed-30933252011-07-30 Multiple mechanisms actively target the SUN protein UNC-84 to the inner nuclear membrane Tapley, Erin C. Ly, Nina Starr, Daniel A. Mol Biol Cell Articles Approximately 100 proteins are targeted to the inner nuclear membrane (INM), where they regulate chromatin and nuclear dynamics. The mechanisms underlying trafficking to the INM are poorly understood. The Caenorhabditis elegans SUN protein UNC-84 is an excellent model to investigate such mechanisms. UNC-84 recruits KASH proteins to the outer nuclear membrane to bridge the nuclear envelope (NE), mediating nuclear positioning. UNC-84 has four targeting sequences: two classical nuclear localization signals, an INM sorting motif, and a signal conserved in mammalian Sun1, the SUN—nuclear envelope localization signal. Mutations in some signals disrupt the timing of UNC-84 nuclear envelope localization, showing that diffusion is not sufficient to move all UNC-84 to the NE. Thus targeting UNC-84 requires an initial step that actively transports UNC-84 from the peripheral endoplasmic reticulum to the NE. Only when all four signals are simultaneously disrupted does UNC-84 completely fail to localize and to function in nuclear migration, meaning that at least three signals function, in part, redundantly to ensure proper targeting of UNC-84. Multiple mechanisms might also be used to target other proteins to the INM, thereby ensuring their proper and timely localization for essential cellular and developmental functions. The American Society for Cell Biology 2011-05-15 /pmc/articles/PMC3093325/ /pubmed/21411627 http://dx.doi.org/10.1091/mbc.E10-08-0733 Text en © 2011 Tapley 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
Tapley, Erin C.
Ly, Nina
Starr, Daniel A.
Multiple mechanisms actively target the SUN protein UNC-84 to the inner nuclear membrane
title Multiple mechanisms actively target the SUN protein UNC-84 to the inner nuclear membrane
title_full Multiple mechanisms actively target the SUN protein UNC-84 to the inner nuclear membrane
title_fullStr Multiple mechanisms actively target the SUN protein UNC-84 to the inner nuclear membrane
title_full_unstemmed Multiple mechanisms actively target the SUN protein UNC-84 to the inner nuclear membrane
title_short Multiple mechanisms actively target the SUN protein UNC-84 to the inner nuclear membrane
title_sort multiple mechanisms actively target the sun protein unc-84 to the inner nuclear membrane
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3093325/
https://www.ncbi.nlm.nih.gov/pubmed/21411627
http://dx.doi.org/10.1091/mbc.E10-08-0733
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