Cargando…

The Neurospora crassa exocyst complex tethers Spitzenkörper vesicles to the apical plasma membrane during polarized growth

Fungal hyphae are among the most highly polarized cells. Hyphal polarized growth is supported by tip-directed transport of secretory vesicles, which accumulate temporarily in a stratified manner in an apical vesicle cluster, the Spitzenkörper. The exocyst complex is required for tethering of secreto...

Descripción completa

Detalles Bibliográficos
Autores principales: Riquelme, Meritxell, Bredeweg, Erin L., Callejas-Negrete, Olga, Roberson, Robert W., Ludwig, Sarah, Beltrán-Aguilar, Alejandro, Seiler, Stephan, Novick, Peter, Freitag, Michael
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The American Society for Cell Biology 2014
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3982996/
https://www.ncbi.nlm.nih.gov/pubmed/24523289
http://dx.doi.org/10.1091/mbc.E13-06-0299
_version_ 1782311238545440768
author Riquelme, Meritxell
Bredeweg, Erin L.
Callejas-Negrete, Olga
Roberson, Robert W.
Ludwig, Sarah
Beltrán-Aguilar, Alejandro
Seiler, Stephan
Novick, Peter
Freitag, Michael
author_facet Riquelme, Meritxell
Bredeweg, Erin L.
Callejas-Negrete, Olga
Roberson, Robert W.
Ludwig, Sarah
Beltrán-Aguilar, Alejandro
Seiler, Stephan
Novick, Peter
Freitag, Michael
author_sort Riquelme, Meritxell
collection PubMed
description Fungal hyphae are among the most highly polarized cells. Hyphal polarized growth is supported by tip-directed transport of secretory vesicles, which accumulate temporarily in a stratified manner in an apical vesicle cluster, the Spitzenkörper. The exocyst complex is required for tethering of secretory vesicles to the apical plasma membrane. We determined that the presence of an octameric exocyst complex is required for the formation of a functional Spitzenkörper and maintenance of regular hyphal growth in Neurospora crassa. Two distinct localization patterns of exocyst subunits at the hyphal tip suggest the dynamic formation of two assemblies. The EXO-70/EXO-84 subunits are found at the peripheral part of the Spitzenkörper, which partially coincides with the outer macrovesicular layer, whereas exocyst components SEC-5, -6, -8, and -15 form a delimited crescent at the apical plasma membrane. Localization of SEC-6 and EXO-70 to the plasma membrane and the Spitzenkörper, respectively, depends on actin and microtubule cytoskeletons. The apical region of exocyst-mediated vesicle fusion, elucidated by the plasma membrane–associated exocyst subunits, indicates the presence of an exocytotic gradient with a tip-high maximum that dissipates gradually toward the subapex, confirming the earlier predictions of the vesicle supply center model for hyphal morphogenesis.
format Online
Article
Text
id pubmed-3982996
institution National Center for Biotechnology Information
language English
publishDate 2014
publisher The American Society for Cell Biology
record_format MEDLINE/PubMed
spelling pubmed-39829962014-06-30 The Neurospora crassa exocyst complex tethers Spitzenkörper vesicles to the apical plasma membrane during polarized growth Riquelme, Meritxell Bredeweg, Erin L. Callejas-Negrete, Olga Roberson, Robert W. Ludwig, Sarah Beltrán-Aguilar, Alejandro Seiler, Stephan Novick, Peter Freitag, Michael Mol Biol Cell Articles Fungal hyphae are among the most highly polarized cells. Hyphal polarized growth is supported by tip-directed transport of secretory vesicles, which accumulate temporarily in a stratified manner in an apical vesicle cluster, the Spitzenkörper. The exocyst complex is required for tethering of secretory vesicles to the apical plasma membrane. We determined that the presence of an octameric exocyst complex is required for the formation of a functional Spitzenkörper and maintenance of regular hyphal growth in Neurospora crassa. Two distinct localization patterns of exocyst subunits at the hyphal tip suggest the dynamic formation of two assemblies. The EXO-70/EXO-84 subunits are found at the peripheral part of the Spitzenkörper, which partially coincides with the outer macrovesicular layer, whereas exocyst components SEC-5, -6, -8, and -15 form a delimited crescent at the apical plasma membrane. Localization of SEC-6 and EXO-70 to the plasma membrane and the Spitzenkörper, respectively, depends on actin and microtubule cytoskeletons. The apical region of exocyst-mediated vesicle fusion, elucidated by the plasma membrane–associated exocyst subunits, indicates the presence of an exocytotic gradient with a tip-high maximum that dissipates gradually toward the subapex, confirming the earlier predictions of the vesicle supply center model for hyphal morphogenesis. The American Society for Cell Biology 2014-04-15 /pmc/articles/PMC3982996/ /pubmed/24523289 http://dx.doi.org/10.1091/mbc.E13-06-0299 Text en © 2014 Riquelme 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
Riquelme, Meritxell
Bredeweg, Erin L.
Callejas-Negrete, Olga
Roberson, Robert W.
Ludwig, Sarah
Beltrán-Aguilar, Alejandro
Seiler, Stephan
Novick, Peter
Freitag, Michael
The Neurospora crassa exocyst complex tethers Spitzenkörper vesicles to the apical plasma membrane during polarized growth
title The Neurospora crassa exocyst complex tethers Spitzenkörper vesicles to the apical plasma membrane during polarized growth
title_full The Neurospora crassa exocyst complex tethers Spitzenkörper vesicles to the apical plasma membrane during polarized growth
title_fullStr The Neurospora crassa exocyst complex tethers Spitzenkörper vesicles to the apical plasma membrane during polarized growth
title_full_unstemmed The Neurospora crassa exocyst complex tethers Spitzenkörper vesicles to the apical plasma membrane during polarized growth
title_short The Neurospora crassa exocyst complex tethers Spitzenkörper vesicles to the apical plasma membrane during polarized growth
title_sort neurospora crassa exocyst complex tethers spitzenkörper vesicles to the apical plasma membrane during polarized growth
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3982996/
https://www.ncbi.nlm.nih.gov/pubmed/24523289
http://dx.doi.org/10.1091/mbc.E13-06-0299
work_keys_str_mv AT riquelmemeritxell theneurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT bredewegerinl theneurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT callejasnegreteolga theneurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT robersonrobertw theneurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT ludwigsarah theneurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT beltranaguilaralejandro theneurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT seilerstephan theneurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT novickpeter theneurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT freitagmichael theneurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT riquelmemeritxell neurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT bredewegerinl neurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT callejasnegreteolga neurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT robersonrobertw neurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT ludwigsarah neurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT beltranaguilaralejandro neurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT seilerstephan neurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT novickpeter neurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth
AT freitagmichael neurosporacrassaexocystcomplextethersspitzenkorpervesiclestotheapicalplasmamembraneduringpolarizedgrowth