Myrip couples the capture of secretory granules by the actin-rich cell cortex and their attachment to the plasma membrane. - Archive ouverte HAL Access content directly
Journal Articles Journal of Neuroscience Year : 2012

Myrip couples the capture of secretory granules by the actin-rich cell cortex and their attachment to the plasma membrane.

(1) , (2) , (2) , (2) , (2) , (2) , (2) , (2)
1
2

Abstract

Exocytosis of secretory granules (SGs) requires their delivery to the actin-rich cell cortex followed by their attachment to the plasma membrane (PM). How these reactions are executed and coordinated is still unclear. Myrip, which is also known as Slac-2c, binds to the SG-associated GTPase Rab27 and is thought to promote the delivery of SGs to the PM by recruiting the molecular motor myosin Va. Myrip also interacts with actin and the exocyst complex, suggesting that it may exert multiple roles in the secretory process. By combining total internal reflection fluorescence microscopy, single-particle tracking, a photoconversion-based assay, and mathematical modeling, we show that, in human enterochromaffin cells, Myrip (1) inhibits a class of SG motion characterized by fast and directed movement, suggesting that it facilitates the dissociation of SGs from microtubules; (2) enhances their motion toward the PM and the probability of SG attachment to the PM; and (3) increases the characteristic time of immobilization at the PM, indicating that it is a component of the molecular machinery that tether SGs to the PM. Remarkably, while the first two effects of Myrip depend on its ability to recruit myosin Va on SGs, the third is myosin Va independent but relies on the C-terminal domain of Myrip. We conclude that Myrip couples the retention of SGs in the cell cortex, their transport to the PM, and their attachment to the PM, and thus promotes secretion. These three steps of the secretory process are thus intimately coordinated.
Fichier principal
Vignette du fichier
Huet-JNeuroSci-2012.pdf (2.63 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive
Loading...

Dates and versions

inserm-00679404 , version 1 (15-08-2012)

Identifiers

Cite

Sébastien Huet, Isabelle Fanget, Ouardane Jouannot, Patricia Meireles, Tim Zeiske, et al.. Myrip couples the capture of secretory granules by the actin-rich cell cortex and their attachment to the plasma membrane.. Journal of Neuroscience, 2012, 32 (7), pp.2564-77. ⟨10.1523/JNEUROSCI.2724-11.2012⟩. ⟨inserm-00679404⟩
227 View
335 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More