INVESTIGADORES
BOCCACCIO Graciela Lidia
artículos
Título:
Mammalian Staufen 1 is recruited to stress granules and impairs their assembly (SELECTED FOR "IN THIS ISSUE")
Autor/es:
THOMAS, M.G.;; MARTINEZ TOSAR LJ; DESBATS MA; LEISHMAN CC; BOCCACCIO, GRACIELA L.
Revista:
JOURNAL OF CELL SCIENCE
Editorial:
COMPANY OF BIOLOGISTS LTD
Referencias:
Año: 2009 vol. 122 p. 563 - 573
ISSN:
0021-9533
Resumen:
Stress granules are cytoplasmic mRNA-silencing foci that form
transiently during the stress response. Stress granules harbor
abortive translation initiation complexes and are in dynamic
equilibrium with translating polysomes. Mammalian Staufen 1
(Stau1) is a ubiquitous double-stranded RNA-binding protein
associated with polysomes. Here, we show that Stau1 is recruited
to stress granules upon induction of endoplasmic reticulum or
oxidative stress as well in stress granules induced by translation
initiation blockers. We found that stress granules lacking Stau1
formed in cells depleted of this molecule, indicating that Stau1
is not an essential component of stress granules. Moreover, Stau1
knockdown facilitated stress granule formation upon stress
induction. Conversely, transient transfection of Stau1 impaired
stress granule formation upon stress or pharmacological
initiation arrest. The inhibitory capacity of Stau1 mapped to
the amino-terminal half of the molecule, a region known to bind
to polysomes. We found that the fraction of polysomes
remaining upon stress induction was enriched in Stau1, and
that Stau1 overexpression stabilized polysomes against stress.
We propose that Stau1 is involved in recovery from stress by
stabilizing polysomes, thus helping stress granule dissolution.