Skip to Content
Merck
  • The TRAPP complex mediates secretion arrest induced by stress granule assembly.

The TRAPP complex mediates secretion arrest induced by stress granule assembly.

The EMBO journal (2019-08-21)
Francesca Zappa, Cathal Wilson, Giuseppe Di Tullio, Michele Santoro, Piero Pucci, Maria Monti, Davide D'Amico, Sandra Pisonero-Vaquero, Rossella De Cegli, Alessia Romano, Moin A Saleem, Elena Polishchuk, Mario Failli, Laura Giaquinto, Maria Antonietta De Matteis
ABSTRACT

The TRAnsport Protein Particle (TRAPP) complex controls multiple membrane trafficking steps and is strategically positioned to mediate cell adaptation to diverse environmental conditions, including acute stress. We have identified the TRAPP complex as a component of a branch of the integrated stress response that impinges on the early secretory pathway. The TRAPP complex associates with and drives the recruitment of the COPII coat to stress granules (SGs) leading to vesiculation of the Golgi complex and arrest of ER export. The relocation of the TRAPP complex and COPII to SGs only occurs in cycling cells and is CDK1/2-dependent, being driven by the interaction of TRAPP with hnRNPK, a CDK substrate that associates with SGs when phosphorylated. In addition, CDK1/2 inhibition impairs TRAPP complex/COPII relocation to SGs while stabilizing them at ER exit sites. Importantly, the TRAPP complex controls the maturation of SGs. SGs that assemble in TRAPP-depleted cells are smaller and are no longer able to recruit RACK1 and Raptor, two TRAPP-interactive signaling proteins, sensitizing cells to stress-induced apoptosis.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Sodium (meta)arsenite, ≥90%
Sigma-Aldrich
Anti-TRAPPC8 antibody produced in rabbit, Prestige Antibodies® Powered by Atlas Antibodies, affinity isolated antibody, buffered aqueous glycerol solution
Sigma-Aldrich
Anti-Puromycin Antibody, clone 12D10, clone 12D10, from mouse
Sigma-Aldrich
Anti-SEC31A antibody produced in rabbit, Prestige Antibodies® Powered by Atlas Antibodies, affinity isolated antibody, buffered aqueous glycerol solution
Sigma-Aldrich
Anti-Actin antibody produced in rabbit, affinity isolated antibody, buffered aqueous solution
Sigma-Aldrich
Cycloheximide, from microbial, ≥94% (TLC)
Sigma-Aldrich
Monoclonal ANTI-FLAG® M2 antibody produced in mouse, 1 mg/mL, clone M2, affinity isolated antibody, buffered aqueous solution (50% glycerol, 10 mM sodium phosphate, and 150 mM NaCl, pH 7.4)
Sigma-Aldrich
Anti-SEC24C antibody produced in rabbit, Prestige Antibodies® Powered by Atlas Antibodies, affinity isolated antibody, buffered aqueous glycerol solution