Genome-wide RNAi screening identifies human proteins with a regulatory function in the early secretory pathway.
The secretory pathway in mammalian cells has evolved to facilitate the transfer of cargo molecules to internal and cell surface membranes. Use of automated microscopy-based genome-wide RNA interference screens in cultured human cells allowed us to identify 554 proteins influencing secretion. Cloning, fluorescent-tagging and subcellular localization analysis of 179 of these proteins revealed that more than two-thirds localize to either the cytoplasm or membranes of the secretory and endocytic pathways. The depletion of 143 of them resulted in perturbations in the organization of the COPII and/or COPI vesicular coat complexes of the early secretory pathway, or the morphology of the Golgi complex. Network analyses revealed a so far unappreciated link between early secretory pathway function, small GTP-binding protein regulation, actin cytoskeleton organization and EGF-receptor-mediated signalling. This work provides an important resource for an integrative understanding of global cellular organization and regulation of the secretory pathway in mammalian cells.
School of Biology and Environmental Science & Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin 4, Ireland. jeremy.simpson@ucd.ie
Jeremy C
JC
Simpson
Brigitte
B
Joggerst
Vibor
V
Laketa
Fatima
F
Verissimo
Cihan
C
Cetin
Holger
H
Erfle
Mariana G
MG
Bexiga
Vasanth R
VR
Singan
Jean-Karim
JK
Hériché
Beate
B
Neumann
Alvaro
A
Mateos
Jonathon
J
Blake
Stephanie
S
Bechtel
Vladimir
V
Benes
Stefan
S
Wiemann
Jan
J
Ellenberg
Rainer
R
Pepperkok
D008841:Actin Cytoskeleton / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D004705:Endocytosis / Q000235:genetics*; D004815:Epidermal Growth Factor / Q000378:metabolism; D005786:Gene Expression Regulation; D053263:Gene Regulatory Networks; D006056:Golgi Apparatus / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D008856:Microscopy, Fluorescence; D020559:Monomeric GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism; D010982:Platelet-Derived Growth Factor / Q000378:metabolism; D021381:Protein Transport / Q000235:genetics; D034622:RNA Interference; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D022142:Secretory Vesicles / Q000378:metabolism*; D015398:Signal Transduction / Q000235:genetics; D013997:Time Factors; D014162:Transfection; D022161:Transport Vesicles / Q000378:metabolism*
D010982:Platelet-Derived Growth Factor; D011993:Recombinant Fusion Proteins; D004815:Epidermal Growth Factor; D020559:Monomeric GTP-Binding Proteins