Small molecules intercept Notch signaling and the early secretory pathway.
Notch signaling has a pivotal role in numerous cell-fate decisions, and its aberrant activity leads to developmental disorders and cancer. To identify molecules that influence Notch signaling, we screened nearly 17,000 compounds using automated microscopy to monitor the trafficking and processing of a ligand-independent Notch-enhanced GFP (eGFP) reporter. Characterization of hits in vitro by biochemical and cellular assays and in vivo using zebrafish led to five validated compounds, four of which induced accumulation of the reporter at the plasma membrane by inhibiting γ-secretase. One compound, the dihydropyridine FLI-06, disrupted the Golgi apparatus in a manner distinct from that of brefeldin A and golgicide A. FLI-06 inhibited general secretion at a step before exit from the endoplasmic reticulum (ER), which was accompanied by a tubule-to-sheet morphological transition of the ER, rendering FLI-06 the first small molecule acting at such an early stage in secretory traffic. These data highlight the power of phenotypic screening to enable investigations of central cellular signaling pathways.
Leibniz Institut für Altersforschung-Fritz Lipmann Institut, Jena, Germany.
Andreas
A
Krämer
Torben
T
Mentrup
Bertrand
B
Kleizen
Eric
E
Rivera-Milla
Daniela
D
Reichenbach
Christoph
C
Enzensperger
Richard
R
Nohl
Eric
E
Täuscher
Helmar
H
Görls
Aspasia
A
Ploubidou
Christoph
C
Englert
Oliver
O
Werz
Hans-Dieter
HD
Arndt
Christoph
C
Kaether
D053829:Amyloid Precursor Protein Secretases / Q000037:antagonists & inhibitors; D000818:Animals; D004095:Dihydropyridines / Q000737:chemistry / Q000494:pharmacology*; D004721:Endoplasmic Reticulum / Q000187:drug effects* / Q000378:metabolism; D006056:Golgi Apparatus / Q000187:drug effects / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D015394:Molecular Structure; D051880:Receptors, Notch / Q000037:antagonists & inhibitors* / Q000378:metabolism; D055571:Secretory Pathway / Q000187:drug effects*; D015398:Signal Transduction / Q000187:drug effects*; D013329:Structure-Activity Relationship; D015027:Zebrafish / Q000378:metabolism
D004095:Dihydropyridines; D051880:Receptors, Notch; C038806:1,4-dihydropyridine; D053829:Amyloid Precursor Protein Secretases