Article

Image-based screening identifies novel roles for IkappaB kinase and glycogen synthase kinase 3 in axonal degeneration.

Department of Genetics, Washington University Medical School, St Louis, Missouri 63110, USA.
Journal of Biological Chemistry (impact factor: 4.77). 06/2011; 286(32):28011-8. DOI:10.1074/jbc.M111.250472
Source: PubMed

ABSTRACT Axon degeneration is an active, evolutionarily conserved self-destruction program by which compromised axons fragment in response to varied insults. Unlike programmed cell death, axon degeneration is poorly understood. We have combined robotic liquid handling with automated microscopy and image analysis to create a robust screening platform to measure axon degeneration in mammalian primary neuronal cultures. Using this assay, we performed an unbiased screen of 480 bioactive compounds, identifying 11 that reproducibly delay fragmentation of severed axons in vitro, including two inhibitors of glycogen synthase kinase 3 and two inhibitors of IκB kinase. Knockdown of each of these targets by shRNA lentivirus also delays axon degeneration in vitro, further supporting their role in the axon degeneration program.

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Keywords

480 bioactive compounds
 
active
 
Axon degeneration
 
axon degeneration program
 
compromised axons fragment
 
evolutionarily conserved self-destruction program
 
glycogen synthase kinase 3
 
inhibitors
 
IκB kinase
 
mammalian primary neuronal cultures
 
measure axon degeneration
 
reproducibly delay fragmentation
 
robotic liquid handling
 
robust screening platform
 
shRNA lentivirus
 
unbiased screen