First published online December 21, 2006
Development 134, 203e (2007)
© The Company of Biologists Limited
Polarising neurons: enter NAB-1
The correct establishment of either an axon or a dendrite is crucial for
the normal wiring of a functional nervous system. As previously shown, the SAD
serine-threonine kinases are required for such neuronal polarisation and also
for the clustering of synaptic vesicles at neuromuscular junctions. Mei Zhen
and colleagues now shed further light on how SAD functions in neuronal
polarisation (see p.
237). From a yeast two-hybrid screen in C. elegans,
performed to isolate mediators of SAD-1 function, the authors identified
Neurabin (NAB-1) and show that it physically interacts with SAD-1 in vivo and
in vitro. Double sad-1 nab-1 mutants, they report, have polarity
defects, in which synaptic vesicles cluster in both axons and dendrites.
However, only nab-1 mutants have normal vesicle cluster morphology.
The authors propose that NAB-1 acts as a scaffold for SAD-1, interacting with
SAD-1 via PDZ domains. Mammalian neurabins are required for dendrite spine
maturation, but whether they also have an earlier role in axon determination,
as in C. elegans, remains to be determined.
Related articles in Development:
- Neuronal polarity is regulated by a direct interaction between a scaffolding protein, Neurabin, and a presynaptic SAD-1 kinase in Caenorhabditis elegans
- Wesley Hung, Christine Hwang, Michelle D. Po, and Mei Zhen
Development 2007 134: 237-249.
[Abstract]
[Full Text]
