First published online April 13, 2007
Development 134, 901e (2007)
© The Company of Biologists Limited
Endocytosis regenerated
The regenerative ability of planarians is truly remarkable - they can
regenerate their entire body from a tiny tissue fragment. Of particular
interest is how the brain regenerates. On
p. 1679, Agata and
colleagues now show that the planarian clathrin heavy chain
(DjCHC) gene, which functions in endocytosis, is required for neurite
extension and maintenance during regeneration but not for neuronal
differentiation. They used a novel in vitro cell culture system in which
primary cultures of planarian neurons from regenerated heads were sorted
(according to neuronal marker expression) by fluorescence-activated cell
sorting (FACS), following the RNAi knockdown of genes that are expressed in
the regenerating CNS. This in vitro assay revealed that neurite extension but
not neuronal differentiation depends on DjCHC. In uncut planarians,
the patterning and differentiation of neural cells is normal despite the RNAi
knockdown of DjCHC; however, neurites subsequently regress and neural
cells die, resulting in an atrophied CNS. This surprising link between
endocytosis and CNS regeneration will be of interest to both neurobiologists
and investigators of regeneration.
Related articles in Development:
- Clathrin-mediated endocytic signals are required for the regeneration of, as well as homeostasis in, the planarian CNS
- Takeshi Inoue, Tetsutaro Hayashi, Katsuaki Takechi, and Kiyokazu Agata
Development 2007 134: 1679-1689.
[Abstract]
[Full Text]
