First published online March 23, 2006
Development 133, 801e (2006)
© The Company of Biologists Limited
Pioneering work on cracking neuron codes
During nervous system development, combinatorial codes of transcription
factors specify different neuronal subclasses. But how is each neuron's
identity within a subclass specified? Garces and Thor provide new insights
into this question by reporting that a unique genetic cascade specifies the
fate of the aCC motoneuron in Drosophila, one of seven unique
motoneurons in the intersegmental motor nerve (ISN; see p.
1445). Neurons of the
ISN neuronal subclass express the regulatory factors even-skipped and
zfh1 (which specify this subclass), and grain, a GATA
transcription factor. Although these regulators are expressed by all seven ISN
motoneurons, the researchers show that they only act together in a genetic
cascade (in which even-skipped regulates grain, which
regulates zfh1) to specify the aCC motoneuron the first,
pioneer, neuron to innervate this nerve's target muscle. Why this cascade is
only active in the aCC motoneuron is unclear but might depend on the history
of each ISN motoneuron.
Related articles in Development:
- Specification of Drosophila aCC motoneuron identity by a genetic cascade involving even-skipped, grain and zfh1
- Alain Garces and Stefan Thor
Development 2006 133: 1445-1455.
[Abstract]
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