The spinocerebellar ataxias (SCAs) are among the handful of triplet-repeat neurological disorders. This week, Zu et al. create a tetracycline-regulated conditional mouse model of SCA1. They found that when the gene was disabled early in the course of the disease, the pathology was remarkably reversed. Even performance on the complex accelerating rotarod motor task was restored. This is good news for these mice and maybe for the therapeutics of these disorders.
2. FGF and Cortical Laminar Development.
Hiroshi Hasegawa, Shizuko Ashigaki, Masako Takamatsu, Rika Suzuki- Migishima, Norihiko Ohbayashi, Nobuyuki Itoh, Shinji.
The cortex is made up of tightly organized layers of neurons, each with a distinct function. Now, Hasegawa et al. outline a scenario in which signaling by fibroblast growth factor (FGF) and the Pea3 subfamily of Ets transcription factors mediates the migration of subsequent generations of cortical neurons. Their results indicate that the first generation of neurons expresses FGF, which signals back to FGF receptors in cortical progenitor cells, and the progenitors in turn express temporally regulated Pea3 transcription factors. Thus, the elusive "environmental factors" present in the ventricular zone get a name.