Proteomic and immunochemical characterization of a role for stathmin in adult neurogenesis.

Stathmin is a developmentally regulated cytosolic protein expressed at high levels in the brain. Two-dimensional differential in-gel electrophoresis and mass spectroscopy of proteins expressed in immature and mature cultures from embryonic rat cerebral cortex identified stathmin among several differentially expressed proteins, consistent with a possible role in neurogenesis. Stathmin immunohistochemistry in adult rodent brain revealed prominent expression in neuroproliferative zones and neuronal migration pathways, a pattern that resembles the expression of doublecortin, which is implicated in neuronal migration. Stathmin immunoreactivity was also associated with neurons undergoing ectopic chain migration into the ischemic striatum and cerebral cortex following focal cerebral ischemia. Reducing the expression of stathmin or doublecortin with an antisense oligonucleotide inhibited the migration of new neurons from the subventricular zone to the olfactory bulb via the rostral migratory stream. These results suggest a role for stathmin in the migration of newborn neurons in the adult brain.