Tubulin and glial fibrillary acidic protein gene expression in developing fetal human brain at midgestation

Developmental alterations in the expression of glial fibrillary acidic prot ein (GFAP) and alpha-tubulin were examined at the level of mRNA and protein in human fetal brain between weeks 13-23 of gestation. Except for a transi ent increase at week 15, GFAP expression in the cytoskeletal (CSK) fraction was low until week 17, when it increased steadily to week 23, correspondin g to the phase of glial proliferation. The developmental profile of alpha-t ubulin in the CSK fraction displayed a biphasic pattern, with an initial ri se between weeks 13-16 coinciding with the early phase of neuroblast multip lication, and a second rise between weeks 17-23 corresponding to the phase of glial proliferation. No significant difference in the spatial distributi on of alpha-tubulin was found in different region of brain but GFAP express ion varied with a higher level in cerebellum than that in cerebrum at late midgestation.