Distinct and Overlapping Gene Regulatory Networks in BMP- and HDAC-Controlled Cell Fate Determination in the Embryonic Forebrain

Both bone morphogenetic proteins (BMPs) and histone deacetylases (HDACs) have previously been established to play a role in the development of the three major cell types of the central nervous system: neurons, astrocytes, and oligodendrocytes. We have previously established a connection between these two protein families, showing that HDACs suppress BMP-promoted astrogliogenesis in the embryonic striatum. Since HDACs act in the nucleus to effect changes in transcription, an unbiased analysis of their transcriptional targets could shed light on their downstream effects on BMP-signaling. Using neurospheres from the embryonic striatum as an in vitro system to analyze this phenomenon, we have performed microarray expression profiling on BMP2- and trichostatin A (TSA)-treated cultures, followed by validation of the findings with quantitative RT-PCR and protein analysis. Neurospheres from the embryonic striatum were used to analyze cellular differentiation into neurons and astrocytes in vitro. To analyze the role of BMP2 and the HDAC-inhibitor TSA in this system, neurospheres were treated with TSA or BMP2 for 24 h, and mRNA was extracted after 6 and 24 h of the respective treatment.