Brain development is the first beginning and the last completing process among the developmental stages. During brain development, the Notch-Hedgehog signaling pathways have key roles with many different signaling pathways for proper cell patterning. The Notch pathway has roles in coordination of embryo polarity, neural plasticity and neuron functions. The Sonic-Hedgehog pathway has roles in the coordination of the parameters including timing and positioning during brain development. In our study, we analyzed the expression patterns of the genes related with the notch, sonic-hedgehog signaling pathway (Notch, Shh, Gli, Smo, Patched, Numb, Gsk3, Delta1, Lgr5, Rex1, Bmi1, Cd133). So, brain tissues were obtained in all three trimester embryo and fetus. The Results were correlated with the Results obtained from adult frontal lobe brain tissue. In tissue samples, the gene expression analyses were performed by doing RNA isolation, cDNA synthesis and Real-time PCR analyses. Notch, Shh, Gli, Smo, Patched, Numb, Gsk3, Lgr5, Rex, and Bmi1 genes had higher gene expression levels in the 3th trimester mouse fetal brain tissues than adult mouse brain tissues. Our Results represent that Notch and Sonic-Hedgehog signaling pathways have important role in the 3th trimester in brain development. This work that has done on mouse brain is important because it contains the clues about human brain functions.
Keywords: Brain development, embryogenesis, neurogenesis, Notch signaling pathway, sonic-Hedgehog signaling pathway, gene expression
