Gene expression affected by loss-of- or gain-of-function of Dmrt3/Dmrta2 in the dorsomedial telencephalon

We then examined the mutant mice that lack both Dmrt3 and Dmrta2 alleles, and found the size of the medial cortex including the hippocampus and the cortical hem was significantly reduced in mutant brains .To further investigate how Dmrt3 and Dmrta2 are involved in the development of the medial cortex, we applied gene expression profiling approach using whole genome DNA microarray to identify genes which are differentially expressed in Dmrt3/Dmrta2-knockdown cells. Cortical cells knocked-down both Dmrt3 and Dmrta2 exhibited a dramatic increase of Pax6 expression in the medial cortex, leading to the precocious neuronal differentiation, and simultaneous knockdown of Pax6 with Dmrt3/Dmrta2 rescued the phenotype. Our results unveil a key mechanism that mammalian Dmrt factors maintain more proliferative potential of neural progenitors by suppressing Pax6 expression in the developing cerebral cortex. We compared gene expression in cells transfected with control siRNAs, two different sets of Dmrt3/Dmrta2 siRNAs (set1 and set2), and a expression vector for Dmrta2, using 3 independent replicates in each group.