Interaction and Antagonistic Roles of NF-kappaB and Hes6 in the Regulation of Cortical Neurogenesis

I have no clue what this means and no understanding of what cortical progenitor cells are. Doctor question it is.
 http://mcb.asm.org/content/early/2013/05/15/MCB.01610-12.abstract

ABSTRACT

The involvement of nuclear factor-kappaB (NF-κB) in several processes in the postnatal and adult brain, ranging from neuronal survival to synaptogenesis and plasticity, has been documented. In contrast, little is known about the functions of NF-κB during embryonic brain development. It is shown here that NF-κB is selectively activated in neocortical neural progenitor cells in the developing mouse telencephalon. Blockade of NF-κB activity leads to premature cortical neuronal differentiation and depletion of the progenitor cell pool. Conversely, NF-κB activation causes decreased cortical neurogenesis and expansion of the progenitor cell compartment. This effect is antagonized by the pro-neuronal transcription factor Hes6, which physically and functionally interacts with RelA-containing NF-κB complexes in cortical progenitor cells. In turn, NF-κB exerts an inhibitory effect on the ability of Hes6 to promote cortical neuronal differentiation. These results reveal previously uncharacterized functions, and modes of regulation, for NF-κB and Hes6 during cortical neurogenesis.