Protein SP2 crucial to neuron creation

A cell cycle regulator protein called Sp2 may be the key to the proper creation of neurons from stem cells, according to research conducted at North Carolina State University. Improved understanding of the function of the protein may enable scientists to program neural stem cells for regeneration in the future.

Troy Ghashghaei and Jon Horowitz, both faculty in NC State’s Department of Molecular Biomedical Sciences and researchers in the Centre for Comparative Medicine and Translational Research wanted to elucidate how Sp2 works. Horrowitz’s previous research had revealed that an abundance of Sp2 in skin-producing stem cells resulted in tumour formation in lab mice.

“We believe the Sp2 must play a fundamental role in the lives of normal stem cells. Trouble ensues when the mechanisms that regulate its activity are overwhelmed due to its excess abundance,” explained Horrowitz.

In contrast to Horrowitz’s experiments, Ghashghaei’s team undertook experiments to get rid of Sp2 in certain neural stem cells in mice, specifically those that produce the major neurons of the brain’s cerebral cortex.

The researchers discovered that a lack of Sp2 disrupted normal cell formation in these stem cells, and abnormal stem cells were unable to produce normal neurons.

“It is interesting that both an overabundance of this protein and a total lack of it results in similar disruptions in how stem cells divide,” Ghashghaei said. “So while this work confirms that Sp2 is absolutely necessary for stem cell function, a lot of questions still remain about what exactly it is regulating, and whether it is present in all stem cells or just a few. We also need to find out if Sp2 deletion or overabundance can produce brain tumours in our mice as in the skin.”

The results are published in Development