Sabrice Guerrier
Long Island University

"Transcriptional Regulation of Genes Controlling Oligodendrocyte Progenitor Proliferation and Differentiation."

Mentors

Dr. Patrizia Casaccia-Bonnefil
Mr. Johnny Kim
Department of Neuroscience, UMDNJ-RWMS

The process by which progenitors become mature oligodendrocytes involves three events: proliferation, growth arrest, and differentiation. Studies have shown that cyclin dependent kinases play a major role in controlling progenitor proliferation. Cyclin E and p27 act as positive and negative regulators of cyclin dependent kinase 2 respectively, and loss of p27 results in increased proliferation. Since growth arrest is essential for differentiation, and is characterized by loss of positive regulators of cell division, we asked whether these were regulated transcriptionally. In order to study gene regulation at the RNA level, messenger RNA was isolated from progenitors (0 day) G1 arrested cells (1 day) and mature oligodendrocytes (5 day) and reverse transcribed. The presence of gene expression was evaluated by a polymerase chain reaction.. Our hypothesis would predict that the expression of genes responsible for proliferation should decrease as cells reach day 5, as should genes that inhibit differentiation. These experiments will demonstrate that transcriptional regulation of cell cycle genes is involved in cell cycle withdrawal which is essential for oligodendrocyte differentiation.