The Petritsch lab at UCSF investigates many processes of one of the most important organ in the body, the brain. One of your main goals is to understand the development and maturation of myelinating cells called oligodendrocytes (OLG). OLG cells constituting 2-9% of the total cells in the adult brain are the largest proliferating population. These unique cells originate from oligodendrocyte precursor cells (OPC) that express the NG2 chondroitin sulfate proteoglycan. NG2 + OPC’s have been shown to evenly distribute in the adult brain and remain actively dividing while generating myelinating OLG in grey and white matter tracks including the corpus callosum while remaining committed to the OL linage beyond the perinatal stages. OPC use the evolutionarily conserved process of asymmetric cell division (ACD) to self-renew and differentiate. This process is achieved by polarity proteins, which provide the cells with cues and instruct cell fate determinates to localize unequally throughout the cell, along with properly orientating the spindle fibers. This allows cells to create daughter cells with distinct fates after cytokinesis. We have begun to investigate the WD40 domain polarity protein Lgl1 role in these conserved processes. We have found that Lgl1 is expressed in premyelinating and myelinating OLG in the postnatal and adult brain. We have also shown that Lgl1 regulates ACD and differentiation of corpus callosum derived cells in vitro. Will are now beginning to explore in vivo function of Lgl1 in the adult and postnatal brain though the use on and Lgl1 conditional knockout mouse model where Lgl1 is excised from NG2+ cells.