19-P030 Mechanisms controlling neurogenic versus self-renewing cell divisions during spinal cord regeneration in Ambystoma mexicanum

the satellite cells. Contaminating CD45+/Mac-1+/Sca-1+ cells were subsequently removed by MACS cell separation. Cell cycle analysis revealed that over 80% of the resulting myogenic cell population was in G0, indicating a high proportion of quiescent cells in the isolated population. RT-PCR analysis showed that the expression of three Kruppel-like factors (Klf) was increased in quiescent satellite cells and decreased during a time-course of activation in culture. Furthermore, this decrease in expression correlated with the increasing expression of MyoD, which is upregulated in activated satellite cells, indicating a potential role for the Klf genes in the regulation of satellite cell quiescence.