Exp Neurobiol 2003; 12(1): 57-64
Published online July 1, 2003
© The Korean Society for Brain and Neural Sciences
Jeong-Sun Choi, Hyun-Jung Park and Mun-Yong Lee*
Department of Anatomy, College of Medicine, The Catholic University of Korea, Seoul, Korea
Correspondence to: *To whom correspondence should be addressed.
TEL: 82-2-590-1108, FAX: 82-2-536-3110
Recently, an increasing body of evidence has identified Phospholipase D (PLD), one of the intracellular signal transduction enzymes to be involved in the proliferation and differentiation of neurons in the developing brain. The present study has further characterized the cellular and temporal localization of the PLD1 protein, using immunohistochemistry, in the embryonic rat brain. The phenotype of PLD1-expressing cells was investigated using double labeling with a migrating neuroblast marker, doublecortin (DCX), and a neural stem cell marker, nestin. The neuronal expression of PLD1 was first observed in the germinal neuroepithelium of the lateral and third ventricles in the E15 brain, and persisted in the all ventricles throughout brain development of embryonic stages. In addition, PLD1 was expressed by neurons that appeared to be migrating both radially and nonradially, indicating that many of them could be migrating neuroblasts. The morphology and spatiotemporal distribution pattern of PLD1 immunoreactive cells were compared with those of cells expressing nestin or DCX in adjacent sections, and double-labeling studies demonstrated the co-expression of DCX or nestin in most of the PLD1 immunoreactive cells. Therefore, our findings provide evidence that PLD1 is transiently expressed in selected ventricular zones and apparently migrating cells in embryonic rat brains, suggesting that PLD1 may be involved in early developmental processes, such as the proliferation, migration and differentiation of some neuronal populations.
Keywords: PLD1, ventricular zone, nestin, doublecortin, development, differentiation, immunohistochemistry