WIDESPREAD PROGRAMMED CELL-DEATH IN EARLY DEVELOPING CHICK OPTIC TECTUM

WE demonstrate that widespread programmed cell death exists in prolife rative regions of chicken optic tectum during early development using a sensitive fluorescent ISEL method (FISEL+) and antibody staining for an antigen in dying cells. Several developmental stages from embryoni c day (E) 3 to E18 were examined. FISEL+positive cells were rare befor e E7 and between E9 to E12. However, massive labeling was observed in the ventricular zone (VZ) between stages E7.5 and ES. At this time ext ensive cell migration is underway and many labeled cells were found no t only in the VZ (premigratory cells) but also in the intermediate zon e and tectal plate (migratory cells). Many labeled cells were also fou nd in upper tectal laminae at late developmental stages (E15 and E18). (C) 1998 Lippincott Williams & Wilkins.