Differential expression of Islet-1 in neural crest-derived ganglia: Islet-1+dorsal root ganglion cells are post-mitotic and Islet-1+sympathetic ganglion cells are still cycling

The Islet-l antigen is an early marker of differentiation of neural tube ce lls, and is expressed in many other embryonic cells as well. It had been re ported that Islet-l is expressed only in post-mitotic sympathetic neuroblas ts in vitro, unlike other differentiation markers. We have double-labeled S t. 23 chick embryos for bromodeoxyuridine (BrDU) and Islet-l and found that neural tube and dorsal root ganglion (DRG) cells express Islet-l after lea ving the cell cycle, while sympathetic ganglion (SG) cells express Islet-l while still dividing. (C) 1999 Elsevier Science B.V. All rights reserved.