RhoB is expressed in migrating neural crest and endocardial cushions of the developing mouse embryo

RhoB mRNA expression was examined in the developing mouse embryo between E8 .5 and E11.5. Specific expression was found in migrating neural crest (NC) cells, from the first stages of their migration at E9.5, throughout the mig ration period. Expression is maintained in NC derivatives for at least one embryonic day after they reach their final destinations, but is then down-r egulated. RhoB is also expressed in non NC-derived neural tissues, includin g motor neurones and the floor plate of the neural tube. RhoB mRNA expressi on is also found in the developing endocardial cushions of the atrioventric ular and outflow regions of the developing heart. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.