Downstream effector of Rap required for cell adhesion and migration of neural crest precursors during development. Interacts with RAP1A; in a GTP-dependent manner. Ubiquitously expressed and enriched in the anterior part of the embryos. Present at very low level in one-cell embryos, suggesting the presence of maternally deposited transcripts. Increases upon the onset of zygotic transcription (around the 1000-cell stage), eventually peaking at 72 hpf. Knockdown results in multiple defects in neural crest-derived lineages such as cartilage, pigment cells, and enteric neurons. Belongs to the RADIL family.