Gene regulatory networks (GRNs) provide a systems-level orchestration of an organism's genome encoded anatomy. As biological networks are revealed, they continue to answer many questions including knowledge of how GRNs control morphogenetic movements and how GRNs evolve. The migration of the small micromeres to the coelomic pouches in the sea urchin embryo provides an exceptional model for unde...

base. The anterior cranial base shows an abnormal differentiation of chondrocytes in the mutant, with reduced proliferation and increased terminal differentiation. The main factors responsible to restrict Six2 function to the anterior portion of the cranial base are the tissue-specific transcription of the gene and the presence of compensatory effects from other Six family members, in particula...

Separating digestive and urinary outlets is a critical step during mammalian embryogenesis. However, the natural history of these structures is poorly studied, and little is known about their embryonic origin. Here, we show that peri-cloacal mesenchymal (PCM) progenitors are the major source of these structures. Surprisingly, PCM progenitors also contribute to perineum, a structural barrier sep...

base. The anterior cranial base shows an abnormal differentiation of chondrocytes in the mutant, with reduced proliferation and increased terminal differentiation. The main factors responsible to restrict Six2 function to the anterior portion of the cranial base are the tissue-specific transcription of the gene and the presence of compensatory effects from other Six family members, in particula...

base. The anterior cranial base shows an abnormal differentiation of chondrocytes in the mutant, with reduced proliferation and increased terminal differentiation. The main factors responsible to restrict Six2 function to the anterior portion of the cranial base are the tissue-specific transcription of the gene and the presence of compensatory effects from other Six family members, in particula...