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Amphioxus and lamprey AP-2 genes: implications for neural crest evolution and migration patterns.

Daniel Meulemans·Marianne Bronner-Fraser
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Abstract

The neural crest is a uniquely vertebrate cell type present in the most basal vertebrates, but not in cephalochordates. We have studied differences in regulation of the neural crest marker AP-2 across two evolutionary transitions: invertebrate to vertebrate, and agnathan to gnathostome. Isolation and comparison of amphioxus, lamprey and axolotl AP-2 reveals its extensive expansion in the vertebrate dorsal neural tube and pharyngeal arches, implying co-option of AP-2 genes by neural crest cells early in vertebrate evolution. Expression in non-neural ectoderm is a conserved feature in amphioxus and vertebrates, suggesting an ancient role for AP-2 genes in this tissue. There is also common expression in subsets of ventrolateral neurons in the anterior neural tube, consistent with a primitive role in brain development. Comparison of AP-2 expression in axolotl and lamprey suggests an elaboration of cranial neural crest patterning in gnathostomes. However, migration of AP-2-expressing neural crest cells medial to the pharyngeal arch mesoderm appears to be a primitive feature retained in all vertebrates. Because AP-2 has essential roles in cranial neural crest differentiation and proliferation, the co-option of AP-2 by neural crest cells in the vertebrate lineage was a potentially crucial event in vertebrate evolution.

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AmbystomaAmino Acid SequenceAnimalsBase SequenceBody PatterningCell MovementChordata, NonvertebrateDNA, ComplementaryDNA-Binding ProteinsEvolution, MolecularGene Expression Regulation, DevelopmentalLampreysMolecular Sequence DataNeural CrestPhylogenySequence Homology, Amino AcidSpecies SpecificityTranscription Factor AP-2Transcription FactorsNASA Discipline Evolutionary BiologyNon-NASA CenterComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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Daniel Meulemans, Marianne Bronner-Fraser. 2002. Amphioxus and lamprey AP-2 genes: implications for neural crest evolution and migration patterns.. https://doi.org/10.1242/dev.129.21.4953

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