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NASA NTRS · 20040113680

Conservation of Pax gene expression in ectodermal placodes of the lamprey

McCauley, David W.·Bronner-Fraser, Marianne
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Abstract

Ectodermal placodes contribute to the cranial ganglia and sense organs of the head and, together with neural crest cells, represent defining features of the vertebrate embryo. The identity of different placodes appears to be specified in part by the expression of different Pax genes, with Pax-3/7 class genes being expressed in the trigeminal placode of mice, chick, frogs and fish, and Pax-2/5/8 class genes expressed in the otic placode. Here, we present the cloning and expression pattern of lamprey Pax-7 and Pax-2, which mark the trigeminal and otic placodes, respectively, as well as other structures characteristic of vertebrate Pax genes. These results suggest conservation of Pax genes and placodal structures in basal and derived vertebrates.

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NASA Discipline Evolutionary BiologyNon-NASA CenterEctoderm/metabolismLampreys/embryology/geneticsDNA-Binding Proteins/geneticsTranscription Factors/geneticsHomeodomain Proteins/geneticsMultigene Family/geneticsCloning, MolecularSequence Homology, Nucleic AcidAnimalsSequence AlignmentSupport, U.S. Gov't, Non-P.H.SDNA, Complementary/chemistry/geneticsBase SequenceMolecular Sequence DataAmino Acid SequenceSequence Homology, Amino AcidIn Situ HybridizationComparative StudyGene Expression Regulation, DevelopmentalSequence Analysis, DNAPhylogenyConserved Sequence/geneticsEmbryo, Nonmammalian/growth & development/metabolism

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McCauley, David W., Bronner-Fraser, Marianne. 2002-04-03. Conservation of Pax gene expression in ectodermal placodes of the lamprey. https://ntrs.nasa.gov/citations/20040113680

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