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A multiphasic role for Pax7 in tectal development.

Meghan Thomas·Lyn Beazley·Melanie Ziman
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Abstract

The optic tectum differentiates from the mesencephalic alar plate and matures into a characteristically laminated structure. Evidence presented here suggests a role for Pax7 in all stages of development of tectal architecture, from regionalisation to specification of neurons and tectal topography. Analysis of Pax7 expression profiles over a range of developmental stages (E2-E12) suggests a biphasic role for Pax7: initially Pax7 expressing cells in the proliferative neuroepithelial layer establish tectal polarity whereas later Pax7 is expressed in neurons of the retino-recipient precursor stratum griseum et fibrosum superficiale (sgfs) laminae where graded levels may establish tectal topography. Furthermore, co-localisation immunofluorescence confirmed that Pax7 is initially expressed in the majority of proliferative neuroepithelial cells and later in a subset of neurons of the sgfs laminae.

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Age FactorsAnimalsChick EmbryoCritical Period, PsychologicalGene Expression Regulation, DevelopmentalNeuroepithelial CellsNeuronsPAX7 Transcription FactorSuperior ColliculiJournal Article

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Meghan Thomas, Lyn Beazley, Melanie Ziman. 2006-01-21. A multiphasic role for Pax7 in tectal development.. https://doi.org/10.1007/s00221-005-0335-0

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