Text: Transcriptome of the visual cortex in WT or Chrdl1 KO mice at post-natal day 14. Chrdl1, a BMP antagonist, is an astrocyte-secreted factor that promotes synapse maturation in the upper layers of the visual cortex at P14. We analyzed the transcriptome of the visual cortex of WT and Chrdl1 KO mice at P14 in order to determine if genes related to BMP signaling, astrocyte development or synapse formation were altered. RNA was isolated from visual cortex of WT or KO mice at post-natal day 14.
Question: Extract the cell lines mentioned in the above texts and return None if there are no cell lines mentioned. In your entire response, the letter n should appear less than 26.
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