Rostrocaudal polarity formation of chick optic tectum

H Nakamura, N Itasaki, T Matsuno

Research output: Contribution to journalArticle (Academic Journal)peer-review

14 Citations (Scopus)
60 Downloads (Pure)

Abstract

The optic tectum receives retinal fibers in a topographically ordered manner. For the formation of the precise connections, the tectum is believed to be positionally specified by gradients of molecules along axes. Rostrocaudal polarity of the tectum is first detectable at embryonic day 2 (E2) in the chick, by the caudorostral gradient of en expression, then by the rostrocaudal gradient of cytoarchitectonic development. Tectum rotation experiments showed that tectum rostrocaudal polarity is not determined at around 10-somite stage, but is fixed on E3. Ectopic tectum was produced in the diencephalon by transplanting the mesencephalic alar plate heterotopically. In the ectopic tectum, en expression was weakest at the caudal (nearest to the host diencephalo-mesencephalon junction) and strongest at the rostral end. Consequently, the pattern of en expression in the host and ectopic tecta was nearly a mirror image. Retinal fibers projected to the ectopic tectum in a topographic order in accordance with the inverted gradient of the en expression pattern. Ectopic tecta was also produced by heterochronal transplantations between E3 host and E2 donor, where the en pattern was preserved. Retinotectal projection pattern was also preserved, suggesting that en expression patterns are followed by retinotopic order with regard to rostrocaudal polarity.

Original languageEnglish
Pages (from-to)281-6
Number of pages6
JournalInternational Journal of Developmental Biology
Volume38
Issue number2
Publication statusPublished - Jun 1994

Keywords

  • Animals
  • Chick Embryo
  • Gene Expression Regulation, Developmental
  • Genes, Homeobox
  • Neural Pathways
  • Retina
  • Superior Colliculi
  • Time Factors
  • Transplantation, Heterotopic

Fingerprint

Dive into the research topics of 'Rostrocaudal polarity formation of chick optic tectum'. Together they form a unique fingerprint.

Cite this