Control of chick tectum territory along dorsoventral axis by Sonic hedgehog

DOI PDF PubMed 被引用文献4件
  • Yuji Watanabe
    Department of Molecular Neurobiology, Institute of Development, Aging and Cancer, Tohoku University, Aoba-ku, Sendai 980-8575, Japan
  • Harukazu Nakamura
    Department of Molecular Neurobiology, Institute of Development, Aging and Cancer, Tohoku University, Aoba-ku, Sendai 980-8575, Japan

書誌事項

公開日
2000-03-01
権利情報
  • http://www.biologists.com/user-licence-1-1/
DOI
  • 10.1242/dev.127.5.1131
公開者
The Company of Biologists

この論文をさがす

説明

<jats:title>ABSTRACT</jats:title> <jats:p>Chick midbrain comprises two major components along the dorsoventral axis, the tectum and the tegmentum. The alar plate differentiates into the optic tectum, while the basal plate gives rise to the tegmentum. It is largely unknown how the differences between these two structures are molecularly controlled during the midbrain development. The secreted protein Sonic hedgehog (Shh) produced in the notochord and floor plate induces differentiation of ventral cell types of the central nervous system. To evaluate the role of Shh in the establishment of dorsoventral polarity in the developing midbrain, we have ectopically expressed Shh unilaterally in the brain vesicles including whole midbrain of E1.5 chick embryos in ovo. Ectopic Shh repressed normal growth of the tectum, producing dorsally enlarged tegmentum region. In addition, the expression of several genes crucial for tectum formation was strongly suppressed in the midbrain and isthmus. Markers for midbrain roof plate were inhibited, indicating that the roof plate was not fully generated. After E5, the tectum territory of Shh-transfected side was significantly reduced and was fused with that of untransfected side. Moreover, ectopic Shh induced a considerable number of SC1-positive motor neurons, overlapping markers such as HNF-3β (floor plate), Isl-1 (postmitotic motor neuron) and Lim1/2. Dopaminergic and serotonergic neurons were also generated in the dorsally extended region. These changes indicate that ectopic Shh changed the fate of the mesencephalic alar plate to that of the basal plate, suppressing the massive cell proliferation that normally occurs in the developing tectum. Taken together our results suggest that Shh signaling restricts the tectum territory by controlling the molecular cascade for tectum formation along dorsoventral axis and by regulating neuronal cell diversity in the ventral midbrain.</jats:p>

収録刊行物

  • Development

    Development 127 (5), 1131-1140, 2000-03-01

    The Company of Biologists

被引用文献 (4)*注記

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ