• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.301.2-301
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• 1997

No Abstract, See Full Text

• Molecules and Cells
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• v.44 no.10
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• pp.723-735
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• 2021

Spemann organizer is a center of dorsal mesoderm and itself retains the mesoderm character, but it has a stimulatory role for neighboring ectoderm cells in becoming neuroectoderm in gastrula embryos. Goosecoid (Gsc) overexpression in ventral region promotes secondary axis formation including neural tissues, but the role of gsc in neural specification could be indirect. We examined the neural inhibitory and stimulatory roles of gsc in the same cell and neighboring cells contexts. In the animal cap explant system, Gsc overexpression inhibited expression of neural specific genes including foxd4l1.1, zic3, ncam, and neurod. Genome-wide chromatin immunoprecipitation sequencing (ChIP-seq) and promoter analysis of early neural genes of foxd4l1.1 and zic3 were performed to show that the neural inhibitory mode of gsc was direct. Site-directed mutagenesis and serially deleted construct studies of foxd4l1.1 promoter revealed that Gsc directly binds within the foxd4l1.1 promoter to repress its expression. Conjugation assay of animal cap explants was also performed to demonstrate an indirect neural stimulatory role for gsc. The genes for secretory molecules, Chordin and Noggin, were up-regulated in gsc injected cells with the neural fate only achieved in gsc uninjected neighboring cells. These experiments suggested that gsc regulates neuroectoderm formation negatively when expressed in the same cell and positively in neighboring cells via soluble factors. One is a direct suppressive circuit of neural genes in gsc expressing mesoderm cells and the other is an indirect stimulatory circuit for neurogenesis in neighboring ectoderm cells via secreted BMP antagonizers.

• Animal cells and systems
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• v.12 no.4
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• pp.219-230
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• 2008

We are reporting the expression patterns and possible biological functions of a novel Kinesin-like protein, Surhe, in the zebrafish. Homology studies of derived amino acid sequences suggest that Surhe has an amino-terminal kinesin motor domain that is similar to that of the emerging MKLP-1 subfamily [Kim and Endow, 2000] and two coiledcoil domains in a central region. Cellular localization studies in mammalian cells revealed that Surhe protein is located in cytoplasm, suggesting that Surhe may be involved in the intracellular transport. During the developmental process, surhe transcripts are highly expressed in early embryonic stages. Overexpression of the dominant negative form of Surhe significantly down-regulates the dorsalization markers, such as goosecoid, bozozok, and chordin. Taken together, we postulate that Surhe may be involved in dorsalization process as a motor molecule.