著者

Mukai Takahiko Sato Torao Naruse Kiyoshi Inaba Kazuo Shima Akihiro Morisawa Masaaki

出版者

社団法人日本動物学会

雑誌

Zoological science (ISSN:02890003)

巻号頁・発行日

vol.13, no.1, pp.175-183, 1996-02-15

被引用文献数

1

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The genetic relationships and taxonomic status of 7 taxa belonging to the genus Tridentiger (Pisces, Gobiidae) were investigated by means of analysis of allozymic variation at 14 loci. The results suggest that the two taxa "T. obscurus" and "T. brevispinis" which are sympatric and morphologically similar are reproductively isolated and are highly divergent from each other (the genetic distance values are 0.501-0.707). It is also suggested that "T. brevispinis" and "T. kuroiwae" are genetically different enough from each other to deserve subspecies at least. The other 4 taxa, "T. barbatus", "T. nudicervicus", "T. trigonocephalus" and "T. bifasciatus", are genetically divergent each and are considered to be 4 biological species. A dendrogram showing the phylogenetic relationships of the 7 taxa was constructed from the genetic distances.

著者

Yaguchi Shunsuke Yaguchi Junko Zheng Wei Jin Yinhua Angerer Lynne M. Inaba Kazuo

出版者

the Company of Biologists Ltd.

雑誌

Development (ISSN:09501991)

巻号頁・発行日

vol.138, no.19, pp.4233-4243, 2011-10

被引用文献数

36 10

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Partitioning ectoderm precisely into neurogenic and non-neurogenic regions is an essential step for neurogenesis of almost all bilaterian embryos. Although it is widely accepted that antagonism between BMP and its inhibitors primarily sets up the border between these two types of ectoderm, it is unclear how such extracellular, diffusible molecules create a sharp and precise border at the single-cell level. Here, we show that Fez, a zinc finger protein, functions as an intracellular factor attenuating BMP signaling specifically within the neurogenic region at the anterior end of sea urchin embryos, termed the animal plate. When Fez function is blocked, the size of this neurogenic ectoderm becomes smaller than normal. However, this reduction is rescued in Fez morphants simply by blocking BMP2/4 translation, indicating that Fez maintains the size of the animal plate by attenuating BMP2/4 function. Consistent with this, the gradient of BMP activity along the aboral side of the animal plate, as measured by pSmad1/5/8 levels, drops significantly in cells expressing Fez and this steep decline requires Fez function. Our data reveal that this neurogenic ectoderm produces an intrinsic system that attenuates BMP signaling to ensure the establishment of a stable, well-defined neural territory, the animal plate.