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Sumihare Noji

Publications and source records attributed to Sumihare Noji.

39 records · Page 3Linked to original sources

FGF10 is a mesenchymally derived stimulator for epidermal development in the chick embryonic skin.

The development of avian cutaneous appendages, feathers and scales, is known to arise from the epithelial-mesenchymal interaction. Here we show that FGF10 is associated with this developmental process as an early signal from mesenchymal cells underlying nascent cutaneous placodes. Expression of Fgf10 was detected in the mesenchymal cells underneath the developing placodes. Forced expression of Fgf10 in the femoral skin suppressed expression of Shh and a zinc finger gene snail-related (cSnR), while induced expression of Bmp2 in the interbud region, resulting in thickening of the epidermal layer. Furthermore, forced expression of Fgf10 in the foot skin caused marked ingrowings of the epidermis. The cells in the epidermal ingrowings expressed beta-catenin, proliferating cell nuclear antigen, and an epidermal stem cell marker p63. These results support the idea that FGF10 is a mesenchymally derived stimulator of epidermal development through crosstalk with bone morphogenetic protein (BMP), beta-catenin, and other signaling pathways.

Animals↗

Extrachromosomal transposition of the transposable element Minos in embryos of the cricket Gryllus bimaculatus.

Effective germline transformation of insects has been shown to depend on the right choice of transposon system and selection marker. In this study the promoter region of a Gryllus cytoplasmic actin (GbA3/4) gene was isolated and characterized, and was used to drive the expression of Minos transposase in embryos of the cricket Gryllus bimaculatus. Active Minos transposase was produced in these embryos as monitored through established transposon excision and interplasmid transposition assays. In contrast, Drosophila melanogaster hsp70 promoter, previously used to express Minos transposase in a number of insect species and insect cell lines, failed to produce any detectable Minos transposase activity, as recorded by using the very sensitive transposon excision assay. In addition, the GbA3/4 promoter was found to drive expression of enhanced green fluorescent protein (eGFP) predominantly in vitellophages of the developing Gryllus eggs when a plasmid carrying a GbA3/4 promoter-eGFP fusion gene was transiently injected into embryos. These results strongly support the use of Minos transposons marked with the GbA3/4 promoter-eGFP for the genetic transformation of this emerging model insect species.

Actins↗

Identification of cis-elements regulating expression of Fgf10 during limb development.

Fibroblast growth factor 10 (FGF10) is known to be expressed in limb mesenchymal cells and to function as a mesenchymal signaling factor involved in epithelial-mesenchymal interactions during limb development. To elucidate regulation of Fgf10 expression, we isolated the promoter region of Fgf10 containing its 2.0 kb upstream 5'-fragment from the initiation codon and its 0.9 kb downstream fragment. Transcriptional activity of the fragment was examined with transgenic mice, using a lacZ-reporter system. Although no significant expression of the reporter gene was observed for the 0.2 kb 5'-fragment, expression was detected in the apical ectodermal ridge of the limb bud and developing cartilage of the limb for the 2.0 kb and 0.7 kb 5'-fragments, respectively. From comparison of the mouse sequences of the 2.0 kb fragment with corresponding sequences of human and chicken Fgf10, we identified 17 conserved putative enhancer motifs for AER expression and other unidentified expressions. For limb cartilage expression, we found putative enhancer sequences conserved among the three species in the 0.7 kb 5'-fragment. In the fragment, three DNA binding motifs were identified in the mouse and human sequence, although they are not conserved in the corresponding chicken sequence.

Animals↗