1993 Fiscal Year Final Research Report Summary
Study on the regulation of a gene expressed solely in embryonic stage
| Project/Area Number |
03454022
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
動物発生・生理学
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| Research Institution | Tokyo Metoropolitan University |
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Principal Investigator |
YASUGI Sadao Tokyo Metoropol. Univ., Fac. Science, Prof., 理学部, 教授 (70011591)
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| Project Period (FY) |
1991 – 1993
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| Keywords | Regulation of gene expression / Pepsinogen gene / Epithelial-mesenchymal interactions / Stomach epithelial cells / DNA methylation |
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| Research Abstract |
The aim of the present study is to elucidate the regulation mechanisms of gene expression restricted spacio-temporally during the course of animal embryogenesis. We tried to reveal the regulation mechanisms of expression of embryonic chicken pepsinogen (ECPg), which is known to be expressed only in the epithelial cell of embryonic proventriculus. The main results obtained can be summarized as follows :
(1) The experimental embryological studies showed that epithelial cells of esophagus, proventriculus and gizzard of have potency to express ECPg under appropriate conditions and inhibitory influences of esophageal and gizzard mesenchymes ensure the restricted expression of ECPg gene in the normal course of development. Also, the expression of a sort of keratin molecule is regulated by the action of the mesenchyme. (2) The demethylation of DNA of ECPg gene is involved in the organ-specific expression of the gene. (3) We demonstrated that the influences of proventricular and gizzard mesenchymes are mediated to the expression of ECPg gene via the l kb sequence of 5' region of the gene.
From the above mentioned results, we can now conceive a scenario leading to the restricted expression of ECPg gene. In the early period of development, the endoderm composing the digestive tract is divided into two parts, with regard to the potency express ECPg gene. The realization of ECPg expression thereafter is brought about by fine turning of the mesenchymal influences. The dementhylation of ECPg gene can be thought as a kind of double assurance. The identification of trans-acting factors which bind to the 5' region of ECPg gene and the regulation of expression of these factors by mesenchymal influences will be important problems in future.
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