1993 Fiscal Year Final Research Report Summary
Roles of Cell Adhesion Molecules in Hydra Development
| Project/Area Number |
04044174
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| Research Category |
Grant-in-Aid for international Scientific Research
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| Allocation Type | Single-year Grants |
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| Section | Joint Research |
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| Research Institution | National Institute of Genetics |
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Principal Investigator |
SUGIYAMA Tsutomu National Institute of Genetics, 個体遺伝研究系, 教授 (40000260)
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| Co-Investigator(Kenkyū-buntansha) |
BODE Hans R. Dept of Developmental and Cell Biology Univ. of California, Irvine., アーバイン校・発生細胞生物学科, 教授
DAVID Charles N. Zoological Institute, Univ. of Munich, 動物学研究所, 教授
HATTA Masayuki National Institute of Genetics, 個体遺伝研究系, 助手 (00249947)
FUJISAWA Toshitaka National Institute of Genetics, 個体遺伝研究系, 助教授 (60000262)
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| Project Period (FY) |
1992 – 1993
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| Keywords | Hydra / Cell adhesion molecule / cadherin / catenin / カテニン |
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| Research Abstract |
PCR approach was used to isolate hydra homologues of cell adhesion molecules and their associated molecules present in vertebrates and insects. Four PCR fragments were obtained. Two correspond to extra cellular repeating domains of cadherin (proto-cadherin), 1 to beta-chain of integrin and 1 to beta-catenin. The AT contents at third codon positions of the 4 fragments are all higher than 65% as in all other hydra genes previously cloned.
A screening of hydra cDNA libraries using these fragments as probes yielded a cDNA clone of hydra beta-Catenin. Putative peptide encoded by the clone has high homology to vertebrate counterparts and a high AT content at third codon position. Screening for other genes are currently in progress.
In another line of study, a functional assay was used to isolate new cell adhesion molecules of hydra. Dissociated hydra cells can reaggregate and eventually regenerate a new polyp. Antisera raised against hydra membrane fraction inhibit reaggregation of dissociated cells. This suggests that the antisera contain an antibody molecule which binds to and blocks the function of the cell adhesion molecule involved in reaggregation.
We attempted to isolated this cell adhesion molecule by its ability to neutralize the inhibitory activity of the antisera. It was found that an extract produced by tryptic digestion of the membrane fraction has the neutralizing activity. The active factor in the tryptic digest has a MW of about 100 KDa. We currently use HLPC to purify this factor (cell adhesion molecule). When isolated, it will be used to isolate the gene encoding it by conventional approaches.
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