| Research Abstract |
The fresh water coelenterate, Hydra, responds to reduced glutathione to yield the feeding response. When Hydra japonica is cultured in a specific medium, the feeding response is the tentacle ball formation which is sensitively modulated by growth factors from mammalian animals. The response is composed of at least 5 components (R1-R5) on the basis of the modulation by growth factors. Monoclonal antibodies (mAb) which modulated the specific subset of the response were prepared. With use of two mAbs J245 and J5 among these mAbs, both of which depressed R5, the antigen was analyzed in detail to disclose molecular mechanism of the response. When these two mAbs were applied at the same time, the depression on R5 was the same as each mAb was applied separately within an experimental error, implying that these two mAbs has an effect on the same receptor responsible for R5. After labeling the antigen with a photoaffinity ligand of [35S]-glutathione, the labeled antigen was about 200 kDa on a HPLC gel permeation chromatography. When the J245 antigen was analyzed with J5 on the protein blotting, 180, 200 kDa components were common protein of these two mAbs. These results strongly suggest that these proteins, common antigen of J245 and J5, are one of the receptors mediating R5 response.
|
