• Journal of Photoscience
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• 제9권2호
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• pp.278-280
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• 2002

We have cloned a hydromedusan opsin cDNA and showed that the deduced amino acid sequence of the cytoplasmic loop between helices 5 and 6 (loop 5-6) was clearly different from that reported so far. The amino acid sequence of the loop 5-6 is important on determination of the specificity for the coupled G- protein. To clarify which class of G-protein mediates the phototransduction system in the ocellus of the hydromedusan, we investigated G-proteins expressed in the ocellus. By PCR against the cDNA of the ocellus with primers designed according to the conserved amino acid sequence in G-protein a subunit, we obtained three kinds of cDNA fragments. Based on the sequence similarities, ttwo of them (JGI and JG3) were classified as $G_{i}$ and $G_{q}$, respectively. The other one (JG2) was a new subtype within $G_{*}$ class. Electron microscopic immunocytochemistry with the antiserum against the C-terminal sequence of $G_{q}$ or $G_{t}$ revealed the presence. of the both classes in the ocellus. The similarity of the C-terminal sequence of the JG2 with that of bovine $G_{t}$ suggests that the anti- $G_{t}$ antiserum would bind to JG2. These results suggest the possibility that the hydromedusan rhodopsin decides the specificity for the coupled G-protein by the other domain than the loop 5-6.oop 5-6.5-6.

• Animal Systematics, Evolution and Diversity
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• 제20권1호
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• pp.31-37
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• 2004

서귀포(제주도),, 횡간도 및 일산해수욕장(울산)에서 1985년 7월 11일, 1990년 7월 23일 1994 년 7월 16일에 채집된 히드라해파리류는 평면해파리(Aequorea coerulescens)와 작은부레관해파리(Physalia physalis utriculus)로 각각 동정되었다. 이들은 한국 미기록종으로 판명되어 재기재하여 보고한다. 평면해파리는 외산이 편평한 베레모 모양이고 큰 입을 가지며 60개의 주름진 구엽과 120개의 방사관을 가진다. 작은부레관해파리는 비교적 큰 부유기를 가지고 부유기의 아래에 섭식개충, 지상개충(=방어개충), 생식개충과 1개의 리본 모양의 큰 주촉수와 많은 작은 촉수를 가진다. 본 연구의 결과 지금까지 밝혀진 한국 해산 히드라해파리류는 5목 13과 15종이 된다.