• Journal of Plant Biology
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• 제38권1호
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• pp.87-93
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• 1995

최근에 Synechocystis sp. PCC 6803 중에 한 균주가 고체 한천 배지상에서 일정한 조명(300-1000 lux) 방향을 따라 활주 운동하는 것을 관찰하여 이 종을 S. 6803 PTX라고 명명하고 이의 주광성 운동에 대한 생리학적 특징을 이해하기 위하여 몇 가지 대사 억제제와 신호 전달 차단제의 주광성 운동에 미치는 효과를 조사하였다. DCMU는 광계 II로부터 광계 I의 일차 전자 수용체인 플라스토퀴논으로의 비순환성 광합성 전자전달을 억제하는 억제자로서 $100\;\mu\textrm{M}$의 농도에서는 주광성 운동을 억제하지 못하였다. 그러나 호흡에 의한 전자전달 억제제인 sodium azide를 처리하였을 경우에는 S. 6803 PTX에서 심하게 장해를 받았다. 이러한 관찰 결과는 주광성 운동의 주동력원이 광인산화 과정보다는 호흡에 의한 산화적인 인산화과정에 주로 연관되어 있음을 보여주었다. 또한, 세포를 CCCP나 DNP와 같은 막상의 uncoupler를 처리하였을 때, 세포내 ATP 농도를 저하시키거나 세포질막에 수소 이온의 전기화학구배($\Delta\mu_{H}+$)를 제거시키나, 이러한 화합물들은 주광성 운동에 뚜렷한 영향은 주지 못하였다. 이러한 결과와는 달리, H+-F0F1 ATPase에 민감하게 억제 작용을 나타내는 DCCD나 NBD의 처리는 세포내 ATP만 고갈시키고 막상에서 $\Delta\mu_{H}+$는 그대로 유지시키는 작용을 하는데, 이러한 DCCD나 NBD는 주광성 운동에 대해서는 심하게 억제 현상을 나타내었다. 또한, 특이성 calcium ionophore 중의 하나인 A23187의 처리는 양성 주광성에 심하게 장해를 주었다. 아마도 Ca2+ 유동은 주광운동 방향성의 신호전달 과정에 중요하게 관련되어 있는 것으로 나타났다. 마지막으로 S-adenosyl methionine과 같은 메틸 공여체의 고갈이 S. 6803 PTX 균주의 주광성 반응에 영향을 주는지를 알아보기 위하여 에티오닌을 BG11을 한천 배지에 첨가하였다. 이 생물종의 광운동은 에티오닌의 농도가 증가됨에 따라 일정하게 억제되다가 0.5mM에서 주광성 운동을 완전히 억제시켰다. 이것은 광수용 기작이 Escherichia coil나 Salmonella typhimurium에서 발견된 메틸기 수용 주화성 단백질과 같은 메틸화/탈메틸화 과정에 의하여 조절될 가능성을 보여주고 있음을 의미한다.

• 한국동물학회지
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• 제20권1호
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• pp.1-8
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• 1977

1974年 安養에서 採集한 초파리의 走光性行動에 대한 人爲淘汰實驗을 행하였다. 淘汰의 結果, 第10世代까지의 走光性 및 避光系統의 遺傳率은 每世代當 2$\\sim$4%로 나타났다. 淘汰系統間의 相對交配實驗의 結果, 避光行動을 나타내는 遺傳子가 走光性遺傳子에 대하여 部分的 優性의 효과가 있음을 알았고, 그 효과는 淘汰의 後期世代에서 더욱 뚜렷하였다. 淘汰15世代後, 走光性과 避光性系統에 대하여 人爲淘汰를 中止하고 自然淘汰에 의한 遺傳子의 行動을 調査하였다. 實驗結果, 數世代以內에 最初集團의 走光性指數로 환원되었다. 이러한 현상은 自然淘汰에 의한 遺傳的復元性의 一例라고 생각된다.

• Journal of Photoscience
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• 제9권2호
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• pp.287-289
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• 2002

Planarians show negative phototaxis and have extensive regenerative ability, including the ability to regenerate the brain. Recently the process of regeneration of the planarian brain has been divided into three steps based on the expression of neural markers. In this study, we have analyzed the process of recovery of the light response during head regeneration. Although morphological observations indicated that regeneration of the eyes and optic nerves appeared to be completed by the fourth day, the recovery of the evasion behavior against light was not recovered within 4 days after amputation. Functional recovery of the evasion behavior could be detected starting 5 days after amputation and then gradually recovered. We previously identified genes which are specifically expressed in the brain after the recovery of morphological structures. This characteristic suggested that these genes may be involved in functional recovery of the brain. To investigate the function of these genes, we performed gene knockout analysis using the RNA interference method. The results clearly indicated that these genes are involved in the functional recovery of the visual system.

• 한국광과학회:학술대회논문집
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• 한국광과학회 2005년도 제12회 학술대회 논문초록
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• pp.110-110
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• 2005

• 한국동물생명공학회지
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• 제35권3호
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• pp.245-257
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• 2020

Behavioral response to a diel photoperiodicity (500 lx for 16 h, 5 lx for 4 h and < 0.5 lx for 4 h) and phototactic characteristics in dark conditions were examined with Siberian sturgeon Acipenser baerii (Chondrostei, Actinopterygii) prelarvae. Siberian sturgeon prelarvae represented both qualitative and quantitative changes in their behavioral patterns according to different light intensities in a diel photoperiodicity. Under daylight conditions (500 lx), prelarvae displayed saltatory changes of behavioral features with ages (Day 0-Day 9) in a general order of swimming-up/drifting, swimming in the upper water column, benthic swimming with rheotaxis, schooling and post-schooling behavior. Compared to daylight conditions, prelarvae tended to show more benthic performances and quantitative reductions of schooling and post-schooling behaviors under dimlight conditions (5 lx). Under dark conditions (< 0.5 lx), prelarvae exhibited a fairly uniform behavioral pattern characterized by the benthic swimming across the bottom of the tank. From phototaxis tests under dark conditions, navigational responses of prelarvae to a spotlight illumination were quantitatively changed as their ages increased. The phototactic responses reached the peak on Day 2, continued until Day 4, and then gradually decreased until Day 8. A partial recovery of positive phototaxis was observed on Day 9. Data from this study suggest that the diel light cycle as well as the light intensity of each interval in the cycle should be considered as important components of a practical guide for evaluating fitness and developmental states of artificially propagated Siberian sturgeon prelarvae.

• 한국광과학회:학술대회논문집
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• 한국광과학회 1999년도 학술대회지
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• pp.108-108
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• 1999

• 한국수산과학회지
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• 제12권2호
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• pp.79-86
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• 1979

빛이 어류의 행동에 미치는 영향을 조사하기 위하여 잉어, Cyprinus carpio에 광척극을 가한 실험을 낮과 밤에 각각 실시한 결과를 요약하면 다음과 같다. 1. 잉어의 분포율은 본 실험에 사용한 제한된 수조내에서 U자형과 거의 같은 구간분포경향을 보였다. 2. 빛의 세기가 어떤 적정치보다 더 강하거나 약할 때 어류가 광원으로부터 멀리 떨어진 곳에 모였기 때문에 잉어의 적정수중조도가 발견되었다. 3. 수중조도에 대한 집어율곡선의 최대치로부터 잉어의 집어율이 낮과 밤에 차이가 있었다. 4. 잉어의 집어율이 최대인 평균수중조도는 낮에 $3.813lux(2.99\~4.761\;lux)$였고, 밤에는 $6.292lux(5.0\~7.89\;lux)$였다. 5. 잉어의 집어율은 반사집어율과 평형집어율의 두가지 형태로 나타났다. 6. 반사집어율은 광원을 점등한 직후에 나타났으며, 시간에 따라 변화를 보였고, 평형집어율은 거의 균일하였다.

• Journal of Photoscience
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• 제11권3호
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• pp.89-94
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• 2004

Motile cyanobacterium Synechocystis sp. PCC 6803 cells show photomovement with respect to the light stimulus. Under lateral irradiation, Synechocystis displays a phototactic gliding movement toward the light source by a twodimensional random biased walk. Under vertical irradiation, Synechocystis decreased the frequency of mean vectorial gliding speed dependent on the applied fluence rate, whereas the deviation distribution width of the speed increased. This strongly suggests the involvement of photokinesis. Evidence for the cyanobacterial photokinesis was discussed in the previous report (Choi et al., 1999. Photochem. Photobiol. 70, 95-102) demonstrating that the gross scalar speed of vertically irradiating cells increased by about 50% compared with that of dark-adapted cells. In the visible wavelength range, Synechocystis cells showed a maximal photokinetic activity at 420 nm and a second maximal activity at 680 nm. The threshold action spectrum for the photokinesis resembles the absorption spectrum of chlorophyll with major differences in the phototaxis action spectrum at 560 nm and 660 nm. We postulate that the cyanobacterial photokinesis is powered by the energy-generating chlorophyll pigments.

• 한국수산과학회지
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• 제52권3호
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• pp.274-282
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• 2019

Female Siberian sturgeon Acipenser baerii were crossed with male Russian sturgeon A. gueldenstaedtii and the development, ontogenetic behavior, and phototactic characteristics of the resultant hybrid prolarvae were examined. The fertilization rate of the hybrid group was similar to that of Siberian sturgeon (the maternal species), and the overall developmental characteristics of hybrid embryos were not significantly different from those of either parental species. The time window from first hatch to the completion of hatching was wider in Russian sturgeon than in Siberian and hybrid sturgeon groups. The prolarval viability of the hybrid group was similar to that of the maternal species, and significantly higher than that of the paternal species. Hybrid prolarvae displayed ontogenetic behavioral patterns that were quite similar to those of Siberian sturgeon. In an illumination preference test, hybrid prolarvae displayed significant positive phototaxis, similar to the maternal species, and clearly distinct from the negative phototactic character of the paternal species. Taken together, our data indicate that the prolarval traits of hybrid sturgeon from this cross more closely resemble those of the maternal than the paternal species.

• Fisheries and Aquatic Sciences
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• 제22권1호
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• pp.4.1-4.10
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• 2019

Russian sturgeon (Acipenser gueldenstaedtii) is commercially important in Korea because its caviar is highly prized. Although the early ontogeny of the species has been described, behavioral modifications in response to various light intensities or diel photoperiodicity patterns have not been studied extensively. The objective of the present study was to examine the behavioral characteristics of hatchery-produced A. gueldenstaedtii prelarvae over a diel photoperiodic cycle. During a diel light cycle comprising 16 h of daylight (450 lx), 4 h of dim light (10 lx), and 4 h of darkness (< 1 lx), newly hatched A. gueldenstaedtii prelarvae exhibited negative phototaxis in daylight (day 0-day 2), and this early behavior was not significantly affected by changes of light intensities. Rheotactic and non-rheotactic aggregation into schools was typical between days 3 and 6. Under the diel light cycle conditions described, rheotaxis was not influenced by environmental light intensity as much as non-rheotactic schooling behavior. Post-schooling behavior, which progressed from day 7 to day 8, did not change significantly during the diel light cycle. The data from the present study could be of practical value in developing a visual guide for assessing the fitness and quality of Russian sturgeon prelarvae under diel light cycle conditions in hatcheries.