• 제목/요약/키워드: Light signaling

검색결과 148건 처리시간 0.022초

Cloning and Expression Characteristics of Pharbitis nil COP1 (PnCOP1) During the Floral Induction

  • 김윤희;김성룡;허윤강
    • Journal of Photoscience
    • /
    • 제12권1호
    • /
    • pp.1-9
    • /
    • 2005
  • The ubiquitin E3 ligase COP1 (Constitutive Photomorphogenesis 1) is a protein repressor of photomorphogenesis in Arabidopsisplants, and it found in various organisms, including animals. The COP1 protein regulates the stability of many of the light-signaling components that are involved in photomorphogenesis and in the developmental processes. To study the effect of COP1 on flowering in a short day plant, we have cloned a full-length of PnCOP1 (Pharbitis nil COP1) cDNA from Pharbitis nil Choisy cv. Violet, and we examined its transcript levels under various conditions. A full-length PnCOP1 cDNA consists of 2,280 bp nucleotidesthat contain 47 bp of 5'-UTR, 232 bp of 3'-UTR including the poly (A) tail, and 1,998 bp of the coding sequence. The deduced amino acid sequence contains 666 amino acids, giving it a theoretical molecular weight of 75 kD and a isolectric point of 6.2. The PnCOP1 contains three distinct domains, an N-terminal $Zn^2+$-binding RING-finger domain, a coiled-coil structure, and WD40 repeats at the C-terminal, implying that the protein plays a role in protein-protein interactions. The PnCOP1 transcript was detected in the cotyledon, hypocotyls and leaves, but not in root. The levels of the PnCOP1 transcript were reduced in leaves that were a farther distance away from the cotyledons. The expression level of the PnCOP1 gene was inhibited by light, while the expression was increased in the dark. During the floral inductive 16 hour-dark period for Pharbitis nil, the expression was increased and it reached its maximum at the 12th hour of the dark period. The levels of PnCOP1 mRNA were dramatically reduced upon light illumination. These results suggest that PnCOP1 may play an important function in the floral induction of Pharbitis nil.

  • PDF

Cell-cell contacts via N-cadherin induce a regulatory renin secretory phenotype in As4.1 cells

  • Chang, Jai Won;Kim, Soohyun;Lee, Eun Young;Leem, Chae Hun;Kim, Suhn Hee;Park, Chun Sik
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제26권6호
    • /
    • pp.479-499
    • /
    • 2022
  • The lack of a clonal renin-secreting cell line has greatly hindered the investigation of the regulatory mechanisms of renin secretion at the cellular, biochemical, and molecular levels. In the present study, we investigated whether it was possible to induce phenotypic switching of the renin-expressing clonal cell line As4.1 from constitutive inactive renin secretion to regulated active renin secretion. When grown to postconfluence for at least two days in media containing fetal bovine serum or insulin-like growth factor-1, the formation of cell-cell contacts via N-cadherin triggered downstream cellular signaling cascades and activated smooth muscle-specific genes, culminating in phenotypic switching to a regulated active renin secretion phenotype, including responding to the key stimuli of active renin secretion. With the use of phenotype-switched As4.1 cells, we provide the first evidence that active renin secretion via exocytosis is regulated by phosphorylation/dephosphorylation of the 20 kDa myosin light chain. The molecular mechanism of phenotypic switching in As4.1 cells described here could serve as a working model for full phenotypic modulation of other secretory cell lines with incomplete phenotypes.

Anticancer Activity of Acanthopanax trifoliatus (L) Merr Extracts is Associated with Inhibition of NF-κB Activity and Decreased Erk1/2 and Akt Phosphorylation

  • Wang, Hua-Qian;Li, Dong-Li;Lu, Yu-Jing;Cui, Xiao-Xing;Zhou, Xiao-Fen;Lin, Wei-Ping;Conney, Allan H.;Zhang, Kun;Du, Zhi-Yun;Zheng, Xi
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권21호
    • /
    • pp.9341-9346
    • /
    • 2014
  • Acanthopanax trifoliatus (L) Merr (AT) is commonly used as an herbal medicine and edible plant in some areas of China and other Asian countries. AT is thought to have anticancer effects, but potential mechanisms remain unknown. To assess the anticancer properties of AT, we exposed prostate cancer cells to AT extracts and assessed cell proliferation and signaling pathways. An ethanol extract of AT was suspended in water followed by sequential extraction with petroleum ether, ethyl acetate and n-butanol. PC-3 cells were treated with different concentrations of each extract and cell viability was determined by the MTT and trypan blue exclusion assays. The ethyl acetate extract of the ethanol extract had a stronger inhibitory effect on growth and a stronger stimulatory effect on apoptosis than any of the other extracts. Mechanistic studies demonstrated that the ethyl acetate extract suppressed the transcriptional activity of NF-${\kappa}B$, increased the level of caspase-3, and decreased the levels of phospho-Erk1/2 and phospho-Akt. This is the first report on the anticancer activity of AT in cultured human prostate cancer cells. The results suggest that AT can provide a plant-based medicine for the treatment or prevention of prostate cancer.

Aspergillus nidulans의 광 조건하 유성분화에 관여하는 silA 유전자의 분리 및 기능분석 (Isolation and Functional Analysis of the silA Gene That Controls Sexual Development in Response to Light in Aspergillus nidulans)

  • 한상용;고진아;김종학;한규용;한갑훈;한동민
    • 한국균학회지
    • /
    • 제36권2호
    • /
    • pp.189-195
    • /
    • 2008
  • Aspergillus nidulans는 빛이 없는 조건에서는 유성분화가 주로 일어나고 빛이 있는 조건에서는 유성분화가 억제되고 대신 무성분화가 유도된다. 빛에 의해서 유성분화가 억제되는 것은 빛에 반응하여 유성 또는 무성분화를 조절하는 유전자가 있다는 것을 시사한다. 따라서 빛에 의해서 조절되는 유전자를 연구하기 위하여 광 조건하에서 유성분화를 하는 silA98 돌연변이를 분리하였으며, 이를 보완하는 유전자를 분리 및 분석하고자 A. nidulans의 AMA-NotI genomic library로부터 silA98 돌연변이를 상보하는 유전자 silA를 분리하였다. silA 유전자의 예상 ORF는 2,388 bp의 염기로 구성되어지고 795개의 아미노산을 암호화하고 있었다. 이 유전자는 Saccharomyces cerevisiae의 ARO80 유전자와 상동성을 보이며 SilA 단백질의 N 말단에는 약 51.9%의 상동성을 가지는 ${Zn_2}{Cys_6}$ motif를 지니고 있었다. silA 유전자 결손돌연변이주는 광 존재 하에서뿐만 아니라 고농도의 sorbitol에서도 유성분화가 유도되었다. 이는 silA 유전자가 빛과 고삼투 조건에서 유성분화를 억제하는 조절과정에 관여하고 있음을 의미한다. silA 유전자를 niiA promoter로 과다 발현시켰을 때의 형질은 야생형과 큰 차이를 보이지 않았다.

시각 셀 OOK 변조 : MIMO CamCom 연구 사례 (Visual Cell OOK Modulation : A Case Study of MIMO CamCom)

  • 레투안남;장영민
    • 한국통신학회논문지
    • /
    • 제38C권9호
    • /
    • pp.781-786
    • /
    • 2013
  • Multiplexing information over parallel data channels based on RF MIMO concept is possible to achieve considerable data rates over large transmission ranges with just a single transmitting element. Visual multiplexing MIMO techniques will send independent streams of bits using the multiple elements of the light transmitter array and recording over a group of camera pixels can further enhance the data rates. The proposed system is a combination of the reliance on computer vision algorithms for tracking and OOK cell frame modulation. LED array are controlled to transmit message in the form of digital information using ON-OFF signaling with ON-OFF pulses (ON = bit 1, OFF = bit 0). A camera captures image frames of the array which are then individually processed and sequentially decoded to retrieve data. To demodulated data transmission, a motion tracking algorithm is implemented in OpenCV (Open source Computer Vision library) to classify the transmission pattern. One of the most advantages of proposed architecture is Computer Vision (CV) based image analysis techniques which can be used to spatially separate signals and remove interferences from ambient light. It will be the future challenges and opportunities for mobile communication networking research.

빛의 존재하에서도 유성분화를 하는 Aspergillus nidulans의 돌연변이체 분리 및 분석 (Isolation and Characterization of Aspergillus nidulans Mutants Which Undergo Sexual Development in Light Exposure)

  • 민정렬;김혜련;한갑훈;한동민
    • 미생물학회지
    • /
    • 제43권2호
    • /
    • pp.77-82
    • /
    • 2007
  • 자웅동체 자낭균류인 Aspergillus nidulans의 유성분화는 다양한 외부 환경 스트레스, 즉, 아세트산을 함유한 배지, 가시광선의 조사, 높은 삼투압 조건 등에서 강하게 저해 받는다. 본 연구에서는 이에 관련된 유전자들을 분리, 분석하기 위하여 다양한 외부 환경 스트레스를 준 상태에서도 정상적으로 유성포자를 만들 수 있는 돌연변이 균주들을 분리하였다. 총 167개의 돌연변이 균주들 중에서 152종의 균주들은 각각 빛, 삼투, 아세트산 등의 조건에서 유성분화를 할 수 있었으나 두가지 이상을 동시에 주었을 때에는 유성분화를 하지 못하였다. 또한 6개의 돌연변이 균주들은 KCl 첨가 배지에서는 야생형과 변화가 없었으나 빛을 쬐거나 아세트산배지에서는 유성분화를 진행하였다. 그리고, 3개의 돌연변이 균주는 각각의 단일 스트레스 조건뿐만 아니라 KCl과 아세트산이 함께 들어있는 배지에서도 유성분화를 할 수 있었다. 이들 가운데 아세트산과 KCl 배지에서는 야생형과 표현형이 동일하나, 빛이 있는 조건에서는 야생형과 달리 유성분화를 하는 돌연변이 6균주를 얻었으며 이를 SIL 돌연변이라 칭하였다. 상보군 검정결과 이들은 모두 각각 다른 돌연변이를 가지고 있는 것으로 파악되어 silA에서 silF까지 여섯 그룹으로 명명하였고, 우열검정 결과 이들은 모두 열성임이 확인되었다. 대부분의 균주들은 각각 3종류의 스트레스 조건에서 유성분화를 하는 돌연변이들이었기 때문에, 특별하게 빛에만 반응하여 분화에 영향을 주는 유전자는 몇몇에 불과하고, 다른 스트레스들과 관련된 유전자와 연관성이 많으며, 성장에 있어서는 외부 환경 스트레스에 따른 영향은 크지 않은 것으로 사료된다.

Black ginseng extract ameliorates hypercholesterolemia in rats

  • Saba, Evelyn;Jeon, Bo Ra;Jeong, Da-Hye;Lee, Kija;Goo, Youn-Kyoung;Kim, Seung-Hyung;Sung, Chang-Keun;Roh, Seong-Soo;Kim, Sung Dae;Kim, Hyun-Kyoung;Rhee, Man-Hee
    • Journal of Ginseng Research
    • /
    • 제40권2호
    • /
    • pp.160-168
    • /
    • 2016
  • Background: Ginseng (Panax ginseng Meyer) is a well-characterized medicinal herb listed in the classic oriental herbal dictionary as "Shin-nong-bon-cho-kyung." Ginseng has diverse pharmacologic and therapeutic properties. Black ginseng (BG, Ginseng Radix nigra) is produced by repeatedly steaming fresh ginseng nine times. Studies of BG have shown that prolonged heat treatment enhances the antioxidant activity with increased radical scavenging activity. Several recent studies have showed the effects of BG on increased lipid profiles in mice. In this study report the effects of water and ethanol extracts of BG on hypercholesterolemia in rats. To our knowledge, this is the first time such an effect has been reported. Methods: Experiments were conducted on male Sprague Dawley rats fed with a high-cholesterol diet supplemented with the water and ethanol extracts of BG (200 mg/kg). Their blood cholesterol levels, serum white blood cell levels, and cholesterol-metabolizing marker genes messenger RNA (mRNA) expression were determined. Liver and adipose tissues were histologically analyzed. Results: We found that BG extracts efficiently reduced the total serum cholesterol levels, low-density lipoprotein (LDL) levels with increased food efficiency ratio and increased number of neutrophil cells. It also attenuated the key genes responsible for lipogenesis, that is, acetyl-coenzyme A (CoA) acetyltransferase 2, 3-hydroxy-3-methyl-glutaryl-CoA reductase, and sterol regulatory element-binding protein 2, at the mRNA level inside liver cells. Furthermore, the BG extract also reduced the accumulation of fat in adipose tissues, and inhibited the neutral fat content in liver cells stained with hematoxylin and eosin and oil red O. Conclusion: Administration of BG extracts to Sprague Dawley rats fed with high-cholesterol diet ameliorated hypercholesterolemia, which was mediated via modulation of cholesterol-metabolizing marker genes. This data throw a light on BG's cardioprotective effects.

Myristoleic Acid Promotes Anagen Signaling by Autophagy through Activating Wnt/β-Catenin and ERK Pathways in Dermal Papilla Cells

  • Choi, Youn Kyung;Kang, Jung-Il;Hyun, Jin Won;Koh, Young Sang;Kang, Ji-Hoon;Hyun, Chang-Gu;Yoon, Kyung-Sup;Lee, Kwang Sik;Lee, Chun Mong;Kim, Tae Yang;Yoo, Eun-Sook;Kang, Hee-Kyoung
    • Biomolecules & Therapeutics
    • /
    • 제29권2호
    • /
    • pp.211-219
    • /
    • 2021
  • Alopecia is a distressing condition caused by the dysregulation of anagen, catagen, and telogen in the hair cycle. Dermal papilla cells (DPCs) regulate the hair cycle and play important roles in hair growth and regeneration. Myristoleic acid (MA) increases Wnt reporter activity in DPCs. However, the action mechanisms of MA on the stimulation of anagen signaling in DPCs is not known. In this study, we evaluated the effects of MA on anagen-activating signaling pathways in DPCs. MA significantly increased DPC proliferation and stimulated the G2/M phase, accompanied by increasing cyclin A, Cdc2, and cyclin B1. To elucidate the mechanism by which MA promotes DPC proliferation, we evaluated the effect of MA on autophagy and intracellular pathways. MA induced autophagosome formation by decreasing the levels of the phospho-mammalian target of rapamycin (phospho-mTOR) and increasing autophagy-related 7 (Atg7) and microtubule-associated protein 1A/1B-light chain 3II (LC3II). MA also increased the phosphorylation levels of Wnt/β-catenin proteins, such as GSK3β (Ser9) and β-catenin (Ser552 and Ser675). Treatment with XAV939, an inhibitor of the Wnt/β-catenin pathway, attenuated the MA-induced increase in β-catenin nuclear translocation. Moreover, XAV939 reduced MA-induced effects on cell cycle progression, autophagy, and DPC proliferation. On the other hand, MA increased the levels of phospho (Thr202/Tyr204)-extracellular signal regulated kinases (ERK). MA-induced ERK phosphorylation led to changes in the expression levels of Cdc2, Atg7 and LC3II, as well as DPC proliferation. Our results suggest that MA promotes anagen signaling via autophagy and cell cycle progression by activating the Wnt/β-catenin and ERK pathways in DPCs.

A Novel All-trans Retinoid Acid Derivative N-(3-trifluoromethyl-phenyl)-Retinamide Inhibits Lung Adenocarcinoma A549 Cell Migration through Down-regulating Expression of Myosin Light Chain Kinase

  • Fan, Ting-Ting;Cheng, Ying;Wang, Yin-Feng;Gui, Shu-Yu;Chen, Fei-Hu;Zhou, Qing;Wang, Yuan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권18호
    • /
    • pp.7687-7692
    • /
    • 2014
  • Aim: To observe the effects of a novel all-trans retinoid acid (ATRA) derivative, N-(3-trifluoromethyl-phenyl)-retinamide (ATPR), on lung adenocarcinoma A549 cells and to explore the potential mechanism of ATPR inhibiting of A549 cell migration. Materials and Methods: The cytotoxicity of ATRA and ATPR on A549 cells was assessed using MTT assay. Wound healing assays were used to analyze the influences of ATRA, ATPR, ML-7 (a highly selective inhibitor of myosin light chain kinase (MLCK)), PMA (an activator of MAPKs) and PD98059 (a selective inhibitor of ERK1/2) on the migration of A549 cells. Expression of MLCK and phosphorylation of myosin light chain (MLC) were assessed by Western blotting. Results: ATRA and ATPR inhibited the proliferation of A549 cells in a dose- and time-dependent manner, and the effect of ATPR was much more remarkable compared with ATRA. Relative migration rate and migration distance of A549 cells both decreased significantly after treatment with ATPR or ML-7. The effect on cell migration of PD98059 combining ATPR treatment was more notable than that of ATPR alone. Moreover, compared with control groups, the expression levels of MLCK and phosphorylated MLC in A549 cells were both clearly reduced in ATRA and ATPR groups. Conclusions: ATPR could suppress the migration and invasion of A549 cells, and the mechanism might be concerned with down-regulating the expression of MLCK in the ERK-MAPK signaling pathway, pointing to therapeutic prospects in lung cancer.

Update on the Effects of Sound Wave on Plants

  • Chowdhury, Md. Emran Khan;Lim, Hyoun-Sub;Bae, Hanhong
    • 식물병연구
    • /
    • 제20권1호
    • /
    • pp.1-7
    • /
    • 2014
  • Plant growth is considered the sum of cell proliferation and subsequent elongation of the cells. The continuous proliferation and elongation of plant cells are vital to the production of new organs, which have a significant impact on overall plant growth. Accordingly, the relationship between environmental stimuli, such as temperature, light, wind, and sound waves to plant growth is of great interest in studies of plant development. Sound waves can have negative or positive effects on plant growth. In this review paper we have summarized the relationship between sound waves and plant growth response. Sound waves with specific frequencies and intensities can have positive effects on various plant biological indices including seed germination, root elongation, plant height, callus growth, cell cycling, signaling transduction systems, enzymatic and hormonal activities, and gene expression.