• 제목/요약/키워드: gene disruption

검색결과 164건 처리시간 0.029초

잎의 발달단계의 leaf index를 조절하는 애기장대 MACROPHYLLA/ROTUNDIFOLIA3 유전자 (MACROPHYLLA/ROTUNDIFOLIA3 gene of Arabidopsis controls leaf index during leaf development)

  • 전상은;투말라 찬드라쉐이커;조규형;이영병;형남인;남재성;김경태
    • Journal of Plant Biotechnology
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    • 제38권4호
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    • pp.285-292
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    • 2011
  • 식물 잎의 발달과정에서 heteroblasty는 외부 환경에 대한 식물의 형태적 적응 방법을 매우 잘 반영하며 이에 따른 변화는 기관의 최종 형태와 크기에 영향을 미친다. Heteroblasty를 나타내는 인자 중에서 leaf index는 단엽식물의 잎의 최종 모양과 크기를 나타내는 대표적인 인자이다. Leaf index는 결국 잎몸에서의 세포 증식과 세포 신장의 두 요인에 의해 결정된다. 비록 세포의 증식과 신장을 조절하는 유전자와 조절 기작들이 연구되고 있으나 큰 청사진을 제시하기에는 아직 미흡하다. 본 연구에서는 발달과정 중 잎의 leaf index 조절에 관여하는 유전자를 밝히고 그 조절 기작을 알아내기 위하여 애기장대 돌연변이체를 이용한 분자유전학적, 생리학적인 실험을 수행하였다. 잎과 잎 세포가 커지는 돌연변이체인 macrophylla (mac)를 선발하여 잎의 확장과정과 leaf index의 이상으로 인해 잎 기관의 모양뿐 만 아니라 heteroblasty에 변화가 발생했다는 사실을 밝혀냈다. 또한 이 돌연변이체는 기존에 알려진 ROTUNDIFOLIA3 (ROT3) 유전자의 점 돌연변이에 의해 일어났다고 판명되었고 mac/rot3-5로 명명되었다. 브라시노스테로이드 처리로 인해 ROT3 유전자의 발현이 음성 되먹임 저해를 받는 것으로 보아 ROT3 유전자가 브라시노스테로이드 생합성에 관여함을 제시하였다. 또한 암상태에서 ROT3 유전자의 발현이 증가하며, mac/rot3-5 돌연변이체가 야생형보다 암반응이 약하게 나타났다. 이러한 분석 결과를 토대로 본 논문은 ROT3 유전자가 잎의 확장과정에서 잎의 leaf index 조절과 고유한 heteroblasty의 정립에 중요한 역할을 수행하며, 브라시노스테로이드 호르몬의 조절을 통하여 음지회피성과 같은 환경조절반응을 수행하고 있다는 새로운 사실을 제시하였다.

Deregulated Expression of Cry1 and Cry2 in Human Gliomas

  • Luo, Yong;Wang, Fan;Chen, Lv-An;Chen, Xiao-Wei;Chen, Zhi-Jun;Liu, Ping-Fei;Li, Fen-Fen;Li, Cai-Yan;Liang, Wu
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권11호
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    • pp.5725-5728
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    • 2012
  • Growing evidence shows that deregulation of the circadian clock plays an important role in the development of malignant tumors, including gliomas. However, the molecular mechanisms of gene chnages controlling circadian rhythm in glioma cells have not been explored. Using real time polymerase chain reaction and immunohistochemistry techniques, we examined the expression of two important clock genes, cry1 and cry2, in 69 gliomas. In this study, out of 69 gliomas, 38 were cry1-positive, and 51 were cry2-positive. The expression levels of cry1 and cry2 in glioma cells were significantly different from the surrounding non-glioma cells (P<0.01). The difference in the expression rate of cry1 and cry 2 in high-grade (grade III and IV) and low-grade (grade 1 and II) gliomas was non-significant (P>0.05) but there was a difference in the intensity of immunoactivity for cry 2 between high-grade gliomas and low-grade gliomas (r=-0.384, P=0.021). In this study, we found that the expression of cry1 and cry2 in glioma cells was much lower than in the surrounding non-glioma cells. Therefore, we suggest that disturbances in cry1 and cry2 expression may result in the disruption of the control of normal circadian rhythm, thus benefiting the survival of glioma cells. Differential expression of circadian clock genes in glioma and non-glioma cells may provide a molecular basis for the chemotherapy of gliomas.

Integration Sites and Genotype Distributions of Human Papillomavirus in Cervical Intraepithelial Neoplasia

  • Wang, Li;Dai, Shu-Zhen;Chu, Hui-Jun;Cui, Hong-Fei;Xu, Xiao-Yan
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권6호
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    • pp.3837-3841
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    • 2013
  • Objectives: To analyse HPV integration prevalence and genotype distributions in cervical intraepithelial neoplasia (CIN) in east part of China, furthermore to assess preferential sites for common HPV integrations and provide baseline information for cervical abnormality screening and prevention. Methods: Integration of HPV in 113 paraffin-embedded cervical intraepithelial neoplasia samples was assessed using Gencap technology in Key Laboratory of Biotechnologies in BGI-Shenzhen. Results: 64 samples were HPV-integrated and as the cervical lesions increased, the integration rate became higher significantly (P=0.002). Fifteen different HPV genotypes were detected, 14 high-risk (16, 18, 31, 33, 51, 52, 56, 58, 66, 68) and 1 low-risk (11). The most common genotypes were HPV-16, 58, 33, 52, 66, and 56. Thirteen patients had co-integration involving mainly HPV-16 and 58. The frequency of HPV gene disruption was higher in L1 and E1 genes than in other regions of the viral genomes. Conclusion: Some 56.6% of CIN lesions in Qingdao had HPV integrations, and 67.2% of HPV-integrated patients were HPV-16 and 58, more prone to be integrated in younger patients below 45 years old. There exist preferential sites for HPV-16 and HPV-58 integration, and they are more likely to be disrupted in the L1 and E1 loci.

Functional Analysis of a Histidine Auxotrophic Mutation in Gibberella zeae

  • Seo, Back-Won;Kim, Hee-Kyoung;Lee, Yin-Won;Yun, Sung-Hwan
    • The Plant Pathology Journal
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    • 제23권2호
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    • pp.51-56
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    • 2007
  • A plant pathogenic fungus, Gibberella zeae (anamorph: Fusarium graminearum), not only generates economic losses by causing disease on cereal grains, but also leads to severe toxicosis in human and animals through the production of mycotoxins in infected plants. Here, we characterized a histidine auxotrophic mutant of G. zeae, designated Z43R1092, which was generated using a restriction enzyme-mediated integration (REMI) procedure. The mutant exhibited pleiotropic phenotypic changes, including a reduction in mycelial growth and virulence and loss of sexual reproduction. Outcrossing analysis confirmed that the histidine auxotrophy is linked to the insertional vector in Z43R1092. Molecular analysis showed that the histidine requirement of Z43R1092 is caused by a disruption of an open reading frame, designated GzHIS7. The deduced product of GzHIS7 encodes a putative enzyme with an N-terminal glutamine amidotransferase and a C-terminal cyclase domain, similar to the Saccharomyces cerevisiae HIS7 required for histidine biosynthesis. The subsequent gene deletion and complementation analyses confirmed the functions of GzHIS7 in G. zeae. This is the first report of the molecular characterization of histidine auxotrophy in G. zeae, and our results demonstrate that correct histidine biosynthesis is essential for virulence, as well as sexual development, in G. zeae. In addition, our results could provide a G. zeae histidine auxotroph as a recipient strain for genetic transformation using this new selectable marker.

Efficiency and Midgut Histopathological Effect of the Newly Isolated Bacillus thuringiensis KS ${\delta}$-Endotoxins on the Emergent Pest Tuta absoluta

  • Jamoussi, Kais;Sellami, Sameh;Nasfi, Zina;Krichen-Makni, Saloua;Tounsi, Slim
    • Journal of Microbiology and Biotechnology
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    • 제23권8호
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    • pp.1099-1106
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    • 2013
  • Tuta absoluta (Povolny, 1994) is a devastating moth to the Solanaceae plants. It is a challenging pest to control, especially on tomatoes. In this work, we studied the entomopathogenic activity of the Cry-forming ${\delta}$-endotoxins produced by Bacillus thuringiensis strain KS and B. thuringiensis kurstaki reference strain HD1 against T. absoluta. These strains carried the cry2, cry1Ab, cry1Aa/cry1Ac, and cry1I genes, and KS also carried a cry1C gene. The ${\delta}$-endotoxins of KS were approximately twofold more toxic against the third instar larvae than those of HD1, as they showed lower 50% and 90% lethal concentrations (0.80 and 2.70 ${\mu}g/cm^2$ (${\delta}$-endotoxins/tomato leaf)) compared with those of HD1 (1.70 and 4.50 ${\mu}g/cm^2$) (p < 0.05). Additionally, the larvae protease extract showed at least six caseinolytic activities, which activated the KS and HD1 ${\delta}$-endotoxins, yielding the active toxins of about 65 kDa and the protease-resistant core of about 58 kDa. Moreover, the histopathological effects of KS and HD1 ${\delta}$-endotoxins on the larvae midgut consisted of an apical columnar cell vacuolization, microvillus damage, and epithelial cell disruption. These results showed that the KS strain could be a candidate for T. absoluta control.

A WblA-Binding Protein, SpiA, Involved in Streptomyces Oxidative Stress Response

  • Kim, Jin-Su;Lee, Han-Na;Lee, Heung-Shick;Kim, Pil;Kim, Eung-Soo
    • Journal of Microbiology and Biotechnology
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    • 제23권10호
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    • pp.1365-1371
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    • 2013
  • The Streptomyces coelicolor wblA gene is known to play a negative role in both antibiotic biosynthesis and the expression of genes responding to oxidative stress. Recently, WhcA, a WblA ortholog protein, was confirmed to interact with dioxygenase-encoding SpiA ($\underline{s}$tress $\underline{p}$rotein $\underline{i}$nteracting with Whc$\underline{A}$) in Corynebacterium glutamicum. We describe here the identification of a SpiA ortholog SCO2553 protein ($SpiA_{sc}$) that interacts with WblA in S. coelicolor. Using heterologous expression in E. coli and in vitro pull-down assays, we show that WblA specifically binds $SpiA_{sc}$, and is influenced by oxidants such as diamide. These data indicate that the interaction between WblA and $SpiA_{sc}$ is not only specific but also modulated by the redox status of the cell. Moreover, a $spiA_{sc}$-disruption mutant exhibited a less sensitive response to the oxidative stress induced by diamide present in solid plate culture. Real-time RT-PCR analysis also showed that transcription levels of oxidative stress response genes (sodF, sodF2, and trxB) were higher in the $spiA_{sc}$-deletion mutant than in wild-type S. coelicolor. These results show that $SpiA_{sc}$ negatively regulates WblA during oxidative stress responses in S. coelicolor.

내분비계 장애물질이 어류의 HPG, HPT, HPA 축에 미치는 연계영향 (A Review on the Effects of Endocrine Disruptors on the Interaction between HPG, HPT, and HPA Axes in Fish)

  • 장솔;지경희
    • 한국환경보건학회지
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    • 제41권3호
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    • pp.147-162
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    • 2015
  • Objectives: The objective of this review was to summarize the primary role of three representative endocrine axes in aquatic vertebrates and discuss the effects on endocrine systems and their interactions in teleost fish after exposure to environmental contaminants. Methods: We summarized individual traits and mechanisms for hormonal and transcriptional interactions between the hypothalamic-pituitary-gonad (HPG), hypothalamic-pituitary-thyroid (HPT), and hypothalamic-pituitary-adrenal (HPA) axes in fish. We also provided a brief discussion on the effects of nonylphenol-induced toxicity on endocrine systems and their interactions in fish as a demonstration of holistic explanation. Results: Currently-available data showed that thyroid dysfunction is associated with reproductive toxicity due to changes in steroidogenic gene expressions and sex hormone levels as well as gonad glands in fish. As an example, we demonstrated that exposure to nonylphenol could induce estrogenicity in male fish by decreasing thyroid hormones, which contributes to increased aromatase expression. Although the mechanisms are complicated and involved in multiple ways, a number of studies have shown that sex steroids influence the HPT axis or the HPA axis in fish, indicating bi-directional crosstalk. Critically missing is information on the primary target or toxicity mechanisms of environmental contaminants among the three endocrine axes, so further studies are needed to explore those possibilities. Conclusions: This review highlights the interactions between the HPG, HPT, and HPA axes in fish in order to better understand how these endocrine systems could interact with each other in situations of exposure to endocrine disrupting chemicals.

E1/E2 of Hepatitis C Virus Genotype-4 and Apoptosis

  • Zekri, Abdel-Rahman N;Sobhy, Esraa;Hussein, Nehal;Ahmed, Ola S;Hussein, Amira;Shoman, Sahar;Soliman, Amira H;El-Din, Hanaa M Alam
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권7호
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    • pp.3131-3138
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    • 2016
  • Several studies have addressed the possible role of hepatitis C virus genotype-4 (HCV GT4) in apoptosis. However, this still not fully understood. In the current study a re-constructed clone of E1/E2 polyprotein region of the HCV GT4 was transfected into the Huh7 cell line and a human apoptotic PCR array of 84 genes was used to investigate its possible significance for apoptosis. Out of the 84 genes, only 35 showed significant differential expression, 12 genes being up-regulated and 23 down-regulated. The highest-up regulated genes were APAF1 (apoptotic peptidase-activating factor 1), BID (BH3 interacting domain death agonist) and BCL 10 (B-cell CLL/lymphoma protein 10) with fold regulation of 33.2, 30.1 and 18.9, respectively. The most down-regulated were FAS (TNF receptor super family), TNFRSF10B (tumor necrosis factor receptor super-family member 10b) and FADD (FAS-associated death domain) with fold regulation of -30.2, -27.7 and -14.9, respectively. These results suggest that the E1/E2 proteins may be involved in HCV-induced pathogenesis by modulating apoptosis through the induction of the intrinsic apoptosis pathway and disruption of the BCL2 gene family.

Apoptosis and remodeling in adriamycin-induced cardiomyopathy rat model

  • Hong, Young Mi;Lee, Hyeryon;Cho, Min-Sun;Kim, Kwan Chang
    • Clinical and Experimental Pediatrics
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    • 제60권11호
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    • pp.365-372
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    • 2017
  • Purpose: The mechanism for the pathogenesis of adriamycin (ADR)-induced cardiomyopathy is not yet known. Different hypotheses include the production of free radicals, an interaction between ADR and nuclear components, and a disruption in cardiac-specific gene expression. Apoptosis has also been proposed as being involved in cardiac dysfunction. The purpose of this study was to determine if apoptosis might play a role in ADR-induced cardiomyopathy. Methods: Male Sprague-Dawley rats were separated into 2 groups: the control group (C group) and the experimental group (ADR 5 mg/wk for 3 weeks through intraperitoneal injections; A group). Echocardiographic images were obtained at week 3. Changes in caspase-3, B-cell leukemia/lymphoma (Bcl)-2, Bcl-2-associated X (Bax), interleukin (IL)-6, tumor necrosis $factor-{\alpha}$, brain natriuretic peptide (BNP), troponin I, collagen 1, and collagen 3 protein expression from the left ventricle tissues of C and A group rats were determined by Western blot. Results: Ascites and heart failure as well as left ventricular hypertrophy were noted in the A group. Ejection fraction and shortening fraction were significantly lower in the A group by echocardiography. The expression of caspase-3, Bax, IL-6, BNP, collagen 1, and collagen 3 were significantly higher in the A group as compared with the C group. Protein expression of Bcl-2 decreased significantly in the A group compared with the C group. Conclusion: ADR induced an upregulation of caspase-3, Bax, IL-6, and collagen, as well as a depression in Bcl-2. Thus, apoptosis and fibrosis may play an important role in ADR-induced cardiomyopathy.

Macromolecular Docking Simulation to Identify Binding Site of FGB1 for Antifungal Compounds

  • Soundararajan, Prabhakaran;Sakkiah, Sugunadevi;Sivanesan, Iyyakkannu;Lee, Keun-Woo;Jeong, Byoung-Ryong
    • Bulletin of the Korean Chemical Society
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    • 제32권10호
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    • pp.3675-3681
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    • 2011
  • Fusarium oxysporum, an important pathogen that mainly causes vascular or fusarium wilt disease which leads to economic loss. Disruption of gene encoding a heterotrimeric G-protein-${\beta}$-subunit (FGB1), led to decreased intracellular cAMP levels, reduced pathogenicity, colony morphology, and germination. The plant defense protein, Nicotiana alata defensin (NaD1) displays potent antifungal activity against a variety of agronomically important filamentous fungi. In this paper, we performed a molecular modeling and docking studies to find vital amino acids which can interact with various antifungal compounds using Discovery Studio v2.5 and GRAMMX, respectively. The docking results from FGB1-NaD1 and FGB1-antifungal complexes, revealed the vital amino acids such as His64, Trp65, Ser194, Leu195, Gln237, Phe238, Val324 and Asn326, and suggested that the anidulafungin is a the good antifungal compound.The predicted interaction can greatly assist in understanding structural insights for studying the pathogen and host-component interactions.