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43.
Osmotin or osmotin-like protein, a PR-5 family member, is differentially induced in plants by abiotic and biotic stresses. Here, we demonstrate that the pepper (Capsicum annuum) osmotin-like protein 1 gene, CaOSM1, was required for the defense and hypersensitive cell death response and oxidative burst signaling during Xanthomonas campestris pv. vesicatoria (Xcv) infection. CaOSM1 protein was localized to the plasma membrane in leaf cells of Nicotiana benthamiana. Agrobacterium-mediated transient expression of CaOSM1 in pepper distinctly induced the hypersensitive cell death response and H2O2 accumulation. Knock-down of CaOSM1 in pepper by virus-induced gene silencing increased the susceptibility to Xcv infection, which was accompanied by attenuation of the cell death response and decreased accumulation of H2O2. CaOSM1 overexpression in transgenic Arabidopsis conferred reduced susceptibility and accelerated cell death response and H2O2 accumulation to infection by Pseudomonas syringe pv. tomato and Hyaloperonospora arabidopsidis. Together, these results suggest that CaOSM1 is involved in cell death and oxidative burst responses during plant defense against microbial pathogens. 相似文献
44.
Guo-Zhong Tao Nadja Lehwald Kyu Yun Jang Joy Baek Baohui Xu M. Bishr Omary Karl G. Sylvester 《The Journal of biological chemistry》2013,288(24):17214-17224
Numerous liver diseases are associated with extensive oxidative tissue damage. It is well established that Wnt/β-catenin signaling directs multiple hepatocellular processes, including development, proliferation, regeneration, nutrient homeostasis, and carcinogenesis. It remains unexplored whether Wnt/β-catenin signaling provides hepatocyte protection against hepatotoxin-induced apoptosis. Conditional, liver-specific β-catenin knockdown (KD) mice and their wild-type littermates were challenged by feeding with a hepatotoxin 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) diet to induce chronic oxidative liver injury. Following the DDC diet, mice with β-catenin-deficient hepatocytes demonstrate increased liver injury, indicating an important role of β-catenin signaling for liver protection against oxidative stress. This finding was further confirmed in AML12 hepatocytes with β-catenin signaling manipulation in vitro using paraquat, a known oxidative stress inducer. Immunofluorescence staining revealed an intense nuclear FoxO3 staining in β-catenin-deficient livers, suggesting active FoxO3 signaling in response to DDC-induced liver injury when compared with wild-type controls. Consistently, FoxO3 target genes p27 and Bim were significantly induced in β-catenin KD livers. Conversely, SGK1, a β-catenin target gene, was significantly impaired in β-catenin KD hepatocytes that failed to inactivate FoxO3. Furthermore, shRNA-mediated deletion of FoxO3 increased hepatocyte resistance to oxidative stress-induced apoptosis, confirming a proapoptotic role of FoxO3 in the stressed liver. Our findings suggest that Wnt/β-catenin signaling is required for hepatocyte protection against oxidative stress-induced apoptosis. The inhibition of FoxO through its phosphorylation by β-catenin-induced SGK1 expression reduces the apoptotic function of FoxO3, resulting in increased hepatocyte survival. These findings have relevance for future therapies directed at hepatocyte protection, regeneration, and anti-cancer treatment. 相似文献
45.
Non hemolytic short peptidomimetics as a new class of potent and broad-spectrum antimicrobial agents
Ravichandran N. Murugan Binu Jacob Eun-Hee Kim Mija Ahn Hoik Sohn Ji-Hyung Seo Chaejoon Cheong Jae-Kyung Hyun Kyung S. Lee Song Yub Shin Jeong Kyu Bang 《Bioorganic & medicinal chemistry letters》2013,23(16):4633-4636
Since the bacterial resistance to antibiotics is increasing rapidly, numerous studies have contributed to the design and synthesis of potent synthetic mimics of antimicrobial peptides (AMPs). In an attempt to find the pharmacophore of short antimicrobial peptidomimetics through systematic tuning of hydrophobic and hydrophilic patterns, we have identified a set of short histidine-derived antimicrobial peptides (SAMPs) with potent and broad-spectrum activity. A combination of high antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA), without hemolytic activity and proteolytic stability makes these molecules promising candidates for novel antimicrobial therapeutics. 相似文献
46.
The aim of the current investigation was to test the general convention that the Dasyaceae, Delesseriaceae and Rhodomelaceae are all monophyletic families of the red algal order Ceramiales. Phylogenetic relationships among 45 ceramialean taxa were determined, including eight ceramiacean, 18 dasyacean, nine delesseriacean and eight rhodomelacean species, plus two of uncertain ceramialean affinities, based on 34 anatomical characters and nuclear small subunit (SSU) rDNA sequences. Results from our ‘total-evidence’ approach were consistent with the notion that the Dasyaceae, Delesseriaceae and Rhodomelaceae have evolved from a common ancestor within a paraphyletic Ceramiaceae. Our data indicate, however, that the Rhodomelaceae alone is monophyletic at the family level, with both the Dasyaceae and Delesseriaceae polyphyletic. In particular we resolved two independent and well-supported lineages for the included Dasyaceae, viz., a Dasya group and a Heterosiphonia group, which were as distinct from one another as they were from the Rhodomelaceae and the various lineages of Delesseriaceae. The molecular data alone were equivocal on the issue of monophyly of the Dasyaceae. We therefore advocate conservative taxonomic revisions as an interim step towards eventual resolution of familial-level taxonomy in the Ceramiales. Based on our results, the Heterosiphonioideae H.-G. Choi, Kraft, I.K. Lee et G.W. Saunders subfam. nov. is proposed for Heterosiphonia and five closely related genera, and the Dasyoideae Schmitz et Falkenberg is emended for the remaining taxa. Although the Dasyoideae is a natural group, it is in need of a thorough systematic reinvestigation at the generic level. Our analyses indicate that the genus Dasya is polyphyletic or paraphyletic in excluding Dasysiphonia, Eupogodon and Rhodoptilum and that Heterosiphonia japonica also has affinities to this group, taxonomic issues that will be addressed in detail elsewhere. 相似文献
47.
Hye Ri Park Jiyoon Kim Taekeun Kim Seonmi Jo Miyoung Yeom Bongjin Moon Il Han Choo Jaeick Lee Eun Jeong Lim Ki Duk Park Sun-Joon Min Ghilsoo Nam Gyochang Keum C. Justin Lee Hyunah Choo 《Bioorganic & medicinal chemistry》2013,21(17):5480-5487
In Parkinson’s disease, the motor impairments are mainly caused by the death of dopaminergic neurons. Among the enzymes which are involved in the biosynthesis and catabolism of dopamine, monoamine oxidase B (MAO-B) has been a therapeutic target of Parkinson’s disease. However, due to the undesirable adverse effects, development of alternative MAO-B inhibitors with greater optimal therapeutic potential towards Parkinson’s disease is urgently required. In this study, we designed and synthesized the oxazolopyridine and thiazolopyridine derivatives, and biologically evaluated their inhibitory activities against MAO-B. Structure–activity relationship study revealed that the piperidino group was the best choice for the R1 amino substituent to the oxazolopyridine core structure and the activities of the oxazolopyridines with various phenyl rings were between 267.1 and 889.5 nM in IC50 values. Interestingly, by replacement of the core structure from oxazolopyrine to thiazolopyridine, the activities were significantly improved and the compound 1n with the thiazolopyridine core structure showed the most potent activity with the IC50 value of 26.5 nM. Molecular docking study showed that van der Waals interaction in the human MAO-B active site could explain the enhanced inhibitory activities of thiazolopyridine derivatives. 相似文献
48.
Jeong Kyu Kim 《Entomological Research》2013,43(1):1-11
A total of 107 forms of 88 eumenine wasp species occurring in the Far East were used to produce a more comprehensive picture of the geographical pattern of wasps in the Far East. All forms occurring in the Far East were biogeographically classified into 22 types in four larger categories, and a summarized table and discussion are presented. The eumenine wasp fauna of the Far East was characterized as a mixture of a fair number of endemic elements, a moderate number of transpalearctic elements, and some Oriental elements. The endemism of the Far East reached 0.71 at the species/subspecies level when the calculation was based on true Palearctic elements occurring in Far Eastern Russia, the Korean peninsula and Japan proper. The relationship between the Far Eastern fauna and the Central/Western Palearctic faunas was also analyzed and discussed. The species occurring in each treated district was counted, and provides evidence for the importance of the Korean fauna in biodiversity evaluation/estimation of Far Eastern fauna. The similarity index between the Korean Peninsula and Japan proper, the Korean Peninsula and the Russian Far East, and the Russian Far East and Japan proper was calculated to explain possible factors for faunal formation in the Far East. The distributional pattern of each form treated in this study and its relatives is tabulated in Appendix I. 相似文献
49.
Yoon Seok Choi Jung Eun Lee Seung Joo Nam Jung Tak Park Hyon-Suk Kim Kyu Hun Choi Beom Seok Kim Eui-Cheol Shin 《PloS one》2013,8(4)
In hepatitis C Virus (HCV) high-risk groups, HCV-specific T cell responses have been detected in seronegative, aviremic persons who have no evidence of HCV infection. Herein, we investigated functional profiles of HCV-specific T-cell responses in seronegative, aviremic patients of a HCV high-risk group. Seventy seven hemodialysis patients with chronic renal disease were analyzed by IFN-γ ELISpot assays, and eight of 71 (11.3%) seronegative, aviremic patients displayed HCV-specific T-cell responses. Their HCV-specific memory T cells were characterized by assessing cytokine polyfunctionality, known to provide antiviral protection. By intracellular staining of IFN-γ, TNF-α, IL-2 and MIP-1β, we identified two distinct populations in the seronegative, aviremic patients: polyfunctional responders and TNF-α-predominant responders. In further analysis, occult HCV infection was excluded as a cause of the HCV-specific T cell response via secondary nested RT-PCR of HCV RNA in peripheral blood mononuclear cell samples. HCV-specific T cells targeted multiple epitopes including non-structural proteins in a single patient, implying that their T cells might have been primed by HCV proteins synthesized within the host. We conclude that HCV-specific memory T cells of seronegative, aviremic patients arise from authentic HCV replication in the host, but not from current occult HCV infection. By functional pattern of HCV-specific T cells, there are two distinct populations in these patients: polyfunctional responders and TNF-α-predominant responders. 相似文献
50.
Sang Ouk Chin Sang Youl Rhee Suk Chon You-Cheol Hwang In-Kyung Jeong Seungjoon Oh Kyu Jeung Ahn Ho Yeon Chung Jeong-taek Woo Sung-Woon Kim Jin-Woo Kim Young Seol Kim Hong-Yup Ahn 《PloS one》2013,8(3)