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YanPing Wang EJiao Wu Yahuza Lurwanu JiPeng Ding DunChun He Abdul Waheed Oswald Nkurikiyimfura ShiTing Liu WenYang Li ZongHua Wang Lina Yang Jiasui Zhan 《Ecology and evolution》2021,11(10):5484
Genetic variation plays a fundamental role in pathogen''s adaptation to environmental stresses. Pathogens with low genetic variation tend to survive and proliferate more poorly due to their lack of genotypic/phenotypic polymorphisms in responding to fluctuating environments. Evolutionary theory hypothesizes that the adaptive disadvantage of genes with low genomic variation can be compensated for structural diversity of proteins through post‐translation modification (PTM) but this theory is rarely tested experimentally and its implication to sustainable disease management is hardly discussed. In this study, we analyzed nucleotide characteristics of eukaryotic translation elongation factor‐1α (eEF‐lα) gene from 165 Phytophthora infestans isolates and the physical and chemical properties of its derived proteins. We found a low sequence variation of eEF‐lα protein, possibly attributable to purifying selection and a lack of intra‐genic recombination rather than reduced mutation. In the only two isoforms detected by the study, the major one accounted for >95% of the pathogen collection and displayed a significantly higher fitness than the minor one. High lysine representation enhances the opportunity of the eEF‐1α protein to be methylated and the absence of disulfide bonds is consistent with the structural prediction showing that many disordered regions are existed in the protein. Methylation, structural disordering, and possibly other PTMs ensure the ability of the protein to modify its functions during biological, cellular and biochemical processes, and compensate for its adaptive disadvantage caused by sequence conservation. Our results indicate that PTMs may function synergistically with nucleotide codes to regulate the adaptive landscape of eEF‐1α, possibly as well as other housekeeping genes, in P. infestans. Compensatory evolution between pre‐ and post‐translational phase in eEF‐1α could enable pathogens quickly adapting to disease management strategies while efficiently maintaining critical roles of the protein playing in biological, cellular, and biochemical activities. Implications of these results to sustainable plant disease management are discussed. 相似文献
63.
Baowei Jiao Naoko Taniguchi-Ishigaki Cenap Güng?r Marvin A. Peters Ya-Wen Chen Sabine Riethdorf Alexander Drung Leanne G. Ahronian JongDae Shin Rachna Pagnis Klaus Pantel Taro Tachibana Brian C. Lewis Steven A. Johnsen Ingolf Bach 《Molecular biology of the cell》2013,24(19):3085-3096
The X-linked gene Rnf12 encodes the ubiquitin ligase really interesting new gene (RING) finger LIM domain–interacting protein (RLIM)/RING finger protein 12 (Rnf12), which serves as a major sex-specific epigenetic regulator of female mouse nurturing tissues. Early during embryogenesis, RLIM/Rnf12 expressed from the maternal allele is crucial for the development of extraembryonic trophoblast cells. In contrast, in mammary glands of pregnant and lactating adult females RLIM/Rnf12 expressed from the paternal allele functions as a critical survival factor for milk-producing alveolar cells. Although RLIM/Rnf12 is detected mostly in the nucleus, little is known about how and in which cellular compartment(s) RLIM/Rnf12 mediates its biological functions. Here we demonstrate that RLIM/Rnf12 protein shuttles between nucleus and cytoplasm and this is regulated by phosphorylation of serine S214 located within its nuclear localization sequence. We show that shuttling is important for RLIM to exert its biological functions, as alveolar cell survival activity is inhibited in cells expressing shuttling-deficient nuclear or cytoplasmic RLIM/Rnf12. Thus regulated nucleocytoplasmic shuttling of RLIM/Rnf12 coordinates cellular compartments during mammary alveolar cell survival. 相似文献
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Xiao-Wen Zhang Ying-Ying Liu Yi Mu Qian Ren Xiao-Fan Zhao Jin-Xing Wang 《Fish & shellfish immunology》2013,34(5):1112-1118
C-type lectins play important roles in the innate immune system of crustaceans. In this study, a novel C-type lectin gene, designated as PcLec4, was obtained from the red swamp crayfish (Procambarus clarkii). Quantitative real-time polymerase chain reaction revealed that PcLec4 is mainly expressed in the crayfish hepatopancreas and intestine, and the PcLec4 mRNA expression is upregulated after challenged with the bacteria Vibrio anguillarum. PcLec4 was recombinantly expressed in Escherichia coli and anti-PcLec4 polyclonal antiserum was prepared. Binding experiments revealed that the recombinant PcLec4 binds to various bacteria and polysaccharides on the bacterial surface, which suggests that PcLec4 recognizes bacterial pathogens. Overexpression of PcLec4 in crayfish using the pIeLec4 vector was performed. The results show that the crayfish overexpressing PcLec4 eliminate injected V. anguillarum more quickly than the control, which suggests that PcLec4 elicits further immune response for removing invading bacteria. The results of the survival experiment confirmed the function of PcLec4 in resisting V. anguillarum because PcLec4 overexpression in crayfish significantly increased the crayfish survival rate. These results reveal that PcLec4 has an important role in the antibacterial immunity of crayfish, and in vivo PcLec4 overexpression might be used as a disease control strategy in aquiculture. 相似文献
65.
Yuexin Ma Zhiming Liu Zhiping Yang Ming Li Jiao Liu Jian Song 《Fish & shellfish immunology》2013,34(1):66-73
A feeding experiment was conducted to determine effects of Hanseniaspora opuntiae C21 on immune response and disease resistance against Vibrio splendidus infection in juvenile sea cucumbers Apostichopus japonicus. Sea cucumbers were fed with either diets containing C21 at 104, 105 and 106 CFU g?1 feed or a control diet for 30–50 days, respectively. After feeding for 30 days and 45 days, five sea cucumbers from each tank were sampled for immunological analyses. Results indicated that C21 significantly improved the phagocytic activity in coelomocytes of sea cucumbers (P < 0.05). Moreover, C21 administration significantly enhanced lysozyme (LSZ), phenoloxidase activity (PO), total nitric oxide synthase (T-NOS), superoxide dismutase (SOD), alkaline phosphatase (AKP) and acid phosphatase (ACP) activities in coelomic fluid, and LSZ, T-NOS, AKP and ACP activities in coelomocytes lysate supernatant (CLS) of sea cucumbers (P < 0.05). After feeding for 45 days, 10 sea cucumbers from each dose group were challenged with V. splendidus NB13. Cumulative incidence and mortality of sea cucumbers fed with C21 were found to be lower than those of control group. After feeding for 50 days, sea cucumbers in 104 CFU g?1 C21 treatment and control tanks were subjected to acute salinity changes (from 30 to 20) for 24 h in the laboratory, and the immunological parameters were measured to evaluate the immune capacities of the A. japonicus. Phagocytic, LAZ and T-NOS activities of C21-treated group were higher than those of control group, indicating that salinity stress tolerance of sea cucumber was enhanced by C21. The present results showed that a diet supplemented with C21 could stimulate the immune system of juvenile A. japonicus thus enhancing their resistance against V. splendidus. 相似文献
66.
Xiaoyu Liu Ruohua Chen Yanjun Shang Binghua Jiao 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):663-668
In this study we investigated the superoxide radicals scavenging effect and xanthine oxidase inhibitory activity by magnesium lithospermate B, which was originally isolated from the roots of Salvia miltiorrhiza (also named Danshen or Dansham), an important herb in Oriental medicine. Superoxide radicals were generated both in β-NADH/PMS system and xanthine/ xanthine oxidase system. Magnesium lithospermate B significantly inhibited the reduction of NBT induced by superoxide radicals with an IC50 of 29.8 μg/mL and 4.06 μg/mL respectively in the two systems. Further study suggested that magnesium lithospermate B can directly inhibit xanthine oxidase and exhibits competitive inhibition. Magnesium lithospermate B was also found to have the hypouricemic activity in vivo against potassium oxonate-induced hyperuricaemia in mice. After oral administration of magnesium lithospermate B at doses of 10, 20 and 30 mg/kg, there was a significant decrease in the serum urate level when compared to the hyperuricemia control. In addition, magnesium lithospermate B significantly protected HL-60 cells from superoxide radicals-induced apoptosis in the xanthine/ xanthine oxidase reactions. This study provided evidence that magnesium lithospermate B exhibits direct superoxide radicals scavenging and xanthine oxidase inhibitory activity. 相似文献
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Objectives
To assess the feasibility of low-dose prospective ECG-gated dual-source CT (DSCT) in detecting airway anomalies in pediatric patients with cardiovascular anomalies compared with flexible tracheobronchoscopy (FTB).Methods
33 pediatrics with respiratory symptoms who had been revealed cardiovascular anomalies by transthoracic echocardiography underwent FTB and contrast material–enhanced prospective ECG-triggering CT were enrolled. The study was approved by our institution review board and written informed consent was obtained from all patients’ guardian. DSCT examinations were performed to detect cardiovascular abnormalities using weight-adjusted low–dose protocol. Two radiologists independently performed CT image analysis. The FTB reports were reviewed by an experienced pulmonologist. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of DSCT in the detection of airway anomalies were assessed. The tracheobronchial stenoses revealed on FTB were graded. Effective radiation dose was calculated.Results
Thirty cases were diagnosed with tracheobronchial narrowing and/or abnormality in 33 patients by FTB, while 3 patients had normal FTB findings. Twenty-eight cases were diagnosed with airway anomalies by CT, of which 27 were correct positive. 3 patients with normal findings at CT had findings of tracheobronchial narrowing due to tracheobronchomalacia at inspiration at FTB. Sensitivity and specificity of CT were 90.0% (95% CI: 72.3%, 97.4%) and 66.7% (95% CI: 12.5 %, 98.2 %), respectively. PPV and NPV were 96.4% (95% CI: 79.8 %, 99.8%) and 40.0% (95% CI: 7.3%, 83.0%), respectively. Overall accuracy of DSCT in detecting airway anomalies in pediatrics with cardiovascular anomalies was 87.9% (95% CI: 74.5%, 97.6%). In grading of tracheobronchial stenosis, images from CT correlated closely (r = 0.89) with those of FTB. Mean effective dose was 0.60±0.20 mSv.Conclusion
In pediatric patients, ECG-triggered CT to evaluate congenital cardiovascular anomalies can also be used to diagnose and characterize fixed airway involvement in relation to the vascular structures. 相似文献70.
Changjun Wang Lei Shang Yuhai Zhang Jiao Tian Baoxi Wang Xianjun Yang Lijun Sun Chunyan Du Xun Jiang Yongyong Xu 《PloS one》2013,8(10)