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为在转录水平解析杜仲叶片发育过程中的基因表达模式,该研究通过数字基因表达谱技术对‘华仲6号’杜仲叶片从展叶(4月)到落叶(10月)不同发育时期的基因表达水平进行比较分析,共获得差异基因3 002个,其中1 764个表达量上调,1 238个下调,这些差异表达基因主要行使催化、氧化还原等功能,参与代谢过程和生物过程等;进一步Pathway富集分析发现,苯丙素类生物合成途径相关基因被富集,其中调控绿原酸合成的6个基因差异表达显著;对这些基因表达模式进行分析显示,4月中旬和9月中旬基因的表达量较高,暗示这两个时期对于绿原酸的合成具有重要作用。荧光定量RT-PCR检测6个绿原酸合成相关基因和12个随机选择的差异表达基因,验证结果显示表达谱测序结果可靠。该研究结果为揭示杜仲叶片在不同发育时期的分子调控机制奠定了基础,并为深入解析杜仲绿原酸合成机理,进而通过分子育种手段提高杜仲绿原酸含量提供新的路径。  相似文献   
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AGC protein kinases play important roles in plant growth and development.Several AGC kinases in Arabidopsis have been functionally characterized.However,the"AGC Other"subfamily,including IRE,IREH1,IRE3 and IRE4,has not been well understood.Here,we reported that ireh1 mutants displayed a root skewing phenotype,which can be enhanced by ire3 mutation.IREH1 and IRE3 were expressed in roots,consistent with their function in controlling root skewing.The fluorescence intensities of the microtubule marker KNpro:EGFP-MBD were decreased in ireh1,ire3 and ireh1 ire3 mutants compared to wild type.The microtubule arrangements in ireh1 and ireh1 ire3 mutants were also altered.IREH1 physically interacted with IRE3 in vitro and in planta.Thus,our findings demonstrate that IREH1 and IRE3 protein kinases play important roles in controlling root skewing,and maintaining microtubule network in Arabidopsis.  相似文献   
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Toll-like receptor 2 (TLR2) is a bridge between innate immunity and adaptive immunity. TLR2 agonists have been exploited as potential vaccine adjuvants and antitumor agents. However, no TLR2 agonists have been approved by FDA up to now. To discover drug-like TLR2 selective agonists, a novel series of Pam3CSK4 derivatives were designed based on the crystal structure of hTLR2-hTLR1-Pam3CSK4 complex, synthesized and evaluated for their immune-stimulatory activities. Among them, 35c was identified as a murine-specific TLR2 agonist, while 35f was a human-specific TLR2 agonist. Besides, 35d (human and murine TLR2 agonist) showed TLR2 agonistic activity comparable to Pam3CSK4, which included: elevated IL-6 expression level (EC50 = 83.08 ± 5.94 nM), up-regulated TNF-α and IL-6 mRNA expression and promoted maturation of DCs through activating the NF-κB signaling pathway. TLRs antibodies test showed that 35a and 35d were TLR2/1 agonists, while 35f was a TLR2/6 agonist.  相似文献   
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Recently, the incidence of inflammatory bowel diseases, especially the Crohn's disease (CD) and gastrointestinal luminal tuberculosis (ITB), has grown rapidly worldwide. Currently there is no general gold standard to distinguish between CD and ITB tissues, which both have tuberculosis and surrounding fibrous structures. Mueller matrix imaging technique is suitable for describing the location, density and distribution behavior of such fibrous structures. In this study, we apply the Mueller matrix microscopic imaging to the CD and ITB tissue samples. The 2D Mueller matrix images of the CD and ITB tissue slices are measured using the Mueller matrix microscope developed in our previous study, then the Mueller matrix polar decomposition and Mueller matrix transformation parameters are calculated. To evaluate the distribution features of the fibrous structures surrounding the tuberculosis areas more quantitatively and precisely, we analyze the retardance related Mueller matrix derived parameters, which show clear different distribution behaviors between the CD and ITB tissues, using the Tamura image processing method. It is demonstrated that the Mueller matrix derived parameters can reveal the structural features of tuberculosis areas and be used as quantitative indicators to distinguish between CD and ITB tissues, which may be useful for the clinical diagnosis.   相似文献   
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