【背景和目的】从蛋白质水平上揭示烟叶衰老机理。【方法】以烤烟品种K326为材料,测定烟叶未熟(IM)、适熟(WM)和过熟(OM)3个时期超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)和抗坏血酸过氧化物酶(APX)活性;采用同位素相对...【背景和目的】从蛋白质水平上揭示烟叶衰老机理。【方法】以烤烟品种K326为材料,测定烟叶未熟(IM)、适熟(WM)和过熟(OM)3个时期超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)和抗坏血酸过氧化物酶(APX)活性;采用同位素相对标记与绝对定量技术(iTRAQ)鉴定3个时期烟叶响应衰老差异表达蛋白,对所获得的差异蛋白进行生物信息学分析,筛选出烟叶衰老潜在靶标蛋白。同时,选择12个蛋白进行平行反应监测(PRM)验证。【结果】(1)随着烟叶成熟度的增加,SOD、CAT、POD和APX活性逐渐降低。(2) 共鉴定出4747种蛋白,过熟与未熟相比,存在321个差异蛋白,包括122个上调蛋白与199个下调蛋白。过熟与适熟相比,存在319个差异蛋白,其中124个表现为上调,195个表现为下调。适熟与未熟相比,发现223个差异蛋白质,包括125个上调蛋白和98个下调蛋白。(3)在基因本体(Gene Ontology,GO)功能注释中,差异蛋白质主要参与生物过程(代谢过程、细胞过程)、细胞组成(细胞、细胞组分、细胞器)和分子功能(催化活性)。(4)在京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)功能富集中,差异蛋白质显著富集于代谢途径、光合作用、次生代谢产物的生物合成等。(5)PRM验证发现对比组OM vs IM,OM vs WM和WM vs IM中,分别有10/9/10个蛋白质验证结果与iTRAQ定量表现出相同的趋势。6个差异蛋白包括Q1WL43、A0A1S4DCM1、A0A1S4C433、A0A1S4AKK6、A0A1S3ZQP6、A0A140G1P2可能是烟叶衰老潜在靶标蛋白。【结论】本研究采用iTRAQ 结合PRM 技术,筛选出烟草叶片响应衰老差异表达蛋白,可为深入认识烟草衰老的应答分子调控机制奠定基础。展开更多
In this paper,using cyclostationarity-based sensing method to detect the presence of Orthogonal Frequency Division Multiplexing(OFDM) signal over doubly-selective fading channels is studied.By approximating the channe...In this paper,using cyclostationarity-based sensing method to detect the presence of Orthogonal Frequency Division Multiplexing(OFDM) signal over doubly-selective fading channels is studied.By approximating the channel with Basis Expansion Model(BEM),we derive the second-order cyclostationary statistics of the received OFDM signal over doubly-selective fading channels.Theoretical analysis indicates that new cyclostationary signatures produced by Doppler spread and multipath delay can be further exploited in the detecting process.Simulation examples demonstrate that the sensing methods using channel-induced cyclostationary features provide substantial improvements on detection performance.展开更多
文摘【背景和目的】从蛋白质水平上揭示烟叶衰老机理。【方法】以烤烟品种K326为材料,测定烟叶未熟(IM)、适熟(WM)和过熟(OM)3个时期超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)和抗坏血酸过氧化物酶(APX)活性;采用同位素相对标记与绝对定量技术(iTRAQ)鉴定3个时期烟叶响应衰老差异表达蛋白,对所获得的差异蛋白进行生物信息学分析,筛选出烟叶衰老潜在靶标蛋白。同时,选择12个蛋白进行平行反应监测(PRM)验证。【结果】(1)随着烟叶成熟度的增加,SOD、CAT、POD和APX活性逐渐降低。(2) 共鉴定出4747种蛋白,过熟与未熟相比,存在321个差异蛋白,包括122个上调蛋白与199个下调蛋白。过熟与适熟相比,存在319个差异蛋白,其中124个表现为上调,195个表现为下调。适熟与未熟相比,发现223个差异蛋白质,包括125个上调蛋白和98个下调蛋白。(3)在基因本体(Gene Ontology,GO)功能注释中,差异蛋白质主要参与生物过程(代谢过程、细胞过程)、细胞组成(细胞、细胞组分、细胞器)和分子功能(催化活性)。(4)在京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)功能富集中,差异蛋白质显著富集于代谢途径、光合作用、次生代谢产物的生物合成等。(5)PRM验证发现对比组OM vs IM,OM vs WM和WM vs IM中,分别有10/9/10个蛋白质验证结果与iTRAQ定量表现出相同的趋势。6个差异蛋白包括Q1WL43、A0A1S4DCM1、A0A1S4C433、A0A1S4AKK6、A0A1S3ZQP6、A0A140G1P2可能是烟叶衰老潜在靶标蛋白。【结论】本研究采用iTRAQ 结合PRM 技术,筛选出烟草叶片响应衰老差异表达蛋白,可为深入认识烟草衰老的应答分子调控机制奠定基础。
基金Supported by the National Natural Science Foundation of China(No.61002017 and No.61072076)the STCSM and Shanghai Rising-Star Program(10JC1414400)
文摘In this paper,using cyclostationarity-based sensing method to detect the presence of Orthogonal Frequency Division Multiplexing(OFDM) signal over doubly-selective fading channels is studied.By approximating the channel with Basis Expansion Model(BEM),we derive the second-order cyclostationary statistics of the received OFDM signal over doubly-selective fading channels.Theoretical analysis indicates that new cyclostationary signatures produced by Doppler spread and multipath delay can be further exploited in the detecting process.Simulation examples demonstrate that the sensing methods using channel-induced cyclostationary features provide substantial improvements on detection performance.