在植物响应紫外线B(ultraviolet-B,UV-B)的过程中,UV-B光受体UVR8(UV Resistance Locus 8)对植物的光形态建成和生长代谢等过程具有重要调控作用。为探究罗布麻属植物UV-B光受体信息,该研究通过罗布麻(Apocynum venetum)和大麻状罗布麻(...在植物响应紫外线B(ultraviolet-B,UV-B)的过程中,UV-B光受体UVR8(UV Resistance Locus 8)对植物的光形态建成和生长代谢等过程具有重要调控作用。为探究罗布麻属植物UV-B光受体信息,该研究通过罗布麻(Apocynum venetum)和大麻状罗布麻(A.cannabinum)全基因组数据进行UV-B光受体UVR8的筛选与生物信息学分析,同时利用转录组数据分析UV-B胁迫处理下的UVR8基因表达模式。结果表明:(1)罗布麻有6个UVR8基因,大麻状罗布麻有5个UVR8基因,前者分布在1、7、9和11号染色体上,后者分布在1、8和9号染色体上。(2)UVR8蛋白为亲水性稳定蛋白,定位在细胞核,不存在跨膜结构和信号肽,二级结构主要由延伸链、无规则卷曲、α-螺旋和β-转角构成。AvUVR8b和AcUVR8a蛋白三级结构与拟南芥UVR8(AtUVR8)最为类似,并且与小粒咖啡(CaUVR8)和伊德斯种咖啡(CeUVR8)的亲缘关系最近。同时发现罗布麻AvUVR8b和大麻状罗布麻AcUVR8a基因和蛋白结构与AtUVR8基因及蛋白高度相似。(3)当以一定剂量UV-B(17.52 kJ·m~(-2)·d~(-1))处理两种罗布麻植株时,AvUVR8b和AcUVR8a的表达量上调。据此推测在响应UV-B时,AvUVR8b基因在罗布麻中起主要作用,AcUVR8a基因在大麻状罗布麻中起主要作用。(4)顺式作用元件分析结果表明,UVR8的表达受光照、温度、水分、氧气和激素等因素的调控。该研究将为进一步研究罗布麻属UVR8的基因功能奠定基础,同时为解析罗布麻属植物适应UV-B的分子机制提供线索。展开更多
紫外线抗性位点8(UV resistance locus 8,UVR8)编码光受体蛋白,负责UV-B感知和信号转导,被认为参与调控其他的生理反应。文章对UVR8过表达和基因沉默植株的果实进行分析,结果表明:与对照组相比,UVR8过表达转基因番茄果实有着更长的贮藏...紫外线抗性位点8(UV resistance locus 8,UVR8)编码光受体蛋白,负责UV-B感知和信号转导,被认为参与调控其他的生理反应。文章对UVR8过表达和基因沉默植株的果实进行分析,结果表明:与对照组相比,UVR8过表达转基因番茄果实有着更长的贮藏期,其果实硬度显著高于野生型;对UVR8转基因番茄果实的过氧化氢酶(CAT)和过氧化物酶(POD)活性进行测定,结果发现过表达番茄果实的CAT、POD的酶活与野生型相比均显著提高,分别是野生型的2.5、2.3倍,而基因沉默番茄果实的酶活与野生型相比显著下降;同时对脂质过氧化指标的丙二醛(MDA)进行分析,表明每g过表达番茄果实中MDA物质的量有所降低,仅为野生型的1/2,而且每g基因沉默番茄果实中MDA物质的量与野生型相比明显升高。由以上结果可推测,UVR8基因在延长番茄果实采后贮藏期中发挥了作用。展开更多
【目的】获得雨生红球藻中紫外抗性蛋白(Uvresistance locus 8,UVR8)的cDNA序列全长,并进行生物信息分析。【方法】以雨生红球藻为研究对象,通过同源克隆方法获得紫外抗性蛋白UVR8的cDNA序列全长,并通过生物信息手段对其理化性质、蛋白...【目的】获得雨生红球藻中紫外抗性蛋白(Uvresistance locus 8,UVR8)的cDNA序列全长,并进行生物信息分析。【方法】以雨生红球藻为研究对象,通过同源克隆方法获得紫外抗性蛋白UVR8的cDNA序列全长,并通过生物信息手段对其理化性质、蛋白结构及系统进化进行分析。【结果】序列分析表明,HaeUVR8的编码区全长为1554 bp,共编码517个氨基酸,预测理论等电点为5.56,理论分子量为54.31 kD。通过BLASTp分析,与拟南芥中UVR8的相似性达到51%,与莱菌衣藻中UVR8的相似性达到59%。通过蛋白保守结构域分析,HaeUVR8蛋白中存在UVR8蛋白的典型结构域,包括7个叶片螺旋结构和保守的色氨酸残基。系统进化分析表明,高等植物和真核绿藻来源UVR8s有共同祖先。【结论】本研究首次获得雨生红球藻中编码UVR8的基因序列,发现其结构与高等植物UVR8相似,暗示二者可能有相似的作用机制,为雨生红球藻中UVR8的表达、功能研究奠定基础,同时为解析雨生红球藻适应紫外光的分子机制提供线索。展开更多
The phytohormone jasmonate(JA)coordinates stress and growth responses to increase plant survival in unfavorable environments.Although JA can enhance plant UV-B stress tolerance,the mechanisms underlying the interactio...The phytohormone jasmonate(JA)coordinates stress and growth responses to increase plant survival in unfavorable environments.Although JA can enhance plant UV-B stress tolerance,the mechanisms underlying the interaction of UV-B and JA in this response remain unknown.In this study,we demonstrate that the UV RESISTANCE LOCUS 8-TEOSINTE BRANCHED1,Cycloidea and PCF 4-LIPOXYGENASE2(UVR8-TCP4-LOX2)module regulates UV-B tolerance dependent on JA signaling pathway in Arabidopsis thaliana.We show that the nucleus-localized UVR8 physically interacts with TCP4 to increase the DNA-binding activity of TCP4 and upregulate the JA biosynthesis gene LOX2.Furthermore,UVR8 activates the expression of LOX2 in a TCP4-dependent manner.Our genetic analysis also provides evidence that TCP4 acts downstream of UVR8 and upstream of LOX2 to mediate plant responses to UV-B stress.Our results illustrate that the UV-B-dependent interaction of UVR8 and TCP4 serves as an important UVR8-TCP4-LOX2 module,which integrates UV-B radiation and JA signaling and represents a new UVR8 signaling mechanism in plants.展开更多
Plant UV-B responses are mediated by the photoreceptor UV RESISTANCE LOCUS 8 (UVR8). In re-sponse to UV-B irradiation, UVR8 homodimers dissociate into monomers that bind to the E3 ubiquitin ligase CONSTITUTIVE PHOTOMO...Plant UV-B responses are mediated by the photoreceptor UV RESISTANCE LOCUS 8 (UVR8). In re-sponse to UV-B irradiation, UVR8 homodimers dissociate into monomers that bind to the E3 ubiquitin ligase CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1). The in-teraction of the C27 domain in the C-terminal tail of UVR8 with the WD40 domain of COP1 is critical for UV-B sig-naling. However, the function of the last 17 amino acids (C17) of the C-terminus of UVR8, which are adjacent to C27, is unknown, although they are largely conserved in land plants. In this study, we established that Arabidopsis thaliana UVR8 C17 binds to full-length UVR8, but not to COP1, and reduces COP1 binding to the remaining portion of UVR8, including C27. We hypothesized that overexpression of C17 in a wild-type background would have a dominant negative effect on UVR8 activity;however, C17 overexpression caused strong silencing of endogenous UVR8, precluding a detailed analysis. We therefore generated YFP-UVR8N423 transgenic lines, in which C17 was deleted, to examine C17 function in-directly. YFP-UVR8N423 was more active than YFP-UVR8, suggesting that C17 inhibits UV-B signaling by attenuating binding between C27 and COP1. Our study reveals an inhibitory role for UVR8 C17 in fine-tuning UVR8–COP1 interactions during UV-B signaling.展开更多
The plant UV-B photoreceptor UV RESISTANCE LOCUS 8(UVR8)exists as a homodimer in its inactive ground state.Upon UV-B exposure,UVR8monomerizes and interacts with a downstreamkey regulator,theCONSTITUTIVE PHOTOMORPHOGEN...The plant UV-B photoreceptor UV RESISTANCE LOCUS 8(UVR8)exists as a homodimer in its inactive ground state.Upon UV-B exposure,UVR8monomerizes and interacts with a downstreamkey regulator,theCONSTITUTIVE PHOTOMORPHOGENIC 1/SUPPRESSOR OF PHYA(COP1/SPA)E3 ubiquitin ligase complex,to initiate UV-B signaling.Two WD40 proteins,REPRESSOR OF UV-B PHOTOMORPHOGENESIS 1(RUP1)and RUP2 directly interact with monomeric UVR8 and facilitate UVR8 ground state reversion,completing the UVR8 photocycle.Here,we reconstituted the RUP-mediated UVR8 redimerization process in vitro and reported the structure of the RUP2-UVR8^(W285A) complex(2.0A).RUP2 and UVR8^(W285A) formed a heterodimer via two distinct interfaces,designated Interface 1 and 2.The previously characterized Interface 1 is found between the RUP2 WD40 domain and the UVR8 C27 subregion.The newly identified Interface 2 is formed through interactions between the RUP2 WD40 domain and the UVR8 core domain.Disruption of Interface 2 impairedUV-B induced photomorphogenic development in Arabidopsis thaliana.Further biochemical analysis indicated that both interfaces are important for RUP2-UVR8 interactions and RUP2-mediated facilitation of UVR8 redimerization.Our findings suggest that the two-interface-interaction mode is adopted by both RUP2 and COP1 when they interact with UVR8,marking a step forward in understanding the molecular basis that underpins the interactions between UVR8 and its photocycle regulators.展开更多
Plants have evolved and perfected a series of light receptors to feel the light at different bands and regulate the expression, modification and interaction of related genes in plants through signal transduction. So f...Plants have evolved and perfected a series of light receptors to feel the light at different bands and regulate the expression, modification and interaction of related genes in plants through signal transduction. So far, many photoreceptors have been identified in plants, UVR8 has recently been identified as a receptor for UV-B light. This paper cloned a WD40 gene related to UVR8 protein subunit, named RrRUP2, based on the Rosa rugose transcriptome data, using Rosa rugose “Zi zhi” as experimental materials. The full length of cDNA of the gene was obtained by RT-PCR and RACE methods. The total length of this gene is 1173 bp, and it encodes 390 amino acids. After bioinformatics analysis, the molecular formula C3415H5659N1173O1434S313 was predicted;the relative molecular weight was 96129.27 Da;the theoretical isoelectric point PI value was 5.00;and its instability index was 47.06. The total average hydrophobic index was 0.750. In the secondary structure of RrRUP2 protein, there are 10 α-helix, 45 β-helix, 181 Random coil, and 154 Extended strand. Gene Bank Blast results showed that the amino acid sequence encoded by RrRUP2 was more than 90% homologous with the RUP2 protein of Rosa chinensis, Fragaria, Malus, Pyrus, Prunus, Juglans, Arabidopsis and Tobacco, so it can be inferred that the RrRUP2 gene is a WD repeat-containing protein. Regarding to fluorescence quantitative expression analysis of RrRUP2, we find its experssion pattern is corresponded with the accumulation of anthocyanins.展开更多
As one of the most important environmental signals for plants,light plays a profound role in regulating virtually every aspect of plant growth and development.Light signals are perceived by plants via several families...As one of the most important environmental signals for plants,light plays a profound role in regulating virtually every aspect of plant growth and development.Light signals are perceived by plants via several families of photoreceptors,among which phytochromes are responsible for absorbing the red(R)and far-red(FR)wavelengths(600–750 nm),cryptochromes(CRYs)perceive the blue(B)/ultraviolet-A(UV-A)wavelengths(320–500 nm),and UV RESISTANCE LOCUS 8(UVR8)is a recently-characterized UV-B(280–320 nm)photoreceptor.展开更多
文摘紫外线抗性位点8(UV resistance locus 8,UVR8)编码光受体蛋白,负责UV-B感知和信号转导,被认为参与调控其他的生理反应。文章对UVR8过表达和基因沉默植株的果实进行分析,结果表明:与对照组相比,UVR8过表达转基因番茄果实有着更长的贮藏期,其果实硬度显著高于野生型;对UVR8转基因番茄果实的过氧化氢酶(CAT)和过氧化物酶(POD)活性进行测定,结果发现过表达番茄果实的CAT、POD的酶活与野生型相比均显著提高,分别是野生型的2.5、2.3倍,而基因沉默番茄果实的酶活与野生型相比显著下降;同时对脂质过氧化指标的丙二醛(MDA)进行分析,表明每g过表达番茄果实中MDA物质的量有所降低,仅为野生型的1/2,而且每g基因沉默番茄果实中MDA物质的量与野生型相比明显升高。由以上结果可推测,UVR8基因在延长番茄果实采后贮藏期中发挥了作用。
文摘【目的】获得雨生红球藻中紫外抗性蛋白(Uvresistance locus 8,UVR8)的cDNA序列全长,并进行生物信息分析。【方法】以雨生红球藻为研究对象,通过同源克隆方法获得紫外抗性蛋白UVR8的cDNA序列全长,并通过生物信息手段对其理化性质、蛋白结构及系统进化进行分析。【结果】序列分析表明,HaeUVR8的编码区全长为1554 bp,共编码517个氨基酸,预测理论等电点为5.56,理论分子量为54.31 kD。通过BLASTp分析,与拟南芥中UVR8的相似性达到51%,与莱菌衣藻中UVR8的相似性达到59%。通过蛋白保守结构域分析,HaeUVR8蛋白中存在UVR8蛋白的典型结构域,包括7个叶片螺旋结构和保守的色氨酸残基。系统进化分析表明,高等植物和真核绿藻来源UVR8s有共同祖先。【结论】本研究首次获得雨生红球藻中编码UVR8的基因序列,发现其结构与高等植物UVR8相似,暗示二者可能有相似的作用机制,为雨生红球藻中UVR8的表达、功能研究奠定基础,同时为解析雨生红球藻适应紫外光的分子机制提供线索。
基金supported by the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(2019QZKK0502)the National Natural Science Foundation of China(No.32370405).
文摘The phytohormone jasmonate(JA)coordinates stress and growth responses to increase plant survival in unfavorable environments.Although JA can enhance plant UV-B stress tolerance,the mechanisms underlying the interaction of UV-B and JA in this response remain unknown.In this study,we demonstrate that the UV RESISTANCE LOCUS 8-TEOSINTE BRANCHED1,Cycloidea and PCF 4-LIPOXYGENASE2(UVR8-TCP4-LOX2)module regulates UV-B tolerance dependent on JA signaling pathway in Arabidopsis thaliana.We show that the nucleus-localized UVR8 physically interacts with TCP4 to increase the DNA-binding activity of TCP4 and upregulate the JA biosynthesis gene LOX2.Furthermore,UVR8 activates the expression of LOX2 in a TCP4-dependent manner.Our genetic analysis also provides evidence that TCP4 acts downstream of UVR8 and upstream of LOX2 to mediate plant responses to UV-B stress.Our results illustrate that the UV-B-dependent interaction of UVR8 and TCP4 serves as an important UVR8-TCP4-LOX2 module,which integrates UV-B radiation and JA signaling and represents a new UVR8 signaling mechanism in plants.
文摘Plant UV-B responses are mediated by the photoreceptor UV RESISTANCE LOCUS 8 (UVR8). In re-sponse to UV-B irradiation, UVR8 homodimers dissociate into monomers that bind to the E3 ubiquitin ligase CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1). The in-teraction of the C27 domain in the C-terminal tail of UVR8 with the WD40 domain of COP1 is critical for UV-B sig-naling. However, the function of the last 17 amino acids (C17) of the C-terminus of UVR8, which are adjacent to C27, is unknown, although they are largely conserved in land plants. In this study, we established that Arabidopsis thaliana UVR8 C17 binds to full-length UVR8, but not to COP1, and reduces COP1 binding to the remaining portion of UVR8, including C27. We hypothesized that overexpression of C17 in a wild-type background would have a dominant negative effect on UVR8 activity;however, C17 overexpression caused strong silencing of endogenous UVR8, precluding a detailed analysis. We therefore generated YFP-UVR8N423 transgenic lines, in which C17 was deleted, to examine C17 function in-directly. YFP-UVR8N423 was more active than YFP-UVR8, suggesting that C17 inhibits UV-B signaling by attenuating binding between C27 and COP1. Our study reveals an inhibitory role for UVR8 C17 in fine-tuning UVR8–COP1 interactions during UV-B signaling.
基金supported by funds from the National Key R&D Program of China(2018YFA0507700 and 2017YFA0506100)the National Natural Science Foundation of China(31722017,31870753,and 32122011)+1 种基金the Foundation of Hubei Hongshan Laboratory(2021hszd010)the China Postdoctoral Science Foundation(2020M682437 for Ling Ma).
文摘The plant UV-B photoreceptor UV RESISTANCE LOCUS 8(UVR8)exists as a homodimer in its inactive ground state.Upon UV-B exposure,UVR8monomerizes and interacts with a downstreamkey regulator,theCONSTITUTIVE PHOTOMORPHOGENIC 1/SUPPRESSOR OF PHYA(COP1/SPA)E3 ubiquitin ligase complex,to initiate UV-B signaling.Two WD40 proteins,REPRESSOR OF UV-B PHOTOMORPHOGENESIS 1(RUP1)and RUP2 directly interact with monomeric UVR8 and facilitate UVR8 ground state reversion,completing the UVR8 photocycle.Here,we reconstituted the RUP-mediated UVR8 redimerization process in vitro and reported the structure of the RUP2-UVR8^(W285A) complex(2.0A).RUP2 and UVR8^(W285A) formed a heterodimer via two distinct interfaces,designated Interface 1 and 2.The previously characterized Interface 1 is found between the RUP2 WD40 domain and the UVR8 C27 subregion.The newly identified Interface 2 is formed through interactions between the RUP2 WD40 domain and the UVR8 core domain.Disruption of Interface 2 impairedUV-B induced photomorphogenic development in Arabidopsis thaliana.Further biochemical analysis indicated that both interfaces are important for RUP2-UVR8 interactions and RUP2-mediated facilitation of UVR8 redimerization.Our findings suggest that the two-interface-interaction mode is adopted by both RUP2 and COP1 when they interact with UVR8,marking a step forward in understanding the molecular basis that underpins the interactions between UVR8 and its photocycle regulators.
文摘Plants have evolved and perfected a series of light receptors to feel the light at different bands and regulate the expression, modification and interaction of related genes in plants through signal transduction. So far, many photoreceptors have been identified in plants, UVR8 has recently been identified as a receptor for UV-B light. This paper cloned a WD40 gene related to UVR8 protein subunit, named RrRUP2, based on the Rosa rugose transcriptome data, using Rosa rugose “Zi zhi” as experimental materials. The full length of cDNA of the gene was obtained by RT-PCR and RACE methods. The total length of this gene is 1173 bp, and it encodes 390 amino acids. After bioinformatics analysis, the molecular formula C3415H5659N1173O1434S313 was predicted;the relative molecular weight was 96129.27 Da;the theoretical isoelectric point PI value was 5.00;and its instability index was 47.06. The total average hydrophobic index was 0.750. In the secondary structure of RrRUP2 protein, there are 10 α-helix, 45 β-helix, 181 Random coil, and 154 Extended strand. Gene Bank Blast results showed that the amino acid sequence encoded by RrRUP2 was more than 90% homologous with the RUP2 protein of Rosa chinensis, Fragaria, Malus, Pyrus, Prunus, Juglans, Arabidopsis and Tobacco, so it can be inferred that the RrRUP2 gene is a WD repeat-containing protein. Regarding to fluorescence quantitative expression analysis of RrRUP2, we find its experssion pattern is corresponded with the accumulation of anthocyanins.
文摘As one of the most important environmental signals for plants,light plays a profound role in regulating virtually every aspect of plant growth and development.Light signals are perceived by plants via several families of photoreceptors,among which phytochromes are responsible for absorbing the red(R)and far-red(FR)wavelengths(600–750 nm),cryptochromes(CRYs)perceive the blue(B)/ultraviolet-A(UV-A)wavelengths(320–500 nm),and UV RESISTANCE LOCUS 8(UVR8)is a recently-characterized UV-B(280–320 nm)photoreceptor.
