Light is a key environmental cue that inhibits hypocotyl cell elongation through the blue and red/far-red light photoreceptors cryptochrome- and phytochrome-mediated pathways in Arabidopsis. In contrast, as a pivotal ...Light is a key environmental cue that inhibits hypocotyl cell elongation through the blue and red/far-red light photoreceptors cryptochrome- and phytochrome-mediated pathways in Arabidopsis. In contrast, as a pivotal endogenous phytohormone auxin promotes hypocotyl elongation through the auxin receptors TIR1/AFBs-mediated degradation of AUX/IAA proteins （AUX/IAAs）. However, the molecular mechanisms underlying the antagonistic interaction of light and auxin signaling remain unclear. Here, we report that light inhibits auxin signaling through stabilization of AUX/IAAs byblue and red light-dependent interactions of cryptochrome 1 （CRY1） and phytochrome B with AUX/IAAs, respectively. Blue light-triggered interactions of CRY1 with AUX/IAAs inhibit the associations of TIR1 with AUX/IAAs, leading to the repression of auxin- induced degradation of these proteins. Our results indicate that photoreceptors share AUX/IAAs with auxin receptors as the same direct downstream signaling components. We propose that antagonistic regulation of AUX/IAA protein stability by photoreceptors and auxin receptors allows plants to balance light and auxin signals to optimize their growth.展开更多
Plants have evolved complex mechanisms to defend themselves against pathogens. It has been shown that several defense responses are influenced by light, and the red/far-red light photoreceptor phytochromes （PHY） mod...Plants have evolved complex mechanisms to defend themselves against pathogens. It has been shown that several defense responses are influenced by light, and the red/far-red light photoreceptor phytochromes （PHY） modulate plant defense responses in Arabidopsis. Blue light receptor cryptochromes （CRY） work together with PHY to regulate many light-controlled responses, including photomorphogenesis, floral induction, and entrainment of the circadian clock. We report here that the Arabidopsis blue light photoreceptor CRY1 positively regulates inducible resistance to Pseudomonas syringae under continuous light conditions. By challenging plants with R syringae pv. tomato （Pst.） DC3000 carrying avrRpt2, we demonstrate that effector-triggered local resistance is down-regulated in the cry1 mutant, leading to more pathogen multiplication. In plants overexpressing CRY1 （CRYl-ovx）, however, local resistance is significantly up-regulated. We also show that systemic acquired resistance （SAR） is positively regulated by CRY1, and that salicylic acid （SA）-induced pathogenesis-related gene PR-1 expression is reduced in the cry1 mutant, but enhanced in CRYl-ovx plants. However, our results in- dicate that CRY1 only modestly influences SA accumulation and has no effect on hypersensitive cell death. These results suggest that CRY1 may positively regulate R protein-mediated resistance to P. syringae with increased PR gene expression.展开更多
Metabolic homeostasis requires dynamic catabolic and anabolic processes. Autophagy, an intracellular lysosomal degradative pathway, can rewire cellular metabolism linking catabolic to anabolic processes and thus susta...Metabolic homeostasis requires dynamic catabolic and anabolic processes. Autophagy, an intracellular lysosomal degradative pathway, can rewire cellular metabolism linking catabolic to anabolic processes and thus sustain homeostasis. This is especially relevant in the liver, a key metabolic organ thatgoverns body energy metabolism. Autophagy’s role in hepatic energy regulation has just begun to emerge and autophagy seems to have a much broader impact than what has been appreciated in the field. Though classically known for selective or bulk degradation of cellular components or energy-dense macromolecules, emerging evidence indicates autophagy selectively regulates various signaling proteins to directly impact the expression levels of metabolic enzymes or their upstream regulators. Hence, we review three specific mechanisms by which autophagy can regulate metabolism: A) nutrient regeneration, B) quality control of organelles, and C) signaling protein regulation. The plasticity of the autophagic function is unraveling a new therapeutic approach. Thus, we will also discuss the potential translation of promising preclinical data on autophagy modulation into therapeutic strategies that can be used in the clinic to treat common metabolic disorders.展开更多
This study aims to explore the effect and mechanism of Jiao-tai-wan （JTW） on systemic and tissue-specific inflammation and insulin resistance in obesity-resistant （OR） rats with chronic partial sleep deprivation ...This study aims to explore the effect and mechanism of Jiao-tai-wan （JTW） on systemic and tissue-specific inflammation and insulin resistance in obesity-resistant （OR） rats with chronic partial sleep deprivation （PSD）. OR rats with PSD were orally given JTW and Estazolam for 4 weeks. The amount of food intake and metabolic parameters such as body weight increase rate, fasting plasma glucose （FPG）, fasting insulin （FINS）, homeostasis model assessment-insulin resistance （HOMA-IR） and plasma inflammatory markers were measured. The expression levels of circadian proteins cryptochrome 1 （Cryl） and cryptochrome 2 （Cry2） in hypothalamus, adipose and liver tissues were also determined. Meanwhile, the mRNA expression of inflammatory markers, activity of nuclear factor kappa B （NF-κB） p65 protein, as well as the expression levels of insulin signaling pathway proteins in hypothalamus, adipose and liver tissues were measured. Additionally, cyclic adenosine 3＇, 5＇-monophosphate （cAMP） and activity of vasodilator-stimulated phosphoprotein （VASP） in hypothalamus tissue were measured. JTW significantly decreased the body weight increase rate and food intake, ameliorated systemic inflammation and insulin resistance. JTW effectively ameliorated inflammation and increased PI3K/AKT signaling activation in hypothalamus, adipose and liver. Interestingly, all these changes were associated with the up-regulation of circadian gene Cryl and Cry2 protein expression. We also found that in hypothalamus tissue of PSD rats, down-regulation of Cryl and Cry2 activated cAMP/PKA signaling and then led to inflammation, while JTW inhibited this signaling. These results suggested that JTW has the beneficial effect on ameliorating inflammation and insulin resistance in partially sleep-deprived rats by up-regulating Cry expression.展开更多
Light and the heterotrimeric G-protein are known to antagonistically regulate photomorphogenesis in Arabidopsis. However, whether light and G-protein coordinate the regulation of photomorphogenesis is largely unknown....Light and the heterotrimeric G-protein are known to antagonistically regulate photomorphogenesis in Arabidopsis. However, whether light and G-protein coordinate the regulation of photomorphogenesis is largely unknown. Here we show that the blue light photoreceptor cryptochrome 1 （CRY1） physically inter-acts with the G-protein β subunit, AGB1, in a blue light-dependent manner. We also show that AGB1 directly interacts with HY5, a basic leucine zipper transcriptional factor that acts as a critical positive regulator of photomorphogenesis, to inhibit its DNA-binding activity. Genetic studies suggest that CRY1 acts partially through AGB1, and AGB1 acts partially through HY5 to regulate photomorphogenesis. Moreover, we demonstrate that blue light-triggered interaction of CRY1 with AGB1 promotes the dissociation of HY5 from AGB1. Our results suggest that the CRY1 signaling mechanism involves positive regulation of the DNA-binding activity of HY5 mediated by the CRY1-AGB1 interaction, which inhibits the association of AGB1 with HY5. We propose that the antagonistic regulation of HY5 DNA-binding activity by CRY1 and AGB1 may allow plants to balance light and G-protein signaling and optimize photomorphogenesis.展开更多
Seedling development including hypocotyl elongation is a critical phase in the plant life cycle. Light regula- tion of hypocotyl elongation is primarily mediated through the blue light photoreceptor cryptochrome and r...Seedling development including hypocotyl elongation is a critical phase in the plant life cycle. Light regula- tion of hypocotyl elongation is primarily mediated through the blue light photoreceptor cryptochrome and red/far-red light photoreceptor phytochrome signaling pathways, comprising regulators including COP1, HY5, and phytochrome- interacting factors （PIFs）. The novel phytohormones, strigolactones, also participate in regulating hypocotyl growth. However, how strigolactone coordinates with light and photoreceptors in the regulation of hypocotyl elongation is largely unclear. Here, we demonstrate that strigolactone inhibition of hypocotyl elongation is dependent on cryp- tochrome and phytochrome signaling pathways. The photoreceptor mutants cry1 cry2, phyA, and phyB are hyposensi- tive to strigolactone analog GR24 under the respective monochromatic light conditions, while cop1 and pifl pif3 pif4 pif5 （pifq） quadruple mutants are hypersensitive to GR24 in darkness. Genetic studies indicate that the enhanced respon- siveness of cop1 to GR24 is dependent on HY5 and MAX2, while that of pifq is independent of HY5. Further studies demonstrate that GR24 constitutively up-regulates HY5 expression in the dark and light, whereas GR24-promoted HY5 protein accumulation is light- and cryptochrome and phytochrome photoreceptor-dependent. These results suggest that the light dependency of strigolactone regulation of hypocotyl elongation is likely mediated through MAX2-dependent promotion of HY5 expression, light-dependent accumulation of HY5, and PIF-regulated components.展开更多
Soybean(Glycine max(L.) Merr.), grown for its plant oils and proteins, is one of the most important crops throughout the world.Generating stable and heritable transgenic soybeans is relatively inefficient;therefore, t...Soybean(Glycine max(L.) Merr.), grown for its plant oils and proteins, is one of the most important crops throughout the world.Generating stable and heritable transgenic soybeans is relatively inefficient;therefore, there is an urgent need for a simple and high-efficient transient transformation method by which to enable the investigation of gene functions in soybeans, which will facilitate the elucidation and improvement of the molecular mechanisms regulating the associated agronomic traits. We established a system of transient expression in soybean mesophyll protoplasts and obtained a high level of protoplast transfection efficiency(up to 83.5%). The subcellular activity of the protoplasts was well preserved, as demonstrated by the dynamic formation of GmCRY nucleus photobodies(NPs) and/or cytoplasmic photobody-like structures(CPs) in response to blue light.In addition, we showed that GmCRY1b CPs colocalized with GmCOP1b, a co-ortholog of Arabidopsis thaliana CONSTITUTIVE PHOTOMORPHOGENIC 1(COP1), which provided new insight into the potential roles of GmCRY1s in the cytoplasm.展开更多
The blue-light receptor cryptochrome 1(CRY1)primarily mediates blue-light inhibition of hypocotyl elongation in Arabidopsis.However,the underlying mechanisms remain largely elusive.We report here that CRY1 inhibits hy...The blue-light receptor cryptochrome 1(CRY1)primarily mediates blue-light inhibition of hypocotyl elongation in Arabidopsis.However,the underlying mechanisms remain largely elusive.We report here that CRY1 inhibits hypocotyl elongation by repressing brassinosteroid(BR)signaling.A genetic interaction assay reveals the negative regulatory effect of CRY1 on the function of BZR1,a core transcription factor in the BR signaling pathway.We demonstrated that CRY1 interacts with the DNA-binding domain of BZR1 to interfere with the DNA-binding ability of BZR1,and represses its transcriptional activity.Furthermore,we found that CRY1 promotes the phosphorylation of BZR1 and inhibits the nuclear accumulation of BZR1.Interestingly,we discovered that CRY1 interacts with the GSK3-like kinase BIN2 and enhances the interaction of BIN2 and BZR1 in a light-dependent manner.Our findings revealed that CRY1 negatively regulates the function of BZR1 through at least two mechanisms:interfering with the DNA-binding ability of BZR1 and promoting the phosphorylation of BZR1.Therefore,we uncover a novel CRY1-BIN2-BZR1 regulatory module that mediates crosstalk between blue light and BR signaling to coordinate plant growth in Arabidopsis.展开更多
Cryptochromes （CRYs） are blue and UV light photoreceptors, known to play key roles in circadian rhythms and in the light-dependent magnetosensitivity of insects. Two novel cryptochrome genes were cloned from the bro...Cryptochromes （CRYs） are blue and UV light photoreceptors, known to play key roles in circadian rhythms and in the light-dependent magnetosensitivity of insects. Two novel cryptochrome genes were cloned from the brown planthopper, and were given the designations of Nlcryl and Nlcry2, with the accession numbers KM108578 and KM108579 in GenBank. The complementary DNA sequences ofNlcryl andNlcry2 are 1935 bp and 2463 bp in length, and they contain an open reading frame of 1629 bp and 1872 bp, encoding amino acids of 542 and 623, with a predicted molecular weight of 62.53 kDa and 70.60 kDa, respectively. Well-conserved motifs such as DNA-photolyase and FAD-binding-7 domains were observed in Nlcry1 and Nlcry2. Phylogenetic analysis demonstrated the proteins of Nlcry1 and Nlcry2 to be clustered into the insect＇s cryptochrome 1 and cryptochrome 2, respectively. Quantitative polymerase chain reaction showed that the daily oscillations of messenger RNA （mRNA） expression in the head of the brown planthopper were mild for Nlcryl, and modest for Nlcry2. Throughout all developmental stages, Nlcryl and Nlcry2 exhibited extreme fluctuations and distinctive expression profiles. Cryptochrome mRNA expression peaked immediately after adult emergence and then decreased subsequently. The tissue expression profiles of newly emerged brown planthopper adults showed higher expression levels of CRYs in the head than in the thorax or abdomen, as well as significantly higher levels of CRYs in the heads of the macropterous strain than in the heads of the brachypterous strain. Taken together, the results of our study suggest that the two cryptochrome genes characterized in the brown planthopper might be associated with developmental physiology and migration.展开更多
Light is a critical environmental cue that regulates a variety of diverse plant developmental processes.Cryptochrome 1(CRY1)is the major photoreceptor that mediates blue light-dependent photomorphogenic responses such...Light is a critical environmental cue that regulates a variety of diverse plant developmental processes.Cryptochrome 1(CRY1)is the major photoreceptor that mediates blue light-dependent photomorphogenic responses such as the inhibition of hypocotyl elongation.Gibberellin(GA)participates in the repression of photomorphogenesis and promotes hypocotyl elongation.However,the antagonistic interaction between blue light and GA is not well understood.Here,we report that blue light represses GA-induced degradation of the DELLA proteins(DELLAs),which are key negative regulators in the GA signaling pathway,via CRY1,thereby inhibiting the GA response during hypocotyl elongation.Both in vitro and in vivo biochemical analyses demonstrated that CRY1 physically interacts with GA receptors-GA-INSENSITIVE DWARF 1 proteins(GID1s)-and DELLAs in a blue light-dependent manner.Furthermore,we showed that CRY1 inhibits the association between GID1s and DELLAs.Genetically,CRY1 antagonizes the function of GID1s to repress the expression of cell elongation-related genes and thus hypocotyl elongation.Taken together,our findings demonstrate that CRY1 coordinates blue light and GA signali ng for plant photomorphogenesis by stabilizing DELLAs through the binding and in activation of GID1s,providing new in sights into the mechanism by which blue light antagonizes the function of GA in photomorphogenesis.展开更多
Soybean is an important legume crop that displays the classic shade avoidance syndrome(SAS),including exaggerated stem elongation,which leads to lodging and yield reduction under density farming conditions.Here,we com...Soybean is an important legume crop that displays the classic shade avoidance syndrome(SAS),including exaggerated stem elongation,which leads to lodging and yield reduction under density farming conditions.Here,we compared the effects of two shade signals,low red light to far-red light ratio(R:FR)and low blue light(LBL),on soybean status and revealed that LBL predominantly induces excessive stem elongation.We used CRISPR-Cas9-engineered Gmcry mutants to investigate the functions of seven cryptochromes(GmCRYs)in soybean and found that the four GmCRY1s overlap in mediating LBL-induced SAS.Lightactivated GmCRY1s increase the abundance of the bZlP transcription factors STF1 and STF2,which directly upregulate the expression of genes encoding GA2 oxidases to deactivate GA1 and repress stem elongation.Notably,GmCRY1b overexpression lines displayed multiple agronomic advantages over the wild-type control under both dense planting and intercropping conditions.Our study demonstrates the integration of GmCRY1-mediated signals with the GA metabolic pathway in the regulation of LBL-induced SAS in soybean.It also provides a promising option for breeding lodging-resistant,high-yield soybean cultivars in the future.展开更多
文摘Light is a key environmental cue that inhibits hypocotyl cell elongation through the blue and red/far-red light photoreceptors cryptochrome- and phytochrome-mediated pathways in Arabidopsis. In contrast, as a pivotal endogenous phytohormone auxin promotes hypocotyl elongation through the auxin receptors TIR1/AFBs-mediated degradation of AUX/IAA proteins （AUX/IAAs）. However, the molecular mechanisms underlying the antagonistic interaction of light and auxin signaling remain unclear. Here, we report that light inhibits auxin signaling through stabilization of AUX/IAAs byblue and red light-dependent interactions of cryptochrome 1 （CRY1） and phytochrome B with AUX/IAAs, respectively. Blue light-triggered interactions of CRY1 with AUX/IAAs inhibit the associations of TIR1 with AUX/IAAs, leading to the repression of auxin- induced degradation of these proteins. Our results indicate that photoreceptors share AUX/IAAs with auxin receptors as the same direct downstream signaling components. We propose that antagonistic regulation of AUX/IAA protein stability by photoreceptors and auxin receptors allows plants to balance light and auxin signals to optimize their growth.
文摘Plants have evolved complex mechanisms to defend themselves against pathogens. It has been shown that several defense responses are influenced by light, and the red/far-red light photoreceptor phytochromes （PHY） modulate plant defense responses in Arabidopsis. Blue light receptor cryptochromes （CRY） work together with PHY to regulate many light-controlled responses, including photomorphogenesis, floral induction, and entrainment of the circadian clock. We report here that the Arabidopsis blue light photoreceptor CRY1 positively regulates inducible resistance to Pseudomonas syringae under continuous light conditions. By challenging plants with R syringae pv. tomato （Pst.） DC3000 carrying avrRpt2, we demonstrate that effector-triggered local resistance is down-regulated in the cry1 mutant, leading to more pathogen multiplication. In plants overexpressing CRY1 （CRYl-ovx）, however, local resistance is significantly up-regulated. We also show that systemic acquired resistance （SAR） is positively regulated by CRY1, and that salicylic acid （SA）-induced pathogenesis-related gene PR-1 expression is reduced in the cry1 mutant, but enhanced in CRYl-ovx plants. However, our results in- dicate that CRY1 only modestly influences SA accumulation and has no effect on hypersensitive cell death. These results suggest that CRY1 may positively regulate R protein-mediated resistance to P. syringae with increased PR gene expression.
基金supported by the Tulane University School of Medicine Endowment Fund(BK,USA)American Society for Investigative Pathology(ASIP/SROPP)(KB&SB,USA)Be HEARD Rare Disease challenge 2020(BK,USA)。
文摘Metabolic homeostasis requires dynamic catabolic and anabolic processes. Autophagy, an intracellular lysosomal degradative pathway, can rewire cellular metabolism linking catabolic to anabolic processes and thus sustain homeostasis. This is especially relevant in the liver, a key metabolic organ thatgoverns body energy metabolism. Autophagy’s role in hepatic energy regulation has just begun to emerge and autophagy seems to have a much broader impact than what has been appreciated in the field. Though classically known for selective or bulk degradation of cellular components or energy-dense macromolecules, emerging evidence indicates autophagy selectively regulates various signaling proteins to directly impact the expression levels of metabolic enzymes or their upstream regulators. Hence, we review three specific mechanisms by which autophagy can regulate metabolism: A) nutrient regeneration, B) quality control of organelles, and C) signaling protein regulation. The plasticity of the autophagic function is unraveling a new therapeutic approach. Thus, we will also discuss the potential translation of promising preclinical data on autophagy modulation into therapeutic strategies that can be used in the clinic to treat common metabolic disorders.
基金This study was supported by National Natural Science Foundation of China （No. 81373871 and No. 81473637）.
文摘This study aims to explore the effect and mechanism of Jiao-tai-wan （JTW） on systemic and tissue-specific inflammation and insulin resistance in obesity-resistant （OR） rats with chronic partial sleep deprivation （PSD）. OR rats with PSD were orally given JTW and Estazolam for 4 weeks. The amount of food intake and metabolic parameters such as body weight increase rate, fasting plasma glucose （FPG）, fasting insulin （FINS）, homeostasis model assessment-insulin resistance （HOMA-IR） and plasma inflammatory markers were measured. The expression levels of circadian proteins cryptochrome 1 （Cryl） and cryptochrome 2 （Cry2） in hypothalamus, adipose and liver tissues were also determined. Meanwhile, the mRNA expression of inflammatory markers, activity of nuclear factor kappa B （NF-κB） p65 protein, as well as the expression levels of insulin signaling pathway proteins in hypothalamus, adipose and liver tissues were measured. Additionally, cyclic adenosine 3＇, 5＇-monophosphate （cAMP） and activity of vasodilator-stimulated phosphoprotein （VASP） in hypothalamus tissue were measured. JTW significantly decreased the body weight increase rate and food intake, ameliorated systemic inflammation and insulin resistance. JTW effectively ameliorated inflammation and increased PI3K/AKT signaling activation in hypothalamus, adipose and liver. Interestingly, all these changes were associated with the up-regulation of circadian gene Cryl and Cry2 protein expression. We also found that in hypothalamus tissue of PSD rats, down-regulation of Cryl and Cry2 activated cAMP/PKA signaling and then led to inflammation, while JTW inhibited this signaling. These results suggested that JTW has the beneficial effect on ameliorating inflammation and insulin resistance in partially sleep-deprived rats by up-regulating Cry expression.
基金This work was supported by The National Natural Science Foundation of China grants to H.-Q.Y. （31530085, 91217307, and 90917014） and to H.L. Lian （31570282 and 31170266）, and the National Key Research and Devel- opment Program of China grant （2017YFA0503800）.
文摘Light and the heterotrimeric G-protein are known to antagonistically regulate photomorphogenesis in Arabidopsis. However, whether light and G-protein coordinate the regulation of photomorphogenesis is largely unknown. Here we show that the blue light photoreceptor cryptochrome 1 （CRY1） physically inter-acts with the G-protein β subunit, AGB1, in a blue light-dependent manner. We also show that AGB1 directly interacts with HY5, a basic leucine zipper transcriptional factor that acts as a critical positive regulator of photomorphogenesis, to inhibit its DNA-binding activity. Genetic studies suggest that CRY1 acts partially through AGB1, and AGB1 acts partially through HY5 to regulate photomorphogenesis. Moreover, we demonstrate that blue light-triggered interaction of CRY1 with AGB1 promotes the dissociation of HY5 from AGB1. Our results suggest that the CRY1 signaling mechanism involves positive regulation of the DNA-binding activity of HY5 mediated by the CRY1-AGB1 interaction, which inhibits the association of AGB1 with HY5. We propose that the antagonistic regulation of HY5 DNA-binding activity by CRY1 and AGB1 may allow plants to balance light and G-protein signaling and optimize photomorphogenesis.
基金grants from the National Natural Science Foundation of China，the National Special Grant for Transgenic Crops，the Science and Technology Commission of the Shanghai Municipality，the Shanghai Leading Academic Discipline Project
文摘Seedling development including hypocotyl elongation is a critical phase in the plant life cycle. Light regula- tion of hypocotyl elongation is primarily mediated through the blue light photoreceptor cryptochrome and red/far-red light photoreceptor phytochrome signaling pathways, comprising regulators including COP1, HY5, and phytochrome- interacting factors （PIFs）. The novel phytohormones, strigolactones, also participate in regulating hypocotyl growth. However, how strigolactone coordinates with light and photoreceptors in the regulation of hypocotyl elongation is largely unclear. Here, we demonstrate that strigolactone inhibition of hypocotyl elongation is dependent on cryp- tochrome and phytochrome signaling pathways. The photoreceptor mutants cry1 cry2, phyA, and phyB are hyposensi- tive to strigolactone analog GR24 under the respective monochromatic light conditions, while cop1 and pifl pif3 pif4 pif5 （pifq） quadruple mutants are hypersensitive to GR24 in darkness. Genetic studies indicate that the enhanced respon- siveness of cop1 to GR24 is dependent on HY5 and MAX2, while that of pifq is independent of HY5. Further studies demonstrate that GR24 constitutively up-regulates HY5 expression in the dark and light, whereas GR24-promoted HY5 protein accumulation is light- and cryptochrome and phytochrome photoreceptor-dependent. These results suggest that the light dependency of strigolactone regulation of hypocotyl elongation is likely mediated through MAX2-dependent promotion of HY5 expression, light-dependent accumulation of HY5, and PIF-regulated components.
基金supported by the National Key Research and Development Plan (2016YFD0101005)the National Natural Science Foundation of China (31871705 and 31422041)the Central Public-Interest Scientific Institution Basal Research Fund (Y2016JC13)
文摘Soybean(Glycine max(L.) Merr.), grown for its plant oils and proteins, is one of the most important crops throughout the world.Generating stable and heritable transgenic soybeans is relatively inefficient;therefore, there is an urgent need for a simple and high-efficient transient transformation method by which to enable the investigation of gene functions in soybeans, which will facilitate the elucidation and improvement of the molecular mechanisms regulating the associated agronomic traits. We established a system of transient expression in soybean mesophyll protoplasts and obtained a high level of protoplast transfection efficiency(up to 83.5%). The subcellular activity of the protoplasts was well preserved, as demonstrated by the dynamic formation of GmCRY nucleus photobodies(NPs) and/or cytoplasmic photobody-like structures(CPs) in response to blue light.In addition, we showed that GmCRY1b CPs colocalized with GmCOP1b, a co-ortholog of Arabidopsis thaliana CONSTITUTIVE PHOTOMORPHOGENIC 1(COP1), which provided new insight into the potential roles of GmCRY1s in the cytoplasm.
文摘The blue-light receptor cryptochrome 1(CRY1)primarily mediates blue-light inhibition of hypocotyl elongation in Arabidopsis.However,the underlying mechanisms remain largely elusive.We report here that CRY1 inhibits hypocotyl elongation by repressing brassinosteroid(BR)signaling.A genetic interaction assay reveals the negative regulatory effect of CRY1 on the function of BZR1,a core transcription factor in the BR signaling pathway.We demonstrated that CRY1 interacts with the DNA-binding domain of BZR1 to interfere with the DNA-binding ability of BZR1,and represses its transcriptional activity.Furthermore,we found that CRY1 promotes the phosphorylation of BZR1 and inhibits the nuclear accumulation of BZR1.Interestingly,we discovered that CRY1 interacts with the GSK3-like kinase BIN2 and enhances the interaction of BIN2 and BZR1 in a light-dependent manner.Our findings revealed that CRY1 negatively regulates the function of BZR1 through at least two mechanisms:interfering with the DNA-binding ability of BZR1 and promoting the phosphorylation of BZR1.Therefore,we uncover a novel CRY1-BIN2-BZR1 regulatory module that mediates crosstalk between blue light and BR signaling to coordinate plant growth in Arabidopsis.
基金We thank the staff in the Beijing READ BIO Bioinformatic Technology Company for their assistance in the phylogenetic inference and bioinformatic analysis of brown planthopper CRY proteins. This research was supported by the Key Program of National Natural Science of China （51037006）, the National Basic Research Program of China ＂973＂ （2010CB126200） and the National Nature Science Foundations of China （31170362, 31272051, 31470454 and 31070755）.
文摘Cryptochromes （CRYs） are blue and UV light photoreceptors, known to play key roles in circadian rhythms and in the light-dependent magnetosensitivity of insects. Two novel cryptochrome genes were cloned from the brown planthopper, and were given the designations of Nlcryl and Nlcry2, with the accession numbers KM108578 and KM108579 in GenBank. The complementary DNA sequences ofNlcryl andNlcry2 are 1935 bp and 2463 bp in length, and they contain an open reading frame of 1629 bp and 1872 bp, encoding amino acids of 542 and 623, with a predicted molecular weight of 62.53 kDa and 70.60 kDa, respectively. Well-conserved motifs such as DNA-photolyase and FAD-binding-7 domains were observed in Nlcry1 and Nlcry2. Phylogenetic analysis demonstrated the proteins of Nlcry1 and Nlcry2 to be clustered into the insect＇s cryptochrome 1 and cryptochrome 2, respectively. Quantitative polymerase chain reaction showed that the daily oscillations of messenger RNA （mRNA） expression in the head of the brown planthopper were mild for Nlcryl, and modest for Nlcry2. Throughout all developmental stages, Nlcryl and Nlcry2 exhibited extreme fluctuations and distinctive expression profiles. Cryptochrome mRNA expression peaked immediately after adult emergence and then decreased subsequently. The tissue expression profiles of newly emerged brown planthopper adults showed higher expression levels of CRYs in the head than in the thorax or abdomen, as well as significantly higher levels of CRYs in the heads of the macropterous strain than in the heads of the brachypterous strain. Taken together, the results of our study suggest that the two cryptochrome genes characterized in the brown planthopper might be associated with developmental physiology and migration.
基金supported by the National Natural Science Foundation of China(no.31171176)the Natural Science Foundation of Hunan Province(no.2020JJ4183)the Basic Research Program of Changsha Municipal Science and Technology(no.kq1901028).
文摘Light is a critical environmental cue that regulates a variety of diverse plant developmental processes.Cryptochrome 1(CRY1)is the major photoreceptor that mediates blue light-dependent photomorphogenic responses such as the inhibition of hypocotyl elongation.Gibberellin(GA)participates in the repression of photomorphogenesis and promotes hypocotyl elongation.However,the antagonistic interaction between blue light and GA is not well understood.Here,we report that blue light represses GA-induced degradation of the DELLA proteins(DELLAs),which are key negative regulators in the GA signaling pathway,via CRY1,thereby inhibiting the GA response during hypocotyl elongation.Both in vitro and in vivo biochemical analyses demonstrated that CRY1 physically interacts with GA receptors-GA-INSENSITIVE DWARF 1 proteins(GID1s)-and DELLAs in a blue light-dependent manner.Furthermore,we showed that CRY1 inhibits the association between GID1s and DELLAs.Genetically,CRY1 antagonizes the function of GID1s to repress the expression of cell elongation-related genes and thus hypocotyl elongation.Taken together,our findings demonstrate that CRY1 coordinates blue light and GA signali ng for plant photomorphogenesis by stabilizing DELLAs through the binding and in activation of GID1s,providing new in sights into the mechanism by which blue light antagonizes the function of GA in photomorphogenesis.
基金This work was partially supported by the National Key Research and Development Plan(2016YFDO100201)the National Transgenic Scienceand Technology Program(2016ZX08010-002)+2 种基金the National Natural Science Foundation of China(31422041,31871705)the Agricultural Scienceand Technology Innovation Program(ASTIP)of the Chinese Academy ofAgricultural Sciencesthe Central Public-Interest Scientific InstitutionBasal Research Fund.
文摘Soybean is an important legume crop that displays the classic shade avoidance syndrome(SAS),including exaggerated stem elongation,which leads to lodging and yield reduction under density farming conditions.Here,we compared the effects of two shade signals,low red light to far-red light ratio(R:FR)and low blue light(LBL),on soybean status and revealed that LBL predominantly induces excessive stem elongation.We used CRISPR-Cas9-engineered Gmcry mutants to investigate the functions of seven cryptochromes(GmCRYs)in soybean and found that the four GmCRY1s overlap in mediating LBL-induced SAS.Lightactivated GmCRY1s increase the abundance of the bZlP transcription factors STF1 and STF2,which directly upregulate the expression of genes encoding GA2 oxidases to deactivate GA1 and repress stem elongation.Notably,GmCRY1b overexpression lines displayed multiple agronomic advantages over the wild-type control under both dense planting and intercropping conditions.Our study demonstrates the integration of GmCRY1-mediated signals with the GA metabolic pathway in the regulation of LBL-induced SAS in soybean.It also provides a promising option for breeding lodging-resistant,high-yield soybean cultivars in the future.
