Enhanced UV-B radiation represents a major environmental factor impacting global cereal production.Researchers have explored various approaches to reduce the detrimental impact of UV-B radiation on crops.Recently,engi...Enhanced UV-B radiation represents a major environmental factor impacting global cereal production.Researchers have explored various approaches to reduce the detrimental impact of UV-B radiation on crops.Recently,engineered nanoparticles,particularly cerium oxide nanoparticles(CeO_(2)-NPs),have attracted widespread interest for their ability to boost plant tolerance to a range of abiotic stresses.This study investigates how CeO_(2)-NPs application affects the morphology,physiology,biochemistry,and transcriptomics profiles of wheat seedling roots subjected to enhanced UV-B stress.The findings demonstrate that CeO_(2)-NPs notably promoted root length,fresh and dry weights,and root activity(p<0.05)under enhanced UV-B stress.CeO_(2)-NP treatment reduced the content of hydrogen peroxide<(H_(2)O_(2))and malondialdehyde(MDA)in wheat,alleviating oxidative damage in seedling roots and partially restoring the root phenotype.Under non-UV-B stress conditions,CeO_(2)-NP treatment triggered the difference of 237 transcripts in plants relative to the control group.Under enhanced UV-B stress,CeO_(2)-NP treatment exhibited differentially expressed genes(DEGs)linked to the antioxidant defense mechanism responsible for reactive oxygen species(ROS)scavenging,compared to the non-nanoparticle control.This suggests that ROS scavenging may be a key mechanism by which CeO_(2)-NPs enhance wheat resistance to enhanced UV-B radiation.This study elucidates a potential molecular mechanism through which CeO_(2)nanoparticles may enhance wheat tolerance to UV-B stress.展开更多
The level of ultraviolet-B (UV-B) radiation on the Earth’s surface has increased due to depletion of the ozone layer. Here, we explored the effects of continuous wave He-Ne laser irradiation (632 nm, 5 mW·mm-2, ...The level of ultraviolet-B (UV-B) radiation on the Earth’s surface has increased due to depletion of the ozone layer. Here, we explored the effects of continuous wave He-Ne laser irradiation (632 nm, 5 mW·mm-2, 2 min·d-1) on proliferating-cell nuclear antigen (PCNA) damage repair function of wheat seedlings exposed to enhanced UV-B radiation (10.08 kJ·m-2·d-1) at the early growth stages. Wheat seedlings were irradiated with enhanced UV-B, He-Ne laser treatment or a combination of the two. We explored the transcripts of PCNA in each treatment group using RT-PCR. In addition, total proteins were extracted from the 7-day-old wheat leaves, analyzed by SDS-PAGE and identified by western blot. The results showed that the transcription of PCNA was weakened following UV-B radiation compared to the control. However, when seedlings were subjected to elevated UV-B-damaging radiation followed by He-Ne laser irradiation, the expression of PCNA was signifi-cantly higher than UV-B radiation alone. These results suggest that He-Ne laser has an active role in repairing the UV-B damaging effects. In order to further investigate the function of PCNA, dynamic arrangements of PCNA in wheat root-tip cells were observed with confocal laser scanning microscopy (CLSM). The PCNA was marked fluorescent dimming and strength weakened in en-hanced UV-B radiation (UV-B) compared with the control group (CK) during processing. It shows that PCNA may be involved in the separation of chromosomes.展开更多
Antimicrobial peptides(AMP)are small proteins that play critical roles in host defense against microbe invasion.Many AMPs disrupt the cellular membrane of microbe,while the mechanism of action of AMPs can be very soph...Antimicrobial peptides(AMP)are small proteins that play critical roles in host defense against microbe invasion.Many AMPs disrupt the cellular membrane of microbe,while the mechanism of action of AMPs can be very sophisticated.Solid-state NMR(SSNMR)technique is powerful in characterizing the mechanism of AMPs in vivo and in vitro.This review summarizes the recent advance of SSNMR technique in AMP mechanisms characterization.We highlight the sample preparation approaches,the SSNMR spectroscopic methods,and a number of outstanding examples of AMP mechanisms elucidated via SSNMR spectroscopy.展开更多
The distribution and morphology alterations of microfilaments and microtubules in the mesophyll cells and root-tip cells of wheat seedlings, which had been radiated by enhanced ultraviolet-B (10.08 KJ·m-2·d-...The distribution and morphology alterations of microfilaments and microtubules in the mesophyll cells and root-tip cells of wheat seedlings, which had been radiated by enhanced ultraviolet-B (10.08 KJ·m-2·d-1), were examined through the confocal laser scanning microscope (Model FV1000, Olympus, Japan). Microtubule was labeled with an indirect immunofluorescence staining method, and microfilament was labeled with fluorescein isothiocyanate-phalloidin (FITC-Ph) as probes. The results indicated that microtubules in mesophyll cells, compared with the controls, would be depolymerized significantly, and dispersed randomly showing some spots or short rods in the cytoplasm, under the enhanced UV-B radiation condition. The microtubule bundles tended to be diffused, and the fluorescence intensity of that significantly decreased. The distribution pattern of microfilaments, which usually arranged parallelly in control cells, was broken up by enhanced UV-B radiation. We further investigated the distribution and morphology of microtubules in root-tip cells during every stage of cell division, and found that these aberrant phenomena of microtubules were often associated with abnormal cell division. Our findings suggested that the distribution, morphology and structure of cytoskeleton in mesophyll cells and root-tip cells of wheat seedlings would be affected by enhanced UV-B radiation, which might be related to abnormal cell division caused by enhanced UV-B radiation as an extracellular signal.展开更多
We explored the use of exogenous nitric oxide (NO) on alleviating effects of UV-B light on winter wheat development. Triticum aestivum L. cv. Linyou 7287 seeds were irradiated with UV-B (10.08 kJ·m–2·d–1) ...We explored the use of exogenous nitric oxide (NO) on alleviating effects of UV-B light on winter wheat development. Triticum aestivum L. cv. Linyou 7287 seeds were irradiated with UV-B (10.08 kJ·m–2·d–1) (enhanced UV-B) and watered with either water or 100 μmol·L–1 SNP solution. Plants were also watered with the SNP alone. The results showed that enhanced UV-B produced negative effects on seedling development. Leaf length decreased and seedling biomass dropped significantly compared with the control. Photochemical efficiency (Fv/Fm) dropped, and chlorophyll and carotenoid content as well as the ATPase activity declined. Content of UV-absorbing compounds and activity of the POD increased compared to the control. Application of the SNP, a NO donor partially protected wheat seedlings exposed to elevated UV-B radiation in that their leaf lengths and biomass accumulation were enhanced compared to the UV-B treatment alone. SNP also improved the contents of chlorophyll, carotenoid and UV-absorbing compounds in leaves. ATPase activity was enhanced but no influence on POD activity. Furthermore, the application of SNP alone showed a favorable effect on seedling growth compared with the control.展开更多
To explore the wheat seedling development and physiological responses under copper contamination and enhanced ultraviolet-B (UV-B) irradiation, 10 mg·L-1 CuCl2 solution was irrigated to Triticum aestivum L. cv. L...To explore the wheat seedling development and physiological responses under copper contamination and enhanced ultraviolet-B (UV-B) irradiation, 10 mg·L-1 CuCl2 solution was irrigated to Triticum aestivum L. cv. Linyuan 2069 one day after germination with or without ultraviolet-B (10.08 kJ m-2·d-1) light exposure, respectively. The results showed that Cu2+ and UV-B caused various adverse effects on wheat seedling development. Cu2+ hindered root development by significantly reducing root number, while UV-B dwarfed seedling height and decreased the leaf length. Chlorophyll content and activity of ATPase in thylakoid membrane of wheat leaves dropped significantly under enhanced UV-B while the activity of ATPase in plasma membrane of seedling root was significantly decreased in Cu2+ group. Relative electric conductivity of leaves significantly increased in both Cu2+ and UV-B groups, so did the biomass. We also observed that combined Cu2+ and UV-B showed more adverse effects on wheat seedlings than either of them alone except for root growth.展开更多
Being sessile, plants are continuously exposed to DNA-damaging agents presenting in the environment such as ultraviolet (UV). Sunlight acts as an energy source for photosynthetic plants;hence, avoidance of UV radiatio...Being sessile, plants are continuously exposed to DNA-damaging agents presenting in the environment such as ultraviolet (UV). Sunlight acts as an energy source for photosynthetic plants;hence, avoidance of UV radiations (namely, UV-A, 315 - 400 nm;UV-B, 280 - 315 nm;and UV-C, 1 group: 4.05 kJ•m-2•d-1, B2 group: 10.08 kJ•m-2•d-1, B3 group: 7.05 kJ•m-2•d-1, B4 group: 23.02 kJ•m-2•d-1) treatment wheat, then, explored on the growth of wheat root and wheat root tip cell of chromosome aberration effect. In wheat, root-tip cells were observed with confocal laser scanning microscopy (CLSM), the results showed that low doses of B1 group (4.05 kJ•m-2•d-1) promoted the growth of wheat root and cell mitosis frequency. But high dose of B2 group (10.08 kJ•m-2•d-1), B3 group (17.05 kJ•m-2•d-1), B4 group (23.02 kJ•m-2•d-1) inhibited the growth of wheat root tip, and made crooked growth of wheat root, and inhibited the wheat root tip cell mitotic frequency and processed that induce root tip cells of wheat produce all kinds of aberration of chromosome in the interphase containing “multiple nucleoli nuclei”, “incomplete nuclei”, “long round nuclei”, “bean sprouts nucleus”. In mitosis M period contains “dissociative chromosome”, “chromosome bridge”, “adhesion chromosome”, “multi-bundle divide”, “nuclear anomalies”. After, high doses of enhanced UV-B radiation treatment, most of the cell cycle anomaly concentrated in mitosis interphase. In mitosis M period, with UV-B radiation dose enhanced chromosome aberration rate was on the rise and the aberration types also increasing.展开更多
Metabolic Dysfunction-Associated Steatotic Liver Disease(MASLD)has emerged as a predominant cause of chronic liver disease globally,with its prevalence rising steadily each year.If left untreated,MASLD may progress to...Metabolic Dysfunction-Associated Steatotic Liver Disease(MASLD)has emerged as a predominant cause of chronic liver disease globally,with its prevalence rising steadily each year.If left untreated,MASLD may progress to metabolic dysfunction in associated steatohepatitis(MASH),a more severe condition that can irreversibly advance to liver fibrosis,cirrhosis,and even hepatocyte carcinoma(HCC).Recent studies have illuminated a pivotal link between dysregulated cholesterol metabolism and the pathogenesis and severity of MASLD.This underscores the critical need for a comprehensive exploration of the regulatory mechanisms underlying hepatic cholesterol metabolism in MASLD,as such insights could unveil new therapeutic targets and pave the way for early diagnosis and effective prevention strategies.Cyclocarya paliurus(Batal.)Iljinskaja,a plant known for both medicinal and dietary applications,has demonstrated diverse pharmacological properties,including hypoglycemic,lipid-regulating,and hepatoprotective effects.This study aimed to investigate the hypolipidemic and hepatoprotective activities of Cyclocarya paliurus extract(CCE)in a murine model of MASLD induced by a methionine-choline-deficient(MCD)diet.Simvastatin was employed as a positive control drug,while various doses of CCE were administered to assess its therapeutic potential.Meanwhile,the control and model groups received 0.5%sodium carboxymethyl cellulose(CMC-Na)once daily for 6 weeks.At the end of the treatment period,blood and liver samples were collected for biochemical analysis,histopathological assessment,and gene expression profiling.The findings revealed that CCE significantly reduced serum levels of aspartate aminotransferase(AST)and alanine aminotransferase(ALT)while enhancing the activities of cholinesterase(CHE)and high-density lipoprotein cholesterol(HDL-C).In liver tissues,CCE markedly decreased the levels of total cholesterol(TC)and triglycerides(TG),while simultaneously increasing hepatic HDL-C content.Histological analyses showed notable alleviation of pathological liver damage in CCE-treated mice.Molecular studies further demonstrated that CCE downregulated the expression of key genes and proteins involved in cholesterol synthesis,including SREBP2,LDLR,and HMGCR.Concurrently,it upregulated the expression of genes and proteins related to cholesterol transport,such as ABCG5 and ABCG8.Additionally,CCE mitigated inflammation by improving the expression levels of pro-inflammatory cytokines,including TNF-α and IL-6,and modulated oxidative stress markers,such as NRF2,KEAP1,and NQO1.Protein expression analyses revealed reduced levels of IL-6 and IL-1β,further corroborating its anti-inflammatory effects.In summary,C.paliurus exhibited potent hepatoprotective effects in MCD-induced MASLD mice.These protective mechanisms were closely linked to the upregulation of cholesterol transporters ABCG5/8 and the modulation of sterol regulatory element-binding protein 2(SREBP2).This study highlighted the therapeutic potential of C.paliurus as a promising intervention for MASLD and underscored its role in regulating cholesterol metabolism and mitigating inflammation and oxidative stress.展开更多
基金supported by Graduate Innovation Project of Shanxi Normal University(Grant No.2021Y443).
文摘Enhanced UV-B radiation represents a major environmental factor impacting global cereal production.Researchers have explored various approaches to reduce the detrimental impact of UV-B radiation on crops.Recently,engineered nanoparticles,particularly cerium oxide nanoparticles(CeO_(2)-NPs),have attracted widespread interest for their ability to boost plant tolerance to a range of abiotic stresses.This study investigates how CeO_(2)-NPs application affects the morphology,physiology,biochemistry,and transcriptomics profiles of wheat seedling roots subjected to enhanced UV-B stress.The findings demonstrate that CeO_(2)-NPs notably promoted root length,fresh and dry weights,and root activity(p<0.05)under enhanced UV-B stress.CeO_(2)-NP treatment reduced the content of hydrogen peroxide<(H_(2)O_(2))and malondialdehyde(MDA)in wheat,alleviating oxidative damage in seedling roots and partially restoring the root phenotype.Under non-UV-B stress conditions,CeO_(2)-NP treatment triggered the difference of 237 transcripts in plants relative to the control group.Under enhanced UV-B stress,CeO_(2)-NP treatment exhibited differentially expressed genes(DEGs)linked to the antioxidant defense mechanism responsible for reactive oxygen species(ROS)scavenging,compared to the non-nanoparticle control.This suggests that ROS scavenging may be a key mechanism by which CeO_(2)-NPs enhance wheat resistance to enhanced UV-B radiation.This study elucidates a potential molecular mechanism through which CeO_(2)nanoparticles may enhance wheat tolerance to UV-B stress.
文摘The level of ultraviolet-B (UV-B) radiation on the Earth’s surface has increased due to depletion of the ozone layer. Here, we explored the effects of continuous wave He-Ne laser irradiation (632 nm, 5 mW·mm-2, 2 min·d-1) on proliferating-cell nuclear antigen (PCNA) damage repair function of wheat seedlings exposed to enhanced UV-B radiation (10.08 kJ·m-2·d-1) at the early growth stages. Wheat seedlings were irradiated with enhanced UV-B, He-Ne laser treatment or a combination of the two. We explored the transcripts of PCNA in each treatment group using RT-PCR. In addition, total proteins were extracted from the 7-day-old wheat leaves, analyzed by SDS-PAGE and identified by western blot. The results showed that the transcription of PCNA was weakened following UV-B radiation compared to the control. However, when seedlings were subjected to elevated UV-B-damaging radiation followed by He-Ne laser irradiation, the expression of PCNA was signifi-cantly higher than UV-B radiation alone. These results suggest that He-Ne laser has an active role in repairing the UV-B damaging effects. In order to further investigate the function of PCNA, dynamic arrangements of PCNA in wheat root-tip cells were observed with confocal laser scanning microscopy (CLSM). The PCNA was marked fluorescent dimming and strength weakened in en-hanced UV-B radiation (UV-B) compared with the control group (CK) during processing. It shows that PCNA may be involved in the separation of chromosomes.
基金supported by the National Key Research and Development Program of the Ministry of Science and Technology,People's Republic of China(contract number 2016YFA0501203)the National Natural Science Foundation of China(21874004,31470727)the Interdisciplinary Medicine Seed Fund of Peking University,and the Fundamental Research Funds for the Central University.
文摘Antimicrobial peptides(AMP)are small proteins that play critical roles in host defense against microbe invasion.Many AMPs disrupt the cellular membrane of microbe,while the mechanism of action of AMPs can be very sophisticated.Solid-state NMR(SSNMR)technique is powerful in characterizing the mechanism of AMPs in vivo and in vitro.This review summarizes the recent advance of SSNMR technique in AMP mechanisms characterization.We highlight the sample preparation approaches,the SSNMR spectroscopic methods,and a number of outstanding examples of AMP mechanisms elucidated via SSNMR spectroscopy.
文摘The distribution and morphology alterations of microfilaments and microtubules in the mesophyll cells and root-tip cells of wheat seedlings, which had been radiated by enhanced ultraviolet-B (10.08 KJ·m-2·d-1), were examined through the confocal laser scanning microscope (Model FV1000, Olympus, Japan). Microtubule was labeled with an indirect immunofluorescence staining method, and microfilament was labeled with fluorescein isothiocyanate-phalloidin (FITC-Ph) as probes. The results indicated that microtubules in mesophyll cells, compared with the controls, would be depolymerized significantly, and dispersed randomly showing some spots or short rods in the cytoplasm, under the enhanced UV-B radiation condition. The microtubule bundles tended to be diffused, and the fluorescence intensity of that significantly decreased. The distribution pattern of microfilaments, which usually arranged parallelly in control cells, was broken up by enhanced UV-B radiation. We further investigated the distribution and morphology of microtubules in root-tip cells during every stage of cell division, and found that these aberrant phenomena of microtubules were often associated with abnormal cell division. Our findings suggested that the distribution, morphology and structure of cytoskeleton in mesophyll cells and root-tip cells of wheat seedlings would be affected by enhanced UV-B radiation, which might be related to abnormal cell division caused by enhanced UV-B radiation as an extracellular signal.
文摘We explored the use of exogenous nitric oxide (NO) on alleviating effects of UV-B light on winter wheat development. Triticum aestivum L. cv. Linyou 7287 seeds were irradiated with UV-B (10.08 kJ·m–2·d–1) (enhanced UV-B) and watered with either water or 100 μmol·L–1 SNP solution. Plants were also watered with the SNP alone. The results showed that enhanced UV-B produced negative effects on seedling development. Leaf length decreased and seedling biomass dropped significantly compared with the control. Photochemical efficiency (Fv/Fm) dropped, and chlorophyll and carotenoid content as well as the ATPase activity declined. Content of UV-absorbing compounds and activity of the POD increased compared to the control. Application of the SNP, a NO donor partially protected wheat seedlings exposed to elevated UV-B radiation in that their leaf lengths and biomass accumulation were enhanced compared to the UV-B treatment alone. SNP also improved the contents of chlorophyll, carotenoid and UV-absorbing compounds in leaves. ATPase activity was enhanced but no influence on POD activity. Furthermore, the application of SNP alone showed a favorable effect on seedling growth compared with the control.
文摘To explore the wheat seedling development and physiological responses under copper contamination and enhanced ultraviolet-B (UV-B) irradiation, 10 mg·L-1 CuCl2 solution was irrigated to Triticum aestivum L. cv. Linyuan 2069 one day after germination with or without ultraviolet-B (10.08 kJ m-2·d-1) light exposure, respectively. The results showed that Cu2+ and UV-B caused various adverse effects on wheat seedling development. Cu2+ hindered root development by significantly reducing root number, while UV-B dwarfed seedling height and decreased the leaf length. Chlorophyll content and activity of ATPase in thylakoid membrane of wheat leaves dropped significantly under enhanced UV-B while the activity of ATPase in plasma membrane of seedling root was significantly decreased in Cu2+ group. Relative electric conductivity of leaves significantly increased in both Cu2+ and UV-B groups, so did the biomass. We also observed that combined Cu2+ and UV-B showed more adverse effects on wheat seedlings than either of them alone except for root growth.
文摘Being sessile, plants are continuously exposed to DNA-damaging agents presenting in the environment such as ultraviolet (UV). Sunlight acts as an energy source for photosynthetic plants;hence, avoidance of UV radiations (namely, UV-A, 315 - 400 nm;UV-B, 280 - 315 nm;and UV-C, 1 group: 4.05 kJ•m-2•d-1, B2 group: 10.08 kJ•m-2•d-1, B3 group: 7.05 kJ•m-2•d-1, B4 group: 23.02 kJ•m-2•d-1) treatment wheat, then, explored on the growth of wheat root and wheat root tip cell of chromosome aberration effect. In wheat, root-tip cells were observed with confocal laser scanning microscopy (CLSM), the results showed that low doses of B1 group (4.05 kJ•m-2•d-1) promoted the growth of wheat root and cell mitosis frequency. But high dose of B2 group (10.08 kJ•m-2•d-1), B3 group (17.05 kJ•m-2•d-1), B4 group (23.02 kJ•m-2•d-1) inhibited the growth of wheat root tip, and made crooked growth of wheat root, and inhibited the wheat root tip cell mitotic frequency and processed that induce root tip cells of wheat produce all kinds of aberration of chromosome in the interphase containing “multiple nucleoli nuclei”, “incomplete nuclei”, “long round nuclei”, “bean sprouts nucleus”. In mitosis M period contains “dissociative chromosome”, “chromosome bridge”, “adhesion chromosome”, “multi-bundle divide”, “nuclear anomalies”. After, high doses of enhanced UV-B radiation treatment, most of the cell cycle anomaly concentrated in mitosis interphase. In mitosis M period, with UV-B radiation dose enhanced chromosome aberration rate was on the rise and the aberration types also increasing.
基金National Key Research and Development Program of China(Grant No.2022YFC3501700)the Beijing Municipal Natural Science Foundation(Grant No.7144219).
文摘Metabolic Dysfunction-Associated Steatotic Liver Disease(MASLD)has emerged as a predominant cause of chronic liver disease globally,with its prevalence rising steadily each year.If left untreated,MASLD may progress to metabolic dysfunction in associated steatohepatitis(MASH),a more severe condition that can irreversibly advance to liver fibrosis,cirrhosis,and even hepatocyte carcinoma(HCC).Recent studies have illuminated a pivotal link between dysregulated cholesterol metabolism and the pathogenesis and severity of MASLD.This underscores the critical need for a comprehensive exploration of the regulatory mechanisms underlying hepatic cholesterol metabolism in MASLD,as such insights could unveil new therapeutic targets and pave the way for early diagnosis and effective prevention strategies.Cyclocarya paliurus(Batal.)Iljinskaja,a plant known for both medicinal and dietary applications,has demonstrated diverse pharmacological properties,including hypoglycemic,lipid-regulating,and hepatoprotective effects.This study aimed to investigate the hypolipidemic and hepatoprotective activities of Cyclocarya paliurus extract(CCE)in a murine model of MASLD induced by a methionine-choline-deficient(MCD)diet.Simvastatin was employed as a positive control drug,while various doses of CCE were administered to assess its therapeutic potential.Meanwhile,the control and model groups received 0.5%sodium carboxymethyl cellulose(CMC-Na)once daily for 6 weeks.At the end of the treatment period,blood and liver samples were collected for biochemical analysis,histopathological assessment,and gene expression profiling.The findings revealed that CCE significantly reduced serum levels of aspartate aminotransferase(AST)and alanine aminotransferase(ALT)while enhancing the activities of cholinesterase(CHE)and high-density lipoprotein cholesterol(HDL-C).In liver tissues,CCE markedly decreased the levels of total cholesterol(TC)and triglycerides(TG),while simultaneously increasing hepatic HDL-C content.Histological analyses showed notable alleviation of pathological liver damage in CCE-treated mice.Molecular studies further demonstrated that CCE downregulated the expression of key genes and proteins involved in cholesterol synthesis,including SREBP2,LDLR,and HMGCR.Concurrently,it upregulated the expression of genes and proteins related to cholesterol transport,such as ABCG5 and ABCG8.Additionally,CCE mitigated inflammation by improving the expression levels of pro-inflammatory cytokines,including TNF-α and IL-6,and modulated oxidative stress markers,such as NRF2,KEAP1,and NQO1.Protein expression analyses revealed reduced levels of IL-6 and IL-1β,further corroborating its anti-inflammatory effects.In summary,C.paliurus exhibited potent hepatoprotective effects in MCD-induced MASLD mice.These protective mechanisms were closely linked to the upregulation of cholesterol transporters ABCG5/8 and the modulation of sterol regulatory element-binding protein 2(SREBP2).This study highlighted the therapeutic potential of C.paliurus as a promising intervention for MASLD and underscored its role in regulating cholesterol metabolism and mitigating inflammation and oxidative stress.
