All mammalian metallothionein genes studied to date have several metal responsive elements (MRE) with consensus sequences of TGCRCNC (R, purine) in their regulatory region. MRE-like sequences were also found in many o...All mammalian metallothionein genes studied to date have several metal responsive elements (MRE) with consensus sequences of TGCRCNC (R, purine) in their regulatory region. MRE-like sequences were also found in many other metal-related genes. To see whether there is also such a sequence at the genetic locus (13q14. 3) of Wilson disease, which is a genetic disorder of copper metabolism, junction-trapping method based on the MRE sequence was used. A fragment containing MRE and MRE-like sequences from YAC 27D8 at the WND locus was successfully cloned and mapped back to the YAC by PCR. Presence of such a sequence in the copper transporter gene at the WD locus might imply that it has a possible interesting role in the regulation of WD gene expression.展开更多
The hexanucleotide repeat mutation in the intron-1 of the chromosome 9 open reading frame (C9orf72) is a frequent cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Altered RNA folding pla...The hexanucleotide repeat mutation in the intron-1 of the chromosome 9 open reading frame (C9orf72) is a frequent cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Altered RNA folding plays a role in ALS pathogenesis in two ways: non-ATG translation of the repeat can lead to aggregates of the known C9orf72 specific dipeptide polymer, whereas the repeat also can form neurotoxic RNA inclusions that dose-responsively kill motor neurons. We report the presence of a homology in the 5’untranslated region (UTR) of the messenger RNA encoding C9orf72 with the iron responsive elements (IRE) that control expression of iron-associated transcripts and predict that this RNA structure may iron-dependently regulate C9orf72 translation. We previously report altered serum ferritin levels track with severity of ALS in patients. Here, we conduct bioinformatics analyses to determine the secondary structure of the 5’UTR in C9orf72 mRNA and find it aligned with IREs in the human mitochondrial cis-aconitase and L and H-ferritin transcripts. Comparison of the role of RNA repeats in Friedriech’s ataxia and fragile X mental retardation suggests the utility of RNA based therapies for treatment of ALS. Antisense oligonucleotides (ASO) have been reported to therapeutically target these GGGGCC repeats. At the same time, because the function of C9orf72 is unknown, knockdown strategies carry some risk of inducing or compounding haploinsufficiency. We propose, for consideration, an approach that may enhance its therapeutic dynamic range by increasing the 5’UTR driven translation of C9orf72 protein to compensate for any potential ALS-specific or ASO-induced haploinsufficieny.展开更多
In a recent study published in Nature,Rafei and colleagues identified the transcription factor cAMP responsive element modulator(CREM)as an important regulator in natural killer(NK)cells that have been engineered with...In a recent study published in Nature,Rafei and colleagues identified the transcription factor cAMP responsive element modulator(CREM)as an important regulator in natural killer(NK)cells that have been engineered with Chimeric antigen receptors(CARs).Their study demonstrated that CREM integrates signals from CAR activation and from interleukin-15(IL-15)stimulation and serves as a molecular brake that limits CAR-NK functionality.展开更多
Abscisic acid(ABA)-responsive elements(ABREs)are the major cis-regulatory elements in ABA-induced gene expression.However,the impact of sequence variations on ABRE function is not yet well-understood.Here,we used synt...Abscisic acid(ABA)-responsive elements(ABREs)are the major cis-regulatory elements in ABA-induced gene expression.However,the impact of sequence variations on ABRE function is not yet well-understood.Here,we used synthetic STARR-seq to quantitatively assess the effects of singlenucleotide substitutions on ABRE activity.Our results revealed that the nucleotide substitutions in both the ACGT-core and ACGT-flank regions affected transcriptional strength.Alterations in the ACGT-core sequence had a more significant impact on ABRE activity than changes in the flanking region.Interestingly,we observed that the ACGT-flank variants with high activity exhibited a strong sequence preference in the downstream region,whereas the highly active core variants were diverse in sequence patterns.Our studies provide a quantitative map of ABRE activity at single-nucleotide resolution,which will facilitate the design of ABA-responsive promoters with desired activities in plants.展开更多
AIM: To study the contribution of tonicity response element binding protein(Ton EBP) in retinal ganglion cell(RGC) death of diabetic retinopathy(DR).METHODS: Diabetes was induced in C57BL/6 mice by five consecutive in...AIM: To study the contribution of tonicity response element binding protein(Ton EBP) in retinal ganglion cell(RGC) death of diabetic retinopathy(DR).METHODS: Diabetes was induced in C57BL/6 mice by five consecutive intraperitoneal injections of 55 mg/kg streptozotocin(STZ). Control mice received vehicle(phosphate-buffered saline). All mice were killed 2mo after injections, and the extent of cell death and the protein expression levels of Ton EBP and aldose reductase(AR) were examined.RESULTS: The Ton EBP and AR protein levels and the death of RGC were significantly increased in the retinas of diabetic mice compared with controls 2mo after the induction of diabetes. Terminal deoxynucleotidyl transferase(Td T)-mediated d UTP nick end labeling(TUNEL)-positive signals co-localized with Ton EBP immunoreactive RGC. These changes were increased in the diabetic retinas compared with controls.CONCLUSION: The present data show that AR and Ton EBP are upregulated in the DR and Ton EBP may contribute to apoptosis of RGC in the DR.展开更多
At 8 weeks after intragastric administration of icariin to senescence-accelerated mice （P8 strain）, Morris water maze results showed that escape latency was shortened, and the number of platform crossings was increa...At 8 weeks after intragastric administration of icariin to senescence-accelerated mice （P8 strain）, Morris water maze results showed that escape latency was shortened, and the number of platform crossings was increased. Immunohistochemical staining and western blot assay detected significantly increased levels of cyclic adenosine monophosphate response element binding protein These results suggest that icariin upregulates phosphorylated cyclic adenosine monophosphate response element binding protein levels and improves learning and memory functions in hippocampus of the senescence-accelerated mouse.展开更多
Aim： To characterize the matrix metalloproteinases （MMP）-2 promoter and to identify androgen response elements （AREs） involved in androgen-induced MMP-2 expression. Methods： MMP-2 mRNA levels was determined by r...Aim： To characterize the matrix metalloproteinases （MMP）-2 promoter and to identify androgen response elements （AREs） involved in androgen-induced MMP-2 expression. Methods： MMP-2 mRNA levels was determined by reverse transcription-polymerase chain reaction （RT-PCR）. MMP-2 promoter-driven luciferase assays were used to determine the fragments responsible for androgen-induced activity. Chromatin-immunoprecipitation assay and electrophoretic mobility shift assays （EMSA） were used to verify the identified AREs in the MMP-2 promoter. Results： Androgen significantly induced MMP-2 expression at the mRNA level, which was blocked by the androgen antagonist bicalutamide. Deletion of a region encompassing base pairs -1591 to -1259 （relative to the start codon） of the MMP-2 promoter led to a significant loss of androgen-induced reporter activity. Additional deletion of the 5＇-region up to -562 bp further reduced the androgen-induced MMP-2 promoter activity. Sequence analysis of these two regions revealed two putative ARE motifs. Introducing mutations in the putative ARE motifs by site-directed mutagenesis approach resulted in a dramatic loss of androgen-induced MMP-2 promoter activity, indicating that the putative ARE motifs are required for androgen-stimulated MMP-2 expression. Most importantly, the androgen receptor （AR） interacted with both motif-containing promoter regions in vivo in a chromatin immunoprecipitation assay after androgen treatment. Furthermore, the AR specifically bound to the wild-type but not mutated ARE motifs-containing probes in an in vitro EMSA assay. Conclusion： Two ARE motifs were identified to be responsible for androgen-induced MMP-2 expression in prostate cancer cells.展开更多
BACKGROUND： cAMP-response element binding protein （CREB） is a key modulator of various signaling pathways. CREB activation initiates a series of intracellular signaling pathways that promote neuronal survival. OBJE...BACKGROUND： cAMP-response element binding protein （CREB） is a key modulator of various signaling pathways. CREB activation initiates a series of intracellular signaling pathways that promote neuronal survival. OBJECTIVE： To investigate the regulatory effects of basic fibroblast growth factor （bFGF） on cerebral neuronal CREB expression following ischemia/reperfusion injury. DESIGN, TIME AND SETTING： An immunohistochemical detection experiment was performed at the Department of Anatomy, Shenyang Medical College, between October 2006 and April 2008. MATERIALS： A total of 60 healthy, adult, Wistar rats were randomly divided into three groups： sham-operated （n =12）, ischemia/reperfusion （n = 24）, and bFGF-treated （n = 24）. Rabbit anti-rat CREB （1： 100） and biotin labeled goat anti-rabbit IgG were purchased from the Wuhan Boster Company, China. MetaMorph-evolution MP5.0-BX51 microscopy imaging system was provided by China Medical University, China. METHODS： Rat models of cerebral ischemia/reperfusion injury were developed using the suture method for right middle cerebral artery occlusion. Two-hour ischemia was followed by reperfusion. Rats from the bFGF-treated and ischemia/reperfusion groups were intraperitoneally administered endogenous bFGF （500 IU/mL, 2 000 IU/kg） or an equal amount of physiological saline. Rats from the sham-operated group underwent a similar surgical procedure, without induction of ischemia/reperfusion injury and drug administration. MAIN OUTCOME MEASURES： After 48-hour reperfusion, hippocampal and parietal cortical neuronal CREB expression was detected by immunohistochemistry, and the absorbance of hippocampal CREB-positive products was determined using MetaMorph-evolutionMP5.0-BX51 microscopy imaging system. RESULTS： The sham-operated group exhibited noticeable CREB expression in hippocampal and parietal cortical neurons. In the ischemia/reperfusion group, the CREB expression was discrete and neurons were poorly arranged. The bFGF-treated group exhibited increased CREB expression and better neuronal arrangement compared with the ischemia/reperfusion group. The mean absorbance of CREB-immunoreactive products in the hippocampus and parietal cortex was significantly higher in the ischemia/reperfusion group than in the sham-operated group （P 〈 0.05）, and significantly higher in the bFGF-treated group than in the ischemia/reperfusion group （P 〈 0.05）. CONCLUSION： bFGF significantly upregulates CREB expression in hippocampal and parietal cortical neurons following ischemia/reperfusion injury.展开更多
A dynamic finite element method combined with finite element mixed formula for contact problem is used to analyze the dynamic characteristics of gear system. Considering the stiffness excitation, error excitation and ...A dynamic finite element method combined with finite element mixed formula for contact problem is used to analyze the dynamic characteristics of gear system. Considering the stiffness excitation, error excitation and meshing shock excitation, the dynamic finite element model is established for the entire gear system which includes gears, shafts, bearings and gearbox housing. By the software of I-DEAS, the natural frequency, normal mode, dynamic time-domain response, frequency-domain response and one-third octave velocity grade structure borne noise of gear system are studied by the method of theoretical modal analysis and dynamic response analysis. The maximum values of vibration and structure borne noise are occurred at the mesh frequency of output grade gearing.展开更多
The micro-mechanical response of asphalt mixtures was studied using the discrete element method. The discrete element sample of stone mastic asphalt was generated first and the vehicle load was applied to the sample. ...The micro-mechanical response of asphalt mixtures was studied using the discrete element method. The discrete element sample of stone mastic asphalt was generated first and the vehicle load was applied to the sample. A user-written program was coded with the FISH language in PFC3 D to extract the contact forces within the sample and the displacements of the particles. Then, the contact forces within the whole sample, in asphalt mastic, in coarse aggregates and between asphalt mastic and coarse aggregates were investigated. Finally, the movement of the particles in the sample was analyzed. The sample was divided into 15 areas and a figure was drawn to show how the balls move in each area according to the displacements of the balls in each area. The displacements of asphalt mastic balls and coarse aggregates were also analyzed. The experimental results explain how the asphalt mixture bears vehicle load and the potential reasons why the rutting forms from a micro-mechanical view.展开更多
Thin wail component is utilized to absorb impact energy of a structure. However, the dynamic behavior of such thin-walled structure is highly non-linear with material, geometry and boundary non-linearity. A model upda...Thin wail component is utilized to absorb impact energy of a structure. However, the dynamic behavior of such thin-walled structure is highly non-linear with material, geometry and boundary non-linearity. A model updating and validation procedure is proposed to build accurate finite element model of a frame structure with a non-linear thin-walled component for dynamic analysis. Design of experiments （DOE） and principal component decomposition （PCD） approach are applied to extract dynamic feature from nonlinear impact response for correlation of impact test result and FE model of the non-linear structure. A strain-rate-dependent non-linear model updating method is then developed to build accurate FE model of the structure. Computer simulation and a real frame structure with a highly non-linear thin-walled component are employed to demonstrate the feasibility and effectiveness of the proposed approach.展开更多
BACKGROUND： Neuronal necrosis and apoptosis play important roles in the pathophysiology of cerebral ischemia and resulting cognitive impairment. However, inhibition of neuronal necrosis and apoptosis has been shown t...BACKGROUND： Neuronal necrosis and apoptosis play important roles in the pathophysiology of cerebral ischemia and resulting cognitive impairment. However, inhibition of neuronal necrosis and apoptosis has been shown to attenuate cognitive impairment following cerebral ischemia. OBJECTIVE： To investigate the effects of sevoflurane on cyclic adenosine monophosphate response element binding protein （CREB）, phosphorylated CREB （pCREB）, and Livin expression in the cortex and hippocampus of a rat model of vascular cognitive impairment.DESIGN, TIME AND SETTING： A randomized, controlled experiment was performed in the Chongqing Key Laboratory of Neurology between June 2007 and July 2008.MATERIALS： Sevoflurane was provided by Abbott Laboratory, UK; Morris water maze was provided by Chinese Academy of Medical Sciences, China; goat anti-rat CREB, goat anti-rat pCREB and goat anti-rat Livin antibodies were provided by Biosource International, USA. METHODS： A total of 42 female, Wistar rats were randomly assigned to the following groups： sham operation, vascular cognitive impairment, and sevoflurane treatment. The vascular cognitive impairment rat model was established by permanent bilateral occlusion of both common carotid arteries, and 1.0 MAC sevoflurane was immediately administered by inhalation for 2 hours. MAIN OUTCOME MEASURES： CREB, pCREB, and Livin expression was measured in the cortex and hippocampus by Western blot and reverse transcription-polymerase chain reaction. Behavior was evaluated with Morris water maze. RESULTS： CREB, pCREB, and Livin expression in the sevoflurane treatment group was significantly greater than the vascular cognitive impairment group （P 〈 0.01）. However, expression of CREB and pCREB was significantly less in the sevoflurane treatment and vascular cognitive impairment groups, compared with the sham operation group （P 〈 0.01）. Livin expression in the sevoflurane treatment and vascular cognitive impairment groups was significantly greater than the sham operation group （P 〈 0.01）. Learning, memory, and behavior disorders were observed in the vascular cognitive impairment group. Sevoflurane treatment significantly improved these observed disorders. CONCLUSION： Sevoflurane improved cognitive impairment due to permanent bilateral occlusion of both common carotid arteries. Improved function was associated with increased CREB, pCREB, and Livin expression in the cortex and hippocampus.展开更多
The regulation of hypoxic response elements on the expression of vascular endothelial growth factor （VEGF） gene transfected to primary cultured rat skeletal myoblasts under hypoxic environment was investigated. pEGF...The regulation of hypoxic response elements on the expression of vascular endothelial growth factor （VEGF） gene transfected to primary cultured rat skeletal myoblasts under hypoxic environment was investigated. pEGFP-C3-9HRE-CMV-VEGF vector was constructed with molecular biology technique and transfected to primary cultured rat skeletal myoblasts by lipofectamine in vitro. Gene expression of transfected myoblasts was detected by RT-PCR, Western blot and fluorescence microscope under different oxygen concentrations and different hypoxia time. The results showed that in hypoxia group, the VEGF gene bands were seen and with the decrease of oxygen concentrations and prolongation of hypoxia time, the expression of VEGF mRNA was obviously increased. Under hypoxic environment, the expression of VEGF protein in the transfected myoblasts was significantly increased. EGFP was expressed only under hypoxic environment but not under normoxic environment. It was concluded that hypoxia promoter could be constructed with HRE and regulate the expression of VEGF gene under hypoxic and normoxic environment, which could enhance the re- liability of gene therapy.展开更多
Objective:Gastric cancer(GC)is a globally common cancer characterized by high incidence and mortality worldwide.Advances in the molecular understanding of GC provide promising targets for GC diagnosis and therapy.Long...Objective:Gastric cancer(GC)is a globally common cancer characterized by high incidence and mortality worldwide.Advances in the molecular understanding of GC provide promising targets for GC diagnosis and therapy.Long non-coding RNAs(lncRNAs)and their downstream regulators are regarded to be implicated in the progression of multiple types of malignancies.Studies have shown that the lncRNA small nucleolar RNA host gene 4(SNHG4)serves as a tumor promoter in various malignancies,while its function in GC has yet to be characterized.Therefore,our study aimed to explore the role and underlying mechanism of SNHG4 in GC.Methods:We used qRT-PCR to analyze SNHG4 expression in GC tissues and cells.Kaplan-Meier analysis was used to assess the correlation between SNHG4 expression and the survival rate of GC patients.Cellular function experiments such as CCK-8,BrdU,colony formation,flow cytometry analysis,and transwell were performed to explore the effects of SNHG4 on GC cell proliferation,apoptosis,cell cycle,migration,and invasion.We also established xenograft mouse models to explore the effect of SNHG4 on GC tumor growth.Mechanically,dual luciferase reporter assay was used to verify the interaction between SNHG4 and miR-409-3p and between miR-409-3p and cAMP responsive element binding protein 1(CREB1).Results:The results indicated that SNHG4 was overexpressed in GC tissues and cell lines,and was linked with poor survival rate of GC patients.SNHG4 promoted GC cell proliferation,migration,and invasion while inhibiting cell apoptosis and cell cycle arrest in vitro.The in vivo experiment indicated that SNHG4 facilitated GC tumor growth.Furthermore,SNHG4 was demonstrated to bind to miR-409-3p.Moreover,CREB1 was directly targeted by miR-409-3p.Rescue assays demonstrated that miR-409-3p deficiency reversed the suppressive impact of SNHG4 knockdown on GC cell malignancy.Additionally,miR-409-3p was also revealed to inhibit GC cell proliferation,migration,and invasion by targeting CREB1.Conclusion:In conclusion,we verified that the SNHG4 promoted GC growth and metastasis by binding to miR-409-3p to upregulate CREB1,which may deepen the understanding of the underlying mechanism in GC development.展开更多
The copper-regulated gene expression system has been developed to control spacial and temporal expression of transgene in plant. It comprises two parts: (1) ace I gene encoding copper-responsive transcription factor u...The copper-regulated gene expression system has been developed to control spacial and temporal expression of transgene in plant. It comprises two parts: (1) ace I gene encoding copper-responsive transcription factor under the control of a constitutive or organ-specific promoter, and (2) a gene of interest under the control of a chimeric promoter consisting of the CaMV 35S (-90 to +8) promoter linked to the metal responsive element (MRE) carrying activating copper-metallothionein expression (ACE1)-binding sites. Here, the effectiveness of two different ACE1-binding cis -elements which derive from 5'-regulatory region of yeast metallothionein gene was investigated in transgenic tobacco (Nicotiana tabacum L. cv. W38). The results revealed that the MRE (-210 to -126) could increase the system inducibility by 50% - 100% compared with the previously reported MRE (-148 to -105). It is potential to use the copper-inducible system to control valuable gene traits in plant biotechnology.展开更多
Objective To explore the role of the extracellular signal-regulated kinase （ERK）/cAMP response element binding protein （CREB） pathway in the induction of long-term potentiation （LTP） in the anterior cingulate co...Objective To explore the role of the extracellular signal-regulated kinase （ERK）/cAMP response element binding protein （CREB） pathway in the induction of long-term potentiation （LTP） in the anterior cingulate cortex （ACC） that may be implicated in pain-related negative emotion. Methods LTP of field potential was recorded in ACC slice and the expressions of phospho-ERK （pERK） and phospho-CREB （pCREB） were examined using immunohistochemistry method. Results LTP could be induced stably in ACC slice by high frequency stimulation （2-train, 100 Hz, 1 s）, while APv （an antagonist of NMDA receptor） could block the induction of LTP in the ACC, indicating that LTP in this experiment was NMDA receptor-dependent. Bath application of PD98059 （50 μmol/L）, a selective MEK inhibitor, at 30 min before tetanic stimulation could completely block the induction of LTP. Moreover, the protein level of pERK in the ACC was transiently increased after LTP induction, starting at 5 rain and returning to basal at 1 h after tetanic stimulation. The protein level of pCREB was also increased after LTP induction. The up-regulation in pERK and pCREB expressions could be blocked by pretreatment of PD98059. Double immunostaining showed that after LTP induction, most pERK was co-localized with pCREB. Conclusion NMDA receptor and ERK-CREB pathway are necessary for the induction of LTP in rat ACC and may play important roles in pain emotion.展开更多
AIM:To study the role of hepcidin in hereditary hyperferritinemia cataract syndrome(HHCS). METHODS:Six patients from two families with HHCS, confirmed by genetic analysis showing A to G mutation at position+40 in the ...AIM:To study the role of hepcidin in hereditary hyperferritinemia cataract syndrome(HHCS). METHODS:Six patients from two families with HHCS, confirmed by genetic analysis showing A to G mutation at position+40 in the L-ferritin gene,were recruited to undergo serum hepcidin and prohepcidin measurements using radioimmunoassay and enzyme linked immunoassay,respectively,and measurements were compared with levels in serum from 25 healthy volunteers(14 females),mean age 36±11.9 years.RESULTS:The serum hepcidin and prohepcidin levels in patients with HHCS were 19.1±18.6 and 187± 120.9 ng/mL,respectively.Serum ferritin was 1716.3± 376μg/L.Liver biopsy in one patient did not show any evidence of iron overload.Serum hepcidin and prohepcidin values in healthy controls(HCs)were 15.30±15.71 and 236.88±83.68 ng/mL,respectively,while serum ferritin was 110±128.08μg/L.There was no statistical difference in serum hepcidin level between the two cohorts(19.1±18.6 ng/mL vs 15.30±15.71 ng/mL,P= 0.612)using two-tailed t-test. CONCLUSION:Serum hepcidin levels in HHCS patients is similar to that in HCs.Our study suggests that circulating ferritin is not a factor influencing hepcidin synthesis and does not have a role in the iron-sensing mechanism in hepatocytes.展开更多
We intraperitoneally injected 10 and 50 mg/kg of propofol for 7 consecutive days to treat a rat model of chronic cerebral ischemia. A low-dose of propofol promoted the expression of brain-derived neurotrophic factor, ...We intraperitoneally injected 10 and 50 mg/kg of propofol for 7 consecutive days to treat a rat model of chronic cerebral ischemia. A low-dose of propofol promoted the expression of brain-derived neurotrophic factor, tyrosine kinase receptor B, phosphorylated cAMP response element binding protein, and cAMP in the hippocampus of aged rats with chronic cerebral ischemia, but a high-dose of propofol inhibited their expression. Results indicated that the protective effect of propofol against cerebral ischemia in aged rats is related to changes in the expression of brain-derived neurotrophic factor and tyrosine kinase receptor B in the hippocampus, and that the cAMP-cAMP responsive element binding protein pathway is involved in the regulatory effect of propofol on brain-derived neurotrophic factor expression.展开更多
Objective:To investigate the regulatory role of cyclic adenosine monophosphate responsive element binding protein(CREB)/brain-derived neurotrophic factor(BDNF)signaling pathway in acute sleep deprivation(SD)-induced a...Objective:To investigate the regulatory role of cyclic adenosine monophosphate responsive element binding protein(CREB)/brain-derived neurotrophic factor(BDNF)signaling pathway in acute sleep deprivation(SD)-induced anxiety-like behavior mice(SD group)to study the mechanism of anxiety-like behavior better.Methods:The SD chamber was used to deprive the mice of sleep,and the anxiety-like behavior of the mice was verified using an open field test(OFT),elevated plus maze(EPM),forced swim test(FST),and tail suspension test(TST).Finally,proteins were detected by Western blotting.Result:OFT showed that the active distance and the time of stay in the central area were significantly reduced(P<0.05).EPM showed that the time and number of open arms in the SD group were significantly lower than in the control group(P<0.05).The FST showed that the forced swimming immobility time of the SD group was significantly lower than that of the control(P<0.05).Moreover,the TST showed that the immobility time of the tail suspension experiment in the SD group was significantly higher than that in the control group(P<0.05).Conclusion:Acute SD can regulate anxiety-like behavior in mice through the CREB/BDNF signaling pathway.展开更多
Drought is a major environmental factor limiting cotton (Gossypium hirsutum L.) productivity worldwide and projected climate changes could increase their negative effects in the future. Thus, targeting the molecular m...Drought is a major environmental factor limiting cotton (Gossypium hirsutum L.) productivity worldwide and projected climate changes could increase their negative effects in the future. Thus, targeting the molecular mechanisms correlated with drought tolerance without reducing productivity is a challenge for plant breeding. In this way, we evaluated the effects of water deficit progress on AtDREB2A-CA transgenic cotton plant responses, driven by the stress-inducible rd29 promoter. Besides shoot and root morphometric traits, gas exchange and osmotic adjustment analyses were also included. Here, we present how altered root traits shown by transgenic plants impacted on physiological acclimation responses when submitted to severe water stress. The integration of AtDREB2A-CA into the cotton genome increased total root volume, surface area and total root length, without negatively affecting shoot morphometric growth parameters and nor phenotypic evaluated traits. Additionally, when compared to wild-type plants, transgenic plants (17-T0 plants and its progeny) highlighted a gradual pattern of phenotypic plasticity tosome photosynthetic parameters such as photosynthetic rate and stomatal conductance with water deficit progress. Transgene also promoted greater shoot development and root robustness (greater and deeper root mass) allowing roots to grow into deeper soil layers. The same morpho-physiological trend was observed in the subsequent generation (17.6-T2). Our results suggest that the altered root traits shown by transgenic plants are the major contributors to higher tolerance response, allowing the AtDRE2A-CA-cotton plants to maintain elevated stomatal conductance and assimilate rates and, consequently, reducing their metabolic costs involved in the antioxidant responses activation. These results also suggest that these morpho-physiological changes increased the number of reproductive structures retained per plant (26% higher) when compared with its non-transgenic counterpart. This is the first report of cotton plants overexpressing the AtDRE2A-CA transcription factor, demonstrating a morpho-physiological and yield advantages under drought stress, without displaying any yield penalty under irrigated conditions. The mechanisms by which the root traits influenced the acclimation of the transgenic plants to severe water deficit conditions are also discussed. These data present an opportunity to use this strategy in cotton breeding programs in order to improve drought adaptation toward better rooting features.展开更多
基金The sequence described in this paper has been deposited in Gen-Bank with the accession number U90431. This work was supporte
文摘All mammalian metallothionein genes studied to date have several metal responsive elements (MRE) with consensus sequences of TGCRCNC (R, purine) in their regulatory region. MRE-like sequences were also found in many other metal-related genes. To see whether there is also such a sequence at the genetic locus (13q14. 3) of Wilson disease, which is a genetic disorder of copper metabolism, junction-trapping method based on the MRE sequence was used. A fragment containing MRE and MRE-like sequences from YAC 27D8 at the WND locus was successfully cloned and mapped back to the YAC by PCR. Presence of such a sequence in the copper transporter gene at the WD locus might imply that it has a possible interesting role in the regulation of WD gene expression.
文摘The hexanucleotide repeat mutation in the intron-1 of the chromosome 9 open reading frame (C9orf72) is a frequent cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Altered RNA folding plays a role in ALS pathogenesis in two ways: non-ATG translation of the repeat can lead to aggregates of the known C9orf72 specific dipeptide polymer, whereas the repeat also can form neurotoxic RNA inclusions that dose-responsively kill motor neurons. We report the presence of a homology in the 5’untranslated region (UTR) of the messenger RNA encoding C9orf72 with the iron responsive elements (IRE) that control expression of iron-associated transcripts and predict that this RNA structure may iron-dependently regulate C9orf72 translation. We previously report altered serum ferritin levels track with severity of ALS in patients. Here, we conduct bioinformatics analyses to determine the secondary structure of the 5’UTR in C9orf72 mRNA and find it aligned with IREs in the human mitochondrial cis-aconitase and L and H-ferritin transcripts. Comparison of the role of RNA repeats in Friedriech’s ataxia and fragile X mental retardation suggests the utility of RNA based therapies for treatment of ALS. Antisense oligonucleotides (ASO) have been reported to therapeutically target these GGGGCC repeats. At the same time, because the function of C9orf72 is unknown, knockdown strategies carry some risk of inducing or compounding haploinsufficiency. We propose, for consideration, an approach that may enhance its therapeutic dynamic range by increasing the 5’UTR driven translation of C9orf72 protein to compensate for any potential ALS-specific or ASO-induced haploinsufficieny.
基金supported by interdisciplinary center for clinical research(IZKF)of the medical faculty of the RWTH Aachen(IZKF grant PTD 1-7)by START grant(692535AZ 019/25)funding enabled and organized by Projekt DEAL.
文摘In a recent study published in Nature,Rafei and colleagues identified the transcription factor cAMP responsive element modulator(CREM)as an important regulator in natural killer(NK)cells that have been engineered with Chimeric antigen receptors(CARs).Their study demonstrated that CREM integrates signals from CAR activation and from interleukin-15(IL-15)stimulation and serves as a molecular brake that limits CAR-NK functionality.
基金National Natural Science Foundation of China,Grant/Award Number:32270686。
文摘Abscisic acid(ABA)-responsive elements(ABREs)are the major cis-regulatory elements in ABA-induced gene expression.However,the impact of sequence variations on ABRE function is not yet well-understood.Here,we used synthetic STARR-seq to quantitatively assess the effects of singlenucleotide substitutions on ABRE activity.Our results revealed that the nucleotide substitutions in both the ACGT-core and ACGT-flank regions affected transcriptional strength.Alterations in the ACGT-core sequence had a more significant impact on ABRE activity than changes in the flanking region.Interestingly,we observed that the ACGT-flank variants with high activity exhibited a strong sequence preference in the downstream region,whereas the highly active core variants were diverse in sequence patterns.Our studies provide a quantitative map of ABRE activity at single-nucleotide resolution,which will facilitate the design of ABA-responsive promoters with desired activities in plants.
基金Supported by the Basic Research Program of the Korea Science & Engineering Foundation (No. 2009-0068732)the Basic Research Program of the National Research Foundation of Korea (No.2011-0020163)+1 种基金the Bio-Industry Technology Development Program funded by the Korea Institute of Planning & Evaluation for Technology in Food, Agriculture Forestry & Fisheries (No.112005-3)the BK21 Program and by the MRC program of KRF (R13-2005-012-01001-1)
文摘AIM: To study the contribution of tonicity response element binding protein(Ton EBP) in retinal ganglion cell(RGC) death of diabetic retinopathy(DR).METHODS: Diabetes was induced in C57BL/6 mice by five consecutive intraperitoneal injections of 55 mg/kg streptozotocin(STZ). Control mice received vehicle(phosphate-buffered saline). All mice were killed 2mo after injections, and the extent of cell death and the protein expression levels of Ton EBP and aldose reductase(AR) were examined.RESULTS: The Ton EBP and AR protein levels and the death of RGC were significantly increased in the retinas of diabetic mice compared with controls 2mo after the induction of diabetes. Terminal deoxynucleotidyl transferase(Td T)-mediated d UTP nick end labeling(TUNEL)-positive signals co-localized with Ton EBP immunoreactive RGC. These changes were increased in the diabetic retinas compared with controls.CONCLUSION: The present data show that AR and Ton EBP are upregulated in the DR and Ton EBP may contribute to apoptosis of RGC in the DR.
文摘At 8 weeks after intragastric administration of icariin to senescence-accelerated mice （P8 strain）, Morris water maze results showed that escape latency was shortened, and the number of platform crossings was increased. Immunohistochemical staining and western blot assay detected significantly increased levels of cyclic adenosine monophosphate response element binding protein These results suggest that icariin upregulates phosphorylated cyclic adenosine monophosphate response element binding protein levels and improves learning and memory functions in hippocampus of the senescence-accelerated mouse.
基金Acknowledgment We thank Dr Etty N. Benveniste （University of Alabama at Birmingham, Birmingham, AL, USA） for the truncated MMP-2 promoter-driven luciferase constructs and Ms Donna Barnes for excellent secretarial assistance. This study was supported by KU William L.Valk Endowment and Kansas Mason＇s Foundation, and a grant from KUMC Lied Foundation to Dr Ben-Yi Li. This study was also partially supported by grants from the National Natural Science Foundation of China （No. 30370509 and No. 30370645） to Dr Ping-Yi Xu.
文摘Aim： To characterize the matrix metalloproteinases （MMP）-2 promoter and to identify androgen response elements （AREs） involved in androgen-induced MMP-2 expression. Methods： MMP-2 mRNA levels was determined by reverse transcription-polymerase chain reaction （RT-PCR）. MMP-2 promoter-driven luciferase assays were used to determine the fragments responsible for androgen-induced activity. Chromatin-immunoprecipitation assay and electrophoretic mobility shift assays （EMSA） were used to verify the identified AREs in the MMP-2 promoter. Results： Androgen significantly induced MMP-2 expression at the mRNA level, which was blocked by the androgen antagonist bicalutamide. Deletion of a region encompassing base pairs -1591 to -1259 （relative to the start codon） of the MMP-2 promoter led to a significant loss of androgen-induced reporter activity. Additional deletion of the 5＇-region up to -562 bp further reduced the androgen-induced MMP-2 promoter activity. Sequence analysis of these two regions revealed two putative ARE motifs. Introducing mutations in the putative ARE motifs by site-directed mutagenesis approach resulted in a dramatic loss of androgen-induced MMP-2 promoter activity, indicating that the putative ARE motifs are required for androgen-stimulated MMP-2 expression. Most importantly, the androgen receptor （AR） interacted with both motif-containing promoter regions in vivo in a chromatin immunoprecipitation assay after androgen treatment. Furthermore, the AR specifically bound to the wild-type but not mutated ARE motifs-containing probes in an in vitro EMSA assay. Conclusion： Two ARE motifs were identified to be responsible for androgen-induced MMP-2 expression in prostate cancer cells.
基金Scientific Research Foundation of Liaoning Provincial Education Department for Higher Education Institutions, No.05L442
文摘BACKGROUND： cAMP-response element binding protein （CREB） is a key modulator of various signaling pathways. CREB activation initiates a series of intracellular signaling pathways that promote neuronal survival. OBJECTIVE： To investigate the regulatory effects of basic fibroblast growth factor （bFGF） on cerebral neuronal CREB expression following ischemia/reperfusion injury. DESIGN, TIME AND SETTING： An immunohistochemical detection experiment was performed at the Department of Anatomy, Shenyang Medical College, between October 2006 and April 2008. MATERIALS： A total of 60 healthy, adult, Wistar rats were randomly divided into three groups： sham-operated （n =12）, ischemia/reperfusion （n = 24）, and bFGF-treated （n = 24）. Rabbit anti-rat CREB （1： 100） and biotin labeled goat anti-rabbit IgG were purchased from the Wuhan Boster Company, China. MetaMorph-evolution MP5.0-BX51 microscopy imaging system was provided by China Medical University, China. METHODS： Rat models of cerebral ischemia/reperfusion injury were developed using the suture method for right middle cerebral artery occlusion. Two-hour ischemia was followed by reperfusion. Rats from the bFGF-treated and ischemia/reperfusion groups were intraperitoneally administered endogenous bFGF （500 IU/mL, 2 000 IU/kg） or an equal amount of physiological saline. Rats from the sham-operated group underwent a similar surgical procedure, without induction of ischemia/reperfusion injury and drug administration. MAIN OUTCOME MEASURES： After 48-hour reperfusion, hippocampal and parietal cortical neuronal CREB expression was detected by immunohistochemistry, and the absorbance of hippocampal CREB-positive products was determined using MetaMorph-evolutionMP5.0-BX51 microscopy imaging system. RESULTS： The sham-operated group exhibited noticeable CREB expression in hippocampal and parietal cortical neurons. In the ischemia/reperfusion group, the CREB expression was discrete and neurons were poorly arranged. The bFGF-treated group exhibited increased CREB expression and better neuronal arrangement compared with the ischemia/reperfusion group. The mean absorbance of CREB-immunoreactive products in the hippocampus and parietal cortex was significantly higher in the ischemia/reperfusion group than in the sham-operated group （P 〈 0.05）, and significantly higher in the bFGF-treated group than in the ischemia/reperfusion group （P 〈 0.05）. CONCLUSION： bFGF significantly upregulates CREB expression in hippocampal and parietal cortical neurons following ischemia/reperfusion injury.
基金Funded by the Natural Science Foundation of China (No. 50675232)the Natural Science Foundation of CQ CSTC (2006BB3008)
文摘A dynamic finite element method combined with finite element mixed formula for contact problem is used to analyze the dynamic characteristics of gear system. Considering the stiffness excitation, error excitation and meshing shock excitation, the dynamic finite element model is established for the entire gear system which includes gears, shafts, bearings and gearbox housing. By the software of I-DEAS, the natural frequency, normal mode, dynamic time-domain response, frequency-domain response and one-third octave velocity grade structure borne noise of gear system are studied by the method of theoretical modal analysis and dynamic response analysis. The maximum values of vibration and structure borne noise are occurred at the mesh frequency of output grade gearing.
基金Funded by the National Natural Science Foundation of China(Nos.51108237 and 51178112)
文摘The micro-mechanical response of asphalt mixtures was studied using the discrete element method. The discrete element sample of stone mastic asphalt was generated first and the vehicle load was applied to the sample. A user-written program was coded with the FISH language in PFC3 D to extract the contact forces within the sample and the displacements of the particles. Then, the contact forces within the whole sample, in asphalt mastic, in coarse aggregates and between asphalt mastic and coarse aggregates were investigated. Finally, the movement of the particles in the sample was analyzed. The sample was divided into 15 areas and a figure was drawn to show how the balls move in each area according to the displacements of the balls in each area. The displacements of asphalt mastic balls and coarse aggregates were also analyzed. The experimental results explain how the asphalt mixture bears vehicle load and the potential reasons why the rutting forms from a micro-mechanical view.
基金National Natural Science Foundation of China(No.50575101).
文摘Thin wail component is utilized to absorb impact energy of a structure. However, the dynamic behavior of such thin-walled structure is highly non-linear with material, geometry and boundary non-linearity. A model updating and validation procedure is proposed to build accurate finite element model of a frame structure with a non-linear thin-walled component for dynamic analysis. Design of experiments （DOE） and principal component decomposition （PCD） approach are applied to extract dynamic feature from nonlinear impact response for correlation of impact test result and FE model of the non-linear structure. A strain-rate-dependent non-linear model updating method is then developed to build accurate FE model of the structure. Computer simulation and a real frame structure with a highly non-linear thin-walled component are employed to demonstrate the feasibility and effectiveness of the proposed approach.
文摘BACKGROUND： Neuronal necrosis and apoptosis play important roles in the pathophysiology of cerebral ischemia and resulting cognitive impairment. However, inhibition of neuronal necrosis and apoptosis has been shown to attenuate cognitive impairment following cerebral ischemia. OBJECTIVE： To investigate the effects of sevoflurane on cyclic adenosine monophosphate response element binding protein （CREB）, phosphorylated CREB （pCREB）, and Livin expression in the cortex and hippocampus of a rat model of vascular cognitive impairment.DESIGN, TIME AND SETTING： A randomized, controlled experiment was performed in the Chongqing Key Laboratory of Neurology between June 2007 and July 2008.MATERIALS： Sevoflurane was provided by Abbott Laboratory, UK; Morris water maze was provided by Chinese Academy of Medical Sciences, China; goat anti-rat CREB, goat anti-rat pCREB and goat anti-rat Livin antibodies were provided by Biosource International, USA. METHODS： A total of 42 female, Wistar rats were randomly assigned to the following groups： sham operation, vascular cognitive impairment, and sevoflurane treatment. The vascular cognitive impairment rat model was established by permanent bilateral occlusion of both common carotid arteries, and 1.0 MAC sevoflurane was immediately administered by inhalation for 2 hours. MAIN OUTCOME MEASURES： CREB, pCREB, and Livin expression was measured in the cortex and hippocampus by Western blot and reverse transcription-polymerase chain reaction. Behavior was evaluated with Morris water maze. RESULTS： CREB, pCREB, and Livin expression in the sevoflurane treatment group was significantly greater than the vascular cognitive impairment group （P 〈 0.01）. However, expression of CREB and pCREB was significantly less in the sevoflurane treatment and vascular cognitive impairment groups, compared with the sham operation group （P 〈 0.01）. Livin expression in the sevoflurane treatment and vascular cognitive impairment groups was significantly greater than the sham operation group （P 〈 0.01）. Learning, memory, and behavior disorders were observed in the vascular cognitive impairment group. Sevoflurane treatment significantly improved these observed disorders. CONCLUSION： Sevoflurane improved cognitive impairment due to permanent bilateral occlusion of both common carotid arteries. Improved function was associated with increased CREB, pCREB, and Livin expression in the cortex and hippocampus.
基金a grant from National Natural Sciences Foundation of China (No. 30872542).
文摘The regulation of hypoxic response elements on the expression of vascular endothelial growth factor （VEGF） gene transfected to primary cultured rat skeletal myoblasts under hypoxic environment was investigated. pEGFP-C3-9HRE-CMV-VEGF vector was constructed with molecular biology technique and transfected to primary cultured rat skeletal myoblasts by lipofectamine in vitro. Gene expression of transfected myoblasts was detected by RT-PCR, Western blot and fluorescence microscope under different oxygen concentrations and different hypoxia time. The results showed that in hypoxia group, the VEGF gene bands were seen and with the decrease of oxygen concentrations and prolongation of hypoxia time, the expression of VEGF mRNA was obviously increased. Under hypoxic environment, the expression of VEGF protein in the transfected myoblasts was significantly increased. EGFP was expressed only under hypoxic environment but not under normoxic environment. It was concluded that hypoxia promoter could be constructed with HRE and regulate the expression of VEGF gene under hypoxic and normoxic environment, which could enhance the re- liability of gene therapy.
文摘Objective:Gastric cancer(GC)is a globally common cancer characterized by high incidence and mortality worldwide.Advances in the molecular understanding of GC provide promising targets for GC diagnosis and therapy.Long non-coding RNAs(lncRNAs)and their downstream regulators are regarded to be implicated in the progression of multiple types of malignancies.Studies have shown that the lncRNA small nucleolar RNA host gene 4(SNHG4)serves as a tumor promoter in various malignancies,while its function in GC has yet to be characterized.Therefore,our study aimed to explore the role and underlying mechanism of SNHG4 in GC.Methods:We used qRT-PCR to analyze SNHG4 expression in GC tissues and cells.Kaplan-Meier analysis was used to assess the correlation between SNHG4 expression and the survival rate of GC patients.Cellular function experiments such as CCK-8,BrdU,colony formation,flow cytometry analysis,and transwell were performed to explore the effects of SNHG4 on GC cell proliferation,apoptosis,cell cycle,migration,and invasion.We also established xenograft mouse models to explore the effect of SNHG4 on GC tumor growth.Mechanically,dual luciferase reporter assay was used to verify the interaction between SNHG4 and miR-409-3p and between miR-409-3p and cAMP responsive element binding protein 1(CREB1).Results:The results indicated that SNHG4 was overexpressed in GC tissues and cell lines,and was linked with poor survival rate of GC patients.SNHG4 promoted GC cell proliferation,migration,and invasion while inhibiting cell apoptosis and cell cycle arrest in vitro.The in vivo experiment indicated that SNHG4 facilitated GC tumor growth.Furthermore,SNHG4 was demonstrated to bind to miR-409-3p.Moreover,CREB1 was directly targeted by miR-409-3p.Rescue assays demonstrated that miR-409-3p deficiency reversed the suppressive impact of SNHG4 knockdown on GC cell malignancy.Additionally,miR-409-3p was also revealed to inhibit GC cell proliferation,migration,and invasion by targeting CREB1.Conclusion:In conclusion,we verified that the SNHG4 promoted GC growth and metastasis by binding to miR-409-3p to upregulate CREB1,which may deepen the understanding of the underlying mechanism in GC development.
文摘The copper-regulated gene expression system has been developed to control spacial and temporal expression of transgene in plant. It comprises two parts: (1) ace I gene encoding copper-responsive transcription factor under the control of a constitutive or organ-specific promoter, and (2) a gene of interest under the control of a chimeric promoter consisting of the CaMV 35S (-90 to +8) promoter linked to the metal responsive element (MRE) carrying activating copper-metallothionein expression (ACE1)-binding sites. Here, the effectiveness of two different ACE1-binding cis -elements which derive from 5'-regulatory region of yeast metallothionein gene was investigated in transgenic tobacco (Nicotiana tabacum L. cv. W38). The results revealed that the MRE (-210 to -126) could increase the system inducibility by 50% - 100% compared with the previously reported MRE (-148 to -105). It is potential to use the copper-inducible system to control valuable gene traits in plant biotechnology.
基金supported by National Natural Science Fundation of China (No.30870835,30821002,and 30900444)National Basic Research Program of China (No. 2007CB512303,2007CB512502,and 2006CB500807)Postdoctoral Fundation of China (No.20080440578)
文摘Objective To explore the role of the extracellular signal-regulated kinase （ERK）/cAMP response element binding protein （CREB） pathway in the induction of long-term potentiation （LTP） in the anterior cingulate cortex （ACC） that may be implicated in pain-related negative emotion. Methods LTP of field potential was recorded in ACC slice and the expressions of phospho-ERK （pERK） and phospho-CREB （pCREB） were examined using immunohistochemistry method. Results LTP could be induced stably in ACC slice by high frequency stimulation （2-train, 100 Hz, 1 s）, while APv （an antagonist of NMDA receptor） could block the induction of LTP in the ACC, indicating that LTP in this experiment was NMDA receptor-dependent. Bath application of PD98059 （50 μmol/L）, a selective MEK inhibitor, at 30 min before tetanic stimulation could completely block the induction of LTP. Moreover, the protein level of pERK in the ACC was transiently increased after LTP induction, starting at 5 rain and returning to basal at 1 h after tetanic stimulation. The protein level of pCREB was also increased after LTP induction. The up-regulation in pERK and pCREB expressions could be blocked by pretreatment of PD98059. Double immunostaining showed that after LTP induction, most pERK was co-localized with pCREB. Conclusion NMDA receptor and ERK-CREB pathway are necessary for the induction of LTP in rat ACC and may play important roles in pain emotion.
基金Supported by Research and Development Department,Ealing Hospital NHS Trust,Uxbridge Road,Southall,London,UB13HW,United Kingdom
文摘AIM:To study the role of hepcidin in hereditary hyperferritinemia cataract syndrome(HHCS). METHODS:Six patients from two families with HHCS, confirmed by genetic analysis showing A to G mutation at position+40 in the L-ferritin gene,were recruited to undergo serum hepcidin and prohepcidin measurements using radioimmunoassay and enzyme linked immunoassay,respectively,and measurements were compared with levels in serum from 25 healthy volunteers(14 females),mean age 36±11.9 years.RESULTS:The serum hepcidin and prohepcidin levels in patients with HHCS were 19.1±18.6 and 187± 120.9 ng/mL,respectively.Serum ferritin was 1716.3± 376μg/L.Liver biopsy in one patient did not show any evidence of iron overload.Serum hepcidin and prohepcidin values in healthy controls(HCs)were 15.30±15.71 and 236.88±83.68 ng/mL,respectively,while serum ferritin was 110±128.08μg/L.There was no statistical difference in serum hepcidin level between the two cohorts(19.1±18.6 ng/mL vs 15.30±15.71 ng/mL,P= 0.612)using two-tailed t-test. CONCLUSION:Serum hepcidin levels in HHCS patients is similar to that in HCs.Our study suggests that circulating ferritin is not a factor influencing hepcidin synthesis and does not have a role in the iron-sensing mechanism in hepatocytes.
基金supported by the National Natural Science Foundation of China (GABA receptor mechanism ofpropofol to promote neural regeneration), No. 30571791
文摘We intraperitoneally injected 10 and 50 mg/kg of propofol for 7 consecutive days to treat a rat model of chronic cerebral ischemia. A low-dose of propofol promoted the expression of brain-derived neurotrophic factor, tyrosine kinase receptor B, phosphorylated cAMP response element binding protein, and cAMP in the hippocampus of aged rats with chronic cerebral ischemia, but a high-dose of propofol inhibited their expression. Results indicated that the protective effect of propofol against cerebral ischemia in aged rats is related to changes in the expression of brain-derived neurotrophic factor and tyrosine kinase receptor B in the hippocampus, and that the cAMP-cAMP responsive element binding protein pathway is involved in the regulatory effect of propofol on brain-derived neurotrophic factor expression.
文摘Objective:To investigate the regulatory role of cyclic adenosine monophosphate responsive element binding protein(CREB)/brain-derived neurotrophic factor(BDNF)signaling pathway in acute sleep deprivation(SD)-induced anxiety-like behavior mice(SD group)to study the mechanism of anxiety-like behavior better.Methods:The SD chamber was used to deprive the mice of sleep,and the anxiety-like behavior of the mice was verified using an open field test(OFT),elevated plus maze(EPM),forced swim test(FST),and tail suspension test(TST).Finally,proteins were detected by Western blotting.Result:OFT showed that the active distance and the time of stay in the central area were significantly reduced(P<0.05).EPM showed that the time and number of open arms in the SD group were significantly lower than in the control group(P<0.05).The FST showed that the forced swimming immobility time of the SD group was significantly lower than that of the control(P<0.05).Moreover,the TST showed that the immobility time of the tail suspension experiment in the SD group was significantly higher than that in the control group(P<0.05).Conclusion:Acute SD can regulate anxiety-like behavior in mice through the CREB/BDNF signaling pathway.
基金supported by grants of funds from the Brazilian government(EMBRAPA,CNPq,CAPES and FAPDF).
文摘Drought is a major environmental factor limiting cotton (Gossypium hirsutum L.) productivity worldwide and projected climate changes could increase their negative effects in the future. Thus, targeting the molecular mechanisms correlated with drought tolerance without reducing productivity is a challenge for plant breeding. In this way, we evaluated the effects of water deficit progress on AtDREB2A-CA transgenic cotton plant responses, driven by the stress-inducible rd29 promoter. Besides shoot and root morphometric traits, gas exchange and osmotic adjustment analyses were also included. Here, we present how altered root traits shown by transgenic plants impacted on physiological acclimation responses when submitted to severe water stress. The integration of AtDREB2A-CA into the cotton genome increased total root volume, surface area and total root length, without negatively affecting shoot morphometric growth parameters and nor phenotypic evaluated traits. Additionally, when compared to wild-type plants, transgenic plants (17-T0 plants and its progeny) highlighted a gradual pattern of phenotypic plasticity tosome photosynthetic parameters such as photosynthetic rate and stomatal conductance with water deficit progress. Transgene also promoted greater shoot development and root robustness (greater and deeper root mass) allowing roots to grow into deeper soil layers. The same morpho-physiological trend was observed in the subsequent generation (17.6-T2). Our results suggest that the altered root traits shown by transgenic plants are the major contributors to higher tolerance response, allowing the AtDRE2A-CA-cotton plants to maintain elevated stomatal conductance and assimilate rates and, consequently, reducing their metabolic costs involved in the antioxidant responses activation. These results also suggest that these morpho-physiological changes increased the number of reproductive structures retained per plant (26% higher) when compared with its non-transgenic counterpart. This is the first report of cotton plants overexpressing the AtDRE2A-CA transcription factor, demonstrating a morpho-physiological and yield advantages under drought stress, without displaying any yield penalty under irrigated conditions. The mechanisms by which the root traits influenced the acclimation of the transgenic plants to severe water deficit conditions are also discussed. These data present an opportunity to use this strategy in cotton breeding programs in order to improve drought adaptation toward better rooting features.
