Persulfidation maintains cytosolic G6PDs activity through changing tetrameric structure and competing cysteine sulfur oxidation under salt stress in Arabidopsis and tomato.

Glucose-6-phosphate dehydrogenases (G6PDs) are essential regulators of cellular redox. Hydrogen sulfide (H2 S) is a small gasotransmitter that improves plant adaptation to stress; however, its role in regulating G6PD oligomerization to resist oxidative stress remains unknown in plants. Persulfidation of cytosolic G6PDs was analyzed by mass spectrometry (MS). The structural change model of AtG6PD6 homooligomer was built by chemical cross-linking coupled with mass spectrometry (CXMS). We isolated AtG6PD6C159A and SlG6PDCC155A transgenic lines to confirm the in vivo function of persulfidated sites with the g6pd5,6 background. Persulfidation occurs at Arabidopsis G6PD6 Cystine (Cys)159 and tomato G6PDC Cys155, leading to alterations of spatial distance between lysine (K)491-K475 from 42.0 Å to 10.3 Å within the G6PD tetramer. The structural alteration occurs in the structural NADP+ binding domain, which governs the stability of G6PD homooligomer. Persulfidation enhances G6PD oligomerization, thereby increasing substrate affinity. Under high salt stress, cytosolic G6PDs activity was inhibited due to oxidative modifications. Persulfidation protects these specific sites and prevents oxidative damage. In summary, H2 S-mediated persulfidation promotes cytosolic G6PD activity by altering homotetrameric structure. The cytosolic G6PD adaptive regulation with two kinds of protein modifications at the atomic and molecular levels is critical for the cellular stress response.

Hydrogen sulfide improves salt tolerance through persulfidation of PMA1 in Arabidopsis.

KEY MESSAGE: A new interaction was found between PMA1 and GRF4. H2S promotes the interaction through persulfidated Cys446 of PMA1. H2S activates PMA1 to maintain K+/Na+ homeostasis through persulfidation under salt stress. Plasma membrane H+-ATPase (PMA) is a transmembrane transporter responsible for pumping protons, and its contribution to salt resistance is indispensable in plants. Hydrogen sulfide (H2S), a small signaling gas molecule, plays the important roles in facilitating adaptation of plants to salt stress. However, how H2S regulates PMA activity remains largely unclear. Here, we show a possible original mechanism for H2S to regulate PMA activity. PMA1, a predominant member in the PMA family of Arabidopsis, has a non-conservative persulfidated cysteine (Cys) residue (Cys446), which is exposed on the surface of PMA1 and located in cation transporter/ATPase domain. A new interaction of PMA1 and GENERAL REGULATORY FACTOR 4 (GRF4, belongs to the 14-3-3 protein family) was found by chemical crosslinking coupled with mass spectrometry (CXMS) in vivo. H2S-mediated persulfidation promoted the binding of PMA1 to GRF4. Further studies showed that H2S enhanced instantaneous H+ efflux and maintained K+/Na+ homeostasis under salt stress. In light of these findings, we suggest that H2S promotes the binding of PMA1 to GRF4 through persulfidation, and then activating PMA, thus improving the salt tolerance of Arabidopsis.

Effect of organic acids and soil particle size on heavy metal removal from bulk soil with washing.

To evaluate the effect of soil particle size on heavy metals removal by washing, two soil samples were collected around a lead-zinc mining area (SM) and lead-zinc smelter (SS). The total content of Cd, Pb and Zn in SM and SS were determined. And the effect of soil particle size on Cd removal by low molecular organic acids was studied. The results showed that Cd was the main pollutant and the total content of Cd in SS can reach to 24.8 mg Kg-1. 68.4% of the total Cd in SM existed in the form of residual state, while 54.7% of the total Cd in SS was in weak acid extractable state. About 50.0% of the Cd distributed in < 2 µm soil size fraction. The washing results indicated that citric acid was a highly efficient eluent among the five low molecular weight organic acids (citric acid, malic acid, tartaric acid, oxalic acid and acetic acid). After washing, 40% and 69.6% of the total Cd in SS and SM can be removed by citric acid, respectively. While only 18.7-40.2% and 32.6-68.7% of Cd was removed from different size fractions of SM and SS, respectively. The species of Cd in soil size fractions affected the removal effect of citric acid. The citric acid can easily remove the weak acid extractable and reducible form of Cd in soil. After eluted by citric acid, the bioavailability of Cd in soil decreased markedly, and the highest decreasing rate reached 93%.

Kinesiophobia could affect shoulder function after repair of rotator cuff tears.

PURPOSE: Kinesiophobia (fear of movement) is a major limiting factor in the return to pre-injury sport level after surgery of rotator cuff tears. The study aims to gain insights into how kinesiophobia affects shoulder pain and function after the repair of full-thickness rotator cuff tears. METHODS: A prospective study was conducted to evaluate patients who underwent rotator cuff repair between January 2019 and December 2019 in our institution. The patients were divided into a trial group with a high kinesiophobia (Tampa Scale for Kinesiophobia [TSK], TSK > 37) and a control group with a low kinesiophobia (TSK ≤ 37). The indicators of interest included the Constant-Murley scores, numerical rating scale (NRS), visual analogue scale (VAS), Oxford Shoulder Score (OSS), and the American shoulder and elbow score (ASES), shoulder function and strength, and range of motion (ROM) at 3 days, 6 weeks, and 12 months after repair of full-thickness rotator cuff tears. RESULTS: In total, 49 patients who underwent repair of full-thickness rotator cuff tears were enrolled, which was divided into a trial group involving 26 patients (mean TSK 52.54) and a control group involving 23 patients (mean TSK 33.43). There were no statistically significant differences in basic information such as age, gender, and length of stay in the two groups. The preoperative and early postoperative functional scores and the Tampa Scale for Kinesiophobia were statistically significant differences between the two groups. However, long-term postoperative follow-up showed no statistically significant difference in ASES, and Constant-Murley scores, OSS, and VAS scores between the two groups as the kinesiophobia changed from positive to negative. CONCLUSION: Degree of kinesiophobia reduced during post-operative rehabilitation of rotator cuff repair patients, but high kinesiophobia is still present in a large portion of the patients after rotator cuff repair. Patients after rotator cuff repair will benefit from early recognition and prevention of kinesiophobia.

A modified single-endobutton technique combined with nice knot for treatment of Rockwood type III or V acromioclavicular joint dislocation.

PURPOSE: Double-endobutton technique, as a widely accepted strategy for the treatment of acromioclavicular joint dislocation, is undergoing constant improvement. This study aims to assess the clinical effect of a modified single-endobutton combined with the nice knot in the fixation of Rockwood type III or V acromioclavicular joint dislocation. METHODS: From January 2016 to June 2019, 16 adult patients (13 males and 3 females) with Rockwood type III or V acromioclavicular joint dislocation were treated with a modified single-endobutton technique combined with the nice knot in our department. The age ranged from 18 to 64 years old with an average of 32.8 years old. Operative time, intraoperative blood loss, post-operative clinical outcomes and radiographic results were recorded and analyzed. Preoperative and last follow-up scores in the Constant-Murley Scale, Neer score, Rating Scale of the American Shoulder and Elbow Surgeons and VAS scale and complications such as infection, re-dislocation, implant loosening, medical origin fracture and hardware pain were recorded and evaluated. RESULTS: Sixteen patients were followed up for 6 to 18 months with an average of 10.3 months. The operative time was 50-90 min with an average of (62.5 ± 3.10) min. The intraoperative blood loss was 30-100 ml, with an average of (55.0 ± 4.28) ml. The complications, such as wound infection, internal fixation failure and fractures, were not found in these cases. According to Karlsson criteria, there were excellent in 14 cases, good in 2 cases at the final follow-up. The mean VAS score of the patients was 5.88 ± 0.26 preoperatively, compared with 0.19 ± 0.14 at the final follow-up evaluation. The difference was statistically significant (P < 0.05). The mean Constant score was 45.5 ± 2.0 preoperatively, compared to 94.0 ± 0.73 at the final follow-up evaluation. The difference was statistically significant (P < 0.05). Patients had statistically significant preoperative and postoperative AC (acromioclavicular distance) and CC (coracoclavicular distance) distances (P < 0.05); 6 months postoperatively the AC(P = 0.412) and CC(P = 0.324) distances were not statistically significant compared to the healthy side. CONCLUSION: Nice knot provides a reliable fixation for the single-endobutton technique in the treatment of acromioclavicular dislocations. The modified single-endobutton technique combined with the nice knot can achieve good clinical outcomes in the treatment of Rockwood type III or V acromioclavicular joint dislocation.

Intraoperative Nice knots assistance for reduction in displaced comminuted clavicle fractures.

PURPOSE: The Nice knots have been widely used in orthopedic surgeries to fix torn soft tissue and fracture in recent years. The study aims to investigate the clinical efficacy and prognosis of intraoperative and postoperative Nice Knots-assisted reduction in the treatment of displaced comminuted clavicle fracture. METHODS: From Jan 2014 to Dec 2019, 75 patients diagnosed with unilateral closed displaced comminuted clavicle fracture were treated with open reduction and internal fixation (ORIF) in this study. Nice knot group (the NK group) included 38 patients and the other 37 patients were in the traditional group (the TK group). The time of operation and the amount of bleeding during operation were recorded. Post-operative clinical outcomes and radiographic results were recorded and compared between these two groups. The Visual Analogue Scale (VAS), Neer score, Rating Scale of the American Shoulder and Elbow Surgeons, Constant-Murley score and complications such as infection, nonunion, implant loosening, fragment displacement and hardware pain were observed in the two groups. RESULTS: In the comparison between the two groups, there was no significant difference in age, sex, the cause of displaced clavicle fracture, and other basic information between the two groups. The operation time, intraoperative fluoroscopy time, and intraoperative blood loss were significantly reduced in the NK group (P < 0.01). There were 2 cases of plate fracture in the TK group. The follow-up results showed that there was no significant difference in VAS, Neer score, ASES, and Constant-Murley scores between the two groups. CONCLUSION: The use of Nice knot, in comminuted and displaced clavicle fractures can reduce intraoperative blood loss, shorten operation time, facilitate intraoperative reduction, and achieve satisfactory postoperative clinical results. This study demonstrates that Nice knot is a simple, safe, practical and effective auxiliary reduction method.

Exogenous salicylic acid regulates cell wall polysaccharides synthesis and pectin methylation to reduce Cd accumulation of tomato.

Cadmium (Cd) is harmful to plant growth and can be easily transferred from soil to plants. Plant cell wall plays important role in preventing Cd from entering cells. Salicylic acid (SA) mediated defense response increases plant resistance to heavy metals. In this study, all tomato seedlings were pre-treated with 100 µM SA for 3 d, then seedlings were used to analyze the role of SA in regulating plant cell wall resistance to Cd stress. The results showed that exogenous SA significantly reduced Cd accumulation in tomato plants and changed Cd distribution. By analyzing the cell wall composition, it was found cellulose, hemicellulose, pectin, and lignin were induced by SA. Interestingly, the content of Cd in pectin decreased by SA pretreatment, however it was increased in cellulose. Gene expression analysis showed SA up-regulated the expression level of lignin and cellulose synthase genes, but down-regulated the expression of pectin methylesterase related genes. In addition, SA down-regulated the activity of pectin methylesterase. These results indicated that SA pretreatment up-regulated cell wall polysaccharide synthesis and related gene expression to thicken the cell wall and block Cd from passing through. Furthermore, SA decreased pectin methylesterase activity and content to reduce cell wall Cd accumulation and change the Cd partition ratio.

Rhizosphere iron and manganese-oxidizing bacteria stimulate root iron plaque formation and regulate Cd uptake of rice plants (Oryza sativa L.).

Iron plaque is the amorphous and/or crystalline layer of Fe and Mn (hydr)oxides formed on the root surface of wetland plants. It could adsorb and co-precipitate metal(loid)s at the rhizosphere, thus modulating the uptake and accumulation of metal elements in plants. In this study, the Fe(II)/Mn(II)-oxidizing bacteria Burkholderia sp. D416 (D416) and Pseudomonas sp. YGL (YGL) were isolated from Cd-contaminated rice field, both hydroponic experiment and pot experiment were performed to assess the impact of bacterial inoculation on iron plaque formation, elemental content of the plaque, plant dry mass, antioxidant enzyme activity and Cd content in rice plants. The results revealed that inoculation with D416, YGL, and D416+YGL stimulated iron plaque formation on the root surface of the hydroponic rice. The content of C, N, O, Na, Mg, Al, Si, P, S, Cl, K, Fe and Ca in the root plaque were affected by the bacterial inoculation and varied among different plant growth stages. The pot experiment indicated that inoculation with D416 increased the root dry biomass by 58.89%, and the combined inoculation of D416 and YGL increased the dry biomass of root, shoot and grain by 16.89%, 21.66% and 23.26%, respectively. Importantly, YGL inoculation decreased the Cd translocation from root to shoot and from glume to brown rice grain by 50.00% and 50.27%, respectively, and the Cd content in shoot and brown rice grain were decreased by 20.00% and 34.48%, respectively. Taken together, the elemental content of the iron plaque and Cd content in rice plants varied among different plant growth stages and when plants were inoculated with different bacterial strains. YGL dramatically reduced the Cd content in brown rice grain, thus it could potentially be used to reduce Cd content in rice crop grown in Cd-contaminated soils.

Hydrogen sulfide promotes hypocotyl elongation via increasing cellulose content and changing the arrangement of cellulose fibrils in alfalfa.

Hydrogen sulfide (H2S) is known to have positive physiological functions in plant growth, but limited data are available on its influence on cell walls. Here, we demonstrate a novel mechanism by which H2S regulates the biosynthesis and deposition of cell wall cellulose in alfalfa (Medicago sativa). Treatment with NaHS was found to increase the length of epidermal cells in the hypocotyl, and transcriptome analysis indicated that it caused the differential expression of numerous of cell wall-related genes. These differentially expressed genes were directly associated with the biosynthesis of cellulose and hemicellulose, and with the degradation of pectin. Analysis of cell wall composition showed that NaHS treatment increased the contents of cellulose and hemicellulose, but decreased the pectin content. Atomic force microscopy revealed that treatment with NaHS decreased the diameter of cellulose fibrils, altered the arrangement of the fibrillar bundles, and increased the spacing between the bundles. The dynamics of cellulose synthase complexes (CSCs) were closely related to cellulose synthesis, and NaHS increased the rate of mobility of the particles. Overall, our results suggest that the H2S signal enhances the plasticity of the cell wall by regulating the deposition of cellulose fibrils and by decreasing the pectin content. The resulting increases in cellulose and hemicellulose contents lead to cell wall expansion and cell elongation.

Salinity relief aniline induced oxidative stress in Suaeda salsa: Activities of antioxidative enzyme and EPR measurements.

Wastewater from printing and dyeing processes often contains aniline and high salinity, which are hazardous to aquatic species. Glycophytic plants cannot survive under high-salinity conditions, whereas halophytes grow well in such an environment. In this study, we investigated the influence of NaCl on the antioxidant level in Suaeda salsa affected by aniline stress. The seedlings showed various growth toxicity effects under different concentrations of aniline. The results showed that the effect of the aniline was more severe for the root growth compared to that for the shoot growth. Aniline exposure significantly increased the total free radicals and ·OH radicals in the plants. Suaeda salsa exposure to aniline caused oxidative stress by altering the superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) activity, which resulted in the overproduction of H2O2 and the inducement of lipid peroxidation. Analysis revealed that the malondialdehyde (MDA) content was enhanced after aniline exposure and that the chlorophyll content was significantly decreased. The results showed that aniline induced the production of free radicals and reactive oxygen species (ROS), and changed the antioxidant defense system. This ultimately resulted in oxidative damage in S. salsa; however, it was found that moderate salinity could mitigate the effects. In conclusion, salinity may alleviate the growth inhibition caused by aniline by regulating the antioxidant capacity of S. salsa.

An Acquisition Method of Agricultural Equipment Roll Angle Based on Multi-Source Information Fusion.

Accurately obtaining roll angles is one of the key technologies to improve the positioning accuracy and operation quality of agricultural equipment. Given the demand for the acquisition of agricultural equipment roll angles, a roll angle monitoring model based on Kalman filtering and multi-source information fusion was established by using the MTi-300 AHRS inertial sensor (INS) and XW-GI 5630 BeiDou Navigation Satellite System (BDS), which were installed on agricultural equipment. Data of the INS and BDS were fused by MATLAB; then, Kalman filter was used to optimize the data, and the state equation and measurement equation of the integrated system were established. Then, an integrated monitoring terminal man-machine interactive interface was designed on MATLAB GUI, and a roll angle monitoring system based on the INS and BDS was designed and applied into field experiments. The mean absolute error of the integrated monitoring system based on multi-source information fusion during field experiments was 0.72°, which was smaller compared with the mean absolute errors of roll angle monitored by the INS and BDS independently (0.78° and 0.75°, respectively). Thus, the roll angle integrated model improves monitoring precision and underlies future research on navigation and independent operation of agricultural equipment.

Feature Point Registration Model of Farmland Surface and Its Application Based on a Monocular Camera.

In this study, an image registration algorithm was applied to calculate the rotation angle of objects when matching images. Some commonly used image feature detection algorithms such as features from accelerated segment test (FAST), speeded up robust features (SURF) and maximally stable extremal regions (MSER) algorithms were chosen as feature extraction components. Comparing the running time and accuracy, the image registration algorithm based on SURF has better performance than the other algorithms. Accurately obtaining the roll angle is one of the key technologies to improve the positioning accuracy and operation quality of agricultural equipment. To acquire the roll angle of agriculture machinery, a roll angle acquisition model based on the image registration algorithm was built. Then, the performance of the model with a monocular camera was tested in the field. The field test showed that the average error of the rolling angle was 0.61°, while the minimum error was 0.08°. The field test indicated that the model could accurately obtain the attitude change trend of agricultural machinery when it was working in irregular farmlands. The model described in this paper could provide a foundation for agricultural equipment navigation and autonomous driving.

Effects of EDTA and plant growth-promoting rhizobacteria on plant growth and heavy metal uptake of hyperaccumulator Sedum alfredii Hance.

Phytoremediation is a cost-effective and environment-friendly strategy for decontaminating heavy-metal-contaminated soil. However, the practical use of phytoremediation is constrained by the low biomass of plants and low bioavailability of heavy metals in soil. A pot experiment was conducted to investigate the effects of the metal chelator ethylenediaminetetraacetic acid (EDTA) and EDTA in combination with plant growth-promoting rhizobacteria (Burkholderia sp. D54 or Burkholderia sp. D416) on the growth and metal uptake of the hyperaccumulator Sedum alfredii Hance. According to the results, EDTA application decreased shoot and root biomass by 50% and 43%, respectively. The soil respiration and Cd, Pb, Zn uptake were depressed, while the photosynthetic rate, glutathione and phytochelatin (PC) contents were increased by EDTA application. Interestingly, Burkholderia sp. D54 and Burkholderia sp. D416 inoculation significantly relieved the inhibitory effects of EDTA on plant growth and soil respiration. Compared with the control, EDTA + D416 treatment increased the Cd concentration in shoots and decreased the Pb concentration in shoots and roots, but did not change the Zn concentration in S. alfredii plants. Furthermore, EDTA, EDTA + D54 and EDTA + D416 application increased the cysteine and PC contents in S. alfredii (p < 0.05); among all tested PCs, the most abundant species was PC2, and compared with the control, the PC2 content was increased by 371.0%, 1158.6% and 815.6%, respectively. These results will provide some insights into the practical use of EDTA and PGPR in the phytoremediation of heavy-metal-contaminated soil by S. alfredii.

Retracted: Downregulation of microRNA-367 promotes osteoblasts growth and proliferation of mice during fracture by activating the PANX3-mediated Wnt/ß-catenin pathway.

A majority of people suffering from bone fractures fail to heal and develop a nonunion, which is a challenging orthopedic complication requiring complex and expensive treatment. Previous data showed the inhibition of some microRNAs (miRNAs or miRs) can enhance fracture healing. The objective of the present study is to explore effects of miR-367 on the osteoblasts growth and proliferation of mouse during fracture via the Wnt/ß-catenin pathway by targeting PANX3. Primarily, the femur fracture model was successfully established in 66 (C57BL/6) 6-week-old male mice. To verify whether miR-367 target PANX3, we used the target prediction program and performed luciferase activity determination. Subsequently, to figure out the underlying regulatory roles of miR-367 in fracture, osteoblasts were elucidated by treatment with miR-367 mimic, miR-367 inhibitor, or siRNA against PANX3 to determine the expression of miR-367, siPANX3, ß-catenin, and Wnt5b as well as cell proliferation and apoptosis. The results demonstrated that PANX3 was verified as a target gene of miR-367. MiR-367 was found to highly expressed but PANX3, ß-catenin, and Wnt5b were observed poorly expressed in fracture mice. downregulated miR-367 increased the mRNA and protein expression of PANX3, ß-catenin, and Wnt5b, increased cell growth, proliferation, and migration, while decreased cell apoptosis in osteoblasts. Altogether, our study demonstrates that the downregulation of miR-367 may promote osteoblasts growth and proliferation in fracture through the activation of the PANX3-dependent Wnt/ß-catenin pathway.

Hydrogen Sulfide Disturbs Actin Polymerization via S-Sulfhydration Resulting in Stunted Root Hair Growth.

Hydrogen sulfide (H2S) is an important signaling molecule in plants. Our previous report suggested that H2S signaling affects the actin cytoskeleton and root hair growth. However, the underlying mechanisms of its effects are not understood. S-Sulfhydration of proteins is regulated directly by H2S, which converts the thiol groups of cysteine (Cys) residues to persulfides and alters protein function. In this work, we studied the effects of S-sulfhydration on actin dynamics in Arabidopsis (Arabidopsis thaliana). We generated transgenic plants overexpressing the H2S biosynthesis-related genes l-CYSTEINE DESULFHYDRASE (LCD) and d-CYSTEINE DESULFHYDRASE in the O-acetylserine(thiol)lyase isoform a1 (oasa1) mutant and Columbia-0 backgrounds. The H2S content increased significantly in overexpressing LCD/oasa1 plants. The density of filamentous actin (F-actin) bundles and the F-actin/globular actin ratio decreased in overexpressing LCD/oasa1 plants. S-Sulfhydration also was enhanced in overexpressing LCD/oasa1 plants. An analysis of actin dynamics suggested that S-sulfhydration inhibited actin polymerization. We also found that ACTIN2 (ACT2) was S-sulfhydrated at Cys-287. Cys-287 is adjacent to the D-loop, which acts as a central region for hydrophobic and electrostatic interactions and stabilizes F-actin filaments. Overaccumulation of H2S caused the depolymerization of F-actin bundles and inhibited root hair growth. Introduction of ACT2 carrying a Cys-287-to-Ser mutation into an act2-1 mutant partially suppressed H2S-dependent inhibition of root hair growth. We conclude that H2S regulates actin dynamics and affects root hair growth.

A Novel Method for Soil Organic Matter Determination by Using an Artificial Olfactory System.

Soil organic matter (SOM) is a major indicator of soil fertility and nutrients. In this study, a soil organic matter measuring method based on an artificial olfactory system (AOS) was designed. An array composed of 10 identical gas sensors controlled at different temperatures was used to collect soil gases. From the response curve of each sensor, four features were extracted (maximum value, mean differential coefficient value, response area value, and the transient value at the 20th second). Then, soil organic matter regression prediction models were built based on back-propagation neural network (BPNN), support vector regression (SVR), and partial least squares regression (PLSR). The prediction performance of each model was evaluated using the coefficient of determination (R2), root-mean-square error (RMSE), and the ratio of performance to deviation (RPD). It was found that the R2 values between prediction (from BPNN, SVR, and PLSR) and observation were 0.880, 0.895, and 0.808. RMSEs were 14.916, 14.094, and 18.890, and RPDs were 2.837, 3.003, and 2.240, respectively. SVR had higher prediction ability than BPNN and PLSR and can be used to accurately predict organic matter contents. Thus, our findings offer brand new methods for predicting SOM.

Effects of salicylic acid, Epi-brassinolide and calcium on stress alleviation and Cd accumulation in tomato plants.

Salicylic acid (SA), Epi-brassinolide (EBL) and calcium (Ca) play crucial roles in plant development and mediate plant response to biotic and abiotic stress. This study was aimed to investigate the possible mediatory role of SA, EBL, Ca or their combination in protecting tomato plants from cadmium (Cd) toxicity. According to the results, Cd stress resulted in a significant reduction of plant dry mass, photosynthetic pigment content as well as photosynthetic rate. Exogenous application of SA decreased the malondialdehyde (MDA) level by 39.27% and increased catalase (CAT) activity by 81.17%. SA and EBL treatment significantly increased chlorophyll a (Chl a), chlorophyll b (Chl b) content, photosynthetic rate (Pn) as well as water use efficiency (WUE). SA+EBL (1:1)/Ca+SA+EBL (1:1:1) treatment obviously alleviated Cd-induced growth inhibition, the dry mass of different tomato organs were significantly increased (p < 0.05). Especially in Ca+SA+EBL treated plants, the dry mass of roots, stems and leaves increased by 141.18%, 128.57% and 118.52%, respectively. Besides, SA+EBL and Ca+SA+EBL treatments reduced the MDA level, but increased photosynthetic pigment concentration and photosynthetic efficiency. CAT activity was increased by 62.92% in Ca+SA+EBL treated plants, the WUE was increased by 557.76% in SA+EBL pretreated plants. Moreover, exogenous application of SA, SA+EBL and Ca+SA+EBL significantly decreased Cd accumulation in tomato organs (p < 0.05) compared with Cd-stressed plants. Taken together, our results indicated that exogenous application of SA, EBL and Ca individually or in combination could alleviate Cd toxicity in tomato plants, although the extent varies.

Effects of salicylic acid, Fe(II) and plant growth-promoting bacteria on Cd accumulation and toxicity alleviation of Cd tolerant and sensitive tomato genotypes.

In this study, we investigated the ameliorative effects of salicylic acid (SA), metal ion (Fe(II)), and plant growth-promoting bacteria Burkholderia sp. D54 (B) on two tomato genotypes with different Cd tolerances under Cd stress, viz. Liger (Cd tolerant) and Tabd (Cd sensitive). The plant biomass, Cd accumulation, antioxidative response, pigment content and photosynthetic performance were determined. According to the results, exogenous application of SA, Fe(II) and Burkholderia sp. D54 or their complex effectively reduced Cd accumulation and increased biomass of root, stem and leaves in both Cd sensitive and Cd tolerant genotypes. Among all treatments, SA+Fe+B exerted the best performance. Burkholderia sp. D54 effectively alleviated Cd-induced oxidative toxicity in both tomato genotypes, while SA ameliorated oxidative stress in Cd sensitive genotype. Photosynthetic pigment content and photosynthetic rate of Cd tolerant genotype was increased by all treatments, but only SA and Burkholderia sp. D54 treatment increased pigment contents and photosynthetic performance in Cd sensitive genotypes. All treatments significantly decreased Cd accumulation in both tomato genotypes. The effect of Cd reduction was Fe+SA+B>SA>Fe>B. Taken together, our results indicated that exogenous application of SA, Fe(II) and Burkholderia sp. D54 could alleviate the Cd toxicity in both Cd sensitive and Cd tolerant genotypes, although the extent varies.

Anisotropic Cell Expansion Is Affected through the Bidirectional Mobility of Cellulose Synthase Complexes and Phosphorylation at Two Critical Residues on CESA3.

Here we report that phosphorylation status of S211 and T212 of the CESA3 component of Arabidopsis (Arabidopsis thaliana) cellulose synthase impacts the regulation of anisotropic cell expansion as well as cellulose synthesis and deposition and microtubule-dependent bidirectional mobility of CESA complexes. Mutation of S211 to Ala caused a significant decrease in the length of etiolated hypocotyls and primary roots, while root hairs were not significantly affected. By contrast, the S211E mutation stunted the growth of root hairs, but primary roots were not significantly affected. Similarly, T212E caused a decrease in the length of root hairs but not root length. However, T212E stunted the growth of etiolated hypocotyls. Live-cell imaging of fluorescently labeled CESA showed that the rate of movement of CESA particles was directionally asymmetric in etiolated hypocotyls of S211A and T212E mutants, while similar bidirectional velocities were observed with the wild-type control and S211E and T212A mutant lines. Analysis of cell wall composition and the innermost layer of cell wall suggests a role for phosphorylation of CESA3 S211 and T212 in cellulose aggregation into fibrillar bundles. These results suggest that microtubule-guided bidirectional mobility of CESA complexes is fine-tuned by phosphorylation of CESA3 S211 and T212, which may, in turn, modulate cellulose synthesis and organization, resulting in or contributing to the observed defects of anisotropic cell expansion.

Prognostic value of MMP-2 for patients with ovarian epithelial carcinoma: a systematic review and meta-analysis.

BACKGROUND: The reported roles of matrix metalloproteinase 2 (MMP-2) on the prognosis of patients with epithelial ovarian cancers (EOCs) are inconsistent. OBJECTIVE: This meta-analysis was performed to evaluate the prognostic significance of MMP-2 for patients with EOCs by analyzing 11 studies. METHODS: We systematically searched articles in the Cochrane Library, Pubmed, Embase, China National Knowledge Infrastructure (CNKI), Wanfang Database, and Chinese Biological Medical (CBM) Database, updated to February 1st 2015, with the following search terms: ovarian neoplasm OR ovarian tumor OR ovarian carcinoma OR ovarian malignance OR ovarian cancer AND matrix metalloproteinase-2 OR MMP-2. RESULTS: A total of 11 studies involving 1058 patients with EOCs were in accordance with the inclusion criteria. The pooled HR was 1.09 (95% CI 0.32-1.86, p = 0.006) in patients with overexpression of stromal MMP-2 with significant heterogeneity (I 2 = 53.1%, p = 0.074) between studies. For patients with MMP-2 overexpression in tumor cells, the pooled HR was 1.42 (95% CI 1.14-1.70, p = 0.000) with no significant heterogeneity (I 2 = 43.4%, p = 0.078) between studies. Sensitivity analyses were stable. CONCLUSIONS: MMP-2 overexpression in tumor cells rather than stroma was significantly associated with poor prognosis in patient with endothelial ovarian cancer; however, the result remains to be confirmed with additional high-quality studies.