Transcriptomic analysis reveals GA3 is involved in regulating flavonoid metabolism in grape development for facility cultivation.

Gibberellin, as one of the pivotal plant growth regulators, can improve fruit quality by altering fruit size and secondary metabolite content. Flavonoids are the most abundant secondary metabolites in grapes, which influence the color and quality of the fruit. However, the molecular mechanism of whether and how GA3 affects flavonoid metabolism has not been reported, especially for the 'Red globe' grape with delayed cultivation in Hexi corridor. In the present study, the 'Red globe' grape grown in delayed facilities was sprayed with 20, 40, 60, 80 and 100 mg/L GA3 at berries pea size (BPS), veraison (V) and berries ripe (BR), respectively. The results showed that the berry weight, soluble sugar content and secondary metabolite content (the flavonoid content, anthocyanin content and polyphenol content) at BR under 80 mg/L GA3 treatment were remarkably increased compared with other concentration treatments. Therefore, RNA sequencing (RNA-seq) was used to analyze the differentially expressed genes (DEGS) and pathways under 80 mg/L GA3 treatment at three periods. GO analysis showed that DEGs were closely related to transporter activity, cofactor binding, photosynthetic membrane, thylakoid, ribosome biogenesis and other items. The KEGG enrichment analysis found that the DEGs were mainly involved in flavonoid biosynthesis and phenylpropanoid biosynthesis, indicating GA3 exerted an impact on the color and quality of berries through these pathways. In conclusion, GA3 significantly increased the expression of genes related to flavonoid synthesis, enhanced the production of secondary metabolites, and improved fruit quality. In addition, these findings can provide a theoretical basis for GA3 to modulate the accumulation and metabolism of flavonoids in grape fruit.

Transcription factors dealing with Iron-deficiency stress in plants: focus on the bHLH transcription factor family.

Iron (Fe), as an important micronutrient element necessary for plant growth and development, not only participates in multiple physiological and biochemical reactions in cells but also exerts a crucial role in respiration and photosynthetic electron transport. Since Fe is mainly present in the soil in the form of iron hydroxide, Fe deficiency exists universally in plants and has become an important factor triggering crop yield reduction and quality decline. It has been shown that transcription factors (TFs), as an important part of plant signaling pathways, not only coordinate the internal signals of different interaction partners during plant development, but also participate in plant responses to biological and abiotic stresses, such as Fe deficiency stress. Here, the role of bHLH transcription factors in the regulation of Fe homeostasis (mainly Fe uptake) is discussed with emphasis on the functions of MYB, WRKY and other TFs in the maintenance of Fe homeostasis. This review provides a theoretical basis for further studies on the regulation of TFs in Fe deficiency stress response.

Molecular cloning and functional characterization of MhHEC2-like genes in Malus halliana reveals it enhances Fe (iron) deficiency tolerance.

The basic helix-loop-helix (bHLH) family, as one of the largest families of transcription factors (TFs) in plants, plays crucial roles in regulating growth, development, and abiotic stress responses. However, studies on the association of the bHLH genes with apple iron (Fe) deficiency are limited. Here, multiple bHLH genes that responded to Fe deficiency were selected for quantitative real-time PCR in Malus halliana. The results showed that the expression of HEC2-like gene exerted more values compared to other genes under Fe deficiency stress, but the mechanism by which it regulates Fe deficiency stress is unclear. Subsequently, MhHEC2-like gene (ID: 103,455,961) was cloned from M. halliana for functional identification. We found that both transgenic Arabidopsis thaliana and tobacco displayed less chlorosis and more robust growth than wild-type (WT) controls under Fe deficiency stress. At the same time, the overexpressed apple calli grew prominently larger and better under Fe deficiency compared to the wild type. On the other hand, physiological index measurements revealed that overexpressed MhHEC2-like gene enhanced tolerance to Fe deficiency stress in A. thaliana and tobacco by promoting the synthesis of photosynthetic pigments, improving antioxidant enzyme activity, and enhancing Fe reduction, and strengthened tolerance to Fe deficiency stress in apple calli by reducing pH, boosting Fe reduction, and increasing antioxidant enzyme activity. To sum up, the overexpression of MhHEC2-like gene strengthened tolerance to Fe deficiency stress in Arabidopsis thaliana, tobacco, and apple calli.

Genome-wide identification of the CER1 gene family in apple and response of MdCER1-1 to drought stress.

Plant cuticular wax was a major consideration affecting the growth and quality of plants through protecting the plant from drought and other diseases. According to existing studies, CER1, as the core enzyme encoding the synthesis of alkanes, the main component of wax, can directly affect the response of plants to stress. However, there were few studies on the related functions of CER1 in apple. In this study, three MdCER1 genes in Malus domestica were identified and named MdCER1-1, MdCER1-2, and MdCER1-3 according to their distribution on chromosomes. Then, their physicochemical properties, sequence characteristics, and expression patterns were analyzed. MdCER1-1, with the highest expression level among the three members, was screened for cloning and functional verification. Real-time fluorescence quantitative PCR (qRT-PCR) analysis also showed that drought stress could increase the expression level of MdCER1-1. The experiment of water loss showed that overexpression of MdCER1-1 could effectively prevent water loss in apple calli, and the effect was more significant under drought stress. Meanwhile, MdYPB5, MdCER3, and MdKCS1 were significantly up-regulated, which would be bound up with waxy metabolism. Gas chromatography-mass spectrometer assay of wax fraction makes known that overexpression of MdCER1-1 apparently scaled up capacity of alkanes. The enzyme activities (SOD, POD) of overexpressed apple calli increased significantly, while the contents of proline increased compared with wild-type calli. In conclusion, MdCER1-1 can resist drought stress by reducing water loss in apple calli epidermis, increasing alkanes component content, stimulating the expression of waxy related genes (MdYPB5, MdCER3, and MdKCS1), and increasing antioxidant enzyme activity, which also provided a theoretical basis for exploring the role of waxy in other stresses.

Predictors of Deterioration in Sagittal Balance Following Long Fusion Arthrodesis to L5 in Patients with Adult Scoliosis.

BACKGROUND The aim of this study was to identify the predictors of deterioration in sagittal balance in patients with adult scoliosis following long fusion arthrodesis to L5. MATERIAL AND METHODS A retrospective clinical study included 63 patients with adult scoliosis who underwent long fusion arthrodesis to L5, between February 2005 and May 2015. Radiological imaging values included the angle of lumbar lordosis (LL), and the angle of pelvic incidence (PI). The patients were divided into two cohorts, according to the threshold of average loss of sagittal vertical axis (SVA): a cohort with stable sagittal balance (SSB) and a cohort with deteriorated sagittal balance (DSB). Multivariate logistic regression analysis and the receiver operating characteristic (ROC) curve were used to identify the predictors of clinical outcome. RESULTS There were significant differences between the SSB and DSB cohorts in age (p<0.001), preoperative SVA (p<0.001), last follow-up SVA (p<0.001), preoperative LL (p=0.001), last follow-up LL (p<0.001), subsequent L5-S1 disc degeneration (p<0.001) and PI (p=0.028). Patient age >61.5 years (OR=1.251, 95% CI, 1.055-1.484) (P=0.010), preoperative SVA >3.54 cm (OR=1.844, 95% CI, 1.249-2.732) (P=0.002) and preoperative LL <19.0 degrees (OR=0.922, 95% CI, 0.869-0.979) (P=0.008) were identified as predictors of deterioration in sagittal balance. CONCLUSIONS Deterioration in sagittal balance following long fusion arthrodesis to L5 in patients with adult scoliosis was associated with subsequent L5-S1 disc degeneration and loss of LL, age >61.5 years, preoperative SVA >3.54 cm, and preoperative LL <19.0 degrees.

Transcriptome analysis reveals wax and phytohormone metabolism potentially involved in shooting shrivelling of apple branches overwinter.

Shoot shrivelling severely threatens growth and development of deciduous trees in the northern hemisphere, and we observed that there was a significant difference in shoot shrivelling rate between different apple varieties in practice. In this study, we investigated the anatomical and physiological characteristics of branches from different germplasm resources combined with an analysis of the transcriptome. Transcriptomes of samples treated in the initial dormancy, deep dormancy and freeze-thaw periods were generated and characterised. In three different periods, 7233 differentially expressed genes (DEGs) were identified including 3538 upregulated genes and 3695 downregulated genes. DEGs related to plant hormone signal transduction, starch and sucrose metabolism, cutin, suberin and wax biosynthesis were significantly enriched. Physiological characterisation showed that dormancy overwinter can induce the accumulation of soluble sugar and starch, shoot shrivelling rate of 'Fuji' was 2.31times that of the 'Delicious'; and the critical water content of 'Delicious' was significantly higher than 'Fuji'. Phytohormone contents and proportions varied irregularly according to the overwintering phase among two varieties. Wax content, morphology and composition also exhibited difference. In conclusion, branch microstructure, phytohormone and wax metabolism all determined the overwintering performance of trees and phytohormones can regulate wax metabolism to ensure normal overwintering of trees.

Effect of PVC film pretreatment on performance and lamination of wood-plastic composite plywood.

In order to solve the practical problem of heat transfer during the hot pressing process of a novel wood-plastic composite plywood, this paper investigates the perforation treatment of polyvinyl chloride (PVC) plastic films and their plywood composites. The PVC films were pretreated by the physical punching method, and the effects of PVC perforation diameter, hot pressing time and hot pressing temperature on the mechanical properties of the plywood composites were investigated by orthogonal experimental design. The results showed that the optimum hot pressing time was 7 min, the hot pressing temperature was 170 °C, and the PVC perforation diameter was 15 mm for the optimum mechanical properties. The punching pretreatment of PVC films gave rise to a reduction of the hot pressing time by 51 s due to improved heat transfer and heat loss by 5.06%, and allowed an increase in the initial moisture content of the veneer by 2-3%, thereby cutting down the drying cost in the veneer production process, which is conducive to energy conservation and environmental protection.

Potential risk factors for poor outcome after anterior surgery for patients with cervical ossification of the posterior longitudinal ligament.

OBJECTIVE: Our purpose here was to identify risk factors of poor outcome after anterior operation in patients with cervical ossification of the posterior longitudinal ligament (OPLL). METHODS: This study retrospectively reviewed 98 patients who underwent anterior surgery for improving neurological symptoms. The Japanese Orthopedic Association (JOA) recovery rate <50% was defined as poor surgical outcome. We investigated the relationship between various predictors and outcome by logistic regression analysis and receiver operating characteristic curves. To explore the cause of cerebrospinal fluid (CSF) leakage, we used the Mann-Whitney U-test, χ2 test, or independent t-test. RESULTS: Multivariate logistic regression analysis showed that age (odds ratio [OR] =1.1, 95% confidence interval [CI] =1.03-1.18, P=0.005), occupying ratio of OPLL (OR =1.08, 95% CI =1.03-1.12, P=0.001), and residual ratio of OPLL (OR =1.07, 95% CI =1.02-1.13, P=0.008) were independently associated with poor outcome. The cutoffs of the above risk factors were set at 63.5 years, 39.65%, and 25.165%, respectively. Predictors for CSF leakage were occupying ratio of OPLL, the K-line, and shape of the ossified lesion (P<0.001, P=0.019, and P=0.003). CONCLUSION: These findings suggest that advanced age, high occupying ratio of OPLL, and high residual ratio of OPLL were risk factors for postoperative poor outcome in patients with OPLL. In addition, the high occupying ratio of OPLL, the K-line (-), and hill-shape ossification were potential causes of CSF leakage.

Lumbar spondylolisthesis is a risk factor for osteoporotic vertebral fractures: a case-control study.

Objective This study aimed to identify the risk factors for vertebral compression fractures in patients with osteoporosis. Methods A total of 864 patients with osteoporosis were enrolled in a retrospective study from February 2010 to June 2016. Patients with diseases, such as pathological fractures, high-energy direct injury to the thoracic or lumbar vertebrae, and severe spinal deformity, were excluded. The patients were divided into two groups: those with vertebral compression fractures (288) and those with no vertebral compression fractures (576). Information on the patients' age, sex, lumbar bone mineral density (BMD), trauma, body mass index, previous history of vertebral compression fractures, and spondylolisthesis was recorded. Logistic regression analysis and the chi-square test were applied for comparisons. Results Univariate logistic regression analysis and chi-square test results showed no significant differences in age, sex, body mass index, type 2 diabetes, previous history of vertebral fracture, and trivial trauma between the groups. Multivariate analysis showed significant associations between spondylolisthesis and BMD. Logistic regression analysis showed that spondylolisthesis and BMD were risk factors for vertebral compression fractures. Conclusions Lumbar spondylolisthesis is an independent risk factor for vertebral compression fractures in patients with osteoporosis. Therefore, patients with osteoporosis and lumbar spondylolisthesis require more attention.