ARF2-PIF5 interaction controls transcriptional reprogramming in the ABS3-mediated plant senescence pathway.

One of the hallmarks of plant senescence is the global transcriptional reprogramming coordinated by a plethora of transcription factors (TFs). However, mechanisms underlying the interactions between different TFs in modulating senescence remain obscure. Previously, we discovered that plant ABS3 subfamily MATE transporter genes regulate senescence and senescence-associated transcriptional changes. In a genetic screen for mutants suppressing the accelerated senescence phenotype of the gain-of-function mutant abs3-1D, AUXIN RESPONSE FACTOR 2 (ARF2) and PHYTOCHROME-INTERACTING FACTOR 5 (PIF5) were identified as key TFs responsible for transcriptional regulation in the ABS3-mediated senescence pathway. ARF2 and PIF5 (as well as PIF4) interact directly and function interdependently to promote senescence, and they share common target genes such as key senescence promoting genes ORESARA 1 (ORE1) and STAY-GREEN 1 (SGR1) in the ABS3-mediated senescence pathway. In addition, we discovered reciprocal regulation between ABS3-subfamily MATEs and the ARF2 and PIF5/4 TFs. Taken together, our findings reveal a regulatory paradigm in which the ARF2-PIF5/4 functional module facilitates the transcriptional reprogramming in the ABS3-mediated senescence pathway.

MOR1/MAP215 acts synergistically with katanin to control cell division and anisotropic cell elongation in Arabidopsis.

The MAP215 family of microtubule (MT) polymerase/nucleation factors and the MT severing enzyme katanin are widely conserved MT-associated proteins (MAPs) across the plant and animal kingdoms. However, how these two essential MAPs coordinate to regulate plant MT dynamics and development remains unknown. Here, we identified novel hypomorphic alleles of MICROTUBULE ORGANIZATION 1 (MOR1), encoding the Arabidopsis thaliana homolog of MAP215, in genetic screens for mutants oversensitive to the MT-destabilizing drug propyzamide. Live imaging in planta revealed that MOR1-green fluorescent protein predominantly tracks the plus-ends of cortical MTs (cMTs) in interphase cells and labels preprophase band, spindle and phragmoplast MT arrays in dividing cells. Remarkably, MOR1 and KATANIN 1 (KTN1), the p60 subunit of Arabidopsis katanin, act synergistically to control the proper formation of plant-specific MT arrays, and consequently, cell division and anisotropic cell expansion. Moreover, MOR1 physically interacts with KTN1 and promotes KTN1-mediated severing of cMTs. Our work establishes the Arabidopsis MOR1-KTN1 interaction as a central functional node dictating MT dynamics and plant growth and development.

Cloning and functional identification of apple LATERAL ORGAN BOUNDARY DOMAIN 3 (LBD3) transcription factor in the regulation of drought and salt stress.

MAIN CONCLUSION: Overexpression of MdLBD3 in Arabidopsis reduced sensitivity to salt and drought stresses and was instrumental in promoting early flowering. Salt and drought stresses have serious effects on plant growth. LATERAL ORGAN BOUNDARY DOMAIN (LBD) proteins are a plant-specific transcription factors (TFs) family and play important roles in plants in resisting to abiotic stress. However, about the function of LBDs in apple and other woody plants is little known. In this study, protein sequences of the LBD family TFs in apples were identified which contained conserved LOB domains. The qRT-PCR analysis showed that the MdLBD3 gene was widely expressed in various tissues and organs. The subcellular localization assay showed that the MdLBD3 protein was localized in the nucleus. Ectopic expression of MdLBD3 in Arabidopsis positively regulated its salt and drought resistance, and promoted early flowering. Collectively, these results showed that MdLBD3 improved the abiotic stress resistance, plant growth and development. Overall, this study provided a new gene for breeding that can increase the abiotic stress tolerance in apple.

The AP2/ERF transcription factor MdDREB2A regulates nitrogen utilisation and sucrose transport under drought stress.

Drought stress is one of the main environmental factors limiting plant growth and development. Plants adapt to changing soil moisture by modifying root architecture, inducing stomatal closure, and inhibiting shoot growth. The AP2/ERF transcription factor DREB2A plays a key role in maintaining plant growth in response to drought stress, but the molecular mechanism underlying this process remains to be elucidated. Here, it was found that overexpression of MdDREB2A positively regulated nitrogen utilisation by interacting with DRE cis-elements of the MdNIR1 promoter. Meanwhile, MdDREB2A could also directly bind to the promoter of MdSWEET12, which may enhance root development and nitrogen assimilation, ultimately promoting plant growth. Overall, this regulatory mechanism provides an idea for plants in coordinating with drought tolerance and nitrogen assimilation to maintain optimal plant growth and development under drought stress.

Functional characterization of MdERF113 in apple.

The AP2/ERF family is an important class of transcription factors involved in plant growth and various biological processes. One of the AP2/ERF transcription factors, RAP2.6L, participates in various stresses responses. However, the function of RAP2.6L is largely unknown in apples (Malus domestica). In this study, an apple gene homologous to Arabidopsis AtRAP2.6L, MdERF113, was analyzed by bioinformatic characterization, gene expression analysis and subcellular localization assessment. MdERF113 was highly expressed in the sarcocarp and was responsive to hormonal signals and abiotic stresses. MdERF113-overexpression apple calli were less sensitive to low temperature, drought, salinity, and abscisic acid than wild-type. Subcellular localization revealed that MdERF113 was a nuclear-localized transcription factor, and yeast experiments confirmed that MdERF113 has no autonomous activation activity. Overall, this study indicated that MdERF113 plays a role in regulating plant growth under abiotic conditions.

The domain of unknown function 4005 (DUF4005) in an Arabidopsis IQD protein functions in microtubule binding.

The dynamic responses of microtubules (MTs) to internal and external signals are modulated by a plethora of microtubule-associated proteins (MAPs). In higher plants, many plant-specific MAPs have emerged during evolution as advantageous to their sessile lifestyle. Some members of the IQ67 domain (IQD) protein family have been shown to be plant-specific MAPs. However, the mechanisms of interaction between IQD proteins and MTs remain elusive. Here we demonstrate that the domain of unknown function 4005 (DUF4005) of the Arabidopsis IQD family protein ABS6/AtIQD16 is a novel MT-binding domain. Cosedimentation assays showed that the DUF4005 domain binds directly to MTs in vitro. GFP-labeled DUF4005 also decorates all types of MT arrays tested in vivo. Furthermore, we showed that a conserved stretch of 15 amino acid residues within the DUF4005 domain, which shares sequence similarity with the C-terminal MT-binding domain of human MAP Kif18A, is required for the binding to MTs. Transgenic lines overexpressing the DUF4005 domain displayed a spectrum of developmental defects, including spiral growth and stunted growth at the organismal level. At the cellular level, DUF4005 overexpression caused defects in epidermal pavement cell and trichome morphogenesis, as well as abnormal anisotropic cell elongation in the hypocotyls of dark-grown seedlings. These data establish that the DUF4005 domain of ABS6/AtIQD16 is a new MT-binding domain, overexpression of which perturbs MT homeostasis in plants. Our findings provide new insights into the MT-binding mechanisms of plant IQD proteins.

RUNX3-mediated circDYRK1A inhibits glutamine metabolism in gastric cancer by up-regulating microRNA-889-3p-dependent FBXO4.

BACKGROUND: Targeting glutamine metabolism is previously indicated as a potential and attractive strategy for gastric cancer (GC) therapy. However, the underlying mechanisms responsible for the modification of glutamine metabolism in GC cells have not been fully elucidated. Accordingly, the current study sought to investigate the physiological mechanisms of RUNX3-mediated circDYRK1A in glutamine metabolism of GC. METHODS: Firstly, GC tissues and adjacent normal tissues were obtained from 50 GC patients to determine circDYRK1A expression in GC tissues. Next, the binding affinity among RUNX3, circDYRK1A, miR-889-3p, and FBXO4 was detected to clarify the mechanistic basis. Moreover, GC cells were subjected to ectopic expression and knockdown manipulations of circDYRK1A, miR-889-3p, and/or FBXO4 to assay GC cell malignant phenotypes, levels of glutamine, glutamic acid, and α-KG in cell supernatant and glutamine metabolism-related proteins (GLS and GDH). Finally, nude mice were xenografted with GC cells to explore the in vivo effects of circDYRK1A on the tumorigenicity and apoptosis. RESULTS: circDYRK1A was found to be poorly expressed in GC tissues. RUNX3 was validated to bind to the circDYRK1A promoter, and circDYRK1A functioned as a miR-889-3p sponge to up-regulate FBXO4 expression. Moreover, RUNX3-upregulated circDYRK1A reduced levels of glutamine, glutamic acid, and α-KG, and protein levels of GLS and GDH, and further diminished malignant phenotypes in vitro. Furthermore, in vivo experimentation substantiated that circDYRK1A inhibited the tumorigenicity and augmented the apoptosis in GC. CONCLUSION: In conclusion, these findings highlighted the significance and mechanism of RUNX3-mediated circDYRK1A in suppressing glutamine metabolism in GC via the miR-889-3p/FBXO4 axis.

Overexpression of MdZAT5, an C2H2-Type Zinc Finger Protein, Regulates Anthocyanin Accumulation and Salt Stress Response in Apple Calli and Arabidopsis.

Zinc finger proteins are widely involved and play an important role in plant growth and abiotic stress. In this research, MdZAT5, a gene encoding C2H2-type zinc finger protein, was cloned and investigated. The MdZAT5 was highly expressed in flower tissues by qRT-PCR analyses and GUS staining. Promoter analysis showed that MdZAT5 contained multiple response elements, and the expression levels of MdZAT5 were induced by various abiotic stress treatments. Overexpression of MdZAT5 in apple calli positively regulated anthocyanin accumulation by activating the expressions of anthocyanin biosynthesis-related genes. Overexpression of MdZAT5 in Arabidopsis also enhanced the accumulation of anthocyanin. In addition, MdZAT5 increased the sensitivity to salt stress in apple calli. Ectopic expression of MdZAT5 in Arabidopsis reduced the expression of salt-stress-related genes (AtNHX1 and AtABI1) and improved the sensitivity to salt stress. In conclusion, these results suggest that MdZAT5 plays a positive regulatory role in anthocyanin accumulation and negatively regulates salt resistance.

Solid-liquid partitioning and variation of palladium in rainfall runoff.

Palladium (Pd) is most widely used in the production of automotive catalytic converters that serve to reduce toxic emissions from motor vehicles. The aim of this study was to analyze the solid-liquid partitioning and dynamic variation of Pd in rainfall runoff. The results showed that the partition coefficients (K) of Pd ranged from 0.05 to 8.55. Transport via suspended particulate matter as the main carrier was the main form of Pd migration in rainfall runoff. Pd phase distribution exhibited complex dynamic variations. The variation in Pd could be roughly divided into three categories, namely the W, M and N types, and the semi-U type was also observed. Rainfall characteristics and microenvironmental factors had a profound effect on Pd phase distribution in the first flush runoff. Under the influence of multifactor coupling, the impact of water quality parameters such as pH, Eh and Cl- on Pd partitioning was significantly weakened.

The temporal distribution of platinum group elements (PGEs) in PM2.5.

In this paper, Changji, Xinjiang, northwest China, was selected as the study area, and platinum group elements (PGEs) in PM2.5 were quantified by ICP-MS using microwave digestion. The results indicated that the average concentrations (and range) of Rh, Pd, and Pt in PM2.5 were 0.21 (n.d. -1.41) ng/m3, 8.09 (n.d. -59.50) ng/m3, and 0.12 (n.d. -0.83) ng/m3, respectively. The concentration of Pd was significantly higher than Rh and Pt. Moreover, the seasonal variations of Rh and Pd were the same: highest in summer and lower in other seasons. However, the seasonal variation of Pt was opposite to that of Rh and Pd: highest in winter and lower in other seasons. Seasonal differences in emission sources of PGEs and the climatic characteristics of arid regions played important roles in the seasonal changes of PGEs. Rh and Pd had a common source and similar diurnal variation. The major influencing factors were traffic volume and meteorological conditions. The diurnal variation regularity of Pt was different from Rh and Pd. The superimposed effect of vehicle exhaust emissions and coal-fired emissions was the main reason why the diurnal variation of Pt was more complicated than those of Rh and Pd. The diurnal concentration of Pt varied with the seasons. It is caused by seasonal coal combustion and meteorological conditions.

ABNORMAL SHOOT 6 interacts with KATANIN 1 and SHADE AVOIDANCE 4 to promote cortical microtubule severing and ordering in Arabidopsis.

Plant interphase cortical microtubules (cMTs) mediate anisotropic cell expansion in response to environmental and developmental cues. In Arabidopsis thaliana, KATANIN 1 (KTN1), the p60 catalytic subunit of the conserved MT-severing enzyme katanin, is essential for cMT ordering and anisotropic cell expansion. However, the regulation of KTN1-mediated cMT severing and ordering remains unclear. In this work, we report that the Arabidopsis IQ67 DOMAIN (IQD) family gene ABNORMAL SHOOT 6 (ABS6) encodes a MT-associated protein. Overexpression of ABS6 leads to elongated cotyledons, directional pavement cell expansion, and highly ordered transverse cMT arrays. Genetic suppressor analysis revealed that ABS6-mediated cMT ordering is dependent on KTN1 and SHADE AVOIDANCE 4 (SAV4). Live imaging of cMT dynamics showed that both ABS6 and SAV4 function as positive regulators of cMT severing. Furthermore, ABS6 directly interacts with KTN1 and SAV4 and promotes their recruitment to the cMTs. Finally, analysis of loss-of-function mutant combinations showed that ABS6, SAV4, and KTN1 work together to ensure the robust ethylene response in the apical hook of dark-grown seedlings. Together, our findings establish ABS6 and SAV4 as positive regulators of cMT severing and ordering, and highlight the role of cMT dynamics in fine-tuning differential growth in plants.

Variation in palladium and water quality parameters and their relationship in the urban water environment.

Palladium (Pd) is widely used in vehicle exhaust catalysts (VECs) to reduce toxic emissions from motor vehicles. The study aimed to quantitatively determine Pd content and water quality parameters, to analyze the variation differences and to explore the effect of water quality parameters on Pd content in the urban water environment system (wet deposition-rainfall runoff-receiving water body-estuary) of the city of Haikou, Hainan Island, China. The method used in this study included microwave digestion under high pressure and temperature, analysis by inductively coupled plasma mass spectrometry, quality control of the experimental procedure and guaranteed recovery (85% -125%). The results showed that the dissolved Pd average content in the urban water environment system was the highest in rainfall runoff (4.93 ng/L), followed by that in the receiving water body (4.56 ng/L), and it was the lowest in wet deposition (0.1 ng/L). The suspended Pd average content was the highest in the estuary (2.83 ng/L), followed by that in rainfall runoff (1.26 ng/L), and it was the lowest in wet deposition (6 × 10-4 ng/L). The particle-water partition ratio of the estuary Pd was the highest (1.26), followed by that of Pd in rainfall runoff (0.26). The particle-water partition ratio of the wet deposition Pd was the lowest (6 × 10-3). The dissolved Pd was correlated with the pH, Cl-, and total suspended solids (TSS) (correlation coefficient = 0.52, -0.68, 0.39, p < 0.05; regression coefficient = 1.27, -1.39, 0.01). The suspended Pd was only correlated with Cl- and TSS (correlation coefficient = -0.36, 0.76, p < 0.05; regression coefficient = -1.45, 0.01). Cl- and TSS were the most closely related to Pd in the water environment system. Although individual factors such as pH, Cl-, and TSS had certain migration and transformation effects on Pd in the wet deposition-rainfall runoff-receiving water body-estuary system, the probability of strong correlations was not high. In particular, Eh was not related to the dissolved nor suspended Pd content (correlation coefficient = 0.14, 0.13), which may be due to the synergistic effect of the multiple physical factors on Pd. This study was helpful to better understand the environmental behavior of Pd and provided important theoretical support for the prevention and protection against urban water environmental pollution.

[Regulatory effect of the pannexin1 channel on invasion and migration of testicular cancer Tcam-2 cells and its possible mechanism].

OBJECTIVE: To investigate the role of the pannexin-1 (Panx1) protein in the invasion and migration of testicular cancer Tcam-2 cells and its possible action mechanism. METHODS: Tcam-2 cells were treated with carbenoxolone (CBX) at 100 µmol/L and probenecid (PBN) 200 µmol/L. Then the intercellular fluorescence transmission was assessed by real-time fluorescence assay, the extracellular ATP concentration measured by chemi-luminescence immunoassay, the invasive and migratory abilities of the Tcam-2 cells detected by Transwell assay, and the expressions of the proteins Panx1, p-ERK1/2, ERK1/2, vimentin, MMP-9 and E-cadherin in the TM3 Leydig cells and testicular cancer Tcam-2 cells determined by Western blot. RESULTS: Western blot showed that the expression of the Panx1 protein was significantly higher in the testicular cancer Tcam-2 cells than in the TM3 Leydig cells (2.79 ± 0.17 vs 1.00 ± 0.06, P<0.05). The rates of intercellular fluorescence transmission in the Tcam-2 cells treated with CBX and PBN were markedly decreased as compared with the blank control group (ï¼»61.54 ± 3.30ï¼½% and ï¼»68.06 ± 4.03ï¼½% vs ï¼»99.50 ± 3.12ï¼½%, P<0.01), and so were the extracellular ATP concentrations (ï¼»57.06 ± 5.80ï¼½% and ï¼»56.42 ± 7.70ï¼½% vs ï¼»110 ± 8.16ï¼½%, P<0.01). The numbers of migrated Tcam-2 cells in the CBX and PBN groups were significantly reduced in comparison with that in the control (11.5 ± 1.11 and 8.25 ± 1.23 vs 331.00 ± 30.80, P<0.05), and so were those of the invaded ones (11.75 ± 3.77 and 11.5 ± 3.5 vs 89.00 ± 13.09, P<0.01). CBX and PBN significantly down-regulated the expression of p-ERK1/2 as compared with that in the blank control group (0.538 ± 0.05 and 0.476 ± 0.02 vs 0.98 ± 0.03, P<0.05), as well as those of vimentin (0.541 ± 0.09 and 0.705 ± 0.07, P<0.01) and MMP-9 (0.439 ± 0.08 and 0.557 ± 0.065, P<0.01) but up-regulated that of E-cadherin (3.896 ± 0.06 and 3.551 ± 0.04, P<0.01). CONCLUSIONS: The Panx1 protein is highly expressed in testicular cancer Tcam-2 cells. CBX and PBN can inhibit the function of the panneixn1 channel and reduce the invasive and migratory abilities of the Tcam-2 cells, which is associated with the decreased expression of the p-ERK1/2 protein.

[Expressions of pannexin proteins in I-10 Leydig tumor cells and TM3 Leydig cells and their regulatory effect on the channel function in mice].

OBJECTIVE: To investigate the expressions of the pannexin (Panx) proteins in I-10 Leydig tumor cells and TM3 Leydig cells and their regulatory effect on the Panx channel function in mice. METHODS: The expressions of the Panx-1 and Panx-2 proteins in the mouse Leydig tumor cells were determined by Western blot. The I-10 Leydig tumor cells were treated with carbenoxolone (CBX) at 100 µmol/L or probenecid (PBN) at 200 µmol/L, the fluorescence resonance energy transfer (FRET) detected by time-lapse fluorescence imaging, and the extracellular adenosine 5'-triphosphate (eATP) level measured with the commercial detection kit. Molecular biological methods were used to interfere with shRNA and overexpress mPanx-1 the Panx-1 gene and regulate the expression and function of the Panx-1 protein. RESULTS: The expressions of Panx-1 (ï¼»289.5 ± 55.8ï¼½%) and Panx-2 (ï¼»264.5 ± 24.6ï¼½%) were significantly increased in the I-10 Leydig tumor cells as compared with those in the normal TM3 Leydig cells (both P < 0.05). FRET was remarkably reduced after treated with CBX (ï¼»87.5 ± 17.7ï¼½%) and PBN (ï¼»89.3 ± 14.3ï¼½%) in comparison with that in the control group (both P < 0.01). At 8, 16 and 24 hours, the eATP level was decreased by (57.3 ± 7.2)%, (56.4 ± 9.6)% and (63.4 ± 6.4)% in the CBX group (P < 0.01) and (61.7 ± 2.5)%, (35.8 ± 1.6)% and (13.5 ± 8.3)% in the PBN group (P < 0.01). Molecular biological treatment down-regulated the expression of Panx-1 by (38.3 ± 5.2)% and (31.8 ± 5.1)% in the shRNA1 and shRNA2 groups, respectively (both P < 0.01), but up-regulated that of Panx-1 by (128.4 ± 7.5)% in the mPanx-1 group (P < 0.01) as compared with the negative control. FRET was reduced by (72.4 ± 39.4)% in the shRNA group (P < 0.01) and the eATP level by (14.7 ± 0.1)%, (13.7 ± 0.3)% and (13.1 ± 0.3)% at 8, 16 and 24 hours, respectively (P < 0.01) while FRET elevated by (122.5 ± 17.1)% in the mPanx-1 group (P < 0.01) and the eATP level by (886.1 ± 82.1)%, (885.8 ± 83.3)% and (841.5 ± 21.8)% at 8, 16 and 24 hours, respectively (P < 0.01). CONCLUSIONS: The expressions of Panx-1 and Panx-2 are increased in I-10 mouse Leydig tumor cells, and inhibiting the Panx channel with CBX, PBN and shRNA reduces FRET and the eATP level in the I-10 cells.

Tumor conspicuity enhancement-based segmentation model for liver tumor segmentation and RECIST diameter measurement in non-contrast CT images.

BACKGROUND AND OBJECTIVE: Liver tumor segmentation (LiTS) accuracy on contrast-enhanced computed tomography (CECT) images is higher than that on non-contrast computed tomography (NCCT) images. However, CECT requires contrast medium and repeated scans to obtain multiphase enhanced CT images, which is time-consuming and cost-increasing. Therefore, despite the lower accuracy of LiTS on NCCT images, which still plays an irreplaceable role in some clinical settings, such as guided brachytherapy, ablation, or evaluation of patients with renal function damage. In this study, we intend to generate enhanced high-contrast pseudo-color CT (PCCT) images to improve the accuracy of LiTS and RECIST diameter measurement on NCCT images. METHODS: To generate high-contrast CT liver tumor region images, an intensity-based tumor conspicuity enhancement (ITCE) model was first developed. In the ITCE model, a pseudo color conversion function from an intensity distribution of the tumor was established, and it was applied in NCCT to generate enhanced PCCT images. Additionally, we design a tumor conspicuity enhancement-based liver tumor segmentation (TCELiTS) model, which was applied to improve the segmentation of liver tumors on NCCT images. The TCELiTS model consists of three components: an image enhancement module based on the ITCE model, a segmentation module based on a deep convolutional neural network, and an attention loss module based on restricted activation. Segmentation performance was analyzed using the Dice similarity coefficient (DSC), sensitivity, specificity, and RECIST diameter error. RESULTS: To develop the deep learning model, 100 patients with histopathologically confirmed liver tumors (hepatocellular carcinoma, 64 patients; hepatic hemangioma, 36 patients) were randomly divided into a training set (75 patients) and an independent test set (25 patients). Compared with existing tumor automatic segmentation networks trained on CECT images (U-Net, nnU-Net, DeepLab-V3, Modified U-Net), the DSCs achieved on the enhanced PCCT images are both improved compared with those on NCCT images. We observe improvements of 0.696-0.713, 0.715 to 0.776, 0.748 to 0.788, and 0.733 to 0.799 in U-Net, nnU-Net, DeepLab-V3, and Modified U-Net, respectively, in terms of DSC values. In addition, an observer study including 5 doctors was conducted to compare the segmentation performance of enhanced PCCT images with that of NCCT images and showed that enhanced PCCT images are more advantageous for doctors to segment tumor regions. The results showed an accuracy improvement of approximately 3%-6%, but the time required to segment a single CT image was reduced by approximately 50 %. CONCLUSIONS: Experimental results show that the ITCE model can generate high-contrast enhanced PCCT images, especially in liver regions, and the TCELiTS model can improve LiTS accuracy in NCCT images.

Brassinosteroids biosynthetic gene MdBR6OX2 regulates salt stress tolerance in both apple and Arabidopsis.

Salt stress is a critical limiting factor for fruit yield and quality of apples. Brassinosteroids (BRs) play an important role in response to abiotic stresses. In the present study, application of 2,4- Epicastasterone on seedlings of Malus 'M9T337' and Malus domestica 'Gala3' alleviated the physiological effects, such as growth inhibition and leaf yellowing, induced by salt stress. Further analysis revealed that treatment with NaCl induced expression of genes involved in BR biosynthesis in 'M9T337' and 'Gala3'. Among which, the expression of BR biosynthetic gene MdBR6OX2 showed a three-fold upregulation upon salt treatment, suggesting its potential role in response to salt stress in apple. MdBR6OX2, belonging to the CYP450 family, contains a signal peptide region and a P450 domain. Expression patterns analysis showed that the expression of MdBR6OX2 can be significantly induced by different abiotic stresses. Overexpressing MdBR6OX2 enhanced the tolerance of apple callis to salt stress, and the contents of endogenous BR-related compounds, such as Typhastero (TY), Castasterone (CS) and Brassinolide (BL) were significantly increased in transgenic calli compared with that of wild-type. Extopic expression of MdBR6OX2 enhanced tolerance to salt stress in Arabidopsis. Genes associated with salt stress were significantly up-regulated, and the contents of BR-related compounds were significantly elevated under salt stress. Our data revealed that BR-biosynthetic gene MdBR6OX2 positively regulates salt stress tolerance in both apple calli and Arabidopsis.

Exosomal circ_0091741 promotes gastric cancer cell autophagy and chemoresistance via the miR-330-3p/TRIM14/Dvl2/Wnt/ß-catenin axis.

The importance of cancer cell-released exosomes in the treatment of various cancers has been well-characterized. The current study aims to examine the potential biological functions of gastric cancer (GC) cell-released exosomes delivering a novel circRNA circ_0091741 in GC and the underlying molecular mechanism. Expression of circ_0091741 was examined in the GC cells, (OXA)-resistant HGC-27 (HGC-27/OXA) cells, and isolated exosomes, after which its downstream miRNA was analyzed. The role and mechanism of the circ_0091741 transmitted by GC cells-derived exosomes in GC cell autophagy and chemoresistance were assessed using various molecular biological methods. A mouse tumor xenograft model was prepared to discern the effect of circ_0091741 on tumorigenesis in vivo. GC cells and their exosomes were characterized by upregulated circ_0091741 expression. circ_0091741 transferred by GC cell-derived exosomes induced the autophagy and OXA resistance of GC cells. circ_0091741 obstructed the binding of miR-330-3p to TRIM14 and increased the expression of TRIM14. TRIM14 could cause activation of the Wnt/ß-catenin signaling pathway by stabilizing Dvl2. By this mechanism, the autophagy and OXA resistance of GC cells were augmented. In vivo assay unfolded that orthotopic implantation of exosomal circ_0091741 overexpressed GC cells into nude mice enhanced tumorigenesis. In conclusion, our study emphasized the promotive role of exosomal circ_0091741 in autophagy and chemoresistance of GC cells, thus laying the basis for the development of novel therapeutic targets for GC treatment.

Estimation and potential ecological risk assessment of multiphase PAEs in mangrove wetlands in Dongzhai Harbor, Hainan.

With the application of plastic products, phthalates now widely occur in various environmental media. A large number of ecological risk assessment experiments have only been carried out on a single medium such as water or sediment. There are few reports of ecological risk assessments based on the phase states of phthalic acid esters (PAEs) such as the free dissolved state and the dissolved organic carbon (DOC) adsorption state. In this study, the concentrations of the free dissolved state, the DOC adsorption state, and the easily released PAEs in the sediments, as well as the dissolved organic carbon release potential and their influencing factors were calculated in the Dongzhaigang water body. The potential ecological risks posed by state-of-the-art PAEs were investigated. The average concentration of six freely dissolved PAEs in water was 0.542 (0.226-1.115) µg/L, accounting for 76.3 % of the total PAEs. The PAEs with the highest concentrations in the free dissolved state were di-n-butyl phthalate (DBP, 0.383 µg/L), followed by Di(2-ethylhexyl) phthalate (DEHP, 0.094 µg/L). The average concentration of all six PAEs (∑6PAEs) adsorbed by the DOC in the water was 0.172 µg/L, accounting for 23.74 % of all of the PAEs. The DOC-adsorbed DEHP (0.148 µg/L) accounted for about 86 % of the six adsorbed PAEs. Sediment organic carbon may affect the release potential of the DOC through changing the soluble organic carbon concentration. Most types of PAEs in water posed low risk to organisms. However, DBP posed low and medium risk to algae and crustaceans, and medium risk to fish. Medium or high risk of DEHP to algae, crustaceans and fish was observed. The high ecological risk of PAEs related to sediments were only found at S13 and S14. Generally, the potential ecological risk of PAEs in sediment was more stable than that in water bodies.

Variation in the concentration of particulate Pd in the Nandu River Estuary during spring-neap tides.

Estuaries are environmental systems with great resource potential and environmental benefits. This study investigates the role of particulate palladium (Pd) in the Nandu River Estuary in the enrichment of estuarine geochemical processes during spring-neap tides. Particulate Pd was found to show different characteristics during spring-neap tides, with the hydrodynamic condition being one of the key factors causing the difference. In addition, particulate Pd showed a decreasing trend while moving from the mouth to the upstream. The highest value of particulate Pd was 35.32 ng L-1, which occurred at the intersection of the mainstream and the branch during the neap tide, and the lowest value was 0.86 ng·L-1, which occurred in the far mouth area during the spring tide. The concentrations of particulate Pd during the neap and spring tides were 5.53 (1.01-35.32) ng·L-1 and 2.33 (0.86-5.22) ng·L-1, respectively. With the exception of stations 1, 5, 10, 11, and 15, the concentration of particulate Pd during the neap tide was greater than that during the spring tide. The variation in the particulate Pd was inconsistent between the spring tide and the neap tide, and the fluctuation in each study section during the neap tide was greater than that during the spring tide. In addition, since the emissions from catalytic converter are in the form of nanoparticles, they are difficult to be dissolve in natural water, and therefore, the concentration of particulate Pd was obviously greater in the waters near large bridges and main roads. An analysis of the physical and chemical properties of the water showed that Cl- easily combined with dissolved Pd and was one of the important factors that affected the concentration of particulate Pd. In addition, DO and Eh had little effect on the change in the particulate Pd during the tidal cycle, and pH had a significant positive correlation with particulate Pd.

A generic fundus image enhancement network boosted by frequency self-supervised representation learning.

Fundus photography is prone to suffer from image quality degradation that impacts clinical examination performed by ophthalmologists or intelligent systems. Though enhancement algorithms have been developed to promote fundus observation on degraded images, high data demands and limited applicability hinder their clinical deployment. To circumvent this bottleneck, a generic fundus image enhancement network (GFE-Net) is developed in this study to robustly correct unknown fundus images without supervised or extra data. Levering image frequency information, self-supervised representation learning is conducted to learn robust structure-aware representations from degraded images. Then with a seamless architecture that couples representation learning and image enhancement, GFE-Net can accurately correct fundus images and meanwhile preserve retinal structures. Comprehensive experiments are implemented to demonstrate the effectiveness and advantages of GFE-Net. Compared with state-of-the-art algorithms, GFE-Net achieves superior performance in data dependency, enhancement performance, deployment efficiency, and scale generalizability. Follow-up fundus image analysis is also facilitated by GFE-Net, whose modules are respectively verified to be effective for image enhancement.