ABSTRACT
Gibberellic acids (GAs) are a group of endogenous phytohormones that play important roles in plant growth and development. SLENDER RICE (SLR) serves as a vital component of the DELLA gene family, which plays an irreplaceable role in regulating plant flowering and height, as well as stress responses. SLR gene has not been reported in mango, and its function is unknown. In present study, two DELLA subfamily genes MiSLR1 and MiSLR2 were identified from mango. MiSLR1 and MiSLR2 were highly expressed in the stems of the juvenile stage, but were expressed at a low level in flower buds and flowers. Gibberellin treatment could up-regulate the expression of MiSLR1 and MiSLR2 genes, but gibberellin biosynthesis inhibitor prohexadione-calcium (Pro-Ca) and paclobutrazol (PAC) treatments significantly down-regulated the expression of MiSLR1, while MiSLR2 was up-regulated. The expression levels of MiSLR1 and MiSLR2 were up-regulated under both salt and drought treatments. Overexpression of MiSLR1 and MiSLR2 genes significantly resulted early flowering in transgenic Arabidopsis and significantly up-regulated the expression levels of endogenous flower-related genes, such as SUPPRESSOR OF CONSTANS1 (SOC1), APETALA1 (AP1), and FRUITFULL (FUL). Interestingly, MiSLR1 significantly reduced the height of transgenic plants, while MiSLR2 gene increased. Overexpression of MiSLR1 and MiSLR2 increased seed germination rate, root length and survival rate of transgenic plants under salt and drought stress. Physiological and biochemical detection showed that the contents of proline (Pro) and superoxide dismutase (SOD) were significantly increased, while the contents of malondialdehyde (MDA) and H2O2 were significantly decreased. Additionally, protein interaction analysis revealed that MiSLR1 and MiSLR2 interacted with several flowering-related and GA-related proteins. The interaction between MiSLR with MiGF14 and MiSOC1 proteins was found for the first time. Taken together, the data showed that MiSLR1 and MiSLR2 in transgenic Arabidopsis both regulated the flowering time and plant height, while also acting as positive regulators of abiotic stress responses.
ABSTRACT
Starch degradation often coincides with its chemical modification, and understanding how chemical modification influences starch degradation is vital for determining the properties of the resultant modified products. This work investigates the effect of oxidation on starch molecular degradation, examining factors such as oxidation degree, reaction kinetics, and degradation patterns during 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated starch oxidation under varying conditions, including reaction time, pH, temperature, and concentrations of NaBr, TEMPO, and NaClO. Results emphasize that extended reaction durations primarily lead to ß-elimination, causing α-1,4 linkage cleavages. pH 8.5 favored non-selective oxidation, while pH 11 enhanced ß-elimination, both slowing the reaction rate and severely damaging starch chains (Mw of 8.8 × 105 g/mol and 7.2 × 105 g/mol, respectively). Elevated temperature from 0 to 30 °C significantly expedited both selective and non-selective oxidation, dramatically reducing molecular mass to 8.1 × 105 g/mol. Increasing concentrations of NaBr and TEMPO boost the reaction rate with minimal impact on molecular mass. Meanwhile, increasing NaClO concentration from 0.2 to 2.2 mmol/g-starch not only affects the reaction rate but also reinforces ß-elimination, enhancing molecular degradation. This study is insightful for starch modification to achieve desired oxidation levels and chain lengths by controlling reaction conditions, offering potential advancements in oxidized starch-based materials like nano micelles.
Subject(s)
Cyclic N-Oxides , Oxidation-Reduction , Starch , Temperature , Starch/chemistry , Cyclic N-Oxides/chemistry , Kinetics , Hydrogen-Ion Concentration , Molecular WeightABSTRACT
Accurate prediction of dissolved oxygen (DO) dynamics is crucial for understanding the influence of environmental factors on the stability of aquatic ecosystem. However, limited research has been conducted to determine the optimal frequency of water quality monitoring that ensures continuous assessment of water health while minimizing costs. To address these challenges, the present study developed a hybrid stochastic hydrological model (i.e., ARIMA-GARCH hybrid model) and machine learning (ML) models. The objective of this study is to identify the best-performing model and establish the optimal monitoring frequency. Results revealed that high-frequency DO monitoring data exhibit greater variability compared to low-frequency data. Moreover, the ARIMA-GARCH model demonstrates promising potential in predicting DO concentrations for low-frequency monitoring data, surpassing ML models in performance. Furthermore, increasing the monitoring frequency significantly improves the prediction accuracy of models, regardless of whether point (with lower R2 values of 0.64 and 0.51 for daily detection than these of every 15 min (0.96 and 0.99) at CHQ and LHT, respectively) or interval predictions (with RIW higher values of 2.00 and 1.55 for daily detection higher than these of 0.02 and 0.16 in every 15 min at CHQ and LHT, respectively) are considered. Additionally, a 4 hourly monitoring frequency was found to be optimal for water quality assessment using each model. These findings identify the superior performing of the ARIMA-GARCH model and highlight the crucial role of monitoring frequency in enhancing DO prediction and improving model performance.
ABSTRACT
The aim of the present research is to explore the biological function and mechanism of circ_0082319 in HCC progression. Circ_0082319, microRNA-505-3p (miR-505-3p), protein tyrosine kinase 2 (PTK2), and human antigen R (HuR, also known as ELAVL1) level were detected by real-time quantitative polymerase chain reaction. Cell viability, proliferation, apoptosis, invasion, and angiogenesis were measured using (4-5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry, transwell, and tube formation assays. Protein levels of c-Myc, MMP2, PTK2, and HuR were examined using western blot. The glycolysis levels were assessed using specific kits. Binding between miR-505-3p and circ_0082319 or PTK2 was predicted by Starbase and verified by a dual-luciferase reporter and RNA immunoprecipitation assays. The biological role of circ_0082319 on HCC tumor growth was examined using xenograft tumor model in vivo. Circ_0082319, PTK2, and HuR were highly expressed, and miR-505-3p was reduced in HCC samples and cell lines. Moreover, the knockdown of circ_0082319 might repress HCC cell proliferation, invasion, angiogenesis, and induce apoptosis in vitro. In mechanism, circ_0082319 served as a sponge of miR-505-3p to regulate PTK2 expression. HuR expedited circ_0082319 expression in HCC cells. HuR-mediated circ_0082319 might accelerate HCC cell proliferation, invasion, angiogenesis, and suppress apoptosis by the miR-505-3p/PTK2 axis, hinting at a promising therapeutic target for HCC treatment.
ABSTRACT
Studies have shown that the m6A reader primarily affects genes expression by participating in the regulation of mRNA localization, splicing, degradation, translation, and other metabolic processes. Previously, we discovered that the apple (Malus domestica) m6A reader MhYTP2 bound with and destabilized m6A-modified MdMLO19 mRNA. In addition, it enhanced the translation efficiency of m6A-modified mRNA of MdGDH1L, encoding a glutamate dehydrogenase, which confers resistance to powdery mildew. In this study, we report the function of MhYTP2 in the regulation of resistance to low nitrogen (N). The overexpression of MhYTP2 enhances the resistance of apple to low N. We show that MhYTP2 binds with and stabilizes the mRNAs of MdALN, which participates in the allantoin catabolic process and cellular response to N starvation in apple; MdPIDL, which participates in root hair elongation; MdTTG1, which is involved in the differentiation process of trichomes; and MdATG8A, which is a core participant in the regulation of autophagy. In addition, MhYTP2 accelerates the degradation of MdRHD3 mRNA, which regulates root development. RNA immunoprecipitation-seq and electrophoretic mobility shift assays show that the mRNAs of MdALN, MdATG8A, MdPIDL, MdTTG1, and MdRHD3 are the direct targets of MhYTP2. Overexpressing or knocking down the above genes in MhYTP2 overexpressing plants dismisses the function of MhYTP2 under low N, suggesting the role of MhYTP2 is dependent on those genes. Together, these results demonstrate that MhYTP2 enhances the resistance of apple to N deficiency by affecting the stability of the bound mRNAs.
ABSTRACT
Glomerella leaf spot (GLS), caused by the fungal pathogen Colletotrichum fructicola, significantly threatens apple production. Some resistances to plant disease are mediated by the accumulation of nucleotide-binding site and leucine-rich repeat (NBS-LRR) proteins that are encoded by a major class of plant disease resistance genes (R genes). However, the R genes that confer resistance to GLS in apple remain largely unclear. Malus hupehensis YT521-B homology domain-containing protein 2 (MhYTP2) was identified as an N6 -methyladenosine RNA methylation (m6 A) modified RNA reader in our previous study. However, whether MhYTP2 binds to mRNAs without m6 A RNA modifications remains unknown. In this study, we discovered that MhYTP2 exerts both m6 A-dependent and -independent functions by analysing previously obtained RNA immunoprecipitation sequencing results. The overexpression of MhYTP2 significantly reduced the resistance of apple to GLS and down-regulated the transcript levels of some R genes whose transcripts do not contain m6 A modifications. Further analysis indicated that MhYTP2 binds to and reduces the stability of MdRGA2L mRNA. MdRGA2L positively regulates resistance to GLS by activating salicylic acid signalling. Our findings revealed that MhYTP2 plays an essential role in the regulation of resistance to GLS and identified a promising R gene, MdRGA2L, for use in developing apple cultivars with GLS resistance.
Subject(s)
Malus , Phyllachorales , Phyllachorales/genetics , Phyllachorales/metabolism , Malus/microbiology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Base Sequence , Signal Transduction , Plant Diseases/genetics , Plant Diseases/microbiology , Disease Resistance/genetics , Plant Proteins/genetics , Plant Proteins/metabolismABSTRACT
As a type of phytoestrogen, lignans have attracted attention in recent years for their nutritional functions. To investigate the effects of lignans on the structural and nutritional functions of starch, honokiol (HK) and arctiin (AC) were complexed with rice starch respectively under high-pressure homogenization (UHPH) (UHPHRS/HK and UHPHRS/AC). The results showed that both HK and AC could form inclusive complexes with rice starch via non-covalent bonding (hydrophobic interaction and hydrogen bonds), and these complexes could further form V-type crystals and aggregates, which reduced the starch digestibility as well as endowing them with the ability to retard glucose release and bind sodium cholate. Interestingly, due to its smaller molecular size, HK could induce starch to form a more compact structure than AC, leading to better nutritional functions. When the addition of HK/AC reached 8%, the resistant starch content could reach 26% and 19.8%, respectively. Meanwhile, the glucose dialysis retardation index could increase to 17.2% and 14.8%, respectively, and the sodium cholate-binding capacity could increase to 33.1 mg g-1 and 21.8 mg g-1, respectively. These results demonstrated that UHPH with lignans' molecular interaction could be beneficial for controlling the nutritional functions of starch products with the desired digestibility.
Subject(s)
Lignans , Oryza , Allyl Compounds , Biphenyl Compounds , Glucose/metabolism , Lignans/metabolism , Oryza/chemistry , Phenols , Phytoestrogens/metabolism , Resistant Starch , Sodium Cholate , Starch/chemistryABSTRACT
N6 -methyladenosine (m6 A) reader protein plays an important role in trichome morphology, developmental timing and morphogenesis in Arabidopsis. However, the function of m6 A readers in plant-microbe interaction remains unclear. Here, a Malus YTH-domain family protein MhYTP2 was initially characterized as an m6 A reader. MhYTP2 overexpression increased mRNA m6 A modification level and translation efficiency. The m6 A in the exon regions appeared to destabilize the mRNAs, whereas m6 A in the untranslated regions positively correlated with the associated mRNA abundance. MhYTP2 overexpression enhanced apple powdery mildew resistance, possibly by rapidly degrading the bound mRNAs of MdMLO19 and MdMLO19-X1 and improving the translation efficiency of the antioxidant genes. To conclude, the results shed light on the apple m6 A profile, the effect of MhYTP2 on m6 A profile, and the m6 A roles in MdMLO19 and MdMLO19-X1 mRNAs stability and glutamate dehydrogenase 1-like MdGDH1L mRNA translation efficiency.
Subject(s)
Arabidopsis , Malus , Antioxidants , Arabidopsis/genetics , Malus/genetics , Plant Diseases/genetics , RNA Stability , RNA, Messenger/geneticsABSTRACT
Drought seriously affects the yield and quality of apples. γ-aminobutyric acid (GABA) plays an important role in the responses of plants to various stresses. However, the role and possible mechanism of GABA in the drought response of apple seedlings remain unknown. To explore the effect of GABA on apple seedlings under drought stress, seedlings of Malus hupehensis were treated with seven concentrations of GABA, and the response of seedlings under 15-day drought stress was observed. The results showed that 0.5 mM GABA was the most effective at relieving drought stress. Treatment with GABA reduced the relative electrical conductivity and MDA content of leaves induced by drought stress and significantly increased the relative water content of leaves. Exogenous GABA significantly decreased the stomatal conductance and intercellular carbon dioxide concentration and transpiration rate, and it significantly increased the photosynthetic rate under drought. GABA also reduced the accumulation of superoxide anions and hydrogen peroxide in leaf tissues under drought and increased the activities of POD, SOD, and CAT and the content of GABA. Exogenous treatment with GABA acted through the accumulation of abscisic acid (ABA) in the leaves to significantly decrease stomatal conductance and increase the stomatal closure rate, and the levels of expression of ABA-related genes PYL4, ABI1, ABI2, HAB1, ABF3, and OST1 changed in response to drought. Taken together, exogenous GABA can enhance the drought tolerance of apple seedlings.
Subject(s)
Abscisic Acid/pharmacology , Droughts , Gene Expression Regulation, Plant/drug effects , Malus/growth & development , Plant Proteins/metabolism , Seedlings/growth & development , gamma-Aminobutyric Acid/pharmacology , GABA Agents/pharmacology , Malus/drug effects , Malus/genetics , Malus/metabolism , Plant Growth Regulators/pharmacology , Plant Proteins/genetics , Seedlings/drug effects , Seedlings/genetics , Seedlings/metabolism , Stress, PhysiologicalABSTRACT
This study emphasized on structural alteration of rice starch-unsaturated fatty acid complexes by adding trans-2-dodecaenoic acid (t12), trans-oleic acid (t18), cis-oleic acid (c18) and linoleic acid (loa) with different concentration under high-pressure homogenization treatment, and further illustrated the underlying mechanism of modulating digestibility. Results showed that the complex primarily presented as V6 or type IIa polymorph; complex index, content of ordered structure and thermal stability appeared to be positively correlated to the concentration of unsaturated fatty acids. t12 was too mobile to form single helix, leading to the formation of loose matrix; t18 fitted better within the cavity of starch than c18, and formed structural domain with higher compactness and thermal stability; Rloa had lower complex index but higher degree of short-range order, and tended to form alternating amorphous and crystalline structure. The digestibility was higher in the order of Rloa, Rt18, Rc18 and Rt12.
Subject(s)
Fatty Acids, Unsaturated/chemistry , Lauric Acids/chemistry , Linoleic Acid/chemistry , Oleic Acid/chemistry , Oryza/chemistry , Starch/chemistry , Crystallization , Fractals , Hydrogen Bonding , Hydrolysis , Pressure , Spectroscopy, Fourier Transform Infrared , Thermodynamics , X-Ray DiffractionABSTRACT
Ethylene plays an important role in stress adaptation and fruit ripening. Acireductone dioxygenase (ARD) is pivotal for ethylene biosynthesis. However, the response of ARD to fruit ripening or cold stress is still unclear. In this study, we identified three members of Malus ARD family, and expression profile analysis revealed that the transcript level of MdARD4 was induced during apple fruit ripening and after apple plants were being treated with cold stress. To investigate its function in cold tolerance and fruit ripening, MdARD4 was ectopically expressed in Solanum lycopersicum cultivar 'Micro-Tom', which has been considered as an excellent model plant for the study of fruit ripening. At the cellular level, the MdARD protein expressed throughout Nicotiana benthamiana epidermal cells. Overexpression of MdARD4 in tomato demonstrated that MdARD4 regulates the ethylene and carotenoid signaling pathway, increases ethylene and carotenoid concentrations, and accelerates fruit ripening. Furthermore, MdARD4 increased the antioxidative ability and cold hardiness in tomato. To conclude, MdARD4 may potentially be used in apple breeding to accelerate fruit ripening and increase cold hardiness.
Subject(s)
Dioxygenases/genetics , Dioxygenases/metabolism , Malus/genetics , Solanum lycopersicum/growth & development , Carotenoids/metabolism , Cold-Shock Response , Ethylenes/biosynthesis , Evolution, Molecular , Fruit/genetics , Fruit/growth & development , Solanum lycopersicum/genetics , Phylogeny , Plant Breeding , Plant Proteins/genetics , Plant Proteins/metabolism , Plants, Genetically Modified/growth & developmentABSTRACT
Accurate groundwater depth forecasting is particularly important for human life and sustainable groundwater management in arid and semi-arid areas. To improve the groundwater forecasting accuracy, in this paper, a hybrid groundwater depth forecasting model using configurational entropy spectral analyses (CESA) with the optimal input is constructed. An original groundwater depth series is decomposed into subseries of different frequencies using the variational mode decomposition (VMD) method. Cross-correlation analysis and Shannon entropy methods are applied to select the optimal input series for the model. The ultimate forecasted values of the groundwater depth can be obtained from the various forecasted values of the selected series with the CESA model. The applicability of the hybrid model is verified using the groundwater depth data from four monitoring wells in the Xi'an of Northwest China. The forecasting accuracy of the models was evaluated based on the average relative error (RE), root mean square error (RMSE), correlation coefficient (R) and Nash-Sutcliffe coefficient (NSE). The results indicated that comparing with the CESA and autoregressive model, the hybrid model has higher prediction performance.
Subject(s)
Groundwater , China , Entropy , Forecasting , Humans , Water WellsABSTRACT
MhYTP1 is involved in post-transcriptional regulation as a member of YT521-homology (YTH) domain-containing RNA-binding proteins. We previously cloned MhYTP1 and found it participated in various biotic and abiotic stress responses. However, its function in long-term moderate drought has not been verified. Thus, we explored its biological role in response to drought. Under drought condition, the net photosynthesis rate (Pn) and water use efficiency (WUE) were significantly elevated in MhYTP1-overexpressing (OE) apple plants when compared with the non-transgenic (NT) controls. Further analysis indicated MhYTP1 expression was associated with elevated ABA content, increased stomatal density and reduced stomatal aperture. In addition, to gain insight into the function of stem-specific expression of MhYTP1, grafting experiments were performed. Interestingly, lower transpiration rate (Tr) and higher WUE were observed when transgenic plants were used as scions as opposed to rootstocks and when transgenic rather than NT plants were used as rootstocks, indicating MhYTP1 plays crucial roles in grafted plants. These results define a function for MhYTP1 in promoting tolerance to drought conditions, and suggest that MhYTP1 can serve as a candidate gene for future apple drought resistance breeding with the help of biotechnology.
Subject(s)
Abscisic Acid/metabolism , Malus/genetics , Plant Growth Regulators/metabolism , RNA-Binding Proteins/metabolism , Water/metabolism , Droughts , Gene Expression , Malus/physiology , Plant Components, Aerial/genetics , Plant Components, Aerial/physiology , Plant Proteins/genetics , Plant Proteins/metabolism , Plant Roots/genetics , Plant Roots/physiology , Plant Stomata/genetics , Plant Stomata/physiology , Plants, Genetically Modified , RNA-Binding Proteins/genetics , Stress, PhysiologicalABSTRACT
The first YTH domain-containing RNA binding protein (YTP) was found in rat, where it was related to oxidative stress. Unlike characterizations in yeast and animals, functions of plant YTPs are less clear. Malus hupehensis (Pamp.) Rehd. YTP1 and YTP2 (MhYTP1 and MhYTP2) are known to be active in leaf senescence and fruit ripening. However, no research has been published about their roles in stress responses. Here, we investigate the stress-related functions of MhYTP1 and MhYTP2 in Arabidopsis thaliana. Both of the two genes participated in salicylic acid (SA), jasmonic acid (JA), and abscisic acid (ABA) signaling and play roles in plant responses to oxidative stress, chilling, high temperature, high salinity, and mannitol induced physiological drought stress. Moreover, MhYTP1 plays leading roles in SA and ABA signaling, and MhYTP2 plays leading roles in JA signaling and oxidative stress responses. These results will fill a gap in our knowledge about plant YTPs and stress responses and provide a foundation for future attempts to improve stress tolerance in apple.
ABSTRACT
RNA binding proteins play important roles in plant responses to biotic and abiotic stresses. The YT521-B homology (YTH) domain-containing RNA binding protein (YTP) was first found in Rattus norvegicus and is related to oxygen-deficient stress. The Malus YTP gene family has 15 members. Results from their functional analysis will help researchers improve stress tolerance and fruit quality in apple. We cloned two homologous YTP family members in M. hupehensis - MhYTP1 and MhYTP2 - and identified their promoter regions that contain many cis-elements related to biotic and abiotic stresses. Both MhYTP1 and MhYTP2 can be induced by various treatments, e.g., methyl jasmonate (MeJA), salicylic acid (SA), abscisic acid (ABA), water-logging, water deficits, and high salinity. When compared with the wild type (WT), transgenic plants of 'GL-3' ('Royal Gala') apple that over-express MhYTP1 or MhYTP2 are more sensitive to D. mali infection, heat stress, and high salinity, more resistant to water-logging, chilling, drought and nutrition deficient conditions. All of these findings indicate that MhYTP1 and MhYTP2 participate in various biotic- and abiotic-stress responses.