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Sugars are involved in plant growth, fruit quality, and signaling perception. Therefore, understanding the mechanisms involved in soluble sugar accumulation is essential to understand fruit development. Here, we report that MdPFPβ, a pyrophosphate‐dependent phosphofructokinase gene, regulates soluble sugar accumulation by enhancing the photosynthetic performance and sugar‐metabolizing enzyme activities in apple (Malus domestica Borkh.). Biochemical analysis revealed that a basic helix‐loop‐helix (bHLH) transcription factor, MdbHLH3, binds to the MdPFPβ promoter and activates its expression, thus promoting soluble sugar accumulation in apple fruit. In addition, MdPFPβ overexpression in tomato influenced photosynthesis and carbon metabolism in the plant. Furthermore, we determined that MdbHLH3 increases photosynthetic rates and soluble sugar accumulation in apple by activating MdPFPβ expression. Our results thus shed light on the mechanism of soluble sugar accumulation in apple leaves and fruit: MdbHLH3 regulates soluble sugar accumulation by activating MdPFPβ gene expression and coordinating carbohydrate allocation. [ABSTRACT FROM AUTHOR]

With the expectation of finding new and effective antitumor drugs, a series of novel N‐(1H‐benzo[d]imidazole‐2‐yl)‐benzamide/benzenesulfonamide derivatives of dehydroabietic acid were synthesized and evaluated for cytotoxic activity against three human cancer cell lines (MCF‐7, HeLa, and HepG2 cells) and one human normal hepatocyte cell line (LO2). As a result, a number of derivatives showed moderate to good antitumor activities. Among them, compound 8h exhibited the most potent activities against three cancer cell lines with IC50 values of 0.87 ± 0.18, 9.39 ± 0.72, and 8.31 ± 0.64 μM, respectively, and was less active to normal hepatocyte LO2 cells. Further mechanism studies revealed that compound 8h could arrest the cell cycle of MCF‐7 cells at S phase and induce the apoptosis of MCF‐7 cells in ROS‐mediated mitochondrial pathway. [ABSTRACT FROM AUTHOR]

Tuning the magnetic anisotropy of metal ions remains highly interesting in the design of improved single‐molecule magnets (SMMs). We herein report synthetic, structural, magnetic, and computational studies of four mononuclear CoII complexes, namely [Co(hfac)2(MeCN)2] (1), [Co(hfac)2(Spy)2] (2), [Co(hfac)2(MBIm)2] (3), and [Co(hfac)2(DMF)2] (4) (MeCN=acetonitrile, hfac=hexafluoroacetylacetone, Spy=4‐styrylpyridine, MbIm=5,6‐dimethylbenzimidazole, DMF=N,N‐dimethylformamide), with distorted octahedral geometry constructed from hexafluoroacetylacetone (hfac) and various axial ligands. By a building block approach, complexes 2–4 were synthesized by recrystallization of the starting material of 1 from various ligands containing solution. Magnetic and theoretical studies reveal that 1–4 possess large positive D values and relative small E parameters, indicating easy‐plane magnetic anisotropy with significant rhombic anisotropy in 1–4. Dynamic alternative current (ac) magnetic susceptibility measurements indicate that these complexes exhibit slow magnetic relaxation under external fields, suggesting field‐induced single‐ion magnets (SIMs) of 1–4. These results provide a promising platform to achieve fine tuning of magnetic anisotropy through varying the axial ligands based on Co(II) bis(hexafluoroacetylacetonate) complexes. [ABSTRACT FROM AUTHOR]

Summary: Salicylic acid (SA) signalling plays an essential role in plant innate immunity. In this study, we identified a component in the SA signaling pathway in potato (Solanum tuberosum), the transcription factor StbZIP61, and characterized its function in defence against Phytophthora infestans. Expression of StbZIP61 was induced upon P. infestans infection and following exposure to the defense signaling hormones SA, ethylene and jasmonic acid. Overexpression of StbZIP61 increased the tolerance of potato plants to P. infestans while RNA interference (RNAi) increased susceptibility. Yeast two‐hybrid and pull down experiments revealed that StbZIP61 could interact with an NPR3‐like protein (StNPR3L) that inhibited its DNA‐binding and transcriptional activation activities. Moreover, StNPR3L interacted with StbZIP61 in an SA‐dependent manner. Among candidate genes involved in SA‐regulated defense responses, StbZIP61 had a significant impact on expression of StICS1, which encodes a key enzyme for SA biosynthesis. StICS1 transcription was induced upon P. infestans infection and this responsive expression to the pathogen was reduced in StbZIP61 RNAi plants. Accordingly, StICS1 expression was remarkably enhanced in StbZIP61‐overexpressing plants. Together, our data demonstrate that StbZIP61 functions in concert with StNPR3L to regulate the temporal activation of SA biosynthesis, which contributes to SA‐mediated immunity against P. infestans infection in potato. [ABSTRACT FROM AUTHOR]

Cell elongation and secondary wall deposition are two consecutive stages during cotton fiber development. The mechanisms controlling the progression of these two developmental phases remain largely unknown. Here, we report the functional characterization of the actin-bundling protein GhFIM2 in cotton fiber. Overexpression of GhFIM2 increased the abundance of actin bundles, which was accompanied with accelerated fiber growth at the fast-elongating stage. Meanwhile, overexpression of GhFIM2 could propel the onset of secondary cell wall biogenesis. These results indicate that the dynamic rearrangement of actin higher structures involving GhFIM2 plays an important role in the development of cotton fiber cells. [ABSTRACT FROM AUTHOR]

Summary Softening in fruit adversely impacts their edible quality and commercial value, leading to substantial economic losses during fruit ripening, long‐term storage, long‐distance transportation, and marketing. As the apple fruit demonstrates climacteric respiration, its firmness decreases with increasing ethylene release rate during fruit ripening and postharvest storage. However, the molecular mechanisms underlying ethylene‐mediated regulation of fruit softening in apple remain poorly understood. In this study, we identified a WRKY transcription factor (TF) MdWRKY31, which is repressed by ethylene treatment. Using transgenic approaches, we found that overexpression of MdWRKY31 delays softening by negatively regulating xyloglucan endotransglucosylase/hydrolases 2 (MdXTH2) expression. Yeast one‐hybrid (Y1H), electrophoretic mobility shift (EMSA), and dual‐luciferase assays further suggested that MdWRKY31 directly binds to the MdXTH2 promoter via a W‐box element and represses its transcription. Transient overexpression of ethylene‐induced MdNAC7, a NAC TF, in apple fruit promoted softening by decreasing cellulose content and increasing water‐soluble pectin content in fruit. MdNAC7 interacted with MdWRKY31 to form a protein complex, and their interaction decreased the transcriptional repression of MdWRKY31 on MdXTH2. Furthermore, MdNAC7 does not directly regulate MdXTH2 expression, but the protein complex formed with MdWRKY31 hinders MdWRKY31 from binding to the promoter of MdXTH2. Our findings underscore the significance of the regulatory complex NAC7–WRKY31 in ethylene‐responsive signalling, connecting the ethylene signal to XTH2 expression to promote fruit softening. This sheds light on the intricate mechanisms governing apple fruit firmness and opens avenues for enhancing fruit quality and reducing economic losses associated with softening. [ABSTRACT FROM AUTHOR]

Pathological cardiac hypertrophy, a common feature in various cardiovascular diseases, can be more effectively managed through combination therapies using natural compounds. Harmine, a β-carboline alkaloid found in plants, possesses numerous pharmacological functions, including alleviating cardiac hypertrophy. Similarly, Selenomethionine (SE), a primary organic selenium source, has been shown to mitigate cardiac autophagy and alleviate injury. To explores the therapeutic potential of combining Harmine with SE to treat cardiac hypertrophy. The synergistic effects of SE and harmine against cardiac hypertrophy were assessed in vitro with angiotensin II (AngII)-induced hypertrophy and in vivo using a Myh6 R404Q mouse model. Co-administration of SE and harmine significantly reduced hypertrophy-related markers, outperforming monotherapies. Transcriptomic and metabolic profiling revealed substantial alterations in key metabolic and signalling pathways, particularly those involved in energy metabolism. Notably, the combination therapy led to a marked reduction in the activity of key glycolytic enzymes. Importantly, the addition of the glycolysis inhibitor 2-deoxy-D-glucose (2-DG) did not further potentiate these effects, suggesting that the antihypertrophic action is predominantly mediated through glycolytic inhibition. These findings highlight the potential of SE and harmine as a promising combination therapy for the treatment of cardiac hypertrophy., (© 2024 The Author(s). Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

In the title compound, C(4)H(5)N(3)O(2), the nitro group is twisted with respect to the imidazole ring by a dihedral angle of 5.60 (2)°. Weak inter-molecular C-H⋯O and C-H⋯N hydrogen bonding is present in the crystal structure.

In the title compound, C(14)H(9)N(5)O(10), the two benzene rings are inclined at a dihedral angle of 14.81 (5)°, and the nitro groups are twisted with respect to the benzene rings to which they are attached, making dihedral angles of 57.89 (7), 14.93 (7), 62.58 (7), 2.80 (12) and 22.38 (12)°. Weak inter-molecular C-H⋯O hydrogen bonding is present in the crystal structure.

The title compound, C(14)H(8)N(6)O(12), is centrosymmetric, the mid-point of the central C-C bond being located on an inversion centre. Two of the three independent nitro groups are disordered over two sites, with a site-occupancy ratio of 0.513 (3):0.487 (3). Weak inter-molecular C-H⋯O hydrogen bonding is present in the crystal structure.