AtSRT1 regulates flowering by regulating flowering integrators and energy signals in Arabidopsis.

Epigenetic modifications, such as histone alterations, play crucial roles in regulating the flowering process in Arabidopsis, a typical long-day model plant. Histone modifications are notably involved in the intricate regulation of FLC, a key inhibitor of flowering. Although sirtuin-like protein and NAD+-dependent deacetylases play an important role in regulating energy metabolism, plant stress responses, and hormonal signal transduction, the mechanisms underlying their developmental transitions remain unclear. Thus, this study aimed to reveal how Arabidopsis NAD + -dependent deacetylase AtSRT1 affects flowering by regulating the expression of flowering integrators. Genetic and molecular evidence demonstrated that AtSRT1 mediates histone deacetylation by directly binding near the transcriptional start sites (TSS) of the flowering integrator genes FT and SOC1 and negatively regulating their expression by modulating the expression of the downstream gene LFY to inhibit flowering. Additionally, AtSRT1 directly down-regulates the expression of TOR, a glucose-driven central hub of energy signaling, which controls cell metabolism and growth in response to nutritional and environmental factors. This down-regulation occurs through binding near the TSS of TOR, facilitating the addition of H3K27me3 marks on FLC via the TOR-FIE-PRC2 pathway, further repressing flowering. These results uncover a multi-pathway regulatory network involving deacetylase AtSRT1 during the flowering process, highlighting its interaction with TOR as a hub for the coordinated regulation of energy metabolism and flowering initiation. These findings significantly enhance understanding of the complexity of histone modifications in the regulation of flowering.

A TTC19 mutation associated with progressive movement disorders and peripheral neuropathy: Case report and systematic review.

BACKGROUND: Mitochondrial complex III (CIII) deficiency is an autosomal recessive disease characterized by symptoms such as ataxia, cognitive dysfunction, and spastic paraplegia. Multiple genes are associated with complex III defects. Among them, the mutation of TTC19 is a rare subtype. METHODS: We screened a Chinese boy with weakness of limbs and his non-consanguineous parents by whole exome sequencing and targeted sequencing. RESULTS: We report a Chinese boy diagnosed with mitochondrial complex III defect type 2 carrying a homozygous variant (c.719-732del, p.Leu240Serfs*17) of the TTC19 gene. According to the genotype analysis of his family members, this is an autosomal recessive inheritance. We provide his clinical manifestation. CONCLUSIONS: A new type of TTC19 mutation (c.719-732del, p.Leu240Serfs*17) was found, which enriched the TTC19 gene mutation spectrum and provided new data for elucidating the pathogenesis of CIII-deficient diseases.

Regulation of BCRP expression and sulfasalazine pharmacokinetics by the nuclear receptor REV-ERBα.

BCRP (breast cancer resistance protein) is a crucial efflux transporter involved in the regulation of the pharmacokinetics and pharmacodynamics of a wide range of drugs. Herein, we aimed to investigate a potential role for the nuclear receptor REV-ERBα in the regulation of BCRP expression and sulfasalazine (a BCRP probe substrate) pharmacokinetics.Regulation of BCRP expression by REV-ERBα was assessed using Rev-erbα-/- mice and AML12 and CT26 cells. Pharmacokinetic analysis was performed with Rev-erbα-/- and wild-type mice after sulfasalazine administration.We found that the expression levels of BCRP mRNA and protein were downregulated in the liver and small intestine of Rev-erbα-dificient mice. In line with this, Rev-erbα ablation increased the systemic exposures of oral sulfasalazine.Positive regulation of BCRP expression and function by REV-ERBα was furtherly confirmed in AML12 and CT26 cells. Moreover, indirect regulation of Bcrp expression by REV-ERBα was potentially mediated by a negative transcription factor DEC2, which is a downstream target of REV-ERBα.In conclusion, REV-ERBα positively regulates BCRP expression in mice, thereby affecting sulfasalazine pharmacokinetics.

Integrated physiological, metabolomic, and proteome analysis of Alpinia officinarum Hance essential oil inhibits the growth of Fusarium oxysporum of Panax notoginseng.

Fusarium oxysporum is the main pathogen of Panax notoginseng root rot, and chemical fungicides remain the primary measures to control the disease. Plant essential oil (EO) is a volatile plant secondary metabolic product that does not produce any residue to replace chemical pesticide. To comprehensively understand the antifungal mechanism of Alpinia officinarum Hance EO, the physiological indicators, proteome and metabolome were analyzed using F. oxysporum spores and hyphae treated with different EO concentrations. The cell membrane was damaged after both low and high concentrations of EO treatment, along with leakage of the cell contents. To resist the destruction of membrane structure, fungi can increase the function of steroid biosynthesis and expression of these catalytic enzymes, including squalene monooxygenase (SQLE), sterol 14alpha-demethylase (CYP51, CYP61A), delta14-sterol reductase (TM7SF2, ERG4), methylsterol monooxygenase (MESO1), and sterol 24-C-methyltransferase (SMT1). Furthermore, the tricarboxylic acid cycle (TCA) was influenced by inhibiting the expression of glutamate synthase (GLT1), 4-aminobutyrate aminotransferase (ABAT), and succinate-semialdehyde dehydrogenase (gabD); increasing malate and gamma-aminobutyric acid (GABA); and decreasing citrate content. The spore germination rate and mycelia growth were decreased because the expression of cohesin complex subunit SA-1/2 (IRR1) and cohesion complex subunit (YCS4, BRN1, YCG1) were inhibited. Particularly, under high EO concentrations, cyclin-dependent kinase (CDC28) and DNA replication licensing factor (MCM) were further inhibited to disrupt the cell cycle and meiosis, thus affecting cell division. The results of this study will enrich the understanding of the antifungal mechanism of EOs and provide an important basis to develop new plant-derived fungicides.

Improved algorithm for expanding the measurement linear range of a four-quadrant detector.

A four-quadrant detector is a kind of photoelectric detector that can quickly and accurately measure the incident angle of light. However, its ability to measure in a large field of view (FOV) is limited by its hardware structure and its calculation principle. To solve these problems, this paper proposes an improved algorithm that can extend the measurement linear range without reducing its measurement accuracy. After that, through simulation and experiment, we compare it with many other location algorithms, including the most widely used classical algorithm and the logarithmic algorithm suitable for large FOVs. Finally, the following conclusions can be drawn from both theoretical data and experimental data: the improved algorithm can significantly improve the measurement accuracy over 50% in the same FOV condition, and the measurable range can be expanded over 25% in the same accuracy requirement. At the same time, the robustness of noise does not decrease; when the root mean square error of the classical algorithm fluctuates at 0.1° in different SNR conditions, the improved algorithm is also 0.1°, while the logarithmic algorithm can reach 1.7°, and other algorithms are around 0.25°. In addition, the improved algorithm is more stable in measuring a certain direction and can effectively avoid the influence from the offset of incident light in another axis.

[Mechanism of Photochemical Degradation of MC-LR by Pyrite].

Pyrite was used as catalyst to degrade Microcystin-LR (MC-LR) at pH 6.8 under visible light irradiation (λ>420 nm). X-ray diffraction (XRD) and scanning electron microscope (SEM) characterization showed that pyrite had the layered structure. The ion state of pyrite before and after the reaction was identified using X-Ray Photoelectron Spectroscopy (XPS), confirming the conversion process of Fe(Ⅱ) to Fe(Ⅲ) on the sulfur defect sites. Electron Spin Resonance (ESR) test showed that pyrite photochemical reaction produced hydroxyl radical (·OH). The results of high performance liquid chromatography (HPLC) and liquid chromatograph-mass spectrometer (LC-MS) showed that visible light irradiation could effectively activate pyrite to degrade MC-LR. The degradation rate of MC-LR reached 100% after 10 hours and the mineralization rate reached 60% after 20 hours. The two reaction pathways of photochemical oxidation of MC-LR by pyrite were discussed.

Knockdown of Dynamitin in testes significantly decreased male fertility in Drosophila melanogaster.

Dynamitin (Dmn) is a major component of dynactin, a multiprotein complex playing important roles in a variety of intracellular motile events. We previously found that Wolbachia bacterial infection resulted in a reduction of Dmn protein. As Wolbachia may modify sperm in male hosts, we speculate that Dmn may have a function in male fertility. Here we used nosGal4 to drive Dmn knock down in testes of Drosophila melanogaster to investigate the functions of Dmn in spermatogenesis. We found that knockdown of Dmn in testes dramatically decreased male fertility, overexpression of Dmn in Wolbachia-infected males significantly rescued male fertility, indicating an important role of Dmn in inducing male fertility defects following Wolbachia infection. Some scattered immature sperm with late canoe-shaped head distributed in the end of Dmn knockdown testis and only about half mature sperm were observed in the Dmn knockdown testis relative to those in the control. Transmission electron microscopy (TEM) exhibited fused spermatids in cysts and abnormal mitochondrial derivatives. Immunofluorescence staining showed significantly less abundance of tubulin around the nucleus of spermatid and scattered F-actin cones to different extents in the individualization complex (IC) during spermiogenesis in Dmn knockdown testes, which may disrupt the nuclear condensation and sperm individualization. Since dynein-dynactin complex has been shown to mediate transport of many cellular components, including mRNAs and organelles, these results suggest that Dmn may play an important role in Drosophila spermiogenesis by affecting transport of many important cytoplasmic materials.

Knockdown of ATPsyn-b caused larval growth defect and male infertility in Drosophila.

The ATPsyn-b encoding for subunit b of ATP synthase in Drosophila melanogaster is proposed to act in ATP synthesis and phagocytosis, and has been identified as one of the sperm proteins in both Drosophila and mammals. At present, its details of functions in animal growth and spermatogenesis have not been reported. In this study, we knocked down ATPsyn-b using Drosophila lines expressing inducible hairpin RNAi constructs and Gal4 drivers. Ubiquitous knockdown of ATPsyn-b resulted in growth defects in larval stage as the larvae did not grow bigger than the size of normal second-instar larvae. Knockdown in testes did not interrupt the developmental excursion to viable adult flies, however, these male adults were sterile. Analyses of testes revealed disrupted nuclear bundles during spermatogenesis and abnormal shaping in spermatid elongation. There were no mature sperm in the seminal vesicle of ATPsyn-b knockdown male testes. These findings suggest us that ATPsyn-b acts in growth and male fertility of Drosophila.

Spatial-resolution analysis and optimal design of integral imaging.

Integral imaging is a promising technology for 3D imaging and display. This paper reports the 3D spatial-resolution research based on reconstructed 3D space. Through geometric analysis of the reconstructed optical distribution from all the element images that attend recording, the relationship among microlens parameters, planar-recording resolution, and 3D spatial resolution was obtained. The effect of microlens parameter accuracy on the reconstructed position error also was discussed. The research was carried on the depth priority integral imaging system (DPII). The results can be used in the optimal design of integral imaging.