The U-Box E3 Ubiquitin Ligase PUB35 Negatively Regulates ABA Signaling through AFP1-mediated Degradation of ABI5.

Abscisic acid (ABA) signaling is crucial for plant responses to various abiotic stresses. The Arabidopsis (Arabidopsis thaliana) transcription factor ABA INSENSITIVE 5 (ABI5) is a central regulator of ABA signaling. ABI5 BINDING PROTEIN 1 (AFP1) interacts with ABI5 and facilitates its 26S-proteasome-mediated degradation, although the detailed mechanism has remained unclear. Here, we report that an ABA-responsive U-box E3 ubiquitin ligase, PLANT U-BOX 35 (PUB35), physically interacts with AFP1 and ABI5. PUB35 directly ubiquitinated ABI5 in a bacterially reconstituted ubiquitination system and promoted ABI5 protein degradation in vivo. ABI5 degradation was enhanced by AFP1 in response to ABA treatment. Phosphorylation of the T201 and T206 residues in ABI5 disrupted the ABI5-AFP1 interaction and affected the ABI5-PUB35 interaction and PUB35-mediated degradation of ABI5 in vivo. Genetic analysis of seed germination and seedling growth showed that pub35 mutants were hypersensitive to ABA as well as to salinity and osmotic stresses, whereas PUB35 overexpression lines were hyposensitive. Moreover, abi5 was epistatic to pub35, whereas the pub35-2 afp1-1 double mutant showed a similar ABA response to the two single mutants. Together, our results reveal a PUB35-AFP1 module involved in fine-tuning ABA signaling through ubiquitination and 26S-proteasome-mediated degradation of ABI5 during seed germination and seedling growth.

DNA Origami-Based Letterpress Printing of Gold Nanostructures with Predesigned Morphologies.

Creating customizable metallic nanostructures in a simple and controllable manner has been a long-standing goal in nanoscience. In this study, we use DNA origami as a letterpress printing plate and gold nanoparticles as ink to produce predesigned gold nanostructures. The letterpress plate is reusable, enabling the repetitive production of predesigned gold nanostructures. Furthermore, by modifying the DNA origami letterpress plate on magnetic beads, we can simplify the printing processes. We have successfully printed gold nanoparticle dimers, trimers, straight and quadrilateral tetramers, and other nanostructures. Our approach improves the flexibility and stability of metallic nanostructures, simplifying both their design and their operation. It promises universal applicability in the fabrication of metamaterials, biosensors, and surface plasma nanooptics.

The Amplified DNA Logic Gates Based on Aptamer-Receptor Recognition for Cell Detection and Bioimaging.

A powerful and accurate method for identifying and isolating cells would be of great importance due to its sensitivity, gentleness and effectiveness. Here, we designed a receptor-based DNA logic device that allows Boolean logic analysis of multiple cells. For ease of expression, the molecules on the cell surface that can bind to the aptamer are referred to as "receptors". This DNA logic device sends signals based on cell surface sgc8c and sgc4f receptor expression by performing NOT, NOR, AND and OR logic operations, and amplifies and evaluates the signals using HCR. Meanwhile, the release of ICG from the endopore of HMSNs is controlled by affecting structural changes in the DNA logic device. This approach can accurately identify and treat multiple cells on demand based on the presence or absence of cell-specific receptors, facilitating the development of personalized medicine.

Construction of nanocarriers based on nucleic acids and their applications in nanobiology delivery systems.

In recent years, nanocarriers based on nucleic acids have emerged as powerful and novel nanocarriers that are able to meet the demand for cancer-cell-specific targeting. Functional dynamics analysis revealed good biocompatibility, low toxicity and programmable structures, and their advantages include controllable size and modifiability. The development of novel hybrids has focused on the distinct roles of biosensing, drug and gene delivery, vaccine transport, photosensitization, counteracting drug resistance and functioning as carriers and logic gates. This review is divided into three parts: (i) DNA nanocarriers, (ii) RNA nanocarriers and (iii) DNA/RNA hybrid nanocarriers and their applications in nanobiology delivery systems. We also provide perspectives on possible future directions for growth in this field.

Effects of chitooligosaccharide-zinc on the ovarian function of mice with premature ovarian failure via the SESN2/NRF2 signaling pathway.

Chitooligosaccharide-zinc (COS·Zn) is a powerful anti-oxidant and anti-aging scavenger, whose anti-oxidative ability immensely exceeds vitamin C. Therefore, this study was aimed to investigate the protective effects of COS·Zn against premature ovarian failure (POF) and potential mechanisms. Female KM adult mice were divided into the following groups: a treatment group (150 mg·kg-1·d-1 COS·Zn), a treatment group (300 mg·kg-1·d-1 COS·Zn), a prevention group, two control groups and two CY/BUS groups. COS·Zn (150, 300 mg·kg-1·d-1) and COS·Zn (300 mg·kg-1·d-1) were therapeutically and preventatively administered to POF mice in the treatment and prevention studies, respectively. All the groups were administered for 21 days. Fewer primary and secondary follicles were observed in the COS·Zn-treated groups (including the treatment and prevention groups) than those of the control groups. Meanwhile, the ovarian index and the levels of FSH and LH notably increased in the treatment and prevention groups compared with those in the CY/BUS group. The levels of MVH, OCT4 and PCNA in the treatment group (300·kg-1·d-1 COS·Zn) and MVH in the prevention group remarkably increased compared with those in the CY/BUS groups. Meanwhile, the levels of P53 and P16 protein were down-regulated in the treatment and prevention groups compared with those in the CY/BUS groups. Additionally, the amounts of Sestrin2 (SESN2) and SOD2 protein were obviously higher in the treatment group (150 mg·kg-1·d-1 COS·Zn) than those in the CY/BUS groups. Similarly, the amounts of NRF2 and SESN2 protein were up-regulated in the prevention group. Besides, an increased GSH level was observed in the two treatment groups, compared with that in the CY/BUS groups, and the same trend was also present in the prevention group. Taken together, COS·Zn improves the ovarian and follicular development through regulating the SESN2/NRF2 signaling pathway. These results suggest the role of COS·Zn as a novel agent for the treatment and prevention of POF.

Au-Fe3O4 nanoagent coated cell membrane for targeted delivery and enhanced chem/photo therapy.

Here, we propose a cancer cell membrane (CM) coated Au-Fe3O4 complex (AFTP@CM), loaded with tannic acid and phorbol 12-myristate 13-acetate for targeted drug delivery and enhanced chem/photo therapy.

Lysosomal escaped protein nanocarriers for nuclear-targeted siRNA delivery.

In the process of drug carrier design, lysosome degradation in cells is often neglected, which makes a considerable number of drugs not play a role. Here, we have constructed a tumor treatment platform (Apn/siRNA/NLS/HA/Apt) with unique lysosomal escape function and excellent cancer treatment effect. Apoferritin (Apn) has attracted more and more attention because of its high uniformity, modifiability, and controllability. Meanwhile, its endogenous nature can avoid the risk of immune response being eliminated. We used aptamer modified iron deficient protein nanocages (Apn) to tightly encapsulate the combination of siRNA and NLS (siRNA/NLS) with influenza virus hemagglutinin (HA peptide). After Apn/siRNA/NLS/HA/Apt was targeted into cells, the acidic environment of lysosome led to the cleavage of Apn nanocages, and the release of siRNA/NLS and HA peptide. HA peptide can destroy lysosome membrane, make siRNA/NLS escape lysosome, and enter the nucleus under the action of NLS, resulting in efficient gene silencing effect. This kind of cancer treatment strategy based on Apn nanocage shows high biocompatibility and unique lysosome escape property, which significantly improves the drug delivery and treatment efficiency. Lysosomal escape protein nanocarriers for nuclear-targeted siRNA delivery.

Self-assembled peptide nanoparticles with endosome escaping permits for co-drug delivery.

The diagnosis and treatment of major diseases, especially tumors, was the key to improving the cure rate and survival rate of patients. Therefore, one of the main goals of modern medicine was to develop effective, non-toxic treatments. This paper successfully established dipeptide nanoparticles/clofarabine/aptamer AS1411/influenza hemagglutinin peptide/siRNA/doxorubicin (DNPs/Clolar/AS1411/HA/RNA/DOX) multi-functional nanoparticles for specific delivery, cancer treatment and bioimaging. It was an ideal choice for multi-drug synergy treatment. First, non-toxic DNPs formed by self-assembly of dipeptides with safe and biocompatible effect. Second, from the perspective of the multi-functional nanoparticles for nano-drug tumors imaging monitoring, AS1411 and HA were used as cell permits for enhancing the specificity of cell drug delivery ability and improving the endosomal escape, respectively. Third, the multi-functional nanoparticles with Clolar, siRNA and DOX, three drug synergistic treatments were used to improve the therapeutic effect of tumors. Both cell experiments and vivo experiments demonstrated that the synergistic treatment of the multi-drugs was superior to the effect of single-drug therapy. Thus, the proposed multi-functional nanoparticles have initiated new ideas for these hybrid anticancer drugs based on peptide self-assembled nanocarriers and its widely applications in biomedicine.

An aggregation-induced emission fluorogen/DNA probe carrying an endosome escaping pass for tracking reduced thiol compounds in cells.

The fluorescent nanoprobes for reduced thiol compounds (represented by glutathione, GSH) are constructed based on the aggregation-induced emission (AIE) luminescence mechanism and endosome escape technology. First, a DNA sequence was designed with the decoration of biotin at the 5'-end, disulfide bound in the internal portion, and amino at the 3'-end. The aptamer of the MCF-7 cell was also one of the most important structures in our DNA sequence for the selectivity of MCF-7 cells. We modified streptavidin-modified magnetic beads (MB) with biotin-modified influenza virus hemagglutinin peptide (HA) and biotin-DNA-amino to form MB/DNA/HA. Carboxyl-modified tetraphenylethylene (TPE), an iconic AIE fluorogen, was bonded with amino-modified DNA by covalent interactions (TPE/DNA). Then, the TPE molecule was attached on the outer layer of MB via biotin-modified TPE/DNA to form MB/DNA/HA/TPE. Compared with traditional AIE/biomolecule conjugates, the nanoprobe had an enhanced endosome escape function, due to the assembly of HA. This construction made the intracellular fluorescence response more accurate. In the presence of reduced thiol compounds (take GSH, for example), the disulfide bond on the DNA was reduced by thiol-disulfide exchange reactions and the TPE molecule was released into the solution. The shedding TPE molecule was more hydrophobic than TPE/DNA and the conversion of TPE/DNA to shedding TPE could lead to the aggregation of the TPE fluorogen. Thus, its fluorescence was enhanced. Under the optimized condition, the fluorescence intensity increased with the increase in concentration of GSH' ranging from 1.0 × 10-9 M to 1.0 × 10-5 M' and the detection limit was 1.0 × 10-9 M. The relative standard deviation (RSD) was calculated to be 3.6%. The recovery in cell homogenate was from 94.5 to 102.7%. The nanoprobe provided a way for the detection of reduced thiol compounds in MCF-7 cells. We envision that, in the near future, our strategy of DNA-instructed AIE could be widely applied for biosensing and bioimaging in vitro and even in vivo with dramatically enhanced sensitivity. Graphical Abstract.

Controlling chronic low-grade inflammation to improve follicle development and survival.

Chronic low-grade inflammation is one cause of follicle development disturbance. Chronic inflammation exists in pathological conditions such as premature ovarian failure, physiological aging of the ovaries, and polycystic ovary syndrome. Inflammation of the whole body can affect oocytes via the follicle microenvironment, oxidative stress, and GM-CSF. Many substances without toxic side-effects extracted from natural organisms have gradually gained researchers' attention. Recently, chitosan oligosaccharide, resveratrol, anthocyanin, and melatonin have been found to contribute to an improvement in inflammation. This review discusses the interrelationships between chronic low-grade inflammation and follicle development, the underlying mechanisms, and methods that may improve follicle development by controlling the level of chronic low-grade inflammation.

Activated Plasmonic Nanoaggregates for Dark-Field in Situ Imaging for HER2 Protein Imaging on Cell Surfaces.

Dark-field microscopy (DFM) based on localized surface plasmon resonance (LSPR) was used for observation of experimental phenomena, which is a hopeful nondamaging and non-photobleaching biological imaging technique. In this strategy, plasma nanoaggregates with stronger scattering efficiency were formed in the presence of the target, causing a "turn-on" phenomenon, when asymmetry modified AuNPs were introduced as probes with zero LSPR background. First, Au1-N3 probe and Au2-C≡C probe were designed for the cycloaddition between azide and alkyne to form AuNP dimers under catalytic action by Cu+, which was obtained from the reduction of Cu2+ by sodium ascorbate. The two kinds of probes were successfully used for the detection of Cu2+ in rat serum. Then, to apply this concept to protein on cells, DNA and antibody were modified on the probes. DNA1/Au1-N3 probe and anti-HER2/Au2-C≡C probe were proposed for HER2 protein DFM on cells. By designing an aptamer sequence in primer, the rolling circle amplification (RCA) was introduced in HER2 DFM on cells, and the image signal was much brighter than that from no-RCA. The unique design made it easier to discriminate the target signal from background noise in cell DFM. This method might be used in the fields of molecular diagnostics and cell imaging.

[Expression relationship of Hippo signaling molecules and ovarian germline stem cell markers in the ovarian aging process of women and mice].

The present study was aimed to investigate the expression relationship of Hippo signaling molecules and ovarian germline stem cell (OGSC) markers in the development schedule of OGSCs during ovarian aging in women and mice. The ovaries of 2-month-old mature (normal control) and 12-month-old (physiological ovarian aging) KM mice were sampled, and the ovarian cortex samples of young (postpuberty to 35 years old), middle age (36-50 years old) and menopausal period (51-60 years old) women were obtained with consent. The mice model of pathological ovarian aging was established by intraperitoneal injection of cyclophosphamide/busulfan (CY/BUS). HE staining was used to detect the changes of follicles at different stages, and the localization and expression changes of Hippo signaling molecules and OGSCs related factors (MVH/OCT4) were detected by immunohistochemistry and immunofluorescence staining. Western blot was used to detect the protein expression levels of the major molecules in the Hippo signaling pathway and OGSCs related factors. The results showed that there were not any normal follicles, but a few atresia follicles in the ovaries from physiological and pathological ovarian aging mice. Compared with the normal control mice, both the physiological and pathological ovarian aging mice showed decreased protein expression levels of the main Hippo signaling molecules (pYAP1) and MVH/OCT4; Whereas only the pathological ovarian aging mice showed increased ratio of pYAP1/YAP1. In comparison with the young women, the middle age and menopausal women showed looser structure of ovarian surface epithelium (OSE) and less ovarian cortical cells. The protein expression level of LATS2 in the OSE was the highest in young women, MST1 expression was the lowest in the menopausal period women, and the expression levels of YAP1 and pYAP1 were the highest in middle age women. Compared with the young women, the middle age and menopausal period women exhibited significantly decreased ratio of OSE pYAP1/YAP1, whereas there was no significant difference between them. The expression level of MVH protein in OSE from the young women was significantly higher than those of the middle age and menopausal period women. These results indicate that there is an expression relationship between the main molecules of Hippo signaling pathway and OGSCs related factors, which suggests that Hippo signaling pathway may regulate the expression levels of OGSCs related factors, thus participating in the process of physiological and pathological degeneration of ovarian.

Butyrolactone and cycloheptanetrione from mangrove-associated fungus Aspergillus terreus.

A new butyrolactone, 7″-hydroxybutyrolactone III (1) and three new cycloheptanetriones, terretrione A-C (2-4), together with five known compounds, butyrolactone I, cyclo(Leu-Pro), cyclo(Val-Pro), cyclo(Ile-Pro), cyclo(Phe-Pro), were isolated from mangrove-associated marine fungus Aspergillus terreus. The structures of these compounds were elucidated on the basis of physical data analysis (NMR, high resolution-electrospray ionization (HR-ESI)-MS), especially by 2D-NMR techniques. These compounds showed weak cytotoxicity in vitro against HCT-8, Bel-7402, BGC-823, A2780 cell lines.