Somatic embryogenesis is an example of induced cellular totipotency, where embryos develop from vegetative cells rather than from gamete fusion. Somatic embryogenesis can be induced in vitro by exposing explants to growth regulators and/or stress treatments. The BABY BOOM (BBM) and LEAFY COTYLEDON1 (LEC1) and LEC2 transcription factors are key regulators of plant cell totipotency, as ectopic overexpression of either transcription factor induces somatic embryo formation from Arabidopsis (Arabidopsis thaliana) seedlings without exogenous growth regulators or stress treatments. Although LEC and BBM proteins regulate the same developmental process, it is not known whether they function in the same molecular pathway. We show that BBM transcriptionally regulates LEC1 and LEC2, as well as the two other LAFL genes, FUSCA3 (FUS3) and ABSCISIC ACID INSENSITIVE3 (ABI3). LEC2 and ABI3 quantitatively regulate BBM-mediated somatic embryogenesis, while FUS3 and LEC1 are essential for this process. BBM-mediated somatic embryogenesis is dose and context dependent, and the contextdependent phenotypes are associated with differential LAFL expression. We also uncover functional redundancy for somatic embryogenesis among other Arabidopsis BBM-like proteins and show that one of these proteins, PLETHORA2, also regulates LAFL gene expression. Our data place BBM upstream of other major regulators of plant embryo identity and totipotency.

This review aims to provide comprehensive insights into how to improve the stability of Pt-based catalysts for ORR. First, the basic physical chemistry behind the catalyst degradation, including the fundamental understandings of carbon corrosion, catalyst dissolution, and particle sintering, is highlighted. After a discussion of advanced characterization techniques for the catalyst degradation, the design strategies for improving the stability of Pt-based catalysts are summarized. Finally, further insights into the remaining challenges and future research directions are also provided.

Repetitive transcranial magnetic stimulation (rTMS) acts as a kind of widely-applied and non-invasive method in the intervention of some neurological disorders. This prospective, randomized, double-blind, placebo-controlled trial investigates the effect of rTMS on 30 cases of Alzheimer’s disease (AD) participants, who were classified into mild and moderate groups. Neuropsychological tests were carried out using the AD Assessment Scale-cognitive subscale (ADAS-cog), Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and World Health Organization University of California-Los Angeles, Auditory Verbal Learning Test (WHO-UCLA AVLT) before, immediately after, and 6 weeks after the intervention. In this work, data from 30 AD patients revealed that there was no obvious interaction effect of time-by-group. The ADAS-cog, MMSE and WHO-UCLA AVLT score in the rTMS group was significantly improved compared with baselines at 6 weeks after treatment (all p<0.05). Meanwhile, MoCA scores were also obviously ameliorated in the mild AD patients with rTMS. Besides, subgroup analysis showed that the effect of rTMS on the memory and language of mild AD patients was superior to those of moderate AD patients. In conclusion, our findings suggested that repetitive transcranial magnetic stimulation improves cognitive function, memory and language level of AD patients, especially in the mild stage of AD. Thus, rTMS can be recommended as a promising adjuvant therapy combined with cholinesterase inhibitors at the mild stage of AD patients.

Synthesis of the unconventional phase of noble metal nanocrystals may create new opportunities in exploring intriguing physicochemical properties but remains challenging. In the research field of thin film growth, the interface strain offers a general driving force to stabilize the metastable phase of epitaxial film. Herein we extend this concept to the field of noble metal nanocrystals and report the solution synthesis of metastable face-centered tetragonal Au that has not been discovered before. The successful synthesis relies on the formation of intermetallic AuCu 3 @Au core−shell structure, where the interface strain stabilizes the metastable fct Au overlayer. Compared with the face-centered cubic Au counterpart, the metastable fct Au shows greatly improved catalytic activity toward CO 2 reduction to CO. The density functional theory calculations and spectroscopic studies reveal that the metastable fct Au upshifts the d-band center, which lowers the energy barrier of key intermediate COOH* formation and thus facilitates the reaction kinetics.

The eukaryotic genome is folded into higher-order conformation accompanied with constrained dynamics for coordinated genome functions. However, the molecular machinery underlying these hierarchically organized three-dimensional (3D) chromatin architecture and dynamics remains poorly understood. Here by combining imaging and sequencing, we studied the role of lamin B1 in chromatin architecture and dynamics. We found that lamin B1 depletion leads to detachment of lamina-associated domains (LADs) from the nuclear periphery accompanied with global chromatin redistribution and decompaction. Consequently, the inter-chromosomal as well as inter-compartment interactions are increased, but the structure of topologically associating domains (TADs) is not affected. Using live-cell genomic loci tracking, we further proved that depletion of lamin B1 leads to increased chromatin dynamics, owing to chromatin decompaction and redistribution toward nucleoplasm. Taken together, our data suggest that lamin B1 and chromatin interactions at the nuclear periphery promote LAD maintenance, chromatin compaction, genomic compartmentalization into chromosome territories and A/B compartments and confine chromatin dynamics, supporting their crucial roles in chromatin higher-order structure and chromatin dynamics.

Some microRNAs (miRs) have been demonstrated to play promoting or tumor-suppressing roles in the development and progression of hepatocellular carcinoma (HCC). However, the regulatory mechanism of miR-98-5p in HCC still remains largely unclear. In the present study, our data showed that miR-98-5p was significantly downregulated in 84 cases of HCC tissues compared to the matched adjacent nontumor tissues. In addition, downregulation of miR-98-5p was associated with tumor size, portal vein tumor embolus, node metastasis, and clinical stage in HCC. HCC patients with low expression of miR-98-5p showed a shorter survival time compared with those with high miR-98-5p levels. Moreover, the expression of miR-98-5p was also reduced in HCC cell lines (HepG2, Hep3B, LM3, and SMCC7721) compared to the normal liver cell line THLE-3. Overexpression of miR-98-5p significantly decreased LM3 cell growth by inducing cell cycle arrest at the G1 stage and cell apoptosis. Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) was then identified as a novel target gene of miR-98-5p, and its protein expression was negatively regulated by miR-98-5p in LM3 cells. Overexpression of IGF2BP1 eliminated the effects of miR-98-5p overexpression on the proliferation, cell cycle, and apoptosis of LM3 cells. Finally, we found that IGF2BP1 was upregulated in HCC, and its expression was negatively correlated to miR-98-5p levels. In summary, we demonstrate that miR-98-5p could inhibit HCC cell proliferation while inducing cell apoptosis, partly at least, via inhibition of its target gene IGF2BP1, and we suggest that miR-98-5p may become a promising therapeutic candidate for HCC treatment.

No abstract

Finding an active and robust non-platinum catalyst toward alkaline hydrogen evolution reaction (HER) operating at an ampere-level current density is important for emerging anion exchange membrane (AEM) water electrolysis but...