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Backgrounds C2H2-type zinc finger protein (ZFPs) form a relatively large family of transcriptional regulators in plants, and play many roles in plant growth, development, and stress response. However, the comprehensive analysis of C2H2 ZFPs in cucumber ( CsZFPs ) and their regulation function in cucumber are still lacking. Results In the current study, the whole genome identification and characterization of CsZFPs , including the gene structure, genome localization, phylogenetic relationship, and gene expression were performed. Functional analysis of 4 selected genes by transient transformation were also conducted. A total of 129 full-length CsZFPs were identified, which could be classified into four groups according to the phylogenetic analysis. The 129 CsZFPs unequally distributed on 7 chromosomes. Promoter cis -element analysis showed that the CsZFPs might involve in the regulation of phytohormone and/or abiotic stress response, and 93 CsZFPs were predicted to be targeted by one to 20 miRNAs. Moreover, the subcellular localization analysis indicated that 10 tested CsZFPs located in the nucleus and the transcriptome profiling analysis of CsZFPs demonstrated that these genes are involved in root and floral development, pollination and fruit spine. Furthermore, the transient overexpression of Csa1G085390 and Csa7G071440 into Nicotiana benthamiana plants revealed that they could decrease and induce leave necrosis in response to pathogen attack, respectively, and they could enhance salt and drought stresses through the initial induction of H 2 O 2 . In addition, Csa4G642460 and Csa6G303740 could induce cell death after 5 days transformation. Conclusions The identification and function analysis of CsZFPs demonstrated that some key individual CsZFPs might play essential roles in response to biotic and abiotic stresses. These results could lay the foundation for understanding the role of CsZFPs in cucumber development for future genetic engineering studies.

Alligatorweed [Alternanthera philoxeroides (Mart.) Griseb.] is an invasive semi-aquatic weed that poses serious threats to agricultural production and ecological balance worldwide. However, genetic factors associated with the adaptation and invasion mechanisms of this species are limited. Screening for appropriate reference genes is important for gene expression and functional analysis research in A. philoxeroides. In this study, 30 candidate genes that showed stable expression in different A. philoxeroides tissues under various treatments in RNA-seq data were chosen to design qRT-PCR primers. After the amplification specificity validation, 25 candidates were selected and further evaluated in a diverse set of A. philoxeroides samples, including leaf, stem, and root tissues under drought, salinity, heat, chilling, five kinds of herbicides, and control treatments using qRT-PCR. The delta-CT method, geNorm, NormFinder, BestKeeper, and RefFinder algorithms were used to identify stable reference genes from A. philoxeroides samples. Overall, CoA, RFI2, Tubby, SRP19, and V-ATPase were the top five ideal reference genes in all organs and conditions. Tubby and CoA were the most stable reference genes in the leaf/stem, and RFI2, ERprr, and SPR19 were suitable reference genes for the roots. This work provided a foundation for exploring gene expression profiling of A. philoxeroides, especially those adaptation and invasion-related genes, which may help manage this invasive weed.

Metal‐tolerance proteins (MTPs) are divalent cation transporters and play fundamental roles in plant metal tolerance and ion homeostasis. Despite that, a systematic investigation of MTPs in Cucurbitacea is still lacking. In this study, 142 MTPs were identified from 11 released genomes of 8 Cucurbitaceae species. They were phylogenetically separated into three clusters (Zn‐cation diffusion facilitator proteins [CDFs], Fe/Zn‐CDFs, and Mn‐CDFs) and further subdivided into seven groups (G1, G5, G6, G7, G8, G9, and G12). Characterization analysis revealed that most MTPs were plasma membrane‐located hydrophobic proteins. Motif and exon/intron analysis showed that members in the same group contained similar conserved motifs and gene structures. Moreover, 98 pairs of segmental‐like duplication events were found. The nonsynonymous/synonymous substitution ratios between each pair were less than 1, implying that Cucurbitaceae MTPs were under purification selection. Expression profiling suggested that several MTP genes, such as CsCLMTP1, CmeMTP3, LsMTP3, and Cl97103MTP3, were constitutively expressed in corresponding Cucurbitaceae species, and their expression levels were not significantly altered by NaCl, drought, or pathogen infection. The expression patterns of cucumber MTP genes under Zn2+, Cu2+, Mn2+, and Cd2+ stress were studied by quantitative real‐time polymerase chain reaction and the results showed that these MTPs were induced by at least one metal ion, suggesting their involvement in metal tolerance or transportation. The identification and comprehensive investigation of MTP family members will provide a basis for the analysis of ion transport functions and ion tolerance mechanisms of Cucurbitaceae MTPs.

In cell transplantation therapy, mesenchymal stem cells(MSCs)are ideal seed cells due to their easy acquisition and cultivation, strong regenerative capacity, multi-directional differentiation abilities, and immunomodulatory effects. Autologous MSCs are better applicable compared with allogeneic MSCs in clinical practice. The elderly are the main population for cell transplantation therapy, but as donor aging, MSCs in the tissue show aging-related changes. When the number of generations of in vitro expansion is increased, MSCs will also exhibit replicative senescence. The quantity and quality of MSCs decline during aging, which limits the efficacy of autologous MSCs transplantation therapy. In this review, we examine the changes in MSC senescence as a result of aging, discuss the progress of research on mechanisms and signalling pathways of MSC senescence, and discuss possible rejuvenation strategies of aged MSCs to combat senescence and enhance the health and therapeutic potential of MSCs.

The development of organic thermosensitive fluorophores for use in heatresistant organic light emitting diodes (OLEDs) and large-area and flexible high-temperature sensing remains challenging due to the susceptibility of such materials to thermally facilitated nonradiative decay. A series of "hot exciton" materials ("C1" and "C2") based on pyrrole-substituted triarylphosphine oxides that exhibit high heat resistance have been developed. At a temperature of 260 °C, the films retain 42% (C1) and 29% (C2) of their room temperature fluorescence. This is thanks to thermally facilitated reverse intersystem crossing (RISC) from a high-lying triplet to a singlet state. By combining the novel fluorophores with a yellow emitter with an extremely large Stokes shift, flexible and large-area ratiometric film thermometers are fabricated that demonstrate naked-eye high-temperature sensing. The relative sensitivity, S r , of the film thermometer is higher than 1% K -1 in the high-temperature region (393 to 470 K), with the maximum S r reaching 1.26% K −1 at 430 K. Using these blue emitters, heat-resistant cyan and white OLEDs are also fabricated. With thermally populated singlets and nearly 100% exciton harvesting via fast RISC, the C1-based cyan OLED exhibits a nearly 12-fold enhancement in electroluminescence on heating from room temperature to 530 K, while the corresponding white OLED displays a 5.7-fold electroluminescence enhancement.

Alternanthera philoxeroides is a notorious invasive weed worldwide, but it still lacks a genome information currently. In this study, we collected 4 groups of A. philoxeroides Illumina RNA-seq data (62.5 Gb) and performed a comprehensive de novo assembling. Totally, 421,372 unigenes were obtained with a total length of 230,842,460 bp, with 43,430 (10.31%) unigenes longer than 1000 bp. Then 119,222 (28.3%) unigenes were functional annotated and 235,885 (56.0%) were grouped into reliable lncRNAs reservoir. Besides, 534 tRNA and 234 rRNAs were identified in assembly sequences. Additionally, 131,624 microsatellites were characterized in 106,761 sequences. Then SSR primers were developed for the amplification of 40,752 microsatellites in 36,329 sequences. The miRNAs are key post-transcriptional regulators, about 86 candidate miRNA sequences were detected from A. philoxeroides assembly, and miRNA target genes prediction revealed possible functions of them in growth and development as well as stress responding processes. These results provide a vital basis for sequence-based studies of A. philoxeroides in the future, especially gene function analysis.

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