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Dithiocarbamate has been reported to possess a potent antitumor efficacy against several types of cancer, such as ovarian cancer, breast cancer and hepatocellular carcinoma; however, only a few studies have investigated its inhibitory effect on esophageal cancer. Dipyridylhydrazone dithiocarbamate (DpdtC) is a novel dithiocarbamate derivative that was recently designed, synthesized and evaluated in our previous study. In the present study, the cell growth inhibition and apoptosis induced by DpdtC were measured using the CCK-8 and Annexin V-FITC/propidium iodide staining assays, respectively. Epidermal growth factor receptor (EGFR) signaling pathway and apoptosis related protein levels were examined by western blotting. In vivo effect of DpdtC was evaluated in nude mice bearing KYSE-450 ×enograft tumors. The aims of the present study were to further evaluate the antitumor effects of DpdtC on esophageal cancer cells (KYSE-150 and KYSE-450 cells), and to investigate its potential mechanism of action in vitro and in vivo. It was found that DpdtC significantly inhibited KYSE-150 and KYSE-450 cell proliferation by regulating the EGFR/AKT signaling pathway and inducing apoptosis. In addition, this effect was further identified in vivo; DpdtC inhibited the growth of the KYSE-450 esophageal cancer xenografts by regulating the EGFR/AKT signaling pathway. Furthermore, DpdtC did not affect the body weight in mice. Collectively, the present results suggested that DpdtC may be a promising antitumor drug candidate for the treatment of esophageal cancer.

The compositions and contents of metabolites in the pulp tissue play critical roles in the fruit quality for table grape. In this study, the effects of root restriction (RR) on the primary and secondary metabolites of pulp tissue at five developmental stages were studied at the metabolomics level, using “Red Alexandria” grape berry (Vitis vinifera L.) as materials. The main results were as follows: 283 metabolites were annotated by using ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS); 28 and 16 primary metabolites contents were increased and decreased, and 11 and 19 secondary metabolites contents were increased and decreased, respectively, along the berry development; RR significantly decreased 12 metabolites (four amino acids and derivatives, three organic acids, four flavonoids and one other compound) contents, and improved 40 metabolites (22 amino acids and derivatives, six nucleotides, four carbohydrates, four cofactors, three cinnamic acids and one other compound) accumulation at the different developmental stages. Altogether, our study would be helpful to increase our understanding of grape berry’s responses to RR stress.

To identify the key residues of Thermus thermophilus (T. thermophilus) RTCB in RNA ligation and DNA activation. The biochemical activities of RTCB from T. thermophilus were purified, characterized, and compared. Structure and sequence alignment between T. thermophilus RTCB and Pyrococcus horikoshii (P. horikoshii) RTCB identified six conserved residues (D64, D95, N203, H204, E207, H399) that were essential for RNA ligation. Mutation analysis showed that the expression levels of mutants D95A, N203A, H204A, E207A and H399A were relatively low. Compared to wide-type RTCB, variant D64A protein had no RNA ligation and DNA activation activity. In addition, T. thermophilus RTCB showed acceptable catalytic activity of 3′-phosphate DNA activation at 37 °C. D64 was proved to be essential for RTCB-catalyzed RNA ligation and DNA activation (from 37 to 70 °C) in T. thermophilus.

Pears are one of the most popular nutrient-rich fruits in the world. The pear core and mesocarp have significantly different metabolism, although they display similar profiles. Most strikingly, the core is more acidic in taste. Our results showed that there is more titrated acid but lower total soluble solids in the core compared to the mesocarp, and the content of citric acid was more than 17-fold higher in the core compared to the mesocarp at the ripening stage. Proteomics was used to investigate the difference between core and mesocarp tissues during "Cuiguan" pear ripening. Fifty-four different protein expression patterns were identified in the core and mesocarp. In general, common variably expressed proteins between the core and mesocarp were associated with important physiological processes, such as glycolysis, pyruvate metabolic processes, and oxidative stress. Further, protein level associated qRT-PCR verification revealed a higher abundance of fructose-bisphosphate aldolase and NADP-dependent malic enzymes, which may play a role in the low acid content in the mesocarp, whereas a higher abundance of disulfide isomerase-like 2-2 and calcium-dependent lipid-binding in the core may explain why it is less prone to accumulate sugar. The different levels of a few typical ROS scavenger enzymes suggested that oxidative stress is higher in the core than in the mesocarp. This study provides the first characterization of the pear core proteome and a description of its variation compared to the mesocarp during ripening.

This research aimed to comparatively evaluate the influences of root restriction (RR) cultivation and traditional cultivation (RC) on grape berry skin metabolomics using a non-targeted metabolomics method. Two-hundred-and-ninety-one metabolites were annotated and the kinetics analyses showed that berry skin metabolome is stage- and cultivation-dependent. Our results showed that RR influences significantly the metabolomes of berry skin tissues, particularly on secondary metabolism, and that this effect is more obvious at pre-veraison stage, which was evidenced by the early and fast metabolic shift from primary to secondary metabolism. Altogether, this study provided an insight into metabolic adaptation of berry skin to RR stress and expanded general understanding of berry development.

It remains true that through its signaling mechanisms, Ca2+ also has specific, direct effects on plant metabolic activities, which are poorly understood due to the currently trendy pursuit of Ca2+ signaling studies. This paucity triggered us to examine the virtues of calcium nutrition by investigating carbohydrate metabolism using combinations of physiological and microscopy techniques in Ca2+ sufficient and Ca2+ starved grapevines (Vitis vinifera L.). Net photosynthesis was severely down-regulated in Ca2+ deficient vines, which paralleled with altered chloroplast ultrastructure and reduced chlorophyll concentration. Interestingly, the activities of Rubisco, sucrose phosphate synthase (SPS), sucrose synthase (SS), and fructose-1, 6-bisphosphatase (FBPase) were elevated in Ca2+ deficient vines, while ADP-glucose pyrophosphorylase (AGPase) and phosphoribulose kinase (PRK) activities were reduced. Since plants evolved adaptive mechanisms to cope up with lack or excess of nutrients, these metabolic changes in Ca2+ deficient and sufficient grapevines could be interpreted as acclimation reactions to establish optimal homeostasis. However, given the controversial nature of calcium’s multifunctionality, we need concrete evidence for this radical new paradigm.

The human archease, hereafter named HArch, is identified as a key cofactor of the tRNA-splicing ligase complex, and a potential therapeutic target for treating nervous system injuries. However, little is known about the structural basis of HArch in tRNA maturation, mRNA splicing, and RNA repair. Here we report the crystal structures of HArch and its two mutants D51A and D178A with resolutions ranging from 1.96 Å to 3.4 Å. HArch is composed of an extended N-terminal protrusion domain (NTD) and one compacted C-terminal domain (CTD). Unlike previously reported homologous proteins, the NTD of the first subunit interacts with the CTD of the second one, and this interaction might be important for maintaining protein stability. Moreover, HArch interacts and colocalizes with RNA ligase RTCB in cells. Our current study reveals the atomic structure of HArch and may help us understand its function in mRNA splicing.

ABA plays a crucial role in controlling several ripening-associated processes in grape berries. The soluble proteins named as PYR (pyrabactin resistant)/PYL (PYR-like)/RCAR (regulatory component of ABA receptor) family have been characterized as ABA receptors. Here, the function of a grape PYL1 encoding gene involved in the response to ABA was verified through heterologous expression. The expression level of VlPYL1 was highest in grape leaf and fruit tissues of the cultivar Kyoho, and the expression of VlPYL1 was increased during fruit development and showed a reduction in ripe berries. Over-expression of VlPYL1 enhances ABA sensitivity in Arabidopsis. Using the transient overexpression technique, the VlPYL1 gene was over-expressed in grape berries. Up-regulation of the VlPYL1 gene not only promoted anthocyanin accumulation but also induced a set of ABA-responsive gene transcripts, including ABF2 and BG3. Although tobacco rattle virus (TRV)-induced gene silencing (VIGS) was not successfully applied in the "Kyoho" grape, the application of the transient overexpression technique in grape fruit could be used as a novel tool for studying grape fruit development.

Recent findings have revealed that the protein gasdermin D (GSDMD) plays key roles in cell pyroptosis. GSDMD binds lipids and forms pore structures to induce pyroptosis upon microbial infection and associated danger signals. However, detailed structural information for GSDMD remains unknown. Here, we report the crystal structure of the C-terminal domain of human GSDMD (GSDMD-C) at 2.64-A resolution. The first loop on GSDMD-C inserts into the N-terminal domain (GSDMD-N), which helps stabilize the conformation of the full-length GSDMD. Substitution of this region by a short linker sequence increased levels of cell death. Mutants F283A and F283R can increase protein heterogeneity in vitro and are capable of undergoing cell pyroptosis in 293T cells. The small-angle X-ray–scattering envelope of human GSDMD is consistent with the modeled GSDMD structure and mouse GSDMA3 structure, which suggests that GSDMD adopts an autoinhibited conformation in solution. The positive potential surface of GSDMD-N covered by GSDMD-C is exposed after being released from the autoinhibition state and can form high-order oligomers via a charge–charge interaction. Furthermore, by mapping different regions of GSDMD, we determined that one short segment is sufficient to kill bacteria in vitro and can efficiently inhibit cell growth in Escherichia coli and Mycobacterium Smegmatis. These findings reveal that GSDMD-C acts as an auto-inhibition executor and GSDMD-N could form pore structures via a charge–charge interaction upon cleavage by caspases during cell pyroptosis.