Tissue equivalent conversion of silicon-based microdosemeters in hadron therapy.

Silicon has been developed as a microdosemeter, as it can provide sensitive volumes at submicrometric levels, does not need a gas supply, has a fast response, and has low power consumption. However, since the energy response in silicon is not the same as that in tissue, a spectral conversion from silicon to tissue is necessary to obtain the probability distribution of energy deposition in tissue. In this work, we present a method for microdosimetric spectra conversion from silicon to tissue based on the scaled Fourier transformation and the geometric scaling factor, which shows relatively good results in the spectral conversion from diamond to tissue. The results illustrate that the method can convert the energy deposition spectra from silicon to tissue with proper accuracy. Meanwhile, the inconsistency between the converted and actual spectra due to the inherent difference was also observed. Whereas, the reasons for the disagreement are different. For the plateau part of the Bragg curve, the discrepancy between the converted and actual spectra is due to the poor tissue equivalent of silicon. For the proximal part of the Bragg curve, the spectral difference is attributed to the different shapes of the energy deposition spectra obtained in silicon and water, which is the same as that in the diamond. In summary, this method can be employed in the tissue equivalent conversion of silicon microdosemeter, but the poor tissue equivalent of silicon limited the accuracy of this method. In addition, the correction for the deviation between the converted and calculated spectra due to the difference in spectral shapes is required to improve the practicality of this mod.

Dimethoxytolyl propylresorcinol induces apoptosis and mitophagy in human leukemia cells through the PI3K/AKT pathway.

Dimethoxytolyl propylresorcinol (UP302), a natural compound extracted from Dianella ensifolia, owing to its tyrosinase inhibitory and strong antioxidant properties, is used in whitening cosmetics. However, the role of UP302 has not been reported in cancer treatment. This study aimed to assess the in vitro antitumor activity of UP302 in different tumor cells. It inhibited the growth of certain cancer cell lines and especially in leukemia cells. Therefore, we investigated the antitumor effect of UP302 in leukemia by examining the cell cycle, apoptosis, reactive oxygen species levels (ROS) production, and changes in mitochondrial membrane potential. Our results demonstrated that UP302 inhibited the growth of leukemia cells both in vivo and in vitro and exerted a proapoptotic effect on MV411 and K562 cells, confirmed by flow cytometry and western blot analysis. Furthermore, UP302 promoted autophagy in MV411 and K562 cells. Transmission electron microscopy and western blot analysis showed that UP302 induced mitophagy in MV411 and K562 cells. In addition, the autophagy inhibitor chloroquine could enhance UP302-induced apoptosis, suggesting that UP302-mediated autophagy may be protective in MV411 and K562 cells. In conclusion, our study is the first to provide evidence for the anti-leukemia properties of UP302 and the potential clinical use of UP302 combined with autophagy inhibitors as a chemotherapeutic strategy for human leukemia.

Overexpression of Myrothamnus flabellifolia MfWRKY41 confers drought and salinity tolerance by enhancing root system and antioxidation ability in Arabidopsis.

Myrothamnus flabellifolia is the only woody resurrection plant discovered so far and could recover from extreme desiccation condition. However, few genes related to its strong drought tolerance have been characterized, and the underlying molecular mechanisms remains mysterious. Members of WRKY transcription factor family are effective in regulating abiotic stress responses or tolerance in various plants. An early dehydration-induced gene encoding a WRKY transcription factor namely MfWRKY41 was isolated from M. flabellifolia, which is homologous to AtWRKY41 of Arabidopsis. It contains a typical WRKY domain and zinc finger motif, and is located in the nucleus. Comparing to wild type, the four transgenic lines overexpressing MfWRKY41 showed better growth performance under drought and salt treatments, and exhibited higher chlorophyll content, lower water loss rate and stomatal aperture and better osmotic adjustment capacity. These results indicated that MfWRKY41 of M. flabellifolia positively regulates drought as well as salinity responses. Interestingly, the root system architecture, including lateral root number and primary root length, of the transgenic lines was enhanced by MfWRKY41 under both normal and stressful conditions, and the antioxidation ability was also significantly improved. Therefore, MfWRKY41 may have potential application values in genetic improvement of plant tolerance to drought and salinity stresses. The molecular mechanism involving in the regulatory roles of MfWRKY41 is worthy being explored in the future.

Transcriptome Analysis of Moso Bamboo (Phyllostachys edulis) Reveals Candidate Genes Involved in Response to Dehydration and Cold Stresses.

Bamboo (Bambusoideae) belongs to the grass family (Poaceae) and has been utilized as one of the most important nontimber forest resources in the world. Moso bamboo (Phyllostachys edulis) is a large woody bamboo with high ecological and economic values. Global climate change brings potential challenges to the normal growth of moso bamboo, and hence its production. Despite the release of moso bamboo genome sequence, the knowledge on genome-wide responses to abiotic stress is still limited. In this study, we generated a transcriptome data set with respect to dehydration and cold responses of moso bamboo using RNA-seq technology. The differentially expressed genes (DEGs) under treatments of dehydration and cold stresses were identified. By combining comprehensive gene ontology (GO) analysis, time-series analysis, and co-expression analysis, candidate genes involved in dehydration and cold responses were identified, which encode abscisic acid (ABA)/water deficit stress (WDS)-induced protein, late embryogenesis abundant (LEA) protein, 9-cis-epoxycarotenoid dioxygenase (NCED), anti-oxidation enzymes, transcription factors, etc. Additionally, we used PeLEA14, a dehydration-induced gene encoding an "atypical" LEA protein, as an example to validate the function of the identified stress-related gene in tolerance to abiotic stresses, such as drought and salt. In this study, we provided a valuable genomic resource for future excavation of key genes involved in abiotic stress responses and genetic improvement of moso bamboo to meet the requirement for environmental resilience and sustainable production.

Editing of the starch synthase IIa gene led to transcriptomic and metabolomic changes and high amylose starch in barley.

In this study, a range of barley allelic mutants lost ADPG binding structure of starch synthase IIa (SSIIa) were created through targeted mutagenesis of SSIIa by RNA-guided Cas9. The transcriptomic and qRT-PCR results showed the increased mRNA expression of HvGBSSI and the decreased HvSSIIa and HvSBEI levels in ssIIa mutant grains, which were consistent with the expressions of GBSSI, SSS and SBE enzymatic activities, respectively. However, the increased expressions of HvSSI cannot effectively compensate for the loss of HvSSIIa. The metabolic pathway analysis showed that the mutation of SSIIa led to increased ADP-glucose synthesis in barley grains. The ssIIa mutant grains had two and six times amylose, and RS contents in control grains, respectively, and significantly changed starch structure and functions compared to the controls. No metabolite changes could compensate for the decrease of starch biosynthesis in the ssIIa null mutant.

Genome-wide identification of bZIP transcription factor genes related to starch synthesis in barley (Hordeum vulgare L.).

The basic leucine zipper (bZIP) family of genes encode transcription factors that play key roles in plant growth and development. In this study, a total of 92 HvbZIP genes were identified and compared with previous studies using recently released barley genome data. Two novel genes were characterized in this study, and some misannotated and duplicated genes from previous studies have been corrected. Phylogenetic analysis results showed that 92 HvbZIP genes were classified into 10 groups and three unknown groups. The gene structure and motif distribution of the three unknown groups implied that the genes of the three groups may be functionally different. Expression profiling indicated that the HvbZIP genes exhibited different patterns of spatial and temporal expression. Using qRT-PCR, more than 10 HvbZIP genes were identified with expression patterns similar to those of starch synthase genes in barley. Yeast one-hybrid analysis revealed that two of the HvbZIP genes exhibited in vitro binding activity to the promoter of HvAGP-S. The two HvbZIP genes may be candidate genes for further study to explore the mechanism by which they regulate the synthesis of barley starch.

Study of particle transport and gas amplification mechanism in proportional counters.

Gas amplification is an essential feature of the proportional counter. The Boltzmann equation and the Townsend ionization coefficient are introduced to describe the behavior of electrons and the gas amplification in proportional counters, respectively. However, it is difficult to solve the Boltzmann equation completely and to obtain the critical radius at which electron avalanche begins. Therefore, we try to employ the Continuity equation and the linear stopping power to derive the distribution of particles and the critical radius. The space charge effect was also investigated to understand its influence on the gas amplification of the proportional counter. Finally, the gas amplification was calculated based on the classical theory of electron transport. The results indicate that the theoretical value is in good agreement with the experimental data. This means that the continuity equation and the linear stopping power can be used to depict the particle transport and gas amplification mechanism in proportional counters.

Genome-wide transcriptome profiling indicates the putative mechanism underlying enhanced grain size in a wheat mutant.

Grain size is an important trait for crops. The endogenous hormones brassinosteroids (BRs) play key roles in grain size and mass. In this study, we identified an ethyl methylsulfonate (EMS) mutant wheat line, SM482gs, with increased grain size, 1000-grain weight, and protein content, but decreased starch content, compared with the levels in the wild type (WT). Comparative transcriptomic analysis of SM482gs and WT at four developmental stages [9, 15, 20, and 25 days post-anthesis (DPA)] revealed a total of 264, 267, 771, and 1038 differentially expressed genes (DEGs) at these stages. Kyoto Encyclopedia of Genes and Genomes (KEGG) database analysis showed that some DEGs from the comparison at 15 DPA were involved in the pathway of "brassinosteroid biosynthesis," and eight genes involved in BR biosynthesis and signal transduction were significantly upregulated in SM482gs during at least one stage. This indicated that the enhanced BR signaling in SM482gs might have contributed to its increased grain size via network interactions. The expression of seed storage protein (SSP)-encoding genes in SM482gs was upregulated, mostly at 15 and 20 DPA, while most of the starch synthetase genes showed lower expression in SM482gs at all stages, compared with that in WT. The expression patterns of starch synthase genes and seed storage protein-encoding genes paralleled the decreased level of starch and increased storage protein content of SM482gs, which might be related to the increased seed weight and wrinkled phenotype. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-020-02579-6.

Mutation of the d-hordein gene by RNA-guided Cas9 targeted editing reducing the grain size and changing grain compositions in barley.

In this study, we successfully knock-out the d-hordein component of barley storage protein using RNA-guided Cas9. Mutation frequencies of 25% and 14% at two different target sites were obtained. Homozygous mutant plants that were T-DNA free were identified in the T1 generation. Barley grains without d-hordein proteins from T2 seeds showed a significantly reduced grain size compared to the parent plant and control non-edited line. The protein matrix surrounding the starch granules was increased, whereas the starch granules themselves were decreased in size in the mutant plants compared to controls. The main effect of a lack of d-hordein was a considerable decrease in the prolamines and an increase in the glutenins. The changes of other grain composition included the increased starch content, amylose content, and ß-glucan content. The roles of d-hordein mutation on barley grain size and grain composition remain to be studied.

The production of wheat - Aegilops sharonensis 1Ssh chromosome substitution lines harboring alien novel high-molecular-weight glutenin subunits.

In our previous work, a novel high-molecular-weight glutenin subunit (HMW-GS) with an extremely large molecular weight from Aegilops sharonensis was identified that may contribute to excellent wheat (Triticum aestivum) processing quality and increased dough strength, and we further generated HMW-GS homozygous lines by crossing. In this study, we crossed the HMW-GS homozygous line 66-17-52 with 'Chinese Spring' Ph1 mutant CS ph1b to induce chromosome recombination between wheat and Ae. sharonensis. SDS-PAGE was used to identify 19 derived F2 lines with the HMW-GSs of Ae sharonensis. The results of non-denaturing fluorescence in situ hybridization (ND-FISH) indicated that lines 6-1 and 6-7 possessed a substitution of both 5D chromosomes by a pair of 1Ssh chromosomes. Further verification by newly developed 1Ssh-specific chromosome markers showed that these two lines amplified the expected fragment. Thus, it was concluded that lines 6-1 and 6-7 are 1Ssh(5D) chromosome substitution lines. The 1Ssh(5D) chromosome substitution lines, possessing alien subunits with satisfactory quality-associated structural features of large repetitive domains and increased number of subunits, may have great potential in strengthening the viscosity and elasticity of dough made from wheat flour. Therefore, these substitution lines can be used for wheat quality improvement and further production of 1Ssh translocation lines.

Alternative splicing results in a lack of starch synthase IIa-D in Chinese wheat landrace.

We evaluated the SGP-1 protein composition of 368 Chinese wheat landraces using SDS-PAGE. The SGP-D1 null type was identified in three accessions (Xiaoqingmang, Pushanbamai, and P119). An 18-bp deletion and 9-bp variation were found at the junction region of the 7th intron and 8th exon, leading to deletion of the intron-exon junction recognition site AG when aligned the 8261-bp DNA sequence of TaSSIIa-D in Pushanbamai with that of Chinese Spring. Four cDNA types with mis-spliced isoforms were subsequently detected through amplification of TaSSIIa-D cDNAs. Among these, nine type II cDNAs with a 16-bp deletion in the 8th exon were detected, indicating that the major transcriptional pattern of TaSSIIa in Pushanbamai is type II. In the type IV cDNA, a 97-bp sequence remains undeleted in the end of the 5th exon. The amylose content in Pushanbamai was significantly higher than that in all control lines under field conditions, which suggested that deletion of SGP-D1 has an efficient impact on amylose content. As the TaSSIIa gene plays an important role in regulating the content of amylose, it is anticipated that these natural variants of TaSSIIa-D will provide useful resources for quality improvement in wheat.

Acceleration of electroactive anammox (electroammox) start-up by switching acetate pre-acclimated biofilms to electroammox biofilms.

In this study, an operational method of switching acetate media to ammonium media after the formation of stable acetate-oxidizing biofilms (ACAM mode), was developed. The results showed that the start-up time was shortened to 48days in the ACAM mode compared to the AM (always ammonium media) mode (>120days), and an ammonia removal rate of 82±3% was achieved successfully and sustainably in the ACAM mode during the following long-term operation of more than 2months. Moreover, the ACAM mode was more efficient in enriching both electroammox bacteria and electricigens with Ignavibacteriaceae, Geobacteraceae and Nitrosomonadaceae as dominant families, which could favour the formation of high-performance electroammox biofilms. Thus, the ACAM mode might promote the widespread implementation of the electroammox process.

Genome-Wide Identification, Characterization, and Stress-Responsive Expression Profiling of Genes Encoding LEA (Late Embryogenesis Abundant) Proteins in Moso Bamboo (Phyllostachys edulis).

Late embryogenesis abundant (LEA) proteins have been identified in a wide range of organisms and are believed to play a role in the adaptation of plants to stress conditions. In this study, we performed genome-wide identification of LEA proteins and their coding genes in Moso bamboo (Phyllostachys edulis) of Poaceae. A total of 23 genes encoding LEA proteins (PeLEAs) were found in P. edulis that could be classified to six groups based on Pfam protein family and homologous analysis. Further in silico analyses of the structures, gene amount, and biochemical characteristics were conducted and compared with those of O. sativa (OsLEAs), B. distachyon (BdLEAs), Z. mays (ZmLEAs), S. bicolor (SbLEAs), Arabidopsis, and Populus trichocarpa. The less number of PeLEAs was found. Evolutionary analysis revealed orthologous relationship and colinearity between P. edulis, O. sativa, B. distachyon, Z. mays, and S. bicolor. Analyses of the non-synonymous (Ka) and synonymous (Ks)substitution rates and their ratios indicated that the duplication of PeLEAs may have occurred around 18.8 million years ago (MYA), and divergence time of LEA family among the P. edulis-O. sativa and P. edulis-B. distachyon, P. edulis-S. bicolor, and P. edulis-Z. mays was approximately 30 MYA, 36 MYA, 48 MYA, and 53 MYA, respectively. Almost all PeLEAs contain ABA- and (or) stress-responsive regulatory elements. Further RNA-seq analysis revealed approximately 78% of PeLEAs could be up-regulated by dehydration and cold stresses. The present study makes insights into the LEA family in P. edulis and provides inventory of stress-responsive genes for further functional validation and transgenic research aiming to plant genetic improvement of abiotic stress tolerance.

Genome-wide identification and characterization of TIFY family genes in Moso Bamboo (Phyllostachys edulis) and expression profiling analysis under dehydration and cold stresses.

The proteins containing the TIFY domain belong to a plant-specific family of putative transcription factors and could be divided into four subfamilies: ZML, TIFY, PPD and JAZ. They not only function as key regulators of jasmonate hormonal response, but are also involved in responding to abiotic stress. In this study, we identified 24 TIFY genes (PeTIFYs) in Moso bamboo (Phyllostachys edulis) of Poaceae by analyzing the whole genome sequence. One PeTIFY belongs to TIFY subfamily, 18 and five belong to JAZ and ZML subfamilies, respectively. Two equivocal gene models were re-predicted and a putative retrotransposition event was found in a ZML protein. The distribution and conservation of domain or motif, and gene structure were also analyzed. Phylogenetic analysis with TIFY proteins of Arabidopsis and Oryza sativa indicated that JAZ subfamily could be further divided to four groups. Evolutionary analysis revealed intragenomic duplication and orthologous relationship between P. edulis, O. sativa, and B. distachyon. Calculation of the non-synonymous (Ka) and synonymous (Ks) substitution rates and their ratios indicated that the duplication of PeTIFY may have occurred around 16.7 million years ago (MYA), the divergence time of TIFY family among the P. edulis-O. sativa, P. edulis-B. distachyon, and O. sativa-B. distachyon was approximately 39 MYA, 39 MYA, and 45 MYA, respectively. They appear to have undergone extensive purifying selection during evolution. Transcriptome sequencing revealed that more than 50% of PeTIFY genes could be up-regulated by cold and dehydration stresses, and some PeTIFYs also share homology to know TIFYs involved in abiotic stress tolerance. Our results made insights into TIFY family of Moso bamboo, an economically important non-timber forest resource, and provided candidates for further identification of genes involved in regulating responses to abiotic stress.

Molecular cloning and characterization of a novel freezing-inducible DREB1/CBF transcription factor gene in boreal plant Iceland poppy (Papaver nudicaule).

DREB1 of the AP2/ERF superfamily plays a key role in the regulation of plant response to low temperatures. In this study, a novel DREB1/CBF transcription factor, PnDREB1, was isolated from Iceland poppy (Papaver nudicaule), a plant adaptive to low temperature environments. It is homologous to the known DREB1s of Arabidopsis and other plant species. It also shares similar 3D structure, and conserved and functionally important motifs with DREB1s of Arabidopsis. The phylogenetic analysis indicated that the AP2 domain of PnDREB1 is similar to those of Glycine max, Medicago truncatula, and M. sativa. PnDREB1 is constitutively expressed in diverse tissues and is increased in roots. qPCR analyses indicated that PnDREB1 is significantly induced by freezing treatment as well as by abscissic acid. The expression levels induced by freezing treatment were higher in the variety with higher degree of freezing tolerance. These results suggested that PnDREB1 is a novel and functional DREB1 transcription factor involved in freezing response and possibly in other abiotic stresses. Furthermore, the freezing-induction could be suppressed by exogenous gibberellins acid, indicating that PnDREB1 might play some role in the GA signaling transduction pathway. This study provides a basis for better understanding the roles of DREB1 in adaption of Iceland poppy to low temperatures.

Osteopontin-induced brown adipogenesis from white preadipocytes through a PI3K-AKT dependent signaling.

Recent studies have shown that OPN (osteopontin) plays critical roles in cell survival, differentiation, bio-mineralization, cancer and cardiovascular remodeling. However, its roles in the differentiation of brown adipocytes and the underlying mechanisms remain unclear. Therefore, the aim of this study was to investigate the roles of OPN in the brown adipogenesis and the underlying mechanisms. It was shown that the OPN successfully induced the differentiation of 3T3-L1 white preadipocytes into the PRDM16(+) (PRD1-BF1-RIZ1 homologous domain containing 16) and UCP-1(+) (uncoupling protein-1) brown adipocytes in a concentration and time-dependent manner. Also, activation of PI3K (phosphatidylinositol 3-kinase)-AKT pathway was required for the OPN-induced brown adipogenesis. The findings suggest OPN plays an important role in promoting the differentiation of the brown adipocytes and might provide a potential novel therapeutic approach for the treatment of obesity and related disorders.

Pharmacological activation of PPAR gamma ameliorates vascular endothelial insulin resistance via a non-canonical PPAR gamma-dependent nuclear factor-kappa B trans-repression pathway.

Vascular endothelial insulin resistance (IR) is a critically initial factor in cardiocerebrovascular events resulted from diabetes and is becoming a worldwide public health issue. Thiazolidinediones (TZDs) are clinical insulin-sensitizers acting through a canonical peroxisome proliferator-activated receptor gamma (PPARγ)-dependent insulin trans-activation pathway. However, it remains elusive whether there are other mechanisms. In current study, we investigated whether TZDs improve endothelial IR induced by high glucose concentration or hyperglycemia via a non-canonical PPARγ-dependent nuclear factor-kappa B (NF-κB) trans-repression pathway. Our results showed that pre-treatment with TZDs dramatically decrease the susceptibility of endothelial cell to IR, while post-treatment notably improve the endothelial IR both in vitro and in vivo. Moreover, TZDs substantially increase the levels of endothelial nitric oxide synthase (eNOS) and inhibitory κB alpha (IκBα), whereas decrease those of the phosphorylated inhibitory κB kinase alpha/beta (phosphor-IKKα/ß) and the cytokines including tumor necrosis factor alpha (TNFα), interleukin-6 (IL-6), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cellular adhesion molecule-1 (sVCAM-1), suggesting that TZDs act indeed through a PPARγ-dependent NF-κB trans-repression pathway. These findings highlighted a non-canonical mechanism for TZDs to ameliorate endothelial IR which might provide a potential strategy to prevent and treat the diabetic vascular complications clinically.