Observation of frustrated chiral dynamics in an interacting triangular flux ladder.

Quantum matter interacting with gauge fields, an outstanding paradigm in modern physics, underlies the description of various physical systems. Engineering artificial gauge fields in ultracold atoms offers a highly controllable access to the exotic many-body phenomena in these systems, and has stimulated intense interest. Here we implement a triangular flux ladder in the momentum space of ultracold 133Cs atoms, and study the chiral dynamics under tunable interactions. Through measurements of the site-resolved density evolutions, we reveal how the competition between interaction and flux in the frustrated triangular geometry gives rise to flux-dependent localization and biased chiral dynamics. For the latter in particular, the symmetry between the two legs is dynamically broken, which can be attributed to frustration. We then characterize typical dynamic patterns using complementary observables. Our work opens the avenue toward exploring correlated transport in frustrated geometries, where the interplay between interactions and gauge fields plays a key role.

Endoscopic botulinum toxin injection combined with balloon dilatation for treatment of cricopharyngeal achalasia in patient with brainstem stroke. / æ¶ˆåŒ–å† é•œå¼•å¯¼ä¸‹è‚‰æ¯’æ¯’ç´ æ³¨å°„è”åˆçƒå›Šæ‰©å¼ æ²»ç–—è„‘å¹²æ¢—æ­»åŽçŽ¯å’½è‚Œå¤±å¼›ç¼“çš„æ•ˆæžœ.

OBJECTIVES: At present, there are many reports about the treatment of cricopharyngeal achalasia by injecting botulinum toxin type A (BTX-A) into cricopharyngeal muscle guided by ultrasound, electromyography or CT in China, but there is no report about injecting BTX-A into cricopharyngeal muscle guided by endoscope. This study aims to evaluate the efficacy of endoscopic BTX-A injection combined with balloon dilatation in the treatment of cricopharyngeal achalasia after brainstem stroke, and to provide a better method for the treatment of dysphagia after brainstem stroke. METHODS: From June to December 2022, 30 patients with cricopharyngeal achalasia due to brainstem stroke were selected from the Department of Rehabilitation Medicine, the First Hospital of Changsha. They were randomly assigned into a control group and a combined group, 15 patients in each group. Patients in both groups were treated with routine rehabilitation therapy, while patients in the control group were treated with balloon dilatation, and patients in the combined group were treated with balloon dilatation and BTX-A injection. Before treatment and after 2 weeks of treatment, the patients were examined by video fluoroscopic swallowing study, Penetration-aspiration Scale (PAS), Dysphagia Outcome Severity Scale (DOSS), and Functional Oral Intake Scale (FOIS) were used to assess the swallowing function. RESULTS: In the combined group, 1 patient withdrew from the treatment because of personal reasons. Two weeks after treatment, the scores of DOSS, PAS, and FOIS in both groups were better than those before treatment (all P<0.01), and the combined group was better than the control group (all P<0.001). The effective rate was 85.7% in the combined group and 66.7% in the control group, with no significant difference between the 2 groups (P>0.05). CONCLUSIONS: BTX-A injection combined with balloon dilatation is more effective than balloon dilatation alone in improving swallowing function and is worthy of clinical application.

Genetic and transcriptomic dissection of an artificially induced paired spikelets mutant of wheat (Triticum aestivum L.).

KEY MESSAGE: Morphological, genetic and transcriptomic characterizations of an EMS-induced wheat paired spikelets (PS) mutant were performed. A novel qualitative locus WPS1 on chromosome 1D was identified. Grain yield of wheat is significantly associated with inflorescence or spike architecture. However, few genes related to wheat spike development have been identified and their underlying mechanisms are largely unknown. In this study, we characterized an ethyl methanesulfonate (EMS)-induced wheat mutant, wheat paired spikelets 1 (wps1). Unlike a single spikelet that usually develops at each node of rachis, a secondary spikelet appeared below the primary spikelet at most of the rachis nodes of wps1. The microscope observation showed that the secondary spikelet initiated later than the primary spikelet. Genetic analysis suggested that the PS of wps1 is controlled by a single dominant nuclear gene, designated WHEAT PAIRED SPIKELETS 1 (WPS1). Further RNA-seq based bulked segregant analysis and molecular marker mapping localized WPS1 in an interval of 208.18-220.92 Mb on the chromosome arm 1DL, which is different to known genes related to spike development in wheat. By using wheat omics data, TraesCS1D02G155200 encoding a HD-ZIP III transcription factor was considered as a strong candidate gene for WPS1. Transcriptomic analysis indicated that PS formation in wps1 is associated with auxin-related pathways and may be regulated by networks involving TB1, Ppd1, FT1, VRN1, etc. This study laid the solid foundation for further validation of the causal gene of WPS1 and explored its regulatory mechanism in PS formation and inflorescence development, which may benefit to kernel yield improvement of wheat based on optimization or design of spike architecture in the future.

High-resolution detection of quantitative trait loci for seven important yield-related traits in wheat (Triticum aestivum L.) using a high-density SLAF-seq genetic map.

BACKGROUND: Yield-related traits including thousand grain weight (TGW), grain number per spike (GNS), grain width (GW), grain length (GL), plant height (PH), spike length (SL), and spikelet number per spike (SNS) are greatly associated with grain yield of wheat (Triticum aestivum L.). To detect quantitative trait loci (QTL) associated with them, 193 recombinant inbred lines derived from two elite winter wheat varieties Chuanmai42 and Chuanmai39 were employed to perform QTL mapping in six/eight environments. RESULTS: A total of 30 QTLs on chromosomes 1A, 1B, 1D, 2A, 2B, 2D, 3A, 4A, 5A, 5B, 6A, 6D, 7A, 7B and 7D were identified. Among them, six major QTLs QTgw.cib-6A.1, QTgw.cib-6A.2, QGw.cib-6A, QGl.cib-3A, QGl.cib-6A, and QSl.cib-2D explaining 5.96-23.75% of the phenotypic variance were detected in multi-environments and showed strong and stable effects on corresponding traits. Three QTL clusters on chromosomes 2D and 6A containing 10 QTLs were also detected, which showed significant pleiotropic effects on multiple traits. Additionally, three Kompetitive Allele Specific PCR (KASP) markers linked with five of these major QTLs were developed. Candidate genes of QTgw.cib-6A.1/QGl.cib-6A and QGl.cib-3A were analyzed based on the spatiotemporal expression patterns, gene annotation, and orthologous search. CONCLUSIONS: Six major QTLs for TGW, GL, GW and SL were detected. Three KASP markers linked with five of these major QTLs were developed. These QTLs and KASP markers will be useful for elucidating the genetic architecture of grain yield and developing new wheat varieties with high and stable yield in wheat.

Genetic dissection of quantitative trait loci for grain size and weight by high-resolution genetic mapping in bread wheat (Triticum aestivum L.).

KEY MESSAGE: Six major QTLs for wheat grain size and weight were identified on chromosomes 4A, 4B, 5A and 6A across multiple environments, and were validated in different genetic backgrounds. Grain size and weight are crucial components of wheat yield. Dissection of their genetic control is thus essential for the improvement of yield potential in wheat breeding. We used a doubled haploid (DH) population to detect quantitative trait loci (QTLs) for grain width (GW), grain length (GL), and thousand grain weight (TGW) in five environments. Six major QTLs, QGw.cib-4B.2, QGl.cib-4A, QGl.cib-5A.1, QGl.cib-6A, QTgw.cib-4B, and QTgw.cib-5A, were consistently identified in at least three individual environments and in best linear unbiased prediction (BLUP) datasets, and explained 5.65-34.06% of phenotypic variation. QGw.cib-4B.2, QTgw.cib-4B, QGl.cib-5A.1 and QGl.cib-6A had no effect on grain number per spike (GNS). In addition to QGl.cib-4A, the other major QTLs were further validated by using Kompetitive Allele Specific PCR (KASP) markers in different genetic backgrounds. Moreover, significant interactions between the three major GL QTLs and two major TGW QTLs were observed. Comparison analysis showed that QGl.cib-5A.1 and QGl.cib-6A are likely new loci. Notably, QGw.cib-4B.2 and QTgw.cib-4B were co-located on chromosome 4B and improved TGW by increasing only GW, unlike nearby or overlapped loci reported previously. Three genes associated with grain development within the QGw.cib-4B.2/QTgw.cib-4B interval were identified by searches on sequence similarity, spatial expression patterns, and orthologs. The major QTLs and KASP markers reported here will be useful for elucidating the genetic architecture of grain size and weight and for developing new wheat cultivars with high and stable yield.

Identification of HvLRX, a new dehydration and light responsive gene in Tibetan hulless barley (Hordeum vulgare var. nudum).

BACKGROUND: Tibetan hulless barley (Hordeum vulgare var. nudum), adjusting to the harsh environment on Qinghai-Tibet Plateau, is a good subject for analyzing drought tolerance mechanism. Several unannotated differentially expressed genes (DEGs) were identified through our previous RNA-Seq study using two hulless barley accessions with contrasting drought tolerance. One of these DEGs, HVU010048.2, showed up-regulated pattern under dehydration stress in both drought tolerant (DT) and drought susceptible (DS) accessions, while its function in drought resistance remains unknown. This new gene was named as HvLRX (light responsive X), because its expression was induced under high light intensity while suppressed under dark. OBJECTIVE: To provide preliminary bioinformatics prediction, expression pattern, and drought resistance function of this new gene. METHODS: Bioinformatics analysis of HvLRX were conducted by MEGA, PlantCARE, ProtParam, CELLO et al. The expression pattern of HvLRX under different light intensity, dehydration shock, gradual drought stress, NaCl stress, polyethylene glycol (PEG) 6000 stress and abscisic acid (ABA) treatment was investigated by quantitative reverse transcription-polymerase chain reaction (RT-qPCR). The function of HvLRX was analyzed by virus induced gene silencing (VIGS) in hulless barley and by transgenic method in tobacco. RESULTS: Full cDNAs of HvLRX were cloned and compared in three hulless barley accessions. Homologues of HvLRX protein in other plants were excavated and their phylogenetic relationship was analyzed. Several light responsive elements (ATC-motif, Box 4, G-box, Sp1, and chs-CMA1a) were identified in its promoter region. Its expression can be promoted under high light intensity, dehydration shock, gradual drought stress, PEG 6000, and NaCl stress, but was almost unchanged in ABA treatment. HvLRX-silenced plants had a higher leaf water loss rate (WLR) and a lower survival rate (SR) compared with controls under dehydration stress. The infected leaves of HvLRX-silenced plants lost their water content quickly and became withered at 10 dpi. The SR of HvLRX overexpressed transgenic tobacco plants was significantly higher than that of wild-type plants. These results indicated HvLRX play a role in drought resistance. Besides, retarded vegetative growth was detected in HvLRX-silenced hulless barley plants, which suggested that this gene is important for plant development. CONCLUSIONS: This study provided data of bioinformatics, expression pattern, and function of HvLRX. To our knowledge, this is the first report of this new dehydration and light responsive gene.

Identification and validation of two major QTLs for spike compactness and length in bread wheat (Triticum aestivum L.) showing pleiotropic effects on yield-related traits.

KEY MESSAGE: Two major and stable QTLs for spike compactness and length were detected and validated in multiple genetic backgrounds and environments, and their pleiotropic effects on yield-related traits were analyzed. Spike compactness (SC) and length (SL) are greatly associated with wheat (Triticum aestivum L.) grain yield. To detect quantitative trait loci (QTL) associated with SC and SL, two biparental populations derived from crosses of Chuanmai42/Kechengmai1 and Chuanmai42/Chuannong16 were employed to perform QTL mapping in five environments. A total of 34 QTLs were identified, in which six major QTLs were repeatedly detected in more than four environments and the best linear unbiased prediction datasets, explaining 7.13-33.6% of phenotypic variation. These major QTLs were co-located in two genomic regions on chromosome 5A and 6A, namely QSc/Sl.cib-5A and QSc/Sl.cib-6A, respectively. By developing kompetitive allele-specific PCR (KASP) markers that linked to them, the two loci were validated in different genetic backgrounds, and their interactions were also analyzed. Comparison analysis showed that QSc/Sl.cib-5A was not Vrn-A1 and Q, and QSc/Sl.cib-6A was likely a new locus for SC and SL. Both QSc/Sl.cib-5A and QSc/Sl.cib-6A had pleiotropic effects on other yield-related traits including plant height, thousand grain weight and grain length. Therefore, the two loci combined with the developed KASP markers might be potentially applicable in wheat breeding. Furthermore, based on the spatiotemporal expression patterns, gene annotation, orthologous search and sequence differences, TraesCS5A01G301400 and TraesCS6A01G090300 were considered as potential candidates for QSc/Sl.cib-5A and QSc/Sl.cib-6A, respectively. These results provided valuable information for fine mapping and cloning of the two loci in the future.

Genetic and molecular characterization of determinant of six-rowed spike of barley carrying vrs1.a4.

KEY MESSAGE: Decisive role of reduced vrs1 transcript abundance in six-rowed spike of barley carrying vrs1.a4 was genetically proved and its potential causes were preliminarily analyzed. Six-rowed spike 1 (vrs1) is the major determinant of the six-rowed spike phenotype of barley (Hordeum vulgare L.). Alleles of Vrs1 have been extensively investigated. Allele vrs1.a4 in six-rowed barley is unique in that it has the same coding sequence as Vrs1.b4 in two-rowed barley. The determinant of row-type in vrs1.a4 carriers has not been experimentally identified. Here, we identified Vrs1.b4 in two-rowed accessions and vrs1.a4 in six-rowed accessions from the Qinghai-Tibet Plateau at high frequency. Genetic analyses revealed a single nuclear gene accounting for row-type alteration in these accessions. Physical mapping identified a 0.08-cM (~ 554-kb) target interval on chromosome 2H, wherein Vrs1 was the most likely candidate gene. Further analysis of Vrs1 expression in offspring of the mapping populations or different Vrs1.b4 and vrs1.a4 lines confirmed that downregulated expression of vrs1.a4 causes six-rowed spike. Regulatory sequence analysis found a single 'TA' dinucleotide deletion in vrs1.a4 carriers within a 'TA' tandem-repeat-enriched region ~ 1 kb upstream of the coding region. DNA methylation levels did not correspond to the expression difference and therefore did not affect Vrs1 expression. More evidence is needed to verify the causal link between the 'TA' deletion and the downregulated Vrs1 expression and hence the six-rowed spike phenotype.

PAL-mediated SA biosynthesis pathway contributes to nematode resistance in wheat.

The pathogen cereal cyst nematode (CCN) is deleterious to Triticeae crops and is a threat to the global crop yield. Accession no. 1 of Aegilops variabilis, a relative of Triticum aestivum (bread wheat), is highly resistant to CCN. Our previous study demonstrated that the expression of the phenylalanine ammonia lyase (PAL) gene AevPAL1 in Ae. variabilis is strongly induced by CCN. PAL, the first enzyme of phenylpropanoid metabolism, is involved in abiotic and biotic stress responses. However, its role in plant-CCN interaction remains unknown. In the present study, we proved that AevPAL1 helps to confer CCN resistance through affecting the synthesis of salicylic acid (SA) and downstream secondary metabolites. The silencing of AevPAL1 increased the incidence of CCN infection in roots and decreased the accumulation of SA and phenylalanine (Phe)-derived specialized metabolites. The exogenous pre-application of SA also improved CCN resistance. Additionally, the functions of PAL in phenylpropanoid metabolism correlated with tryptophan decarboxylase (TDC) functioning in tryptophan metabolism pathways. The silencing of either AevPAL1 or AevTDC1 exhibited a concomitant reduction in the expression of both genes and the contents of metabolites downstream of PAL and TDC. These results suggested that AevPAL1, possibly in coordination with AevTDC1, positively contributes to CCN resistance by altering the downstream secondary metabolites and SA content in Ae. variabilis. Moreover, AevPAL1 overexpression significantly enhanced CCN resistance in bread wheat and did not exhibit significant negative effects on yield-related traits, suggesting that AevPAL1 is valuable for the genetic improvement of CCN resistance in bread wheat.

Identification and candidate gene mining of HvSS1, a novel qualitative locus on chromosome 6H, regulating the uppermost internode elongation in barley (Hordeum vulgare L.).

KEY MESSAGE: A novel qualitative locus regulating the uppermost internode elongation of barley was identified and mapped on 6H, and the candidate gene mining was performed by employing various barley genomic resources. The stem of grass crops, such as barley and wheat, is composed of several interconnected internodes. The extent of elongation of these internodes determines stem height, and hence lodging, canopy architecture, and grain yield. The uppermost internode (UI) is the last internode to elongate. Its elongation contributes largely to stem height and facilitates spike exsertion, which is crucial for final grain yield. Despite the molecular mechanism underlying regulation of UI elongation was extensively investigated in rice, little is known in barley. In this study, we characterized a barley spontaneous mutant, Sheathed Spike 1 (SS1), showing significantly shortened UI and sheathed spike (SS). The extension of UI parenchyma cell in SS1 was significantly suppressed. Exogenous hormone treatments and RNA-seq analysis indicated that the suppression of UI elongation is possibly related to insufficient content of endogenous bioactive gibberellin. Genetic analysis showed that SS1 is possibly controlled by a qualitative dominant nuclear factor. Bulked segregant analysis and further molecular marker mapping identified a novel major locus, HvSS1, in a recombination cold spot expanding 173.44-396.33 Mb on chromosome 6H. The candidate gene mining was further conducted by analyzing sequence differences, spatiotemporal expression patterns, and variant distributions of genes in the candidate interval by employing various barley genomic resources of worldwide collections of barley accessions. This study made insight into genetic control of UI elongation in barley and laid a solid foundation for further gene cloning and functional characterization. The results obtained here also provided valuable information for similar research in wheat.

Identification and Validation of a Novel Locus Controlling Spikelet Number in Bread Wheat (Triticum aestivum L.).

Spikelet number is an important target trait for wheat yield improvement. Thus, the identification and verification of novel quantitative trait locus (QTL)/genes controlling spikelet number are essential for dissecting the underlying molecular mechanisms and hence for improving grain yield. In the present study, we constructed a high-density genetic map for the Kechengmai1/Chuanmai42 doubled haploid (DH) population using 13,068 single-nucleotide polymorphism (SNP) markers from the Wheat 55K SNP array. A comparison between the genetic and physical maps indicated high consistence of the marker orders. Based on this genetic map, a total of 27 QTLs associated with total spikelet number per spike (TSN) and fertile spikelet number per spike (FSN) were detected on chromosomes 1B, 1D, 2B, 2D, 3D, 4A, 4D, 5A, 5B, 5D, 6A, 6B, and 7D in five environments. Among them, five QTLs on chromosome 2D, 3D, 5A, and 7D were detected in multiple environments and combined QTL analysis, explaining the phenotypic variance ranging from 3.64% to 23.28%. Particularly, QTsn/Fsn.cib-3D for TSN and FSN [phenotypic variation explained (PVE) = 5.97-23.28%, limit of detection (LOD) = 3.73-18.51] is probably a novel locus and located in a 4.5-cM interval on chromosome arm 3DL flanking by the markers AX-110914105 and AX-109429351. This QTL was further validated in other two populations with different genetic backgrounds using the closely linked Kompetitive Allele-Specific PCR (KASP) marker KASP_AX-110914105. The results indicated that QTsn/Fsn.cib-3D significantly increased the TSN (5.56-7.96%) and FSN (5.13-9.35%), which were significantly correlated with grain number per spike (GNS). We also preliminary analyzed the candidate genes within this locus by sequence similarity, spatial expression patterns, and collinearity analysis. These results provide solid foundation for future fine mapping and cloning of QTsn/Fsn.cib-3D. The developed and validated KASP markers could be utilized in molecular breeding aiming to increase the grain yield in wheat.

MiR-874 Inhibits Cell Proliferation, Migration, and Invasion of Glioma Cells and Correlates with Prognosis of Glioma Patients.

Previous studies showed that miR-874 expression was abnormally expressed in many tumors. However, the potential role of miR-874 in glioma remains a mystery. This study aimed to investigate its expression, clinical significance, and cellular function in glioma. A total of 105 glioma patients were enrolled in the present study. The RT-qPCR analysis was used to detect the expression of miR-874 in glioma tissues and cells. The χ2 test was used to analyze the association between miR-874 expression and clinical characteristics of patients. Kaplan-Meier method and multivariate Cox regression assays were used to analyze the prognostic value of miR-874 in glioma. Cell counting kit-8 and Transwell assays were used to explore the alterations in a series of cancer-related phenotypes affected by miR-874, including cell proliferation, migration, and invasion capacities. The expression of miR-874 was significantly downregulated in human glioma tissue specimens and cell lines. Furthermore, the expression of miR-874 was associated with tumor size, KPS, and WHO grade. The decreased expression of miR-874 was associated with shorter overall survival. Then functional assays indicated that upregulation of miR-874 suppressed proliferation, migration, and invasion of glioma cells in vitro. The present study indicated that miR-874 inhibited cell proliferation, migration, and invasion of glioma cells and might be a novel prognostic biomarker and potential therapeutic target for glioma.

MicroRNA-503-5p improves carotid artery stenosis by inhibiting the proliferation of vascular smooth muscle cells.

Carotid artery stenosis (CAS) is a common arteriosclerotic vascular disease affected by vascular smooth muscle cells (VSMCs). The aim of the present study was to investigate the expression and diagnostic value of microRNA (miR)-503-5p in asymptomatic patients with CAS and to further explore the effect of miR-503-5p on VSMC proliferation. The levels of miR-503-5p in the serum of 62 asymptomatic patients with CAS and 60 healthy controls were detected by reverse transcription-quantitative PCR. The association between miR-503-5p and the clinical characteristics of the patients was analyzed using the χ2 test. A receiver operating characteristic curve was drawn to evaluate the diagnostic value of miR-503-5p to distinguish asymptomatic patients with CAS from healthy controls. Finally, miR-503-5p inhibitors and mimics were transfected into VSMCs in vitro to detect the effect of miR-503-5p on the proliferation ability through Cell Counting Kit-8 assays. The serum levels of miR-503-5p in asymptomatic patients with CAS were significantly reduced as compared with those in healthy individuals. The expression levels of miR-503-5p were significantly associated with diabetes and arterial stenosis. Furthermore, the area under the ROC curve was 0.817, the specificity was 79.03% and the sensitivity was 83.30%, which proved that miR-503-5p had a high diagnostic accuracy in patients with CAS. Finally, the in vitro proliferation assay indicated that overexpression of miR-503-5p significantly inhibited the proliferation of VSMCs. In conclusion, miR-503-5p is a potential diagnostic biomarker for asymptomatic CAS and overexpression of miR-503-5p may inhibit the proliferation of VSMCs and improve CAS.

Quantitative Trait Locus (QTLs) Mapping for Quality Traits of Wheat Based on High Density Genetic Map Combined With Bulked Segregant Analysis RNA-seq (BSR-Seq) Indicates That the Basic 7S Globulin Gene Is Related to Falling Number.

Numerous quantitative trait loci (QTLs) have been identified for wheat quality; however, most are confined to low-density genetic maps. In this study, based on specific-locus amplified fragment sequencing (SLAF-seq), a high-density genetic map was constructed with 193 recombinant inbred lines derived from Chuanmai 42 and Chuanmai 39. In total, 30 QTLs with phenotypic variance explained (PVE) up to 47.99% were identified for falling number (FN), grain protein content (GPC), grain hardness (GH), and starch pasting properties across three environments. Five NAM genes closely adjacent to QGPC.cib-4A probably have effects on GPC. QGH.cib-5D was the only one detected for GH with high PVE of 33.31-47.99% across the three environments and was assumed to be related to the nearest pina-D1 and pinb-D1genes. Three QTLs were identified for FN in at least two environments, of which QFN.cib-3D had relatively higher PVE of 16.58-25.74%. The positive effect of QFN.cib-3D for high FN was verified in a double-haploid population derived from Chuanmai 42 × Kechengmai 4. The combination of these QTLs has a considerable effect on increasing FN. The transcript levels of Basic 7S globulin and Basic 7S globulin 2 in QFN.cib-3D were significantly different between low FN and high FN bulks, as observed through bulk segregant RNA-seq (BSR). These QTLs and candidate genes based on the high-density genetic map would be beneficial for further understanding of the genetic mechanism of quality traits and molecular breeding of wheat.

Corrigendum: The Tryptophan decarboxylase 1 Gene From Aegilops variabilis No.1 Regulate the Resistance Against Cereal Cyst Nematode by Altering the Downstream Secondary Metabolite Contents Rather Than Auxin Synthesis.

[This corrects the article DOI: 10.3389/fpls.2018.01297.].

Knockdown long non-coding RNA PEG10 inhibits proliferation, migration and invasion of glioma cell line U251 by regulating miR-506.

Glioma is a serious malignant tumor without effective therapies till now. lncRNA PEG10 was reported to have some biological activities in cancers. Hence, we explored the effects of PEG10 on the human glioma cell line U251 cells. U251 cells were transfected with sh-PEG10 and/or miR-506 inhibitor. The expression of PEG10 and miR-506 was measured by qRT-PCR. Cell viability, cell apoptosis, cell migration and invasion were detected by CCK-8 assay, flow cytometry and Transwell chamber assay, respectively. The cell proliferation and apoptosis related p16, p53, Bcl-2, Bax, and pro-/Cleaved-Caspase-3/9, migration and invasion related-protein: matrix metalloproteinases MMP-2, MMP-9 and vimentin, and Raf/MEK/ERK and JAK1/STAT3 pathways-related proteins were accessed by Western blot. Transfection with sh-PEG10 inhibited cell viability, migration and invasion, and increased cell apoptosis. Meanwhile, PEG10 silence upregulated the expression of p16 and p53, Bax, cleaved-Caspase-3/9 expression, and downregulated Bcl-2 expression. PEG10 silence upregulated miR-506 expression. Co-transfection with sh-PEG10 and miR-506 inhibitor impaired the tumor suppressive effects. PEG10 knockdown decreased the phosphorylation of Raf/MEK/ERK and JAK1/STAT3-related proteins Raf, MEK, ERK, JAK1 and STAT3. PEG10 knockdown inhibited cell viability, migration and invasion, induced cell apoptosis through miR-506 upregulation, as well as inactivation of Raf/MEK/ERK and JAK1/STAT3 signal pathways.

Knockdown of lncRNA-UCA1 inhibits cell viability and migration of human glioma cells by miR-193a-mediated downregulation of CDK6.

BACKGROUND: Long noncoding RNA urothelial carcinoma-associated 1 (lncRNA-UCA1) is generally recognized as an oncogenic molecule in several human malignant tumors. However, the available evidence does not necessarily imply an unequivocal causal function of UCA1 in glioblastoma. The current study was aimed to probe the biological function of lncRNA-UCA1 in human glioblastoma cell lines. Besides, we further investigated the potential mechanisms. METHODS: Cell viability, apoptosis, as well as migration and invasion were measured using a commercial cell counting kit-8, flow cytometry, and 24-Transwell assay, respectively. LncRNA-UCA1, microRNA-193a (miR-193a), and CDK6 at messenger RNA levels were evaluated by quantitative real-time polymerase chain reaction method. Protein level was examined by Western blot analysis. RNA immunoprecipitation was utilized to validate lncRNA-UCA1 associated with miR-193a. Luciferase activity assay was used to identify the miR-193a-targeted CDK6 3'-untranslated region. RESULTS: lncRNA-UCA1 knockdown weakened cell viability, augmented apoptosis progression, as well as suppressed migration and invasion behaviors in glioblastoma cells, whereas lncRNA-UCA1 silence exhibited the opposite functions. lncRNA-UCA1 functioned as an endogenous sponge of miR-193a. miR-193a silence reversed the biological function of lncRNA-UCA1 knockdown on U-118 MG cells. miR-193a negatively regulated the expression of CDK6, and it affected the U-118 MG cells through regulating CDK6 expression. CDK6 overexpression abrogated the blockage of PI3K/AKT, mitogen-activated protein kinase (MAPK), and Notch signaling pathways. Furthermore, lncRNA-UCA1 and miR-193a could affect these signaling cascades through regulating CDK6 expression. The regulatory mechanisms of lncRNA-UCA1 were further consolidated in clinical specimens. CONCLUSION: lncRNA-UCA1 silence reduced cell viability, promoted apoptosis progression, while impeding the migration and invasion of glioblastoma cells by miR-193a-mediated silence of CDK6, with blockage of PI3K/AKT, MAPK, and Notch pathways.

Structural organization and functional divergence of high isoelectric point α-amylase genes in bread wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.).

BACKGROUND: High isoelectric point α-amylase genes (Amy1) play major roles during cereal seed germination, and are associated with unacceptable high residual α-amylase activities in ripe wheat grains. However, in wheat and barley, due to extremely high homology of duplicated copies, and large and complex genome background, the knowledge on this multigene family is limited. RESULTS: In the present work, we identified a total of 41 Amy1 genes among 13 investigated grasses. By using genomic resources and experimental validation, the exact copy numbers and chromosomal locations in wheat and barley were determined. Phylogenetic and syntenic analyses revealed tandem gene duplication and chromosomal rearrangement leading to separation of Amy1 into two distinct loci, Amy1θ and Amy1λ. The divergence of Amy1λ from Amy1θ was driven by adaptive selection pressures performed on two amino acids, Arg97 and Asn233 (P > 0.95*). The predicted protein structural alteration caused by substitution of Asp233Asn in the conserved starch binding surface site, and significantly expressional differentiation during seed germination and grain development provided evidence of functional divergence between Amy1θ and Amy1λ genes. We screened out candidate copies (TaAmy1-A1/A2 and TaAmy1-D1) associated with high residual α-amylase activities in ripe grains. Furthermore, we proposed an evolutionary model for expansion dynamics of Amy1 genes. CONCLUSIONS: Our study provides comprehensive analyses of the Amy1 multigene family, and defines the fixation of two spatially structural Amy1 loci in wheat and barley. Potential functional divergence between them is reflected by their sequence features and expressional patterns, and driven by gene duplication, chromosome rearrangement and natural selections during gene family evolution. Furthermore, the discrimination of differentially effective copies during seed germination and/or grain development will provide guidance to manipulation of α-amylase activity in wheat and barley breeding for better yield and processing properties.

New insights into the origin and evolution of α-amylase genes in green plants.

Gene duplication is a source of genetic materials and evolutionary changes, and has been associated with gene family expansion. Functional divergence of duplicated genes is strongly directed by natural selections such as organism diversification and novel feature acquisition. We show that, plant α-amylase gene family (AMY) is comprised of six subfamilies (AMY1-AMY6) that fell into two ancient phylogenetic lineages (AMY3 and AMY4). Both AMY1 and AMY2 are grass-specific and share a single-copy ancestor, which is derived from grass AMY3 genes that have undergone massive tandem and whole-genome duplications during evolution. Ancestral features of AMY4 and AMY5/AMY6 genes have been retained among four green algal sequences (Chrein_08.g362450, Vocart_0021s0194, Dusali_0430s00012 and Monegl_16464), suggesting a gene duplication event following Chlorophyceae diversification. The observed horizontal gene transfers between plant and bacterial AMYs, and chromosomal locations of AMY3 and AMY4 genes in the most ancestral green body (C. reinhardtii), provide evidences for the monophyletic origin of plant AMYs. Despite subfamily-specific sequence divergence driven by natural selections, the active site and SBS1 are well-conserved across different AMY isoforms. The differentiated electrostatic potentials and hydrogen bands-forming residue polymorphisms, further imply variable digestive abilities for a broad substrates in particular tissues or subcellular localizations.

The Tryptophan decarboxylase 1 Gene From Aegilops variabilis No.1 Regulate the Resistance Against Cereal Cyst Nematode by Altering the Downstream Secondary Metabolite Contents Rather Than Auxin Synthesis.

Cereal cyst nematode (CCN, Heterodera avenae) is a most important pathogen of wheat and causes tremendous yield loss annually over the world. Since the lack of resistance materials among wheat cultivars, identification and characterization of the resistance-related genes from the relatives of wheat is a necessary and efficient way. As a close relative of wheat with high resistance against CCN, Aegilops variabilis No.1 is believed to be a valuable source for wheat breeding against this devastating disease. However so far, very few resistance-associated genes have been characterized from this species. In this study, we present that the tryptophan decarboxylase genes from Ae. variabilis No.1 (AeVTDC1 and AeVTDC2) were both induced by CCN juveniles at the early stage of resistance response (30 h post-inoculation), with AeVTDC1 more sensitive to CCN infection than AeVTDC2. Silencing of AeVTDC1 led to compromised immunity to CCN with more CCN intrusion into roots; while overexpression AeVTDC1 in Nicotiana tabacum dramatically enhanced the resistance of plants by reducing the knots formed on roots. Metabolism analysis showed that the contents of secondary metabolites with activity of resistance to varied pathogens correlated with the expression level of AeVTDC1 in both Ae. variabilis No.1 and the transgenic tobacco plants. In addition, the content of IAA was not affected by either silencing or overexpressing of AeVTDC1. Hence, our research provided AeVTDC1 a valuable target that mediates resistance to CCN and root knot nematode (RKN, Meloidogyne naasi) without influencing the auxin biosynthesis.