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Summary The AGAMOUS‐LIKE6 (AGL6)‐like genes are ancient MADS‐box genes and are functionally studied in a few model plants. The knowledge of these genes in wheat remains limited. Here, by studying a ‘double homoeolog mutant’ of the AGL6 gene in tetraploid wheat, we showed that AGL6 was required for the development of all four whorls of floral organs with dosage‐dependent effect on floret fertility. Yeast two‐hybrid analyses detected interactions of AGL6 with all classes of MADS‐box proteins in the ABCDE model for floral organ development. AGL6 was found to interact with several additional proteins, including the G protein β and γ (DEP1) subunits. Analysis of the DEP1‐B mutant showed a significant reduction in spikelet number per spike in tetraploid wheat, while overexpression of AGL6 in common wheat increased the spikelet number per spike and hence the grain number per spike. RNA‐seq analysis identified the regulation of several meristem activity genes by AGL6, such as FUL2 and TaMADS55. Our work therefore extensively updated the wheat ABCDE model and proposed an alternative approach to improve wheat grain yield by manipulating the AGL6 gene.

Additional file 3: Enriched GO terms of 193 differentially expressed transcripts in CSSL50-1 and Asominori. Enriched GO terms of 193 differentially expressed transcripts detected by Significant Analysis Microarray software (fold change > = 2, q value < = 5%). (DOC 300 KB)

Additional file 1 : Fig. S1 FISH karyotypes of the newly synthesized hexaploid wheat. (a) Euploid plant with 2n = 42. (b) M4B: plant lacking one copy of chromosome 4B (red arrow). (c) Tri4B: plant carrying an extra copy of chromosome 4B (red arrow). (d) SegT2A: plant harbouring a duplicated segment of the short arm of chromosome 2A (red arrow). (e) N7B + SegT2A, plant lacking both copies of chromosome 7B and harbouring a duplicated segment of the short arm of chromosome 2A (red arrow). Fig. S2 FISH- and GISH-based karyotyping used to validate the aneuploid status of the SegT2A material. (a) FISH karyotype of an SHW line carrying a wild-type copy of chromosome 2A; (b) FISH karyotype of an SHW line carrying the version of chromosome 2A (arrowed) shown to include a duplication of a part of its short arm. (c) GISH karyotype of an SHW line carrying SegT2A. The karyotype suggests that the copy of chromosome 2A contains additional sequences inherited from an A-subgenome chromosome. Labelling based on the probes Oligo-pSc119.2 (red) and Oligo-pTa-535 (green). Table S1 The effect of aneuploidy on leaf length and width. *, **: means differ from one another at P ≤ 0.05 and ≤ 0.01, respectively (statistical significance was determined using Student’s t test). Comparisons were made between euploid plants and the aneuploids M4B, Tri4B and SegT2A and between N7B + SegT2A and SegT2A. Table S2 RNA-Seq reads and their alignment with the CS wheat reference genome sequence v1.0. a Uniquely aligned reads designated according to the criteria suggested by Pfeifer et al. [42]. Table S3 GO analysis of DTGs mapped to chromosomes not involved in aneuploidy.

Additional file of Transcriptome analysis of grain-filling caryopses reveals involvement of multiple regulatory pathways in chalky grain formation in rice

Additional file 4: Functional classification of 623 differentially expressed genes between CSSL50-1 and Asominori. Functional classification of 623 differentially expressed genes between CSSL50-1 and Asominori as detected by one-way ANOVA (P value

Additional file 5: Sequence of primers used for RT-PCR. A list of primers used for RT-PCR and the sequence information. (DOC 78 KB)

Additional file of Transcriptome analysis of grain-filling caryopses reveals involvement of multiple regulatory pathways in chalky grain formation in rice

Additional file of Transcriptome analysis of grain-filling caryopses reveals involvement of multiple regulatory pathways in chalky grain formation in rice

DNA methylation is dynamically involved in plant immunity, but little information is known about its roles in plant interactions with biotrophic fungi, especially in temperate grasses such as wheat (Triticum aestivum). Using wheat diploid progenitor Aegilops tauschii accession AL8/78, the genome of which has been sequenced, we assessed the extent of DNA methylation in response to infection with Blumeria graminis f. sp. tritici (Bgt), which causes powdery mildew. Upon Bgt infection, ARGONAUTE4a (AGO4a) was significantly downregulated in A. tauschii, which was accompanied by a substantial reduction in AGO4a‐sorted 24‐nt siRNA levels, especially for genes near transposable elements (TAGs). Bisulfite sequencing revealed abundant differentially methylated regions (DMRs) with CHH hypomethylation. TAGs bearing CHH‐hypomethylated DMRs were enriched for ‘response to stress’ functions, including receptor kinase, peroxidase, and pathogenesis‐related genes. Virus‐induced gene silencing (VIGS) of a DOMAINS REARRANGED METHYLASE 2 (DRM2) homolog enhanced plant resistance to Bgt. The effect of CHH hypomethylation was exemplified by the upregulation of a pathogenesis‐related β‐1,3‐glucanse gene implicated in Bgt defense. These findings support the idea that dynamic DNA methylation represents a regulatory layer in the complex mechanism of plant immunity, which could be exploited to improve disease resistance in common wheat.

With the rapid development of information technology, it is possible to use new remote sensing technology to study flood monitoring and assessment. In this paper, flood disaster caused by dike break in Poyang County, Jiangxi Province was monitored and evaluated by a combined remote sensing approach with satellite images, unmanned aerial vehicle (UAV) aerial photography and ground observation. It is aimed to construct three-dimensional monitoring through the integration of ground-air-space observations to provide flood information at different scales. Satellite remote sensing has excellent advantages in providing large-scale flood monitoring, while UAV and ground remote sensing have advantages in providing small-scale and local point observations. An effective combination of these different remote sensing means can effectively meet the actual needs for overall large scale flood monitoring and small scale local dike break rescue, which truly realizes integrated air-space-ground monitoring and emergency assessment of flood disasters. We believe that a new era of flood monitoring and assessment is expectable to make full use of these abundant data resources, which will surely further improve the scientific and technological benefits of flood control and disaster reduction.

The TCP family genes are plant-specific transcription factors and play important roles in plant development. TCPs have been evolutionarily and functionally studied in several plants. Although common wheat (Triticum aestivum L.) is a major staple crop worldwide, no systematic analysis of TCPs in this important crop has been conducted. Here, we performed a genome-wide survey in wheat and found 66 TCP genes that belonged to 22 homoeologous groups. We then mapped these genes on wheat chromosomes and found that several TCP genes were duplicated in wheat including the ortholog of the maize TEOSINTE BRANCHED 1. Expression study using both RT-PCR and in situ hybridization assay showed that most wheat TCP genes were expressed throughout development of young spike and immature seed. Cis-acting element survey along promoter regions suggests that subfunctionalization may have occurred for homoeologous genes. Moreover, protein–protein interaction experiments of three TCP proteins showed that they can form either homodimers or heterodimers. Finally, we characterized two TaTCP9 mutants from tetraploid wheat. Each of these two mutant lines contained a premature stop codon in the A subgenome homoeolog that was dominantly expressed over the B subgenome homoeolog. We observed that mutation caused increased spike and grain lengths. Together, our analysis of the wheat TCP gene family provides a start point for further functional study of these important transcription factors in wheat.

The morphology and cytology of T. turgidum LDN (AABB), A. tauschii AS60 (DD), the allotriploid LDN × AS60 (ABD) and the derived allohexaploid (AABBDD). Figure S2. Global characterization of gene expression patterns among the F1 hybrids and S1 progeny and their progenitors for two compositions. Figure S3. Variation in the transcription of homoelogues as a result of allotriploidization and WGD in the LDN × AS60 lineage. Figure S4. Non-additive transcription of genes in the allotriploid and allohexaploid in the lineage LDN × AS60. Figure S5. The transcription of singletons in the LDN × AS60 lineage. Table S1. Statistics for HC1-HC4 gene expression levels. Table S2. Classification of 89,315 high confidence Chinese Spring gene models. Table S3. Dynamic homoeolog expression patterns for parental expression level dominance genes. Table S4. Homoeolog dynamics in F1 and S1 relative to those in their parents. Table S5. Comparison of the mapping efficiency of clean reads from Ae. tauschii AS60 against different reference genomes. (DOC 571 kb)

Calcium-dependent protein kinases (CPKs) are important Ca2+ signalling components involved in complex immune and stress signalling networks; but the knowledge of CPK gene functions in the hexaploid wheat is limited. Previously, TaCPK2 was shown to be inducible by powdery mildew (Blumeria graminis tritici, Bgt) infection in wheat. Here, its functions in disease resistance are characterized further. This study shows the presence of defence-response and cold-response cis-elements on the promoters of the A subgenome homoeologue (TaCPK2-A) and D subgenome homoeologue (TaCPK2-D), respectively. Their expression patterns were then confirmed by quantitative real-time PCR (qRT-PCR) using genome-specific primers, where TaCPK2-A was induced by Bgt treatment while TaCPK2-D mainly responded to cold treatment. Downregulation of TaCPK2-A by virus-induced gene silencing (VIGS) causes loss of resistance to Bgt in resistant wheat lines, indicating that TaCPK2-A is required for powdery mildew resistance. Furthermore, overexpression of TaCPK2-A in rice enhanced bacterial blight (Xanthomonas oryzae pv. oryzae, Xoo) resistance. qRT-PCR analysis showed that overexpression of TaCPK2-A in rice promoted the expression of OsWRKY45-1, a transcription factor involved in both fungal and bacterial resistance by regulating jasmonic acid and salicylic acid signalling genes. The opposite effect was found in wheat TaCPK2-A VIGS plants, where the homologue of OsWRKY45-1 was significantly repressed. These data suggest that modulation of WRKY45-1 and associated defence-response genes by CPK2 genes may be the common mechanism for multiple disease resistance in grass species, which may have undergone subfunctionalization in promoters before the formation of hexaploid wheat.

To evaluate whether garlicin can attenuate reperfusion no-reflow in a catheter-based porcine model of acute myocardial infarction (AMI).Twenty-two swine were used: six in a sham-operation group, and eight each in the control and garlicin groups. The distal part of the left anterior descending coronary artery (LAD) in the latter two groups was occluded by a dilated balloon for 2 hr, then reperfused for 3 hr. Garlicin (1.88mg/kg) was injected just before reperfusion until reperfusion for 1 hr in the garlicin group. Hemodynamic data were examined before AMI, 2 hr after occlusion, and 3 hr after reperfusion. Myocardial contrast echocardiography (MCE) and pathological staining were performed to evaluate the myocardial no-reflow area (NRA). Serum proinflammatory cytokines and endothelin (ET)-1 were examined by radioimmunoassay.Left ventricular systolic pressure (LVSP) and left ventricular end-diastolic pressure (LVEDP) significantly improved in the garlicin group after reperfusion compared with the control group and also 2hr after AMI (p0.05 for both). MCE and pathological staining both showed garlicin attenuated reperfusion NRA after AMI (p0.05, p0.01). Garlicin not only decreased serum interleukin (IL)-6 and tumor necrosis factor (TNF)-α after reperfusion (p0.05 for both), but also ET-1 level (p0.01).Garlicin attenuated reperfusion no-reflow in our catheter-based porcrine model of AMI, possibly through decreasing serum proinflammatory cytokines and ET-1.

Paracentric inversion is known to inhibit genetic recombination between normal and inverted chromosomal segments in heterozygous arrangements. Insect inversion polymorphisms have been studied to reveal adaptive processes for maintaining genetic variation. We report the first paracentric inversion in rice (Oryza sativa), which was discovered in our effort to clone the floral organ number gene FON3. Recombination at the FON3 locus on the long arm of chromosome 11 was severely suppressed over a distance of more than 36 cM. An extensive screening among 8,242 F(2) progeny failed to detect any recombinants. Cytological analysis revealed a loop-like structure on pachytene chromosomes, whereas FISH analysis showed the migration of a BAC clone from a distal location to a position closer to the centromere. Interestingly, the locations where the genetic recombination suppression began were coincided with the positions of two physical gaps on the chromosome 11, suggesting a correlation between the physical gaps, the inversion breakpoints. Transposons and retrotransposons, and tandemly arranged members of gene families were among the sequences immediately flanking the gaps. Taken together, we propose that the genetic suppression at the FON3 locus was caused by a paracentric inversion. The possible genetic mechanism causing such a spontaneous inversion was proposed.

A new method is developed for three-dimensional stress analysis of laminated piezoelectric cylindrical shell with simple support. The shell can be subjected to various applied loadings, including distributed body force, inner and outer surface traction and potential. Each layer of the shell can be piezoelectric or elastic/dielectric, with perfect bonding assumed between each interface. The governing equations are solved by the state-space technique. Numerical results are presented to show the sensing and actuating effects of three-layered piezoelectric cylindrical shell.