Integrated transcriptome and metabolome analysis reveals the anthocyanin biosynthesis mechanisms in blueberry (Vaccinium corymbosum L.) leaves under different light qualities

IntroductionBlueberry (Vaccinium corymbosum L.) is a popular fruit with an abundance of anthocyanins in its leaves and fruits. Light is one of the pivotal environmental elements that affects plant growth and development, but the regulatory mechanism between light quality and anthocyanin formation is poorly understood.MethodsAn integrated transcriptome and metabolome analysis was performed to investigate the effects of white (control), blue (B), red (R), and red/blue (60R/40B) light on blueberry growth and reveal the potential pathway controlling anthocyanin biosynthesis in blueberry leaves.ResultsThe anthocyanin content was significantly improved by the blue and red/blue light when compared with white light, whereas there was a significant reduction in the photosynthesis under the blue light, showing an inverse trend to that of anthocyanin accumulation. Transcriptomic analysis resulted in the assembly of 134,709 unigenes. Of these, 22 were differentially expressed genes (DEGs) that participate in the anthocyanin biosynthesis pathway, with the majority being significantly up-regulated under the blue light. Most of the photosynthesis-related genes that were down-regulated were expressed during anthocyanin accumulation. Targeted metabolome profiling identified 44 metabolites associated with anthocyanin biosynthesis. The contents of most of these metabolites were higher under blue light than the other light conditions, which was consistent with the transcriptome results. The integrated transcriptome and metabolome analysis suggested that, under blue light, leucoanthocyanidin dioxygenase (LDOX), O-methyltransferase (OMT), and UDP-glucose flavonoid glucosyltransferase (UFGT) were the most significantly expressed, and they promoted the synthesis of cyanidin (Cy), malvidin (Mv), and pelargonidin (Pg) anthocyanidins, respectively. The expression levels of dihydroflavonol 4-reductase (DFR) and OMT, as well as the accumulation of delphinidin (Dp), peonidin (Pn), and petunidin (Pt), were significantly increased by the red/blue light.DiscussionThe blue and red/blue lights promoted anthocyanin biosynthesis via inducing the expression of key structural genes and accumulation of metabolites involved in anthocyanin synthesis pathway. Moreover, there was a possible feedback regulating correlation between anthocyanin biosynthesis and photosynthesis under different light qualities in blueberry leaves. This study would provide a theoretical basis for elucidating the underlying regulatory mechanism of anthocyanin biosynthesis of V. corymbosum

Genome-wide analysis of LysM gene family members and their expression in response to Colletotrichum fructicola infection in Octoploid strawberry(Fragaria × ananassa)

The cultivated octoploid strawberry (Fragaria × ananassa) is an economically important fruit that is planted worldwide. The lysin motif (LysM) protein family is composed of the major class of plant pattern recognition receptors, which play important roles in sensing pathogen-associated molecular patterns (PAMPs), and subsequently triggers downstream plant immunity. In the present study, a comprehensive, genome-wide analysis of F. × ananassa LysM (FaLysM) genes was performed to investigate gene structures, phylogenic relationships, chromosome location, collinear relationships, transcription factor binding sites, and protein model analysis. We aimed to identify the LysM genes involved in the defense against plant pathogens. A total of 14 FaLysM genes were identified in the F. × ananassa genome and divided into 2 subgroups (LYP and LYK) on the basis of the phylogenetic analysis. The Ka/Ks ratio for the duplicated pair of most FaLysM genes was less than 1, which indicates that the selection pressure was mostly subject to the purifying selection during evolution. The protein model analysis revealed that FaLysM2-10 contain conserved mode of chitin binding, which suggest the potential role of FaLysM2-10 in pathogen perception and plant immunity. The RNA-Seq results showed the differential regulation of 14 FaLysM genes in response to Colletotrichum fructicola infection, implying the complex interaction between C. fructicola and strawberry. Knockout of candidate effector gene CfLysM2, which was previously proved to be highly expressed during C. fructicola infection, resulted in the up-regulation of six FaLysM genes (FaLysM1, FaLysM2, FaLysM3, FaLysM7, FaLysM8, and FaLysM12), indicating the competitive relations between CfLysM2 and FaLysM genes. Overall, this study provides fundamental information on the roles of LysM proteins in octoploid strawberry and its interaction with C. fructicola, laying useful information for further investigation on the C. fructicola-strawberry interaction and strawberry resistance breeding

Genome-wide identification and comprehensive analysis reveal potential roles of long non-coding RNAs in fruit development of southern highbush blueberry (Vaccinium corymbosum L.)

IntroductionBlueberries have a high antioxidant content and are produced as healthy food worldwide. Long non-coding RNAs (lncRNAs) are a type of regulatory RNAs that play a variety of roles in plants. Nonetheless, information on lncRNAs and their functions during blueberry fruit development is scarce in public databases.MethodsIn the present study, we performed genome-wide identification of lncRNAs in a southern highbush blueberry using strand-specific RNA sequencing (ssRNA-Seq). Differentially expressed lncRNAs (DE-lncRNAs) and their potential target genes were analyzed at four stages of fruit development. Cis-regulatory DE-lncRNAs were predicted using co-localization analysis.ResultsThese findings included a total of 25,036 lncRNAs from 17,801 loci. Blueberry lncRNAs had shorter transcript lengths, smaller open reading frame (ORF) sizes, fewer exons, and fewer isoforms than protein-coding RNAs, as well as lower expression levels and higher stage-specificity during fruit development. A total of 105 DE-lncRNAs were identified among the comparison group of PAD vs. CUP, 443 DE-lncRNAs were detected when comparing CUP with PINK fruits, and 285 DE-lncRNAs were revealed when comparing PINK and BLUE fruits. According to Kyoto Encyclopedia of Genes and Genomes annotation, target genes of DE-lncRNAs were primarily enriched in the “Autophagy-other”, “DNA replication”, “Endocytosis”, ‘photosynthesis’ and ‘chlorophyll metabolism’ pathways, suggesting that lncRNAs may pay potential roles in fruit expansion and ripening. Moreover, several lncRNAs have been proposed as cis-regulators of the key genes involved in flavonoid biosynthesis. MSTRG.107242.6, and its putative target gene, BTB/POZ and TAZ domain-containing protein, might play critical roles in anthocyanin accumulation in blueberries.DiscussionThese findings highlight the regulatory function of lncRNAs and aid in elucidating the molecular mechanism underlying blueberry fruit growth

Metal Halide Perovskite Single Crystals: From Growth Process to Application

As a strong competitor in the field of optoelectronic applications, organic-inorganic metal hybrid perovskites have been paid much attention because of their superior characteristics, which include broad absorption from visible to near-infrared region, tunable optical and electronic properties, high charge mobility, long exciton diffusion length and carrier recombination lifetime, etc. It is noted that perovskite single crystals show remarkably low trap-state densities and long carrier diffusion lengths, which are even comparable with the best photovoltaic-quality silicon, and thus are expected to provide better optoelectronic performance. This paper reviews the recent development of crystal growth in single-, mixed-organic-cation and fully inorganic halide perovskite single crystals, in particular the solution approach. Furthermore, the application of metal hybrid perovskite single crystals and future perspectives are also highlighted

Transcriptome-Based Identification of Candidate Flowering-Associated Genes of Blueberry in a Plant Factory with Artificial Lighting (PFAL) under Short-Day-Length Conditions

In blueberry (Vaccinium corymbosum L.), a perennial shrub, flower bud initiation is mediated by a short-day (SD) photoperiod and buds bloom once the chilling requirement is satisfied. A plant factory with artificial lighting (PFAL) is a planting system that can provide a stable and highly efficient growing environment for blueberry production. However, the characteristics of bud differentiation of blueberry plants inside PFAL systems are poorly understood. To better understand flower bud initiation and the flowering mechanism of blueberry in PFAL systems, the anatomical structure of apical buds under SD conditions in a PFAL system was observed using the southern highbush cultivar ‘Misty’ and a transcriptomic analysis was performed to identify the candidate flowering genes. The results indicated that the apical bud of ‘Misty’ differentiated gradually along with SD time course and swelled obviously when chilling was introduced. A total of 39.28 Gb clean data were generated, and about 20.31–24.11 Mb high-quality clean reads were assembled, yielding a total of 17370 differentially expressed genes (DEGs), of which 9637 were up-regulated and 7733 were down-regulated. Based on the functional annotation, 26 DEGs were identified including 20 flowering-related and 6 low-temperature DEGs, out of which the expressive level of four flowering-related DEGs (VcFT2, VcFPA, VcFMADS1, and VcCOP1) and two low-temperature-induced DEGs (VcTIL-1 and VcLTI 65-like) were confirmed by qRT-PCR with a good consistency with the pattern of transcriptome. Functional analysis indicated that VcFT2 was highly conserved with nuclear and cytoplasmic subcellular localization and was expressed mainly in blueberry leaf tissue. In Arabidopsis, ectopic overexpression of VcFT2 results in an early flowering phenotype, indicating that VcFT2 is a vital regulator of the SD-mediated flowering pathway in blueberry. These results contribute to the investigation of photoperiod-mediated flowering mechanisms of blueberry in PFAL systems

Experimental investigation and thermodynamic assessment of the V-W-C system

Phase equilibrium information of the V-C, W-C and V-W systems are reviewed and the V-W phase diagram was optimized by the substitutional solution model for liquid and bcc phases. A set of self-consistent thermodynamic parameters on the interaction of W and V atoms in the fcc (V,W)C and hcp (V,W)₂C phases was established by CALPHAD techniques. The calculated isothermal section at 1500 °C was consistent with the available experimental literature data of the V-W-C system. To validate the thermodynamic calculations, V₈C₇/WC interaction couples were annealed at 1400 °C for 196 h and WC powder mixtures with 20, 40 and 70 wt.% V₈C₇ were sintered at 1400 °C for 15 h. The obtained materials were investigated by scanning electron microscopy (SEM), electron probe microanalysis (EPMA) and X-ray diffraction (XRD). The composition of the single phase fcc (VW)C reaction product in the interaction couple and the constituent phases of the sintered materials were consistent with the calculated phase diagram at 1400 °C.status: publishe

Experimental investigation and thermodynamic assessment of the Nd2O3-Y2O3 system

The phase relations in the Nd2O3-Y2O3 system were experimentally studied in the 1300 degrees-1600 degrees C range. X-ray diffraction, scanning electron microscopy, and electron probe microanalysis were applied to analyze the phase composition of annealed Nd2O3-Y2O3 mixtures with varying Y2O3 content. A thermodynamic assessment was conducted using the experimental data obtained. The excess Gibbs energies of the solution phases were described based on a simple substitutional solution model. A consistent set of optimized interaction parameters was derived for the Gibbs energy of the constituent phases, resulting in a good match between calculated and experimental data.status: publishe

Properties of NbC-Co cermets obtained by spark plasma sintering

Sub-micrometer sized NbC-Co powder mixtures with 8, 12, 18 or 24.5 wt.% Co were consolidated by spark plasma sintering (SPS) for 2 min at 1200-1280 degrees C and 30-60 MPa. The optimum densification conditions were determined by analysing the dimensional change of the NbC-12 wt.% Co powder compact. SPS for 2 min at 1280 degrees C under a pressure of 60 MPa allowed full densification of the NbC-Co cermets with limited NbC grain growth. The microstructure is characterized as a highly interconnected NbC grain network with an inhomogeneously distributed Co binder. The Vickers hardness increased from 11.70 to 15.40 GPa whereas the fracture toughness decreased from 9.0 to 5.5 MPa m(1/2) with decreasing Co content from 24.5 to 8 wt.%. (c) 2006 Elsevier B.V. All rights reserved.status: publishe

Influence of WC addition on the microstructure and mechanical properties of NbC-Co cermets

NbC-24.5 wt.% Co cermets with up to 30 wt.% WC were obtained by solid state hot pressing at 1300 degrees C under a pressure of 45 MPa for 10 min and pressureless liquid phase sintering at 1360 degrees C for 60 min. The effect of WC addition on the microstructure and mechanical properties of NbC-Co based cermets was investigated. The hot pressed cermets exhibited interconnected and irregular niobium carbide (NbC) or (Nb,W)C grains, whereas the shape of the NbC grains changed from faceted with rounded corners to spherical, as the WC content increased in the pressureless sintered cermets. The undissolved WC increased with increasing WC addition. A clear core/rim structure was observed in the hot pressed cermets with 10-30 wt.% WC additions, whereas this structure was gradually eliminated when pressureless sintering. The hardness remains nearly constant whereas the fracture toughness slightly increases with increasing WC addition. The dissolution of WC in the Co binder and NbC grains, as well as the formation of a solid solution (Nb,W)C phase were supported by thermodynamic calculations. (c) 2006 Elsevier B.V. All rights reserved.status: publishe

Thermodynamics and microstructure of Co-V₈C₇ alloy

The thermodynamic properties of the Co-V-C and CO-V₈C₇ systems are of interest for superfine cemented carbide applications. The model parameters for the Gibbs energy of the individual phases have been evaluated using the CALPHAD method by combining the recently optimized phase diagram information of the V-C, Co-C and CON system. The isothermal sections of ternary system Co-V-C at 1400 °C and 1600 °C, as well as the vertical section Of Co-V₈C₇ system were extrapolated. The calculated results, especially the liquid forming temperature Of CO-V₈C₇ system was validated with experiments by using differential scanning calorimetry (DSC) analysis. Through controlling the carbon activity, various vertical sections with different carbon activity in Co-V₈C₇ system are presented.status: publishe