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Summary: Rapeseed (Brassica napus) silique is the major carbohydrate source for seed development, and the final silique length has attracted great attention from breeders. However, no studies had focused on the dynamic character of silique elongation length (SEL). Here, the dynamic SEL investigation in a natural population including 588 lines over two years indicate that dynamic SEL during 0–20 days after flowering was the most essential stage associated with seed number per silique (SPS) and thousand seed weight (TSW). Then, nine loci were identified to be associated with SEL based on GWAS analysis, among which five SNPs (over 50%) distributed on the A02 chromosome within 6.08 to 6.48 Mb. Subsequently, we screened 5078 differentially expressed genes between two extreme materials. An unknown protein, BnaA02.SE, was identified combining with GWAS and RNA‐Seq analysis. Subcellular localization and expression profiles analysis demonstrated that BnaA02.SE is a chloroplast‐ and nucleus‐localized protein mainly expressed in pericarps and leaves. Furthermore, transgenic verification and dynamic cytological observation reveal that overexpressed BnaA02.SE can promote silique elongation by regulating JA and IAA contents, affecting cell proliferation and expansion, respectively, and finally enhance seed yield by influencing SPS and TSW. Haplotype analysis reveal that the homologs of BnaA02.SE may also be involved in silique elongation regulation. Our findings provided comprehensive insights into a newly SEL trait, and cloned the first gene (BnaA02.SE) controlling silique elongation in B. napus. The identified BnaA02.SE and its homologs can offer a valuable target for improving B. napus yield. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Primary HCO is a rare, aggressive ovarian malignant tumor, morphologically resembling HCC. SALL4 can be adopted to differentiate HCO from HCC. The serum AFP and CA125 rather than HE4 can be employed as possible biomarkers to track treatment and monitor recurrence. We report a case of a postmenopausal woman presenting with lower abdominal pain and vaginal bleeding. She went through a maximal debulking surgery, and the pathological biopsy revealed hepatoid carcinoma of the ovary (HCO). Immunohistochemical assay demonstrates SALL4 as an indicator to differentiate HCO from hepatocellular carcinoma (HCC). [ABSTRACT FROM AUTHOR]

SUMMARY: Brassica napus is an important oil crop and an allotetraploid species. However, the detailed analysis of gene function and homoeologous gene expression in all tissues at different developmental stages was not explored. In this study, we performed a global transcriptome analysis of 24 vegetative and reproductive tissues at six developmental stages (totally 111 tissues). These samples were clustered into eight groups. The gene functions of silique pericarp were similar to roots, stems and leaves. In particular, glucosinolate metabolic process was associated with root and silique pericarp. Genes involved in protein phosphorylation were often associated with stamen, anther and the early developmental stage of seeds. Transcription factor (TF) genes were more specific than structural genes. A total of 17 100 genes that were preferentially expressed in one tissue (tissue‐preferred genes, TPGs), including 889 TFs (5.2%), were identified in the 24 tissues. Some TPGs were identified as hub genes in the co‐expression network analysis, and some TPGs in different tissues were involved in different hormone pathways. About 67.0% of the homoeologs showed balanced expression, whereas biased expression of homoeologs was associated with structural divergence. In addition, the spatiotemporal expression of homoeologs was related to the presence of transposable elements (TEs) and regulatory elements (REs); more TEs and fewer REs in the promoters resulted in divergent expression in different tissues. This study provides a valuable transcriptional map for understanding the growth and development of B. napus, for identifying important genes for future crop improvement, and for exploring gene expression patterns in the B. napus. [ABSTRACT FROM AUTHOR]

The petal colour of rapeseed plants is usually yellow but can range from milky white to orange or pink, making petal colour a popular target in rapeseed breeding programmes. In this study, metabolites and RNA were extracted from the yellow (Bn‐Y) and orange (Bn‐O) petal colour lines in rapeseed. Chromatography analysis, RNA‐Seq and quantitative RT‐PCR analysis were conducted. A total of 89 differential metabolites including 64 down‐regulated and 25 up‐regulated metabolites were identified in the petals of orange versus yellow rapeseed by UHPLC‐ESI‐MS/MS. A total of 168 differentially expressed genes (DEGs) were detected in the petals of Bn‐O versus Bn‐Y plants. KEGG functional annotation and quantitative RT‐PCR analysis showed that BnaC08g39510D and BnaA09g10680D expression was significantly higher in orange petals than in yellow and that BnaC09g07880D and BnaC09g08690D were strongly expressed in yellow petals but were not expressed in orange petals. These results will be useful for further understanding the molecular mechanisms underlying petal colour and provide the theoretical and practical basis for breeding varieties with colourful petals. [ABSTRACT FROM AUTHOR]

Ferulate‐5‐hydroxylase is a key enzyme involved in the conversion of the guaiacyl monolignol to the syringyl monolignol in angiosperms. The monolignol ratio has been proposed to affect biomass recalcitrance and the resistance to plant disease. Stem rot caused by the fungus Sclerotinia sclerotiorum in Brassica napus causes severe losses in its production. To date, there is no information about the effect of the lignin monomer ratio on the resistance to S. sclerotiorum in B. napus. Four dominantly expressed ferulate‐5‐hydroxylase genes were concertedly knocked out by CRISPR/Cas9 in B. napus, and three mutant lines were generated. The S/G lignin compositional ratio was decreased compared to that of the wild type based on the results of Mӓule staining and 2D‐NMR profiling in KO‐7. The resistance to S. sclerotiorum in stems and leaves increased for the three f5h mutant lines compared with WT. Furthermore, we found that the stem strength of f5h mutant lines was significantly increased. Overall, we demonstrate for the first time that decreasing the S/G ratio by knocking out of the F5H gene improves S. sclerotiorum resistance in B. napus and increases stem strength. The oilseed rape production is unremittingly affected by Sclerotinia sclerotiorum, which causes stem and leaf rot and reduces the production of rapeseed oil. Lignin is an established physical barrier against pathogens, and the different lignin monomer G and S content can have different lignin structures. In this study, four dominantly expressed BnF5H genes were knocked out by CRISPR/Cas9 simultaneously in B. napus, and the f5h mutants were generated. The S‐/G‐lignin composition ratio was decreased compared to that of the wild type (WT) based on the results of Mӓule staining and 2D‐NMR profiling in the KO‐7 line. The resistance to S. sclerotiorum in stems and leaves increased in knock‐out lines. Furthermore, we found that the stem strength of mutants was significantly increased compared to that of the WT. Collectively, for the first time, we demonstrate that knockout of the lignin pathway gene F5H decreases the S/G ratio, improves S. sclerotiorum resistance in B. napus, and increases stem strength. [ABSTRACT FROM AUTHOR]

Rapeseed (Brassica napus L.) is the second most important oilseed crop in edible vegetable oil and bioenergy; however, drought stress generally causes a decrease in rapeseed yield and oil content, especially during the reproductive stage. In our study, we measured the oil and protein contents and gibberellic acid (GA) and abscisic acid (ABA) levels in seeds that were acquired on the 30th, 40th, and 50th days after flowering under control and drought treatments. RNA and protein libraries were constructed from the stressed seeds to perform transcriptome and proteome analyses, respectively. Our results demonstrated that the oil content decreased due to four primary mechanisms: downregulation of fatty acid biosynthesis‐associated genes and proteins; upregulation of fatty acid degradation‐associated genes and proteins; enhancement of protein storage due to changes in the abundances of relevant genes and proteins; and upregulation of Gly‐Asp‐Ser‐Leu (GDSL) gene expression, potentially as the result of upregulating the GA biosynthesis gene GA20ox3 and downregulating the GA inactivating gene GA2ox3 and thus an increase in GA content. During seed maturation, oil storage change may also relate to increasing ABA content as the upregulation of two members of NCED6 (9‐cis‐epoxycarotenoid dioxygenase) gene family involved in ABA biosynthesis, and the upregulation of genes involved in ABA signal transduction. These results will help to establish a foundation for breeding excellent varieties of rapeseed with high oil content for areas with frequent droughts to promote the supply of edible vegetable oil and biofuel. [ABSTRACT FROM AUTHOR]

Differences in DNA methylation patterns might lead to differences in fruit maturation time in the citrus Satsuma, but the underlying mechanism is unclear. Here, we explored the differences in methylation patterns during fruit ripening in Satsuma among 20 early‐ and late‐maturing Satsuma varieties and compared DNA methylation patterns in two Satsuma cultivars (Ooita wase and Aoshima unshiu) at different developmental stages using methylation‐sensitive fragment length polymorphism (MSAP) analysis. We cloned and sequenced DNA from different bands to identify differentially methylated genes involved in fruit ripening. The internal methylation of CCGG sequences occurred more frequently in the early‐maturing Satsuma cultivars (8.47%) than the late‐maturing cultivars (6.74%), whereas the external methylation of CCGG sequences occurred less frequently in the early‐maturing cultivars (24.98%) compared to the late‐maturing types (27.27%). Genes encoding the G protein α subunit and zinc‐binding protein of the histidine triad (HIT) family and two unknown genes homologous to expressed sequence tag (EST) sequences (CX052976.1 and CX071135.1) were found to be modified by methylation during the fruit ripening process. These findings suggest that DNA methylation might play important roles in regulating fruit ripening in Satsuma. Our results lay the foundation for analysing the molecular mechanism underlying fruit ripening in this important citrus crop. [ABSTRACT FROM AUTHOR]

Glucosinolates are amino acid‐derived secondary metabolites that act as chemical defense agents against pests. However, the presence of high levels of glucosinolates severely diminishes the nutritional value of seed meals made from rapeseed (Brassica napus L.). To identify the loci affecting seed glucosinolate content (SGC), we conducted genome‐wide resequencing in a population of 307 diverse B. napus accessions from the three B. napus ecotype groups, namely, spring, winter, and semi‐winter. These resequencing data were used for a genome‐wide association study (GWAS) to identify the loci affecting SGC. In the three ecotype groups, four common and four ecotype‐specific haplotype blocks (HBs) were significantly associated with SGC. To identify candidate genes controlling SGC, transcriptome analysis was carried out in 36 accessions showing extreme SGC values. Analyses of haplotypes, genomic variation, and candidate gene expression pointed to five and three candidate genes in the common and spring group‐specific HBs, respectively. Our expression analyses demonstrated that additive effects of the three candidate genes in the spring group‐specific HB play important roles in the SGC of B. napus. [ABSTRACT FROM AUTHOR]

Allotetraploid oilseed rape ( Brassica napus L.) is an agriculturally important crop. Cultivation and breeding of B. napus by humans has resulted in numerous genetically diverse morphotypes with optimized agronomic traits and ecophysiological adaptation. To further understand the genetic basis of diversification and adaptation, we report a draft genome of an Asian semi-winter oilseed rape cultivar ' ZS11' and its comprehensive genomic comparison with the genomes of the winter-type cultivar 'Darmor- bzh' as well as two progenitors. The integrated BAC-to- BAC and whole-genome shotgun sequencing strategies were effective in the assembly of repetitive regions (especially young long terminal repeats) and resulted in a high-quality genome assembly of B. napus ' ZS11'. Within a short evolutionary period (~6700 years ago), semi-winter-type ' ZS11' and the winter-type 'Darmor- bzh' maintained highly genomic collinearity. Even so, certain genetic differences were also detected in two morphotypes. Relative to 'Darmor- bzh', both two subgenomes of ' ZS11' are closely related to its progenitors, and the ' ZS11' genome harbored several specific segmental homoeologous exchanges ( HEs). Furthermore, the semi-winter-type ' ZS11' underwent potential genomic introgressions with B. rapa (Ar). Some of these genetic differences were associated with key agronomic traits. A key gene of A03. FLC3 regulating vernalization-responsive flowering time in ' ZS11' was first experienced HE, and then underwent genomic introgression event with Ar, which potentially has led to genetic differences in controlling vernalization in the semi-winter types. Our observations improved our understanding of the genetic diversity of different B. napus morphotypes and the cultivation history of semi-winter oilseed rape in Asia. [ABSTRACT FROM AUTHOR]

Brassica napus is one of the most important oil crops in the world, and stem rot caused by the fungus Sclerotinia sclerotiorum results in major losses in yield and quality. To elucidate resistance genes and pathogenesis-related genes, genome-wide association analysis of 347 accessions was performed using the Illumina 60K Brassica SNP (single nucleotide polymorphism) array. In addition, the detached stem inoculation assay was used to select five highly resistant (R) and susceptible (S) B. napus lines, 48 h postinoculation with S. sclerotiorum for transcriptome sequencing. We identified 17 significant associations for stem resistance on chromosomes A8 and C6, five of which were on A8 and 12 on C6. The SNPs identified on A8 were located in a 409-kb haplotype block, and those on C6 were consistent with previous QTL mapping efforts. Transcriptome analysis suggested that S. sclerotiorum infection activates the immune system, sulphur metabolism, especially glutathione ( GSH) and glucosinolates in both R and S genotypes. Genes found to be specific to the R genotype related to the jasmonic acid pathway, lignin biosynthesis, defence response, signal transduction and encoding transcription factors. Twenty-four genes were identified in both the SNP-trait association and transcriptome sequencing analyses, including a tau class glutathione S-transferase ( GSTU) gene cluster. This study provides useful insight into the molecular mechanisms underlying the plant's response to S. sclerotiorum. [ABSTRACT FROM AUTHOR]

Background Wenxin Keli is a popular Chinese herb extract that approximately five million Asians are currently taking for the treatment of a variety of ventricular arrhythmias. However, its electrophysiological mechanisms remain poorly understood. Methods and results The concentration-dependent electrophysiological effects of Wenxin Keli were evaluated in the isolated rabbit left ventricular myocytes and wedge preparation. Wenxin Keli selectively inhibited late sodium current (INa) with an IC50 of 3.8 ± 0.4 mg/mL, which was significantly lower than the IC50 of 10.6 ± 0.9 mg/mL (n = 6, P < 0.05) for the fast INa. Wenxin Keli produced a small but statistically significant QT prolongation at 0.3 mg/mL, but shortened the QT and Tp-e interval at concentrations ≥1 mg/mL. Wenxin Keli increased QRS duration by 10.1% from 34.8 ± 1.0 ms to 38.3 ± 1.1 ms (n = 6, P < 0.01) at 3 mg/mL at a basic cycle length of 2,000 ms. However, its effect on the QRS duration exhibited weak use-dependency, that is, QRS remained less changed at increased pacing rates than other classic sodium channel blockers, such as flecainide, quinidine, and lidocaine. On the other hand, Wenxin Keli at 1-3 mg/mL markedly reduced dofetilide-induced QT and Tp-e prolongation by attenuation of its reverse use-dependence and abolished dofetilide-induced early afterdepolarization (EAD) in four of four left ventricular wedge preparations. It also suppressed digoxin-induced delayed afterdepolarization (DAD) and ventricular tachycardias without changing the positive staircase pattern in contractility at 1-3 mg/mL in a separate experimental series (four of four). Conclusions Wenxin Keli suppressed EADs, DADs, and triggered ventricular arrhythmias via selective inhibition of late INa. [ABSTRACT FROM AUTHOR]

With 2 figures and 2 tables Brassica rapa (AA), which has a high level of genetic diversity, has been used to widen the genetic base of oilseed rape (B. napus L., AACC). However, the differences in the degree to which the genetic base of oilseed rape can be widened using different forms of B. rapa have not been well characterized. We used a strategy of virtual allopolyploid to investigate the genetic differences between the A subgenome of natural oilseed rape and different ecotypes of B. rapa. In this strategy, the genetic characteristics of the virtual allopolyploid lines are deduced from the genotypes of the parental lines which are established using molecular markers, without the need for interspecific hybridization. Three genotypes of B. oleracea and 56 accessions of B. rapa which originated from Europe, China and India were genotyped using simple sequence repeat markers, together with nine oilseed rape lines representing spring, semi‐winter and winter types. The genotypes of 168 virtual allopolyploid lines were derived from those of the parental lines and compared with those of the natural oilseed rape lines. Our data revealed that the virtual allopolyploid lines that were derived from Chinese semi‐winter B. rapa showed substantial genetic variation from natural oilseed rape. This indicates that Chinese semi‐winter B. rapa can be used effectively to broaden the germplasm of oilseed rape. [ABSTRACT FROM AUTHOR]

With 2 figures and 1 table Abstract Brassica species are important industrial materials. Recently, simple sequence repeat (SSR) markers have become preferred molecular markers because of their simplicity, high levels of polymorphism and codominant nature. Numerous SSR markers have been developed in Brassica crops, but not every SSR marker has an equal value, and they must be tested individually for each application. To develop a set of standardized, highly efficient core SSR primers, we screened 190 primer pairs from among over 2353 SSR primer pairs that have been mapped for Brassica species. Ten different primer pairs were selected for each of the 19 linkage groups that corresponded with the chromosomes of Brassica genomes A and C. We also established 19 multiplex polymerase chain reaction (PCR) combinations, one per linkage group. Twenty accessions from six Brassica species were used to test these primer combinations, and an average of 15 clear bands were amplified successfully in each reaction. It is clear that multiplex PCR is a practical method for germplasm identification, genetic diversity analysis and backcross breeding in Brassica crops. [ABSTRACT FROM AUTHOR]