BjuA03.BNT1 plays a positive role in resistance to clubroot disease in resynthesized Brassica juncea L.

Clubroot has become a major obstacle in rapeseed production. Breeding varieties resistant to clubroot is the most effective method for disease management. However, the clubroot-resistant germplasm of rapeseed remains limited. To tackle this challenge, we synthesized the clubroot-resistant mustard, CT19, via distant hybridization, and subsequently an F2 segregating population was created by intercrossing CT19 with a clubroot-susceptible germplasm CS15. A major-effect clubroot resistance QTL qCRa3-1 on chromosome A03 was identified through QTL scanning. Transcriptome analyses of CT19 and CS15 revealed that the mechanisms conferring resistance to Plasmodiophora brassica likely involved the regulation of flavonoid metabolism, fatty acid metabolism, and sulfur metabolism. By combining the results from transcriptome, QTL mapping, and gene sequencing, a candidate gene BjuA03.BNT1, encoding NLR (nucleotide-binding domain leucine-rich repeat-containing receptors) protein, was obtained. Intriguingly, comparing with CT19, a base T insertion was discovered in the BjuA03.BNT1 gene's coding sequence in CS15, resulting an alteration within the LRR conserved domain. Overexpression of BjuA03.BNT1 from CT19 notably enhanced the resistance to clubroot in Arabidopsis. Our investigations revealed that BjuA03.BNT1 regulated the resistance to clubroot by modulating fatty acid synthesis and the structure of cell wall. These results are highly relevant for molecular breeding to improve clubroot resistance in rapeseed.

The B-box transcription factor BnBBX22.A07 enhances salt stress tolerance by indirectly activating BnWRKY33.C03.

Salt stress has a detrimental impact on both plant growth and global crop yields. B-box proteins have emerged as pivotal players in plant growth and development regulation. Although the precise role of B-box proteins orchestrating salt stress responses in B. napus (Brassica napus) is not well understood in the current literature, further research and molecular explorations are required. Here, we isolated the B-box protein BnBBX22.A07 from B. napus. The overexpression of BnBBX22.A07 significantly improved the salt tolerance of Arabidopsis (Arabidopsis thaliana) and B. napus. Transcriptomic and histological analysis showed that BnBBX22.A07 enhanced the salt tolerance of B. napus by activating the expression of reactive oxygen species (ROS) scavenging-related genes and decreasing salt-induced superoxide anions and hydrogen peroxide. Moreover, BnBBX22.A07 interacted with BnHY5.C09, which specifically bound to and activated the promoter of BnWRKY33.C03. The presence of BnBBX22.A07 enhanced the activation of BnHY5.C09 on BnWRKY33.C03. Overexpression of BnHY5.C09 and BnWRKY33.C03 improved the salt tolerance of Arabidopsis. Functional analyses revealed that BnBBX22.A07-mediated salt tolerance was partly dependent on WRKY33. Taken together, we demonstrate that BnBBX22.A07 functions positively in salt responses not only by activating ROS scavenging-related genes but also by indirectly activating BnWRKY33.C03. Notably, our study offers a promising avenue for the identification of candidate genes that could be harnessed in breeding endeavours to develop salt-resistant transgenic crops.

Population Genomics analysis of Leptosphaeria biglobosa Associated with Brassica napus in China Reveals That Geographical Distribution Influences Its Genetic Polymorphism.

Blackleg disease, a major threat to Brassica crops worldwide, is primarily caused by the pathogen Leptosphaeria biglobosa. Investigating the genetic variation of L. biglobosa is crucial for managing and preventing the disease in Brassica napus. To date, there is scarce genomic variation information available for populations of L. biglobosa in China. In this study, 73 L. biglobosa strains of canola stalks were collected from 12 provinces in China and subjected to re-sequencing. The 73 assemblies averaged 1340 contigs, 72,123 bp N50, and 30.17 Mb in size. In total, 9409 core orthogroups and 867 accessory orthogroups were identified. A total of 727,724 mutation loci were identified, including 695,230 SNPs and 32,494 indels. Principal component analysis (PCA) and population structure analysis showed that these strains could be divided into seven subgroups. The strains in most provinces were clustered into a single subgroup, suggesting a strong influence of the geographic environment on strain variation. The average nucleotide diversity (θπ) of all strains was 1.03 × 10-3, indicating important genetic diversity among strains from different regions of China. This study provides valuable resources for future comparative genomics, gives new insights into the population evolution of L. biglobosa, and supports the development of strategies for managing blackleg disease in canola.

CCL2 regulated by the CTBP1-AS2/miR-335-5p axis promotes hemangioma progression and angiogenesis.

CONTEXT: Hemangioma (HA) is a benign vascular neoplasm that can lead to permanent scarring. C-C motif chemokine ligand 2 (CCL2) plays a crucial role in facilitating growth and angiogenesis during HA progression. However, the mechanism regulating CCL2 in HA remains poorly elucidated. OBJECTIVE: To elucidate the mechanism regulating CCL2 in HA. METHODS: Quantitative real-time polymerase chain reaction (RT-qPCR) was employed to determine the expression levels of CCL2, long noncoding RNA (lncRNA) CTBP1 divergent transcript (CTBP1-AS2), and microRNAs (miRNAs). Proliferation, migration, invasion, and angiogenic abilities of human HA endothelial cells (HemECs) were assessed using cell counting kit-8 (CCK-8), colony formation, flow cytometry, transwell, and tube formation assays. Bioinformatics analysis, RNA pull-down, and luciferase reporter assays were conducted to investigate whether CCL2 targets miR-335-5p. Additionally, rescue experiments were performed in this study. RESULTS: CCL2 expression was markedly upregulated in HemECs. CCL2 promoted HA cell proliferation, migration, invasion, and angiogenesis while inhibiting apoptosis. CCL2 was directly targeted by miR-335-5p. Additionally, we found that CTBP1-AS2 could function as a competing endogenous RNA (ceRNA) to sponge miR-335-5p, thereby upregulating CCL2. CONCLUSION: Our findings suggest that targeting the CTBP1-AS2/miR-335-5p/CCL2 axis may hold promise as a therapeutic strategy for HA.

Comparative Transcriptomics Uncovers Upstream Factors Regulating BnFAD3 Expression and Affecting Linolenic Acid Biosynthesis in Yellow-Seeded Rapeseed (Brassica napus L.).

α-Linolenic acid (ALA) is an important nutrient component in rapeseed oil, and rapeseed breeders want to either restrain or enhance the function of fatty acid desaturases (FADs) in the ALA biosynthesis pathway. To determine the reason for the upregulation of rapeseed BnFAD genes in two high-ALA accessions, R8Q10 and YH25005, we compared their transcriptome profiles in the seed at 24 days after pollination (DAP) with those of two low-ALA lines, A28 and SW. The expression levels of twenty-eight important genes in the seed samples at 20, 27, and 34 DAP were also investigated using an RT-qPCR. The expression levels of genes involved in flavonoid and proanthocyanidin synthesis, including BnCHS, BnCHI, BnDFR, BnFLS1, BnLDOX, BnBAN, BnTT10, and BnTT12 and genes encoding the transcription factors BnTT1, BnTT2, BnTT8, and BnTT16 were lower in R8Q10 and YH25005 than in A28 and SW. The expression levels of genes encoding master transcription factors in embryo development, such as BnLEC1, BnABI3, BnFUS3, BnL1L, BnAREB3, and BnbZIP67, were elevated significantly in the two high-ALA accessions. Combined with previous results in the Arabidopsis and rapeseed literature, we speculated that the yellow-seededness genes could elevate the activity of BnLEC1, BnABI3, BnFUS3, and BnbZIP67, etc., by reducing the expression levels of several transparent testa homologs, resulting in BnFAD3 and BnFAD7 upregulation and the acceleration of ALA synthesis. Yellow-seededness is a favorable factor to promote ALA synthesis in the two high-ALA accessions with the yellow-seeded trait. These findings provide initial insights into the transcriptomic differences between high-/low-ALA germplasms and a theoretic basis for seed quality breeding.

Identification candidate genes for salt resistance through quantitative trait loci-sequencing in Brassica napus L.

Rapeseed (Brassica napus L.) is one of the most important oil crops worldwide. However, its yield is greatly limited by salt stress, one of the primary abiotic stresses. Identification of salt-tolerance genes and breeding salt-tolerant varieties is an effective approach to address this issue. Unfortunately, little is known about the salt-tolerance quantitative trait locus (QTL) and the identification of salt tolerance genes in rapeseed. In this study, high-throughput quantitative trait locus sequencing (QTL-seq) was applied to identifying salt-tolerant major QTLs based on two DNA pools from an F2:3 population of a cross between rapeseed line 2205 (salt tolerant) and 1423 (salt sensitive). A total of twelve major QTLs related to the salt tolerance rating (STR) were detected on chromosomes A03, A08, C02, C03, C04, C06, C07 and C09. To further enhance our understanding, we integrated QTL-seq data with transcriptome analysis of the two parental rapeseed plants subjected to salt stress, through which ten candidate genes for salt tolerance were identified within the major QTLs by gene differential expression, variation and annotated functions analysis. The marker SNP820 linked to salt tolerance was successfully validated and would be useful as a diagnostic marker in marker-assisted breeding. These findings provide valuable insights for future breeding programs aimed at developing rapeseed cultivars resistant to salt stresses.

Identification of Yellow Seed Color Genes Using Bulked Segregant RNA Sequencing in Brassica juncea L.

Yellow seed breeding is an effective method to improve oil yield and quality in rapeseed (Brassica napus L.). However, naturally occurring yellow-seeded genotypes have not been identified in B. napus. Mustard (Brassica juncea L.) has some natural, yellow-seeded germplasms, yet the molecular mechanism underlying this trait remains unclear. In this study, a BC9 population derived from the cross of yellow seed mustard "Wuqi" and brown seed mustard "Wugong" was used to analyze the candidate genes controlling the yellow seed color of B. juncea. Subsequently, yellow-seeded (BY) and brown-seeded (BB) bulks were constructed in the BC9 population and subjected to bulked segregant RNA sequencing (BSR-Seq). A total of 511 differentially expressed genes (DEGs) were identified between the brown and yellow seed bulks. Enrichment analysis revealed that these DEGs were involved in the phenylpropanoid biosynthetic process and flavonoid biosynthetic process, including key genes such as 4CL, C4H, LDOX/TT18, PAL1, PAL2, PAL4, TT10, TT12, TT4, TT8, BAN, DFR/TT3, F3H/TT6, TT19, and CHI/TT5. In addition, 111,540 credible single-nucleotide polymorphisms (SNPs) and 86,319 INDELs were obtained and used for quantitative trait locus (QTL) identification. Subsequently, two significant QTLs on chromosome A09, namely, qSCA09-3 and qSCA09-7, were identified by G' analysis, and five DEGs (BjuA09PAL2, BjuA09TT5, BjuA09TT6, BjuA09TT4, BjuA09TT3) involved in the flavonoid pathway were identified as hub genes based on the protein-to-protein network. Among these five genes, only BjuA09PAL2 and BjuA09F3H had SNPs between BY and BB bulks. Interestingly, the majority of SNPs in BjuA09PAL2 were consistent with the SNPs identified between the high-quality assembled B. juncea reference genome "T84-66" (brown-seed) and "AU213" (yellow-seed). Therefore, BjuA09PAL2, which encodes phenylalanine lyase, was considered as the candidate gene associated with yellow seed color of B. juncea. The identification of a novel gene associated with the yellow seed coloration of B. juncea through this study may play a significant role in enhancing yellow seed breeding in rapeseed.

Widely untargeted metabolomic profiling unearths metabolites and pathways involved in leaf senescence and N remobilization in spring-cultivated wheat under different N regimes.

Progression of leaf senescence consists of both degenerative and nutrient recycling processes in crops including wheat. However, the levels of metabolites in flag leaves in spring-cultivated wheat, as well as biosynthetic pathways involved under different nitrogen fertilization regimes, are largely unknown. Therefore, the present study employed a widely untargeted metabolomic profiling strategy to identify metabolites and biosynthetic pathways that could be used in a wheat improvement program aimed at manipulating the rate and onset of senescence by handling spring wheat (Dingxi 38) flag leaves sampled from no-, low-, and high-nitrogen (N) conditions (designated Groups 1, 2, and 3, respectively) across three sampling times: anthesis, grain filling, and end grain filling stages. Through ultrahigh-performance liquid chromatography-tandem mass spectrometry, a total of 826 metabolites comprising 107 flavonoids, 51 phenol lipids, 37 fatty acyls, 37 organooxygen compounds, 31 steroids and steroid derivatives, 18 phenols, and several unknown compounds were detected. Upon the application of the stringent screening criteria for differentially accumulated metabolites (DAMs), 28 and 23 metabolites were differentially accumulated in Group 1_vs_Group 2 and Group 1_vs_Group 3, respectively. From these, 1-O-Caffeoylglucose, Rhoifolin, Eurycomalactone;Ingenol, 4-Methoxyphenyl beta-D-glucopyranoside, and Baldrinal were detected as core conserved DAMs among the three groups with all accumulated higher in Group 1 than in the other two groups. Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that tropane, piperidine, and pyridine alkaloid biosynthesis; acarbose and validamycin biosynthesis; lysine degradation; and biosynthesis of alkaloids derived from ornithine, lysine, and nicotinic acid pathways were the most significantly (p < 0.05) enriched in Group 1_vs_Group 2, while flavone and flavonol as well as anthocyanins biosynthetic pathways were the most significantly (p < 0.05) enriched in Group 1_vs_Group 3. The results from this study provide a foundation for the manipulation of the onset and rate of leaf senescence and N remobilization in wheat.

Discovery of common loci and candidate genes for controlling salt-alkali tolerance and yield-related traits in Brassica napus L.

KEY MESSAGE: Common loci and candidate genes for controlling salt-alkali tolerance and yield-related traits were identified in Brassica napus combining QTL mapping with transcriptome under salt and alkaline stresses. The yield of rapeseed (Brassica napus L.) is determined by multiple yield-related traits, which are susceptible to environmental factors. Many yield-related quantitative trait loci (QTLs) have been reported in Brassica napus; however, no studies have been conducted to investigate both salt-alkali tolerance and yield-related traits simultaneously. Here, specific-locus amplified fragment sequencing (SLAF-seq) technologies were utilized to map the QTLs for salt-alkali tolerance and yield-related traits. A total of 65 QTLs were identified, including 30 QTLs for salt-alkali tolerance traits and 35 QTLs for yield-related traits, accounting for 7.61-27.84% of the total phenotypic variations. Among these QTLs, 18 unique QTLs controlling two to four traits were identified by meta-analysis. Six novel and unique QTLs were detected for salt-alkali tolerance traits. By comparing these unique QTLs for salt-alkali tolerance traits with those previously reported QTLs for yield-related traits, seven co-localized chromosomal regions were identified on A09 and A10. Combining QTL mapping with transcriptome of two parents under salt and alkaline stresses, thirteen genes were identified as the candidates controlling both salt-alkali tolerance and yield. These findings provide useful information for future breeding of high-yield cultivars resistant to alkaline and salt stresses.

Genome-Wide Association Studies of Salt Tolerance at the Seed Germination Stage and Yield-Related Traits in Brassica napus L.

Salt stress severely affects crop growth and development and reduces the yield of Brassica napus. Exploring natural genetic variations for high salt tolerance in B. napus seedlings is an effective approach to improve productivity under salt stress. Using 10,658 high-quality single nucleotide polymorphic (SNP) markers developed by specific-locus amplified fragment sequencing (SLAF-seq) technology, genome-wide association studies (GWAS) were performed to investigate the genetic basis of salt tolerance and yield-related traits of B. napus. The results revealed that 77 and 497 SNPs were significantly associated with salt tolerance and yield-related traits, of which 40 and 58 SNPs were located in previously reported QTLs/SNPs, respectively. We identified nineteen candidate genes orthologous with Arabidopsis genes known to be associated with salt tolerance and seven potential candidates controlling both salt tolerance and yield. Our study provides a novel genetic resource for the breeding of high-yield cultivars resistant to salt stress.

Microscopic and Transcriptomic Comparison of Powdery Mildew Resistance in the Progenies of Brassica carinata × B. napus.

Powdery mildew is a widespread disease in rapeseed due to a lack of resistant germplasm. We compared the foliar epidermal features and transcriptomic responses between the resistant (R) and susceptible (S) plants among the two parents and progenies of Brassica carinata × B. napus. The amount of cuticular wax and callose deposition on the R plants was much lower than that on the S plants; hence, these chemicals are not all essential to pre-penetration resistance, although the cuticular wax on the R plants had more needle-like crystals. A total of 1049 genes involved in various defense responses were expressed differentially among the R/S plants. The expression levels of two well-known susceptibility genes, MLO6 and MLO12, were much lower in the R plant, indicating an important role in PM resistance. A set of genes related to wax biosynthesis (KCS6, LACS2, CER and MAH1), cell wall modification (PMR5, PMEI9, RWA2, PDCB1 and C/VIF2), chloroplast function (Chlorophyllase-1, OEP161, PSBO1, CP29B and CSP41b), receptor kinase activity (ERECTA, BAK1, BAM2, LYM1, LYM3, RLK902, RLP11, ERL1 and ERL2), IPCS2, GF14 lambda, RPS4 and RPS6 were highly expressed in the R plants. In the S plants, most highly expressed genes were involved in later defense responses, including CERK1, LYK4, LIK1, NIMIN-1, CHITINASE 10, PECTINESTERASE, CYP81F2 and RBOHF and the genes involved in salicylic acid-dependent systemic acquired resistance and hypersensitive responses, indicating the occurrence of severe fungal infection. The results indicate that some uncertain pre-penetration defenses are pivotal for high resistance, while post-penetration defenses are more important for the S plant survival.

Bacterial Diversity and Potential Functions in Response to Long-Term Nitrogen Fertilizer on the Semiarid Loess Plateau.

Bacterial diversity and its functions are essential to soil health. N fertilization changes bacterial communities and interferes with the soil biogeochemical N cycle. In this study, bacterial community and soil physicochemical properties were studied in 2018 after applying N fertilizers (0, 52.5, 105, 157.5, and 210 kg N ha-1) for a long (2003-2018) and a short (2003-2004) duration in a wheat field on the Loess Plateau of China. Soil bacteria were determined using 16S rRNA Illumina-MiSeq®, and the prediction function was analyzed through PICRUSt. The study showed that N fertilizer significantly changed the diversity and abundance of bacterial communities. The phyla Proteobacteria, Actinobacteria, Acidobacteria, and Chloroflexi were most abundant, accounting for 74-80% of the bacterial community abundance. The optimum rates of N fertilizer application (N105) maintain soil health by promoting soil microbial diversity and abundance. The bacterial population abundance was higher after short-term N application than after N application for a long duration and lowest with the high N-fertilizer treatment (N210). High N enrichment led to more heterotrophic N-fixing microorganisms (Alphaproteobacteria), in which metabolism and genetic information processing dominated, while cellular processes, genetic information processing, metabolism, and organismal systems were the main functional categories under low N. The phyla Gemmatimonadetes, Actinobacteria, Bacteroidetes, and Chloroflexi were the key bacteria in the co-occurrence network. The genus Saccharimonadales of the superphylum Patescibacteria has a more significant impact under low N treatment. Long-term N fertilization affected the soil pH, NO3-N, and other physicochemical properties, and soil NO3-N was the highest indicator, contributing 81% of the bacterial community function under different N fertilizer treatments.

Identification of Alkaline Salt Tolerance Genes in Brassica napus L. by Transcriptome Analysis.

Soil salt alkalization is one major abiotic factor reducing the productivity of crops, including rapeseed, an indispensable oil crop and vegetable. The mechanism studies of alkali salt tolerance can help breed highly resistant varieties. In the current study, rapeseed (B. napus) line 2205 exhibited more tolerance to alkaline salt than line 1423 did. In line 2205, the lesser plasma membrane damage index, the accumulated osmotic solute, and higher antioxidant enzyme activities contributed to alkaline tolerance. A more integrated mesophyll-cell structure was revealed under alkali salt stress by ultrastructure observation in line 2205, which also implied a lesser injury. Transcriptome analysis showed that more genes responded to alkaline salt in line 2205. The expression of specific-response genes in line 1423 was lower than in line 2205. However, most of the specific-response genes in line 2205 had higher expression, which was mainly enriched in carbohydrate metabolism, photosynthetic processes, ROS regulating, and response to salt stress. It can be seen that the tolerance to alkaline salt is attributed to the high expression of some genes in these pathways. Based on these, twelve cross-differentially expressed genes were proposed as candidates. They provide clues for further analysis of the resistance mechanism of rapeseed.

Ethylene Plays a Dual Role during Infection by Plasmodiophora brassicae of Arabidopsis thaliana.

Plasmodiophora brassicae infection leads to hypertrophy of host roots and subsequent formation of galls, causing huge economic losses to agricultural producers of Cruciferae plants. Ethylene (ET) has been reported to play a vital role against necrotrophic pathogens in the classic immunity system. More clues suggested that the defense to pathogens in roots may be different from the acrial. The ET pathway may play a positive role in the infection of P. brassicae, as shown by recent transcriptome profiling. However, the molecular basis of ET remains poorly understood. In this study, we investigated the potential role of ethylene against P. brassicae infection in an ein3/eil1 double-mutant of Arabidopsis thaliana (A. thaliana). After infection, ein3/eil1 (Disease Index/DI: 93) showed more susceptibility compared with wild type (DI: 75). Then, we inoculated A. thaliana Columbia-0 (Col-0) with P. brassicae by 1-aminocyclopropane-1-carboxylic acid (ACC) and pyrazinamide (PZA), respectively. It was found that the symptoms of infected roots with ACC were more serious than those with PZA at 20 dpi (day post infection). However, the DI were almost the same in different treatments at 30 dpi. WRKY75 can be directly regulated by ET and was upregulated at 7 dpi with ACC, as shown by qRT-PCR. The wrky75-c mutant of A. thaliana (DI: 93.75) was more susceptible than the wild type in Arabidopsis. Thus, our work reveals the dual roles of ET in infection of P. brassicae and provides evidence of ET in root defense against pathogens.

Changes in Ammonia-Oxidizing Archaea and Bacterial Communities and Soil Nitrogen Dynamics in Response to Long-Term Nitrogen Fertilization.

Ammonia oxidizing archaea (AOA) and bacteria (AOB) mediate a crucial step in nitrogen (N) metabolism. The effect of N fertilizer rates on AOA and AOB communities is less studied in the wheat-fallow system from semi-arid areas. Based on a 17-year wheat field experiment, we explored the effect of five N fertilizer rates (0, 52.5, 105, 157.5, and 210 kg ha-1 yr-1) on the AOA and AOB community composition. This study showed that the grain yield of wheat reached the maximum at 105 kg N ha-1 (49% higher than control), and no further significant increase was observed at higher N rates. With the increase of N, AOA abundance decreased in a regular trend from 4.88 × 107 to 1.05 × 107 copies g-1 dry soil, while AOB abundance increased from 3.63 × 107 up to a maximum of 8.24 × 107 copies g-1 dry soil with the N105 treatment (105 kg N ha-1 yr-1). Application rates of N fertilizer had a more significant impact on the AOB diversity than on AOA diversity, and the highest AOB diversity was found under the N105 treatment in this weak alkaline soil. The predominant phyla of AOA and AOB were Thaumarchaeota and Proteobacteria, respectively, and higher N treatment (N210) resulted in a significant decrease in the relative abundance of genus Nitrosospira. In addition, AOA and AOB communities were significantly associated with grain yield of wheat, soil potential nitrification activity (PNA), and some soil physicochemical parameters such as pH, NH4-N, and NO3-N. Among them, soil moisture was the most influential edaphic factor for structuring the AOA community and NH4-N for the AOB community. Overall, 105 kg N ha-1 yr-1 was optimum for the AOB community and wheat yield in the semi-arid area.

Transcriptome profiling reveals major structural genes, transcription factors and biosynthetic pathways involved in leaf senescence and nitrogen remobilization in rainfed spring wheat under different nitrogen fertilization rates.

The present study was undertaken to profile transcriptional changes in flag leaves between anthesis and end of grain filling stages of rainfed spring wheat cultivar under varying nitrogen (N) application rates: 0 kg/ha (NN), 52.5 kg/ha (LN), and 210 kg/ha (HN). A total of 4485 and 4627 differentially expressed genes (DEGs) were detected in LN and HN, respectively. The differential application of N altered several pathways; including plant hormone signal transduction, mitogen-activated protein kinase signaling pathway-plant, photosynthesis, phenylpropanoid biosynthesis and ATP-binding cassette transporters. Jasmonic acid, abscisic acid, salicylic acid and brassinosteroid related genes promoted leaf senescence in NN or LN, whereas auxin, gibberellin acid and cytokinins genes inhibited leaf senescence in HN. Major transcription factors: auxin/indole-3-acetic acid (AUX/IAA), no apical meristem (NAC) and WRKY expressed higher in either HN or LN than NN. The DEGs, pathways and transcription factors provide valuable insight for manipulation of leaf senescence and N remobilization in wheat.

E2F1-Induced lncRNA BAIAP2-AS1 Overexpression Contributes to the Malignant Progression of Hepatocellular Carcinoma via miR-361-3p/SOX4 Axis.

Currently, plenty of researches have revealed that long noncoding RNAs (lncRNAs) can act as crucial roles during the progression of various tumors, including hepatocellular carcinoma (HCC). Here, we measured the expression of lncRNA BAIAP2 antisense RNA 1(BAIAP2-AS1) as well as its contribution to the developments of HCC. In this study, the expressions of BAIAP2-AS1 and SOX4 were distinctly upregulated in HCC cells and tissues, and high BAIAP2-AS1 may be a novel biomarker for HCC. E2F1 activated BAIAP2-AS1 expression. The silence of BAIAP2-AS1 inhibited the proliferation and metastasis of HepG2 and PLC5 cells. Assays for relationship verification showed that BAIAP2-AS1 regulated the expression of SOX4 and miR-361-3p. Rescue experiments further confirmed the positive interaction between miR-361-3p and BAIAP2-AS1 as well as between miR-361-3p and SOX4. Overall, BAIAP2-AS1 modulated the miR-361-3p/SOX4 axis to promote the development of HCC. Thus, our study offers a potential therapeutic target for treating HCC.

Complete Genome Sequence of Escherichia coli Strain FEX669, a ColV Plasmid-Containing Isolate from Retail Chicken Meat.

Escherichia coli strain FEX669 was isolated from retail ground chicken and shown to contain the extraintestinal pathogenic E. coli (ExPEC) virulence genes sfaD, focC, and iutA Because this presumptive ExPEC strain was isolated from a retail food item and it was a weak biofilm former, it was characterized using whole-genome sequencing using the PacBio RS II platform. Genomic analysis showed that the FEX669 chromosome is 4,973,943 bp long, with a GC content of 50.47%, and is accompanied by a ColV plasmid that is 237,102 bp long, with a GC content of 50.49%.

Towards breeding of rapeseed (Brassica napus) with alien cytoplasm and powdery mildew resistance from Ethiopian mustard (Brassica carinata).

Powdery mildew (PM), caused by Erysiphe cruciferarum, is an epidemic of oil rapeseed (Brassica napus L.) growing worldwide, but PM resistant germplasm is rare in this species. We screened 102 accessions of B. napus and other cruciferous species and found an Ethiopian mustard (Brassica carinata) cultivar 'White flower' immune to PM in both the field and greenhouse. Outcrossing in the female parent 'White flower' was promoted by using a chemical gametocide tribenuron-methyl, to obtain hybrid seeds of distant hybridization with an elite B. napus cultivar 'Zhongshuang11'. Three true F1 hybrids with B. carinata cytoplasm were obtained without using embryo rescue, which showed complete male sterility and light yellow petals. The hybrid plants and the progenies derived from backcrossing were validated using morphological traits, seed quality, and molecular markers. Five lines in the BC1F3 generation, named 'W7-1', 'W7-4', 'W7-6', 'W8-1', and 'W8-3', and one BC2F2 line 'W3PS-1', whose young leaf was yellow green, were identified to be resistant or moderately resistant to PM. The seed quality and some morphological traits of these lines resembled the parent 'Zhongshuang11', indicating that the resistance gene(s) has been preliminarily introduced into B. napus.

Evaluation of a hybrid in-field sampling method for the detection of pathogenic bacteria through consideration of a priori knowledge of factors related to non-random contamination.

Pre-harvest testing is increasingly used to enhance the microbial safety of fresh produce. Traditional sampling assumes that sample collectors have no information on potential contamination sources. Knowledge of such factors could potentially increase the effectiveness of pre-harvest sampling programs. Simulation modeling and field validation trials were used to evaluate a hybrid "Samples of Opportunity" (SOO) sampling method that included a portion of the samples based on the sampler's knowledge of risk factors in pre-harvest produce fields. Relative effectiveness of SOO sampling was compared with three traditional sampling methods. These evaluations were based on three non-random contamination scenarios. The mean detection probability of SOO is 96% higher than traditional sampling methods (p < 0.001). However, if the site of actual contamination is offset from assumed area of contamination, the detection probability of SOO sampling drops, and becomes similar or even worse than that achieved by the other sampling methods. Preliminary field validation trials indicated indeed that SOO performed better than the other three sampling methods. This study provides a mathematical approach for evaluating the effectiveness of four pre-harvest sampling methods, and suggests that having a priori knowledge of the contamination source in the field would improve effectiveness of sampling, particularly if done using a standardized protocol.