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Herein, we reported the transfer of donor-derived antihuman leukocyte antigen (HLA) antibodies in 2 recipients after lung transplantation. Case 1: A 39-year-old woman with pleuroparenchymal fibroelastosis underwent a single brain-dead donor lung transplantation. Antibody screening 36 days after transplantation demonstrated high levels of de novo nondonor HLA class I-specific antibodies. The antibody screening in the donor serum revealed that the donor demonstrated a largely overlapping antibody profile. Importantly, the donor serum also included high-level HLA-specific antibodies against the recipient HLA-specific antigens, which were not detected in the recipient sera after transplantation. Donor-derived anti-HLA antibodies were still detected in the recipient 39 months after transplantation, without causing any complications such as graft-vs-host disease. Case 2: A 47-year-old woman underwent living-donor lobar lung transplantation for pulmonary complications after bone marrow transplantation with a right lower lobe from her husband and the left lower lobe from her sister. On postoperative day 39, the recipient's anti-HLA-class I antibody profile was found to be similar to that of the highly sensitized left lung donor. These donor-derived anti-HLA antibodies remained to be produced in the recipient 66 months after transplantation, without the development of complications.

Brassica rapa L., which includes Chinese cabbage, turnip, and pak choi, has more complex flowering time regulation than does Arabidopsis thaliana due to the presence of multiple paralogous flowering time genes. FLOWERING LOCUS C (FLC) is one of the key genes regulating flowering time. Although there is a single gene in A. thaliana, there are four FLC paralogs in B. rapa. BrFLC1, BrFLC2, and BrFLC3 are involved in regulating flowering time, whereas BrFLC5 is deemed a pseudogene because of a mutation (from G to A) in the splice site of the third intron. However, some accessions do not have this mutation, and a flowering-time quantitative trait locus (QTL) covering BrFLC5 associated with late flowering has been identified, suggesting that some accessions in B. rapa have a functional BrFLC5 gene. However, it has not been shown whether BrFLC5 acts as a floral repressor. To examine the allelic variation of BrFLC5, we genotyped 310 B. rapa accessions and found 19 had homozygous and 81 had heterozygous putative functional BrFLC5 alleles. BrFLC5 acts as a floral repressor when overexpressed in A. thaliana. Variation in the BrFLC5 expression level in pre-vernalized plants was identified and this transcriptional variation was not associated with the G/A polymorphism in the third intron. However, higher BrFLC5 expression in pre-vernalized plants is associated with 584 bp insertion in the promoter region. The possibility that a high expression of a functional BrFLC5 could contribute to producing premature bolting-resistant lines in B. rapa vegetables is discussed.

Cabbage (Brassica oleracea var. capitata) Fusarium wilt (CFW) is a disease that poses a critical threat to global cabbage production. Screening for resistant resources in order to support the breeding of resistant cultivars is the most reliable approach to control this disease. CFW is caused by Fusarium oxysporum f. sp. conglutinans (Foc), which consists of two physiological races (race 1 and 2). While many studies have focused on resistance screening, gene mining, and inheritance-based research associated with resistance to Foc race 1, there have been few studies specifically analyzing resistance to Foc race 2, which is a potential threat that can overcome type A resistance. Here, 166 cabbage resources collected from around the world were evaluated for the resistance to both Foc races, with 46.99% and 38.55% of these cabbage lines being resistant to Foc race 1 and race 2, respectively, whereas 33.74% and 48.80% were susceptible to these two respective races. Of these 166 analyzed cabbage lines, 114 (68.67%) were found to be more susceptible to race 2 than to race 1, and 28 of them were resistant to race 1 while susceptible to race 2, underscoring the highly aggressive nature of Foc race 2. To analyze the inheritance of Foc race 2 resistance, segregated populations derived from the resistant parental line ‘Badger Inbred 16’ and the susceptible one ‘01-20’ were analyzed with a major gene plus polygene mixed genetic model. The results of this analysis revealed Foc race 2-specific resistance to be under the control of two pairs of additive-dominant-epistatic major genes plus multiple additive-dominant-epistatic genes (model E). The heritability of these major genes in the BC1P1, BC1P2, and F2 generations were 32.14%, 72.80%, and 70.64%, respectively. In summary, these results may aid in future gene mining and breeding of novel CFW-resistant cabbage cultivars.

Tuberous stem of kohlrabi is an important agronomic trait, however, the molecular basis of tuberization is poorly understood. To elucidate the tuberization mechanism, we conducted a comparative transcriptomic analysis between kohlrabi and broccoli at 10 and 20 days after germination (DAG) as tuberous stem initiated between these time points. A total of 5580 and 2866 differentially expressed transcripts (DETs) were identified between genotypes (kohlrabi vs. broccoli) and growth stages (10 DAG vs. 20 DAG), respectively, and most of the DETs were down-regulated in kohlrabi. Gene ontology (GO) and KEGG pathway enrichment analyses showed that the DETs between genotypes are involved in cell wall loosening and expansion, cell cycle and division, carbohydrate metabolism, hormone transport, hormone signal transduction and in several transcription factors. The DETs identified in those categories may directly/indirectly relate to the initiation and development of tuberous stem in kohlrabi. In addition, the expression pattern of the hormone synthesis related DETs coincided with the endogenous IAA, IAAsp, GA, ABA, and tZ profiles in kohlrabi and broccoli seedlings, that were revealed in our phytohormone analysis. This is the first report on comparative transcriptome analysis for tuberous stem formation in kohlrabi at early growth periods. The resulting data could provide significant insights into the molecular mechanism underlying tuberous stem development in kohlrabi as well as in other tuberous organ forming crops.

Objective Brain-dead donor lung transplantation frequently requires reduction in the size of oversized lung grafts for patients with a small chest cavity. We focused on the role of three-dimensional computed tomography (3D-CT) volumetry for recipients on downsizing oversized lung grafts. Methods We performed 53 brain-dead donor bilateral lung transplantations, including 15 lobar lung transplants (Lobar group) and 38 standard lung transplants with full-sized grafts (Full group), between December 2010 and December 2018. Recipient chest volume before transplantation was measured using 3D-CT volumetry, and donor lung volume was evaluated by predicted total lung capacity. Post-transplant outcomes and pulmonary function were retrospectively compared between the groups. Results The ratio of the recipient chest volume to the donor lung volume was significantly lower in the Lobar group (0.42 ± 0.15) than in the Full group (0.77 ± 0.30, P

Brassica rapa L. is an important vegetable and oilseed crop. We investigated the distribution of the histone mark tri-methylation of H3K27 (H3K27me3) in B. rapa and its role in the control of gene expression at two stages of development (2-day cotyledons and 14-day leaves) and among paralogs in the triplicated genome. H3K27me3 has a similar distribution in two inbred lines, while there was variation of H3K27me3 sites between tissues. Sites that are specific to 2-day cotyledons have increased transcriptional activity, and low levels of H3K27me3 in the gene body region. In 14-day leaves, levels of H3K27me3 were associated with decreased gene expression. In the triplicated genome, H3K27me3 is associated with paralogs that have tissue-specific expression. Even though B. rapa and Arabidopsis thaliana are not closely related within the Brassicaceae, there is conservation of H3K27me3-marked sites in the two species. Both B. rapa and A. thaliana require vernalization for floral initiation with FLC being the major controlling locus. In all four BrFLC paralogs, low-temperature treatment increases H3K27me3 at the proximal nucleation site reducing BrFLC expression. Following return to normal temperature growth conditions, H3K27me3 spreads along all four BrFLC paralogs providing stable repression of the gene.

There is a wide variation of flowering time among lines of Brassica rapa L. Most B. rapa leafy (Chinese cabbage etc.) or root (turnip) vegetables require prolonged cold exposure for flowering, known as vernalization. Premature bolting caused by low temperature leads to a reduction in the yield/quality of these B. rapa vegetables. Therefore, high bolting resistance is an important breeding trait, and understanding the molecular mechanism of vernalization is necessary to achieve this goal. In this study, we demonstrated that BrFRIb functions as an activator of BrFLC in B. rapa. We showed a positive correlation between the steady state expression levels of the sum of the BrFLC paralogs and the days to flowering after four weeks of cold treatment, suggesting that this is an indicator of the vernalization requirement. We indicate that BrFLCs are repressed by the accumulation of H3K27me3 and that the spreading of H3K27me3 promotes stable FLC repression. However, there was no clear relationship between the level of H3K27me3 in the BrFLC and the vernalization requirement. We also showed that if there was a high vernalization requirement, the rate of repression of BrFLC1 expression following prolonged cold treatments was lower.

The efficiency with which polymeric semiconductors can be chemically doped—and the charge carrier densities that can thereby be achieved—is determined primarily by the electrochemical redox potential between the π-conjugated polymer and the dopant species1,2. Thus, matching the electron affinity of one with the ionization potential of the other can allow effective doping3,4. Here we describe a different process—which we term ‘anion exchange’—that might offer improved doping levels. This process is mediated by an ionic liquid solvent and can be pictured as the effective instantaneous exchange of a conventional small p-type dopant anion with a second anion provided by an ionic liquid. The introduction of optimized ionic salt (the ionic liquid solvent) into a conventional binary donor–acceptor system can overcome the redox potential limitations described by Marcus theory5, and allows an anion-exchange efficiency of nearly 100 per cent. As a result, doping levels of up to almost one charge per monomer unit can be achieved. This demonstration of increased doping levels, increased stability and excellent transport properties shows that anion-exchange doping, which can use an almost infinite selection of ionic salts, could be a powerful tool for the realization of advanced molecular electronics. The limitations of conventional chemical doping of polymeric semiconductors can be overcome by adding a second ionic species into the system, leading to enhanced doping, electrical conductivity and stability.

The fusarium yellows resistance (YR) gene FocBo1 was previously identified and the DNA markers were developed to assist the breeding of YR cultivars in Brassica oleracea. However, the further analysis revealed discrepancies between the phenotypes and the genotypes predicted by those DNA markers in cabbage commercial cultivars. Since this discrepancy seemed to be due to unknown susceptible alleles of focbo1, we sequenced the gene in 19 accessions to determine the sequence variations between alleles and found that there were two resistant FocBo1 alleles and six susceptible alleles in the investigated population. The newly designed PCR markers detected three mutations in the susceptible alleles that generate premature termination codons. These were shown to accurately distinguish resistant and susceptible alleles in more than 200 accessions of B. oleracea inbred lines and cultivars. The study revealed that the locus is represented by 37.2% resistant and 62.8% susceptible alleles within seventy-eight commercial cultivars. Structural analysis of the gene revealed that a part of the allelic variation comes from intragenic recombination between alleles. Our results enable a more precise prediction of the phenotype by marker assisted selection, promoting the production of YR cultivars in B. oleracea.

Long noncoding RNAs (lncRNAs) are RNA fragments that generally do not code for a protein but are involved in epigenetic gene regulation. In this study, lncRNAs of Brassica rapa were classified into long intergenic noncoding RNAs, natural antisense RNAs, and intronic noncoding RNAs and their expression analyzed in relation to genome-wide 24-nt small interfering RNAs (siRNAs), DNA methylation, and histone H3 lysine 27 trimethylation marks (H3K27me3). More than 65% of the lncRNAs analyzed consisted of one exon, and more than 55% overlapped with inverted repeat regions (IRRs). Overlap of lncRNAs with IRRs or genomic regions encoding for 24-nt siRNAs resulted in increased DNA methylation levels when both were present. LncRNA did not overlap greatly with H3K27me3 marks, but the expression level of intronic noncoding RNAs that did coincide with H3K27me3 marks was higher than without H3K27me3 marks. The Brassica genus comprises important vegetables and oil seed crops grown across the world. B. rapa is a diploid (AA genome) thought to be one of the ancestral species of both B. juncea (AABB genome) and B. napus (AACC) through genome merging (allotetrapolyploidization). Complex genome restructuring and epigenetic alterations are thought to be involved in these allotetrapolyploidization events. Comparison of lncRNAs between B. rapa and B. nigra, B. oleracea, B. juncea, and B. napus showed the highest conservation with B. oleracea. This study presents a comprehensive analysis of the epigenome structure of B. rapa at multi-epigenetic levels (siRNAs, DNA methylation, H3K27me3, and lncRNAs) and identified a suite of candidate lncRNAs that may be epigenetically regulated in the Brassica genus.

The Brassica genus comprises of agro-economically important vegetables. Disease causes great yield loss of Brassica vegetables worldwide. Different traditional methods such as crop rotation and chemical control have limited effect on different diseases of Brassica vegetables and cannot completely eradicate the pathogens by these methods. Development of disease resistant cultivars is one of the most effective, ecofriendly, and cheapest measure to control Brassica diseases. With the development of genomics, molecular biology techniques, and biological methods, it is possible to discover and introduce resistance (R) genes to efficiently control the plant diseases caused by pathogens. Some R genes of major diseases such as Fusarium wilt and clubroot in Brassica vegetables have been already identified. Therefore, we will focus to review the Fusarium wilt and clubroot resistance in Brassica vegetables and the methodologies for identification, mapping, and pyramiding of R genes/quantitative trait loci (QTLs) to develop disease resistant cultivars. These techniques will be helpful for sustainable crop production and to maintain global food security and contribute to ensure protection of food supply in the Asian country as well as throughout the world.

Chinese cabbage (Brassica rapa L. var. pekinensis) is an economically important vegetable providing nutrients such as fiber, calcium and vitamins. Most cultivars of Chinese cabbage are F1 hybrids with vegetative heterosis, and harvesting of commercial F1 hybrid seeds makes use of self-incompatibility or cytoplasmic male sterility. Production of Chinese cabbage is always threatened by abiotic and biotic stress; climate change and increasing numbers of races and varieties of pathogens are also serious problems. The demand for abiotic or biotic resistant cultivars is growing year by year. An effective breeding method is desired, and marker-assisted selection (MAS) is a leading candidate. To apply MAS, identification of the causative gene or the locus linked to the causative gene controlling a trait for breeding is required. We review the recent research using molecular biology approaches and discuss how this information can apply to Chinese cabbage breeding.

KEY MESSAGE: Fusarium yellows resistant and susceptible lines in Brassica rapa showed different salicylic acid responses; the resistant line showed a similar response to previous reports, but the susceptible line differed. Fusarium yellows caused by Fusarium oxysporum f. sp. conglutinans (Foc) is an important disease. Previous studies showed that genes related to salicylic acid (SA) response were more highly induced following Foc infection in Brassica rapa Fusarium yellows resistant lines than susceptible lines. However, SA-induced genes have not been identified at the whole genome level and it was unclear whether they were up-regulated by Foc inoculation. Transcriptome analysis with and without SA treatment in the B. rapa Fusarium yellows susceptible line 'Misugi' and the resistant line 'Nanane' was performed to obtain insights into the relationship between SA sensitivity/response and Fusarium yellows resistance. 'Nanane's up-regulated genes were related to SA response and down-regulated genes were related to jasmonic acid (JA) or ethylene (ET) response, but differentially expressed genes in 'Misugi' were not. This result suggests that Fusarium yellows resistant and susceptible lines have a different SA response and that an antagonistic transcription between SA and JA/ET responses was found only in a Fusarium yellows resistant line. SA-responsive genes were induced by Foc inoculation in Fusarium yellows resistant (RJKB-T23) and susceptible lines (RJKB-T24). By contrast, 39 SA-induced genes specific to RJKB-T23 might function in the defense response to Foc. In this study, SA-induced genes were identified at the whole genome level, and the possibility, the defense response to Foc observed in a resistant line could be mediated by SA-induced genes, is suggested. These results will be useful for future research concerning the SA importance in Foc or other diseases resistance in B. rapa.

The genus Brassica contains important vegetable crops, which serve as a source of oil seed, condiments, and forages. However, their production is hampered by various diseases such as clubroot and Fusarium wilt, especially in Brassica vegetables. Soil-borne diseases are difficult to manage by traditional methods. Host resistance is an important tool for minimizing disease and many types of resistance (R) genes have been identified. More than 20 major clubroot (CR) disease-related loci have been identified in Brassica vegetables and several CR-resistant genes have been isolated by map-based cloning. Fusarium wilt resistant genes in Brassica vegetables have also been isolated. These isolated R genes encode the toll-interleukin-1 receptor/nucleotide-binding site/leucine-rice-repeat (TIR-NBS-LRR) protein. DNA markers that are linked with disease resistance allele have been successfully applied to improve disease resistance through marker-assisted selection (MAS). In this review, we focused on the recent status of identifying clubroot and Fusarium wilt R genes and the feasibility of using MAS for developing disease resistance cultivars in Brassica vegetables.

Heterosis or hybrid vigour is a phenomenon in which hybrid progeny exhibit superior yield and biomass to parental lines and has been used to breed F1 hybrid cultivars in many crops. A similar level of heterosis in all F1 individuals is expected as they are genetically identical. However, we found variation in rosette size in individual F1 plants from a cross between C24 and Columbia-0 accessions of Arabidopsis thaliana. Big-sized F1 plants had 26.1% larger leaf area in the first and second leaves than medium-sized F1 plants at 14 days after sowing in spite of the identical genetic background. We identified differentially expressed genes between big- and medium-sized F1 plants by microarray, genes involved in the category of stress response were overrepresented. We made transgenic plants overexpressing 21 genes, which were differentially expressed between the two size classes, and some lines had increased plant size at 14 or 21 days after sowing but not at all time points during development. Change of expression levels in stress-responsive genes among individual F1 plants could generate the variation in plant size of individual F1 plants in A. thaliana.

Heterosis or hybrid vigour is a phenomenon in which hybrid progeny exhibit superior yield and biomass to parental lines and has been used to breed F1 hybrid cultivars in many crops. A similar level of heterosis in all F1 individuals is expected as they are genetically identical. However, we found variation in rosette size in individual F1 plants from a cross between C24 and Columbia-0 accessions of Arabidopsis thaliana. Big-sized F1 plants had 26.1% larger leaf area in the first and second leaves than medium-sized F1 plants at 14 days after sowing in spite of the identical genetic background. We identified differentially expressed genes between big- and medium-sized F1 plants by microarray; genes involved in the category of stress response were overrepresented. We made transgenic plants overexpressing 21 genes, which were differentially expressed between the two size classes, and some lines had increased plant size at 14 or 21 days after sowing but not at all time points during development. Change of expression levels in stress-responsive genes among individual F1 plants could generate the variation in plant size of individual F1 plants in A. thaliana.

The genus Brassica includes many economically important crops providing nutrition as well as health-promoting substances. Most cultivars of the Brassica vegetables are F1 hybrids, and breeding system was successfully established by effectively applying the phenomenon of heterosis or self-incompatibility. However, their production is constantly threatened by abiotic and biotic stresses such as the increasing numbers of races and isolates of pathogens, inappropriate cropping systems, and changing climate. Traditional methods of control are often costly and environmentally damaging, while the ideal way is to mine and use the abiotic or biotic resistance from the crop hosts. Fortunately, genomics and molecular genetics enables the rapid discover and application of plant breeding to improve adaptation to environmental conditions and abiotic or biotic resistance. Herein, we have summarized the important characteristics for breeding of the Brassica vegetables, including the trials for understanding the molecular mechanisms with genetic and epigenetic approaches. Some future perspectives are also given concerning how to efficiently use these genes and overcome global climate change.

Flowering time is an important agronomic trait for Brassica rapa crops, and previous breeding work in Brassica has successfully transmitted other important agronomic traits from donor species. However, there has been no previous attempts to produce hybrids replacing the original Brassica FLC alleles with alien FLC alleles. In this paper, we introduce the creation of a chromosome substitution line (CSSL) containing a homozygous introgression of Flowering Locus C from Brassica oleracea (BoFLC2) into a B. rapa genomic background, and characterize the CSSL line with respect to the parental cultivars. The preferential transmission of alien chromosome inheritance and the pattern of transmission observed during the production of the CSSLs are also discussed.

DNA methylation is an epigenetic gene regulatory mechanism that plays an essential role in gene expression, transposon silencing, genome imprinting and plant development. We investigated the influence of DNA methylation on gene expression in Brassica rapa L., to understand whether epigenetic differences exist between inbred lines. Genome-wide DNA methylation was analysed by methylated DNA immunoprecipitation sequencing (MeDIP-seq) of 14-day-old first and second leaves from two inbred lines of Chinese cabbage, one susceptible and one resistant to fusarium yellows caused by Fusarium oxysporum f. sp. conglutinans. MACS (model-based analysis for ChIP-seq) identified DNA methylation peaks in genic regions including 2 kb upstream, exon, intron and 2 kb downstream. More than 65% of genes showed similar patterns of DNA methylation in the genic regions in the two inbred lines. DNA methylation states of the two inbred lines were compared with their transcriptome. Genes having DNA methylation in the intron and in the 200 bp upstream and downstream regions were associated with a lower expression level in both lines. A small number of genes showed a negative correlation between differences in DNA methylation levels and differences in transcriptional levels in the two inbred lines, suggesting that DNA methylation in these genes results in transcriptional suppression.

Heterosis or hybrid vigor is a phenomenon where hybrid progeny have superior performance compared to their parental inbred lines. This is important in the use of F1 hybrid cultivars in many crops and vegetables. However, the molecular mechanism of heterosis is not clearly understood. Gene interactions between the two genomes such as dominance, overdominance, and epistasis have been suggested to explain the increased biomass and yield. Genetic analyses of F1 hybrids in maize, rice, and canola have defined a large number of quantitative trait loci, which may contribute to heterosis. Recent molecular analyses of transcriptomes together with reference to the epigenome of the parents and hybrids have begun to uncover new facts about the generation of heterosis. These include the identification of gene expression changes in hybrids, which may be important for heterosis, the role of epigenetic processes in heterosis, and the development of stable high yielding lines.

Flowering time is an important agronomic trait for Brassica rapa crops, and previous breeding work in Brassica has successfully transmitted other important agronomic traits from donor species. However, there has been no previous attempts to produce hybrids replacing the original Brassica FLC alleles with alien FLC alleles. In this paper, we introduce the creation of a chromosome substitution line (CSSL) containing a homozygous introgression of Flowering Locus C from Brassica oleracea (BoFLC2) into a B. rapa genomic background, and characterize the CSSL line with respect to the parental cultivars. The preferential transmission of alien chromosome inheritance and the pattern of transmission observed during the production of the CSSLs are also discussed.