Complete Genome Sequences of Four Mycobacteriophages Involved in Directed Evolution against Undisputed Mycobacterium abscessus Clinical Strains.

Phage therapy is still in its infancy, but it is increasingly promising as a future alternative for treating antibiotic-resistant bacteria. To investigate the effect of phages on Mycobacterium abscessus complex (MABC), we isolated 113 environmental phages, grown them to high titres, and assayed them on MABC clinical strains through the spot test. Of all the phages, only 16 showed killing activity. Their activity was so temperate to MABC that they could not generate any plaque-forming units (PFUs). The Appelmans method of directed evolution was carried out to evolve these 16 phages into more lytic ones. After only 11 of 30 rounds of evolution, every single clinical strain in our collection, including those that were unsusceptible up to this point, could be lysed by at least one phage. The evolved phages were able to form PFUs on the clinical strains tested. Still, they are temperate at best and require further training. The genomes of one random parental phage and three random evolved phages from Round 13 were sequenced, revealing a diversity of clusters and genes of a variety of evolutionary origins, mostly of unknown function. These complete annotated genomes will be key for future molecular characterisations.

Karyotyping of aneuploid and polyploid plants from low coverage whole-genome resequencing.

BACKGROUND: Karyotype, as a basic characteristic of species, provides valuable information for fundamental theoretical research and germplasm resource innovation. However, traditional karyotyping techniques, including fluorescence in situ hybridization (FISH), are challenging and low in efficiency, especially when karyotyping aneuploid and polyploid plants. The use of low coverage whole-genome resequencing (lcWGR) data for karyotyping was explored, but existing methods are complicated and require control samples. RESULTS: In this study, a new protocol for molecular karyotype analysis was provided, which proved to be a simpler, faster, and more accurate method, requiring no control. Notably, our method not only provided the copy number of each chromosome of an individual but also an accurate evaluation of the genomic contribution from its parents. Moreover, we verified the method through FISH and published resequencing data. CONCLUSIONS: This method is of great significance for species evolution analysis, chromosome engineering, crop improvement, and breeding.

Analysis of Phenotypic and Genotypic Susceptibility to Clarithromycin and Amikacin of Mycobacterium abscessus Complex Strains Isolated from Cystic Fibrosis Patients.

Mycobacterium abscessus complex infections are ever on the rise. To curb their increasing evolution, we performed an in-depth study of 43 clinical isolates of cystic fibrosis patients obtained from 2009 to 2020. We identified their subspecies, uncovered their genotypic resistance profiles, characterised their antibiotic-resistant genes, and assessed their phenotypic antibiotic susceptibilities. The phenotypic and genotypic methods showed total agreement in terms of resistance to clarithromycin and amikacin. Of the 43 clinical strains, 28 belonged to M. abscessus subsp. abscessus (65.1%), 13 to M. abscessus subsp. massiliense (30.2%), and 2 to M. abscessus subsp. bolletii (4.6%). The resistant rates for clarithromycin and amikacin, the two main drugs against M. abscessus complex pulmonary infections, were 64.2% and 14.2%, respectively. We found three strains of M. abscessus subsp. abscessus that showed heteroresistance in the rrl and rrs genes, and these strains also presented double-resistance since they were macrolide- and aminoglycoside-resistant. M. abscessus subsp. abscessus showed a high minimum inhibitory concentration (MIC) and a resistant percentage larger than or equal to 88% to cefoxitin, ciprofloxacin, moxifloxacin, doxycycline, imipenem, and trimethoprim-sulfamethoxazole. These results show a panorama of the high resistance of Mycobacterium abscessus complex to current drugs for cystic fibrosis patients. Thus, other treatment methods are urgently needed.

Exploring the Mechanism of White Peony in the Treatment of Lupus Nephritis Based on Network Pharmacology and Molecular Docking.

INTRODUCTION: Lupus nephritis (LN) is still a great burden for patients with systemic lupus erythematosus, and also one of the most severe complications of SLE. Radix Paeoniae Alba (white peony, WP) is proved with potential efficacy in treating LN. This study was to explore the effective ingredients, potential targets, and pathways of WP in treating LN based on network pharmacology and molecular docking. METHODS: The active ingredients and potential protein targets of WP were gathered on Traditional Chinese Medicine Systematic Pharmacology Database and predicted by Swiss Target Prediction. LN-related therapeutic targets were acquired from multiple databases including Genecards, DisGeNET, OMIM, Drugbank, and PharmGKB. The intersection targets of WP and LN were acquired through Veeny 2.1.0. Protein-Protein Interaction (PPI) network was established by STRING. The results were then visualized by Cytoscape version 3.7.1. to study the mechanisms of WP on LN, gene ontology and functional enrichment analysis were carried out. Finally, molecular docking presented with the binding ability of key targets and major active components. RESULTS: We acquired a total of 13 active ingredients and 260 potential targets of WP. Among them, the intersection with targets of LN were 82 proteins. These targets were regarded as potential therapeutic targets. Through PPI network, we found that the top three proteins were RAC-alpha serine/threonine protein kinase (AKT1), vascular endothelial growth factor A (VEGFA), and transcription factor Jun (JUN), and their corresponding components were kaempferol, paeoniflorin, lactiflorin, paeoniflorgenone, etc. The results of enrichment analysis suggested that WP treatment for LN mainly involves in signaling pathways in cancer, lipid and atherosclerosis, advanced glycation end product (AGE)-receptor of AGE (RAGE) pathways, C-type lectin receptor and nuclear factor (NF)-kappa B signaling pathways. Molecular docking predicted that the above components have excellent affinity to AKT1, VEGFA, and JUN. CONCLUSIONS: This study gave an insight into the key target proteins and potential underlying pharmacological mechanism of WP in treating LN, which provided evidence for further researches on the mechanism of WP on LN.

Genome balance and dosage effect drive allopolyploid formation in Brassica.

Polyploidy is a major evolutionary force that has shaped plant diversity. However, the various pathways toward polyploid formation and interploidy gene flow remain poorly understood. Here, we demonstrated that the immediate progeny of allotriploid AAC Brassica (obtained by crossing allotetraploid Brassica napus and diploid Brassica rapa) was predominantly aneuploids with ploidal levels ranging from near-triploidy to near-hexaploidy, and their chromosome numbers deviated from the theoretical distribution toward increasing chromosome numbers, suggesting that they underwent selection. Karyotype and phenotype analyses showed that aneuploid individuals containing fewer imbalanced chromosomes had higher viability and fertility. Within three generations of self-fertilization, allotriploids mainly developed into near or complete allotetraploids similar to B. napus via gradually increasing chromosome numbers and fertility, suggesting that allotriploids could act as a bridge in polyploid formation, with aneuploids as intermediates. Self-fertilized interploidy hybrids ultimately generated new allopolyploids carrying different chromosome combinations, which may create a reproductive barrier preventing allotetraploidy back to diploidy and promote gene flow from diploids to allotetraploids. These results suggest that the maintenance of a proper genome balance and dosage drove the recurrent conversion of allotriploids to allotetraploids, which may contribute to the formation and evolution of polyploids.

Exploring the Mechanism of White Peony in the Treatment of Lupus Nephritis Based on Network Pharmacology and Molecular Docking

Introduction: Lupus nephritis (LN) is still a great burden for patients with systemic lupus erythematosus, and also one of the most severe complications of SLE. Radix Paeoniae Alba (white peony, WP) is proved with potential efficacy in treating LN. This study was to explore the effective ingredients, potential targets, and pathways of WP in treating LN based on network pharmacology and molecular docking. Methods: The active ingredients and potential protein targets of WP were gathered on Traditional Chinese Medicine Systematic Pharmacology Database and predicted by Swiss Target Prediction. LN-related therapeutic targets were acquired from multiple databases including Genecards, DisGeNET, OMIM, Drugbank, and PharmGKB. The intersection targets of WP and LN were acquired through Veeny 2.1.0. Protein-Protein Interaction (PPI) network was established by STRING. The results were then visualized by Cytoscape version 3.7.1. to study the mechanisms of WP on LN, gene ontology and functional enrichment analysis were carried out. Finally, molecular docking presented with the binding ability of key targets and major active components. Results: We acquired a total of 13 active ingredients and 260 potential targets of WP. Among them, the intersection with targets of LN were 82 proteins. These targets were regarded as potential therapeutic targets. Through PPI network, we found that the top three proteins were RAC-alpha serine/threonine protein kinase (AKT1), vascular endothelial growth factor A (VEGFA), and transcription factor Jun (JUN), and their corresponding components were kaempferol, paeoniflorin, lactiflorin, paeoniflorgenone, etc (AU)

The expression of respiratory tract virus in pediatric glomerular disease: a retrospective study of 45 renal biopsy in China.

BACKGROUND: More attention has been put on the relationship between pediatric glomerular disease and respiratory tract virus infection. Children with glomerular illness, however, are uncommonly found to have biopsy-proven pathological evidence of viral infection. The purpose of this study is to determine whether and what kind of respiratory viruses are found in renal biopsy from glomerular disorders. METHODS: We used a multiplex PCR to identify a wide range of respiratory tract viruses in the renal biopsy samples (n = 45) from children with glomerular disorders and a specific PCR to verify their expression. RESULTS: These case series included 45 of 47 renal biopsy specimens, with 37.8% of male and 62.2% of female patients. Indications for a kidney biopsy were present in all of the individuals. In 80% of the samples, respiratory syncytial virus was discovered. Following that, the RSV subtypes in several pediatric renal disorders were found. There were 16 RSVA positives, 5 RSVB positives, and 15 RSVA/B positives, accounting for 44.4%, 13.9%, and 41.7%, respectively. Nephrotic syndrome samples made up 62.5% of RSVA positive specimens. The RSVA/B-positive was detected in all pathological histological types. CONCLUSIONS: Patients with glomerular disease exhibit respiratory tract viral expression in the renal tissues, especially respiratory syncytial virus. This research offers new information on the detection of respiratory tract viruses in renal tissue, which may facilitate the identification and treatment of pediatric glomerular diseases.

Real-world treatment patterns of metastatic non-small cell lung cancer patients receiving epidermal growth factor receptor tyrosine kinase inhibitors.

BACKGROUND: Several epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKI) have been approved for first-line (1L) treatment of EGFR-mutated metastatic non-small cell lung cancer (mNSCLC) in the United States (US). Real-world analyses of 1L treatment patterns with EGFR TKIs, including the third-generation EGFR TKI osimertinib which was most recently approved in 2018, are still sparse. METHODS: This retrospective observational study used data from IQVIA's prescription claims (LRx) and medical claims (Dx) databases. mNSCLC patients newly treated with any EGFR TKI in the 1L setting were identified from January 1, 2015 to April 30, 2020; the first date of EGFR TKI (third-generation osimertinib, first-generation [erlotinib, gefitinib], or second-generation [afatinib, dacomitinib]) was the index date. Treatment patterns were reported in the cohorts stratified by 1L EGFR TKI. RESULTS: A total of 2505 patients were included in the study (982 osimertinib, 1060 first-generation, and 463 second-generation EGFR TKI). Beginning in 2018, osimertinib became the most common 1L EGFR TKI (66.7%) and in early 2020, it accounted for 90.6% of 1L EGFR TKIs. Nearly all patients (>97%) were treated with 1L EGFR TKI monotherapy. Patients with 1L osimertinib had longer treatment duration compared to patients with 1L first- or second-generation EGFR TKI (median months: 17.8 vs. 8.7 vs. 10.5, respectively; log-rank test for comparisons with osimertinib p < 0.0001) over median follow-up times of 9.8, 20.5, and 19.3 months. 32.5% and 36.3% of the first- and second-generation EGFR TKI cohorts, respectively, had evidence of 2L treatment. Osimertinib monotherapy accounted for the majority of 2L treatments (58.3%/60.7%) and 11.3%/8.9% had 2L chemotherapy or immuno-oncology therapy following 1L first- or second-generation EGFR TKI. CONCLUSION: In this real-world study of a US claims database, 1L treatment duration was longer with osimertinib compared with other EGFR TKIs. Future studies with longer follow-up are recommended to understand treatment patterns after progression on EGFR TKIs.

Transcription Factor SmSPL2 Inhibits the Accumulation of Salvianolic Acid B and Influences Root Architecture.

The SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE (SPL) transcription factor play vital roles in plant growth and development. Although 15 SPL family genes have been recognized in the model medical plant Salvia miltiorrhiza Bunge, most of them have not been functionally characterized to date. Here, we performed a careful characterization of SmSPL2, which was expressed in almost all tissues of S. miltiorrhiza and had the highest transcriptional level in the calyx. Meanwhile, SmSPL2 has strong transcriptional activation activity and resides in the nucleus. We obtained overexpression lines of SmSPL2 and rSmSPL2 (miR156-resistant SmSPL2). Morphological changes in roots, including longer length, fewer adventitious roots, decreased lateral root density, and increased fresh weight, were observed in all of these transgenic lines. Two rSmSPL2-overexpressed lines were subjected to transcriptome analysis. Overexpression of rSmSPL2 changed root architectures by inhibiting biosynthesis and signal transduction of auxin, while triggering that of cytokinin. The salvianolic acid B (SalB) concentration was significantly decreased in rSmSPL2-overexpressed lines. Further analysis revealed that SmSPL2 binds directly to the promoters of Sm4CL9, SmTAT1, and SmPAL1 and inhibits their expression. In conclusion, SmSPL2 is a potential gene that efficiently manipulate both root architecture and SalB concentration in S. miltiorrhiza.

Development and validation of nomogram prediction model for severe kidney disease in children with Henoch-Schönlein purpura: A prospective analysis of two independent cohorts-forecast severe kidney disease outcome in 2,480 hospitalized Henoch-Schönlein purpura children.

This study aimed to develop and validate a nomogram to forecast severe kidney disease (SKD) outcomes for hospitalized Henoch-Schönlein purpura (HSP) children. The predictive model was built based on a primary cohort that included 2,019 patients with HSP who were diagnosed between January 2009 and December 2013. Another cohort consisting of 461 patients between January 2014 and December 2016 was recruited for independent validation. Patients were followed up for 24 months in development/training and validation cohorts. The data were gathered at multiple time points after HSP (at 3, 6, 12, and 24 months) covering severe kidney disease as the severe outcome after HSP. The least absolute shrinkage and selection operator (LASSO) regression model was utilized to decrease data dimension and choose potentially relevant features, which included socioeconomic factors, clinical features, and treatments. Multivariate Cox proportional hazards analysis was employed to establish a novel nomogram. The performance of the nomogram was assessed on the aspects of its calibration, discrimination, and clinical usefulness. The nomogram comprised serious skin rash or digestive tract purpura, severe gastrointestinal (GI) manifestations, recurrent symptoms, and renal involvement as predictors of SKD, providing favorable calibration and discrimination in the training dataset with a C-index of 0.751 (95% CI, 0.734-0.769). Furthermore, it demonstrated receivable discrimination in the validation cohort, with a C-index of 0.714 (95% CI, 0.678-0.750). With the use of decision curve analysis, the nomogram was proven to be clinically useful. The nomogram independently predicted SKD in HSP and displayed favorable discrimination and calibration values. It could be convenient to promote the individualized prediction of SKD in patients with HSP.

Identifying key genes and functionally enriched pathways in Th2-high asthma by weighted gene co-expression network analysis.

BACKGROUND: Asthma is a chronic lung disease characterized by reversible inflammation of the airways. The imbalance of Th1/Th2 cells plays a significant role in the mechanisms of asthma. The aim of this study was to identify asthma-related key genes and functionally enriched pathways in a Th2-high group by using weighted gene coexpression network analysis (WGCNA). METHODS: The gene expression profiles of GSE4302, which included 42 asthma patients and 28 controls, were selected from the Gene Expression Omnibus (GEO). A gene network was constructed, and genes were classified into different modules using WGCNA. Gene ontology (GO) was performed to further explore the potential function of the genes in the most related module. In addition, the expression profile and diagnostic capacity (ROC curve) of hub genes of interest were verified by dataset GSE67472. RESULTS: In dataset GSE4302, subjects with asthma were divided into Th2-high and Th2-low groups according to the expression of the SERPINB2, POSTN and CLCA1 genes. A weighted gene coexpression network was constructed, and genes were classified into 7 modules. Among them, the red module was most closely associated with Th2-high asthma, which contained 60 genes. These genes were significantly enriched in different biological processes and molecular functions. A total of 8 hub genes (TPSB2, CPA3, ITLN1, CST1, SERPINB10, CEACAM5, CHD26 and P2RY14) were identified, and the expression levels of these genes (except TPSB2) were confirmed in dataset GSE67472. ROC curve analysis validated that the expression of these 8 genes exhibited excellent diagnostic efficiency for Th2-high asthma and Th2-low asthma. CONCLUSIONS: The study provides a novel perspective on Th2-high asthma by WGCNA, and the hub genes and potential pathways involved may be beneficial for the diagnosis and management of Th2-high asthma.

LncRNA-miRNA-mRNA Network Analysis Reveals the Potential Biomarkers in Crohn's Disease Rats Treated with Herb-Partitioned Moxibustion.

Background: Long noncoding RNA (lncRNA) is receiving growing attention in Crohn's disease (CD). However, the mechanism by which herb-partitioned moxibustion (HPM) regulates the expression and functions of lncRNAs in CD rats is still unclear. The aim of our study is to identify lncRNA-miRNA-mRNA network potential biological functions in CD. Methods: RNA sequencing and microRNA (miRNA) sequencing were carried out to analyze lncRNA, miRNA and mRNA expression profiles among the CD rats, normal control rats, and CD rats after HPM treatment and constructed the potential related lncRNA-miRNA-mRNA competing endogenous RNA (ceRNA) networks. Then, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, protein-protein interaction (PPI) analysis and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to explore potentially important genes in ceRNA networks. Results: A total of 189 lncRNAs, 32 miRNAs and 463 mRNAs were determined as differentially expressed (DE) genes in CD rats compared to normal control rats, and 161 lncRNAs, 12 miRNAs and 130 mRNAs were identified as remarkably DE genes in CD rats after HPM treatment compared to CD rats. GO analysis indicated that the target genes were most enriched in cAMP and in KEGG pathway analysis the main pathways included adipocytokine, PPAR, AMPK, FoxO and PI3K-Akt signaling pathway. Finally, qRT-PCR results confirmed that lncRNA LOC102550026 sponged miRNA-34c-5p to regulate the intestinal immune inflammatory response by targeting Pck1. Conclusion: By constructing a ceRNA network with lncRNA-miRNA-mRNA, PCR verification, and KEGG analysis, we revealed that LOC102550026/miRNA-34c-5p/Pck1 axis and adipocytokine, PPAR, AMPK, FoxO, and PI3K-Akt signaling pathways might regulate the intestinal immune-inflammatory response, and HPM may regulate the lncRNA LOC102550026/miR-34c-5p/Pck1 axis and adipocytokine, PPAR, AMPK, FoxO, and PI3K-Akt signaling pathways, thus improving intestinal inflammation in CD. These findings may be novel potential targets in CD.

Stimulating Customer Inspiration Through Online Brand Community Climates: The Mediating Role of Customer Interaction.

This study examines the impacts of the online brand community (OBC) climate on customer interaction and customer inspiration, which are yet under-explored in the extant literature. The data were collected online from the Chinese respondents (N = 504) to analyze the proposed constructs of the study. Findings show that supportive OBC climate and controlled OBC climate are positively related to customer interaction (including information interaction and social interaction) and exert a significant and positive impact on customer inspiration. A mediating impact of customer interaction is found on the relationship between OBC climate and customer inspiration. This study unravels the importance and mechanism of customer-brand relationships in the online environment and illuminates pathways for marketers and policymakers to positively influence customer inspiration for business promotion. This study updates existing literature boxes of consumer behavior and marketing in the context of online customer-brand relationships. Limitations and future research directions are noted.

SmSPL6 Induces Phenolic Acid Biosynthesis and Affects Root Development in Salvia miltiorrhiza.

Salvia miltiorrhiza is a renowned model medicinal plant species for which 15 SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) family genes have been identified; however, the specific functions of SmSPLs have not been well characterized as of yet. For this study, the expression patterns of SmSPL6 were determined through its responses to treatments of exogenous hormones, including indole acetic acid (IAA), gibberellic acid (GA3), methyl jasmonic acid (MeJA), and abscisic acid (ABA). To characterize its functionality, we obtained SmSPL6-ovexpressed transgenic S. miltiorrhiza plants and found that overexpressed SmSPL6 promoted the accumulation of phenolic acids and repressed the biosynthesis of anthocyanin. Meanwhile, the root lengths of the SmSPL6-overexpressed lines were significantly longer than the control; however, both the fresh weights and lateral root numbers decreased. Further investigations indicated that SmSPL6 regulated the biosynthesis of phenolic acid by directly binding to the promoter regions of the enzyme genes Sm4CL9 and SmCYP98A14 and activated their expression. We concluded that SmSPL6 regulates not only the biosynthesis of phenolic acids, but also the development of roots in S. miltiorrhiza.

Transcription factor SmSPL7 promotes anthocyanin accumulation and negatively regulates phenolic acid biosynthesis in Salvia miltiorrhiza.

Plant-specific SQUAMOSA promoter-binding protein-like (SPL) transcription factors play critical regulatory roles during plant growth and development. However, the functions of SPLs in Salvia miltiorrhiza (SmSPLs; a model medicinal plant) have not been reported. Here, the expression patterns and functions of SmSPL7 were characterized in S. miltiorrhiza. SmSPL7 was expressed in all parts of S. miltiorrhiza, with the highest expression level in the leaves, and could be inhibited by multiple hormones, including methyl jasmonate, auxin, abscisic acid, and gibberellin. SmSPL7 is localized within the nucleus and exhibits robust transcriptional activation activity. Transgenic lines overexpressing SmSPL7 demonstrated pronounced growth inhibition, accompanied by increased anthocyanin accumulation via the genetic activation of the anthocyanin biosynthesis pathway. However, SmSPL7 overexpression significantly decreased salvianolic acid B (SalB) production by inhibiting the transcripts of genes implicated in its biosynthesis pathway. Further analysis indicated that SmSPL7 directly binds to SmTAT1 and Sm4CL9 promoters and blocks their expression to inhibit the biosynthesis of SalB. Taken together, these results indicate that SmSPL7 is a negative regulator of SalB biosynthesis but positively regulates anthocyanin accumulation in S. miltiorrhiza. These findings provide new insights into the functionality of the SPL family while establishing an important foundation for further uncovering the crucial roles of SmSPL7 in the growth of S. miltiorrhiza.

Real-World Assessment of Asthma Specialist Visits Among U.S. Patients with Severe Asthma.

BACKGROUND: U.S. guidelines recommend that patients with severe asthma be referred to specialists (allergists/immunologists or pulmonologists) for systematic assessment or comanagement; however, contemporary, real-world data on the frequency and impact of specialist care among U.S. severe asthma patients are lacking. OBJECTIVES: To quantify the frequency of asthma specialist visits among U.S. patients with severe asthma, identify patient demographic and clinical characteristics associated with specialist visits and describe health outcomes following specialist care. METHODS: Severe asthma patients aged 6 years or older were identified between January 1, 2015, and December 31, 2017, in the IQVIA PharMetrics® Plus database of commercially insured individuals, based on Healthcare Effectiveness Data and Information Set (HEDIS) criteria and Global Initiative for Asthma (GINA) step 4 or 5 treatment regimens. The frequency of asthma specialist (allergist/immunologist or pulmonologist) visits was described over 2 years. Patient characteristics associated with having 1 or more specialist visits were analyzed using multivariate regressions. Asthma exacerbations and health care resource utilization before and after specialist visit were compared. RESULTS: Of 54,332 patients identified, 38.2% had 1 or more specialist visits over 2 years. Patient characteristics predictive of specialist visits were asthma exacerbation frequency, younger age, and allergy/respiratory comorbidity burden (all P < .001). Among patients with 1 or more specialist visits, a lower prevalence of asthma exacerbations and rescue inhaler use was observed following the first observed specialist visit. CONCLUSIONS: Specialist care was observed in fewer than half of U.S. patients with severe asthma and was least frequent among older adult patients and those with more nonrespiratory comorbidities. Increased specialist involvement in managing severe asthma may help improve care and patient outcomes.

Chromosome inheritance and meiotic stability in allopolyploid Brassica napus.

Homoeologous recombination, aneuploidy, and other genetic changes are common in resynthesized allopolyploid Brassica napus. In contrast, the chromosomes of cultivars have long been considered to be meiotically stable. To gain a better understanding of the underlying mechanisms leading to stabilization in the allopolyploid, the behavior of chromosomes during meiosis can be compared by unambiguous chromosome identification between resynthesized and natural B. napus. Compared with natural B. napus, resynthesized lines show high rates of nonhomologous centromere association, homoeologous recombination leading to translocation, homoeologous chromosome replacement, and association and breakage of 45S rDNA loci. In both natural and resynthesized B. napus, we observed low rates of univalents, A-C bivalents, and early sister chromatid separations. Reciprocal homoeologous chromosome exchanges and double reductions were photographed for the first time in meiotic telophase I. Meiotic errors were non-uniformly distributed across the genome in resynthesized B. napus, and in particular homoeologs sharing synteny along their entire length exhibited multivalents at diakinesis and polysomic inheritance at telophase I. Natural B. napus appeared to resolve meiotic errors mainly by suppressing homoeologous pairing, resolving nonhomologous centromere associations and 45S rDNA associations before diakinesis, and reducing homoeologous cross-overs.

Selection and evaluation of reference genes for qRT-PCR of Scutellaria baicalensis Georgi under different experimental conditions.

Scutellaria baicalensis Georgi is a famous medicinal plant with its dried roots having been used as a traditional Chinese medicinal for more than 2000 years. Although its genome sequence has previously been published and molecular biology methods have been used to study this species, no suitable internal reference genes have been investigated for standardization of gene expression via quantitative real-time polymerase chain reaction (qRT-PCR). Here, the stabilities of 10 candidate reference genes, ACT11, ACT7, α-TUB, ß-TUB, GAPDH, UBC, RPL, SAM, HSP70, and PP2A, were analyzed by four different procedures of GeNorm, NormFinder, BestKeeper, and RefFinder. Their expression stabilities were evaluated under various conditions, including different tissue types (root, stem, leaf, and flower), hormone stimuli treatments (methyl jasmonate, salicylic acid, and abscisic acid), and abiotic stresses (heavy metal, salt, drought, cold, and wounding). The results indicated that ß-TUB was the most stable gene for all tested samples, while ACT11 was the most unstable. The most stable reference gene was not consistent under different conditions. ß-TUB exhibited the highest stability for different tissue types and abiotic stresses, while for hormone stimuli treatments, ACT7 showed the highest stability. To confirm the applicability of suitable reference genes, we selected to SbF6H and SbF8H as target genes to analyze their expression levels in different tissues. This study helps to the accurate quantification of the relative expression levels of interest genes in S. baicalensis via qRT-PCR analysis.

Effects of xanthan and konjac gums on pasting, rheology, microstructure, crystallinity and in vitro digestibility of mung bean resistant starch.

The effects of different concentrations of xanthan and konjac gums on the pasting, rheological properties, microstructure, crystallinity, and digestibility of mung bean resistant starch (MRS) were investigated. Based on the results of pasting properties, the adjunction of gums increased the peak, breakdown, and final viscosities of resistant starch. Compared with resistant starch, the addition of gum significantly increased the K value and dynamic moduli (G', G") of MRS with increasing gum concentration. This finding indicates that the mixtures had higher viscoelasticity. Mixtures with xanthan gum of MRS had larger starch particle compared with MRS, as revealed by SEM. All starches showed B and V-type crystallinity with high crystallinity. MRS had the highest summation of resistant starch (RS) and slowly digestible starch (SDS) of 71.89%. MRS had the lowest hydrolysis rate, which obviously decreased from 71.89% to 57.71% with increasing konjac gum from 0 to 0.30%.