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In the plant development cycle, different types of proteases play essential functions. Plant vacuolar processing enzymes (VPEs) are a group of cysteine proteases localized in the cell vacuoles that process and regulate several larger proprotein precursors. VPEs activate the proteolytic cleavage of proproteins precursors within aspartic acid and asparagine residues to trigger the tightly controlled programmed cell death process induced by different stages of plant development and environmental cues, impacting myriad plant physiological processes. In plants, VPEs are categorized into embryo, vegetative, and seed coat‐types, in which embryo and seed coat‐type VPEs are mainly involved in processing the seed storage protein precursors to provide nutrients for early growth, while the vegetative type induces programmed cell death in a varied range of vegetative tissues. Recently, several plant VPEs exhibited transpeptidase activity, which is essential for the cyclization mechanism during the production of cyclotides. In this review, we explore and understand the complex functions of plant VPEs, which can lead to the production of stress‐tolerant and higher‐yield crops, and provide the recent advances in the application of VPEs in molecular pharming, which highlights the significant implications of VPEs in protein science and agriculture. [ABSTRACT FROM AUTHOR]

Gibberellins (GAs) are a pervasive group of diterpene phytohormones. They can dominate various aspects of plant development and modulate plant phenotypic plasticity by crosstalking with multiple phytohormones. Studies on GA signaling illustrate that master negative regulator DELLA proteins regulate GAs and nearly all phytohormones' growth responses to sustain plant growth and defense under relentless biotic and abiotic stresses. The molecular mechanism of DELLA proteins in regulating GA‐sensitive growth in an integrated manner with multiple phytohormones became apparent recently. These studies describe the interaction of interaction DELLA proteins with a diverse group of transcriptional regulators and factors as well as nontranscriptional proteins in directing GA‐stimulated plant growth. In this review, we address the extensive recent work to delineate DELLA proteins and their interacting partners and summarize the latest evidence that DELLA proteins have a unique function in suppressing the GA‐related responses to sustain the tension among growth and defense. Core Ideas: This review summarizes the latest progress of GA signaling in plant development.This review highlights the pivotal role of DELLA proteins and their interacting targets in plant major developmental process.This study provides insights into how GA signaling integrates with multiple phytohormones and environmental cues.This study provides mechanistic understanding on how DELLA proteins sustain tension among growth and defense. [ABSTRACT FROM AUTHOR]

BRASSINAZOLE RESISTANT (BZR) are transcriptional factors that bind to the DNA of targeted genes to regulate several plant growth and physiological processes in response to abiotic and biotic stresses. However, information on such genes in Brassica napus is minimal. Furthermore, the new reference Brassica napus genome offers an excellent opportunity to systematically characterize this gene family in B. napus. In our study, 21 BnaBZR genes were distributed across 19 chromosomes of B. napus and clustered into four subgroups based on Arabidopsis thaliana orthologs. Functional divergence analysis among these groups evident the shifting of evolutionary rate after the duplication events. In terms of structural analysis, the BnaBZR genes within each subgroup are highly conserved but are distinctive within groups. Organ-specific expression analyses of BnaBZR genes using RNA-seq data and quantitative real-time polymerase chain reaction (qRT-PCR) revealed complex expression patterns in plant tissues during stress conditions. In which genes belonging to subgroups III and IV were identified to play central roles in plant tolerance to salt, drought, and Sclerotinia sclerotiorum stress. The insights from this study enrich our understanding of the B. napus BZR gene family and lay a foundation for future research in improving rape seed environmental adaptability. [ABSTRACT FROM AUTHOR]

Summary: Sclerotinia stem rot (SSR) caused by Sclerotinia sclerotiorum is a devastating disease of rapeseed (Brassica napus L.). To date, the genetic mechanisms of rapeseed' interactions with S. sclerotiorum are not fully understood, and molecular‐based breeding is still the most effective control strategy for this disease. Here, Arabidopsis thaliana GDSL1 was characterized as an extracellular GDSL lipase gene functioning in Sclerotinia resistance. Loss of AtGDSL1 function resulted in enhanced susceptibility to S. sclerotiorum. Conversely, overexpression of AtGDSL1 in B. napus enhanced resistance, which was associated with increased reactive oxygen species (ROS) and salicylic acid (SA) levels, and reduced jasmonic acid levels. In addition, AtGDSL1 can cause an increase in lipid precursor phosphatidic acid levels, which may lead to the activation of downstream ROS/SA defence‐related pathways. However, the rapeseed BnGDSL1 with highest sequence similarity to AtGDSL1 had no effect on SSR resistance. A candidate gene association study revealed that only one AtGDSL1 homolog from rapeseed, BnaC07g35650D (BnGLIP1), significantly contributed to resistance traits in a natural B. napus population, and the resistance function was also confirmed by a transient expression assay in tobacco leaves. Moreover, genomic analyses revealed that BnGLIP1 locus was embedded in a selected region associated with SSR resistance during the breeding process, and its elite allele type belonged to a minor allele in the population. Thus, BnGLIP1 is the functional equivalent of AtGDSL1 and has a broad application in rapeseed S. sclerotiorum‐resistance breeding. [ABSTRACT FROM AUTHOR]

Sclerotinia sclerotiorum (Lib.) de Bary is an unusual pathogen which has the broad host range, diverse infection modes, and potential double feeding lifestyles of both biotroph and necrotroph. It is capable of infecting over 400 plant species found worldwide and more than 60 names have agriculturally been used to refer to diseases caused by this pathogen. Plant defense to S. sclerotiorum is a complex biological process and exhibits a typical quantitative disease resistance (QDR) response. Recent studies using Arabidopsis thaliana and crop plants have obtained new advances in mechanisms used by plants to cope with S. sclerotiorum infection. In this review, we focused on our current understanding on plant defense mechanisms against this pathogen, and set up a model for the defense process including three stages: recognition of this pathogen, signal transduction and defense response. We also have a particular interest in defense signaling mediated by diverse signaling molecules. We highlight the current challenges and unanswered questions in both the defense process and defense signaling. Essentially, we discussed candidate resistance genes newly mapped by using high-throughput experiments in important crops, and classified these potential gene targets into different stages of the defense process, which will broaden our understanding of the genetic architecture underlying quantitative resistance to S. sclerotiorum. We proposed that more powerful mapping population(s) will be required for accurate and reliable QDR gene identification. [ABSTRACT FROM AUTHOR]

Brassica napus L. is an important oil crop worldwide and is the main raw material for biofuel. Seed weight and seed size are the main contributors to seed yield. DA1 (DA means big in Chinese) is an ubiquitin receptor and negatively regulates seed size. Down-regulation of AtDA1 in Arabidopsis leads to larger seeds and organs by increasing cell proliferation in integuments. In this study, BnDA1 was down-regulated in B. napus by over expressed of AtDA1 R358K, which is a functional deficiency of DA1 with an arginine-to-lysine mutation at the 358th amino acid. The results showed that the biomass and size of the seeds, cotyledons, leaves, flowers and siliques of transgenic plants all increased significantly. In particular, the 1000 seed weight increased 21.23% and the seed yield per plant increased 13.22% in field condition. The transgenic plants had no negative traits related to yield. The candidate gene association analysis demonstrated that the BnDA1 locus was contributed to the seeds weight. Therefore, our study showed that regulation of DA1 in B. napus can increase the seed yield and biomass, and DA1 is a promising target for crop improvement. [ABSTRACT FROM AUTHOR]

Introduction: Endothelium-derived molecules may be predictive to organ injury. Heat shock protein (HSP) A12B is mainly located in endothelial cells, which can be detected in the plasma of septic patients. Whether it is correlated with prognosis of sepsis remains unclear. Methods: Extracellular HSPA12B (eHSPA12B) was determined in plasma of septic mice at 6h, 12h, 24h and 48h after cecal ligation and puncture (CLP). It was also detected in plasma of patients with severe sepsis, sepsis, systemic inflammatory response syndrome and healthy volunteers. The predictive value for prognosis of severe sepsis was assessed by receiver operating curve (ROC) and Cox regression analyses. Results: eHSPA12B was elevated in plasma of CLP mice at 6h and peaked at 24h after surgery. A total of 118 subjects were included in the clinical section, including 66 patients with severe sepsis, 21 patients with sepsis, 16 patients with SIRS and 15 volunteers. Plasma eHSPA12B was significantly higher in patients with severe sepsis than in patients with sepsis, SIRS and volunteers. The level of eHSPA12B was also higher in non-survivals than survivals with severe sepsis. The area under the curve (AUC) of eHSPA12B in predicting death among patients with severe sepsis was 0.782 (0.654–0.909) in ROC analysis, much higher than that of IL-6 and IL-10. Cox regression analysis showed that cardiovascular diseases, IL-6 and eHSPA12B were risk factors for mortality in patients with severe sepsis. Survival curve demonstrated a strikingly significant difference between 28-day survival rates of patients with an eHSPA12B lower or not lower than 1.466ng/ml. Conclusions: Plasma eHSPA12B is elevated in both septic mice and patients. It may be a good predictor for poor outcome in patients with severe sepsis. [ABSTRACT FROM AUTHOR]

GDSL lipases form multigene families in Arabidopsis, rice and some other sequenced plant species. Unlike classical GxSxG motif-containing lipases, this new sub-family of lipolytic enzymes possesses a GDSL sequence motif (GDSxxDxG), and members are active in the hydrolysis and synthesis of a variety of lipids. Research on plant GDSL lipases started later than studies of microbial and animal GDSL lipases; therefore, our knowledge regarding plant GDSL lipases, from sequences to functional mechanisms, is limited. Recently, some GDSL lipase genes have been cloned and identified in different plant species. In this paper, we present a comprehensive review of the advances in research on plant GDSL lipases, which include their structures, distributions, biochemical activities, expression patterns and biological functions. Plant GDSL lipases have very flexible enzyme active sites, which can lead to extensive substrate binding and result in multifunctional properties. They play important roles in many physiological and biochemical processes, such as plant growth and development, organ morphogenesis, adversity stress and lipid metabolism. In addition, their potential applications in agriculture and industry are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Current biomarkers cannot completely distinguish sepsis from systemic inflammatory response syndrome (SIRS) caused by other non-infectious diseases. Circulating microRNAs (miRNAs) are promising biomarkers for several diseases, but their correlation with sepsis is not totally clarified. Methods: Seven miRNAs related to inflammation or infection were included in the present study. Serum miRNA expression was investigated in 50 patients diagnosed with sepsis, 30 patients with SIRS and 20 healthy controls to evaluate the diagnostic and prognostic value. Expression levels of serum miRNAs were determined by quantitative PCR using the Qiagen miScript system. Serum CRP and IL-6 levels were determined by enzyme linked immunosorbent assay. Results: Serum miR-146a and miR-223 were significantly reduced in septic patients compared with SIRS patients and healthy controls. The areas under the receiver operating characteristic curve of miR-146a, miR-223 and IL-6 were 0.858, 0.804 and 0.785, respectively. Conclusion: Serum miR-146a and miR-223 might serve as new biomarkers for sepsis with high specificity and sensitivity. (ClinicalTrials.gov number, NCT00862290.) [Copyright &y& Elsevier]

• BnaMPK6 plays an important role in defense to S. sclerotiorum. • The activation of ET signaling by BnaMPK6 may play a role in the defense. • BnaMPK6 is a previously unknown determinant of quantitative disease resistance (QDR) against S. sclerotiorum in B. napus. • BnaA03.MPK6 makes an important contribution to QDR against S. sclerotiorum in natural B. napus population. Sclerotinia sclerotiorum causes a devastating disease in oilseed rape (Brassica napus), resulting in major economic losses. Resistance response of B. napus against S. sclerotiorum exhibits a typical quantitative disease resistance (QDR) characteristic, but the molecular determinants of this QDR are largely unknown. In this study, we isolated a B. napus mitogen-activated protein kinase gene, BnaMPK6 , and found that BnaMPK6 expression is highly responsive to infection by S. sclerotiorum and treatment with salicylic acid (SA) or jasmonic acid (JA). Moreover, overexpression (OE) of BnaMPK6 significantly enhances resistance to S. sclerotiorum , whereas RNAi in BnaMPK6 significantly reduces this resistance. These results showed that BnaMPK6 plays an important role in defense to S. sclerotiorum. Furthermore, expression of defense genes associated with SA-, JA- and ethylene (ET)-mediated signaling was investigated in BnaMPK6 -RNAi, WT and BnaMPK6 -OE plants after S. sclerotiorum infection, and consequently, it was indicated that the activation of ET signaling by BnaMPK6 may play a role in the defense. Further, four BnaMPK6-encoding homologous loci were mapped in the B. napus genome. Using the allele analysis and expression analysis on the four loci, we demonstrated that the locus BnaA03.MPK6 makes an important contribution to QDR against S. sclerotiorum. Our data indicated that BnaMPK6 is a previously unknown determinant of QDR against S. sclerotiorum in B. napus. [ABSTRACT FROM AUTHOR]