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1.
Dalton Trans ; 53(18): 7669-7676, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38646797

ABSTRACT

A dinuclear Fe(II) spin crossover (SCO) complex with the formula [Fe2L5(NCS)4]·2DMF·2H2O (1) was synthesised from 1-naphthylimino-1,2,4-triazole (L). Complex 1 exhibits an incomplete thermally induced spin transition with a transition temperature T1/2 of 95 K and a thermally trapped metastable high-spin state at low temperatures. Furthermore, it undergoes a reversible light-induced spin crossover by alternate irradiation with 532 and 808 nm lasers.

2.
Small ; 20(8): e2304110, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37806756

ABSTRACT

Atherosclerosis (AS) is the primary reason behind cardiovascular diseases, leading to approximately one-third of global deaths. Developing a novel multi-model probe to detect AS is urgently required. Macrophages are the primary cells from which AS genesis occurs. Utilizing natural macrophage membranes coated on the surface of nanoparticles is an efficient delivery method to target plaque sites. Herein, Fe3 O4 -Cy7 nanoparticles (Fe3 O4 -Cy7 NPs), functionalized using an M2 macrophage membrane and a liposome extruder for Near-infrared fluorescence and Magnetic resonance imaging, are synthesized. These macrophage membrane-coated nanoparticles (Fe3 O4 @M2 NPs) enhance the recognition and uptake using active macrophages. Moreover, they inhibit uptake using inactive macrophages and human coronary artery endothelial cells. The macrophage membrane-coated nanoparticles (Fe3 O4 @M0 NPs, Fe3 O4 @M1 NPs, Fe3 O4 @M2 NPs) can target specific sites depending on the macrophage membrane type and are related to C-C chemofactor receptor type 2 protein content. Moreover, Fe3 O4 @M2 NPs demonstrate excellent biosafety in vivo after injection, showing a significantly higher Fe concentration in the blood than Fe3 O4 -Cy7 NPs. Therefore, Fe3 O4 @M2 NPs effectively retain the physicochemical properties of nanoparticles and depict reduced immunological response in blood circulation. These NPs mainly reveal enhanced targeting imaging capability for atherosclerotic plaque lesions.


Subject(s)
Atherosclerosis , Nanoparticles , Humans , Endothelial Cells , Nanoparticles/chemistry , Magnetic Resonance Imaging/methods , Atherosclerosis/diagnostic imaging
3.
ANZ J Surg ; 93(9): 2186-2191, 2023 09.
Article in English | MEDLINE | ID: mdl-37525364

ABSTRACT

BACKGROUND: Peritoneal malignancies are challenging cancers to manage. While cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS and HIPEC), may offer a cure, it is a radical procedure associated with significant morbidity. Pre-emptive identification of deconditioned patients for optimization may mitigate surgical risk. However, the difficulty lies in identifying a cost-effective predictive tool. Recently, there has been interest in sarcopenia, which may occur due to malignancy. The purpose of this study was to assess the utility of sarcopenia at predicting post-operative outcomes. METHODS: A quaternary-centre retrospective study of CRS and HIPEC patients (2017-2020), were conducted to determine the association between pre-operative sarcopenia on oncological (peritoneal carcinomatosis index (PCI)) and surgical outcomes (complications). Sarcopenia from lumbar CT-images were measured using Slice-o-matic™. Statistical differences were analysed using Mann-Whitney U and Chi-squared test. RESULTS: Cohort analysis (n = 94) found 40% had sarcopenia, majority were female (53.2%), and average age of 55 years. The major pathologies was colorectal cancer (n = 39, 41.5%), appendix adenocarcinoma (n = 21, 22.3%), and pseudomyxoma peritonei (PMP) (n = 19, 20.2%). Sarcopenia was associated with decreased weight, 72.7 versus 82.2 kg (P = 0.014) and shorter survival, 1.4 versus 2.1 years (95% CI, 1.09-3.05, P = 0.032). Median PCI (excluding PMP) was 11 (6-18) and median PCI (only PMP) was 25 (11-32). Post-operatively, sarcopenia patients experienced more complications (72.5% vs. 64.8%, P = 0.001). CONCLUSION: Pre-emptive identification of sarcopenia may be a useful prognostic indicator and predictor of post-operative outcomes in CRS and HIPEC. For oncological patients, sarcopenia may be an indicator of patients requiring targeted pre-operative rehabilitation, or advanced disease requiring further treatment.


Subject(s)
Hyperthermia, Induced , Pseudomyxoma Peritonei , Sarcopenia , Humans , Male , Female , Middle Aged , Hyperthermic Intraperitoneal Chemotherapy , Retrospective Studies , Cytoreduction Surgical Procedures/adverse effects , Cytoreduction Surgical Procedures/methods , Sarcopenia/diagnosis , Sarcopenia/etiology , Hyperthermia, Induced/adverse effects , Hyperthermia, Induced/methods , Combined Modality Therapy , Survival Rate , Antineoplastic Combined Chemotherapy Protocols/therapeutic use
4.
Chem Commun (Camb) ; 59(58): 8933-8936, 2023 Jul 18.
Article in English | MEDLINE | ID: mdl-37401807

ABSTRACT

Here, we demonstrate deep-blue carbon dots (CDs) with luminescence centered at 415 nm and PLQY exceeding 60% via nitrogen doping. A bright and high-color-purity CDs-based light-emitting diode (CLED) is achieved with an external quantum efficiency (EQE) of 1.74%, a maximum luminance of 1155.0 cd m-2, and a colour coordinate (0.16, 0.08) closely approaching the HDTV standard color Rec.BT.709 (0.15, 0.06) specification.

5.
Article in English | MEDLINE | ID: mdl-36231875

ABSTRACT

The need for family-friendly policies to balance work and life demands is growing. Many studies have addressed how family-friendly policies relate to a variety of employees' work attitudes and behavioral outcomes, but not how they (positively or negatively) affect them, especially the affective components of family-friendly policies that provide "felt" support to an employee. To fill this gap, this study adopts a moderated mediating mechanism to analyze how affective components of family-friendly policies impact employees' attitudes and behaviors through signaling and social exchange theory. We examined how this impact is mediated by factors such as work-life conflict, perceived organizational support, and control over working hours, as well as whether having a supportive supervisor moderates the mediated effect through further limiting the degree of work-life conflict or strengthening control over working hours. Data were collected through a survey with 401 employee-supervisor dyads from organizations in Hong Kong. We found that family-friendly policies do not necessarily affect work attitude and behavior, but they work through the sequential mediators of having more control over working hours and perceived organizational support. The role of supportive supervisors is also significant, in that they are likely to be key in molding the organizational environment for the gradual provision and uptake of family-friendly policies. The results of this study contribute to the development of signaling and social exchange theory and have theoretical implications for supervisors regarding them utilizing their position to improve employee work attitudes and behavioral outcomes.


Subject(s)
Attitude , Family Planning Policy , Hong Kong , Humans , Surveys and Questionnaires
6.
Int J Surg Case Rep ; 99: 107574, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36096081

ABSTRACT

INTRODUCTION AND IMPORTANCE: Necrotising soft tissue infections (NSTI) encompass a group of destructive soft tissue disease processes which can involve skin, subcutaneous tissue, fascia and or muscle, associated with rapid spread along tissue planes and mortality. Clinical presentations include progressive pain, suppuration/necrosis and systemic toxicity with haemodynamic instability. While diagnosis is based on clinical findings it can be augmented with imaging. Treatment is typically in the form of resuscitation, immediate administration of broad spectrum intravenous antibiotics and urgent source control through radical surgical debridement. CASE PRESENTATION: An 82-year-old man presented with left forearm/hand pain and fevers in the context of immunocompromise. Examination found tense swelling of the left volar and dorsal forearm and hand, absent distal pulses with pain and paraesthesia over both surfaces. He underwent surgical debridement with fasciotomy and remained in intensive care with blood cultures revealing ESBL E. coli. CLINICAL DISCUSSION: Compartment syndrome is a rare complication of NSTI and its clinical presentation can obscure early diagnosis. ESBL E. coli is an uncommon pathogen to cause monomicrobial infection and must be accounted for when considering broad spectrum empirical antibiotic cover. CONCLUSION: Review of this case and the literature show a rare presentation of NSTI and highlights the importance of early diagnosis based on even a small index of suspicion. It also shows the key significance rationalisation of antibiotics as soon as practicable, given that even broad spectrum empirical cover can be inappropriate in the context of novel microorganisms, particularly in high risk patients.

7.
Nanoscale ; 14(24): 8709-8726, 2022 Jun 23.
Article in English | MEDLINE | ID: mdl-35673987

ABSTRACT

Atherosclerosis, the leading cause of death in the elderly worldwide, is typically characterized by elevated reactive oxygen species (ROS) levels and a chronic inflammatory state at the arterial plaques. Herein, pH-sensitive nanoparticles (HRRAP NPs) co-delivering all-trans retinal (ATR), an antioxidant linked to hyaluronic acid (HA) through a pH-sensitive hydrazone bond, and rapamycin (RAP), an anti-atherosclerotic drug loaded into the nanoparticle core, are developed for targeted combination therapy of atherosclerosis. In this way, HRRAP NPs might simultaneously reduce ROS levels via ATR antioxidant activity and reduce inflammation via the anti-inflammatory effect of RAP. In response to mildly acidic conditions mimicking the lesional inflammation in vitro, HRRAP NPs dissociated and both ATR and RAP were effectively released. The developed HRRAP NPs effectively inhibited pro-inflammatory macrophage proliferation, and displayed dose- and time-dependent specific internalization by different cellular models of atherosclerosis. Also, HRRAP NP combination therapy showed an efficient synergetic anti-atherosclerotic effect in vitro by effectively inhibiting the inflammatory response and oxidative stress in inflammatory cells. More importantly, HR NPs specifically accumulated in the atherosclerotic plaques of apolipoprotein E-deficient (ApoE-/-) mice, by active interaction with HA receptors overexpressed by different cells of the plaque. The treatment with HRRAP NPs remarkably inhibited the progression of atherosclerosis in ApoE-/- mice which resulted in stable plaques with considerably smaller necrotic cores, lower matrix metalloproteinase-9, and decreased proliferation of macrophages and smooth muscle cells (SMCs). Furthermore, HRRAP NPs attenuated RAP adverse effects and exhibited a good safety profile after long-term treatment in mice. Consequently, the developed pH-sensitive HRRAP NP represent a promising nanoplatform for atherosclerosis combination therapy.


Subject(s)
Atherosclerosis , Nanoparticles , Plaque, Atherosclerotic , Animals , Apolipoproteins E , Atherosclerosis/drug therapy , Hyaluronic Acid/chemistry , Hydrogen-Ion Concentration , Inflammation/drug therapy , Mice , Mice, Inbred C57BL , Nanoparticles/chemistry , Plaque, Atherosclerotic/drug therapy , Reactive Oxygen Species , Retinaldehyde/therapeutic use , Sirolimus/pharmacology
8.
Pediatr Blood Cancer ; 69(3): e29415, 2022 03.
Article in English | MEDLINE | ID: mdl-34709700

ABSTRACT

PURPOSE: The aim of this study was to evaluate the diagnostic accuracy of 18 -fluorodeoxyglucose-positron emission tomography (18 F-FDG PET) and PET/computed tomography (PET/CT) in imaging primary and metastatic lesions in Ewing sarcoma (ES). METHODS: PubMed, Cochrane, Scopus, and Web of Science were searched for relevant studies. Data concerning 18 F-FDG PET/CT diagnostic accuracy were extracted and then analyzed using Open Meta-analyst software. Reported diagnostic accuracy outcomes included sensitivity, specificity, negative likelihood ratio (NLR), positive likelihood ratio (PLR), and diagnostic odds ratio. RESULTS: Thirty-one studies with a total of 735 patients were included in this meta-analysis. The sensitivity and specificity of 18 F-FDG PET/CT were: 92.6% and 74.1% for total ES lesions, 96.7% and 68.3% for ES primary lesions, 76.1% and 92.4% for lung metastasis, 83.9% and 93.2% for bone metastasis, and 89.9% and 92.6% for ES recurrence, respectively. CONCLUSION: 18 F-FDG PET/CT is sensitive and accurate in diagnosing, staging, and detecting the recurrence of ES compared with non-PET imaging. It has high accuracy for diagnosing recurrence of ES in bone metastases; however, CT remains a superior diagnostic method for detecting lung metastasis.


Subject(s)
Bone Neoplasms , Lung Neoplasms , Neuroectodermal Tumors, Primitive, Peripheral , Sarcoma, Ewing , Bone Neoplasms/pathology , Fluorodeoxyglucose F18 , Humans , Positron Emission Tomography Computed Tomography/methods , Positron-Emission Tomography , Radiopharmaceuticals , Sarcoma, Ewing/diagnostic imaging , Sarcoma, Ewing/pathology , Sensitivity and Specificity , Tomography, X-Ray Computed
9.
Res Social Adm Pharm ; 17(9): 1606-1613, 2021 09.
Article in English | MEDLINE | ID: mdl-33414090

ABSTRACT

INTRODUCTION: Community pharmacists are increasingly providing a range of professional health services. Whilst research provides evidence of their benefits, knowledge translation into practice has been challenging both in Australia and internationally. An opportunity to develop a granular understanding of factors driving successful implementation was presented by the Pharmacy Diabetes Screening Trial (PDST), a clustered Randomised Controlled Trial (RCT) implemented in a random sample of 339 Australian community pharmacies. Its aim was to compare the clinical and cost effectiveness of three pharmacy-based diabetes screening interventions. OBJECTIVE: To investigate the experiences of Australian community pharmacists in the implementation of the PDST and factors influencing implementation success. METHODS: Semi-structured telephone interviews were conducted with a stratified sample of pharmacist trial participants based on screening performance (number screened relative to target), location, and trial arm. All interviews were audio-recorded and transcribed ad verbatim. Interviews were continued until saturation. Initial thematic analysis was followed by in-depth analysis to test the extent to which the data fitted with three previously described overarching themes driving successful national implementation of innovation in community pharmacy. RESULTS: From August 2017 to October 2017, 21 interviews were conducted; 12 with high-performing and 9 with low-performing pharmacists. The key enablers and barriers were qualities of a pharmacy champion and active staff engagement, ease of implementation related to the number of working pharmacists and other staff, the external context including engagement with consumers and doctors, and consumer demand. It was also identified that attitudes/emphasis towards implementation planning and conscious prioritisation of service delivery by pharmacists may have been key differences between high- and low-performing pharmacies. CONCLUSION: Insights into the interaction between individual, organisational, and external factors influencing successful implementation of community pharmacy innovations highlighted in this study should inform the design of future innovations to ensure their success and sustainability.


Subject(s)
Community Pharmacy Services , Diabetes Mellitus , Pharmacies , Attitude of Health Personnel , Australia , Diabetes Mellitus/diagnosis , Diabetes Mellitus/drug therapy , Humans , Pharmacists , Professional Role
10.
Front Genet ; 11: 484, 2020.
Article in English | MEDLINE | ID: mdl-32457809

ABSTRACT

Dioscorea rotundata is an important food crop that is mainly cultivated in subtropical regions of the world. D. rotundata is frequently infected by various pathogens during its lifespan, which results in a substantial economic loss in terms of yield and quality. The disease resistance gene (R gene) profile of D. rotundata is largely unknown, which has greatly hampered molecular study of disease resistance in this species. Nucleotide-binding site-leucine-rich repeat (NBS-LRR) genes are the largest group of plant R genes, and they play important roles in plant defense responses to various pathogens. In this study, 167 NBS-LRR genes were identified from the D. rotundata genome. Subsequently, one gene was assigned to the resistance to powdery mildew8 (RPW8)-NBS-LRR (RNL) subclass and the other 166 genes to the coiled coil (CC)-NBS-LRR (CNL) subclass. None of the Toll/interleukin-1 receptor (TIR)-NBS-LRR (TNL) genes were detected in the genome. Among them, 124 genes are located in 25 multigene clusters and 43 genes are singletons. Tandem duplication serves as the major force for the cluster arrangement of NBS-LRR genes. Segmental duplication was detected for 18 NBS-LRR genes, although no whole-genome duplication has been documented for the species. Phylogenetic analysis revealed that D. rotundata NBS-LRR genes share 15 ancestral lineages with Arabidopsis thaliana genes. The NBS-LRR gene number increased by more than a factor of 10 during D. rotundata evolution. A conservatively evolved ancestral lineage was identified from D. rotundata, which is orthologs to the Arabidopsis RPM1 gene. Transcriptome analysis for four different tissues of D. rotundata revealed a low expression of most NBS-LRR genes, with the tuber and leaf displaying a relatively high NBS-LRR gene expression than the stem and flower. Overall, this study provides a complete set of NBS-LRR genes for D. rotundata, which may serve as a fundamental resource for mining functional NBS-LRR genes against various pathogens.

11.
Front Plant Sci ; 8: 1844, 2017.
Article in English | MEDLINE | ID: mdl-29123540

ABSTRACT

The Toll-interleukin-1 receptor (TIR) and Nucleotide-binding site (NBS) domains are two major components of the TIR-NBS-leucine-rich repeat family plant disease resistance genes. Extensive functional and evolutionary studies have been performed on these genes; however, the characterization of a small group of genes that are composed of atypical TIR and NBS domains, namely XTNX genes, is limited. The present study investigated this specific gene family by conducting genome-wide analyses of 59 green plant genomes. A total of 143 XTNX genes were identified in 51 of the 52 land plant genomes, whereas no XTNX gene was detected in any green algae genomes, which indicated that XTNX genes originated upon emergence of land plants. Phylogenetic analysis revealed that the ancestral XTNX gene underwent two rounds of ancient duplications in land plants, which resulted in the formation of clades I/II and clades IIa/IIb successively. Although clades I and IIb have evolved conservatively in angiosperms, the motif composition difference and sequence divergence at the amino acid level suggest that functional divergence may have occurred since the separation of the two clades. In contrast, several features of the clade IIa genes, including the absence in the majority of dicots, the long branches in the tree, the frequent loss of ancestral motifs, and the loss of expression in all detected tissues of Zea mays, all suggest that the genes in this lineage might have undergone pseudogenization. This study highlights that XTNX genes are a gene family originated anciently in land plants and underwent specific conservative pattern in evolution.

12.
G3 (Bethesda) ; 7(5): 1577-1585, 2017 05 05.
Article in English | MEDLINE | ID: mdl-28364035

ABSTRACT

Plant resistance conferred by nucleotide binding site (NBS)-encoding resistance genes plays a key role in the defense against various pathogens throughout the entire plant life cycle. However, comparative analyses for the systematic evaluation and determination of the evolutionary modes of NBS-encoding genes among Solanaceae species are rare. In this study, 447, 255, and 306 NBS-encoding genes were identified from the genomes of potato, tomato, and pepper, respectively. These genes usually clustered as tandem arrays on chromosomes; few existed as singletons. Phylogenetic analysis indicated that three subclasses [TNLs (TIR-NBS-LRR), CNLs (CC-NBS-LRR), and RNLs (RPW8-NBS-LRR)] each formed a monophyletic clade and were distinguished by unique exon/intron structures and amino acid motif sequences. By comparing phylogenetic and systematic relationships, we inferred that the NBS-encoding genes in the present genomes of potato, tomato, and pepper were derived from 150 CNL, 22 TNL, and 4 RNL ancestral genes, and underwent independent gene loss and duplication events after speciation. The NBS-encoding genes therefore exhibit diverse and dynamic evolutionary patterns in the three Solanaceae species, giving rise to the discrepant gene numbers observed today. Potato shows a "consistent expansion" pattern, tomato exhibits a pattern of "first expansion and then contraction," and pepper presents a "shrinking" pattern. The earlier expansion of CNLs in the common ancestor led to the dominance of this subclass in gene numbers. However, RNLs remained at low copy numbers due to their specific functions. Along the evolutionary process of NBS-encoding genes in Solanaceae, species-specific tandem duplications contributed the most to gene expansions.


Subject(s)
Evolution, Molecular , Gain of Function Mutation , Models, Genetic , Plant Proteins/genetics , Solanaceae/genetics , Binding Sites , Genetic Speciation , Loss of Function Mutation , Nucleotides/metabolism , Phylogeny , Plant Proteins/chemistry , Plant Proteins/metabolism , Protein Binding , Solanaceae/classification
13.
Front Plant Sci ; 7: 998, 2016.
Article in English | MEDLINE | ID: mdl-27458476

ABSTRACT

A major soybean (Forrest cultivar) quantitative trait locus (QTL) gene, Rhg4, which controls resistance to soybean cyst nematodes (SCN), encodes the enzyme serine hydroxylmethyltransferase (SHMT). The resistant allele possesses two critical missense mutations (P130R and N358Y) compared to that of the sensitive allele, rhg4. To understand the evolutionary history of this gene, sequences of 117 SHMT family members from 18 representative plant species were used to reconstruct their phylogeny. According to this phylogeny, the plant SHMT gene family can be divided into two groups and four subgroups (Ia, Ib, IIa, and IIb). Belonging to the Subgroup Ia lineage, the rhg4 gene evolved from a recent duplication event in Glycine sp.. To further explore how the SCN-resistant allele emerged, both the rhg4 gene and its closest homolog, the rhg4h gene, were isolated from 33 cultivated and 68 wild soybean varieties. The results suggested that after gene duplication, the soybean rhg4 gene accumulated a higher number of non-synonymous mutations than rhg4h. Although a higher number of segregating sites and gene haplotypes were detected in wild soybeans than in cultivars, the SCN-resistant Rhg4 allele (represented by haplotype 4) was not found in wild varieties. Instead, a very similar allele, haplotype 3, was observed in wild soybeans at a frequency of 7.4%, although it lacked the two critical non-synonymous substitutions. Taken together, these findings support that the SCN-resistant Rhg4 allele likely emerged via artificial selection during the soybean domestication process, based on a SCN-sensitive allele inherited from wild soybeans.

14.
Mol Biol Evol ; 33(8): 2044-53, 2016 08.
Article in English | MEDLINE | ID: mdl-27189569

ABSTRACT

Nucleotide insertions/deletions are ubiquitous in eukaryotic genomes, and the resulting hemizygous (unpaired) DNA has significant, heritable effects on adjacent DNA. However, little is known about the genetic behavior of insertion DNA. Here, we describe a binary transgenic system to study the behavior of insertion DNA during meiosis. Transgenic Arabidopsis lines were generated to carry two different defective reporter genes on nonhomologous chromosomes, designated as "recipient" and "donor" lines. Double hemizygous plants (harboring unpaired DNA) were produced by crossing between the recipient and the donor, and double homozygous lines (harboring paired DNA) via self-pollination. The transfer of the donor's unmutated sequence to the recipient generated a functional ß-glucuronidase gene, which could be visualized by histochemical staining and corroborated by polymerase chain reaction amplification and sequencing. More than 673 million seedlings were screened, and the results showed that meiotic ectopic recombination in the hemizygous lines occurred at a frequency >6.49-fold higher than that in the homozygous lines. Gene conversion might have been exclusively or predominantly responsible for the gene correction events. The direct measurement of ectopic recombination events provided evidence that an insertion, in the absence of an allelic counterpart, could scan the entire genome for homologous counterparts with which to pair. Furthermore, the unpaired (hemizygous) architectures could accelerate ectopic recombination between itself and interchromosomal counterparts. We suggest that the ectopic recombination accelerated by hemizygous architectures may be a general mechanism for interchromosomal recombination through ubiquitously dispersed repeat sequences in plants, ultimately contributing to genetic renovation and eukaryotic evolution.


Subject(s)
Arabidopsis/genetics , DNA, Plant/genetics , Mutagenesis, Insertional , Arabidopsis/metabolism , Chromosomes , Crossing Over, Genetic , Gene Conversion , Hemizygote , Homologous Recombination , Homozygote , Meiosis/genetics , Plants, Genetically Modified , Recombination, Genetic , Seedlings
15.
Front Plant Sci ; 7: 429, 2016.
Article in English | MEDLINE | ID: mdl-27066061

ABSTRACT

A majority of land plants can form symbiosis with arbuscular mycorrhizal (AM) fungi. MicroRNAs (miRNAs) have been implicated to regulate this process in legumes, but their involvement in non-legume species is largely unknown. In this study, by performing deep sequencing of sRNA libraries in tomato roots and comparing with tomato genome, a total of 700 potential miRNAs were predicted, among them, 187 are known plant miRNAs that have been previously deposited in miRBase. Unlike the profiles in other plants such as rice and Arabidopsis, a large proportion of predicted tomato miRNAs was 24 nt in length. A similar pattern was observed in the potato genome but not in tobacco, indicating a Solanum genus-specific expansion of 24-nt miRNAs. About 40% identified tomato miRNAs showed significantly altered expressions upon Rhizophagus irregularis inoculation, suggesting the potential roles of these novel miRNAs in AM symbiosis. The differential expression of five known and six novel miRNAs were further validated using qPCR analysis. Interestingly, three up-regulated known tomato miRNAs belong to a known miR171 family, a member of which has been reported in Medicago truncatula to regulate AM symbiosis. Thus, the miR171 family likely regulates AM symbiosis conservatively across different plant lineages. More than 1000 genes targeted by potential AM-responsive miRNAs were provided and their roles in AM symbiosis are worth further exploring.

16.
Plant Physiol ; 170(4): 2095-109, 2016 04.
Article in English | MEDLINE | ID: mdl-26839128

ABSTRACT

Nucleotide-binding site-leucine-rich repeat (NBS-LRR) genes make up the largest plant disease resistance gene family (R genes), with hundreds of copies occurring in individual angiosperm genomes. However, the expansion history of NBS-LRR genes during angiosperm evolution is largely unknown. By identifying more than 6,000 NBS-LRR genes in 22 representative angiosperms and reconstructing their phylogenies, we present a potential framework of NBS-LRR gene evolution in the angiosperm. Three anciently diverged NBS-LRR classes (TNLs, CNLs, and RNLs) were distinguished with unique exon-intron structures and DNA motif sequences. A total of seven ancient TNL, 14 CNL, and two RNL lineages were discovered in the ancestral angiosperm, from which all current NBS-LRR gene repertoires were evolved. A pattern of gradual expansion during the first 100 million years of evolution of the angiosperm clade was observed for CNLs. TNL numbers remained stable during this period but were eventually deleted in three divergent angiosperm lineages. We inferred that an intense expansion of both TNL and CNL genes started from the Cretaceous-Paleogene boundary. Because dramatic environmental changes and an explosion in fungal diversity occurred during this period, the observed expansions of R genes probably reflect convergent adaptive responses of various angiosperm families. An ancient whole-genome duplication event that occurred in an angiosperm ancestor resulted in two RNL lineages, which were conservatively evolved and acted as scaffold proteins for defense signal transduction. Overall, the reconstructed framework of angiosperm NBS-LRR gene evolution in this study may serve as a fundamental reference for better understanding angiosperm NBS-LRR genes.


Subject(s)
Evolution, Molecular , Genes, Plant , Genetic Variation , Magnoliopsida/genetics , NLR Proteins/genetics , Arabidopsis/genetics , Base Sequence , Binding Sites , Exons/genetics , Introns/genetics , Nucleotide Motifs/genetics , Phylogeny , Species Specificity
17.
J Integr Plant Biol ; 58(2): 165-77, 2016 Feb.
Article in English | MEDLINE | ID: mdl-25926337

ABSTRACT

Plant genomes harbor dozens to hundreds of nucleotide-binding site-leucine-rich repeat (NBS-LRR) genes; however, the long-term evolutionary history of these resistance genes has not been fully understood. This study focuses on five Brassicaceae genomes and the Carica papaya genome to explore changes in NBS-LRR genes that have taken place in this Rosid II lineage during the past 72 million years. Various numbers of NBS-LRR genes were identified from Arabidopsis lyrata (198), A. thaliana (165), Brassica rapa (204), Capsella rubella (127), Thellungiella salsuginea (88), and C. papaya (51). In each genome, the identified NBS-LRR genes were found to be unevenly distributed among chromosomes and most of them were clustered together. Phylogenetic analysis revealed that, before and after Brassicaceae speciation events, both toll/interleukin-1 receptor-NBS-LRR (TNL) genes and non-toll/interleukin-1 receptor-NBS-LRR (nTNL) genes exhibited a pattern of first expansion and then contraction, suggesting that both subclasses of NBS-LRR genes were responding to pathogen pressures synchronically. Further, by examining the gain/loss of TNL and nTNL genes at different evolutionary nodes, this study revealed that both events often occurred more drastically in TNL genes. Finally, the phylogeny of nTNL genes suggested that this NBS-LRR subclass is composed of two separate ancient gene types: RPW8-NBS-LRR and Coiled-coil-NBS-LRR.


Subject(s)
Brassicaceae/genetics , Evolution, Molecular , Genes, Plant , Nucleotides/metabolism , Plant Proteins/genetics , Proteins/genetics , Binding Sites , Chromosome Mapping , Chromosomes, Plant/genetics , Gene Duplication , Genetic Loci , Leucine-Rich Repeat Proteins , Likelihood Functions , Multigene Family , Phylogeny , Species Specificity , Synteny/genetics
18.
Mol Genet Genomics ; 291(2): 739-52, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26563433

ABSTRACT

Very long-chain fatty acids (VLCFAs) play an important role in the survival and development of plants, and VLCFA synthesis is regulated by ß-ketoacyl-CoA synthases (KCSs), which catalyze the condensation of an acyl-CoA with malonyl-CoA. Here, we present a genome-wide survey of the genes encoding these enzymes, KCS genes, in 28 species (26 genomes and two transcriptomes), which represents a large phylogenetic scale, and also reconstruct the evolutionary history of this gene family. KCS genes were initially single-copy genes in the green plant lineage; duplication resulted in five ancestral copies in land plants, forming five fundamental monophyletic groups in the phylogenetic tree. Subsequently, KCS genes duplicated to generate 11 genes of angiosperm origin, expanding up to 20-30 members in further-diverged angiosperm species. During this process, tandem duplications had only a small contribution, whereas polyploidy events and large-scale segmental duplications appear to be the main driving force. Accompanying this expansion were variations that led to the sub- and neofunctionalization of different members, resulting in specificity that is likely determined by the 3-D protein structure. Novel functions involved in other physiological processes emerged as well, though redundancy is also observed, largely among recent duplications. Conserved sites and variable sites of KCS proteins are also identified by statistical analysis. The variable sites are likely to be involved in the emergence of product specificity and catalytic power, and conserved sites are possibly responsible for the preservation of fundamental function.


Subject(s)
3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/genetics , Evolution, Molecular , Multigene Family/genetics , Phylogeny , Amino Acid Sequence , Gene Duplication , Genome, Plant , Magnoliopsida/genetics , Polyploidy , Transcriptome/genetics
19.
Zhongguo Zhong Yao Za Zhi ; 40(2): 218-25, 2015 Jan.
Article in Chinese | MEDLINE | ID: mdl-26080548

ABSTRACT

To offer the reference and method for salt damage in the cultivation of Marsdenia tenacissima, the seeds of M. tenacissima collected from Maguan city ( Yunnan province) were taken as the test materials to study the effects of different priming materials on improving germination and growth under high-level salt stress condition. Four different treatments, which were GA3, KNO3-KH2PO4, PEG-6000, NaCl, combined with ANOVA were applied to test the performance of germination energy, germination percentage, germination index, MDA, SOD, and CAT. The results showed that the seed germination was obviously inhibited under salt stress and the soaked seeds with different priming materials could alleviate the damage of salt stress. Under these treatments, the activities of SOD, CAT the content of soluble protein significantly increased. While the content of MDA significantly decreased. The maximum index was obtained when treated with 1.20% KNO3-KH2PO4, the germination percentage increased from 52.67% to 87.33% and the activity of SOD increased from 138.01 to 219.44 respectively. Comparing with the treatment of 1.20% KNO3-KH2PO4, the germination percentage of treating with 300 mg x L(-1) GA3 increased from 52.67% to 80.67%, while the activity of SOD increased from 138.01 to 444.61.


Subject(s)
Germination/physiology , Marsdenia/growth & development , Sodium Chloride/pharmacology , Germination/drug effects , Marsdenia/drug effects , Nitrates/pharmacology , Polyethylene Glycols/pharmacology , Potassium Compounds/pharmacology , Seeds/drug effects , Seeds/growth & development , Stress, Physiological , Xanthones/pharmacology
20.
Virus Res ; 191: 125-33, 2014 Oct 13.
Article in English | MEDLINE | ID: mdl-25107622

ABSTRACT

Widely known as a severe pathogen of bean plants, the bean common mosaic virus (BCMV) has been reported to infect soybeans only sporadically and the involved strains were all found in China regions. To explore variations among soybean-infecting BCMV strains, hundreds of soybean mosaic leave samples were collected throughout China, with a total of 30 BCMV isolates detected and their genomes sequenced. These newly obtained genomes, together with 16 other BCMV genomes available in GenBank were examined from multiple aspects to characterize BCMV evolutionary processes. Phylogenetic analysis showed that both soybean-infecting BCMVs (group I) and peanut-infecting BCMVs (group II) are distantly related to other BCMVs, suggesting ancestral differentiation and host adaptation. Genetic variation analysis showed that P1, P3 and 6K2 genes and the beginning portion of CP gene showed higher levels of variation relative to other genes. Moreover, selection analyses further confirmed that a number of sites within the P1 and P3 genes have suffered positive selection. These obtained BCMV sequences also exhibit high recombination frequencies, indicating a more dynamic evolutionary history. Finally, 12 different soybean cultivars were challenged with two BCMV isolates (DXH015 and HZZB011), with most of the cultivars successfully infected. These findings suggest that BCMV is indeed a potential threat to soybean production.


Subject(s)
Genome, Viral , Glycine max/virology , Plant Diseases/virology , Potyvirus/isolation & purification , China , Genomics , Molecular Sequence Data , Phylogeny , Potyvirus/classification , Potyvirus/genetics , Viral Proteins/genetics
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