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1.
Am Heart J ; 274: 46-53, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38710379

RESUMEN

BACKGROUND: Previous studies suggested only the radial artery and the No-touch (NT) technique were effective in reducing graft occlusion after coronary artery bypass grafting (CABG) surgery. However, there is no randomized trial comparing these 2 graft conduits. The optimum second conduit for CABG remains undetermined. MATERIALS AND METHODS: This study is a prospective, single-center randomized clinical trial, aiming to compare the graft patency between the radial artery and the NT vein graft. All patients undergoing isolated CABG with left internal mammary artery (LIMA) plus at least 2 additional grafts will be considered eligible. About 774 cases (516 in the radial artery group and 258 in the NT vein group) will be enrolled in over 1 to 2 years. Participants will be randomized and allocated to two bypass strategies: the LIMA plus 1 radial artery and 1 conventional vein graft, or the LIMA plus 2 NT vein grafts. The primary outcome is graft occlusion at 1 year after CABG evaluated by CT angiography. The secondary outcomes include graft occlusion at 3 and 5 years and major adverse cardiac or cerebrovascular events at 1, 3, and 5 years follow-ups. DISCUSSION: This study will define whether or not the NT vein has a lower graft occlusion rate than the radial artery in short and mid-term follow-ups, and provide new evidence for the second conduit choice in CABG surgery. TRIAL REGISTRATION: ClinicalTrials.gov NCT06014047. Registered on October 15th, 2023.


Asunto(s)
Puente de Arteria Coronaria , Oclusión de Injerto Vascular , Arteria Radial , Vena Safena , Grado de Desobstrucción Vascular , Humanos , Arteria Radial/trasplante , Puente de Arteria Coronaria/métodos , Puente de Arteria Coronaria/efectos adversos , Vena Safena/trasplante , Oclusión de Injerto Vascular/prevención & control , Oclusión de Injerto Vascular/etiología , Estudios Prospectivos , Femenino , Masculino , Persona de Mediana Edad , Enfermedad de la Arteria Coronaria/cirugía , Arterias Mamarias/trasplante , Anciano , Ensayos Clínicos Controlados Aleatorios como Asunto , Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos
2.
Cerebrovasc Dis ; 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38253035

RESUMEN

OBJECTIVE: Aim of the present article was the demonstration of the institutional experience with the endovascular management of the anterior inferior cerebellar artery (AICA) aneurysms in order to propose a treatment algorithm. METHODS: Clinical data were obtained from 33 patients with 37 AICA aneurysms who had been surgically treated at the authors' hospital between 2010 and 2022. The patients' medical records, imaging data, and follow-up outcomes were retrospectively analyzed. RESULTS: All 33 patients (10 males, 23 females; mean age 54.88±12.49 years) underwent endovascular therapy for AICA aneurysms. The most common chief complaints were headache (87.9%), nausea and vomiting (57.6%), and alteration of consciousness (27.3%). 31 patients experienced subarachnoid hemorrhage (SAH). Regarding the AICA aneurysm location, 23 aneurysms were found at the right side of AICA in DSA images, and there were 6, 9, 16, 6 aneurysms in segments A1-A4, respectively. Coiling (59.5%), Onyx embolization (29.7%), coiling-combined Onyx embolization (5.4%), non-intervention (5.4%) were chosen in the surgical strategy. The length of follow-up was 8.09±5.05 months, and 84.8% of the patients had favorable modified Rankin Scale (mRS) scores. The complete occlusion rates were 94.6%. Postoperative complications occurred in 4 cases (12.1 %), including new neurological deficit in 3 cases and cerebral infarction in 1 case. 1 patient died after follow-up because of the severe pneumonia. Poor initial Hunt and Hess grade (HHG) (p=0.007) was the risk factor for unfavorable clinical outcome. The rupture status (p=0.025) and the location (p=0.021) of the AICA aneurysms are statistically significant in determining which operation strategy to be chosen. Coiling had an advantage over Onyx embolization (P=0.001) in parent artery preservation (PAP). CONCLUSIONS: In this study, an algorithm for the treatment of AICA aneurysms was proposed based on the clinical status of the patients before treatment, the anatomical factors of AICA and the technical conditions of EVT. To our knowledge, this is the first study to report more than 30 cases of AICA aneurysms that had been treated by EVT and to advocate a treatment algorithm. EVT of AICA aneurysms is an optional strategy, but decisions are made based on the specific condition, anatomical location and other factors.

3.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38473815

RESUMEN

Heterosis plays a significant role in enhancing variety, boosting yield, and raising economic value in crops, but the molecular mechanism is still unclear. We analyzed the transcriptomes and 3D genomes of a hybrid (F1) and its parents (w30 and 082). The analysis of the expression revealed a total of 485 specially expressed genes (SEGs), 173 differentially expressed genes (DEGs) above the parental expression level, more actively expressed genes, and up-regulated DEGs in the F1. Further study revealed that the DEGs detected in the F1 and its parents were mainly involved in the response to auxin, plant hormone signal transduction, DNA metabolic process, purine metabolism, starch, and sucrose metabolism, which suggested that these biological processes may play a crucial role in the heterosis of Brassica rapa. The analysis of 3D genome data revealed that hybrid F1 plants tend to contain more transcriptionally active A chromatin compartments after hybridization. Supplementaryly, the F1 had a smaller TAD (topologically associated domain) genome length, but the number was the highest, and the expression change in activated TAD was higher than that of repressed TAD. More specific TAD boundaries were detected between the parents and F1. Subsequently, 140 DEGs with genomic structural variants were selected as potential candidate genes. We found two DEGs with consistent expression changes in A/B compartments and TADs. Our findings suggested that genomic structural variants, such as TADs and A/B chromatin compartments, may affect gene expression and contribute to heterosis in Brassica rapa. This study provides further insight into the molecular mechanism of heterosis in Brassica rapa.


Asunto(s)
Brassica rapa , Cromatina , Vigor Híbrido , Hibridación Genética , Expresión Génica , Regulación de la Expresión Génica de las Plantas , Perfilación de la Expresión Génica
4.
Plant J ; 111(1): 134-148, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35442527

RESUMEN

Drought stress triggers the accumulation of the phytohormone abscisic acid (ABA), which in turn activates the expression of the floral integrator gene CONSTANS (CO), accelerating flowering. However, the molecular mechanism of ABA-induced CO activation remains elusive. Here, we conducted a yeast one-hybrid assay using the CO promoter from Brassica campestris (syn. Brassica rapa) ssp. chinensis (pak choi) to screen the ABA-induced pak choi library and identified the transcription activator ABF3 (BrABF3). BrABF3, the expression of which was induced by ABA in pak choi, directly bound to the CO promoter from both pak choi and Arabidopsis. The BrABF3 promoter is specifically active in the Arabidopsis leaf vascular tissue, where CO is mainly expressed. Impaired BrABF3 expression in pak choi decreased BrCO expression levels and delayed flowering, whereas ectopic expression of BrABF3 in Arabidopsis increased CO expression and induced earlier flowering under the long-day conditions. Electrophoretic mobility shift assay analysis showed that BrABF3 was enriched at the canonical ABA-responsive element-ABRE binding factor (ABRE-ABF) binding motifs of the BrCO promoter. The direct binding of BrABF3 to the ABRE elements of CO was further confirmed by chromatin immunoprecipitation quantitative PCR. In addition, the induction of BrCO transcription by BrABF3 could be repressed by BrCDF1 in the morning. Thus, our results suggest that ABA could accelerate the floral transition by directly activating BrCO transcription through BrABF3 in pak choi.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Brassica rapa , Ácido Abscísico/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassica rapa/genética , Brassica rapa/metabolismo , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
5.
Int J Mol Sci ; 24(15)2023 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-37569388

RESUMEN

Rice chromosomal segment substitution lines (CSSLs) are ideal materials for studying quantitative traits such as grain size. Here, a rice large-grain CSSL-Z403 was identified among progeny of the recipient Xihui18 and the donor Jinhui35 based on molecular marker-assisted selection. Z403 carried 10 substitution segments with average length of 3.01 Mb. Then, a secondary F2 population derived from a cross between Xihui18 and Z403 was used to map quantitative trait loci (QTL) for grain size. Six QTLs distributed on chromosomes 5, 6, 7, 9 and 12 were detected. Finally four single-segment substitution lines (SSSLs) and two dual-segment substitution lines (DSSLs) carrying these target QTLs were constructed, and 10 novel QTLs were identified by four SSSLs. The large grain of Z403 was controlled at least by qGWT5, qGWT7, qGWT9 and qGWT12, and its grain weight was influenced through grain length QTL such as qGL5, qGL6, qGL9 and qGL12, as well as grain width QTL such as qGW5, qGW7, qGW9 and qGW12. Among 16 QTLs, four QTLs including qGL6, etc., might be novel compared with the reported documents. Again, positive or less negative epistatic effects between two non-allelic QTLs (additive effect > 0) may assist screening the genotype with larger grain size in further selection.

6.
Int J Mol Sci ; 24(18)2023 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-37762111

RESUMEN

Hypocotyl length is a critical determinant for the efficiency of mechanical harvesting in pakchoi production, but the knowledge on the molecular regulation of hypocotyl growth is very limited. Here, we report a spontaneous mutant of pakchoi, lhy7.1, and identified its characteristics. We found that it has an elongated hypocotyl phenotype compared to the wild type caused by the longitudinal growth of hypocotyl cells. Different light quality treatments, transcriptome, and proteomic analyses were performed to reveal the molecular mechanisms of hypocotyl elongation. The data showed that the hypocotyl length of lhy7.1 was significantly longer than that of WT under red, blue, and white lights but there was no significant difference under dark conditions. Furthermore, we used transcriptome and label-free proteome analyses to investigate differences in gene and protein expression levels between lhy7.1 and WT. At the transcript level, 4568 differentially expressed genes (DEGs) were identified, which were mainly enriched in "plant hormone signal transduction", "photosynthesis", "photosynthesis-antenna proteins", and "carbon fixation in photosynthetic organisms" pathways. At the protein level, 1007 differentially expressed proteins (DEPs) were identified and were mainly enriched in photosynthesis-related pathways. The comprehensive transcriptome and proteome analyses revealed a regulatory network of hypocotyl elongation involving plant hormone signal transduction and photosynthesis-related pathways. The findings of this study help elucidate the regulatory mechanisms of hypocotyl elongation in lhy7.1.


Asunto(s)
Hipocótilo , Proteoma , Proteoma/genética , Hipocótilo/genética , Reguladores del Crecimiento de las Plantas , Proteómica , Transcriptoma
7.
Circulation ; 144(14): 1120-1129, 2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-34510911

RESUMEN

BACKGROUND: Vein graft occlusion is deemed a major challenge in coronary artery bypass grafting. Previous studies implied that the no-touch technique for vein graft harvesting could reduce occlusion rate compared with the conventional approach; however, evidence on the clinical benefit and generalizability of the no-touch technique is scare. METHODS: From April 2017 to June 2019, we randomly assigned 2655 patients undergoing coronary artery bypass grafting at 7 hospitals in a 1:1 ratio to receive no-touch technique or conventional approach for vein harvesting. The primary outcome was vein graft occlusion on computed tomography angiography at 3 months and the secondary outcomes included 12-month vein graft occlusion, recurrence of angina, and major adverse cardiac and cerebrovascular events. The generalized estimate equation model was used to account for the cluster effect of grafts from the same patient. RESULTS: During the follow-up, 2533 (96.0%) participants received computed tomography angiography at 3 months after coronary artery bypass grafting and 2434 (92.2%) received it at 12 months. The no-touch group had significantly lower rates of vein graft occlusion than the conventional group both at 3 months (2.8% versus 4.8%; odds ratio, 0.57 [95% CI, 0.41-0.80]; P<0.001) and 12 months (3.7% versus 6.5%; odds ratio, 0.56 [95% CI, 0.41-0.76]; P<0.001). Recurrence of angina was also less common in the no-touch group at 12 months (2.3% versus 4.1%; odds ratio, 0.55 [95% CI, 0.35-0.85]; P<0.01). Rates of major adverse cardiac and cerebrovascular events were of no significant difference between the 2 groups. The no-touch technique was associated with higher rates of leg wound surgical interventions at 3-month follow-up (10.3% versus 4.3%; odds ratio, 2.55 [95% CI, 1.85-3.52]; P<0.001). CONCLUSIONS: Compared with the conventional vein harvesting approach in coronary artery bypass grafting, the no-touch technique significantly reduced the risk of vein graft occlusion and improved patient prognosis. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03126409.


Asunto(s)
Puente de Arteria Coronaria/métodos , Procedimientos Quirúrgicos Vasculares/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Resultado del Tratamiento
8.
Plant Mol Biol ; 109(6): 741-759, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35553313

RESUMEN

WRKY transcription factors play important roles in abiotic stress by directly regulating stress-related genes. However, the molecular mechanism of its involvement in salt stress in pak-choi is still poorly understood. In this study, we elucidated the function of BcWRKY1 from pak-choi (Brassica rapa ssp. chinensis) in salt stress. The expression level of BcWRKY1 showed the highest in rosette leaves among different tissues and was induced by salt and ABA treatment in pak-choi. Subcellular localization showed that BcWRKY1 was located in nucleus. The transgenic Arabidopsis overexpressing BcWRKY1 exhibited enhanced salt sensitivity and higher H2O2 contents, which were further confirmed by silencing BcWRKY1 in pak-choi. In addition, the expression of ZAT12 was negatively regulated with BcWRKY1 under salt stress both in pak-choi and Arabidopsis. Yeast one-hybrid and dual luciferase reporter assay showed that BcWRKY1 could bind to the promoter of BcZAT12, and BcsAPX expression was activated by BcZAT12. To sum up, we propose a BcWRKY1-BcZAT12-BcsAPX regulatory model that involves in pak-choi salt stress response.


Asunto(s)
Arabidopsis , Hipertensión , Arabidopsis/genética , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Peróxido de Hidrógeno/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo
9.
Plant Physiol ; 186(1): 388-406, 2021 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-33599732

RESUMEN

Ethiopian mustard (Brassica carinata) in the Brassicaceae family possesses many excellent agronomic traits. Here, the high-quality genome sequence of B. carinata is reported. Characterization revealed a genome anchored to 17 chromosomes with a total length of 1.087 Gb and an N50 scaffold length of 60 Mb. Repetitive sequences account for approximately 634 Mb or 58.34% of the B. carinata genome. Notably, 51.91% of 97,149 genes are confined to the terminal 20% of chromosomes as a result of the expansion of repeats in pericentromeric regions. Brassica carinata shares one whole-genome triplication event with the five other species in U's triangle, a classic model of evolution and polyploidy in Brassica. Brassica carinata was deduced to have formed ∼0.047 Mya, which is slightly earlier than B. napus but later than B. juncea. Our analysis indicated that the relationship between the two subgenomes (BcaB and BcaC) is greater than that between other two tetraploid subgenomes (BjuB and BnaC) and their respective diploid parents. RNA-seq datasets and comparative genomic analysis were used to identify several key genes in pathways regulating disease resistance and glucosinolate metabolism. Further analyses revealed that genome triplication and tandem duplication played important roles in the expansion of those genes in Brassica species. With the genome sequencing of B. carinata completed, the genomes of all six Brassica species in U's triangle are now resolved. The data obtained from genome sequencing, transcriptome analysis, and comparative genomic efforts in this study provide valuable insights into the genome evolution of the six Brassica species in U's triangle.


Asunto(s)
Evolución Biológica , Brassica/genética , Genoma de Planta , Poliploidía , Modelos Biológicos
10.
Phytopathology ; 112(12): 2523-2537, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35852468

RESUMEN

In plants, the salicylic acid (SA) and jasmonic acid (JA) signaling pathways usually mediate the defense response to biotrophic and necrotrophic pathogens, respectively. Our previous work showed that after non-heading Chinese cabbage (NHCC) was infected with the biotrophic pathogen Hyaloperonospora parasitica, expression of the JA biosynthetic gene BcOPR3 is induced; however, its molecular mechanism remains unclear. Here, we overexpressed BcOPR3 in Arabidopsis and silenced BcOPR3 in NHCC001 plants to study the defensive role of BcOPR3 in plants against pathogen invasion. The results showed that overexpression of BcOPR3 increased the susceptibility of Arabidopsis to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) but enhanced its resistance to Botrytis cinerea. BcOPR3-silenced NHCC001 plants with a 50% reduction in BcOPR3 expression increased their resistance to downy mildew by reducing the hyphal density and spores of H. parasitica. In addition, BcOPR3-partly silenced NHCC001 plants were also resistant to B. cinerea, which could be the result of a synergistic effect of JA and SA. These findings indicate a complicated role of BcOPR3 in the mediating defense responses to biotrophic and necrotrophic pathogens.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Oomicetos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Botrytis/fisiología , Ciclopentanos/metabolismo , Regulación de la Expresión Génica de las Plantas , Oxilipinas/metabolismo , Enfermedades de las Plantas/genética , Pseudomonas syringae , Ácido Salicílico/metabolismo
11.
Appl Opt ; 61(3): 844-850, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-35200793

RESUMEN

The discovery of monolayer graphene allows the unprecedented chance for exploring its Goos-Hänchen (GH) shift. However, most of the pronounced GH shifts are achieved in various structures with two-dimensional continuous monolayer graphene. Here, we report on the giant GH shift of reflected wave in monolayer graphene strips by constructing the multilayer dielectric grating structure under them. The observed GH shift here is as high as 7000 times that of the incident wave at the near-infrared frequency region, whose magnification is significantly larger than that of the monolayer graphene ribbon array. We further elucidate that the enhanced GH shift originates from the guided mode resonance of the dielectric grating structure and its magnitude and sign can be manipulated by chemical potential of the monolayer graphene strip. Our work enables a promising route for enhancing and controlling the GH shifts of reflected wave in monolayer graphene strips, which might contribute to their applications in biosensors and detectors.

12.
Neurosurg Rev ; 45(6): 3789-3800, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36326984

RESUMEN

Treating blood blister-like aneurysms (BBA) is a major neurosurgical challenge. Whether endovascular repair serves as a better strategy than microsurgery remains controversial. We aim to perform a propensity score-matched (PSM) retrospective study to analyze the short-term outcome in BBA patients who received microsurgery and endovascular treatment. One hundred fifty-five eligible patients with internal carotid artery BBA were retrospectively collected with demographic and angiographic baseline in a single center. Three-month outcome and adverse events were set as outcome endpoints. PSM was used to match the microsurgery and endovascular group. Matching effect was evaluated by distribution variation analysis and love plot. The outcome of neurosurgery and endovascular treatment was then compared before and after PSM. Better WFNS levels (p = .017) and modified Fisher grade (p = .027) were noted in endovascular group before matching. Other baseline including angiographic features were comparable between two groups. Before matching, the 3-month outcome of endovascular repair surgery was more favorable than microsurgery (p < .0001). The occurrence of adverse events was also higher in the microsurgery group (p = .0079). In PSM-adjusted groups, the superior outcome effect of endovascular treatment still existed but with a reduced significance (p = .004). Similar trend was also observed in the adverse event rate (p = .038). Fatality rate was comparable between two adjusted groups regardless of PSM adjustment. Endovascular surgery of BBAs exhibits overall more favorable short-term outcome regardless of PSM matching. Microsurgery does not cause a higher fatality rate, hence it could be considered a salvage plan for those high-grade BBA patients.


Asunto(s)
Aneurisma Roto , Procedimientos Endovasculares , Aneurisma Intracraneal , Humanos , Microcirugia/efectos adversos , Aneurisma Intracraneal/cirugía , Aneurisma Intracraneal/etiología , Estudios Retrospectivos , Arteria Carótida Interna/cirugía , Puntaje de Propensión , Aneurisma Roto/cirugía , Aneurisma Roto/etiología , Resultado del Tratamiento
13.
J Am Chem Soc ; 143(15): 5826-5835, 2021 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-33848163

RESUMEN

Parastichy, the spiral arrangement of plant organs, is an example of the long-range apparent order seen in biological systems. These ordered arrangements provide scientists with both an aesthetic challenge and a mathematical inspiration. Synthetic efforts to replicate the regularity of parastichy may allow for molecular-scale control over particle arrangement processes. Here we report the packing of a supramolecular truncated cuboctahedron (TCO) into double-helical (DH) nanowires on a graphite surface with a non-natural parastichy pattern ascribed to the symmetry of the TCOs and interactions between TCOs. Such a study is expected to advance our understanding of the design inputs needed to create complex, but precisely controlled, hierarchical materials. It is also one of the few reported helical packing structures based on Platonic or Archimedean solids since the discovery of the Boerdijk-Coxeter helix. As such, it may provide experimental support for studies of packing theory at the molecular level.


Asunto(s)
Sustancias Macromoleculares/química , Nanocables/química , Grafito/química , Microscopía Electrónica de Transmisión , Conformación Molecular , Método de Montecarlo , Platino (Metal)/química , Porfirinas/química
14.
Plant Biotechnol J ; 19(5): 1052-1064, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33368943

RESUMEN

Nucleotide-binding site-leucine-rich repeat (NB-LRR) resistance proteins are critical for plant resistance to pathogens; however, their mechanism of activation and signal transduction is still not well understood. We identified a mutation in an as yet uncharacterized rice coiled-coil (CC)-NB-LRR, Oryza sativa RPM1-like resistance gene 1 (OsRLR1), which leads to hypersensitive response (HR)-like lesions on the leaf blade and broad-range resistance to the fungal pathogen Pyricularia oryzae (syn. Magnaporthe oryzae) and the bacterial pathogen Xanthomonas oryzae pv. oryzae, together with strong growth reduction. Consistently, OsRLR1-overexpression lines showed enhanced resistance to both pathogens. Moreover, we found that OsRLR1 mediates the defence response through direct interaction in the nucleus with the transcription factor OsWRKY19. Down-regulation of OsWRKY19 in the rlr1 mutant compromised the HR-like phenotype and resistance response, and largely restored plant growth. OsWRKY19 binds to the promoter of OsPR10 to activate the defence response. Taken together, our data highlight the role of a new residue involved in the NB-LRR activation mechanism, allowing identification of a new NB-LRR downstream signalling pathway.


Asunto(s)
Oryza , Xanthomonas , Ascomicetos , Sitios de Unión , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Nucleótidos , Oryza/genética , Oryza/metabolismo , Enfermedades de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
15.
Breed Sci ; 71(5): 510-519, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35087315

RESUMEN

In the absence of pathogen attack, lesion mimic mutants (LMMs) in plants undergo spontaneous cell death and develop necrosis or apoptosis-like lesions on the leaves or sheath, resembling symptoms of hypersensitive response. In-depth research has been conducted on LMMs, especially regarding the molecular mechanisms underlying programmed cell death and disease resistance. In this study, the spotted leaf 36 (spl36) mutant was identified as a typical LMM, showing lesions on both the leaf blade and leaf sheath. The formation of lesions was found to be caused by cell death accompanied by accumulation of hydrogen peroxide and degradation of chloroplasts. Compared with wild-type, the main agronomic traits such as plant height, effective panicle number, panicle length, grain per panicle, seed setting rate, and 1000-grain weight of spl36 were significantly reduced. The defence and pathogenesis-related genes PR1a, PR1b, PR10, and NPR1, were transcriptionally activated in mutant spl36 without pathogen attack. Genetic analysis showed that the mutant phenotype was controlled by the gene SPL36, which was mapped to an interval of 260 kb at the end of the long arm on chromosome 11. Pathogen inoculation analysis showed that spl36 has enhanced resistance to sheath blight, rice blast, and bacterial blight.

16.
Molecules ; 26(3)2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-33573149

RESUMEN

The precise operation of molecular motion for constructing complicated mechanically interlocked molecules has received considerable attention and is still an energetic field of supramolecular chemistry. Herein, we reported the construction of two tris[2]pseudorotaxanes metallacycles with acid-base controllable molecular motion through self-sorting strategy and host-guest interaction. Firstly, two hexagonal Pt(II) metallacycles M1 and M2 decorated with different host-guest recognition sites have been constructed via coordination-driven self-assembly strategy. The binding of metallacycles M1 and M2 with dibenzo-24-crown-8 (DB24C8) to form tris[2]pseudorotaxanes complexes TPRM1 and TPRM2 have been investigated. Furthermore, by taking advantage of the strong binding affinity between the protonated metallacycle M2 and DB24C8, the addition of trifluoroacetic acid (TFA) as a stimulus successfully induces an acid-activated motion switching of DB24C8 between the discrete metallacycles M1 and M2. This research not only affords a highly efficient way to construct stimuli-responsive smart supramolecular systems but also offers prospects for precisely control multicomponent cooperative motion.


Asunto(s)
Compuestos Organoplatinos/química , Platino (Metal)/química , Rotaxanos/química , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Éteres Corona/química , Estructura Molecular , Compuestos Organoplatinos/síntesis química , Polímeros/síntesis química , Polímeros/química , Rotaxanos/síntesis química , Ácido Trifluoroacético/química
17.
Plant Cell Physiol ; 61(4): 761-774, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31904850

RESUMEN

Autopolyploids often show growth advantages over their diploid progenitors because of their increased photosynthetic activity; however, the underlying molecular basis of such mechanism remains elusive. In this study, we aimed to characterize autotetraploid pak choi (Brassica rapa ssp. chinensis) at the physiological, cellular and molecular levels. Autotetraploid pak choi has thicker leaves than its diploid counterparts, with relatively larger intercellular spaces and cell size and greater grana thylakoid height. Photosynthetic data showed that the relative electron transport rate (rETR) was markedly higher in autotetraploid than in diploid pak choi. Transcriptomic data revealed that the expressions of genes involved in 'photosynthesis' biological process and 'thylakoids' cellular component were mainly regulated in autotetraploids. Overall, our findings suggested that the increased rETR in the thylakoids contributed to the increased photosynthetic capacity of autotetraploid leaves. Furthermore, we found that the enhanced rETR is associated with increased BrPetC expression, which is likely altered by histone modification. The ectopic expression of BrPetC in Arabidopsis thaliana led to increased rETR and biomass, which were decreased in BrPetC-silenced pak choi. Autotetraploid pak choi also shows altered hormone levels, which was likely responsible for the increased drought resistance and the impaired powdery mildew resistance of this lineage. Our findings further our understanding on how autotetraploidy provides growth advantages to plants.


Asunto(s)
Brassica rapa/genética , Fotosíntesis/genética , Tetraploidía , Arabidopsis/genética , Arabidopsis/metabolismo , Brassica rapa/metabolismo , Transporte de Electrón , Epigénesis Genética , Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Reguladores del Crecimiento de las Plantas/metabolismo , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , ARN de Planta/genética , ARN de Planta/metabolismo , Transcriptoma/genética
18.
New Phytol ; 225(4): 1746-1761, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31621924

RESUMEN

Autophagy is an evolutionarily conserved degradation pathway in the cytoplasm and has emerged as a key defense mechanism against invading pathogens. However, there is no evidence showing nuclear autophagy in plants. Here, we show that a geminivirus nuclear protein, C1 of tomato leaf curl Yunnan virus (TLCYnV) induces autophagy and interacts directly with the core autophagy-related protein ATG8h. The interaction between ATG8h and C1 leads to the translocation of the C1 protein from the nucleus to the cytoplasm and the decreased protein accumulation of C1, which is dependent on the exportin1-mediated nuclear export pathway. The degradation of C1 is blocked by autophagy inhibitors and compromised when the autophagy-related genes (ATGs) ATG8h, ATG5, or ATG7 are knocked down. Similarly, silencing of these ATGs also promotes TLCYnV infection in Nicotiana benthamiana and Solanum lycopersicum plants. The mutation of a potential ATG8 interacting motif (AIM) in C1 abolishes its interaction with ATG8h in the cytoplasm but favors its interaction with Fibrillarin1 in the nucleolus. TLCYnV carrying the AIM mutation displays enhanced pathogenicity in solanaceous plants. Taken together, these data suggest that a new type of nuclear autophagy-mediated degradation of viral proteins through an exportin1-dependent nuclear export pathway restricts virus infection in plants.


Asunto(s)
Autofagia/fisiología , Geminiviridae/metabolismo , Nicotiana/virología , Proteínas de la Nucleocápside/metabolismo , Enfermedades de las Plantas/virología , Solanum lycopersicum/virología , Regulación de la Expresión Génica de las Plantas/inmunología , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
19.
New Phytol ; 228(2): 622-639, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32479643

RESUMEN

Autophagy is an evolutionarily conserved pathway in eukaryotes that delivers unwanted cytoplasmic materials to the lysosome/vacuole for degradation/recycling. Stimulated autophagy emerges as an integral part of plant immunity against intracellular pathogens. In this study, we used turnip mosaic virus (TuMV) as a model to investigate the involvement of autophagy in plant RNA virus infection. The small integral membrane protein 6K2 of TuMV, known as a marker of the virus replication site and an elicitor of the unfolded protein response (UPR), upregulates the selective autophagy receptor gene NBR1 in a UPR-dependent manner. NBR1 interacts with TuMV NIb, the RNA-dependent RNA polymerase of the virus replication complex (VRC), and the autophagy cargo receptor/adaptor protein ATG8f. The NIb/NBR1/ATG8f interaction complexes colocalise with the 6K2-stained VRC. Overexpression of NBR1 or ATG8f enhances TuMV replication, and deficiency of NBR1 or ATG8f inhibits virus infection. In addition, ATG8f interacts with the tonoplast-specific protein TIP1 and the NBR1/ATG8f-containing VRC is enclosed by the TIP1-labelled tonoplast. In TuMV-infected cells, numerous membrane-bound viral particles are evident in the vacuole. Altogether these results suggest that TuMV activates and manipulates UPR-dependent NBR1-ATG8f autophagy to target the VRC to the tonoplast to promote viral replication and virion accumulation.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Potyvirus , Virosis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Autofagia , Proteínas Portadoras , Enfermedades de las Plantas , ARN de Planta , Respuesta de Proteína Desplegada , Proteínas Virales/metabolismo
20.
Proc Natl Acad Sci U S A ; 114(37): 9984-9989, 2017 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-28847935

RESUMEN

The spikelet is a unique inflorescence structure in grass. The molecular mechanisms behind the development and evolution of the spikelet are far from clear. In this study, a dominant rice mutant, lateral florets 1 (lf1), was characterized. In the lf1 spikelet, lateral floral meristems were promoted unexpectedly and could generally blossom into relatively normal florets. LF1 encoded a class III homeodomain-leucine zipper (HD-ZIP III) protein, and the site of mutation in lf1 was located in a putative miRNA165/166 target sequence. Ectopic expression of both LF1 and the meristem maintenance gene OSH1 was detected in the axil of the sterile lemma primordia of the lf1 spikelet. Furthermore, the promoter of OSH1 could be bound directly by LF1 protein. Collectively, these results indicate that the mutation of LF1 induces ectopic expression of OSH1, which results in the initiation of lateral meristems to generate lateral florets in the axil of the sterile lemma. This study thus offers strong evidence in support of the "three-florets spikelet" hypothesis in rice.


Asunto(s)
Inflorescencia/genética , Inflorescencia/fisiología , Oryza/crecimiento & desarrollo , Oryza/genética , Flores/genética , Regulación de la Expresión Génica de las Plantas/genética , Genes de Plantas , Inflorescencia/crecimiento & desarrollo , Inflorescencia/metabolismo , Meristema/genética , Meristema/fisiología , Mutación , Proteínas de Plantas/genética , Poaceae/genética
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