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1.
Front Oncol ; 14: 1335009, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38651156

RESUMO

Background: Based on pharmacoeconomics, drug availability and actual treatment, optimal treatment regimens for Chinese non-small-cell lung carcinoma (NSCLC) patients over 70 years old are needed. Methods: This multicenter, single-arm pilot trial enrolled patients with advanced non-squamous NSCLC who refused systemic chemotherapy. Eligible patients received anlotinib (12 mg/day, d1-14, Q3W) until disease progression, intolerant toxicities, or withdrawal from the study. The primary endpoint was progression-free survival (PFS). Results: Forty-nine patients were screened between January 2019 and September 2021, of whom 40 patients were eligible. The median age was 76 years. With a median follow-up period of 16.20 (95% CI: 8.77, 25.10) months, the median PFS was 5.45 months (95% CI: 3.52-9.23) and the median overall survival was 10.32 months (95% CI: 6.44-12.78). Three patients achieved a partial response and 34 had stable disease, with an objective response rate of 7.5% and a disease control rate of 92.5%. Thirty-three (82.5%; 33/40) patients reported treatment-related adverse events (TRAEs) of any grade, and the incidence rate of grade ≥3 TRAEs was 35% (14/40). The most common grade ≥3 TRAEs were hypertension (4/40; 10.0%), hand-foot syndrome (3/40; 7.5%), and proteinuria (2/40; 5.0%). Conclusion: Anlotinib treatment was feasible and safe in Chinese elderly patients with advanced non-squamous NSCLC who did not receive any systemic chemotherapy.

2.
Nat Commun ; 15(1): 2894, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570494

RESUMO

Steroidal glycoalkaloids (SGAs) are major plant defense metabolites against pests, while they are considered poisonous in food. The genetic basis that guides negative selection of SGAs production during tomato domestication remains poorly understood. Here, we identify a distal enhancer, GAME Enhancer 1 (GE1), as the key regulator of SGAs metabolism in tomato. GE1 recruits MYC2-GAME9 transcriptional complex to regulate the expression of GAME cluster genes via the formation of chromatin loops located in the neighboring DNA region. A naturally occurring GE176 allelic variant is found to be more active in stimulating GAME expression. We show that the weaker GE1 allele has been the main driver for selecting reduced SGAs levels during tomato domestication. Unravelling the "TFs-Enhancer-Promoter" regulatory mechanism operating in SGAs metabolism opens unprecedented prospects for SGAs manipulation in Solanaceae via precision breeding strategies.


Assuntos
Solanaceae , Solanum lycopersicum , Solanum lycopersicum/genética , Domesticação , Melhoramento Vegetal , Esteroides
3.
Artigo em Inglês | MEDLINE | ID: mdl-38656839

RESUMO

In this paper, we propose a graph-represented image distribution similarity (GRIDS) index for full-reference (FR) image quality assessment (IQA), which can measure the perceptual distance between distorted and reference images by assessing the disparities between their distribution patterns under a graph-based representation. First, we transform the input image into a graph-based representation, which is proven to be a versatile and effective choice for capturing visual perception features. This is achieved through the automatic generation of a vision graph from the given image content, leading to holistic perceptual associations for irregular image regions. Second, to reflect the perceived image distribution, we decompose the undirected graph into cliques and then calculate the product of the potential functions for the cliques to obtain the joint probability distribution of the undirected graph. Finally, we compare the distances between the graph feature distributions of the distorted and reference images at different stages; thus, we combine the distortion distribution measurements derived from different graph model depths to determine the perceived quality of the distorted images. The empirical results obtained from an extensive array of experiments underscore the competitive nature of our proposed method, which achieves performance on par with that of the state-of-the-art methods, demonstrating its exceptional predictive accuracy and ability to maintain consistent and monotonic behaviour in image quality prediction tasks. The source code is publicly available at the following website1.

4.
Zhongguo Fei Ai Za Zhi ; 27(3): 241-244, 2024 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-38590198

RESUMO

With the continuous innovation of genomics, proteomics and molecular biological detection technology, the treatment of non-small cell lung cancer (NSCLC) has changed from traditional chemotherapy to immunotherapy and targeted therapy. Among them, molecular tumor markers targeting tyrosine kinase pathways play more important roles in clinical practice. For advanced NSCLC patients with positive epidermal growth factor receptor (EGFR) mutations, there are many first-line drugs on the market and they could bring significant efficacy, thus completely subverting the treatment pattern of advanced NSCLC. Common mutations of EGFR in Chinese patients are located on exons 19, 20 and 21, of which exons 19 and 21 mutations are the more common types. Besides, there is also a subtype of EGFR mutations, known as EGFR 20 exon insertion (EGFR 20ins) mutation. The authors summarized the treatment of a lung adenocarcinoma patient with EGFR 20ins mutation accepting Furmonertinib mesylate, in order to provide effective references for clinical diagnosis and treatment.
.


Assuntos
Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Indóis , Neoplasias Pulmonares , Piridinas , Pirimidinas , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Receptores ErbB/genética , Mutação , Éxons
5.
New Phytol ; 242(2): 592-609, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38402567

RESUMO

The plant hormone ethylene plays a critical role in fruit defense against Botrytis cinerea attack, but the underlying mechanisms remain poorly understood. Here, we showed that ethylene response factor SlERF.C1 acts as a key regulator to trigger the ethylene-mediated defense against B. cinerea in tomato fruits without compromising ripening. Knockout of SlERF.C1 increased fruit susceptibility to B. cinerea with no effect on ripening process, while overexpression enhanced resistance. RNA-Seq, transactivation assays, EMSA and ChIP-qPCR results indicated that SlERF.C1 activated the transcription of PR genes by binding to their promoters. Moreover, SlERF.C1 interacted with the mitogen-activated protein kinase SlMPK8 which allowed SlMPK8 to phosphorylate SlERF.C1 at the Ser174 residue and increases its transcriptional activity. Knocking out of SlMPK8 increased fruit susceptibility to B. cinerea, whereas overexpression enhanced resistance without affecting ripening. Furthermore, genetic crosses between SlMPK8-KO and SlERF.C1-OE lines reduced the resistance to B. cinerea attack in SlERF.C1-OE fruits. In addition, B. cinerea infection induced ethylene production which in turn triggered SlMPK8 transcription and enhanced the phosphorylation of SlERF.C1. Overall, our findings reveal the regulatory mechanism of the 'Ethylene-MPK8-ERF.C1-PR' module in resistance against B. cinerea and provide new insight into the manipulation of gray mold disease in fruits.


Assuntos
Frutas , Solanum lycopersicum , Frutas/metabolismo , Solanum lycopersicum/genética , Etilenos/metabolismo , Botrytis/fisiologia , Doenças das Plantas/genética , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas
6.
Hortic Res ; 11(1): uhad238, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38222823

RESUMO

As two of the most abundant post-translational modifications, phosphorylation and ubiquitination play a significant role in modulating plant-pathogen interactions and increasing evidence indicates their crosstalk in plant immunity. Rose (Rosa sp.) is one of the most important ornamental plants and can be seriously infected by Botrytis cinerea. Here, integrated proteomics analysis was performed to detect global proteome, phosphorylation, and ubiquitination changes in rose upon B. cinerea infection and investigate the possible phosphorylation and ubiquitination crosstalk. A total of 6165 proteins, 11 774 phosphorylation and 10 582 ubiquitination sites, and 77 phosphorylation and 13 ubiquitination motifs were identified. Botrytis cinerea infection resulted in 169 up-regulated and 122 down-regulated proteins, 291 up-regulated and 404 down-regulated phosphorylation sites, and 250 up-regulated and 634 down-regulated ubiquitination sites. There were 12 up-regulated PR10 proteins and half of them also showed reduced ubiquitination. A lot of kinases probably involved in plant pattern-triggered immunity signaling were up-regulated phosphoproteins. Noticeably, numerous kinases and ubiquitination-related proteins also showed a significant change in ubiquitination and phosphorylation, respectively. A cross-comparison of phosphoproteome and ubiquitylome indicated that both of two post-translational modifications of 104 proteins were dynamically regulated, and many putative pattern-triggered immunity signaling components in the plant plasma membrane were co-regulated. Moreover, five selected proteins, including four PR10 proteins and a plasma membrane aquaporin, were proven to be involved in rose resistance to B. cinerea. Our study provides insights into the molecular mechanisms underlying rose resistance to B. cinerea and also increases the database of phosphorylation and ubiquitination sites in plants.

7.
New Phytol ; 241(6): 2540-2557, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38263687

RESUMO

Some essential components of fleshy fruits are dependent on photosynthetic activity and carbohydrate metabolism. Nevertheless, the regulatory mechanisms linking chlorophyll and carbohydrate metabolism remain partially understood. Here, we uncovered the role of SlGRAS9 and SlZHD17 transcription factors in controlling chlorophyll and carbohydrate accumulation in tomato fruit. Knockout or knockdown of SlGRAS9 or SlZHD17 resulted in marked increase in chlorophyll content, reprogrammed chloroplast biogenesis and enhanced accumulation of starch and soluble sugars. Combined genome-wide transcriptomic profiling and promoter-binding experiments unveiled a complex mechanism in which the SlGRAS9/SlZHD17 regulatory module modulates the expression of chloroplast and sugar metabolism either via a sequential transcriptional cascade or through binding of both TFs to the same gene promoters, or, alternatively, via parallel pathways where each of the TFs act on different target genes. For instance, the regulation of SlAGPaseS1 and SlSUS1 is mediated by SlZHD17 whereas that of SlVI and SlGLK1 occurs only through SlGRAS9 without the intervention of SlZHD17. Both SlGRAS9 and SlZHD17 can also directly bind the promoter of SlPOR-B to regulate its expression. Taken together, our findings uncover two important regulators acting synergistically to manipulate chlorophyll and carbohydrate accumulation and provide new potential breeding targets for improving fruit quality in fleshy fruits.


Assuntos
Clorofila , Solanum lycopersicum , Clorofila/metabolismo , Solanum lycopersicum/genética , Frutas/fisiologia , Melhoramento Vegetal , Metabolismo dos Carboidratos/genética , Carboidratos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
8.
New Phytol ; 241(3): 1177-1192, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37985404

RESUMO

The locular gel, produced by the placenta, is important for fruit flavor and seed development in tomato. However, the mechanism underlying locule and placenta development is not fully understood yet. Here, we show that two SlARF transcription factors, SlARF8B and SlARF8A (SlARF8A/B), promote the development of locular and placenta tissues. The expression of both SlARF8A and SlARF8B is repressed by sly-microRNA167 (sly-miR167), allowing for the activation of auxin downstream genes. In slarf8a, slarf8b, and slarf8a/b mutants, the auxin (IAA) levels are decreased, whereas the levels of inactive IAA conjugates including IAA-Ala, IAA-Asp, and IAA-Glu are increased. We further find that SlARF8B directly inhibits the expression of SlGH3.4, an acyl acid amino synthetase that conjugates the amino acids to IAA. Disruption of such auxin balance by the increased expression of SlGH3.4 or SlGH3.2 results in defective locular and placental tissues. Taken together, our findings reveal an important regulatory module constituted by sly-miR167-SlARF8A/B-SlGH3.4 during the development of locular and placenta tissues of tomato fruits.


Assuntos
Frutas , Solanum lycopersicum , Gravidez , Feminino , Humanos , Solanum lycopersicum/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Retroalimentação , Placenta/metabolismo , Ácidos Indolacéticos/metabolismo , Homeostase , Regulação da Expressão Gênica de Plantas
9.
Plant Biotechnol J ; 22(2): 413-426, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37816143

RESUMO

Chilling injury has a negative impact on the quantity and quality of crops, especially subtropical and tropical plants. The plant cell wall is not only the main source of biomass production, but also the first barrier to various stresses. Therefore, improving the understanding of the alterations in cell wall architecture is of great significance for both biomass production and stress adaptation. Herein, we demonstrated that the cell wall principal component cellulose accumulated during chilling stress, which was caused by the activation of MaCESA proteins. The sequence-multiple comparisons show that a cold-inducible NAC transcriptional factor MaNAC1, a homologue of Secondary Wall NAC transcription factors, has high sequence similarity with Arabidopsis SND3. An increase in cell wall thickness and cellulosic glucan content was observed in MaNAC1-overexpressing Arabidopsis lines, indicating that MaNAC1 participates in cellulose biosynthesis. Over-expression of MaNAC1 in Arabidopsis mutant snd3 restored the defective secondary growth of thinner cell walls and increased cellulosic glucan content. Furthermore, the activation of MaCESA7 and MaCESA6B cellulose biosynthesis genes can be directly induced by MaNAC1 through binding to SNBE motifs within their promoters, leading to enhanced cellulose content during low-temperature stress. Ultimately, tomato fruit showed greater cold resistance in MaNAC1 overexpression lines with thickened cell walls and increased cellulosic glucan content. Our findings revealed that MaNAC1 performs a vital role as a positive modulator in modulating cell wall cellulose metabolism within banana fruit under chilling stress.


Assuntos
Arabidopsis , Musa , Celulose/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Musa/genética , Musa/metabolismo , Frutas/genética , Frutas/metabolismo , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas/genética
11.
Food Res Int ; 173(Pt 1): 113316, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803628

RESUMO

Inappropriate low temperature storage usually leads to quality deterioration of harvested tomato fruits. In this study, we performed comparative metabolome, transcriptome, and proteome analyses to comprehensively understand the effects of low temperature on metabolic changes in tomato fruit (fresh fruit, C0d; 4 °C 8 days, C8d; 4 °C 7 days and then 25 °C 1 day, C7dS1). Large amounts of secondary metabolites (including flavonoids and phenolic acids) increased after low temperature treatment. The overlap differentially accumulated metabolites in three comparative groups (C0d vs. C8d, C0d vs. C7dS1, C8d vs. C7dS1) were mainly flavonoid metabolites. A total of 1438 differentially expressed genes identified in these three comparative groups were primarily enriched in metabolic pathways and secondary metabolites biosynthesis pathways. Similarly, proteomic analysis showed that the differentially expressed proteins were enriched in the secondary metabolites biosynthesis and phenylpropanoid biosynthesis pathways. There was a strong correlation between changes in flavonoid metabolites and the expression of chalcone synthase (SlCHS), chalcone isomerase-like (SlCHIL), and coumarate 3-hydroxylase (SlC3H), which are involved in the phenylpropanoid and flavonoid biosynthesis. Additionally, seven differentially expressed MYB transcription factors were identified; SlMYB91, SlMYB106, and SlMYB70 strongly correlated with flavonoid biosynthesis structural genes after low temperature treatment. Other genes involved in fruit ripening and quality were also affected by low temperature. The data generated in this study may unravel the transcriptional regulatory network of secondary metabolism associated with low-temperature storage and provide a solid foundation for future studies.


Assuntos
Frutas , Solanum lycopersicum , Frutas/genética , Frutas/metabolismo , Solanum lycopersicum/genética , Proteômica , Metabolismo Secundário , Multiômica , Temperatura , Flavonoides/metabolismo
12.
BMC Plant Biol ; 23(1): 495, 2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37833639

RESUMO

The SHI RELATED SEQUENCE (SRS) family plays a vital role in the development of multiple plant organs such as floral meristem determinacy, organ morphogenesis, and signal transduction. Nevertheless, there is little understanding of the biological significance of tomato SRS family at this point. Our research identified eight SlSRS family members and classified them into three subfamilies based on phylogenetics, conserved motifs, and characteristic domain analysis. The intraspecies and interspecies collinearity analysis revealed clues of SRS family evolution. Many cis-elements related to hormones, stresses, and plant development can be found in the promoter region of SlSRS genes. All of eight SlSRS proteins were located in the nucleus and possessed transcriptional activity, half of which were transcriptional activators, and the other half were transcriptional repressors. Except for SlSRS1, which showed high transcript accumulation in vegetative organs, most SlSRS genes expressed ubiquitously in all flower organs. In addition, all SlSRS genes could significantly respond to at least four different plant hormones. Further, expression of SlSRS genes were regulated by various abiotic stress conditions. In summary, we systematically analyzed and characterized the SlSRS family, reviewed the expression patterns and preliminarily investigated the protein function, and provided essential information for further functional research of the tomato SRS genes in the determination of reproductive floral organs and the development of plants, and possibly other plants.


Assuntos
Solanum lycopersicum , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Solanum lycopersicum/genética , Regulação da Expressão Gênica de Plantas , Família Multigênica , Hormônios , Estresse Fisiológico/genética , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
13.
Heliyon ; 9(9): e19910, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37810088

RESUMO

Giant landslides and dammed lakes occurred frequently during the prehistoric period; however, their mechanisms often remain an open issue because they are complex. This study used field investigations to observe four old landslides and three landslide dams in Daning County, Shanxi Province, China. Remote sensing images captured during different periods were used to compare the landforms of landslides, landslide dams, and their surrounding environments in detail. Subsequently, their shapes, scales, spatial distributions, and positional relationships were determined. The ages of 14C obtained from the paleolandslide dam lake (PDL) deposits were 3742 ± 95, 4115 ± 121, 6544 ± 91, 7814 ± 109 cal a BP. The 14C ages of the deposits under the sliding surfaces of the old landslides were 2748 ± 27, 4470 ± 54, and 8245 ± 79 cal a BP. Based on the actual physical geographical conditions and geomorphological characteristics of the region, combined with the above age data, that the following conclusions were made: (i) During the Holocene, from 2700 to 8200 years ago, heavy rainfall was the main reason for the occurrence of landslides and landslide dams in the region. (ii) Under the condition of heavy rainfall, the slopes with angles >60° in the Loess Plateau are prone to form landslide masses, and the size of the landslide is related to rainfall intensity. A landslide dam was easily formed when the sliding direction was perpendicular to the direction of the valley. It is difficult to form landslide dams when the sliding direction is almost consistent with the downward direction of the valley. (iii) The formation mechanism of old landslides shows that collapse or sliding may occur suddenly in loess geological masses under an external rainfall scenario. Moreover, the process of landslide dams is related to the geomorphic forms of the original valley.

14.
Pest Manag Sci ; 79(12): 5073-5086, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37572366

RESUMO

BACKGROUND: As a highly prevalent epidemic disease of potato, late blight caused by Phytophthora infestans poses a serious threat to potato yield and quality. At present, chemical fungicides are mainly used to control potato late blight, but long-term overuse of chemical fungicides may lead to environmental pollution and human health threats. Endophytes, natural resources for plant diseases control, can promote plant growth, enhance plant resistance, and secrete antifungal substances. Therefore, there is an urgent need to find some beneficial endophytes to control potato late blight. RESULTS: We isolated a strain of Bacillus subtilis H17-16 from potato healthy roots. It can significantly inhibit mycelial growth, sporangia germination and the pathogenicity of Phytophthora infestans, induce the resistance of potato to late blight, and promote potato growth. In addition, H17-16 has the ability to produce protease, volatile compounds (VOCs) and form biofilms. After H17-16 treatment, most of the genes involved in metabolism, virulence and drug resistance of Phytophthora infestans were down-regulated significantly, and the genes related to ribosome biogenesis were mainly up-regulated. Moreover, field and postharvest application of H17-16 can effectively reduce the occurrence of potato late blight, and the combination of H17-16 with chitosan or chemical fungicides had a better effect than single H17-16. CONCLUSION: Our results reveal that Bacillus subtilis H17-16 has great potential as a natural fungicide for controlling potato late blight, laying a theoretical basis for its development as a biological control agent. © 2023 Society of Chemical Industry.


Assuntos
Fungicidas Industriais , Phytophthora infestans , Solanum tuberosum , Humanos , Phytophthora infestans/genética , Solanum tuberosum/genética , Bacillus subtilis , Fungicidas Industriais/farmacologia , Raízes de Plantas , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
15.
Plant Sci ; 335: 111790, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37454820

RESUMO

Leaf is the main photosynthetic organ in plants and the primary energy source all along the plant life. Given the beneficial role of leaf rolling in improving photosynthetic efficiency and yield in specific environmental conditions, a better understanding of the factors and molecular mechanisms underlying this process is highly suited. Previously, the SlARF4 knocking out mutant exhibited upward curly leaf showed higher resistance to water deficit which driving us to uncover the function of SlARF4 in regulating the curly leaf formation. In this study, we unraveled the unexplored role of the SlARF4-SlHB8 module of transcription factors in the development of leaf rolling. Both SlARF4 loss-of-function and SlHB8 overexpressing tomato plants exhibited upward-rolled leaves, reflecting the active role of the two genes in controlling leaf rolling. Dual-luciferase reporter assays and phenotypic analysis of hybrid progenies suggested that SlHB8 acts downstream of SlARF4 in curly leaf formation. SlARF4 and SlHB8 influence the development of leaf palisade tissues via modulating the expression of genes associated with curly leaf formation. SEM analysis revealed no significant differences in leaf epidermal cells between the two leaf-rolling mutants and the wild type, indicating that curly leaves of arf4 and SlHB8-OE do not result from the asymmetric leaf epidermal cell growth. Our data provide novel insight into the molecular mechanism of abaxial-adaxial determination involving SlARF4 and SlHB8 and reveals that leaf rolling operates via different regulation mechanisms in tomato and Arabidopsis model plant.


Assuntos
Arabidopsis , Solanum lycopersicum , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Solanum lycopersicum/genética , Fenótipo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Folhas de Planta/metabolismo , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas
16.
New Phytol ; 239(3): 949-963, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37247338

RESUMO

Ascorbic acid (AsA) is a water-soluble antioxidant that plays important roles in plant development and human health. Understanding the regulatory mechanism underlying AsA biosynthesis is imperative to the development of high AsA plants. In this study, we reveal that the auxin response factor SlARF4 transcriptionally inhibits SlMYB99, which subsequently modulates AsA accumulation via transcriptional activation of AsA biosynthesis genes GPP, GLDH, and DHAR. The auxin-dependent transcriptional cascade of SlARF4-SlMYB99-GPP/GLDH/DHAR modulates AsA synthesis, while mitogen-activated protein kinase SlMAPK8 not only phosphorylates SlMYB99, but also activates its transcriptional activity. Both SlMYB99 and SlMYB11 proteins physically interact with each other, thereby synergistically regulating AsA biosynthesis by upregulating the expression of GPP, GLDH, and DHAR genes. Collectively, these results demonstrate that auxin and abscisic acid antagonistically regulate AsA biosynthesis during development and drought tolerance in tomato via the SlMAPK8-SlARF4-SlMYB99/11 module. These findings provide new insights into the mechanism underlying phytohormone regulation of AsA biosynthesis and provide a theoretical basis for the future development of high AsA plants via molecular breeding.


Assuntos
Ácido Abscísico , Solanum lycopersicum , Humanos , Solanum lycopersicum/genética , Ácidos Indolacéticos , Ácido Ascórbico , Antioxidantes/metabolismo , Regulação da Expressão Gênica de Plantas
17.
Hortic Res ; 10(3): uhac286, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36938568

RESUMO

The formation and development of pollen are among the most critical processes for reproduction and genetic diversity in the life cycle of flowering plants. The present study found that SlMYB72 was highly expressed in the pollen and tapetum of tomato flowers. Downregulation of SlMYB72 led to a decrease in the amounts of seeds due to abnormal pollen development compared with wild-type plants. Downregulation of SlMYB72 delayed tapetum degradation and inhibited autophagy in tomato anther. Overexpression of SlMYB72 led to abnormal pollen development and delayed tapetum degradation. Expression levels of some autophagy-related genes (ATGs) were decreased in SlMYB72 downregulated plants and increased in overexpression plants. SlMYB72 was directly bound to ACCAAC/ACCAAA motif of the SlATG7 promoter and activated its expression. Downregulation of SlATG7 inhibited the autophagy process and tapetum degradation, resulting in abnormal pollen development in tomatoes. These results indicated SlMYB72 affects the tapetum degradation and pollen development by transcriptional activation of SlATG7 and autophagy in tomato anther. The study expands the understanding of the regulation of autophagy by SlMYB72, uncovers the critical role that autophagy plays in pollen development, and provides potential candidate genes for the production of male-sterility in plants.

18.
Metab Eng ; 77: 41-52, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36893914

RESUMO

Sesquiterpenes represent a large class of terpene compounds found in plants with broad applications such as pharmaceuticals and biofuels. The plastidial MEP pathway in ripening tomato fruit is naturally optimized to provide the 5-carbon isoprene building blocks of all terpenes for production of the tetraterpene pigment lycopene and other carotenoids, making it an excellent plant system to be engineered for production of high-value terpenoids. We reconstituted and enhanced the pool of sesquiterpene precursor farnesyl diphosphate (FPP) in plastids of tomato fruit by overexpressing the fusion gene DXS-FPPS encoding a fusion protein of 1-deoxy-D-xylulose 5-phosphate synthase (DXS) linked with farnesyl diphosphate synthase (originally called farnesyl pyrophosphate synthase, and abbreviated as FPPS) under the control of fruit-ripening specific polygalacturonase (PG) promoter concomitant with substantial reduction in lycopene content and large production of FPP-derived squalene. The supply of precursors achieved by the fusion gene expression can be harnessed by an engineered sesquiterpene synthase that is retargeted to plastid to engineer high-yield sesquiterpene production in tomato fruit, offering an effective production system for high-value sesquiterpene ingredients.


Assuntos
Sesquiterpenos , Solanum lycopersicum , Solanum lycopersicum/genética , Licopeno/metabolismo , Frutas/genética , Frutas/metabolismo , Sesquiterpenos/metabolismo , Terpenos/metabolismo , Geraniltranstransferase/genética , Geraniltranstransferase/metabolismo , Plastídeos/genética , Plastídeos/metabolismo
19.
Plant Sci ; 330: 111642, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36804389

RESUMO

As signal molecules, plant peptides play key roles in intercellular communication during growth and development, as well as stress responses. The 14-amino-acid (aa) INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) peptide was originally identified to play an essential role in the floral organ abscission of Arabidopsis. It is synthesized from its precursor, a small protein containing 77-aa residues with an N-terminal signal peptide sequence. Recently, the IDA/IDA-like (IDLs) genes are isolated in several angiosperms and are highly conserved in land plants. In addition, IDA/IDLs are not only involved in organ abscission but also function in multiple biological processes, including biotic and abiotic stress responses. Here, we summarize the post-translational modification and proteolytic processing, the evolutionary conservation, and the potential regulatory function of IDA/IDLs, and also present future perspectives to investigate the IDA/IDLs signaling pathway. We anticipate that this detailed knowledge will help to improve the understanding of the molecular mechanism of plant peptide signaling.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Flores/genética , Transdução de Sinais , Arabidopsis/metabolismo , Plantas/genética , Plantas/metabolismo , Peptídeos/metabolismo , Regulação da Expressão Gênica de Plantas
20.
Food Chem ; 408: 135181, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36525727

RESUMO

Anthocyanins are natural pigments with diverse physiological roles and protective effects, but most tomatoes produce little. In this study, the anthocyanin characteristics, nutritional properties, and postharvest attributes of purple tomato (SlMYB75-OE) obtained by overexpression of SlMYB75 gene were first analyzed. Compared to wild-type (WT), eight monomeric anthocyanins were newly produced by overexpression of SlMYB75, and further study demonstrated the expression of dihydroflavonol-4-reductase (SlDFR) and two UDP-glycosyltransferase (SlUGTs) genes was activated by SlMYB75. The contents of sugars (sucrose, glucose, and fructose) and citric acid content in SlMYB75-OE were higher and lower, respectively, than in WT. In addition, FRAP and DPPH assays indicated SlMYB75-OE had higher antioxidant capacity, when compared to WT. Moreover, SlMYB75-OE exhibited a longer shelf life and stronger resistance to Botrytis cinerea than WT, and this characteristic was positively correlated with anthocyanin content. These results help to clarify the function of SlMYB75 and provide a reference for tomato breeding.


Assuntos
Antocianinas , Solanum lycopersicum , Antocianinas/metabolismo , Solanum lycopersicum/genética , Melhoramento Vegetal , Antioxidantes/metabolismo , Glucose , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
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