RESUMO
Photoperiod is a crucial environmental cue for phenological responses, including growth cessation and winter dormancy in perennial woody plants. Two regulatory modules within the photoperiod pathway explain bud dormancy induction in poplar (Populus spp.): the circadian oscillator LATE ELONGATED HYPOCOTYL 2 (LHY2) and GIGANTEA-like genes (GIs) both regulate the key target for winter dormancy induction FLOWERING LOCUS T2 (FT2). However, modification of LHY2 and GIs cannot completely prevent growth cessation and bud set under short-day (SD) conditions, indicating that additional regulatory modules are likely involved. We identified PtoHY5a, an orthologs of the photomorphogenesis regulatory factor ELONGATED HYPOCOTYL 5 (HY5) in poplar (Populus tomentosa), that directly activates PtoFT2 expression and represses the circadian oscillation of LHY2, indirectly activating PtoFT2 expression. Thus, PtoHY5a suppresses SD-induced growth cessation and bud set. Accordingly, PtoHY5a knockout facilitates dormancy induction. PtoHY5a also inhibits bud-break in poplar by controlling gibberellic acid (GA) levels in apical buds. Additionally, PtoHY5a regulates the photoperiodic control of seasonal growth downstream of phytochrome PHYB2. Thus, PtoHY5a modulates seasonal growth in poplar by regulating the PtoPHYB2-PtoHY5a-PtoFT2 module to determine the onset of winter dormancy, and by fine-tuning GA levels to control bud-break.
Assuntos
Regulação da Expressão Gênica de Plantas , Giberelinas , Fotoperíodo , Dormência de Plantas , Proteínas de Plantas , Populus , Populus/genética , Populus/crescimento & desenvolvimento , Populus/metabolismo , Populus/fisiologia , Giberelinas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Dormência de Plantas/genética , Flores/genética , Flores/fisiologia , Flores/crescimento & desenvolvimentoRESUMO
Ethylene response factors (ERFs) are downstream components of ethylene-signaling pathways known to play critical roles in ethylene-controlled climacteric fruit ripening, yet little is known about the molecular mechanism underlying their mode of action. Here, we demonstrate that SlERF.F12, a member of the ERF.F subfamily containing Ethylene-responsive element-binding factor-associated Amphiphilic Repression (EAR) motifs, negatively regulates the onset of tomato (Solanum lycopersicum) fruit ripening by recruiting the co-repressor TOPLESS 2 (TPL2) and the histone deacetylases (HDAs) HDA1/HDA3 to repress the transcription of ripening-related genes. The SlERF.F12-mediated transcriptional repression of key ripening-related genes 1-AMINO-CYCLOPROPANE-1-CARBOXYLATE SYNTHASE 2 (ACS2), ACS4, POLYGALACTURONASE 2a, and PECTATE LYASE is dependent on the presence of its C-terminal EAR motif. We show that SlERF.F12 interacts with the co-repressor TPL2 via the C-terminal EAR motif and recruits HDAs SlHDA1 and SlHDA3 to form a tripartite complex in vivo that actively represses transcription of ripening genes by decreasing the level of the permissive histone acetylation marks H3K9Ac and H3K27Ac at their promoter regions. These findings provide new insights into the ripening regulatory network and uncover a direct link between repressor ERFs and histone modifiers in modulating the transition to ripening of climacteric fruit.
Assuntos
Solanum lycopersicum , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Etilenos/metabolismo , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
3-Dehydroquinate dehydratase/shikimate dehydrogenase (DQD/SDH) is a key rate-limiting enzyme that catalyzes the synthesis of the shikimate, which is an important metabolic intermediate in plants and animals. However, the function of SlDQD/SDH family genes in tomato (Solanum lycopersicum) fruit metabolites is still unknown. In the present study, we identified a ripening-associated SlDQD/SDH member, SlDQD/SDH2, that plays a key role in shikimate and flavonoid metabolism. Overexpression of this gene resulted in an increased content of shikimate and flavonoids, while knockout of this gene by CRISPR/Cas9 mediated gene editing led to a significantly lower content of shikimate and flavonoids by downregulation of flavonoid biosynthesis-related genes. Moreover, we showed that SlDQD/SDH2 confers resistance against Botrytis cinerea attack in post-harvest tomato fruit. Dual-luciferase reporter and EMSA assays indicated that SlDQD/SDH2 is a direct target of the key ripening regulator SlTAGL1. In general, this study provided a new insight into the biosynthesis of flavonoid and B. cinerea resistance in fruit tomatoes.
Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Frutas/genética , Frutas/metabolismo , Botrytis/metabolismo , Flavonoides/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
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 PlantasRESUMO
Kiwifruit ripening is a complex and highly coordinated process that occurs in conjunction with the formation of fruit edible quality. The significance of epigenetic changes, particularly the impact of N6-methyladenosine (m6A) RNA modification on fruit ripening and quality formation, has been largely overlooked. We monitored m6A levels and gene expression changes in kiwifruit at four different stages using LC-MS/MS, MeRIP, RNA-seq, and validated the function of AcALKBH10 through heterologous transgenic expression in tomato. Notable m6A modifications occurred predominantly at the stop codons and the 3' UTRs and exhibited a gradual reduction in m6A levels during the fruit ripening process. Moreover, these m6A modifications in the aforementioned sites demonstrated a discernible inverse relationship with the levels of mRNA abundance throughout the ripening process, suggesting a repression effect of m6A modification in the modulation of kiwifruit ripening. We further demonstrated that AcALKBH10 rather than AcECT9 predominantly regulates m6A levels in ripening-related genes, thereby exerting the regulatory control over the ripening process and the accumulation of soluble sugars and organic acids, ultimately influencing fruit ripening and quality formation. In conclusion, our findings illuminate the epi-regulatory mechanism involving m6A in kiwifruit ripening, offering a fresh perspective for cultivating high-quality kiwifruit with enhanced nutritional attributes.
Assuntos
Actinidia , Adenosina , Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , RNA Mensageiro , Actinidia/genética , Actinidia/crescimento & desenvolvimento , Frutas/genética , Frutas/crescimento & desenvolvimento , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Metilação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Plantas Geneticamente Modificadas , Genes de PlantasRESUMO
ß-1,3-Glucanases are considered key regulators responsible for the degradation of callose in plants, yet little is known about the role and mode of action of their encoding genes in tomato (Solanum lycopersicum). In the present study, we identified the ß-1,3-glucanase encoding gene ß-1,3-GLUCANASE10 (SlBG10) and revealed its regulation in tomato pollen and fruit development, seed production, and disease resistance by modulating callose deposition. Compared with wild-type (WT) or SlBG10 overexpressing (SlBG10-OE) lines, knockout of SlBG10 caused pollen arrest and failure to set fruit with reduced male rather than female fecundity. Further analyses showed that SlBG10-knockout promoted callose deposition in anther at the tetrad-to-microspore stages, resulting in pollen abortion and male sterility. Moreover, loss-of-function SlBG10 delayed degradation of endosperm cell wall calloses during cellularization and impeded early seed development. We also uncovered that Botrytis cinerea infection induces SlBG10 expression in WT tomato, and the knockout lines showed increased callose accumulation in fruit pericarps, reduced susceptibility to B. cinerea, and enhanced antioxidant capacity to maintain tomato fruit quality. However, the expression of genes encoding cell wall hydrolases decreased in SlBG10-knockout tomatoes and thus led to an increase in pericarp epidermal thickness, enhancement in fruit firmness, reduction of fruit water loss, and extension of tomato shelf life. These findings not only expand our understanding of the involvement of ß-1,3-glucanases as callose regulators in multiple developmental processes and pathogen resistance but also provide additional insight into the manipulation of multiagronomic traits for targeted tomato breeding.
Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Resistência à Doença/genética , Melhoramento Vegetal , Glucanos/metabolismo , Regulação da Expressão Gênica de Plantas , Botrytis/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Frutas/genética , Frutas/metabolismoRESUMO
Cypripedioideae (slipper orchids; Orchidaceae) currently consist of â¼200 herbaceous species with a strikingly disjunctive distribution in tropical and temperate regions of both hemispheres. In this study, an updated phylogeny with representatives from all five cypripedioid genera was presented based on maximum likelihood and Bayesian inference of plastome and low-copy nuclear genes. Phylogenomic analyses indicated that each genus is monophyletic, but some relationships (e.g., those among Cypripedium sects. Acaulia, Arietinum, Bifolia, Flabellinervia, Obtusipetala and Palangshanensia) conflict with those in previous studies based on Sanger data. Cypripedioideae appeared to have arisen in South America and/or the adjacent Qinghai-Tibet Plateau and Hengduan Mountains â¼35 Mya. We inferred multiple dispersal events between East Asia and North America in Cypripedium, and between mainland Southeast Asia and the Malay Archipelago in Paphiopedilum. In the Americas, divergences among four genera (except Cypripedium) occurred around 31-20 Mya, long before the closure of the Isthmus of Panama, indicating the importance of long-distance dispersal. Evolutionary patterns between morphological and plastome character evolution suggested several traits, genome size and NDH genes, which are likely to have contributed to the success of slipper orchids in alpine floras and low-elevation forests. Species diversification rates were notably higher in epiphytic clades of Paphiopedilum than in other, terrestrial cypripedioids, paralleling similar accelerations associated with epiphytism in other groups. This study also suggested that sea-level fluctuations and mountain-building processes promoted the diversification of the largest genera, Paphiopedilum and Cypripedium.
Assuntos
Orchidaceae , Filogenia , Filogeografia , Orchidaceae/genética , Orchidaceae/classificação , Teorema de Bayes , Evolução Molecular , Especiação Genética , Evolução Biológica , Análise de Sequência de DNARESUMO
BACKGROUND Severe anemia caused by hemorrhoidal hematochezia is typically treated preoperatively with reference to severe anemia treatment strategies from other etiologies. This retrospective cohort study included 128 patients with hemorrhoidal severe anemia admitted to 3 hospitals from September 1, 2018, to August 1, 2023, and aimed to evaluate preoperative blood transfusion requirements. MATERIAL AND METHODS Of 5120 patients with hemorrhoids, 128 (2.25%; male/female: 72/56) experienced hemorrhoidal severe anemia, transfusion, and Milligan-Morgan surgery. Patients were categorized into 2 groups based on their preoperative hemoglobin (PHB) levels after transfusion: PHB ≥70 g/L as the liberal-transfusion group (LG), and PHB <70 as the restrictive-threshold group (RG). The general condition, bleeding duration, hemoglobin level on admission, transfusion volume, length of stay, immune transfusion reaction, surgical duration, and hospitalization cost were compared between the 2 groups. RESULTS Patients with severe anemia (age: 41.07±14.76) tended to be younger than those with common hemorrhoids (age: 49.431±15.59 years). The LG had a significantly higher transfusion volume (4.77±2.22 units), frequency of immune transfusion reactions (1.22±0.58), and hospitalization costs (16.69±3.31 thousand yuan) than the RG, which had a transfusion volume of 3.77±2.09 units, frequency of immune transfusion reactions of 0.44±0.51, and hospitalization costs of 15.00±3.06 thousand yuan. Surgical duration in the LG (25.69±14.71 min) was significantly lower than that of the RG (35.24±18.72 min). CONCLUSIONS Patients with hemorrhoids with severe anemia might require a lower preoperative transfusion threshold than the currently recognized threshold, with an undifferentiated treatment effect and additional benefits.
Assuntos
Anemia , Transfusão de Sangue , Hemorroidas , Cuidados Pré-Operatórios , Humanos , Masculino , Feminino , Estudos Retrospectivos , Anemia/terapia , Anemia/etiologia , Transfusão de Sangue/métodos , Pessoa de Meia-Idade , Adulto , Hemorroidas/cirurgia , Hemorroidas/complicações , Cuidados Pré-Operatórios/métodos , Hemoglobinas/análise , Hemoglobinas/metabolismo , Tempo de Internação , Hemorragia Gastrointestinal/cirurgia , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , IdosoRESUMO
Kiwifruit (Actinidia chinensis) is one of the popular fruits world-wide, and its quality is mainly determined by key metabolites (sugars, flavonoids, and vitamins). Previous works on kiwifruit are mostly done via a single omics approach or involve only limited metabolites. Consequently, the dynamic metabolomes during kiwifruit development and ripening and the underlying regulatory mechanisms are poorly understood. In this study, using high-resolution metabolomic and transcriptomic analyses, we investigated kiwifruit metabolic landscapes at 11 different developmental and ripening stages and revealed a parallel classification of 515 metabolites and their co-expressed genes into 10 distinct metabolic vs gene modules (MM vs GM). Through integrative bioinformatics coupled with functional genomic assays, we constructed a global map and uncovered essential transcriptomic and transcriptional regulatory networks for all major metabolic changes that occurred throughout the kiwifruit growth cycle. Apart from known MM vs GM for metabolites such as soluble sugars, we identified novel transcription factors that regulate the accumulation of procyanidins, vitamin C, and other important metabolites. Our findings thus shed light on the kiwifruit metabolic regulatory network and provide a valuable resource for the designed improvement of kiwifruit quality.
Assuntos
Actinidia , Actinidia/genética , Actinidia/metabolismo , Frutas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Açúcares/metabolismo , Transcriptoma/genéticaRESUMO
A wearable sweat sensor, which could continuously monitor biomolecules related to the human physiological state, is emerging as a promising piece of health surveillance equipment. However, current sensors cannot simultaneously achieve a detection performance that equates to that of traditional sensors and satisfactory mechanical strength. Herein, a wearable sweat sensor with excellent detection performance and mechanical stability is designed and fabricated. Based on the integration of laser-induced graphene electrodes and a screen printing technique, this wearable sweat sensor could realize both the separate and simultaneous detection of uric acid (UA), tyrosine (Tyr), and ascorbic acid (AA) with high sensitivity. Good UA sensing performance in artificial sweat could be maintained even after 20 000 bends. In addition, the sensor can operate well in the wearing state or in a complex bovine whole blood sample. For the detection of human sweat, the changes in UA concentration after a purine-rich meal are continuously monitored and the results are in accordance with the corresponding serum UA detection results tested with a commercial serum UA meter. These results suggest its application potential in health monitoring for both gout patients and healthy humans.
Assuntos
Suor , Animais , Bovinos , Suor/química , Ácido Úrico/análise , Tirosina/análise , Ácido Ascórbico/análise , Humanos , Dispositivos Eletrônicos VestíveisRESUMO
BACKGROUND The high recurrence rate of perianal fistula Crohn's disease (PFCD) increases the need to protect the anal sphincter during each surgical treatment of fistulas. We aimed to evaluate the safety and efficacy of internal orifice alloy closure in patients with PFCD. MATERIAL AND METHODS Fifteen patients with PFCD were enrolled in the study between July 6, 2021, and April 27, 2023. All patients underwent preoperative colonoscopy and anal magnetic resonance examination for diagnosis and evaluation. Internal orifice alloy closure (IOAC) was performed only when Crohn's disease was in remission. The external sphincter had not been severed. Perianal magnetic resonance imaging examination was used for postoperative evaluation after 6 months. Fistula cure rate, length of stay, perianal pain, and Wexner incontinence score were retrospectively compared between 15 patients treated with IOAC and 40 patients treated with other surgical methods. RESULTS Fifteen patients (male/female: 9/6, age: 23.6±14.3 years) with PFCD were included (follow-up: 24 months). In total, 20.0% (3) had multiple tracts, and 13.3% (2) had a high anal fistula. Among them, 10 patients received biologics for induction for mucosal healing before surgery. The fistula healed completely in 80.0% (12/15) and did not heal in 20.0% (3/15). Three patients who did not heal underwent fistulotomy and eventually recovered. IOAC is not superior in terms of fistula healing rates, length of stay, and anal pain, but its Wexner incontinence scores are significantly lower than with other surgical methods. CONCLUSIONS IOAC is a novel sphincter-saving surgery that is effective and safe for the treatment of PFCD.
Assuntos
Doença de Crohn , Fístula Retal , Humanos , Feminino , Masculino , Criança , Adolescente , Adulto Jovem , Adulto , Doença de Crohn/complicações , Doença de Crohn/cirurgia , Estudos Retrospectivos , Fístula Retal/etiologia , Fístula Retal/cirurgia , Ligas , Dor PélvicaRESUMO
Object. ß-Elemene is an emerging antitumor Chinese medicine, but the exact mechanism of action of ß-elemene in colorectal cancer (CRC) remains unclear. This study aimed to explore the mechanism of the lncRNA-miRNA-mRNA network in the process of ß-elemene inhibiting CRC. Methods. RNA sequencing was performed on CRC cells from the control group (untreated) and the case group (ß-elemene-treated). According to the sequencing data, we screened the differentially expressed (DE) lncRNAs, miRNAs, and mRNAs and then analyzed them by functional enrichment analyses. Through the lncRNA-miRNA-mRNA network, the key miRNAs and mRNAs involved in the process of ß-elemene inhibiting CRC were further identified. Results. Totally, 607 upregulated and 599 downregulated DElncRNAs, 12 downregulated and 24 upregulated DEmiRNAs, and 3153 downregulated and 3248 upregulated DEmRNAs were identified. Through the lncRNA-miRNA-mRNA network, 3 miRNAs (miR-7109-3p, miR-4506, and miR-3182), 7 prognostic mRNAs (ALPG, DTX1, HOXD13, RIMS3, SLC16A8, SYT1, and TNNT1), and 2 key mRNAs (RIMS3 and SLC16A8) were determined to participate in the inhibitory mechanism of ß-elemene in CRC. Conclusion. This study revealed for the first time that the lncRNA-miRNA-mRNA network is involved in the regulation of ß-elemene in CRC, and these identified miRNAs and mRNAs could be new clinical prognostic biomarkers and therapeutic targets for CRC patients.
Assuntos
Neoplasias Colorretais , MicroRNAs , RNA Longo não Codificante , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Sesquiterpenos , Transcriptoma/genéticaRESUMO
OBJECTIVE: To investigate the effect of laparoscopic surgery in colorectal cancer (CRC) patients with natural orifice specimen extraction (NOSE) on the recovery and quality of life (QOL) of patients. MATERIAL AND METHODS: Ninety-two eligible patients were randomly assigned into two groups: the traditional laparoscopy group (L group, n = 46) and the laparoscopic transanal specimen extraction group (NL group, n = 46). General data, surgery-related indicators, postoperative recovery, and prognosis were compared and analyzed between the two groups. RESULTS: A total of 46 patients in each group were enrolled in this study. The general data and surgery-related indicators were comparable between the two groups (all p > .05). There were no significant differences in the time of first flatus, bleeding, obstruction, constipation, and infectious complications between the two groups (all p > .05). The differences in the incidence of postoperative diarrhea, pain degree, and satisfaction on the aesthetics of the abdominal wall showed significant differences (χ2 = 6.133, p = .013; χ2 = 12.116, p = .017; χ2 = 13.463, p = .004). The postoperative follow-up time was 3-53 months. There were no significant differences in the postoperative hospital stay, medical costs, hospital readmission rate, incidence of incisional hernia, overall survival, disease-free survival, and QOL between the two groups (all p > .05). Conclusion: Laparoscopic surgery with NOSE for eligible patients with CRC was a feasible choice.
Assuntos
Neoplasias Colorretais , Laparoscopia , Cirurgia Endoscópica por Orifício Natural , Neoplasias Colorretais/cirurgia , Humanos , Tempo de Internação , Complicações Pós-Operatórias/epidemiologia , Prognóstico , Qualidade de Vida , Resultado do TratamentoRESUMO
Polycomb group (PcG) proteins play vital roles in plant development via epigenetically repressing the transcription of target genes. However, to date, their function in fruit ripening is largely unknown. Combining reverse genetic approaches, physiological methods, yeast two-hybrid, co-immunoprecipitation, and chromatin immunoprecipitation assays, we show that Like Heterochromatin Protein 1b (SlLHP1b), a tomato Polycomb Repressive Complex 1 (PRC1)-like protein with a ripening-related expression pattern, represses fruit ripening via colocalization with epigenetic mark H3K27me3. RNA interference (RNAi)-mediated downregulation of SlLHP1b advanced ripening initiation, climacteric ethylene production, and fruit softening, whereas SlLHP1b overexpression delayed these events. Ripening-related genes were significantly upregulated in SlLHP1b RNAi fruits and downregulated in overexpressing fruits compared with wild-type. Furthermore, SlLHP1b protein interacts with ripening regulator MSI1, a subunit of the PRC2 complex. Moreover, SlLHP1b also binds the epigenetic histone mark H3K27me3 in vivo and chromatin immunoprecipitation-quantitative PCR results showed binding occurs preferentially to regions of ripening-associated chromatin marked by histone H3K27me3. Furthermore, the H3K27me3 levels in chromatin of ripening-related genes is negatively correlated with accumulation of their transcripts in SlLHP1b down or upregulated fruits during ripening. Our findings reveal a novel regulatory function of SlLHP1b in fruit and provide new insights into the PcG-mediated epigenetic regulation of climacteric fruit ripening.
Assuntos
Solanum lycopersicum , Epigênese Genética , Etilenos , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Heterocromatina/genética , Histonas , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismoRESUMO
Trichomes are epidermal protuberances on aerial parts of plants known to play an important role in biotic and abiotic stresses. To date, our knowledge of the regulation of trichome formation in crop species is very limited. Through phenotyping of the Solanum pennellii×S. lycopersicum (cv. M82) introgression population, we identified the SlbHLH95 transcription factor as a negative regulator of trichome formation in tomato. In line with this negative role, SlbHLH95 displayed a very low expression in stems where trichomes are present at high density. Overexpression of SlbHLH95 resulted in a dramatically reduced trichome density in stems and a significant down-regulation of a set of trichome-related genes. In addition to the lower trichome density, overexpressing lines also showed pleiotropic alterations affecting both vegetative and reproductive development. While most of these phenotypes were reminiscent of gibberellin (GA)-deficient phenotypes, expression studies showed that two GA biosynthesis genes, SlGA20ox2 and SlKS5, are significantly down-regulated in SlbHLH95-OE plants. Moreover, in line with a decrease in active GA content, the glabrous and dwarf phenotypes were rescued by exogenous GA treatment. In addition, yeast one-hybrid and transactivation assays revealed that SlbHLH95 represses the expression of SlGA20ox2 and SlKS5 via direct binding to their promoters. Taken together, our study established a link between SlbHLH95, GA, and trichome formation, and uncovered the role of this gene in modulating GA biosynthesis in tomato.
Assuntos
Solanum lycopersicum , Tricomas , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Regulação da Expressão Gênica de Plantas , Giberelinas , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Tricomas/genética , Tricomas/metabolismoRESUMO
Large volumes of data from material characterizations call for rapid and automatic data analysis to accelerate materials discovery. Herein, we report a convolutional neural network (CNN) that was trained based on theoretical data and very limited experimental data for fast identification of experimental X-ray diffraction (XRD) patterns of metal-organic frameworks (MOFs). To augment the data for training the model, noise was extracted from experimental data and shuffled; then it was merged with the main peaks that were extracted from theoretical spectra to synthesize new spectra. For the first time, one-to-one material identification was achieved. Theoretical MOFs patterns (1012) were augmented to a whole data set of 72â¯864 samples. It was then randomly shuffled and split into training (58â¯292 samples) and validation (14â¯572 samples) data sets at a ratio of 4:1. For the task of discriminating, the optimized model showed the highest identification accuracy of 96.7% for the top 5 ranking on a test data set of 30 hold-out samples. Neighborhood component analysis (NCA) on the experimental XRD samples shows that the samples from the same material are clustered in groups in the NCA map. Analysis on the class activation maps of the last CNN layer further discloses the mechanism by which the CNN model successfully identifies individual MOFs from the XRD patterns. This CNN model trained by the data augmentation technique would not only open numerous potential applications for identifying XRD patterns for different materials, but also pave avenues to autonomously analyze data by other characterization tools such as FTIR, Raman, and NMR spectroscopies.
Assuntos
Redes Neurais de Computação , Difração de Raios XRESUMO
Tubby-like proteins (TLPs), which were firstly identified in obese mice, play important roles in male gametophyte development, biotic stress response, and abiotic stress responses in plants. To date, the role of TLP genes in fruit ripening is largely unknown. Here, through a bioinformatics analysis, we identified 11 TLPs which can be divided into three subgroups in tomato (Solanum lycopersicum), a model plant for studying fruit development and ripening. It was shown that all SlTLPs except SlTLP11 contain both the Tub domain and F-box domain. An expression profiling analysis in different tomato tissues and developmental stages showed that 7 TLP genes are mainly expressed in vegetative tissues, flower, and early fruit developmental stages. Interestingly, other 4 TLP members (SlTLP1, SlTLP2, SlTLP4, and SlTLP5) were found to be highly expressed after breaker stage, suggesting a potential role of these genes in fruit ripening. Moreover, the induced expression of SlTLP1 and SlTLP2 by exogenous ethylene treatment and the down expression of the two genes in ripening mutants, further support their putative role in the ripening process. Overall, our study provides a basis for further investigation of the function of TLPs in plant development and fruit ripening.
Assuntos
Frutas/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Mutação , Proteínas de Plantas/genética , Solanum lycopersicum/genética , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Perfilação da Expressão Gênica , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Filogenia , Proteínas de Plantas/metabolismoRESUMO
Ethylene is instrumental to climacteric fruit ripening and EIN3 BINDING F-BOX (EBF) proteins have been assigned a central role in mediating ethylene responses by regulating EIN3/EIL degradation in Arabidopsis. However, the role and mode of action of tomato EBFs in ethylene-dependent processes like fruit ripening remains unclear. Two novel EBF genes, SlEBF3 and SlEBF4, were identified in the tomato genome, and SlEBF3 displayed a ripening-associated expression pattern suggesting its potential involvement in controlling ethylene response during fruit ripening. SlEBF3 downregulated tomato lines failed to show obvious ripening-related phenotypes likely due to functional redundancy among SlEBF family members. By contrast, SlEBF3 overexpression lines exhibited pleiotropic ethylene-related alterations, including inhibition of fruit ripening, attenuated triple-response and delayed petal abscission. Yeast-two-hybrid system and bimolecular fluorescence complementation approaches indicated that SlEBF3 interacts with all known tomato SlEIL proteins and, consistently, total SlEIL protein levels were decreased in SlEBF3 overexpression fruits, supporting the idea that the reduced ethylene sensitivity and defects in fruit ripening are due to the SlEBF3-mediated degradation of EIL proteins. Moreover, SlEBF3 expression is regulated by EIL1 via a feedback loop, which supposes its role in tuning ethylene signaling and responses. Overall, the study reveals the role of a novel EBF tomato gene in climacteric ripening, thus providing a new target for modulating fleshy fruit ripening.
RESUMO
3D electronic/optoelectronic devices have shown great potentials for various applications due to their unique properties inherited not only from functional materials, but also from 3D architectures. Although a variety of fabrication methods including mechanically guided assembly have been reported, the resulting 3D devices show no stimuli-responsive functions or are not free standing, thereby limiting their applications. Herein, the stimulus responsive assembly of complex 3D structures driven by temperature-responsive hydrogels is demonstrated for applications in 3D multifunctional sensors. The assembly driving force, compressive buckling, arises from the volume shrinkage of the responsive hydrogel substrates when they are heated above the lower critical solution temperature. Driven by the compressive buckling force, the 2D-formed membrane materials, which are pre-defined and selectively bonded to the substrates, are then assembled to 3D structures. They include "tent," "tower," "two-floor pavilion," "dome," "basket," and "nested-cages" with delicate geometries. Moreover, the demonstrated 3D bifunctional sensors based on laser induced graphene show capability of spatially resolved tactile sensing and temperature sensing. These multifunctional 3D sensors would open new applications in soft robotics, bioelectronics, micro-electromechanical systems, and others.
RESUMO
There is a significant need of advanced materials that can be fabricated into functional devices with defined three-dimensional (3D) structures for application in tissue engineering, flexible electronics, and soft robotics. This need motivates an emerging four-dimensional (4D) printing technology, by which printed 3D structures consisting of active materials can transform their configurations over time in response to stimuli. Despite the ubiquity of active materials in performing self-morphing processes, their potential for 4D printing has not been fully explored to date. In this study, we demonstrate 4D printing of a commercial polymer, SU-8, which has not been reported to date in this field. The working principle is based on a self-morphing process of the printed SU-8 structures through spatial control of the swelling medium inside the polymer matrix by a modified process. To understand the self-morphing behavior, fundamental studies on the effect of the geometries including contours and filling patterns were carried out. A soft electronic device as an actuator was demonstrated to realize an application of this programmable polymer using the 3D printing technology. These studies provide a new paradigm for application of SU-8 in 4D printing, paving a new route to the exploration of more potential candidates by this demonstrated strategy.