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1.
Dev Cell ; 59(10): 1345-1359.e6, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38579721

RESUMEN

The plant cell wall is a dynamic structure that plays an essential role in development, but the mechanism regulating cell wall formation remains poorly understood. We demonstrate that two transcription factors, SlERF.H5 and SlERF.H7, control cell wall formation and tomato fruit firmness in an additive manner. Knockout of SlERF.H5, SlERF.H7, or both genes decreased cell wall thickness, firmness, and cellulose contents in fruits during early development, especially in double-knockout lines. Overexpressing either gene resulted in thicker cell walls and greater fruit firmness with elevated cellulose levels in fruits but severely dwarf plants with lower gibberellin contents. We further identified that SlERF.H5 and SlERF.H7 activate the cellulose biosynthesis gene SlCESA3 but repress the gibberellin biosynthesis gene GA20ox1. Moreover, we identified a conserved LPL motif in these ERFs responsible for their activities as transcriptional activators and repressors, providing insight into how bifunctional transcription factors modulate distinct developmental processes.


Asunto(s)
Pared Celular , Frutas , Regulación de la Expresión Génica de las Plantas , Giberelinas , Proteínas de Plantas , Solanum lycopersicum , Factores de Transcripción , Solanum lycopersicum/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/crecimiento & desarrollo , Giberelinas/metabolismo , Pared Celular/metabolismo , Pared Celular/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Frutas/metabolismo , Frutas/genética , Frutas/crecimiento & desarrollo , Celulosa/metabolismo , Celulosa/biosíntesis , Plantas Modificadas Genéticamente/metabolismo , Secuencia Conservada , Secuencias de Aminoácidos
2.
Nat Commun ; 15(1): 2894, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570494

RESUMEN

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.


Asunto(s)
Solanaceae , Solanum lycopersicum , Solanum lycopersicum/genética , Domesticación , Fitomejoramiento , Esteroides
3.
J Integr Plant Biol ; 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38546046

RESUMEN

Carotenoids are important nutrients for human health that must be obtained from plants since they cannot be biosynthesized by the human body. Dissecting the regulatory mechanism of carotenoid metabolism in plants represents the first step toward manipulating carotenoid contents in plants by molecular design breeding. In this study, we determined that SlAP2c, an APETALA2 (AP2) family member, acts as a transcriptional repressor to regulate carotenoid biosynthesis in tomato (Solanum lycopersicum). Knockout of SlAP2c in both the "MicroTom" and "Ailsa Craig" backgrounds resulted in greater lycopene accumulation, whereas overexpression of this gene led to orange-ripe fruit with significantly lower lycopene contents than the wild type. We established that SlAP2c represses the expression of genes involved in lycopene biosynthesis by directly binding to the cis-elements in their promoters. Moreover, SlAP2c relies on its EAR motif to recruit the co-repressors TOPLESS (TPL)2/4 and forms a complex with histone deacetylase (had)1/3, thereby reducing the histone acetylation levels of lycopene biosynthesis genes. Furthermore, SlAP2a, a homolog of SlAP2c, acts upstream of SlAP2c and alleviates the SlAP2c-induced repression of lycopene biosynthesis genes by inhibiting SlAP2c transcription during fruit ripening. Therefore, we identified a transcriptional cascade mediated by AP2 family members that regulates lycopene biosynthesis during fruit ripening in tomato, laying the foundation for the manipulation of carotenoid metabolism in plants.

4.
New Phytol ; 242(2): 592-609, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38402567

RESUMEN

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.


Asunto(s)
Frutas , Solanum lycopersicum , Frutas/metabolismo , Solanum lycopersicum/genética , Etilenos/metabolismo , Botrytis/fisiología , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas
5.
Ocul Immunol Inflamm ; : 1-13, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38363334

RESUMEN

PURPOSE: To evaluate dry eye severity and ocular surface inflammation in autoimmune rheumatic diseases (ARDs). METHODS: Seventy-nine patients with ARDs were enrolled, including 26 patients with rheumatoid arthritis (RA), 33 patients with systemic lupus erythematosus (SLE), and 20 patients with primary Sjögren's syndrome (pSS). All patients underwent ocular surface evaluations, including ocular surface symptoms, signs, conjunctival impression cytology, and tear multicytokine detection. Systemic conditions, including disease duration, disease activity, and serological parameters, were also noted. RESULTS: SLE patients had the shortest disease duration, and nearly half of them had low disease activity, while RA patients and pSS patients had a relatively long disease duration, and approximately 90% of them had moderate or high disease activity. The incidence of dry eye and the levels of the proinflammatory tear cytokines in SLE were significantly lower than those in RA and pSS. However, ocular surface squamous metaplasia was more severe in SLE and pSS than in RA. Dry eye severity in all ARD patients was shown to be independent of disease activity, while Nelson's grades were positively correlated with disease duration in RA patients. Disease-related serological parameters were associated with tear proinflammatory cytokines in all ARD patients. CONCLUSIONS: Variable degrees of dry eye and immune-mediated ocular surface inflammation persist in different ARD patients. In addition to a well-known association between dry eye and pSS, dry eye is also commonly observed in SLE and RA patients. Therefore, there is a definite need for regular ophthalmologic evaluations and topical medications in all patients with ARDs.

6.
Hortic Res ; 11(2): uhad275, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38344652

RESUMEN

The phytohormone ethylene is well known for its important role in the ripening of climacteric fruit, such as tomato (Solanum lycopersicum). However, the role and mode of action of other plant hormones in climacteric fruit ripening regulation are not fully understood. Here, we showed that exogenous GA treatment or increasing endogenous gibberellin content by overexpressing the gibberellin synthesis gene SlGA3ox2 specifically in fruit tissues delayed tomato fruit ripening, whereas treatment with the GA biosynthesis inhibitor paclobutrazol (PAC) accelerated fruit ripening. Moreover, exogenous ethylene treatment cannot completely reverse the delayed fruit ripening phenotype. Furthermore, exogenous GA treatment of ethylene signalling mutant Never ripe (Nr) or SlEBF3-overexpressing lines still delayed fruit ripening, suggesting that GA involved in fruit ripening partially depends on ethylene. Transcriptome profiling showed that gibberellin affect the ripening of fruits by modulating the metabolism and signal transduction of multiple plant hormones, such as auxin and abscisic acid, in addition to ethylene. Overall, the results of this study provide new insight into the regulation of gibberellin in fruit ripening through mediating multiple hormone signals.

7.
Plant J ; 115(6): 1746-1757, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37326247

RESUMEN

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.


Asunto(s)
Solanum lycopersicum , Solanum lycopersicum/genética , Frutas/genética , Frutas/metabolismo , Botrytis/metabolismo , Flavonoides/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas
8.
New Phytol ; 239(3): 949-963, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37247338

RESUMEN

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.


Asunto(s)
Ácido Abscísico , Solanum lycopersicum , Humanos , Solanum lycopersicum/genética , Ácidos Indolacéticos , Ácido Ascórbico , Antioxidantes/metabolismo , Regulación de la Expresión Génica de las Plantas
9.
Hortic Res ; 10(3): uhac286, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36938568

RESUMEN

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.

10.
Horm Metab Res ; 55(4): 256-265, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36796411

RESUMEN

The metabolic score for insulin resistance (METS-IR) is a recently developed parameter for screening of metabolic disorder. However, the association between METS-IR and risk of hypertension in general adult population remains not fully determined. A meta-analysis was therefore performed. Observational studies evaluating the association between METS-IR and hypertension in adults were retrieved by searching PubMed, Embase, and Web of Science databases from inception to October 10, 2022. A random-effects model, which incorporates the potential influence of heterogeneity, was used to pool the results. Eight studies with 305 341 adults were included in the meta-analysis, and 47 887 (15.7%) of them had hypertension. Pooled results showed that a higher METS-IR was associated with hypertension after adjusting for multiple conventional risk factors [relative risk (RR) for highest versus lowest category of METS-IR: 1.67, 95% confidence interval (CI): 1.53 to 1.83, p<0.001, I2=8%]. The results were consistent in subgroup analyses according to study design, source of the cohort, age, sex, body mass index of the participants, and quality scores of the study (p for subgroup difference all>0.05). Results of meta-analysis with METS-IR analyzed in continuous variables also showed that METS-IR was associated with the risk of hypertension (RR for 1-unit increment of METS-IR: 1.15, 95% CI: 1.08 to 1.23, p<0.001, I2=79%). In conclusion, a high METS-IR is associated with hypertension in general adult population. Measuring METS-IR may be useful for screening participants at high risk of hypertension.


Asunto(s)
Hipertensión , Resistencia a la Insulina , Síndrome Metabólico , Adulto , Humanos , Síndrome Metabólico/epidemiología , Factores de Riesgo , Hipertensión/epidemiología , Índice de Masa Corporal
11.
BMC Ophthalmol ; 22(1): 437, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36376805

RESUMEN

BACKGROUND: Autoimmune blistering skin diseases (AIBD) are a group of rare chronic autoimmune diseases which are associated with ocular surface diseases especially dry eye disease. This study is designed to investigate the relationship between ocular surface disorders and quality of life among patients with autoimmune blistering skin diseases. METHODS: Twenty-four AIBD patients (18 pemphigus and 7 pemphigoid) and twenty-five non-AIBD controls were included. Ocular surface disease index (OSDI), ocular surface evaluation, including slit-lamp examination, Schirmer I test, tear break-up time, corneal fluorescein staining, lid-parallel conjunctival folds, meibomian gland evaluation, presence of symblepharon and corneal opacity were assessed. Life quality was evaluated by multiple questionnaires, including Medical Outcomes Study 36-Item Short Form Questionnaire (SF-36), Hospital Anxiety and Depression Scale (HADS), Pittsburgh Sleep Quality Index (PSQI) and Health Assessment Questionnaire-Disability Index (HAQ-DI). Ocular surface tests and quality of life were compared between AIBD patients and non-AIBD controls. In the AIBD patients, the associations between ocular surface parameters and quality of life were also evaluated. RESULTS: 92% of AIBD patients and 87.5% of age- and sex-matched non-AIBD controls were diagnosed with dry eye in this study. Compared with non-AIBD controls, AIBD patients reported lower SF-36 scores (P < 0.05) and severer OSDI, Schirmer I test, tear break-up time, corneal fluorescein staining, presence of symblepharon and corneal opacity measures (P < 0.05). OSDI, Schirmer I test were correlated with SF-36 composite scores or scores on the SF-36 subscales. CONCLUSIONS: AIBD patients experience reduced quality of life and more severe ocular surface disorders including dry eye, symblepharon and corneal opacity. Early treatments of dry eye and collaborations among multidisciplinary physicians are necessary in patients with AIBD.


Asunto(s)
Enfermedades Autoinmunes , Opacidad de la Córnea , Síndromes de Ojo Seco , Enfermedades de los Párpados , Enfermedades de la Piel , Humanos , Calidad de Vida , Estudios Transversales , Glándulas Tarsales , Lágrimas , Síndromes de Ojo Seco/diagnóstico , Enfermedades de los Párpados/diagnóstico , Fluoresceína , Encuestas y Cuestionarios , Enfermedades Autoinmunes/complicaciones , Vesícula
12.
BMC Public Health ; 22(1): 1871, 2022 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-36207704

RESUMEN

AIMS: To investigate the proportion and risk factors of diabetic retinopathy (DR) by stages in less-developed rural areas in Hunan Province of China. BACKGROUND: DR is common among people with diabetes but not well recognized in less-developed rural areas. There is insufficient evidence on the risk factors of DR by stages, making it challenging to develop targeted prevention and intervention programs for DR in primary care settings. METHODS: A multi-site cross-sectional survey was conducted among people with type 2 diabetes mellitus (T2DM) from four less-developed counties in Hunan Province of China. All participants underwent the screening of DR via digital fundus photography and completed self-reported questionnaires on their socio-demographic and clinical characteristics, diabetes self-efficacy, diabetes self-care behaviors, social support, family function, and health service accessibility. The multinomial logistic regression models were employed to explore the risk factors of DR by stage, which were selected based on the socio-ecological model, literature, and clinical experience. RESULTS: A total of 196 participants were included in this study with an average age of 57.43 ± 10.26. 59.6% (117/196) of the participants were identified as DR, including 37.2% (73/196) non-proliferative DR and 22.4% (44/196) proliferative DR. Compared to the non-DR group, the risk factors of non-proliferative DR and proliferative DR were diabetes duration (OR: 1.10, 95 CI%: 1.04-1.17; OR: 1.14, 95 CI% 1.06-1.22) and self-monitoring of blood glucose (OR: 1.09, 95 CI% 1.01-1.17; OR: 1.11, 95 CI%: 1.02-1.20); the protective factors of non-proliferative DR was accessible complication prevention and management education (OR: 0.37, 95 CI% 0.14-0.94) while the protective factors of proliferative DR were physical activities (OR: 0.89, 95 CI%: 0.80-0.98). Compared to the non-proliferative DR group, the protective factors of proliferative DR were physical activities (OR: 0.89, 95 CI% 0.02-0.89) and family function (OR: 0.84, 95 CI%: 0.04-0.84). CONCLUSION: DR was prevalent among people with T2DM in less-developed rural areas, indicating the need of strengthening DR screening. Risk factors of DR varied by stage while sharing some common factors. Future DR prevention and intervention programs may benefit from improving these factors to reduce the risk of DR by stage.


Asunto(s)
Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Anciano , Glucemia , China/epidemiología , Estudios Transversales , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/epidemiología , Humanos , Persona de Mediana Edad , Prevalencia , Factores de Riesgo
13.
Plant Cell ; 34(11): 4409-4427, 2022 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-36000899

RESUMEN

Ascorbic acid (AsA) is a multifunctional phytonutrient that is essential for the human diet as well as plant development. While much is known about AsA biosynthesis in plants, how this process is regulated in tomato (Solanum lycopersicum) fruits remains unclear. Here, we found that auxin treatment inhibited AsA accumulation in the leaves and pericarps of tomato. The auxin response factor gene SlARF4 is induced by auxin to mediate auxin-induced inhibition of AsA accumulation. Specifically, SlARF4 transcriptionally inhibits the transcription factor gene SlMYB11, thereby modulating AsA accumulation by regulating the transcription of the AsA biosynthesis genes l-galactose-1-phosphate phosphatase, l-galactono-1,4-lactone dehydrogenase, and dehydroascorbate. By contrast, abscisic acid (ABA) treatment increased AsA accumulation in tomato under drought stress. ABA induced the expression of the mitogen-activated protein kinase gene SlMAPK8. We demonstrate that SlMAPK8 phosphorylates SlARF4 and inhibits its transcriptional activity, whereas SlMAPK8 phosphorylates SlMYB11 and activates its transcriptional activity. SlMAPK8 functions in ABA-induced AsA accumulation and drought stress tolerance. Moreover, ABA antagonizes the effects of auxin on AsA biosynthesis. Therefore, auxin- and ABA-induced regulation of AsA accumulation is mediated by the SlMAPK8-SlARF4-SlMYB11 module in tomato during fruit development and drought stress responses, shedding light on the roles of phytohormones in regulating AsA accumulation to mediate stress tolerance.


Asunto(s)
Ácido Abscísico , Ácido Ascórbico , Sequías , Ácidos Indolacéticos , Proteínas de Plantas , Solanum lycopersicum , Estrés Fisiológico , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Ácido Ascórbico/biosíntesis , Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
14.
Hortic Res ; 9: uhac039, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35531317

RESUMEN

Low temperatures are known to destroy cell membranes' structural integrity by affecting the remodeling of their phospholipids. Fruits stored at low temperature are prone to chilling injury, characterized by discoloration, absence of ripening, surface pitting, growth inhibition, flavor loss, decay, and wilting. Phosphatidic acid, a vital second-messenger lipid in plants, is known to accumulate in response to different kinds of stress stimuli. However, the regulatory mechanism of its production from the degradation of phospholipids remains poorly understood. We identified two cold-responsive NAC (NAM/ATAF1/CUC2) transcription factors from bananas, namely, MaNAC25 and MaNAC28, which negatively regulated cold tolerance in banana fruits by upregulating the expression of phospholipid degradation genes in banana fruits. Furthermore, MaNAC25 and MaNAC28 formed a positive feedback loop to induce phospholipid degradation and produce phosphatidic acid. In contrast, ethylene directly inhibited the degradation of phospholipids in banana and transgenic tomato fruits. In addition, ethylene reduced the activity of MaNAC25 and MaNAC28, thereby inhibiting phospholipid degradation. To conclude, NAC-mediated membrane lipid remodeling negatively regulates the cold tolerance of banana and transgenic tomato fruits.

15.
Plant Biotechnol J ; 20(6): 1213-1225, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35258157

RESUMEN

Postharvest deterioration is among the major challenges for the fruit industry. Regulation of the fruit softening rate is an effective strategy for extending shelf-life and reducing the economic losses due postharvest deterioration. The tomato myoinositol monophosphatase 3 gene SlIMP3, which showed highest expression level in fruit, was expressed and purified. SlIMP3 demonstrated high affinity with the L-Gal 1-P and D-Ins 3-P, and acted as a bifunctional enzyme in the biosynthesis of AsA and myoinositol. Overexpression of SlIMP3 not only improved AsA and myoinositol content, but also increased cell wall thickness, improved fruit firmness, delayed fruit softening, decreased water loss, and extended shelf-life. Overexpression of SlIMP3 also increased uronic acid, rhamnose, xylose, mannose, and galactose content in cell wall of fruit. Treating fruit with myoinositol obtained similar fruit phenotypes of SlIMP3-overexpressed fruit, with increased cell wall thickness and delayed fruit softening. Meanwhile, overexpression of SlIMP3 conferred tomato fruit tolerance to Botrytis cinerea. The function of SlIMP3 in cell wall biogenesis and fruit softening were also verified using another tomato species, Ailsa Craig (AC). Overexpression of SlDHAR in fruit increased AsA content, but did not affect the cell wall thickness or fruit firmness and softening. The results support a critical role for SlIMP3 in AsA biosynthesis and cell wall biogenesis, and provide a new method of delaying tomato fruit softening, and insight into the link between AsA and cell wall metabolism.


Asunto(s)
Solanum lycopersicum , Ácido Ascórbico , Pared Celular/metabolismo , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Inositol/metabolismo , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
16.
Hortic Res ; 8(1): 259, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34848692

RESUMEN

Chlorophylls and carotenoids are essential and beneficial substances for both plant and human health. Identifying the regulatory network of these pigments is necessary for improving fruit quality. In a previous study, we identified an R2R3-MYB transcription factor, SlMYB72, that plays an important role in chlorophyll and carotenoid metabolism in tomato fruit. Here, we demonstrated that the SlMYB72-interacting protein SlZHD17, which belongs to the zinc-finger homeodomain transcription factor family, also functions in chlorophyll and carotenoid metabolism. Silencing SlZHD17 in tomato improved multiple beneficial agronomic traits, including dwarfism, accelerated flowering, and earlier fruit harvest. More importantly, downregulating SlZHD17 in fruits resulted in larger chloroplasts and a higher chlorophyll content. Dual-luciferase, yeast one-hybrid and electrophoretic mobility shift assays clarified that SlZHD17 regulates the chlorophyll biosynthesis gene SlPOR-B and chloroplast developmental regulator SlTKN2 in a direct manner. Chlorophyll degradation and plastid transformation were also retarded after suppression of SlZHD17 in fruits, which was caused by the inhibition of SlSGR1, a crucial factor in chlorophyll degradation. On the other hand, the expression of the carotenoid biosynthesis genes SlPSY1 and SlZISO was also suppressed and directly regulated by SlZHD17, which induced uneven pigmentation and decreased the lycopene content in fruits with SlZHD17 suppression at the ripe stage. Furthermore, the protein-protein interactions between SlZHD17 and other pigment regulators, including SlARF4, SlBEL11, and SlTAGL1, were also presented. This study provides new insight into the complex pigment regulatory network and provides new options for breeding strategies aiming to improve fruit quality.

17.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-34707009

RESUMEN

OBJECTIVES: The main purpose of cochlear implantation for prelingual deafness is to restore the deaf children's auditory function, obtain normal speech development, learning and social ability, and improve the quality of life. Previous studies mostly focused on the improvement of simple hearing or speech ability. This study aims to evaluate the changes of hearing and speech ability and family life quality of patients after cochlear implantation, and to explore the effect of cochlear implantation on hearing and speech rehabilitation of patients. METHODS: In February 2021, using the convenient sampling method, 171 patients who have completed cochlear implantation were selected from the database of cochlear implantation follow-up center of a class III Tertiary hospital in Hunan Province. Questionnaires were used to investigate the patients' parents, which were Categories of Auditory Performance (CAP), Speech/Spatial and Qualities of Hearing Scale-Parents' Version (SSQ-P), and Children using Hearing Implants Quality of Life (CuHI-QoL). T-test and analysis of variance were used to explore the postoperative auditory and speech ability of patients at different ages in different periods (<2.5-year group, 2.5-4.5-year group and >4.5-year group), and Pearson correlation analysis was used to explore the correlation. Multiple linear regression was used to explore the relationship between the dimension of patients' quality of life and the scores of scale for evaluating auditory ability (CAP, speech perception, spatial hearing, and other hearing characteristics). RESULTS: The values of CAP and SSQ-P in the <2.5-year group were lower than those in the 2.5-4.5-year and >4.5-year groups (all P<0.05). Pearson correlation analysis showed that postoperative years and CuHI-QoL scores (parental expectations and patients' quality of life) were positively correlated with score of CAP, SSQ-P and its dimension, respectively (all P<0.05). The results of multiple linear regression analysis showed the CAP scores and speech perception were the influencing factors for the quality of life (R2=0.170, P<0.01). CONCLUSIONS: Two and a half years after operation is the rapid growth period of patients' hearing and language ability, and the growth rate becomes slow after stabilization. With the extension of postoperative years, the patients' hearing and speech ability becomes stronger, and the quality of life is better.


Asunto(s)
Implantación Coclear , Implantes Cocleares , Sordera , Percepción del Habla , Niño , Sordera/cirugía , Audición , Humanos , Calidad de Vida , Habla , Resultado del Tratamiento
18.
J Exp Bot ; 72(10): 3806-3820, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33619530

RESUMEN

Tomato trichomes act as a mechanical and chemical barrier against pests. An R2R3 MYB transcription factor gene, SlMYB75, is highly expressed in type II, V, and VI trichomes. SlMYB75 protein is located in the nucleus and possesses transcriptional activation activity. Down-regulation of SlMYB75 increased the formation of type II, V, and VI trichomes, accumulation of δ-elemene, ß-caryophyllene, and α-humulene in glandular trichomes, and tolerance to spider mites in tomato. In contrast, overexpression of SlMYB75 inhibited trichome formation and sesquiterpene accumulation, and increased plant sensitivity to spider mites. RNA-Seq analyses of the SlMYB75 RNAi line indicated massive perturbation of the transcriptome, with a significant impact on several classes of transcription factors. Expression of the MYB genes SlMYB52 and SlTHM1 was strongly reduced in the RNAi line and increased in the SlMYB75-overexpressing line. SlMYB75 protein interacted with SlMYB52 and SlTHM1 and activated their expression. SlMYB75 directly targeted the promoter of the cyclin gene SlCycB2, increasing its activity. The auxin response factor SlARF4 directly targeted the promoter of SlMYB75 and inhibited its expression. SlMYB75 also bound to the promoters of the terpene synthase genes SlTPS12, SlTPS31, and SlTPS35, inhibiting their transcription. Our findings indicate that SlMYB75 perturbation affects several transcriptional circuits, resulting in altered trichome density and metabolic content.


Asunto(s)
Proteínas de Plantas , Sesquiterpenos/metabolismo , Solanum lycopersicum , Factores de Transcripción , Tricomas/crecimiento & desarrollo , Animales , Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
19.
Plant Biotechnol J ; 19(1): 138-152, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32654333

RESUMEN

Unicellular and multicellular tomato trichomes function as mechanical and chemical barriers against herbivores. Auxin treatment increased the formation of II, V and VI type trichomes in tomato leaves. The auxin response factor gene SlARF4, which was highly expressed in II, V and VI type trichomes, positively regulated the auxin-induced formation of II, V and VI type trichomes in the tomato leaves. SlARF4 overexpression plants with high densities of these trichomes exhibited tolerance to spider mites. Two R2R3 MYB genes, SlTHM1 and SlMYB52, were directly targeted and inhibited by SlARF4. SlTHM1 was specifically expressed in II and VI type trichomes and negatively regulated the auxin-induced formation of II and VI type trichomes in the tomato leaves. SlTHM1 down-regulation plants with high densities of II and VI type trichomes also showed tolerance to spider mites. SlMYB52 was specifically expressed in V type trichomes and negatively regulated the auxin-induced formation of V type trichome in the tomato leaves. The regulation of SlARF4 on the formation of II, V and VI type trichomes depended on SlTHM1 and SlMYB52, which directly targeted cyclin gene SlCycB2 and increased its expression. In conclusion, our data indicates that the R2R3 MYB-dependent auxin signalling pathway regulates the formation of II, V and VI type trichomes in tomato leaves. Our study provides an effective method for improving the tolerance of tomato to spider mites.


Asunto(s)
Solanum lycopersicum , Tetranychidae , Animales , Regulación de la Expresión Génica de las Plantas/genética , Ácidos Indolacéticos , Solanum lycopersicum/genética , Hojas de la Planta/genética , Tetranychidae/genética , Tricomas
20.
Am J Transplant ; 21(2): 552-566, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32892499

RESUMEN

Myeloid-derived suppressor cells (MDSC) are one of the major negative regulators of immune responses during many pathological conditions such as cancer and transplantation. Emerging evidence indicates that MDSC also contribute to tumor progression through their pro-angiogenic activity in addition to immunosuppressive function. However, virtually nothing is known about the role of MDSC in the regulation of neovascularization after transplantation. Here we showed that antibody-mediated depletion of MDSC in mice led to robust growth of blood and lymphatic neovessels and rapid allograft rejection after corneal penetrating keratoplasty. In contrast, adoptive transfer of ex vivo generated MDSC from cytokine-treated bone marrow cells (evMDSC) suppressed neovascularization and prolonged corneal allograft survival in an inducible nitric oxide synthase (iNOS)-dependent manner. Mechanistically, compared to naïve MDSC control, evMDSC have increased expression of an anti-angiogenic factor thrombospondin 1 (Tsp-1) and decreased expression of two critical pro-angiogenic factors, vascular endothelial growth factor A (VEGF-A), and VEGF-C. These findings demonstrate MDSC as a critical anti-angiogenic regulator during transplantation. Our study also indicates that evMDSC are a valuable candidate agent for development of novel cell therapy to improve allograft survival after transplantation.


Asunto(s)
Trasplante de Córnea , Células Supresoras de Origen Mieloide , Animales , Supervivencia de Injerto , Linfangiogénesis , Ratones , Ratones Endogámicos C57BL , Trombospondina 1 , Factor A de Crecimiento Endotelial Vascular , Factor C de Crecimiento Endotelial Vascular
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