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1.
Annu Rev Cell Dev Biol ; 35: 407-431, 2019 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-31403819

RESUMEN

A large and significant portion of eukaryotic transcriptomes consists of noncoding RNAs (ncRNAs) that have minimal or no protein-coding capacity but are functional. Diverse ncRNAs, including both small RNAs and long ncRNAs (lncRNAs), play essential regulatory roles in almost all biological processes by modulating gene expression at the transcriptional and posttranscriptional levels. In this review, we summarize the current knowledge of plant small RNAs and lncRNAs, with a focus on their biogenesis, modes of action, local and systemic movement, and functions at the nexus of plant development and environmental responses. The complex connections among small RNAs, lncRNAs, and small peptides in plants are also discussed, along with the challenges of identifying and investigating new classes of ncRNAs.


Asunto(s)
Desarrollo de la Planta/genética , Plantas/genética , ARN Largo no Codificante/metabolismo , ARN de Planta/metabolismo , Estrés Fisiológico/genética , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , MicroARNs/genética , MicroARNs/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , ARN Largo no Codificante/genética , ARN de Planta/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo
2.
Mol Cell ; 81(21): 4493-4508.e9, 2021 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-34555354

RESUMEN

Initiation is the rate-limiting step in translation, and its dysregulation is vital for carcinogenesis, including hematopoietic malignancy. Thus, discovery of novel translation initiation regulators may provide promising therapeutic targets. Here, combining Ribo-seq, mass spectrometry, and RNA-seq datasets, we discovered an oncomicropeptide, APPLE (a peptide located in ER), encoded by a non-coding RNA transcript in acute myeloid leukemia (AML). APPLE is overexpressed in various subtypes of AML and confers a poor prognosis. The micropeptide is enriched in ribosomes and regulates the initiation step to enhance translation and to maintain high rates of oncoprotein synthesis. Mechanically, APPLE promotes PABPC1-eIF4G interaction and facilitates mRNA circularization and eIF4F initiation complex assembly to support a specific pro-cancer translation program. Targeting APPLE exhibited broad anti-cancer effects in vitro and in vivo. This study not only reports a previously unknown function of micropeptides but also provides new opportunities for targeting the translation machinery in cancer cells.


Asunto(s)
Factor 4F Eucariótico de Iniciación/química , Factor 4G Eucariótico de Iniciación/metabolismo , Neoplasias Hematológicas/metabolismo , Péptidos/química , Biosíntesis de Proteínas , Animales , Progresión de la Enfermedad , Genoma Humano , Células HEK293 , Humanos , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Sistemas de Lectura Abierta , Polirribosomas/química , ARN Mensajero/metabolismo , ARN no Traducido/metabolismo , Proteínas de Unión al ARN/genética , Ribosomas/metabolismo , Sensibilidad y Especificidad , Resultado del Tratamiento
3.
Plant Cell ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38735686

RESUMEN

Increasing grain yield is a major goal of breeders due to the rising global demand for food. We previously reported that the miR397-LACCASE (OsLAC) module regulates brassinosteroid (BR) signaling and grain yield in rice (Oryza sativa). However, the precise roles of laccase enzymes in the BR pathway remain unclear. Here, we report that OsLAC controls grain yield by preventing the turnover of TRANSTHYRETIN-LIKE (OsTTL), a negative regulator of BR signaling. Overexpressing OsTTL decreased BR sensitivity in rice, while loss-of-function of OsTTL led to enhanced BR signaling and increased grain yield. OsLAC directly binds to OsTTL and regulates its phosphorylation-mediated turnover. The phosphorylation site Ser226 of OsTTL is essential for its ubiquitination and degradation. Overexpressing the dephosphorylation-mimic form of OsTTL (OsTTLS226A) resulted in more severe defects than did overexpressing OsTTL. These findings provide insight into the role of an ancient laccase in BR signaling and suggest that the OsLAC-OsTTL module could serve as a target for improving grain yield.

4.
Plant Physiol ; 194(4): 2101-2116, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-37995372

RESUMEN

The precise timing of flowering plays a pivotal role in ensuring successful plant reproduction and seed production. This process is intricately governed by complex genetic networks that integrate internal and external signals. This study delved into the regulatory function of microRNA397 (miR397) and its target gene LACCASE-15 (OsLAC15) in modulating flowering traits in rice (Oryza sativa). Overexpression of miR397 led to earlier heading dates, decreased number of leaves on the main stem, and accelerated differentiation of the spikelet meristem. Conversely, overexpression of OsLAC15 resulted in delayed flowering and prolonged vegetative growth. Through biochemical and physiological assays, we uncovered that miR397-OsLAC15 had a profound impact on carbohydrate accumulation and photosynthetic assimilation, consequently enhancing the photosynthetic intensity in miR397-overexpressing rice plants. Notably, we identified that OsLAC15 is at least partially localized within the peroxisome organelle, where it regulates the photorespiration pathway. Moreover, we observed that a high CO2 concentration could rescue the late flowering phenotype in OsLAC15-overexpressing plants. These findings shed valuable insights into the regulatory mechanisms of miR397-OsLAC15 in rice flowering and provided potential strategies for developing crop varieties with early flowering and high-yield traits through genetic breeding.


Asunto(s)
Oryza , Oryza/metabolismo , Flores/fisiología , Fitomejoramiento , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Reproducción , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas
5.
Stem Cells ; 42(1): 64-75, 2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-37847598

RESUMEN

PURPOSE: This study aimed to investigate the effect of mesenchymal stem cell (MSC)-derived small extracellular vesicles (sEVs) on diabetic retinopathy (DR) and its underlying mechanism. METHODS: In vivo, MSC-sEVs were injected intravitreally into diabetic rats to determine the therapeutic efficacy. In vitro, MSC-sEVs with/without miR-22-3p inhibition were cocultured with advanced glycation end-products (AGEs)-induced microglia with/without NLRP3 overexpression to explore the molecular mechanism. RESULTS: In vivo, MSC-sEVs inhibited NLRP3 inflammasome activation, suppressed microglial activation, decreased inflammatory cytokines levels in the retina, and alleviated DR as evidenced by improved histological morphology and blood-retinal barrier function. Based on miRNA sequencing of MSC-sEVs, bioinformatic software, and dual-luciferase reporter assay, miR-22-3p stood out as the critical molecule for the role of MSC-sEVs in regulating NLRP3 inflammasome activation. Diabetic rats had lower level of miR-22-3p in their retina than those of control and sEV-treated rats. Confocal microscopy revealed that sEV could be internalized by microglia both in vivo and in vitro. In vitro, compared with sEV, the anti-inflammation effect of sEVmiR-22-3p(-) on AGEs-induced microglia was compromised, as they gave a lower suppression of NLRP3 inflammasome activation and inflammatory cytokines. In addition, NLRP3 overexpression in microglia damped the anti-inflammatory effect of sEV. CONCLUSION: These results indicated that MSC-sEVs alleviated DR via delivering miR-22-3p to inhibit NLRP3 inflammasome activation. Our findings indicate that MSC-sEVs might be a potential therapeutic method for DR.


Asunto(s)
Diabetes Mellitus Experimental , Retinopatía Diabética , Vesículas Extracelulares , Células Madre Mesenquimatosas , MicroARNs , Ratas , Animales , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Inflamasomas/genética , Retinopatía Diabética/genética , Retinopatía Diabética/terapia , MicroARNs/genética , Citocinas
6.
EMBO Rep ; 24(3): e55762, 2023 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-36597993

RESUMEN

N6 -Methyladenosine (m6 A) is an important RNA modification catalyzed by methyltransferase-like 3 (METTL3) and METTL14. m6 A homeostasis mediated by the methyltransferase (MTase) complex plays key roles in various biological processes. However, the mechanism underlying METTL14 protein stability and its role in m6 A homeostasis remain elusive. Here, we show that METTL14 stability is regulated by the competitive interaction of METTL3 with the E3 ligase STUB1. STUB1 directly interacts with METTL14 to mediate its ubiquitination at lysine residues K148, K156, and K162 for subsequent degradation, resulting in a significant decrease in total m6 A levels. The amino acid regions 450-454 and 464-480 of METTL3 are essential to promote METTL14 stabilization. Changes in STUB1 expression affect METTL14 protein levels, m6 A modification and tumorigenesis. Collectively, our findings uncover an ubiquitination mechanism controlling METTL14 protein levels to fine-tune m6 A homeostasis. Finally, we present evidence that modulating STUB1 expression to degrade METTL14 could represent a promising therapeutic strategy against cancer.


Asunto(s)
Adenosina , Metiltransferasas , Adenosina/metabolismo , Metiltransferasas/genética , Homeostasis
7.
Plant Cell ; 33(8): 2685-2700, 2021 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-34003932

RESUMEN

MEIOSIS ARRESTED AT LEPTOTENE1 (MEL1), a rice (Oryza sativa) Argonaute (AGO) protein, has been reported to function specifically at premeiotic and meiotic stages of germ cell development and is associated with a novel class of germ cell-specific small noncoding RNAs called phased small RNAs (phasiRNAs). MEL1 accumulation is temporally and spatially regulated and is eliminated after meiosis. However, the metabolism and turnover (i.e. the homeostasis) of MEL1 during germ cell development remains unknown. Here, we show that MEL1 is ubiquitinated and subsequently degraded via the proteasome pathway in vivo during late sporogenesis. Abnormal accumulation of MEL1 after meiosis leads to a semi-sterile phenotype. We identified a monocot-specific E3 ligase, XBOS36, a CULLIN RING-box protein, that is responsible for the degradation of MEL1. Ubiquitination at four K residues at the N terminus of MEL1 by XBOS36 induces its degradation. Importantly, inhibition of MEL1 degradation either by XBOS36 knockdown or by MEL1 overexpression prevents the formation of pollen at the microspore stage. Further mechanistic analysis showed that disrupting MEL1 homeostasis in germ cells leads to off-target cleavage of phasiRNA target genes. Our findings thus provide insight into the communication between a monocot-specific E3 ligase and an AGO protein during plant reproductive development.


Asunto(s)
Oryza/fisiología , Proteínas de Plantas/metabolismo , Esporas/crecimiento & desarrollo , Ubiquitina/metabolismo , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Regulación de la Expresión Génica de las Plantas , Lisina/metabolismo , Meiosis , Oryza/genética , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Polen/genética , Polen/crecimiento & desarrollo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , ARN de Planta/genética , ARN de Planta/metabolismo , ARN Pequeño no Traducido/genética , ARN Pequeño no Traducido/metabolismo , Esporas/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
8.
J Magn Reson Imaging ; 59(2): 535-545, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37191039

RESUMEN

BACKGROUND: Indicators for assessing myocardial viability and risk stratification in patients with coronary chronic total occlusion (CTO) are still in the research stage. PURPOSE: To use stress-MRI to assess myocardial function, blood perfusion, and viability and to explore their relationship with collateral circulation. STUDY TYPE: Prospective. SUBJECTS: Fifty-one patients with CTO in at least one major artery confirmed by X-ray coronary angiography (male: 46; age 55.2 ± 10.8 years). FIELD STRENGTH/SEQUENCE: 3.0T; TurboFlash, balanced steady-state free precession cine, and phase-sensitive inversion recovery sequences. ASSESSMENT: Stress-MRI was used to obtain qualitative and quantitative parameters of segmental myocardium. Myocardial segments supplied by CTO target vessels were grouped according to the degree of collateral circulation assessed by radiographic coronary angiography (no/mild, moderate, or good). Depending on qualitative stress perfusion assessment and late gadolinium enhancement (LGE) extent, segments were also categorized as negative, viable, or trans-infarcted. STATISTICAL TESTS: Independent sample Student's t-test, one-way analysis of variance (ANOVA) test, Mann-Whitney U test, Kruskal-Wallis test, Spearman correlation coefficient (r). P < 0.05 was considered statistically significant. RESULTS: A total of 334 segments were supplied by CTO target vessels. The radial strain (RS), circumferential strain (CS), longitudinal strain (LS) of the negative, viable, and trans-infarcted regions showed a significant and stepwise impairment. Myocardial blood flow at rest was positively correlated with RS, CS, and LS (r = 0.42, 0.43, 0.38, respectively). Among the different collateral circulation, there were no significant differences in RS, CS, LS, and LGE volume (P = 0.788, 0.562, 0.122, 0.170, respectively), and there were also no statistically significant differences in the proportions of negative, viable, and trans-infarcted regions (P = 0.372). DATA CONCLUSION: Myocardial perfusion obtained by stress-MRI combined with strain and LGE may comprehensively evaluate myocardial function and viability, and has potential to facilitate risk stratification of CTO. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.


Asunto(s)
Oclusión Coronaria , Intervención Coronaria Percutánea , Humanos , Masculino , Adulto , Persona de Mediana Edad , Anciano , Medios de Contraste , Oclusión Coronaria/diagnóstico por imagen , Estudios Prospectivos , Gadolinio , Miocardio , Imagen por Resonancia Magnética , Medición de Riesgo , Imagen por Resonancia Cinemagnética
9.
J Magn Reson Imaging ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38721820

RESUMEN

BACKGROUND: The angiographic features of moyamoya disease (MMD) and atherosclerosis-associated moyamoya vasculopathy (AS-MMV) are similar, but the etiology and clinical treatment strategies are different. Differentiating MMD from AS-MMV helps to choose the appropriate treatment. PURPOSE: To investigate the feasibility of a nomogram based on high-resolution vessel wall (HR-VWI) MRI features to differentiate MMD from AS-MMV. STUDY TYPE: Retrospective. SUBJECTS: One hundred and two patients with MMD (N = 52) or AS-MMV (N = 50) in the training cohort (9-72 years; 54 females) and 70 patients with MMD (N = 42) or AS-MMV (N = 28) in the validation cohort (7-69 years; 33 females). FIELD STRENGTH/SEQUENCE: 3-T, three-dimensional time-of-flight MR angiography (3D-TOF-MRA), spin echo high-resolution 3D T1-weighted imaging (3D-T1WI), 3D T2-weighted imaging (3D-T2WI), and contrast-enhanced 3D-T1WI. ASSESSMENT: Image assessment was performed by three neuroradiologists (with 10, 15, and 18 years of experience). Demographic characteristic and image features were evaluated and compared. Independent factors of MMD were screened to construct a nomogram model in the training cohort. The validation cohort was used to validated its generality. STATISTICAL TESTS: Interclass correlation coefficient (ICC), kappa, t-test, χ2 test, receiver operating characteristic (ROC) curve, area under the curve (AUC), calibration curve and concordance index (C-index). A P-value <0.05 was considered statistically significant. RESULTS: Significant differences were observed between MMD and AS-MMV in terms of age, vessel outer diameter, vessel wall thickening pattern, maximum thickness, dot sign, and anterior cerebral artery (ACA) involved. Age, outer diameter, dot sign, and ACA involved were independent factors. The C-index was 0.886 in the training cohort and 0.859 in the validation cohort. The ROC demonstrated high diagnostic efficacy with an AUC of 0.884 in the training cohort and 0.857 in the validation cohort. DATA CONCLUSION: A nomogram model based on age, vessel outer diameter, dot sign and ACA involved may effectively distinguish MMD from AS-MMV with good reliability and accuracy. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.

10.
Plant Biotechnol J ; 21(6): 1286-1300, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36952539

RESUMEN

Brown planthopper (BPH, Nilaparvata lugens), a highly destructive insect pest, poses a serious threat to rice (Oryza sativa) production worldwide. Jasmonates are key phytohormones that regulate plant defences against BPH; however, the molecular link between jasmonates and BPH responses in rice remains largely unknown. Here, we discovered a Poaceae-specific metabolite, mixed-linkage ß-1,3;1,4-d-glucan (MLG), which contributes to jasmonate-mediated BPH resistance. MLG levels in rice significantly increased upon BPH attack. Overexpressing OsCslF6, which encodes a glucan synthase that catalyses MLG biosynthesis, significantly enhanced BPH resistance and cell wall thickness in vascular bundles, whereas knockout of OsCslF6 reduced BPH resistance and vascular wall thickness. OsMYC2, a master transcription factor of jasmonate signalling, directly controlled the upregulation of OsCslF6 in response to BPH feeding. The AT-rich domain of the OsCslF6 promoter varies in rice varieties from different locations and natural variants in this domain were associated with BPH resistance. MLG-derived oligosaccharides bound to the plasma membrane-anchored LECTIN RECEPTOR KINASE1 OsLecRK1 and modulated its activity. Thus, our findings suggest that the OsMYC2-OsCslF6 module regulates pest resistance by modulating MLG production to enhance vascular wall thickness and OsLecRK1-mediated defence signalling during rice-BPH interactions.


Asunto(s)
Hemípteros , Oryza , Animales , Glucanos/metabolismo , Oryza/genética , Oryza/metabolismo , Poaceae
11.
New Phytol ; 237(6): 2238-2254, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36513604

RESUMEN

Submergence is an abiotic stress that limits agricultural production world-wide. Plants sense oxygen levels during submergence and postsubmergence reoxygenation and modulate their responses. Increasing evidence suggests that completely submerged plants are often exposed to low-light stress, owing to the depth and turbidity of the surrounding water; however, how light availability affects submergence tolerance remains largely unknown. Here, we showed that Arabidopsis thaliana MYB DOMAIN PROTEIN30 (MYB30) is an important transcription factor that integrates light signaling and postsubmergence stress responses. MYB DOMAIN PROTEIN30 protein abundance decreased upon submergence and accumulated during reoxygenation. Under submergence conditions, CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1), a central regulator of light signaling, caused the ubiquitination and degradation of MYB30. In response to desubmergence, however, light-induced MYB30 interacted with MYC2, a master transcription factor involved in jasmonate signaling, and activated the expression of the VITAMIN C DEFECTIVE1 (VTC1) and GLUTATHIONE SYNTHETASE1 (GSH1) gene families to enhance antioxidant biosynthesis. Consistent with this, the myb30 knockout mutant showed increased sensitivity to submergence, which was partially rescued by overexpression of VTC1 or GSH1. Thus, our findings uncover the mechanism by which the COP1-MYB30 module integrates light signals with cellular oxidative homeostasis to coordinate plant responses to postsubmergence stress.


Asunto(s)
Arabidopsis , Estrés Fisiológico , Factores de Transcripción , Antioxidantes/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ácido Ascórbico , Regulación de la Expresión Génica de las Plantas , Glutamato-Cisteína Ligasa/genética , Glutamato-Cisteína Ligasa/metabolismo , Glutatión/metabolismo , Fenómenos Fisiológicos de las Plantas , Estrés Fisiológico/genética , Estrés Fisiológico/fisiología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
12.
Plant Cell ; 32(10): 3290-3310, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32753431

RESUMEN

In plants, the ubiquitin-proteasome system, endosomal sorting, and autophagy are essential for protein degradation; however, their interplay remains poorly understood. Here, we show that four Arabidopsis (Arabidopsis thaliana) E3 ubiquitin ligases, SEVEN IN ABSENTIA OF ARABIDOPSIS THALIANA1 (SINAT1), SINAT2, SINAT3, and SINAT4, regulate the stabilities of FYVE DOMAIN PROTEIN REQUIRED FOR ENDOSOMAL SORTING1 (FREE1) and VACUOLAR PROTEIN SORTING23A (VPS23A), key components of the endosomal sorting complex required for transport-I, to modulate abscisic acid (ABA) signaling. GFP-SINAT1, GFP-SINAT2, and GFP-SINAT4 primarily localized to the endosomal and autophagic vesicles. SINATs controlled FREE1 and VPS23A ubiquitination and proteasomal degradation. SINAT overexpressors showed increased ABA sensitivity, ABA-responsive gene expression, and PYRABACTIN RESISTANCE1-LIKE4 protein levels. Furthermore, the SINAT-FREE1/VPS23A proteins were codegraded by the vacuolar pathway. In particular, during recovery post-ABA exposure, SINATs formed homo- and hetero-oligomers in vivo, which were disrupted by the autophagy machinery. Taken together, our findings reveal a novel mechanism by which the proteasomal and vacuolar turnover systems regulate ABA signaling in plants.


Asunto(s)
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Ácido Abscísico/farmacología , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Autofagia , Regulación de la Expresión Génica de las Plantas , Espectrometría de Masas/métodos , Plantas Modificadas Genéticamente , Mapas de Interacción de Proteínas/fisiología , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Vacuolas/metabolismo , Proteínas de Transporte Vesicular/genética
13.
J Recept Signal Transduct Res ; 43(2): 62-71, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37330920

RESUMEN

Oxidative stress, inflammation and apoptosis are important pathogenic factors of diabetic retinopathy (DR). In the current study, we aimed to evaluate the potential role of Rhein, a natural anthraquinone compound found in rhubarb, in high glucose (HG)-induced Müller cells (MIO-M1). Cell Counting Kit­8 assay, TUNEL assay, Western blot analysis, Reverse transcription quantitative polymerase chain reaction (RT-qPCR), and ELISA were conducted to assess the effects of Rhein on Müller cells. Additionally, the EX-527, an Sirt1 inhibitor, was used to study whether the effects of Rhein, on HG-induced Müller cells were mediated by activation of the Sirt1 signaling pathway. Our data showed that Rhein improved cell viability of HG-induced Müller cells. Rhein reduced the ROS and MDA production and increased the activities of SOD and CAT in Müller cells in response to HG stimulation. Rhein decreased the production of VEGF, IL-1ß, IL-6 and TNF-α. Moreover, Rhein attenuated HG-induced apoptosis, evidenced by increase in Bcl-2 level and decreases in the Bax, caspase-3 expression. It was also found that EX-527 counteracted Rhein-mediated anti-inflammatory, antioxidant and anti-apoptosis effects on Müller cells. The protein levels of p-AMPK and PGC-1α were also upregulated by Rhein. In conclusion, these findings support that Rhein may ameliorate HG-induced inflammation, oxidative stress, apoptosis and protect against mitochondrial dysfunction by the activation of the AMPK/Sirt1/PGC-1α signaling pathway.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Células Ependimogliales , Humanos , Células Ependimogliales/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Sirtuina 1/genética , Sirtuina 1/metabolismo , Estrés Oxidativo , Antraquinonas/farmacología , Glucosa/toxicidad , Glucosa/metabolismo , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/genética
14.
J Magn Reson Imaging ; 57(4): 1071-1078, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35932167

RESUMEN

BACKGROUND: Stiffness of meningioma is an important factor affecting the surgical resection and the prognosis of patients. PURPOSE: To examine the feasibility of APTw-magnetic resonance imaging (MRI) in evaluating meningioma stiffness. STUDY TYPE: Retrospective. POPULATION: Seventy-one patient with meningiomas, 39 were male and 32 were female; the mean age was 51 ± 10 years. FIELD STRENGTH/SEQUENCE: 3.0T; Turbo-spin-echo T1 -weighted and Gd-T1 -weighted sequence; Turbo-spin-echo T2 -weighted sequence; 2D fat-suppressed, turbo-spin-echo APTw pulse sequence. ASSESSMENT: The T1 WI signal intensity score, T2 WI signal intensity score, APTwmin , APTwmax , and APTwmean values were compared between soft, medium stiff and stiff meningiomas or non-stiff meningiomas and stiff meningiomas group. STATISTICAL TESTS: Chi-square test, one-way ANOVA analysis, independent-samples t-test, intra-class correlation coefficient, rank-sum test, receiver operating characteristic curve analysis. P < 0.05 was considered statistically significant in all tests. RESULTS: APTwmin and APTwmean in the stiff group were significantly lower than that in the non-stiff group (2.79% ± 0.42% vs. 1.90% ± 0.60% and 3.20% ± 0.31% vs. 2.55% ± 0.61%). APTwmin and APTwmean in the stiff group were significantly lower than that in the medium stiff and soft groups (1.90% ± 0.60% vs. 2.69% ± 0.40% and 3.12% ± 0.32%, 2.55% ± 0.61% vs. 3.17% ± 0.33% and 3.39% ± 0.18%), APTwmin in the medium stiff group was significantly lower than in the soft group, there was no significant difference in APTwmean between the medium stiff and soft groups (P = 0.190). APTwmin showed the best diagnostic performance for evaluating meningioma stiffness with an area under the curve of 0.913, when the APTwmin was lower than 2.4%, the meningioma was defined as a stiff tumor, the sensitivity, specificity, and accuracy were 87.1%, 87.5%, and 85.9%, respectively. DATA CONCLUSION: APTw-MRI could be used to evaluate meningioma stiffness, with APTwmin having the best evaluative efficiency. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 1.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Meningioma/patología , Protones , Estudios de Factibilidad , Amidas , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos
15.
Acta Radiol ; 64(3): 951-961, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35765225

RESUMEN

BACKGROUND: Non-invasive imaging technologies for assessing axillary lymph node (ALN) metastasis of breast cancer are needed in clinical practice. PURPOSE: To explore the clinical value of intravoxel incoherent motion (IVIM) and diffusional kurtosis imaging (DKI) for predicting ALN metastasis of breast cancer. MATERIAL AND METHODS: A total of 194 patients with pathologically confirmed breast cancer who underwent IVIM and DKI examination were reviewed retrospectively. The IVIM derived parameters of D, D*, and f and DKI-derived parameters of MD and MK were measured. The independent samples t-test was used to compare the parameters between the ALN metastasis and non-ALN metastasis groups. Receiver operating characteristic (ROC) curve analysis was also performed. RESULTS: The D and MD in the ALN metastasis group were significantly lower than those in the non-ALN metastasis group (P < 0.001, P < 0.001). The D*, f, and MK were higher in the ALN metastasis group than in the non-ALN metastasis group (P = 0.015, P = 0.014, and P = 0.001, respectively). The area under the ROC curve (AUC) of D (0.768) was highest. In addition, the diagnostic efficiency of both IVIM and DKI were higher than that of the conventional MRI (P = 0.002, P = 0.048). The diagnostic efficiency of IVIM + DKI were higher than that of the IVIM or DKI alone (P = 0.021, P = 0.004). CONCLUSION: IVIM and DKI can be used for predicting breast cancer ALN metastasis with D as the most meaningful parameter.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Estudios Retrospectivos , Neoplasias de la Mama/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Metástasis Linfática/diagnóstico por imagen , Movimiento (Física) , Ganglios Linfáticos/diagnóstico por imagen
16.
Proc Natl Acad Sci U S A ; 117(1): 727-732, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31871204

RESUMEN

The intine, the inner layer of the pollen wall, is essential for the normal development and germination of pollen. However, the composition and developmental regulation of the intine in rice (Oryza sativa) remain largely unknown. Here, we identify a microRNA, OsmiR528, which regulates the formation of the pollen intine and thus male fertility in rice. The mir528 knockout mutant aborted pollen development at the late binucleate pollen stage, significantly decreasing the seed-setting rate. We further demonstrated that OsmiR528 affects pollen development by directly targeting the uclacyanin gene OsUCL23 (encoding a member of the plant-specific blue copper protein family of phytocyanins) and regulating intine deposition. OsUCL23 overexpression phenocopied the mir528 mutant. The OsUCL23 protein localized in the prevacuolar compartments (PVCs) and multivesicular bodies (MVBs). We further revealed that OsUCL23 interacts with a member of the proton-dependent oligopeptide transport (POT) family of transporters to regulate various metabolic components, especially flavonoids. We propose a model in which OsmiR528 regulates pollen intine formation by directly targeting OsUCL23 and in which OsUCL23 interacts with the POT protein on the PVCs and MVBs to regulate the production of metabolites during pollen development. The study thus reveals the functions of OsmiR528 and an uclacyanin during pollen development.


Asunto(s)
Metaloproteínas/genética , MicroARNs/metabolismo , Oryza/fisiología , Proteínas de Plantas/genética , Polen/metabolismo , Regulación de la Expresión Génica de las Plantas , Microscopía Electrónica de Transmisión , Plantas Modificadas Genéticamente , Polen/ultraestructura
17.
Eur Radiol ; 32(2): 761-770, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34482428

RESUMEN

OBJECTIVE: To develop and validate deep learning (DL) methods for diagnosing autism spectrum disorder (ASD) based on conventional MRI (cMRI) and apparent diffusion coefficient (ADC) images. METHODS: A total of 151 ASD children and 151 age-matched typically developing (TD) controls were included in this study. The data from these subjects were assigned to training and validation datasets. An additional 20 ASD children and 25 TD controls were acquired, whose data were utilized in an independent test set. All subjects underwent cMRI and diffusion-weighted imaging examination of the brain. We developed a series of DL models to separate ASD from TD based on the cMRI and ADC data. The seven models used include five single-sequence models (SSMs), one dominant-sequence model (DSM), and one all-sequence model (ASM). To enhance the feature detection of the models, we embed an attention mechanism module. RESULTS: The highest AUC (0.824 ~ 0.850) was achieved when applying the SSM based on either FLAIR or ADC to the validation and independent test sets. A DSM using the combination of FLAIR and ADC showed an improved AUC in the validation (0.873) and independent test sets (0.876). The ASM also showed better diagnostic value in the validation (AUC = 0.838) and independent test sets (AUC = 0.836) compared to the SSMs. Among the models with attention mechanism, the DSM achieved the highest diagnostic performance with an AUC, accuracy, sensitivity, and specificity of 0.898, 84.4%, 85.0%, and 84.0% respectively. CONCLUSIONS: This study established the potential of DL models to distinguish ASD cases from TD controls based on cMRI and ADC images. KEY POINTS: • Deep learning models based on conventional MRI and ADC can be used to diagnose ASD. • The model (DSM) based on the FLAIR and ADC sequence achieved the best diagnostic performance with an AUC of 0.836 in the independent test sets. • The attention mechanism further improved the diagnostic performance of the models.


Asunto(s)
Trastorno del Espectro Autista , Aprendizaje Profundo , Algoritmos , Trastorno del Espectro Autista/diagnóstico por imagen , Niño , Imagen de Difusión por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética
18.
PLoS Genet ; 15(5): e1008120, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31116744

RESUMEN

N6-Methyladenosine (m6A) RNA methylation plays important roles during development in different species. However, knowledge of m6A RNA methylation in monocots remains limited. In this study, we reported that OsFIP and OsMTA2 are the components of m6A RNA methyltransferase complex in rice and uncovered a previously unknown function of m6A RNA methylation in regulation of plant sporogenesis. Importantly, OsFIP is essential for rice male gametogenesis. Knocking out of OsFIP results in early degeneration of microspores at the vacuolated pollen stage and simultaneously causes abnormal meiosis in prophase I. We further analyzed the profile of rice m6A modification during sporogenesis in both WT and OsFIP loss-of-function plants, and identified a rice panicle specific m6A modification motif "UGWAMH". Interestingly, we found that OsFIP directly mediates the m6A methylation of a set of threonine protease and NTPase mRNAs and is essential for their expression and/or splicing, which in turn regulates the progress of sporogenesis. Our findings revealed for the first time that OsFIP plays an indispensable role in plant early sporogenesis. This study also provides evidence for the different functions of the m6A RNA methyltransferase complex between rice and Arabidopsis.


Asunto(s)
Gametogénesis en la Planta , Regulación de la Expresión Génica de las Plantas , Metiltransferasas/genética , Oryza/genética , Proteínas de Plantas/genética , Subunidades de Proteína/genética , Adenosina/análogos & derivados , Secuencias de Aminoácidos , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Mutación con Pérdida de Función , Profase Meiótica I , Metilación , Metiltransferasas/metabolismo , Nucleósido-Trifosfatasa/genética , Nucleósido-Trifosfatasa/metabolismo , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Polen/genética , Polen/crecimiento & desarrollo , Polen/metabolismo , Subunidades de Proteína/metabolismo , ARN de Planta , Especificidad de la Especie
19.
Eur Arch Otorhinolaryngol ; 279(2): 695-702, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33687508

RESUMEN

PURPOSE: To characterize the auditory and imaging markers of atypical enlarged vestibular aqueduct (EVA). METHODS: 15 EVA cases (26 ears) confirmed via high-resolution MRI (HRMRI) that did not meet the Valvassori criterion on high-resolution CT (HRCT) were classified as atypical EVA. Another 21 EVA cases (40 ears) meeting the Valvassori criterion were randomly chosen as typical EVA. The hearing loss (HL), HRCT, and HRMRI findings were compared between the two groups. RESULTS: The difference of HL severity between atypical and typical EVA was not statistically significant (χ2 = 0.12, P > 0.05. The vestibular aqueducts (VA) of atypical EVA cases manifested as borderline dilation (n = 17), focal dilation (n = 3), and normal appearance (n = 6) on the HRCT. The midpoint width of atypical and typical EVA cases was 1.06 ± 0.18 mm and 2.10 ± 0.55 mm, respectively, exhibiting a significant difference (t = - 9.20, P < 0.05). In the HRMRI, the degree of dilation and shape of the intraosseous partition of endolymphatic duct and sac (ES) was similar to that of VA on HRCT, while their extraosseous ES was depicted variable slighter dilation compared to that of typical one, the difference between them was statistically significant (t = - 4.10, P < 0.05). CONCLUSION: The HL severity of atypical EVA ears was similar to that of typical ones. Nevertheless, borderline, focal dilation and normal-like appearance of VAs on HRCT and variablely slighter dilation of the extraosseous ES on HRMRI are its characteristic imaging findings.


Asunto(s)
Pérdida Auditiva Sensorineural , Acueducto Vestibular , Conducto Endolinfático , Humanos , Estudios Retrospectivos , Acueducto Vestibular/anomalías , Acueducto Vestibular/diagnóstico por imagen
20.
Plant Physiol ; 182(1): 204-214, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31694901

RESUMEN

MicroRNAs (miRNAs) are small noncoding RNAs of ∼21 nt in length, which have regulatory roles in many biological processes. In animals, proper functioning of the circadian clock, which is closely linked to the fitness of almost all living organisms, is regulated by miRNAs. However, to date, there have been no reports of the roles of miRNA in regulation of the plant circadian rhythm. Here, we report a natural variant of miR397 that lengthens the circadian period and controls flowering time in Arabidopsis (Arabidopsis thaliana). Highly conserved among angiosperms, the miRNA miR397 has two members in Arabidopsis: miR397a and miR397b. However, only miR397b significantly delayed flowering. Our results suggest that miR397b controls flowering by targeting CASEIN KINASE II SUBUNIT BETA3 (CKB3), in turn modulating the circadian period of CIRCADIAN CLOCK ASSOCIATED1 (CCA1). We further demonstrated that CCA1 directly bound to the promoter of MIR397B and suppressed its expression, forming a miR397b-CKB3-CCA1 circadian regulation feedback circuit. Evolutionary analysis revealed that miR397b is a newly evolved genetic variant in Arabidopsis, and the miR397b targeting mode may have a role in enhancing plant fitness. Our results provide evidence for miRNA-mediated circadian regulation in plants and suggest the existence of a feedback loop to manipulate plant flowering through the regulation of circadian rhythm.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Arabidopsis/fisiología , Ritmo Circadiano/fisiología , MicroARNs/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Ritmo Circadiano/genética , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , MicroARNs/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
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