Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
Plant Cell ; 31(11): 2751-2767, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31530734

RESUMEN

Carotenoids are a group of natural tetraterpenoid pigments with indispensable roles in the plant life cycle and the human diet. Although the carotenoid biosynthetic pathway has been well characterized, the regulatory mechanisms that control carotenoid metabolism, especially in floral organs, remain poorly understood. In this study, we identified an anthocyanin-related R2R3-MYB protein, WHITE PETAL1 (WP1), that plays a critical role in regulating floral carotenoid pigmentation in Medicago truncatula Carotenoid analyses showed that the yellow petals of the wild-type M. truncatula contained high concentrations of carotenoids that largely consisted of esterified lutein and that disruption of WP1 function via Tnt1 insertion led to substantially reduced lutein accumulation. WP1 mainly functions as a transcriptional activator and directly regulates the expression of carotenoid biosynthetic genes including MtLYCe and MtLYCb through its C-terminal acidic activation motif. Further molecular and genetic analyses revealed that WP1 physically interacts with MtTT8 and MtWD40-1 proteins and that this interaction facilitates WP1's function in the transcriptional activation of both carotenoid and anthocyanin biosynthetic genes. Our findings demonstrate the molecular mechanism of WP1-mediated regulation of floral carotenoid pigmentation and suggest that the conserved MYB-basic-helix-loop-helix-WD40 regulatory module functions in carotenoid biosynthesis in M. truncatula, with specificity imposed by the MYB partner.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Flores/metabolismo , Medicago truncatula/metabolismo , Pigmentación/fisiología , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Antocianinas/metabolismo , Proteínas de Arabidopsis , Secuencia de Bases , Vías Biosintéticas , Carotenoides/metabolismo , Flores/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Medicago truncatula/genética , Fenotipo , Pigmentación/genética , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Factores de Transcripción/genética
2.
New Phytol ; 229(6): 3330-3344, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33222243

RESUMEN

Patterned leaf coloration in plants generates remarkable diversity in nature, but the underlying mechanisms remain largely unclear. Here, using Medicago truncatula leaf marking as a model, we show that the classic M. truncatula leaf anthocyanin spot trait depends on two R2R3 MYB paralogous regulators, RED HEART1 (RH1) and RH2. RH1 mainly functions as an anthocyanin biosynthesis activator that specifically determines leaf marking formation depending on its C-terminal activation motif. RH1 physically interacts with the M. truncatula bHLH protein MtTT8 and the WDR family member MtWD40-1, and this interaction facilitates RH1 function in leaf anthocyanin marking formation. RH2 has lost transcriptional activation activity, due to a divergent C-terminal domain, but retains the ability to interact with the same partners, MtTT8 and MtWD40-1, as RH1, thereby acting as a competitor in the regulatory complex and exerting opposite effects. Moreover, our results demonstrate that RH1 can activate its own expression and that RH2-mediated competition can repress RH1 expression. Our findings reveal the molecular mechanism of the antagonistic gene paralogs RH1 and RH2 in determining anthocyanin leaf markings in M. truncatula, providing a multidimensional paralogous-antagonistic regulatory paradigm for fine-tuning patterned pigmentation.


Asunto(s)
Medicago truncatula , Antocianinas , Regulación de la Expresión Génica de las Plantas , Medicago truncatula/genética , Medicago truncatula/metabolismo , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
3.
BMC Cardiovasc Disord ; 21(1): 457, 2021 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-34548009

RESUMEN

BACKGROUND: Spinal artery ischemia (SCI) events can result from over coverage of the descending thoracic aorta with a coated stent during Thoracic Endovascular Aortic Repair (TEVAR). The aim of this study was to determine whether a new distal perforating stent could reduce the incidence of spinal cord ischemia while remodeling the true lumen. METHODS: TBAD patients treated with Talos stent in the vascular surgery Department of Yan 'an Hospital affiliated to Kunming Medical University between December 2017 and October 2019 were retrospectively analyzed to investigate the short-term safety and effectiveness of Talos stent. RESULTS: A total of the 20 patients, including 14 males and 6 females, with an average age of 52.65 ± 8.98 years (range 37-68 years), were included in the analysis. Stent-grafts were successfully implanted in all patients under local anesthesia, with a technical success rate of 100%. The average operation time was 50.75 ± 13.01 min. A total of 2 cases (10%) presented chest pain associated with intercostal artery ischemia that was relieved on the 3rd and 5th postoperative day, respectively. Postoperative mean follow-up was 16.15 ± 3.99 months. No paraplegia or other complications occurred. And stenting did not induce new tears. No migration, deformation, or fracture of the stents occurred. There was a significant difference in the remolding of the true lumen preoperatively and at 12 months postoperatively (P < 0.05). CONCLUSIONS: Talos stent has achieved satisfactory clinical treatment results in short term.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Disección Aórtica/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Isquemia de la Médula Espinal/prevención & control , Stents , Adulto , Anciano , Disección Aórtica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Implantación de Prótesis Vascular/efectos adversos , China , Procedimientos Endovasculares/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Paraplejía/etiología , Paraplejía/prevención & control , Diseño de Prótesis , Estudios Retrospectivos , Isquemia de la Médula Espinal/etiología , Factores de Tiempo , Resultado del Tratamiento
4.
Front Neurorobot ; 17: 1250706, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37663762

RESUMEN

Recognizing occluded facial expressions in the wild poses a significant challenge. However, most previous approaches rely solely on either global or local feature-based methods, leading to the loss of relevant expression features. To address these issues, a feature fusion residual attention network (FFRA-Net) is proposed. FFRA-Net consists of a multi-scale module, a local attention module, and a feature fusion module. The multi-scale module divides the intermediate feature map into several sub-feature maps in an equal manner along the channel dimension. Then, a convolution operation is applied to each of these feature maps to obtain diverse global features. The local attention module divides the intermediate feature map into several sub-feature maps along the spatial dimension. Subsequently, a convolution operation is applied to each of these feature maps, resulting in the extraction of local key features through the attention mechanism. The feature fusion module plays a crucial role in integrating global and local expression features while also establishing residual links between inputs and outputs to compensate for the loss of fine-grained features. Last, two occlusion expression datasets (FM_RAF-DB and SG_RAF-DB) were constructed based on the RAF-DB dataset. Extensive experiments demonstrate that the proposed FFRA-Net achieves excellent results on four datasets: FM_RAF-DB, SG_RAF-DB, RAF-DB, and FERPLUS, with accuracies of 77.87%, 79.50%, 88.66%, and 88.97%, respectively. Thus, the approach presented in this paper demonstrates strong applicability in the context of occluded facial expression recognition (FER).

5.
Front Genet ; 13: 1054567, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36685832

RESUMEN

Background: The GAP Activity Towards Rags 1 (GATOR1) complex, which includes DEPDC5, NPRL2, and NPRL3, plays a key role in epilepsy. It has been reported that focal epilepsy is associated with mutations in the NPRL3 gene in some cases. We report two rare mutations in the NPRL3 gene in two unrelated Chinese families with focal epilepsy in this study. Methods: The proband and her brother in family E1 first experienced seizures at 1.5 and 6 years of age, respectively. Despite resection of epileptogenic foci, she still suffered recurrent seizures. The first seizure of a 20-year-old male proband in family E2 occurred when he was 2 years old. To identify pathogenic variants in these families, whole-exome sequencing (WES) was performed on genomic DNA from peripheral blood. Results: In family E1, the trio-WES analysis of the proband and her brother without apparent structural brain abnormalities identified a heterozygous variant in the NPRL3 gene (c.954C>A, p.Y318*, NM_001077350.3). In family E2, the proband carried a heterozygous NPRL3 mutation (c.1545-1G>C, NM_001077350.3). Surprisingly, the mothers of the two probands each carried the variants, but neither had an attack. Bioinformatics analysis predicted that the mutation (c.954C>A) was in the highly conserved amino acid residues of NPRL3, which affected the α-helix of NPRL3 protein, leading to a truncated protein. The splice variant (c.1545-1G>C) resulted in the loss of the last exon of the NPRL3 gene. Conclusion: The results of this study provide a foundation for diagnosing NPRL3-related epilepsy by enriching their genotypes and phenotypes and help us identify the genetic etiologies of epilepsy in these two families.

6.
Chem Commun (Camb) ; 58(60): 8428-8431, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35796312

RESUMEN

A serial oxygen vacancy (OV) on Nb2O5 is synthesised by H2 calcination, and H-300 exhibited high selectivity and activity for H2O2 (93.4%, 562.5 mmol gcat-1). A volcano relationship is identified between the OV content and performance, which provides an attractive insight into designing electrocatalysts.

7.
J Plant Physiol ; 256: 153308, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33190018

RESUMEN

Cytokinin oxidase/dehydrogenases (CKXs) play a key role in the irreversible degradation of phytohormone cytokinin that is necessary for various plant growth and development processes. However, thus far, detailed investigations of the CKX gene family in the model legume Medicago truncatula are limited. In this study, we identified 9 putative CKX homologues with conserved FAD- and cytokinin-binding domains in the M. truncatula genome. We analyzed their phylogenetic relationship, gene structure, conserved domain, expression pattern, protein subcellular locations and other properties. The tissue-specific expression profiles of the MtCKX genes are different among different members and these MtCKXs also displayed different patterns in response to synthetic cytokinin 6-benzylaminopurine (6-BA) and indole-3-acetic acid (IAA), suggesting their diverse roles in M. truncatula development. To further understand the biological function of MtCKXs, we identified and characterized mutants of each MtCKX by taking advantage of the Tnt1 mutant population in M. truncatula. Results indicated that M. truncatula plants harboring Tnt1 insertions in each single MtCKX genes showed no morphological changes in aerial parts, suggesting functional redundancy of MtCKXs in M. truncatula shoot development. However, disruption of Medtr4g126160, which is predominantly expressed in roots, leads to an obvious reduced primary root length and increased lateral root number, indicating the specific roles of cytokinin in regulating root architecture. We systematically analyzed the MtCKX gene family at the genome-wide level and revealed their possible roles in M. truncatula shoot and root development, which shed lights on understanding the biological function of CKX family genes in related legume plants.


Asunto(s)
Citocininas/genética , Citocininas/metabolismo , Genes de Plantas , Medicago truncatula/genética , Medicago truncatula/metabolismo , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Regulación de la Expresión Génica de las Plantas , Estudio de Asociación del Genoma Completo , Filogenia
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA