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1.
Food Res Int ; 187: 114417, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763667

RESUMO

Resistant starch serves as a prebiotic in the large intestine, aiding in the maintenance of a healthy intestinal environment and mitigating associated chronic illnesses. This study aimed to investigate the impact of resistant starch-enriched brown rice (RBR) on intestinal health and functionality. We assessed changes in resistant starch concentration, structural alterations, and branch chain length distribution throughout the digestion process using an in vitro model. The efficacy of RBR in the intestinal environment was evaluated through analyses of its prebiotic potential, effects on intestinal microbiota, and intestinal function-related proteins in obese animals fed a high-fat diet. RBR exhibited a higher yield of insoluble fraction in both the small and large intestines compared to white and brown rice. The total digestible starch content decreased, while the resistant starch content significantly increased during in vitro digestion. Furthermore, RBR notably enhanced the growth of four probiotic strains compared to white and brown rice, displaying higher proliferation activity than the positive control, FOS. Notably, consumption of RBR by high-fat diet-induced obese mice suppressed colon shortening, increased Bifidobacteria growth, and improved intestinal permeability. These findings underscore the potential prebiotic and gut health-promoting attributes of RBR, offering insights for the development of functional foods aimed at preventing gastrointestinal diseases.


Assuntos
Dieta Hiperlipídica , Microbioma Gastrointestinal , Camundongos Endogâmicos C57BL , Obesidade , Oryza , Prebióticos , Amido , Animais , Oryza/química , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos , Amido/metabolismo , Masculino , Obesidade/metabolismo , Camundongos Obesos , Amido Resistente , Probióticos , Digestão , Bifidobacterium/crescimento & desenvolvimento
2.
Food Res Int ; 170: 113011, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37316078

RESUMO

Dietary supplementation with indigestible carbohydrates is known to improve the gut environment and prevent obesity and inflammatory diseases by modulating the gut microbiota. In previous work, we established a method for the production of resistant starch (RS)-enriched high-amylose rice (R-HAR) using citric acid. The present study aimed to evaluate changes in structural characteristics during digestion of R-HAR and its effects on the gut health. A three-step in vitro digestion and fermentation model was used, then, RS content, scanning electron microscopy, and branch chain length distribution were analyzed during in vitro digestion. During the digestion of R-HAR, the RS content increased, and the structure was predicted to have a greater impact on the gut microbiota and gut environment. To study the intestinal health effects of R-HAR, its anti-inflammatory and gut barrier integrity activities were assayed in HFD-induced mice. Intake of R-HAR suppressed colonic shortening and inflammatory responses induced by HFD. Furthermore, R-HAR exhibited gut barrier protective activity with an increase in tight junction protein levels. We determined that R-HAR may be a potentially beneficial intestinal environment improver, which may have various implications in the food industry as rice.


Assuntos
Oryza , Animais , Camundongos , Camundongos Obesos , Amido Resistente , Amilose , Digestão
3.
Food Sci Biotechnol ; 32(2): 193-202, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36647528

RESUMO

The properties of wheat dough according to salt level and type of mixer were investigated, and parameters derived from each analysis were comprehensively compared. Mixolab analysis showed that water absorption decreased with salt level while the dough strength increased. In the Mixolab C2 stage, related with thermal strength, C2 temperature and time had stronger correlation with other dough strength parameters than C2 torque. Thickness increase of gluten strand was dominant in the doughs prepared by vertical mixer (VMD) than in those prepared by Mixolab device (MLD), for the same salt level. In large deformation, increase in resistance to extension by salt level was much greater in VMD than in MLD. In small deformation, relationships of salt level with G', G'' and power-law exponent (n) were linear and non-linear in MLD and VMD, respectively. Since MLD could not perfectly reflect VMD, properties of dough should be considered in multiple ways for its comprehensive understanding.

4.
Oncogene ; 41(50): 5373-5384, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36348010

RESUMO

Osteosarcoma, the most common pediatric bone tumor, is an aggressive heterogeneous malignancy defined by complex chromosomal aberrations. Overall survival rates remain at ~70%, but patients with chemoresistant or metastatic disease have extremely poor outcomes of <30%. A subgroup of tumors harbor amplification of chromosome 8q24.2 and increased expression of the oncogenic long noncoding RNA (lncRNA) Plasmacytoma Variant Translocation-1 (PVT-1), which is associated with an extremely poor clinical prognosis. This study demonstrates that PVT-1 is critical for osteosarcoma tumor-initiation potential. Chromatin Hybridization by RNA Purification analysis identified Tripartite-Motif Containing Family 28 (TRIM28) as a novel PVT-1 binding partner. Mechanistically, co-immunoprecipitation studies showed the PVT-1/TRIM28 complex binds and increases SUMOylation of phosphatidylinositol 3-kinase catalytic subunit type 3 (Vps34), which leads to enhanced ubiquitination and degradation of tumor suppressor complex 2 (TSC2), thus contributing to increased self-renewal and stem cell phenotypes. Furthermore, we identified that osteosarcoma cells with increased PVT-1 have enhanced sensitivity to the SUMOylation inhibitor, TAK-981. Altogether, this study elucidated a role for PVT-1 in the enhancement of cancer stem-like behaviors, including migration and invasion, in osteosarcoma, and identified the novel PVT-1/TRIM28 axis signaling cascade as a potential therapeutic target for osteosarcoma treatment.


Assuntos
Neoplasias Ósseas , Osteossarcoma , RNA Longo não Codificante , Proteína 28 com Motivo Tripartido , Proteína 2 do Complexo Esclerose Tuberosa , Humanos , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Osteossarcoma/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transdução de Sinais/genética , Proteína 28 com Motivo Tripartido/genética , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo
5.
Am J Health Behav ; 46(3): 315-323, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35794761

RESUMO

Objectives: Leisure engagement has been considered as a salient stress-coping strategy. However, during the COVID-19 pandemic, people's leisure engagement has been restricted due to COVID-19- related regulations and policies. Moreover, many Asian immigrants, including Korean immigrants in the US, have been exposed to additional challenges (e.g., discrimination and harassment), which negatively affected their leisure experiences. Methods: in this study, we categorized participants into 3 groups based on their leisure satisfaction changes before and during the pandemic and compared the groups regarding COVID-19 risk perception, stress-coping, and life satisfaction. Results: The Maintained or Increased Group (MIG) scored significantly lower stress than the Highly Decreased group (HDG); the MIG scored significantly higher life satisfaction than both the Slightly Decreased Group (SDG) and the HDG. Conclusion: The research demonstrated the importance of satisfactory leisure experience to cope with stress and be satisfied with their life in a stressful life event.


Assuntos
COVID-19 , Satisfação Pessoal , Adaptação Psicológica , Humanos , Atividades de Lazer , Pandemias , Estresse Psicológico
6.
J Food Sci ; 87(3): 1058-1068, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35122245

RESUMO

The effects of immersion time on the physicochemical properties and resistant starch (RS) formation of malic acid-treated rice were investigated. Malic acid treatment decreased the frequency of cracks within the rice kernel. The color (lightness) was significantly affected by the immersion time, reflecting the browning of rice. The degree of substitution gradually increased with the immersion time and reached a plateau after 12 h, and the intensity of the C=O bond peak detected in the Fourier-transform infrared spectroscopy showed a similar trend. However, the crystallinity of rice decreased as the immersion time increased, which was confirmed by the X-ray diffraction and thermal transition properties. A gradual increase in RS was observed as the immersion time and DS increased, ranging from 44.5% to 73.3%, reaching a maximum after 12 h of immersion. Therefore, 12 h was determined to be the optimal immersion time for maximizing RS content. This information about the structural characteristics and heat-stable properties of malic acid-treated rice in starch digestion can be used to develop a low-digestible food ingredient and lead to further application of the study. PRACTICAL APPLICATION: This study reported the preparation and physicochemical properties of malic acid-treated resistant starch with different immersion times. This information could contribute to the structural characterization of resistant starch and the development of low-calorie processed rice products.


Assuntos
Oryza , Imersão , Malatos , Oryza/química , Amido Resistente , Amido/química , Difração de Raios X
7.
Foods ; 10(10)2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34681470

RESUMO

Retrogradation is the principal cause for bread staling and, therefore, it has attracted a lot of interest from the food industry. In this study, the inhibitory effect of citrus peel hydrolysates (CPH) on retrogradation of wheat starch (WS) in the presence of sucrose was investigated. The pasting properties showed that further addition of CPH caused a lower setback value than the addition of sucrose alone. Hardness of the gel, retrograded at 4 °C for five days, showed a similar tendency, which was reduced more in CPH addition than WS itself or sucrose addition alone. The low retrogradation enthalpy of the CPH including starch gel also indicated the positive effect of CPH on retarding retrogradation. These results suggested that incorporation of CPH in starch-based foods would be effective for inhibiting retrogradation, preventing the deterioration of the quality of food products.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34360393

RESUMO

This study was conducted to investigate effects of a horticultural activity program based on a mediating variable model for improving vegetable preference among elementary students. A quasi-experimental design was employed with 136 students and 136 primary carers in Seoul, South Korea. Based on the mediation model for improving children's vegetable preference, 12 sessions were conducted, including gardening, nutrition education, and cooking activities using harvests. The program was conducted weekly for 12 weeks from March to July 2019. To investigate the effect of this program, mediating factors of the children were evaluated before and after the program. Pearson correlation analysis was used to identify the mediating factors. The nutrition index, attitude, knowledge, and eating habits of the primary carers were evaluated. Results showed children's nutrition and gardening knowledge, dietary self-efficacy, outcome expectancies, and vegetable preference were significantly improved (p < 0.001). Primary carers showed significant improvement in the nutrition index, knowledge, and attitude (p < 0.05). The correlation analysis confirmed that most of the mediating factors had significant correlations (p < 0.05). Therefore, administering a structured program involving horticultural activities and nutrition education as mediating factors for 12 sessions was effective in improving eating behavior for vegetables elementary school students and primary carers.


Assuntos
Instituições Acadêmicas , Verduras , Criança , Comportamento Alimentar , Frutas , Jardinagem , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Estudantes
9.
Ultrason Sonochem ; 76: 105650, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34182316

RESUMO

In this study, the effects of sonication and temperature-cycled storage on the structural properties and resistant starch content of high-amylose corn starch were investigated. Sonication induced a partial depolymerization of the molecular structures of amylopectin and amylose. Sonication treatment induced the appropriate structural changes for retrogradation. Although the relative crystallinity of sonicated starch was lower than that of non-sonicated starch, sonicated starch after retrogradation showed much higher relative crystallinity than non-sonicated starch. Regardless of sonication treatment, temperature-cycled storage resulted in a higher degree of retrogradation than isothermal storage, but the rate of retrogradation was greater in sonicated starch than in non-sonicated starch, as supported by retrogradation enthalpy, the Avrami constant, and relative crystallinity. The highly developed crystalline structure in sonicated starches due to retrogradation was reflected by the large amount of resistant starch.


Assuntos
Amilose/análise , Sonicação , Temperatura , Cinética
10.
Food Res Int ; 146: 110436, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34119249

RESUMO

This study aimed to further improve the previously described first-order equation representing in vitro digestion of starch by extensively explaining modified log of slope (LOS) plot method. Hydrolysis curves of various starches were analyzed using original and/or modified LOS plot methods. Some starches showed significant differences in the results from the two methods; specifically, the modified method better described the digestive behavior of starch with various digestion properties, supported by higher determination coefficient values and better estimation of the digestibility data over digestive phase. The digestion parameters obtained from the modified method provided multiple types of information, including amount and digestion rate of each starch fraction (rapidly digestible, slowly digestible, and resistant starch), supporting the concept of digestible fraction classification. Therefore, the modified LOS plot method described here can be applied as an effective tool for analyzing and describing the multi-scale in vitro digestion behavior of starch.


Assuntos
Digestão , Zea mays , Hidrólise , Amido
11.
Oncogene ; 40(6): 1176-1190, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33414491

RESUMO

Ewing sarcoma (ES) is the second most common bone tumor in children and young adults. Unfortunately, there have been minimal recent advancements in improving patient outcomes, especially in metastatic and recurrent diseases. In this study, we investigated the biological role of p21-activated kinases (PAKs) in ES, and the ability to therapeutically target them in high-risk disease. Via informatics analysis, we established the inverse association of PAK1 and PAK4 expression with clinical stage and outcome in ES patients. Through expression knockdown and small-molecule inhibition of PAKs, utilizing FRAX-597, KPT-9274, and PF-3758309 in multiple ES cell lines and patient-derived xenograft models, we further explored the role of PAKs in ES tumor growth and metastatic capabilities. In vitro studies in several ES cell lines indicated that diminishing PAK1 and PAK4 expression reduces tumor cell viability, migratory, and invasive properties. In vivo studies using PAK4 inhibitors, KPT-9274 and PF-3758309 demonstrated significant inhibition of primary and metastatic tumor formation, while transcriptomic analysis of PAK4-inhibitor-treated tumors identified concomitant suppression of Notch, ß-catenin, and hypoxia-mediated signatures. In addition, the analysis showed enrichment of anti-tumor immune regulatory mechanisms, including interferon (IFN)-É£ and IFN-α responses. Altogether, our molecular and pre-clinical studies are the first to establish a critical role for PAKs in ES development and progression, and consequently as viable therapeutic targets for the treatment of high-risk ES in the near future.


Assuntos
Sarcoma de Ewing/tratamento farmacológico , Quinases Ativadas por p21/genética , Acrilamidas/farmacologia , Aminopiridinas/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interferon-alfa/genética , Interferon gama/genética , Pirazóis/farmacologia , Pirróis/farmacologia , Sarcoma de Ewing/genética , Sarcoma de Ewing/patologia , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Quinases Ativadas por p21/antagonistas & inibidores
12.
Food Chem ; 318: 126490, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32146307

RESUMO

This study examined the contribution of amylose to the organization of each starch fraction in recrystallized starch. Amylosucrase (AS)-modified waxy potato starches with different branch chain lengths were completely solubilized with amylose (3:1 ratio) and recrystallized at 4 °C for 48 h. The content of rapidly digestible starch and resistant starch (RS) showed linear change with degree of AS modification, while slowly digestible starch (SDS) did not. The changes in structural characteristics were tracked according to serial removal of each fraction. Results from iodine binding property, branch chain length, X-ray diffraction, and thermal property analysis indicated that branch chain length of amylopectin determined the length of the amylose-amylopectin double helix and the mobility of amylose and that formation of SDS or RS could be induced by controlling the length of amylopectin chains. These findings could be used for production of customized starches with specific digestive properties for health benefits.


Assuntos
Amilopectina/química , Amilose/química , Glucosiltransferases/química , Solanum tuberosum/química , Amido/química , Cristalização , Digestão , Estrutura Molecular , Difração de Raios X
13.
Plant Mol Biol ; 103(1-2): 113-128, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32086696

RESUMO

KEY MESSAGE: Using a time-course RNA-seq analysis we identified transcriptomic changes during formation of nodule-like structures (NLS) in rice and compared rice RNA-seq dataset with a nodule transcriptome dataset in Medicago truncatula. Plant hormones can induce the formation of nodule-like structures (NLS) in plant roots even in the absence of bacteria. These structures can be induced in roots of both legumes and non-legumes. Moreover, nitrogen-fixing bacteria can recognize and colonize these root structures. Therefore, identifying the genetic switches controlling the NLS organogenesis program in crops, especially cereals, can have important agricultural implications. Our recent study evaluated the transcriptomic response occurring in rice roots during NLS formation, 7 days post-treatment (dpt) with auxin, 2,4-D. In this current study, we investigated the regulation of gene expression occurring in rice roots at different stages of NLS formation: early (1-dpt) and late (14-dpt). At 1-dpt and 14-dpt, we identified 1662 and 1986 differentially expressed genes (DEGs), respectively. Gene ontology enrichment analysis revealed that the dataset was enriched with genes involved in auxin response and signaling; and in anatomical structure development and morphogenesis. Next, we compared the gene expression profiles across the three time points (1-, 7-, and 14-dpt) and identified genes that were uniquely or commonly differentially expressed at all three time points. We compared our rice RNA-seq dataset with a nodule transcriptome dataset in Medicago truncatula. This analysis revealed there is some amount of overlap between the molecular mechanisms governing nodulation and NLS formation. We also identified that some key nodulation genes were not expressed in rice roots during NLS formation. We validated the expression pattern of several genes via reverse transcriptase polymerase chain reaction (RT-PCR). The DEGs identified in this dataset may serve as a useful resource for future studies to characterize the genetic pathways controlling NLS formation in cereals.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/genética , RNA de Plantas , RNA-Seq , Conjuntos de Dados como Assunto , Perfilação da Expressão Gênica , Ontologia Genética , Medicago truncatula/genética , Oryza/anatomia & histologia , Oryza/efeitos dos fármacos , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/genética , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Proteínas Quinases/genética , Fatores de Transcrição/metabolismo , Transcriptoma
14.
ACS Appl Bio Mater ; 3(10): 6737-6745, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-35019338

RESUMO

Ponatinib (Pon) is a multi-tyrosine kinase inhibitor that demonstrated high efficiency for treating cancer. However, severe side effects caused by Pon off-targeting effects prevent its extensive use. Using our understanding into the mechanisms by which Pon is transported by bovine serum albumin in the blood, we have successfully encapsulated Pon into a biomimetic nanoparticle (NP). This lipid NP (i.e., "leukosomes") incorporates membrane proteins purified from activated leukocytes that enable immune evasion, and enhanced targeting of inflamed endothelium NPs have been characterized for their size, charge, and encapsulation efficiency. Membrane proteins enriched on the NP surface enabled modulation of Pon release. These NP formulations showed promising dose-response results on two different murine osteosarcoma cell lines, F420 and RF379. Our results indicate that our fabrication method is reproducible, nonuser-dependent, efficient in loading Pon, and applicable toward repurposing numerous therapeutic agents previously shelved due to toxicity profiles.

15.
Int J Biol Macromol ; 151: 1049-1057, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31739028

RESUMO

The objectives of this study were to optimize the conditions for the preparation of sweet potato starch containing a high proportion of slowly digestible starch (SDS) by heat-moisture treatment (HMT), and to investigate the structural properties of SDS and resistant starch (RS) fractions isolated from this modified starch. Response surface methodology evaluation of considering temperature, time, and moisture content was conducted to determine the HMT condition for maximizing SDS yield. Maximum SDS content (50.9%) was obtained after 8.6 h at 113 °C with 22.8% moisture level. Scanning electron micrographs of RS fractions displayed growth ring structure and hollow regions. X-ray diffraction patterns of SDS + RS and RS fractions were not changed by HMT. Gelatinization enthalpy of the SDS + RS fraction was decreased more than that of the RS fraction. The results indicated that the SDS fraction consisted of less perfect crystallites and amorphous regions, whereas the RS fraction was composed mostly of crystalline regions.


Assuntos
Temperatura Alta , Umidade , Ipomoea batatas/química , Amido/química , Estrutura Molecular , Polimerização , Análise Espectral , Amido/ultraestrutura
16.
PLoS One ; 14(5): e0217309, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31120967

RESUMO

Major non-legume crops can form beneficial associations with nitrogen-fixing bacteria like Azospirillum brasilense. Our current understanding of the molecular aspects and signaling that occur between important crops like rice and these nitrogen-fixing bacteria is limited. In this study, we used an experimental system where the bacteria could colonize the plant roots and promote plant growth in wild type rice and symbiotic mutants (dmi3 and pollux) in rice. Our data suggest that plant growth promotion and root penetration is not dependent on these genes. We then used this colonization model to identify regulation of gene expression at two different time points during this interaction: at 1day post inoculation (dpi), we identified 1622 differentially expressed genes (DEGs) in rice roots, and at 14dpi, we identified 1995 DEGs. We performed a comprehensive data mining to classify the DEGs into the categories of transcription factors (TFs), protein kinases (PKs), and transporters (TRs). Several of these DEGs encode proteins that are involved in the flavonoid biosynthetic pathway, defense, and hormone signaling pathways. We identified genes that are involved in nitrate and sugar transport and are also implicated to play a role in other plant-microbe interactions. Overall, findings from this study will serve as an excellent resource to characterize the host genetic pathway controlling the interactions between non-legumes and beneficial bacteria which can have long-term implications towards sustainably improving agriculture.


Assuntos
Azospirillum brasilense/fisiologia , Oryza/genética , Oryza/microbiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Interações entre Hospedeiro e Microrganismos/genética , Modelos Biológicos , Mutação , Oryza/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , RNA de Plantas/genética , RNA-Seq , Transdução de Sinais/genética , Simbiose/genética
17.
J Food Sci ; 84(6): 1362-1370, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31125129

RESUMO

In this study, starch-lipid complexes were prepared using normal corn starch (NC) and amylosucrase-modified waxy corn starch (ASWC) with myristic acid (C14:0) and palmitic acid (C16:0). The amylosucrase modification elongated branch chains in waxy corn starch leading to an increase of apparent amylose content (29.7%) similar to that of NC (29.0%). The X-ray diffraction of starch-lipid complexes revealed a V-type pattern, a clear indication of complex formation. The ability of the ASWC to complex with fatty acids was greater than that of NC. Interestingly, the changes in relative crystallinity, thermal parameters, and digestion properties according to the complexation showed opposite patterns in NC and ASWC. This study found that the structure of ASWC contributes to the formation of starch-fatty acid complexes and suggested that the ASWC can be preferred over NC in a delivery system. PRACTICAL APPLICATION: Amylopectin has been considered to be incapable of forming complexes with fatty acids due to its short chain length and steric hindrance. Through this study, an appropriate enzymatic modification of the molecular structures of waxy starches could make a complexation of waxy starches with fatty acids possible. The findings of this study suggest a promising perspective for utilization of waxy starch as a carrier material of lipophilic molecules.


Assuntos
Ácidos Graxos , Glucosiltransferases , Amido/química , Zea mays/química , Amilopectina/química , Amilose/química , Portadores de Fármacos/química , Hidrólise , Estrutura Molecular , Difração de Raios X
18.
Funct Integr Genomics ; 18(3): 315-326, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29511998

RESUMO

Auxins can induce the formation of nodule-like structures (NLS) in plant roots even in the absence of rhizobia and nitrogen-fixing bacteria can colonize these structures. Interestingly, NLS can be induced in roots of both legumes and non-legumes. However, our understanding of NLS formation in non-legumes at a molecular level is limited. This study aims to investigate NLS formation at a developmental and molecular level in Brachypodium distachyon. We treated Brachypodium roots with the synthetic auxin, 2,4-D, to induce NLS at a high frequency (> 80%) under controlled conditions. A broad base and a diffuse meristem characterized these structures. Next, we performed a comprehensive RNA-sequencing experiment to identify differentially expressed genes (DEGs) in Brachypodium roots during NLS formation. We identified 618 DEGs; several of which are promising candidates for control of NLS based on their biological and molecular functions. We validated the expression pattern of several genes via RT-PCR. Next, we compared the expression profile of Brachypodium roots with rice roots during NLS formation. We identified 76 single-copy ortholog pairs in rice and Brachypodium that are both differentially expressed during this process. Some of these genes are involved in auxin signaling, root development, and legume-rhizobia symbiosis. We established an experimental system to study NLS formation in Brachypodium at a developmental and genetic level, and used RNA-sequencing analysis to understand the molecular mechanisms controlling this root organogenesis program. Furthermore, our comparative transcriptome analysis in Brachypodium and rice identified a key set of genes for further investigating this genetic pathway in grasses.


Assuntos
Brachypodium/genética , Nódulos Radiculares de Plantas/genética , Transcriptoma , Ácidos Indolacéticos/farmacologia , Nódulos Radiculares de Plantas/efeitos dos fármacos , Nódulos Radiculares de Plantas/ultraestrutura
19.
Biochem Biophys Res Commun ; 492(2): 154-160, 2017 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-28802578

RESUMO

Induced pluripotent stem cells (iPSCs) technology is a method for generating pluripotent stem cells in vitro from fully differentiated cells such as fibroblast cells. The potential applications of iPSC technology in cell therapy and disease modeling could influence current medical practices. Despite current advances in iPSC technology, many patient-derived reprogrammed cells are not suitable for clinical trial because most protocols rely on virus-based techniques, which pose the risk of integration of the viral genome into the chromosomes. Therefore, non-viral methods such as mRNA and protein-based reprogramming are promising alternatives when generating clinically safe iPSCs. In a previous study, we generated human iPSCs using cell extracts with cell penetration peptide (CPP) for the delivery of reprogramming proteins [Kim et al. Cell Stem Cells, 2009]. In here, we show that the expression of reprogramming factors in mammalian cells and subsequent purification of these factors by FLAG-Tag could reprogram fibroblasts into iPSCs.


Assuntos
Técnicas de Reprogramação Celular/métodos , Reprogramação Celular , Fibroblastos/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Células Cultivadas , Fibroblastos/metabolismo , Expressão Gênica , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo
20.
Food Sci Biotechnol ; 26(2): 323-329, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30263546

RESUMO

Amylosucrase-treated waxy corn starch (AS) was produced to extend the chain length of amylopectin to a great extent in comparison to its native chain length. An amylopectin-palmitic acid (PA) complex was prepared by heat-treating (121°C) a starch/PA mixture and its subsequent further incubation (95°C, 24 h); moreover, its structure and digestibility were studied. Unmodified waxy starch could not complex at all, whereas elongation due to amylosucrase modification allowed amylopectin to form a complex with PA to a small extent. Complexation between AS and PA caused a decrease in relative crystallinity. The AS-PA complex displayed an endothermic peak representing type I inclusion complexes rather than type II complexes. The formation of complexes did not significantly affect the in vitro digestibility maintaining the low digestibility of AS resulting from extremely small amounts of complexes and the type of complex.

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