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1.
Adv Biotechnol (Singap) ; 2(2): 17, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38756984

RESUMO

The global demand for animal-derived foods has led to a substantial expansion in ruminant production, which has raised concerns regarding methane emissions. To address these challenges, microalgal species that are nutritionally-rich and contain bioactive compounds in their biomass have been explored as attractive feed additives for ruminant livestock production. In this review, we discuss the different microalgal species used for this purpose in recent studies, and review the effects of microalgal feed supplements on ruminant growth, performance, health, and product quality, as well as their potential contributions in reducing methane emissions. We also examine the potential complexities of adopting microalgae as feed additives in the ruminant industry.

2.
Cryobiology ; 114: 104846, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38295926

RESUMO

Petunia × Calibrachoa 'Light Yellow' (× Petchoa 'Light Yellow') is a kind of perennial herbaceous flower obtained through intergeneric hybridization of Petunia and Calibrachoa with high ornamental value and wide application, facing challenges in seed acquisition. Expanding propagation through tissue culture is an economically efficient means. Hence, establishing an effective procedure for the storage of callus is essential for × Petchoa 'Light Yellow'. Cryopreservation is an effective method for the in vitro propagation and long-term preservation of × Petchoa 'Light Yellow' germplasms. For formulating the optimization of the vitrification procedure, first, an orthogonal experimental design was employed to pinpoint critical steps in the vitrification protocol (pre-culture, osmoprotection, dehydration, and dilution) for Petunia × Calibrachoa callus tissues and then five additional factors (pre-culture, osmoprotection I and II, dehydration, and dilution) were optimized to further reduce the sample water content and enhance cell viability levels. The vitrification procedure was described as follows: callus tissues were precultured in MS solid medium with 0.3 M sucrose for 5 d, incubated with osmoprotection solution I and II for 15 min at 25 °C, respectively, cryoprotected with PVS2 for 30 min at 0 °C, and rapidly immersed in liquid nitrogen. Cryopreserved callus tissues were then diluted in MS liquid medium with 1.2 M sucrose for 20 min at 25 °C and recovered on MS solid medium with 0.5 mg/L 6-BA and 0.1 mg/L NAA, and sucrose. The cell viability measured by TTC staining was approximately 16 %-18 % after 72 h-recovery. Following 45 days, the relative survival of callus reached up to 49.48 %. Furthermore, EST-SSR analysis showed no significant difference in the genetic stability of cryopreserved callus compared to the control. Based on the cryopreservation of × Petchoa 'Light Yellow' callus, we further evaluated the response of callus water contents to the osmotic stress in the optimized and original protocols (CK) for a higher cryopreservation survival. A comparative analysis of water content demonstrated that the procedure of gradual and gentle dehydration significantly improved water content and cell survival. Ultrastructural changes between cryopreserved and non-cryopreserved callus were examined and high vacuolation emerged as a key determinant, indicating its substantial impact on the low survival of cryopreserved cells, which should help us to understand the effectiveness of osmotic protectants in dehydration.


Assuntos
Criopreservação , Petunia , Criopreservação/métodos , Crioprotetores/farmacologia , Desidratação , Vitrificação , Sacarose , Água , Brotos de Planta/fisiologia
3.
Plants (Basel) ; 12(10)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37653976

RESUMO

Alfalfa (Medicago sativa L.) is a widely grown perennial leguminous forage crop with a number of positive attributes. However, despite its moderate ability to tolerate saline soils, which are increasing in prevalence worldwide, it suffers considerable yield declines under these growth conditions. While a general framework of the cascade of events involved in plant salinity response has been unraveled in recent years, many gaps remain in our understanding of the precise molecular mechanisms involved in this process, particularly in non-model yet economically important species such as alfalfa. Therefore, as a means of further elucidating salinity response mechanisms in this species, we carried out in-depth physiological assessments of M. sativa cv. Beaver, as well as transcriptomic and untargeted metabolomic evaluations of leaf tissues, following extended exposure to salinity (grown for 3-4 weeks under saline treatment) and control conditions. In addition to the substantial growth and photosynthetic reductions observed under salinity treatment, we identified 1233 significant differentially expressed genes between growth conditions, as well as 60 annotated differentially accumulated metabolites. Taken together, our results suggest that changes to cell membranes and walls, cuticular and/or epicuticular waxes, osmoprotectant levels, antioxidant-related metabolic pathways, and the expression of genes encoding ion transporters, protective proteins, and transcription factors are likely involved in alfalfa's salinity response process. Although some of these alterations may contribute to alfalfa's modest salinity resilience, it is feasible that several may be disadvantageous in this context and could therefore provide valuable targets for the further improvement of tolerance to this stress in the future.

4.
Methods Mol Biol ; 2659: 219-239, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37249896

RESUMO

CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9) has become a breeding tool of choice for eliciting targeted genetic alterations in crop species as a means of improving a wide range of agronomic traits, including disease resistance, in recent years. With the recent development of CRISPR/Cas9 technology in Medicago sativa (alfalfa), which is an important perennial forage legume grown worldwide, its use for the enhancement of pathogen resistance is almost certainly on the horizon. In this chapter, we present detailed procedures for the generation of a single nonhomologous end-joining-derived indel at a precise genomic locus of alfalfa via CRISPR/Cas9. This method encompasses crucial steps in this process, including guide RNA design, binary CRISPR vector construction, Agrobacterium-mediated transformation of alfalfa explants, and molecular assessments of transformed genotypes for transgene and edit identification.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Edição de Genes/métodos , Sistemas CRISPR-Cas/genética , Medicago sativa/genética , Resistência à Doença/genética , Melhoramento Vegetal , Mutação INDEL
5.
Plant J ; 115(3): 833-845, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37129256

RESUMO

Phosphatidylcholine has essential functions in many eukaryotic cells, and its de novo biosynthesis is rate-limited by cytidine triphosphate:phosphocholine cytidylyltransferase (CCT). Although the biological and biochemical functions of CCT have been reported in mammals and several plants, this key enzyme has yet to be examined at a genome-wide level. As such, certain fundamental questions remain unanswered, including the evolutionary history, genetic and functional relationships, and structural variations among CCTs in the green lineage. In the current study, in-depth phylogenetic analysis, as well as the conservation and diversification in CCT gene structure and motif patterns, indicated that CCTs exist broadly in chlorophytes, bryophytes, lycophytes, monilophytes, gymnosperms, early-diverging angiosperms, monocots, and eudicots, and form eight relatively conserved clades. To further explore the potential function of selection pressure, we conducted extensive selection pressure analysis with a representative CCT gene, CCT1 from the model plant Arabidopsis thaliana (AthCCT1), and identified two positive selection sites, L59 and Q156. Site-directed mutagenesis and in vitro enzyme assays demonstrated that these positively selected sites were indeed important for the activity and substrate affinity of AthCCT1, and subsequent 3D structure analyses explained the potential biochemical mechanism. Taken together, our results unraveled the evolution and diversity of CCTs in the green lineage, as well as their association with the enzyme's biochemical and structural properties, and expanded our understanding of this important enzyme at the genome-wide level.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Animais , Fosforilcolina , Filogenia , Plantas/genética , Colina-Fosfato Citidililtransferase/genética , Colina-Fosfato Citidililtransferase/química , Arabidopsis/genética , Mamíferos , Proteínas de Arabidopsis/genética
6.
Plant Biotechnol J ; 21(9): 1734-1744, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36762506

RESUMO

Plant lipids have essential biological roles in plant development and stress responses through their functions in cell membrane formation, energy storage and signalling. Vegetable oil, which is composed mainly of the storage lipid triacylglycerol, also has important applications in food, biofuel and oleochemical industries. Lipid biosynthesis occurs in multiple subcellular compartments and involves the coordinated action of various pathways. Although biochemical and molecular biology research over the last few decades has identified many proteins associated with lipid metabolism, our current understanding of the dynamic protein interactomes involved in lipid biosynthesis, modification and channelling is limited. This review examines advances in the identification and characterization of protein interactomes involved in plant lipid biosynthesis, with a focus on protein complexes consisting of different subunits for sequential reactions such as those in fatty acid biosynthesis and modification, as well as transient or dynamic interactomes formed from enzymes in cooperative pathways such as assemblies of membrane-bound enzymes for triacylglycerol biosynthesis. We also showcase a selection of representative protein interactome structures predicted using AlphaFold2, and discuss current and prospective strategies involving the use of interactome knowledge in plant lipid biotechnology. Finally, unresolved questions in this research area and possible approaches to address them are also discussed.


Assuntos
Lipídeos , Plantas , Estudos Prospectivos , Plantas/genética , Plantas/metabolismo , Triglicerídeos/metabolismo , Metabolismo dos Lipídeos , Biotecnologia
7.
Plant Physiol ; 192(1): 426-441, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36805986

RESUMO

Glycerolipids are the most abundant lipids in microalgae, and glycerol-3-phosphate:acyl-CoA acyltransferase (GPAT) plays an important role in their biosynthesis. However, the biochemical and biological functions of algal GPAT remain poorly characterized. Here, we characterized the endoplasmic reticulum (ER)-associated GPAT of the model unicellular green alga Chlamydomonas reinhardtii (CrGPATer). Enzymatic assays indicated that CrGPATer is an sn-1 acyltransferase using a variety of acyl-CoAs as the acyl donor. Subcellular localization revealed that CrGPATer was associated with ER membranes and lipid droplets. We constructed overexpression (OE) and knockdown (KD) transgenic C. reinhardtii lines to investigate the in vivo function of CrGPATer. Lipidomic analysis indicated that CrGPATer OE enhanced the cellular content of galactolipids, especially monogalactosyldiacylglycerol, under nitrogen deficiency stress. Correspondingly, CrGPATer KD lines contained lower contents of galactolipids than the control. Feeding experiments with labeled phosphatidic acid revealed that the intermediate of the eukaryotic Kennedy pathway could be used for galactolipid biosynthesis in the chloroplasts. These results provided multiple lines of evidence that the eukaryotic Kennedy pathway mediated by CrGPATer may be involved in galactolipid biosynthesis in C. reinhardtii. OE of CrGPATer significantly increased the content of triacylglycerol and the yield of biomass. Moreover, the content and yield of 1, 3-olein-2-palmitin, a high-value lipid that can be used as an alternative for human milk fat in infant formula, were significantly enhanced in the OE transgenic lines. Taken together, this study provided insights into the biochemical and biological functions of CrGPATer and its potential as a genetic engineering target in functional lipid manufacturing.


Assuntos
Galactolipídeos , Microalgas , Humanos , Aciltransferases/metabolismo , Galactolipídeos/metabolismo , Glicerol/metabolismo , Glicerol-3-Fosfato O-Aciltransferase/genética , Glicerol-3-Fosfato O-Aciltransferase/química , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Microalgas/genética , Microalgas/metabolismo , Fosfatos/metabolismo , Plantas/metabolismo , Triglicerídeos/metabolismo , Metabolismo dos Lipídeos
8.
Plant Cell Environ ; 46(4): 1278-1294, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35698268

RESUMO

Glycerolipids are essential for rice development and grain quality but its genetic regulation remains unknown. Here we report its genetic base using metabolite-based genome-wide association study and metabolite-based quantitative traits locus (QTL) analyses based on lipidomic profiles of seeds from 587 Asian cultivated rice accessions and 103 chromosomal segment substitution lines, respectively. We found that two genes encoding phosphatidylcholine (PC):diacylglycerol cholinephosphotransferase (OsLP1) and granule-bound starch synthase I (Waxy) contribute to variations in saturated triacylglycerol (TAG) and lyso-PC contents, respectively. We demonstrated that allelic variation in OsLP1 sequence between indica and japonica results in different enzymatic preference for substrate PC-16:0/16:0 and different saturated TAG levels. Further evidence demonstrated that OsLP1 also affects heading date, and that co-selection of OsLP1 and a flooding-tolerant QTL in Aus results in the abundance of saturated TAGs associated with flooding tolerance. Moreover, we revealed that the sequence polymorphisms in Waxy has pleiotropic effects on lyso-PC and amylose content. We proposed that rice seed glycerolipids have been unintentionally shaped during natural and artificial selection for adaptive or import seed quality traits. Collectively, our findings provide valuable genetic resources for rice improvement and evolutionary insights into seed glycerolipid variations in rice.


Assuntos
Oryza , Oryza/genética , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas/genética , Fenótipo , Sementes/genética
9.
Prog Lipid Res ; 88: 101181, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35820474

RESUMO

Acyl-CoA:diacylglycerol acyltransferase (DGAT, EC 2.3.1.20) catalyzes the last reaction in the acyl-CoA-dependent biosynthesis of triacylglycerol (TAG). DGAT activity resides mainly in DGAT1 and DGAT2 in eukaryotes and bifunctional wax ester synthase-diacylglycerol acyltransferase (WSD) in bacteria, which are all membrane-bound proteins but exhibit no sequence homology to each other. Recent studies also identified other DGAT enzymes such as the soluble DGAT3 and diacylglycerol acetyltransferase (EaDAcT), as well as enzymes with DGAT activities including defective in cuticular ridges (DCR) and steryl and phytyl ester synthases (PESs). This review comprehensively discusses research advances on DGATs in prokaryotes and eukaryotes with a focus on their biochemical properties, physiological roles, and biotechnological and therapeutic applications. The review begins with a discussion of DGAT assay methods, followed by a systematic discussion of TAG biosynthesis and the properties and physiological role of DGATs. Thereafter, the review discusses the three-dimensional structure and insights into mechanism of action of human DGAT1, and the modeled DGAT1 from Brassica napus. The review then examines metabolic engineering strategies involving manipulation of DGAT, followed by a discussion of its therapeutic applications. DGAT in relation to improvement of traits of farmed animals is also discussed along with DGATs in various other eukaryotic organisms.


Assuntos
Acil Coenzima A , Diacilglicerol O-Aciltransferase , Animais , Humanos , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/química , Diacilglicerol O-Aciltransferase/metabolismo , Acil Coenzima A/metabolismo , Engenharia Metabólica , Triglicerídeos , Eucariotos , Ésteres/metabolismo
10.
Geroscience ; 44(4): 2319-2336, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35581512

RESUMO

Exploring individual hallmarks of brain ageing is important. Here, we propose the age-related glucose metabolism pattern (ARGMP) as a potential index to characterize brain ageing in cognitively normal (CN) elderly people. We collected 18F-fluorodeoxyglucose (18F-FDG) PET brain images from two independent cohorts: the Alzheimer's Disease Neuroimaging Initiative (ADNI, N = 127) and the Xuanwu Hospital of Capital Medical University, Beijing, China (N = 84). During follow-up (mean 80.60 months), 23 participants in the ADNI cohort converted to cognitive impairment. ARGMPs were identified using the scaled subprofile model/principal component analysis method, and cross-validations were conducted in both independent cohorts. A survival analysis was further conducted to calculate the predictive effect of conversion risk by using ARGMPs. The results showed that ARGMPs were characterized by hypometabolism with increasing age primarily in the bilateral medial superior frontal gyrus, anterior cingulate and paracingulate gyri, caudate nucleus, and left supplementary motor area and hypermetabolism in part of the left inferior cerebellum. The expression network scores of ARGMPs were significantly associated with chronological age (R = 0.808, p < 0.001), which was validated in both the ADNI and Xuanwu cohorts. Individuals with higher network scores exhibited a better predictive effect (HR: 0.30, 95% CI: 0.1340 ~ 0.6904, p = 0.0068). These findings indicate that ARGMPs derived from CN participants may represent a novel index for characterizing brain ageing and predicting high conversion risk into cognitive impairment.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Idoso , Doença de Alzheimer/complicações , Tomografia por Emissão de Pósitrons/métodos , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Fluordesoxiglucose F18/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Envelhecimento , Glucose/metabolismo
11.
Front Plant Sci ; 13: 799142, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35251078

RESUMO

Clubroot, caused by the obligate parasite Plasmodiophora brassicae, is one of the most devastating diseases of canola (Brassica napus) in Canada. The identification of novel genes that contribute to clubroot resistance is important for the sustainable management of clubroot, as these genes may be used in the development of resistant canola cultivars. Phospholipase As (PLAs) play important roles in plant defense signaling and stress tolerance, and thus are attractive targets for crop breeding. However, since canola is an allopolyploid and has multiple copies of each PLA gene, it is time-consuming to test the functions of PLAs directly in this crop. In contrast, the model plant Arabidopsis thaliana has a simpler genetic background and only one copy of each PLA. Therefore, it would be reasonable and faster to validate the potential utility of PLA genes in Arabidopsis first. In this study, we identified seven homozygous atpla knockout/knockdown mutants of Arabidopsis, and tested their performance following inoculation with P. brassicae. Four mutants (pla1-iiα, pla1-iγ3, pla1-iii, ppla-iiiß, ppla-iiiδ) developed more severe clubroot than the wild-type, suggesting increased susceptibility to P. brassicae. The homologs of these Arabidopsis PLAs (AtPLAs) in B. napus (BnPLAs) were identified through Blast searches and phylogenic analysis. Expression of the BnPLAs was subsequently examined in transcriptomic datasets generated from canola infected by P. brassicae, and promising candidates for further characterization identified.

12.
Bioresour Technol ; 351: 127020, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35307524

RESUMO

The expanding use of fossil fuels has caused concern in terms of both energy security and environmental issues. Therefore, attempts have been made worldwide to promote the development of renewable energy sources, among which biofuel is especially attractive. Compared to other biofuels, lipid-derived biofuels have a higher energy density and better compatibility with existing infrastructure, and their performance can be readily improved by adjusting the chemical composition of lipid feedstocks. This review thus addresses the intrinsic interactions between lipid feedstocks and lipid-based biofuels, including biodiesel, and renewable equivalents to conventional gasoline, diesel, and jet fuel. Advancements in lipid-associated biofuel technology, as well as the properties and applicability of various lipid sources in terms of biofuel production, are also discussed. Furthermore, current progress in lipid production and profile optimization in the context of plant lipids, microbial lipids, and animal fats are presented to provide a wider context of lipid-based biofuel technology.


Assuntos
Biocombustíveis , Gasolina , Combustíveis Fósseis , Lipídeos , Tecnologia
13.
Front Pharmacol ; 13: 803855, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35295336

RESUMO

Tetradium ruticarpum (TR) is widely used in Asia to treat gastrointestinal disorders and pain. Stir-frying with licorice aqueous extract is a traditional processing procedure of TR formed in a long-term practice and performed before clinical application, and believed to reduce TR's toxicity. However, its toxicity and possible toxicity attenuation approach are yet to be well investigated. Subacute toxicity and metabolomics studies were conducted to help understand the toxicity of TR. The subacute toxicity assessment indicated that 3 fold of the recommended therapeutic dose of TR did not show obvious subacute toxicity in rats. Although an extremely high dose (i.e., 60 fold of the recommended dose) may cause toxicity in rats, it reversed to normal after 2 weeks of recovery. Hepatocellular injury was the major toxic phenotype of TR-induced liver damage, indicating as aspartate aminotransferase (AST) and liver index increasing, with histopathologic findings as local hepatocyte necrosis, focal inflammatory cell infiltration, slightly bile duct hyperplasia, and partial hepatocyte vacuolation. Moreover, we evaluated the impact of processing in toxicity. TR processed with licorice could effectively reduce drug-induced toxicity, which is a valuable step in TR pretreatment before clinical application. Metabolomics profiling revealed that primary bile acid biosynthesis, steroid biosynthesis, and arachidonic acid metabolism were mainly involved in profiling the toxicity metabolic regulatory network. The processing procedure could back-regulate these three pathways, and may be in an Aryl hydrocarbon Receptor (AhR) dependent manner to alleviate the metabolic perturbations induced by TR. 7α-hydroxycholesterol, calcitriol, and taurocholic acid were screened and validated as the toxicity biomarkers of TR for potential clinical translation. Overall, the extensive subacute toxicity evaluation and metabolomic analysis would not only expand knowledge of the toxicity mechanisms of TR, but also provide scientific insight of traditional processing theory, and support clinical rational use of TR.

14.
Plants (Basel) ; 10(10)2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34685916

RESUMO

Alfalfa (Medicago sativa L.) is an extensively grown perennial forage legume, and although it is relatively drought tolerant, it consumes high amounts of water and depends upon irrigation in many regions. Given the progressive decline in water available for irrigation, as well as an escalation in climate change-related droughts, there is a critical need to develop alfalfa cultivars with improved drought resilience. M. sativa subsp. falcata is a close relative of the predominantly cultivated M. sativa subsp. sativa, and certain accessions have been demonstrated to exhibit superior performance under drought. As such, we endeavoured to carry out comparative physiological, biochemical, and transcriptomic evaluations of an as of yet unstudied drought-tolerant M. sativa subsp. falcata accession (PI 641381) and a relatively drought-susceptible M. sativa subsp. sativa cultivar (Beaver) to increase our understanding of the molecular mechanisms behind the enhanced ability of falcata to withstand water deficiency. Our findings indicate that unlike the small number of falcata genotypes assessed previously, falcata PI 641381 may exploit smaller, thicker leaves, as well as an increase in the baseline transcriptional levels of genes encoding particular transcription factors, protective proteins, and enzymes involved in the biosynthesis of stress-related compounds. These findings imply that different falcata accessions/genotypes may employ distinct drought response mechanisms, and the study provides a suite of candidate genes to facilitate the breeding of alfalfa with enhanced drought resilience in the future.

15.
Curr Alzheimer Res ; 18(6): 492-498, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34598665

RESUMO

BACKGROUND: Education could offer a protective effect on cognition in individuals with Subjective Cognitive Decline (SCD), which is considered to be the early stage of Alzheimer's Disease (AD). However, the effect of education on cognition in SCD individuals with SCD-plus features is not clear. OBJECTIVE: The aim of the study was to explore the effect of education on cognition in SCD individuals with SCD-plus features. METHODS: A total of 234 individuals with SCD were included from the Sino Longitudinal Study on Cognitive Decline (SILCODE). Cognition was assessed across 4 domains (memory, executive, language, and general cognitive functions). Multiple linear regression models were constructed to examine the effect of education on cognitive scores in individuals without worry (n=91) and with worry (n=143). Furthermore, we assessed differences in effects between APOE ε4 noncarriers and APOE ε4 carriers in both groups. RESULTS: Multiple linear regression analysis showed a positive effect of education on memory, executive, and language cognition in individuals without worry and all cognitive domains in individuals with worry. Furthermore, we found a positive effect of education on executive cognition in APOE ε4 noncarriers without worry and language and general cognition in APOE ε4 carriers without worry. Meanwhile, education had a positive effect on all cognitive domains in APOE ε4 noncarriers with worry and executive, language, and general cognition in APOE ε4 carriers with worry. CONCLUSION: This study indicates that education has the potential to delay or reduce cognitive decline in SCD individuals with SCD-plus features.


Assuntos
Ansiedade/psicologia , Apolipoproteína E4/genética , Cognição/fisiologia , Disfunção Cognitiva/prevenção & controle , Escolaridade , Testes Neuropsicológicos/estatística & dados numéricos , Idoso , Doença de Alzheimer/genética , China , Feminino , Heterozigoto , Humanos , Estudos Longitudinais , Masculino , Neuroimagem
16.
J Agric Food Chem ; 69(33): 9616-9624, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34428902

RESUMO

Punicic acid (PuA) is a high-value edible conjugated fatty acid with strong bioactivities and has important potential applications in nutraceutical, pharmaceutical, feeding, and oleochemical industries. Since the production of PuA is severely limited by the fact that its natural source (pomegranate seed oil) is not readily available on a large scale, there is considerable interest in understanding the biosynthesis and accumulation of this plant-based unusual fatty acid in transgenic microorganisms to support the rational design of biotechnological approaches for PuA production via fermentation. Here, we tested the effectiveness of genetic engineering and precursor supply in PuA production in the model yeast strain Saccharomyces cerevisiae. The results revealed that the combination of precursor feeding and co-expression of selected genes in acyl channeling processes created an effective "push-pull" approach to increase PuA content, which could prove valuable in future efforts to produce PuA in industrial yeast and other microorganisms via fermentation.


Assuntos
Ácidos Linolênicos , Saccharomyces cerevisiae , Fermentação , Engenharia Genética , Saccharomyces cerevisiae/genética
18.
Plant Cell Rep ; 40(9): 1647-1663, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34215912

RESUMO

KEY MESSAGE: AIL7 over-expression modulates fatty acid biosynthesis and triacylglycerol accumulation in Arabidopsis developing seeds through the transcriptional regulation of associated genes. Seed fatty acids (FAs) and triacylglycerol (TAG) contribute to many functions in plants, and seed lipids have broad food, feed and industrial applications. As a result, an enormous amount of attention has been dedicated towards uncovering the regulatory cascade responsible for the fine-tuning of the lipid biosynthetic pathway in seeds, which is regulated in part through the action of LEAFY COTYLEDON1, ABSCISSIC ACID INSENSITIVE 3, FUSCA3 and LEC2 (LAFL) transcription factors. Although AINTEGUMENTA-LIKE 7 (AIL7) is involved in meristematic function and shoot phyllotaxy, its effect in the context of lipid biosynthesis has yet to be assessed. Here, we generated AIL7 seed-specific over-expression lines and found that they exhibited significant alterations in FA composition and decreased total lipid accumulation in seeds. Seeds and seedlings from transgenic lines also exhibited morphological deviations compared to wild type. Correspondingly, RNA-Seq analysis demonstrated that the expression of many genes related to FA biosynthesis and TAG breakdown were significantly altered in developing siliques from transgenic lines compared to wild-type plants. The seed-specific over-expression of AIL7 also altered the expression profiles of many genes related to starch metabolism, photosynthesis and stress response, suggesting further roles for AIL7 in plants. These findings not only advance our understanding of the lipid biosynthetic pathway in seeds, but also provide evidence for additional functions of AIL7, which could prove valuable in downstream breeding and/or metabolic engineering endeavors.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Ligação a DNA/genética , Ácidos Graxos/biossíntese , Sementes/metabolismo , Fatores de Transcrição/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ácidos Graxos/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Óleos de Plantas/metabolismo , Plantas Geneticamente Modificadas , Plântula/genética , Plântula/crescimento & desenvolvimento , Sementes/genética , Sementes/crescimento & desenvolvimento , Amido/genética , Amido/metabolismo , Fatores de Transcrição/metabolismo , Triglicerídeos/metabolismo
19.
Biomed Res Int ; 2021: 5538323, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34195266

RESUMO

BACKGROUND: Subjective cognitive decline (SCD) is the earliest symptom stage of Alzheimer's disease (AD). Previous studies have shown that the study setting is an important influence factor of SCD. However, the effect of this factor among a Chinese population with SCD is not clear. Here, we aim to compare the clinical characteristics of SCD between a convenience and a population-based sample in China. METHODS: We included a convenience sample of 212 SCD subjects and a population-based sample of 110 SCD subjects. We performed univariate analysis to evaluate the between-group differences in sociodemographic characteristics, neuropsychological performance, psychiatric conditions, different cognitive domains, and the SCD-plus criteria. Multiple linear regression model was established, adjusted for sex, age, and education, and compared the neuropsychological performance between the groups. RESULTS: The convenience sample had more years of education, a higher family history of dementia, and higher neuropsychological and anxiety depression score than the population-based sample. Using sex, age, education, group as the independent variables, and neuropsychological score as the dependent variable, multiple linear regression model was established; a statistically significant neuropsychological score difference (MoCA-B, AVLT-H-N4, AVLT-H-N5, AVLT-H-N7, AFT, and STT-B) was found between the two samples. In the SCD cognitive domains, the population-based sample had more complaints about declines in their language and planning domains. For SCD-plus criteria in memory domain, the convenience sample had more complaints, worry, and cognitive decline within the last 5 years, along with medical help-seeking. CONCLUSION: There were some different characteristics among SCD individuals between convenience samples and population-based samples in China.


Assuntos
Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/terapia , Projetos de Pesquisa , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , China , Feminino , Geriatria/métodos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Análise de Regressão , Inquéritos e Questionários
20.
Int J Mol Sci ; 22(9)2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-34063617

RESUMO

A lot of researches have been focused on the evolution and function of MYB transcription factors (TFs). For revealing the formation of petunia flower color diversity, MYB gene family in petunia was identified and analyzed. In this study, a total of 155 MYB genes, including 40 1R-MYBs, 106 R2R3-MYBs, 7 R1R2R3-MYBs and 2 4R-MYBs, have been identified in the Petunia axillaris genome. Most R2R3 genes contain three exons and two introns, whereas the number of PaMYB introns varies from 0 to 12. The R2R3-MYB members could be divided into 28 subgroups. Analysis of gene structure and protein motifs revealed that members within the same subgroup presented similar exon/intron and motif organization, further supporting the results of phylogenetic analysis. Genes in subgroup 10, 11 and 21 were mainly expressed in petal, not in vegetative tissues. Genes in subgroup 9, 19, 25 and 27 expressed in all tissues, but the expression patterns of each gene were different. According to the promoter analysis, five R2R3-MYB and two MYB-related genes contained MBSI cis-element, which was involved in flavonoid biosynthetic regulation. PaMYB100/DPL has been reported to positively regulate to pigmentation. However, although PaMYB82, PaMYB68 and Pa1RMYB36 contained MBSI cis-element, their function in flavonoid biosynthesis has not been revealed. Consistent with existing knowledge, PaMYBs in subgroup 11 had similar function to AtMYBs in subgroup 6, genes in which played an important role in anthocyanin biosynthesis. In addition, PaMYB1 and PaMYB40 belonged to P9 (S7) and were potentially involved in regulation of flavonoid synthesis in petunia vegetative organs. This work provides a comprehensive understanding of the MYB gene family in petunia and lays a significant foundation for future studies on the function and evolution of MYB genes in petunia.


Assuntos
Antocianinas/biossíntese , Genes myb/genética , Petunia/genética , Fatores de Transcrição/genética , Antocianinas/genética , Proteínas de Arabidopsis/genética , Flores/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta/genética , Família Multigênica/genética , Filogenia , Pigmentação/genética , Plantas Geneticamente Modificadas/genética , Regiões Promotoras Genéticas , Fatores de Transcrição/classificação , Fatores de Transcrição/isolamento & purificação
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