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1.
Sci Adv ; 10(42): eadq4941, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39423261

RESUMO

Renewable alternatives for nonelectrifiable fossil-derived chemicals are needed and plant matter, the most abundant biomass on Earth, provide an ideal feedstock. However, the heterogeneous polymeric composition of lignocellulose makes conversion difficult. Lignin presents a formidable barrier to fermentation of nonpretreated biomass. Extensive chemical and enzymatic treatments can liberate fermentable carbohydrates from plant biomass, but microbial routes offer many advantages, including concomitant conversion to industrial chemicals. Here, testing of lignin content of nonpretreated biomass using the cellulolytic thermophilic bacterium, Anaerocellum bescii, revealed that the primary microbial degradation barrier relates to methoxy substitutions in lignin. This contrasts with optimal lignin composition for chemical pretreatment that favors high S/G ratio and low H lignin. Genetically modified poplar trees with diverse lignin compositions confirm these findings. In addition, poplar trees with low methoxy content achieve industrially relevant levels of microbial solubilization without any pretreatments and with no impact on tree fitness in greenhouse.


Assuntos
Biomassa , Fermentação , Lignina , Populus , Lignina/metabolismo , Populus/metabolismo , Populus/genética , Bactérias/metabolismo , Bactérias/genética , Plantas/metabolismo
2.
PLoS One ; 19(9): e0309515, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39231197

RESUMO

Shortening analgesic onset has been researched and it has been documented that prewarming epidural medications to body temperature (37°C) prior to administration increases medication efficacy. Our double-blind randomized controlled trial was designed to investigate if a lower degree of prewarming in providers' pockets could achieve similar results without the need of a bedside incubator. A total of 136 parturients were randomized into either the pocket-warmed group or the room temperature group to receive 10 mL of 0.125% bupivacaine with 2 µg/mL fentanyl epidural bolus at either the 27.8 ±1.7°C or 22.1 ±1.0°C temperatures, respectively. Primary outcome, time to analgesic onset (verbal rating scale pain score ≤ 3) was recorded in 0-, 5-, 10-, 15-, 20-, 30-, and 60-minutes intervals. It was observed that the pocket-warming group (n = 64) and room temperature group (n = 72) had no significant difference of analgesic onset time (median 8 vs. 6.2 minutes; p = 0.322). The incidence of adverse events such as hypotension, fever (≥ 38°C), nausea, vomiting, and number of top-off epidural boluses, as well as patient satisfaction rates and mode of delivery, were not significantly different between the groups as well. Further research is warranted to confirm these findings and explore the impact of different temperatures on analgesic onset time as well as the logistical issues associated with their clinical implementations.


Assuntos
Analgesia Epidural , Bupivacaína , Fentanila , Humanos , Feminino , Fentanila/administração & dosagem , Fentanila/efeitos adversos , Analgesia Epidural/métodos , Bupivacaína/administração & dosagem , Adulto , Método Duplo-Cego , Gravidez , Analgesia Obstétrica/métodos , Analgesia Obstétrica/efeitos adversos , Anestésicos Locais/administração & dosagem , Adulto Jovem
3.
Sci Rep ; 14(1): 19349, 2024 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164287

RESUMO

Inhibition of translation initiation using eIF4A inhibitors like (-)-didesmethylrocaglamide [(-)-DDR] and (-)-rocaglamide [(-)-Roc] is a potential cancer treatment strategy as they simultaneously diminish multiple oncogenic drivers. We showed that human and dog osteosarcoma cells expressed higher levels of eIF4A1/2 compared with mesenchymal stem cells. Genetic depletion of eIF4A1 and/or 2 slowed osteosarcoma cell growth. To advance preclinical development of eIF4A inhibitors, we demonstrated the importance of (-)-chirality in DDR for growth-inhibitory activity. Bromination of DDR at carbon-5 abolished growth-inhibitory activity, while acetylating DDR at carbon-1 was tolerated. Like (-)-DDR, (±)-DDR, and (-)-Roc, (±)-DDR-acetate increased γH2A.X levels and induced G2/M arrest and apoptosis. Consistent with translation inhibition, these rocaglates decreased the levels of several mitogenic kinases, the STAT3 transcription factor, and the stress-activated protein kinase p38. However, phosphorylated p38 was greatly enhanced in treated cells, suggesting activation of stress response pathways. RNA sequencing identified RHOB as a top upregulated gene in both (-)-DDR- and (-)-Roc-treated osteosarcoma cells, but the Rho inhibitor Rhosin did not enhance the growth-inhibitory activity of (-)-DDR or (-)-Roc. Nonetheless, these rocaglates potently suppressed tumor growth in a canine osteosarcoma patient-derived xenograft model. These results suggest that these eIF4A inhibitors can be leveraged to treat both human and dog osteosarcomas.


Assuntos
Fator de Iniciação 4A em Eucariotos , Osteossarcoma , Cães , Animais , Humanos , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Osteossarcoma/metabolismo , Linhagem Celular Tumoral , Fator de Iniciação 4A em Eucariotos/antagonistas & inibidores , Fator de Iniciação 4A em Eucariotos/metabolismo , Camundongos , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Proliferação de Células/efeitos dos fármacos , Benzofuranos/farmacologia
4.
Res Sq ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38947012

RESUMO

Inhibition of translation initiation using eIF4A inhibitors like (-)-didesmethylrocaglamide [(-)-DDR] and (-)-rocaglamide [(-)-Roc] is a potential cancer treatment strategy as they simultaneously diminish multiple oncogenic drivers. We showed that human and dog osteosarcoma cells expressed high levels of eIF4A1/2, particularly eIF4A2. Genetic depletion of eIF4A1 and/or 2 slowed osteosarcoma cell growth. To advance preclinical development of eIF4A inhibitors, we demonstrated the importance of (-)-chirality in DDR for growth-inhibitory activity. Bromination of DDR at carbon-5 abolished growth-inhibitory activity, while acetylating DDR at carbon-1 was tolerated. Like DDR and Roc, DDR-acetate increased the γH2A.X levels and induced G2/M arrest and apoptosis. Consistent with translation inhibition, these rocaglates decreased the levels of several mitogenic kinases, the STAT3 transcription factor, and the stress-activated protein kinase p38. However, phosphorylated p38 was greatly enhanced in treated cells, suggesting activation of stress response pathways. RNA sequencing identified RHOB as a top upregulated gene in both DDR- and Roc-treated osteosarcoma cells, but the Rho inhibitor Rhosin did not enhance the growth-inhibitory activity of (-)-DDR or (-)-Roc. Nonetheless, these rocaglates potently suppressed tumor growth in a canine osteosarcoma patient-derived xenograft model. These results suggest that these eIF4A inhibitors can be leveraged to treat both human and dog osteosarcomas.

5.
LGBT Health ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557209

RESUMO

Purpose: Lesbian, gay, bisexual, transgender, and queer (LGBTQ) individuals are more likely to smoke than non-LGBTQ individuals. Smoking has been posited as a coping mechanism for LGBTQ individuals facing minority stress. However, the exact relationship between minority stress and smoking behaviors among LGBTQ individuals is unclear. Therefore, the purpose of this systematic review was to examine how minority stress processes are associated with smoking behaviors for LGBTQ individuals. Methods: Searches of the PubMed and PsycINFO databases were conducted for smoking-, LGBTQ-, and minority stress-related terms. No date, geographic, or language limits were used. For inclusion, the study must have (1) been written in English, (2) had an LGBTQ group as the study population or a component of the study population, (3) assessed the cigarette smoking status of patients, and (4) assessed at least one minority stress-related process (internalized stigma, perceived stigma, or prejudice events). Results: The final review included 44 articles. Aside from two outlier studies, all of the reviewed studies exhibited that increased levels of minority stress processes (internalized queerphobia, perceived stigma, and prejudice events) were associated with increased probability of cigarette use in LGBTQ individuals. Increased minority stress was also associated with greater psychological distress/mental health decline. Conclusion: The findings of this review suggest that minority stress processes represent a contributing factor to smoking health disparities in LGBTQ populations. These results highlight the need for smoking cessation and prevention programs to address minority stress and improve smoking disparities in these populations.

6.
New Phytol ; 241(5): 1950-1972, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38095236

RESUMO

Histone H3 lysine-4 trimethylation (H3K4me3) activating drought-responsive genes in plants for drought adaptation has long been established, but the underlying regulatory mechanisms are unknown. Here, using yeast two-hybrid, bimolecular fluorescence complementation, biochemical analyses, transient and CRISPR-mediated transgenesis in Populus trichocarpa, we unveiled in this adaptation a regulatory interplay between chromatin regulation and gene transactivation mediated by an epigenetic determinant, a PtrSDG2-1-PtrCOMPASS (complex proteins associated with Set1)-like H3K4me3 complex, PtrSDG2-1-PtrWDR5a-1-PtrRbBP5-1-PtrAsh2-2 (PtrSWRA). Under drought conditions, a transcription factor PtrAREB1-2 interacts with PtrSWRA, forming a PtrSWRA-PtrAREB1-2 pentamer, to recruit PtrSWRA to specific promoter elements of drought-tolerant genes, such as PtrHox2, PtrHox46, and PtrHox52, for depositing H3K4me3 to promote and maintain activated state of such genes for tolerance. CRISPR-edited defects in the pentamer impaired drought tolerance and elevated expression of PtrHox2, PtrHox46, or PtrHox52 improved the tolerance as well as growth in P. trichocarpa. Our findings revealed the identity of the underlying H3K4 trimethyltransferase and its interactive arrangement with the COMPASS for catalysis specificity and efficiency. Furthermore, our study uncovered how the H3K4 trimethyltransferase-COMPASS complex is recruited to the effector genes for elevating H3K4me3 marks for improved drought tolerance and growth/biomass production in plants.


Assuntos
Histonas , Populus , Histonas/metabolismo , Populus/metabolismo , Resistência à Seca , Biomassa , Cromatina , Saccharomyces cerevisiae/metabolismo
7.
Mol Plant ; 17(1): 112-140, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38102833

RESUMO

Cell walls in plants, particularly forest trees, are the major carbon sink of the terrestrial ecosystem. Chemical and biosynthetic features of plant cell walls were revealed early on, focusing mostly on herbaceous model species. Recent developments in genomics, transcriptomics, epigenomics, transgenesis, and associated analytical techniques are enabling novel insights into formation of woody cell walls. Here, we review multilevel regulation of cell wall biosynthesis in forest tree species. We highlight current approaches to engineering cell walls as potential feedstock for materials and energy and survey reported field tests of such engineered transgenic trees. We outline opportunities and challenges in future research to better understand cell type biogenesis for more efficient wood cell wall modification and utilization for biomaterials or for enhanced carbon capture and storage.


Assuntos
Lignina , Madeira , Madeira/genética , Madeira/metabolismo , Lignina/metabolismo , Ecossistema , Plantas/metabolismo , Parede Celular/metabolismo , Árvores/genética
8.
Science ; 381(6654): 216-221, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37440632

RESUMO

The domestication of forest trees for a more sustainable fiber bioeconomy has long been hindered by the complexity and plasticity of lignin, a biopolymer in wood that is recalcitrant to chemical and enzymatic degradation. Here, we show that multiplex CRISPR editing enables precise woody feedstock design for combinatorial improvement of lignin composition and wood properties. By assessing every possible combination of 69,123 multigenic editing strategies for 21 lignin biosynthesis genes, we deduced seven different genome editing strategies targeting the concurrent alteration of up to six genes and produced 174 edited poplar variants. CRISPR editing increased the wood carbohydrate-to-lignin ratio up to 228% that of wild type, leading to more-efficient fiber pulping. The edited wood alleviates a major fiber-production bottleneck regardless of changes in tree growth rate and could bring unprecedented operational efficiencies, bioeconomic opportunities, and environmental benefits.


Assuntos
Edição de Genes , Lignina , Populus , Madeira , Carboidratos/análise , Lignina/genética , Madeira/genética , Sistemas CRISPR-Cas , Populus/genética , Papel , Crescimento Sustentável
9.
Am J Transplant ; 23(8): 1227-1240, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37156300

RESUMO

Intracardiac thrombosis and/or pulmonary thromboembolism (ICT/PE) is a rare but devastating complication during liver transplantation. Its pathophysiology remains poorly understood, and successful treatment remains a challenge. This systematic review summarizes the available published clinical data regarding ICT/PE during liver transplantation. Databases were searched for all publications reporting on ICT/PE during liver transplantation. Data collected included its incidence, patient characteristics, the timing of diagnosis, treatment strategies, and patient outcomes. This review included 59 full-text citations. The point prevalence of ICT/PE was 1.42%. Thrombi were most often diagnosed during the neohepatic phase, particularly at allograft reperfusion. Intravenous heparin was effective in preventing early-stage thrombus from progressing further and restoring hemodynamics in 76.32% of patients it was utilized for; however, the addition of tissue plasminogen activator or sole use of tissue plasminogen activator offered diminishing returns. Despite all resuscitation efforts, the in-hospital mortality rate of an intraoperative ICT/PE was 40.42%, with nearly half of these patients dying intraoperatively. The results of our systematic review are an initial step for providing clinicians with data that can help identify higher-risk patients. The clinical implications of our results warrant the development of identification and management strategies for the timely and effective treatment of these tragic occurrences during liver transplantation.


Assuntos
Cardiopatias , Transplante de Fígado , Embolia Pulmonar , Trombose , Humanos , Ativador de Plasminogênio Tecidual , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Trombose/etiologia , Trombose/diagnóstico , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/tratamento farmacológico , Embolia Pulmonar/etiologia
10.
Mol Metab ; 71: 101712, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36963615

RESUMO

OBJECTIVE: In the fibrotic kidneys, the extent of a formed deleterious microenvironment is determined by cellular mechanical forces. This process requires metabolism for energy. However, how cellular mechanics and metabolism are connected remains unclear. METHODS: A multi-disciplinary approach was employed: the fibrotic kidney disease models were induced by renal ischemia-reperfusion injury and unilateral ureteral obstruction in Calponin 2 (CNN2) knockdown mice. Proteomics, bioinformatics, and in vivo and in vitro molecular experimental pathology studies were performed. RESULT: Our proteomics revealed that actin filament binding and cell metabolism are the two most dysregulated events in the fibrotic kidneys. As a prominent actin stabilizer, CNN2 was predominantly expressed in fibroblasts and pericytes. In CKD patients, CNN2 levels was markedly induced in blood. In mice, CNN2 knockdown preserves kidney function and alleviates fibrosis. Global proteomics profiled that CNN2 knockdown enhanced the activities of the key rate-limiting enzymes and regulators of fatty acid oxidation (FAO) in the diseased kidneys. Inhibiting carnitine palmitoyltransferase 1α in the FAO pathway resulted in lipid accumulation and extracellular matrix deposition in the fibrotic kidneys, which were restored after CNN2 knockdown. Bioinformatics and chromatin immunoprecipitation showed that CNN2 interactor, estrogen receptor 2 (ESR2), binds peroxisome proliferator-activated receptor-α (PPARα) to transcriptionally regulate FAO downstream target genes expression amid kidney fibrosis. In vitro, ESR2 knockdown repressed the mRNA levels of PPARα and the key genes in the FAO pathway. Conversely, activation of PPARα reduced CNN2-induced matrix inductions. CONCLUSIONS: Our results suggest that balancing cell mechanics and metabolism is crucial to develop therapeutic strategies to halt kidney fibrosis.


Assuntos
Proteínas de Ligação a Calmodulina , Nefropatias , Animais , Camundongos , Fibrose , Rim/metabolismo , Rim/patologia , Nefropatias/metabolismo , Nefropatias/patologia , PPAR alfa/metabolismo , Proteínas de Ligação a Calmodulina/metabolismo , Calponinas
11.
Nat Plants ; 9(1): 96-111, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36624255

RESUMO

Stem vascular cambium cells in forest trees produce wood for materials and energy. WOX4 affects the proliferation of such cells in Populus. Here we show that PtrWOX4a is the most highly expressed stem vascular-cambium-specific (VCS) gene in P. trichocarpa, and its expression is controlled by the product of the second most highly expressed VCS gene, PtrVCS2, encoding a zinc finger protein. PtrVCS2 binds to the PtrWOX4a promoter as part of a PtrWOX13a-PtrVCS2-PtrGCN5-1-PtrADA2b-3 protein tetramer. PtrVCS2 prevented the interaction between PtrGCN5-1 and PtrADA2b-3, resulting in H3K9, H3K14 and H3K27 hypoacetylation at the PtrWOX4a promoter, which led to fewer cambium cell layers. These effects on cambium cell proliferation were consistent across more than 20 sets of transgenic lines overexpressing individual genes, gene-edited mutants and RNA interference lines in P. trichocarpa. We propose that the tetramer-PtrWOX4a system may coordinate genetic and epigenetic regulation to maintain normal vascular cambium development for wood formation.


Assuntos
Câmbio , Populus , Câmbio/genética , Populus/genética , Epigênese Genética , Código das Histonas , Madeira , Regulação da Expressão Gênica de Plantas
12.
Bioresour Technol ; 367: 128275, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36347479

RESUMO

Naturally occurring, microbial contaminants were found in plant biomasses from common bioenergy crops and agricultural wastes. Unexpectedly, indigenous thermophilic microbes were abundant, raising the question of whether they impact thermophilic consolidated bioprocessing fermentations that convert biomass directly into useful bioproducts. Candidate microbial platforms for biomass conversion, Acetivibrio thermocellus (basionym Clostridium thermocellum; Topt 60 °C) and Caldicellulosiruptor bescii (Topt 78 °C), each degraded a wide variety of plant biomasses, but only A. thermocellus was significantly affected by the presence of indigenous microbial populations harbored by the biomass. Indigenous microbial growth was eliminated at ≥75 °C, conditions where C. bescii thrives, but where A. thermocellus cannot survive. Therefore, 75 °C is the thermophilic threshold to avoid sterilizing pre-treatments on the biomass that prevents native microbes from competing with engineered microbes and forming undesirable by-products. Thermophiles that naturally grow at and above 75 °C offer specific advantages as platform microorganisms for biomass conversion into fuels and chemicals.


Assuntos
Clostridium thermocellum , Lignina , Biomassa , Fermentação , Lignina/química , Clostridium thermocellum/metabolismo , Plantas/metabolismo
13.
World J Clin Cases ; 10(34): 12605-12609, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36579114

RESUMO

BACKGROUND: Cytomegalovirus (CMV) infection is usually subclinical and asymptomatic in the healthy population, whereas severe complications occur in immunocompromised patients. CASE SUMMARY: In this case report, we described a rare case of acute CMV hepatitis in a 35-year-old male immunocompetent patient who presented with a history of week-long intermittent fever with nonspecific constitutional symptoms. Acute hepatitis was suspected according to the initial serological tests. After ruling out other etiologies, including viral hepatitis A, B, C, drug, alcohol, autoimmune, and Wilson disease, acute CMV hepatitis was diagnosed based on positive CMV IgM and DNA quantitative tests. Because there was no any local acute hepatitis E reported in Taiwan, so hepatitis E was not checked. The patient recovered both clinically and serologically with symptomatic management and without antiviral therapy within 12 days from the onset of symptom. CONCLUSION: In conclusion, a diagnosis of CMV infection should be considered when nonspecific prodromal symptoms occur in acute hepatitis with an uncertain etiology. Antiviral therapy should not be used in immunocompetent patient who had no decompensation of the liver, such as this patient. Widely available noninvasive tests for CMV can facilitate early diagnosis if used appropriately. Harm-benefit analysis is essential before using antiviral therapy in immunocompetent patients.

14.
Cureus ; 14(10): e30474, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36415439

RESUMO

Polyarticular septic arthritis (PASA) is less common than monoarticular septic arthritis (MASA). There is a low incidence of PASA in immunocompetent patients. This case report describes the development of PASA after hemodialysis through the permcath after a single session.

15.
Front Plant Sci ; 13: 883421, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35592579

RESUMO

Gene-editing tools, such as Zinc-fingers, TALENs, and CRISPR-Cas, have fostered a new frontier in the genetic improvement of plants across the tree of life. In eukaryotes, genome editing occurs primarily through two DNA repair pathways: non-homologous end joining (NHEJ) and homologous recombination (HR). NHEJ is the primary mechanism in higher plants, but it is unpredictable and often results in undesired mutations, frameshift insertions, and deletions. Homology-directed repair (HDR), which proceeds through HR, is typically the preferred editing method by genetic engineers. HR-mediated gene editing can enable error-free editing by incorporating a sequence provided by a donor template. However, the low frequency of native HR in plants is a barrier to attaining efficient plant genome engineering. This review summarizes various strategies implemented to increase the frequency of HDR in plant cells. Such strategies include methods for targeting double-strand DNA breaks, optimizing donor sequences, altering plant DNA repair machinery, and environmental factors shown to influence HR frequency in plants. Through the use and further refinement of these methods, HR-based gene editing may one day be commonplace in plants, as it is in other systems.

16.
J Sci Educ Technol ; 31(3): 303-321, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35132301

RESUMO

As students transition into tertiary blended learning environments, their digital literacy in terms of technical capabilities have potential to impact on their access to digital resources. The first foundational year of STEM degrees includes compulsory courses across a broad range of scientific areas, each of which incorporates online technology in a discipline-specific manner. Given the diversity of online resources that STEM students need to access across their first-year coursework, this study applies learning analytical methods to determine whether students' perceived level of digital literacy has an effect on their navigation of learning management systems (LMS) and overall academic performance. The frequency and nature of LMS interactivity were examined across four first-year STEM courses offered in the same semester at a single institution, using a K-means cluster analysis to group student responses. It was observed that high achieving students accessed LMS resources more frequently than mid or low-achieving students across all four STEM courses. Students' perceived level of digital literacy was collected via survey (n = 282), and students were sorted high (n = 106) and low-level (n = 176) of perceived digital literacy-HDL and LDL, respectively. HDL students were not consistently found in the high-achieving academic group and did not perform better in their overall grade when compared to LDL students. LDL students were observed to perform better in specific online assessment tasks, which may be attributed to their increased frequency of LMS interactivity. These findings highlight the delicate balance between students' perceived level of digital literacy, motivation for engaging with online learning environments, and academic performance.

17.
New Phytol ; 234(3): 918-933, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35152419

RESUMO

Wood formation is controlled by transcriptional regulatory networks (TRNs) involving regulatory homeostasis determined by combinations of transcription factor (TF)-DNA and TF-TF interactions. Functions of TF-TF interactions in wood formation are still in the early stages of identification. PtrMYB074 is a woody dicot-specific TF in a TRN for wood formation in Populus trichocarpa. Here, using yeast two-hybrid and bimolecular fluorescence complementation, we conducted a genome-wide screening for PtrMYB074 interactors and identified 54 PtrMYB074-TF pairs. Of these pairs, 53 are novel. We focused on the PtrMYB074-PtrWRKY19 pair, the most highly expressed and xylem-specific interactor, and its direct transregulatory target, PtrbHLH186, the xylem-specific one of the pair's only two direct TF target genes. Using transient and CRISPR-mediated transgenesis in P. trichocarpa coupled with chromatin immunoprecipitation and electrophoretic mobility shift assays, we demonstrated that PtrMYB074 is recruited by PtrWRKY19 and that the PtrMYB074-PtrWRKY19 dimers are required to transactive PtrbHLH186. Overexpressing PtrbHLH186 in P. trichocarpa resulted in retarded plant growth, increased guaiacyl lignin, a higher proportion of smaller stem vessels and strong drought-tolerant phenotypes. Knowledge of the PtrMYB074-PtrWRKY19-PtrbHLH186 regulation may help design genetic controls of optimal growth and wood formation to maximize beneficial wood properties while minimizing negative effects on growth.


Assuntos
Populus , Parede Celular/metabolismo , Dimerização , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ativação Transcricional , Madeira , Xilema/metabolismo
18.
Bioresour Technol ; 348: 126780, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35093526

RESUMO

A variety of chemical and biological processes have been proposed for conversion of sustainable low-cost feedstocks into industrial products. Here, a biorefinery concept is formulated, modeled, and analyzed in which a naturally (hemi)cellulolytic and extremely thermophilic bacterium, Caldicellulosiruptor bescii, is metabolically engineered to convert the carbohydrate content of lignocellulosic biomasses (i.e., soybean hulls, transgenic poplar) into green hydrogen and acetone. Experimental validation of C. bescii fermentative performance demonstrated 82% carbohydrate solubilization of soybean hulls and 55% for transgenic poplar. A detailed technical design, including equipment specifications, provides the basis for an economic analysis that establishes metabolic engineering targets. This robust industrial process leveraging metabolically engineered C. bescii yields 206 kg acetone and 25 kg H2 per metric ton of soybean hull, or 174 kg acetone and 21 kg H2 per metric ton transgenic poplar. Beyond this specific case, the model demonstrates industrial feasibility and economic advantages of thermophilic fermentation.


Assuntos
Acetona , Lignina , Biomassa , Caldicellulosiruptor , Fermentação , Hidrogênio , Lignina/química
19.
Plant Commun ; 3(1): 100250, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35059630

RESUMO

Tension wood (TW) is a specialized xylem tissue formed in angiosperm trees under gravitational stimulus or mechanical stresses (e.g., bending). The genetic regulation that underlies this important mechanism remains poorly understood. Here, we used laser capture microdissection of stem xylem cells coupled with full transcriptome RNA-sequencing to analyze TW formation in Populus trichocarpa. After tree bending, PtrLBD39 was the most significantly induced transcription factor gene; it has a phylogenetically paired homolog, PtrLBD22. CRISPR-based knockout of PtrLBD39/22 severely inhibited TW formation, reducing cellulose and increasing lignin content. Transcriptomic analyses of CRISPR-based PtrLBD39/22 double mutants showed that these two genes regulate a set of TW-related genes. Chromatin immunoprecipitation sequencing (ChIP-seq) was used to identify direct targets of PtrLBD39. We integrated transcriptomic analyses and ChIP-seq assays to construct a transcriptional regulatory network (TRN) mediated by PtrLBD39. In this TRN, PtrLBD39 directly regulates 26 novel TW-responsive transcription factor genes. Our work suggests that PtrLBD39 and PtrLBD22 specifically control TW formation by mediating a TW-specific TRN in Populus.


Assuntos
Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Genes de Plantas , Populus , Madeira , Fenômenos Biomecânicos , Regulação da Expressão Gênica de Plantas/fisiologia , Redes Reguladoras de Genes/fisiologia , Genes de Plantas/genética , Genes de Plantas/fisiologia , Microdissecção e Captura a Laser , Populus/genética , Populus/fisiologia , Madeira/genética , Madeira/fisiologia , Xilema
20.
Artigo em Inglês | MEDLINE | ID: mdl-34635549

RESUMO

BACKGROUND: This study investigated the association between socioeconomic status and type 2 diabetes (T2D) prevalence in Scotland in 2021 and tested the null hypothesis that inequalities had not changed since they were last described for 2001-2007. METHODS: Data from a national population-based diabetes database for 35-to-84-year-olds in Scotland for 2021 and mid-year population estimates for 2019 stratified by sex and fifths of the Scottish Index of Multiple Deprivation were used to calculate age-specific prevalence of T2D. Age-standardised prevalence was estimated using the European Standard Population with relative risks (RRs) compared between the most (Q1) and least (Q5) deprived fifths for each sex, and compared against similar estimates from 2001 to 2007. RESULTS: Complete data were available for 255 764 people (98.9%) with T2D. Age-standardised prevalence was lowest for women in Q5 (3.4%) and highest for men in Q1 (11.6%). RRs have increased from 2.00 (95% CI 1.52 to 2.62) in 2001-2007 to 2.48 (95% CI 2.43 to 2.53) in 2021 for women and from 1.58 (95% CI 1.20 to 2.07) in 2007 to 1.89 (95% CI 1.86 to 1.92) in 2021 for men. CONCLUSIONS: Socioeconomic inequalities in T2D prevalence have widened between 2001-2007 and 2021. Further research is required to investigate potential medium-term effects of the COVID-19 pandemic.

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