Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71
Filtrar
1.
Commun Biol ; 7(1): 172, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38347116

RESUMEN

The capacity to leverage high resolution mass spectrometry (HRMS) with transient isotope labeling experiments is an untapped opportunity to derive insights on context-specific metabolism, that is difficult to assess quantitatively. Tools are needed to comprehensively mine isotopologue information in an automated, high-throughput way without errors. We describe a tool, Stable Isotope-assisted Metabolomics for Pathway Elucidation (SIMPEL), to simplify analysis and interpretation of isotope-enriched HRMS datasets. The efficacy of SIMPEL is demonstrated through examples of central carbon and lipid metabolism. In the first description, a dual-isotope labeling experiment is paired with SIMPEL and isotopically nonstationary metabolic flux analysis (INST-MFA) to resolve fluxes in central metabolism that would be otherwise challenging to quantify. In the second example, SIMPEL was paired with HRMS-based lipidomics data to describe lipid metabolism based on a single labeling experiment. Available as an R package, SIMPEL extends metabolomics analyses to include isotopologue signatures necessary to quantify metabolic flux.


Asunto(s)
Carbono , Metabolómica , Isótopos de Carbono/química , Espectrometría de Masas/métodos , Metabolómica/métodos
2.
Bioinformatics ; 39(11)2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37889279

RESUMEN

SUMMARY: The analysis of stable isotope labeling experiments requires accurate, efficient, and reproducible quantification of mass isotopomer distributions (MIDs), which is not a core feature of general-purpose metabolomics software tools that are optimized to quantify metabolite abundance. Here, we present PIRAMID (Program for Integration and Rapid Analysis of Mass Isotopomer Distributions), a MATLAB-based tool that addresses this need by offering a user-friendly, graphical user interface-driven program to automate the extraction of isotopic information from mass spectrometry (MS) datasets. This tool can simultaneously extract ion chromatograms for various metabolites from multiple data files in common vendor-agnostic file formats, locate chromatographic peaks based on a targeted list of characteristic ions and retention times, and integrate MIDs for each target ion. These MIDs can be corrected for natural isotopic background based on the user-defined molecular formula of each ion. PIRAMID offers support for datasets acquired from low- or high-resolution MS, and single (MS) or tandem (MS/MS) instruments. It also enables the analysis of single or dual labeling experiments using a variety of isotopes (i.e. 2H, 13C, 15N, 18O, 34S). DATA AVAILABILITY AND IMPLEMENTATION: MATLAB p-code files are freely available for non-commercial use and can be downloaded from https://mfa.vueinnovations.com/. Commercial licenses are also available. All the data presented in this publication are available under the "Help_menu" folder of the PIRAMID software.


Asunto(s)
Programas Informáticos , Espectrometría de Masas en Tándem , Isótopos de Oxígeno , Metabolómica/métodos
3.
Sensors (Basel) ; 23(20)2023 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-37896715

RESUMEN

Hyperspectral imagers, or imaging spectrometers, are used in many remote sensing environmental studies in fields such as agriculture, forestry, geology, and hydrology. In recent years, compact hyperspectral imagers were developed using commercial-off-the-shelf components, but there are not yet any off-the-shelf data acquisition systems on the market to deploy them. The lack of a self-contained data acquisition system with navigation sensors is a challenge that needs to be overcome to successfully deploy these sensors on remote platforms such as drones and aircraft. Our work is the first successful attempt to deploy an entirely open-source system that is able to collect hyperspectral and navigation data concurrently for direct georeferencing. In this paper, we describe a low-cost, lightweight, and deployable data acquisition device for the open-source hyperspectral imager (OpenHSI). We utilised commercial-off-the-shelf hardware and open-source software to create a compact data acquisition device that can be easily transported and deployed. The device includes a microcontroller and a custom-designed PCB board to interface with ancillary sensors and a Raspberry Pi 4B/NVIDIA Jetson. We demonstrated our data acquisition system on a Matrice M600 drone at a beach in Sydney, Australia, collecting timestamped hyperspectral, navigation, and orientation data in parallel. Using the navigation and orientation data, the hyperspectral data were georeferenced. While the entire system including the pushbroom hyperspectral imager and housing weighed 735 g, it was designed to be easy to assemble and modify. This low-cost, customisable, deployable data acquisition system provides a cost-effective solution for the remote sensing of hyperspectral data for everyone.

4.
Plant Physiol ; 192(3): 2436-2456, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37017001

RESUMEN

Many molecular and physiological processes in plants occur at a specific time of day. These daily rhythms are coordinated in part by the circadian clock, a timekeeper that uses daylength and temperature to maintain rhythms of ∼24 h in various clock-regulated phenotypes. The circadian MYB-like transcription factor REVEILLE 8 (RVE8) interacts with its transcriptional coactivators NIGHT LIGHT-INDUCIBLE AND CLOCK-REGULATED 1 (LNK1) and LNK2 to promote the expression of evening-phased clock genes and cold tolerance factors. While genetic approaches have commonly been used to discover connections within the clock and between clock elements and other pathways, here, we used affinity purification coupled with mass spectrometry (APMS) to identify time-of-day-specific protein interactors of the RVE8-LNK1/LNK2 complex in Arabidopsis (Arabidopsis thaliana). Among the interactors of RVE8/LNK1/LNK2 were COLD-REGULATED GENE 27 (COR27) and COR28, which coprecipitated in an evening-specific manner. In addition to COR27 and COR28, we found an enrichment of temperature-related interactors that led us to establish a previously uncharacterized role for LNK1 and LNK2 in temperature entrainment of the clock. We established that RVE8, LNK1, and either COR27 or COR28 form a tripartite complex in yeast (Saccharomyces cerevisiae) and that the effect of this interaction in planta serves to antagonize transcriptional activation of RVE8 target genes, potentially through mediating RVE8 protein degradation in the evening. Together, these results illustrate how a proteomic approach can be used to identify time-of-day-specific protein interactions. Discovery of the RVE8-LNK-COR protein complex indicates a previously unknown regulatory mechanism for circadian and temperature signaling pathways.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Relojes Circadianos , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteómica , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Arabidopsis/metabolismo , Relojes Circadianos/genética , Ritmo Circadiano/genética , Regulación de la Expresión Génica de las Plantas , Proteínas Represoras/metabolismo
5.
Nat Genet ; 55(4): 631-639, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36973455

RESUMEN

Cryptic promoters within transposable elements (TEs) can be transcriptionally reactivated in tumors to create new TE-chimeric transcripts, which can produce immunogenic antigens. We performed a comprehensive screen for these TE exaptation events in 33 TCGA tumor types, 30 GTEx adult tissues and 675 cancer cell lines, and identified 1,068 TE-exapted candidates with the potential to generate shared tumor-specific TE-chimeric antigens (TS-TEAs). Whole-lysate and HLA-pulldown mass spectrometry data confirmed that TS-TEAs are presented on the surface of cancer cells. In addition, we highlight tumor-specific membrane proteins transcribed from TE promoters that constitute aberrant epitopes on the extracellular surface of cancer cells. Altogether, we showcase the high pan-cancer prevalence of TS-TEAs and atypical membrane proteins that could potentially be therapeutically exploited and targeted.


Asunto(s)
Elementos Transponibles de ADN , Neoplasias , Adulto , Humanos , Elementos Transponibles de ADN/genética , Antígenos de Neoplasias/genética , Regiones Promotoras Genéticas/genética , Neoplasias/genética , Línea Celular
6.
Surg Endosc ; 37(7): 5236-5240, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36952047

RESUMEN

BACKGROUND: Prophylactic ursodeoxycholic acid (UDCA) may be beneficial in reducing gallstone disease after bariatric surgery. The American Society for Metabolic and Bariatric Surgery (ASMBS) 2019 guidelines recommend a 6-month course of UDCA for patients undergoing laparoscopic sleeve gastrectomy (LSG). This has not been adopted broadly. This study intends to assess the effect of routine UDCA administration following LSG on symptomatic gallstone disease. METHODS: We performed a retrospective chart review of patients who underwent LSG, between 2009 and 2019, at two tertiary care centers in Atlantic Canada. At one center, UDCA 250 mg oral twice daily was routinely prescribed following LSG for 6 months to patients with an intact gallbladder. At the other center, UDCA was not prescribed. Primary and secondary outcomes were cholecystectomy and endoscopic retrograde cholangiopancreatography (ERCP) rates. Compliance with and side effects of UDCA therapy were analyzed. RESULTS: A total of 751 patients were included in the study. Patients who had prior cholecystectomy or were lost to follow up were excluded. After exclusion criteria were applied, 461 patients were included for analysis: 303 in the UDCA group and 158 in the group who did not receive UDCA. Cholecystectomy rate was not significantly associated with UDCA administration, however there was a trend towards less cholecystectomy in patients who received UDCA (8.3% vs. 13.9%, p = 0.056). ERCP rate was significantly lower in patients who received UDCA (0.3% vs 2.5%, p = 0.031). Rate of gallstone disease requiring intervention, either cholecystectomy or ERCP, was significantly decreased in patients who received UDCA (8.9% vs 15.8%, p = 0.022). The most common barriers to compliance with UDCA were cost (45.4%) and nausea (18.1%). CONCLUSION: This is the first study to demonstrate lower rates of ERCP in patients receiving routine UDCA following LSG. Our findings support the ASMBS 2019 guidelines for administering UDCA after LSG for preventing gallstone disease.


Asunto(s)
Cálculos Biliares , Gastrectomía , Ácido Ursodesoxicólico , Humanos , Cálculos Biliares/etiología , Cálculos Biliares/prevención & control , Cálculos Biliares/cirugía , Gastrectomía/efectos adversos , Laparoscopía/efectos adversos , Obesidad Mórbida/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos , Ácido Ursodesoxicólico/uso terapéutico
7.
bioRxiv ; 2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36778509

RESUMEN

Untargeted lipidomics allows analysis of a broader range of lipids than targeted methods and permits discovery of unknown compounds. Previous ring trials have evaluated the reproducibility of targeted lipidomics methods, but inter-laboratory comparison of compound identification and unknown feature detection in untargeted lipidomics has not been attempted. To address this gap, five laboratories analyzed a set of mammalian tissue and biofluid reference samples using both their own untargeted lipidomics procedures and a common chromatographic and data analysis method. While both methods yielded informative data, the common method improved chromatographic reproducibility and resulted in detection of more shared features between labs. Spectral search against the LipidBlast in silico library enabled identification of over 2,000 unique lipids. Further examination of LC-MS/MS and ion mobility data, aided by hybrid search and spectral networking analysis, revealed spectral and chromatographic patterns useful for classification of unknown features, a subset of which were highly reproducible between labs. Overall, our method offers enhanced compound identification performance compared to targeted lipidomics, demonstrates the potential of harmonized methods to improve inter-site reproducibility for quantitation and feature alignment, and can serve as a reference to aid future annotation of untargeted lipidomics data.

8.
Cell Rep ; 40(9): 111300, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-35988540

RESUMEN

Synthetic mRNA technology is a promising avenue for treating and preventing disease. Key to the technology is the incorporation of modified nucleotides such as N1-methylpseudouridine (m1Ψ) to decrease immunogenicity of the RNA. However, relatively few studies have addressed the effects of modified nucleotides on the decoding process. Here, we investigate the effect of m1Ψ and the related modification pseudouridine (Ψ) on translation. In a reconstituted system, we find that m1Ψ does not significantly alter decoding accuracy. More importantly, we do not detect an increase in miscoded peptides when mRNA containing m1Ψ is translated in cell culture, compared with unmodified mRNA. We also find that m1Ψ does not stabilize mismatched RNA-duplex formation and only marginally promotes errors during reverse transcription. Overall, our results suggest that m1Ψ does not significantly impact translational fidelity, a welcome sign for future RNA therapeutics.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , COVID-19/prevención & control , Humanos , Nucleótidos , Proteínas , Seudouridina/genética , ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo , Vacunas Sintéticas , Vacunas de ARNm
9.
BMC Genomics ; 23(1): 413, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35650521

RESUMEN

BACKGROUND: Despite sexual development being ubiquitous to vertebrates, the molecular mechanisms underpinning this fundamental transition remain largely undocumented in many organisms. We designed a time course experiment that successfully sampled the period when Atlantic salmon commence their trajectory towards sexual maturation. RESULTS: Through deep RNA sequencing, we discovered key genes and pathways associated with maturation in the pituitary-ovarian axis. Analyzing DNA methylomes revealed a bias towards hypermethylation in ovary that implicated maturation-related genes. Co-analysis of DNA methylome and gene expression changes revealed chromatin remodeling genes and key transcription factors were both significantly hypermethylated and upregulated in the ovary during the onset of maturation. We also observed changes in chromatin state landscapes that were strongly correlated with fundamental remodeling of gene expression in liver. Finally, a multiomic integrated analysis revealed regulatory networks and identified hub genes including TRIM25 gene (encoding the estrogen-responsive finger protein) as a putative key regulator in the pituitary that underwent a 60-fold change in connectivity during the transition to maturation. CONCLUSION: The study successfully documented transcriptome and epigenome changes that involved key genes and pathways acting in the pituitary - ovarian axis. Using a Systems Biology approach, we identified hub genes and their associated networks deemed crucial for onset of maturation. The results provide a comprehensive view of the spatiotemporal changes involved in a complex trait and opens the door to future efforts aiming to manipulate puberty in an economically important aquaculture species.


Asunto(s)
Epigenoma , Transcriptoma , Animales , Femenino , Ovario/metabolismo , Análisis de Secuencia de ARN/métodos , Maduración Sexual/genética
10.
Evol Appl ; 15(4): 631-644, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35505884

RESUMEN

Genomic information was included for the first time in the prediction of breeding values for Atlantic salmon within the Australian Salmon Enterprises of Tasmania Pty Ltd selective breeding program in 2016. The process to realize genomic selection in the breeding program begun in 2014 with the scheme finalized and fully implemented for the first time in 2018. The high potential of within family selection to accelerate genetic gain, something not possible using the traditional pedigree-based approach, provided the impetus for implementation. Efficient and effective genotyping platforms are essential for genomic selection. Genotype data from high density arrays revealed extensive persistence of linkage disequilibrium in the Tasmania Atlantic salmon population, resulting in high accuracies of both imputation and genomic breeding values when using imputed data. Consequently, a low-density novel genotype-by-sequence assay was designed and incorporated into the scheme. Through the use of a static high- and dynamic low-density genotyping platforms, an optimized genotyping scheme was devised and implemented such that all individuals in every year class are genotyped efficiently while maximizing the genetic gains and minimizing costs. The increase in the rates of genetic gain attributed to the implementation of genomic selection is significant across both the breeding programs primary and secondary traits. Substantial improvement in the ability to select parents prior to progeny testing is observed across multiple years. The resultant economic impacts for the industry are considerable based on the increases in genetic gain for traits achieved within the breeding program and the use of genomic selection for commercial production.

11.
Commun Biol ; 5(1): 460, 2022 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-35562408

RESUMEN

Different intensities of high temperatures affect the growth of photosynthetic cells in nature. To elucidate the underlying mechanisms, we cultivated the unicellular green alga Chlamydomonas reinhardtii under highly controlled photobioreactor conditions and revealed systems-wide shared and unique responses to 24-hour moderate (35°C) and acute (40°C) high temperatures and subsequent recovery at 25°C. We identified previously overlooked unique elements in response to moderate high temperature. Heat at 35°C transiently arrested the cell cycle followed by partial synchronization, up-regulated transcripts/proteins involved in gluconeogenesis/glyoxylate-cycle for carbon uptake and promoted growth. But 40°C disrupted cell division and growth. Both high temperatures induced photoprotection, while 40°C distorted thylakoid/pyrenoid ultrastructure, affected the carbon concentrating mechanism, and decreased photosynthetic efficiency. We demonstrated increased transcript/protein correlation during both heat treatments and hypothesize reduced post-transcriptional regulation during heat may help efficiently coordinate thermotolerance mechanisms. During recovery after both heat treatments, especially 40°C, transcripts/proteins related to DNA synthesis increased while those involved in photosynthetic light reactions decreased. We propose down-regulating photosynthetic light reactions during DNA replication benefits cell cycle resumption by reducing ROS production. Our results provide potential targets to increase thermotolerance in algae and crops.


Asunto(s)
Chlamydomonas reinhardtii , Carbono/metabolismo , Chlamydomonas reinhardtii/genética , Calor , Plantas/metabolismo , Temperatura , Tilacoides/metabolismo
12.
Nutrients ; 14(6)2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35334939

RESUMEN

Previous studies on capsaicin, the bioactive compound in chili peppers, have shown that it may have a beneficial effect in vivo when part of a regular diet. These positive health benefits, including an anti-inflammatory potential and protective effects against obesity, are often attributed to the gut microbial community response to capsaicin. However, there is no consensus on the mechanism behind the protective effect of capsaicin. In this study, we used an in vitro model of the human gut microbiota to determine how regular consumption of capsaicin impacts the gut microbiota. Using a combination of NextGen sequencing and metabolomics, we found that regular capsaicin treatment changed the structure of the gut microbial community by increasing diversity and certain SCFA abundances, particularly butanoic acid. Through this study, we determined that the addition of capsaicin to the in vitro cultures of the human gut microbiome resulted in increased diversity of the microbial community and an increase in butanoic acid. These changes may be responsible for the health benefits associated with CAP consumption.


Asunto(s)
Microbioma Gastrointestinal , Capsaicina/farmacología , Dieta , Microbioma Gastrointestinal/fisiología , Humanos , Obesidad
13.
J Gastrointest Surg ; 26(7): 1388-1393, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35211834

RESUMEN

BACKGROUND: There are limited prospective data, and conflicting retrospective data, providing guidance on how to optimally manage patients with morbid obesity and severe knee osteoarthritis. This study sought to review the effect of bariatric surgery on knee pain and knee surgery 30-day outcomes, as well as assess whether the sequence of bariatric and knee surgery has any effect on 30-day complications. METHODS: A retrospective chart review of all patients undergoing laparoscopic sleeve gastrectomy (LSG) from July 2006 to July 2016 at a university hospital was performed. Patients with knee pain or knee surgery (pre- or post-LSG) were identified using bariatric and orthopedic clinic notes. Those who had improvement in knee pain following LSG resulting in removal from orthopedic surgery waitlist were identified. We also assessed surgical outcomes in patients undergoing knee arthroscopy or total knee arthroplasty (TKA) followed by LSG compared to patients undergoing LSG followed by knee arthroscopy or TKA. RESULTS: During our study timeframe, 355 patients underwent LSG. Knee pain was documented in 150 (42.2%) patients, and orthopedic surgery consultation was completed for 57 (38.0%) patients with knee pain. Orthopedic intervention was performed prior to LSG for 24 patients and after LSG for 27 patients. Procedures were a combination of arthroscopy (18) and TKA (33). Six patients were removed from the waitlist for TKA following LSG due to resolution of symptoms. Order of interventions did not affect 30-day complications for patients undergoing LSG and arthroscopy (16% arthroscopy first, 0% LSG first, p = 0.43). A higher rate of LSG complications was noted in patients who underwent TKA prior to LSG (25% vs 0%, p = 0.04). There were no differences in TKA complications (8.3% TKA first, 4.8% LSG first, p = 1.00). CONCLUSION: In a small number of patients with morbid obesity and severe knee osteoarthritis, orthopedic intervention can be delayed and potentially avoided by undergoing LSG. In our study, 6/57 (10.5%) of patients with orthopedic consultation prior to LSG saw resolution of symptoms of knee pain. Referral to bariatric surgery should be considered for patients with morbid obesity and severe knee osteoarthritis.


Asunto(s)
Cirugía Bariátrica , Laparoscopía , Obesidad Mórbida , Osteoartritis de la Rodilla , Cirugía Bariátrica/efectos adversos , Gastrectomía/métodos , Humanos , Laparoscopía/métodos , Obesidad Mórbida/complicaciones , Obesidad Mórbida/cirugía , Osteoartritis de la Rodilla/complicaciones , Osteoartritis de la Rodilla/cirugía , Dolor/etiología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Estudios Prospectivos , Estudios Retrospectivos , Resultado del Tratamiento , Pérdida de Peso
14.
Surg Endosc ; 36(7): 5392-5397, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34750703

RESUMEN

PURPOSE: To examine local practice for non-malignant polyps and to calculate morbidity and mortality associated with bowel resection for this indication. METHODS: This retrospective cohort study was conducted by reviewing our local gastrointestinal pathology database over a five-year period to identify colonic resections performed for benign polyps. Using search terms "polyp" and "adenoma," 272 cases were identified. Exclusion criteria included: cancer diagnosis, emergency surgeries, multiple resections, and subtotal colectomies for polyposis. 106 patients were included in the study. Primary outcome was perioperative mortality. Secondary outcomes included patient morbidity, characteristics of polyps requiring surgery, and the number of patients referred for a second endoscopic opinion prior to proceeding with surgery. RESULTS: 64 male and 42 female patients with a mean age of 65.3 years (± 8.6 years) underwent colon resection for benign polyps. The mean polyp size was 32.7 mm (± 19.5 mm). 30 patients (28.6%) had polyps equal to or less than 2 cm. Most of the polyps described were sessile (n = 55, 51.9%) and located in the right colon (n = 84, 79.3%). Endoscopic resection was attempted in 31 patients (29.2%), and five cases (4.7%) were referred for a second endoscopic opinion prior to proceeding with surgery. Endoscopists incorrectly felt that polyps were malignant in 62 cases (58.5%). Using Clavien-Dindo classification, most patients had no complications n = 36 (34.0%) or minor complications n = 41 (38.7%). Twelve patients (11.3%) had complications that required antibiotics, blood transfusions, or total parental nutrition. Nine patients (8.5%) required surgical or endoscopic management. Six patients (5.7%) required ICU admission. Mortality rate was 1.9% (n = 2). CONCLUSION: Surgery for benign colonic polyps is associated with significant morbidity and mortality. These findings reveal a gap in endoscopic management of benign colonic polyps.


Asunto(s)
Adenoma , Neoplasias del Colon , Pólipos del Colon , Adenoma/cirugía , Anciano , Colectomía/efectos adversos , Neoplasias del Colon/patología , Neoplasias del Colon/cirugía , Pólipos del Colon/diagnóstico , Colonoscopía/efectos adversos , Femenino , Humanos , Masculino , Estudios Retrospectivos
15.
J Am Soc Mass Spectrom ; 32(7): 1671-1688, 2021 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-34165968

RESUMEN

We present an updated analysis of the linker and core histone proteins and their proteoforms in the green microalga Chlamydomonas reinhardtii by top-down mass spectrometry (TDMS). The combination of high-resolution liquid chromatographic separation, robust fragmentation, high mass spectral resolution, the application of a custom search algorithm, and extensive manual analysis enabled the characterization of 86 proteoforms across all four core histones H2A, H2B, H3, and H4 and the linker histone H1. All canonical H2A paralogs, which vary in their C-termini, were identified, along with the previously unreported noncanonical variant H2A.Z that had high levels of acetylation and C-terminal truncations. Similarly, a majority of the canonical H2B paralogs were identified, along with a smaller noncanonical variant, H2B.v1, that was highly acetylated. Histone H4 exhibited a novel acetylation profile that differs significantly from that found in other organisms. A majority of H3 was monomethylated at K4 with low levels of co-occuring acetylation, while a small fraction of H3 was trimethylated at K4 with high levels of co-occuring acetylation.


Asunto(s)
Proteínas Algáceas , Chlamydomonas reinhardtii/química , Histonas , Espectrometría de Masas/métodos , Acetilación , Proteínas Algáceas/análisis , Proteínas Algáceas/química , Células Cultivadas , Histonas/análisis , Histonas/química , Procesamiento Proteico-Postraduccional
16.
Methods Mol Biol ; 2295: 219-247, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34047980

RESUMEN

The fatty acid biosynthetic cycle is predicated on an acyl carrier protein (ACP) scaffold where two carbon acetyl groups are added in a chain elongation process through a series of repeated enzymatic steps. The chain extension is terminated by hydrolysis with a thioesterase or direct transfer of the acyl group to a glycerophospholipid by an acyltransferase. Methods for analysis of the concentrations of acyl chains attached to ACPs are lacking but would be informative for studies in lipid metabolism. We describe a method to profile and quantify the levels of acyl-ACPs in plants, bacteria and mitochondria of animals and fungi that represent Type II fatty acid biosynthetic systems. ACPs of Type II systems have a highly conserved Asp-Ser-Leu-Asp (DSLD) amino acid sequence at the attachment site for 4'-phosphopantetheinyl arm carrying the acyl chain. Three amino acids of the conserved sequence can be cleaved away from the remainder of the protein using an aspartyl protease. Thus, partially purified protein can be enzymatically hydrolyzed to produce an acyl chain linked to a tripeptide via the 4'-phosphopantetheinyl group. After ionization and fragmentation, the corresponding fragment ion is detected by a triple quadrupole mass spectrometer using a multiple reaction monitoring method. 15N isotopically labeled acyl-ACPs generated in high amounts are used with an isotope dilution strategy to quantify the absolute levels of each acyl group attached to the acyl carrier protein scaffold.


Asunto(s)
Proteína Transportadora de Acilo/análisis , Proteína Transportadora de Acilo/aislamiento & purificación , Cromatografía Liquida/métodos , Proteína Transportadora de Acilo/metabolismo , Acilcoenzima A/metabolismo , Secuencia de Aminoácidos/genética , Bacterias/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Secuencia Conservada/genética , Ácidos Grasos/metabolismo , Metabolismo de los Lípidos/genética , Lípidos/química , Lipogénesis/genética , Mitocondrias/metabolismo , Plantas/metabolismo , Espectrometría de Masas en Tándem/métodos
17.
Mol Cell Proteomics ; 20: 100063, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33677124

RESUMEN

Protein phosphorylation is one of the most prevalent posttranslational modifications found in eukaryotic systems. It serves as a key molecular mechanism that regulates protein function in response to environmental stimuli. The Mut9-like kinases (MLKs) are a plant-specific family of Ser/Thr kinases linked to light, circadian, and abiotic stress signaling. Here we use quantitative phosphoproteomics in conjunction with global proteomic analysis to explore the role of the MLKs in daily protein dynamics. Proteins involved in light, circadian, and hormone signaling, as well as several chromatin-modifying enzymes and DNA damage response factors, were found to have altered phosphorylation profiles in the absence of MLK family kinases. In addition to altered phosphorylation levels, mlk mutant seedlings have an increase in glucosinolate metabolism enzymes. Subsequently, we show that a functional consequence of the changes to the proteome and phosphoproteome in mlk mutant plants is elevated glucosinolate accumulation and increased sensitivity to DNA damaging agents. Combined with previous reports, this work supports the involvement of MLKs in a diverse set of stress responses and developmental processes, suggesting that the MLKs serve as key regulators linking environmental inputs to developmental outputs.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Fosfoproteínas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas de Arabidopsis/genética , Daño del ADN , Redes y Vías Metabólicas , Mutación , Fosfoproteínas/genética , Proteínas Serina-Treonina Quinasas/genética , Proteómica , Transducción de Señal , Estrés Fisiológico
18.
Cureus ; 12(8): e9544, 2020 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-32905507

RESUMEN

Miscommunication during patient handover can be a major cause of preventable medical errors. Emergency traumas are situations where high stress and cognitive load make communication more difficult. Simulation allows for junior learners to practice emergency scenarios in a low-risk setting. This technical report outlines a simulation involving patient handover in emergency trauma scenarios. The intended group of learners are first-year surgery and emergency medicine residents. The scenarios were developed based on the learning objectives of communication, collaboration, and information transfer. Using a high-fidelity simulation mimicking a tertiary care facility, the skills performed in these scenarios can be applied to everyday practice.

20.
Front Genet ; 11: 264, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32318091

RESUMEN

The introduction of wild Atlantic salmon into captivity, and their subsequent artificial selection for production traits, has caused phenotypic differences between domesticated fish and their wild counterparts. Identification of regions of the genome underling these changes offers the promise of characterizing the early biological consequences of domestication. In the current study, we sequenced a population of farmed European Atlantic salmon and compared the observed patterns of SNP variation to those found in conspecific wild populations. This identified 139 genomic regions that contained significantly elevated SNP homozygosity in farmed fish when compared to their wild counterparts. The most extreme was adjacent to versican, a gene involved in control of neural crest cell migration. To control for false positive signals, a second and independent dataset of farmed and wild European Atlantic salmon was assessed using the same methodology. A total of 81 outlier regions detected in the first dataset showed significantly reduced homozygosity within the second one, strongly suggesting the genomic regions identified are enriched for true selection sweeps. Examination of the associated genes identified a number previously characterized as targets of selection in other domestic species and that have roles in development, behavior and olfactory system. These include arcvf, sema6, errb4, id2-like, and 6n1-like genes. Finally, we searched for evidence of parallel sweeps using a farmed population of North American origin. This failed to detect a convincing overlap to the putative sweeps present in European populations, suggesting the factors that drive patterns of variation under domestication and early artificial selection were largely independent. This is the first analysis on domestication of aquaculture species exploiting whole-genome sequence data and resulted in the identification of sweeps common to multiple independent populations of farmed European Atlantic salmon.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...