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1.
Brief Bioinform ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38385875

RESUMEN

Metabolomics and foodomics shed light on the molecular processes within living organisms and the complex food composition by leveraging sophisticated analytical techniques to systematically analyze the vast array of molecular features. The traditional feature-picking method often results in arbitrary selections of the model, feature ranking, and cut-off, which may lead to suboptimal results. Thus, a Multiple and Optimal Screening Subset (MOSS) approach was developed in this study to achieve a balance between a minimal number of predictors and high predictive accuracy during statistical model setup. The MOSS approach compares five commonly used models in the context of food matrix analysis, specifically bourbons. These models include Student's t-test, receiver operating characteristic curve, partial least squares-discriminant analysis (PLS-DA), random forests, and support vector machines. The approach employs cross-validation to identify promising subset feature candidates that contribute to food characteristic classification. It then determines the optimal subset size by comparing it to the corresponding top-ranked features. Finally, it selects the optimal feature subset by traversing all possible feature candidate combinations. By utilizing MOSS approach to analyze 1406 mass spectral features from a collection of 122 bourbon samples, we were able to generate a subset of features for bourbon age prediction with 88% accuracy. Additionally, MOSS increased the area under the curve performance of sweetness prediction to 0.898 with only four predictors compared with the top-ranked four features at 0.681 based on the PLS-DA model. Overall, we demonstrated that MOSS provides an efficient and effective approach for selecting optimal features compared with other frequently utilized methods.


Asunto(s)
Metabolómica , Proyectos de Investigación , Análisis Discriminante , Modelos Estadísticos , Curva ROC
2.
Blood ; 143(11): 1018-1031, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38127913

RESUMEN

ABSTRACT: Disordered erythropoiesis is a feature of many hematologic diseases, including sickle cell disease (SCD). However, very little is known about erythropoiesis in SCD. Here, we show that although bone marrow (BM) erythroid progenitors and erythroblasts in Hbbth3/+ thalassemia mice were increased more than twofold, they were expanded by only ∼40% in Townes sickle mice (SS). We further show that the colony-forming ability of SS erythroid progenitors was decreased and erythropoietin (EPO)/EPO receptor (EPOR) signaling was impaired in SS erythroid cells. Furthermore, SS mice exhibited reduced responses to EPO. Injection of mice with red cell lysates or hemin, mimicking hemolysis in SCD, led to suppression of erythropoiesis and reduced EPO/EPOR signaling, indicating hemolysis, a hallmark of SCD, and could contribute to the impaired erythropoiesis in SCD. In vitro hemin treatment did not affect Stat5 phosphorylation, suggesting that hemin-induced erythropoiesis suppression in vivo is via an indirect mechanism. Treatment with interferon α (IFNα), which is upregulated by hemolysis and elevated in SCD, led to suppression of mouse BM erythropoiesis in vivo and human erythropoiesis in vitro, along with inhibition of Stat5 phosphorylation. Notably, in sickle erythroid cells, IFN-1 signaling was activated and the expression of cytokine inducible SH2-containing protein (CISH), a negative regulator of EPO/EPOR signaling, was increased. CISH deletion in human erythroblasts partially rescued IFNα-mediated impairment of cell growth and EPOR signaling. Knocking out Ifnar1 in SS mice rescued the defective BM erythropoiesis and improved EPO/EPOR signaling. Our findings identify an unexpected role of hemolysis on the impaired erythropoiesis in SCD through inhibition of EPO/EPOR signaling via a heme-IFNα-CISH axis.


Asunto(s)
Anemia de Células Falciformes , Eritropoyesis , Ratones , Animales , Humanos , Eritropoyesis/fisiología , Factor de Transcripción STAT5/metabolismo , Hemólisis , Hemina/metabolismo , Receptores de Eritropoyetina/genética , Receptores de Eritropoyetina/metabolismo , Anemia de Células Falciformes/complicaciones
3.
Plant Cell ; 35(8): 3053-3072, 2023 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-37100425

RESUMEN

The ketocarotenoid fucoxanthin and its derivatives can absorb blue-green light enriched in marine environments. Fucoxanthin is widely adopted by phytoplankton species as a main light-harvesting pigment, in contrast to land plants that primarily employ chlorophylls. Despite its supreme abundance in the oceans, the last steps of fucoxanthin biosynthesis have remained elusive. Here, we identified the carotenoid isomerase-like protein CRTISO5 as the diatom fucoxanthin synthase that is related to the carotenoid cis-trans isomerase CRTISO from land plants but harbors unexpected enzymatic activity. A crtiso5 knockout mutant in the model diatom Phaeodactylum tricornutum completely lacked fucoxanthin and accumulated the acetylenic carotenoid phaneroxanthin. Recombinant CRTISO5 converted phaneroxanthin into fucoxanthin in vitro by hydrating its carbon-carbon triple bond, instead of functioning as an isomerase. Molecular docking and mutational analyses revealed residues essential for this activity. Furthermore, a photophysiological characterization of the crtiso5 mutant revealed a major structural and functional role of fucoxanthin in photosynthetic pigment-protein complexes of diatoms. As CRTISO5 hydrates an internal alkyne physiologically, the enzyme has unique potential for biocatalytic applications. The discovery of CRTISO5 illustrates how neofunctionalization leads to major diversification events in evolution of photosynthetic mechanisms and the prominent brown coloration of most marine photosynthetic eukaryotes.


Asunto(s)
Diatomeas , Xantófilas , Simulación del Acoplamiento Molecular , Xantófilas/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Diatomeas/genética , Diatomeas/metabolismo
4.
Plant J ; 118(6): 1991-2002, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38549549

RESUMEN

As a major worldwide root crop, the mechanism underlying storage root yield formation has always been a hot topic in sweet potato [Ipomoea batatas (L.) Lam.]. Previously, we conducted the transcriptome database of differentially expressed genes between the cultivated sweet potato cultivar "Xushu18," its diploid wild relative Ipomoea triloba without storage root, and their interspecific somatic hybrid XT1 with medium-sized storage root. We selected one of these candidate genes, IbNF-YA1, for subsequent analysis. IbNF-YA1 encodes a nuclear transcription factor Y subunit alpha (NF-YA) gene, which is significantly induced by the natural auxin indole-3-acetic acid (IAA). The storage root yield of the IbNF-YA1 overexpression (OE) plant decreased by 29.15-40.22% compared with the wild type, while that of the RNAi plant increased by 10.16-21.58%. Additionally, IAA content increased significantly in OE plants. Conversely, the content of IAA decreased significantly in RNAi plants. Furthermore, real-time quantitative reverse transcription-PCR (qRT-PCR) analysis demonstrated that the expressions of the key genes IbYUCCA2, IbYUCCA4, and IbYUCCA8 in the IAA biosynthetic pathway were significantly changed in transgenic plants. The results indicated that IbNF-YA1 could directly target IbYUCCA4 and activate IbYUCCA4 transcription. The IAA content of IbYUCCA4 OE plants increased by 71.77-98.31%. Correspondingly, the storage root yield of the IbYUCCA4 OE plant decreased by 77.91-80.52%. These findings indicate that downregulating the IbNF-YA1 gene could improve the storage root yield in sweet potato.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Ipomoea batatas , Proteínas de Plantas , Raíces de Plantas , Factor de Unión a CCAAT/genética , Factor de Unión a CCAAT/metabolismo , Ácidos Indolacéticos/metabolismo , Ipomoea batatas/genética , Ipomoea batatas/crecimiento & desarrollo , Ipomoea batatas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente
5.
Am J Hum Genet ; 109(1): 157-171, 2022 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-34932939

RESUMEN

Asthenoteratozoospermia, defined as reduced sperm motility and abnormal sperm morphology, is a disorder with considerable genetic heterogeneity. Although previous studies have identified several asthenoteratozoospermia-associated genes, the etiology remains unknown for the majority of affected men. Here, we performed whole-exome sequencing on 497 unrelated men with asthenoteratozoospermia and identified DNHD1 bi-allelic variants from eight families (1.6%). All detected variants were predicted to be deleterious via multiple bioinformatics tools. Hematoxylin and eosin (H&E) staining revealed that individuals with bi-allelic DNHD1 variants presented striking abnormalities of the flagella; transmission electron microscopy (TEM) further showed flagellar axoneme defects, including central pair microtubule (CP) deficiency and mitochondrial sheath (MS) malformations. In sperm from fertile men, DNHD1 was localized to the entire flagella of the normal sperm; however, it was nearly absent in the flagella of men with bi-allelic DNHD1 variants. Moreover, abundance of the CP markers SPAG6 and SPEF2 was significantly reduced in spermatozoa from men harboring bi-allelic DNHD1 variants. In addition, Dnhd1 knockout male mice (Dnhd1‒/‒) exhibited asthenoteratozoospermia and infertility, a finding consistent with the sperm phenotypes present in human subjects with DNHD1 variants. The female partners of four out of seven men who underwent intracytoplasmic sperm injection therapy subsequently became pregnant. In conclusion, our study showed that bi-allelic DNHD1 variants cause asthenoteratozoospermia, a finding that provides crucial insights into the biological underpinnings of this disorder and should assist with counseling of affected individuals.


Asunto(s)
Alelos , Astenozoospermia/genética , Axonema/genética , Dineínas/genética , Flagelos/genética , Predisposición Genética a la Enfermedad , Mutación , Animales , Astenozoospermia/diagnóstico , Axonema/patología , Biología Computacional/métodos , Análisis Mutacional de ADN , Modelos Animales de Enfermedad , Flagelos/patología , Frecuencia de los Genes , Estudios de Asociación Genética , Humanos , Infertilidad Masculina/genética , Masculino , Ratones , Ratones Noqueados , Mitocondrias/genética , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Linaje , Fenotipo , Análisis de Semen , Cola del Espermatozoide/patología , Cola del Espermatozoide/ultraestructura , Secuenciación del Exoma
6.
Plant Physiol ; 194(2): 787-804, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-37815230

RESUMEN

Root development influences plant responses to environmental conditions, and well-developed rooting enhances plant survival under abiotic stress. However, the molecular and genetic mechanisms underlying root development and abiotic stress tolerance in plants remain unclear. In this study, we identified the MYB transcription factor-encoding gene IbMYB73 by cDNA-amplified fragment length polymorphism and RNA-seq analyses. IbMYB73 expression was greatly suppressed under abiotic stress in the roots of the salt-tolerant sweet potato (Ipomoea batatas) line ND98, and its promoter activity in roots was significantly reduced by abscisic acid (ABA), NaCl, and mannitol treatments. Overexpression of IbMYB73 significantly inhibited adventitious root growth and abiotic stress tolerance, whereas IbMYB73-RNAi plants displayed the opposite pattern. IbMYB73 influenced the transcription of genes involved in the ABA pathway. Furthermore, IbMYB73 formed homodimers and activated the transcription of ABA-responsive protein IbGER5 by binding to an MYB binding sites I motif in its promoter. IbGER5 overexpression significantly inhibited adventitious root growth and abiotic stress tolerance concomitantly with a reduction in ABA content, while IbGER5-RNAi plants showed the opposite effect. Collectively, our results demonstrated that the IbMYB73-IbGER5 module regulates ABA-dependent adventitious root growth and abiotic stress tolerance in sweet potato, which provides candidate genes for the development of elite crop varieties with well-developed root-mediated abiotic stress tolerance.


Asunto(s)
Ácido Abscísico , Ipomoea batatas , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Estrés Fisiológico/fisiología , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
7.
Plant Cell ; 34(9): 3301-3318, 2022 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-35670739

RESUMEN

Strigolactones (SLs) constitute a class of plant hormones that regulate many aspects of plant development, including repressing tillering in rice (Oryza sativa). However, how SL pathways are regulated is still poorly understood. Here, we describe a rice mutant dwarf and high tillering1 (dht1), which exhibits pleiotropic phenotypes (such as dwarfism and increased tiller numbers) similar to those of mutants defective in SL signaling. We show that DHT1 encodes a monocotyledon-specific hnRNP-like protein that acts as a previously unrecognized intron splicing factor for many precursor mRNAs (pre-mRNAs), including for the SL receptor gene D14. We find that the dht1 (DHT1I232F) mutant protein is impaired in its stability and RNA binding activity, causing defective splicing of D14 pre-mRNA and reduced D14 expression, and consequently leading to the SL signaling-defective phenotypes. Overall, our findings deepen our understanding of the functional diversification of hnRNP-like proteins and establish a connection between posttranscriptional splicing and SL signaling in the regulation of plant development.


Asunto(s)
Oryza , Regulación de la Expresión Génica de las Plantas , Ribonucleoproteínas Nucleares Heterogéneas , Lactonas , Mutación , Proteínas de Plantas , Precursores del ARN
8.
Nat Chem Biol ; 19(4): 468-477, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36635564

RESUMEN

Membrane dynamics are important to the integrity and function of mitochondria. Defective mitochondrial fusion underlies the pathogenesis of multiple diseases. The ability to target fusion highlights the potential to fight life-threatening conditions. Here we report a small molecule agonist, S89, that specifically promotes mitochondrial fusion by targeting endogenous MFN1. S89 interacts directly with a loop region in the helix bundle 2 domain of MFN1 to stimulate GTP hydrolysis and vesicle fusion. GTP loading or competition by S89 dislodges the loop from the GTPase domain and unlocks the molecule. S89 restores mitochondrial and cellular defects caused by mitochondrial DNA mutations, oxidative stress inducer paraquat, ferroptosis inducer RSL3 or CMT2A-causing mutations by boosting endogenous MFN1. Strikingly, S89 effectively eliminates ischemia/reperfusion (I/R)-induced mitochondrial damage and protects mouse heart from I/R injury. These results reveal the priming mechanism for MFNs and provide a therapeutic strategy for mitochondrial diseases when additional mitochondrial fusion is beneficial.


Asunto(s)
Dinámicas Mitocondriales , Proteínas de Transporte de Membrana Mitocondrial , Ratones , Animales , Proteínas de Transporte de Membrana Mitocondrial/análisis , Proteínas de Transporte de Membrana Mitocondrial/química , Proteínas de Transporte de Membrana Mitocondrial/genética , Mitocondrias , Hidrólisis , Guanosina Trifosfato/análisis , Guanosina Trifosfato/farmacología , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/análisis , Proteínas Mitocondriales/farmacología
9.
EMBO Rep ; 24(2): e55778, 2023 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-36440627

RESUMEN

Following meiotic recombination, each pair of homologous chromosomes acquires at least one crossover, which ensures accurate chromosome segregation and allows reciprocal exchange of genetic information. Recombination failure often leads to meiotic arrest, impairing fertility, but the molecular basis of recombination remains elusive. Here, we report a homozygous M1AP splicing mutation (c.1074 + 2T > C) in patients with severe oligozoospermia owing to meiotic metaphase I arrest. The mutation abolishes M1AP foci on the chromosome axes, resulting in decreased recombination intermediates and crossovers in male mouse models. M1AP interacts with the mammalian ZZS (an acronym for yeast proteins Zip2-Zip4-Spo16) complex components, SHOC1, TEX11, and SPO16. M1AP localizes to chromosomal axes in a SPO16-dependent manner and colocalizes with TEX11. Ablation of M1AP does not alter SHOC1 localization but reduces the recruitment of TEX11 to recombination intermediates. M1AP shows cytoplasmic localization in fetal oocytes and is dispensable for fertility and crossover formation in female mice. Our study provides the first evidence that M1AP acts as a copartner of the ZZS complex to promote crossover formation and meiotic progression in males.


Asunto(s)
Meiosis , Complejos Multiproteicos , Animales , Femenino , Masculino , Ratones , Meiosis/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Ciclo Celular/metabolismo , Complejos Multiproteicos/metabolismo
10.
J Immunol ; 211(3): 462-473, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37326485

RESUMEN

Cell spreading is an initial and critical step in neutrophil adhesion and migration, leading to neutrophil recruitment to inflammatory tissues. Sideroflexin (Sfxn) family proteins are metabolite transporters located in the mitochondrial membrane. Recombinant SFXN5 protein is a citrate transporter in vitro; however, whether Sfxn5 regulates any cellular behavior or function remains unknown. In this study, we found that small interfering RNA transfection or morpholino injection achieving Sfxn5 deficiency in neutrophils significantly decreased neutrophil recruitment in mice and zebrafish, respectively. Sfxn5 deficiency impaired neutrophil spreading and spreading-associated cellular phenotypes, such as cell adhesion, chemotaxis, and ROS production. Actin polymerization is critical for neutrophil spreading, and we found that actin polymerization in spreading neutrophils was partially inhibited by Sfxn5 deficiency. Mechanistically, we observed that the levels of cytosolic citrate and its downstream metabolic products, acetyl-CoA and cholesterol, were decreased in Sfxn5-deficient neutrophils. The levels of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), a mediator for the regulation of actin polymerization by cholesterol, were reduced in the plasma membrane of Sfxn5-deficient neutrophils. Exogenous supplementation with citrate or cholesterol partially reversed the reduction in PI(4,5)P2 levels, defective neutrophil actin polymerization, and cell spreading. Altogether, we demonstrated that Sfxn5 maintains cytosolic citrate levels and ensures the synthesis of sufficient cholesterol to promote actin polymerization in a PI(4,5)P2-dependent manner during neutrophil spreading, which is essential for the eventual inflammatory recruitment of neutrophils. Our study revealed the importance of Sfxn5 in neutrophil spreading and migration, thus identifying, to our knowledge, for the first time, the physiological cellular functions of the Sfxn5 gene.


Asunto(s)
Actinas , Neutrófilos , Animales , Ratones , Actinas/metabolismo , Neutrófilos/metabolismo , Ácido Cítrico/metabolismo , Pez Cebra/metabolismo , Polimerizacion , Colesterol/metabolismo
11.
Cell Mol Life Sci ; 81(1): 402, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39276234

RESUMEN

The excessive inflammation caused by the prolonged activation of Toll-like receptor 4 (TLR4) and its downstream signaling pathways leads to sepsis. CD14-mediated endocytosis of TLR4 is the key step to control the amount of TLR4 on cell membrane and the activity of downstream pathways. The actin cytoskeleton is necessary for receptor-mediated endocytosis, but its role in TLR4 endocytosis remains elusive. Here we show that Tropomodulin 1 (Tmod1), an actin capping protein, inhibited lipopolysaccharide (LPS)-induced TLR4 endocytosis and intracellular trafficking in macrophages. Thus it resulted in increased surface TLR4 and the upregulation of myeloid differentiation factor 88 (MyD88)-dependent pathway and the downregulation of TIR domain-containing adaptor-inducing interferon-ß (TRIF)-dependent pathway, leading to the enhanced secretion of inflammatory cytokines, such as TNF-α and IL-6, and the reduced secretion of cytokines, such as IFN-ß. Macrophages deficient with Tmod1 relieved the inflammatory response in LPS-induced acute lung injury mouse model. Mechanistically, Tmod1 negatively regulated LPS-induced TLR4 endocytosis and inflammatory response through modulating the activity of CD14/Syk/PLCγ2/IP3/Ca2+ signaling pathway, the reorganization of actin cytoskeleton, and the membrane tension. Therefore, Tmod1 is a key regulator of inflammatory response and immune functions in macrophages and may be a potential target for the treatment of excessive inflammation and sepsis.


Asunto(s)
Endocitosis , Inflamación , Lipopolisacáridos , Macrófagos , Ratones Endogámicos C57BL , Transducción de Señal , Receptor Toll-Like 4 , Tropomodulina , Animales , Receptor Toll-Like 4/metabolismo , Lipopolisacáridos/farmacología , Ratones , Macrófagos/metabolismo , Macrófagos/inmunología , Inflamación/metabolismo , Inflamación/patología , Tropomodulina/metabolismo , Tropomodulina/genética , Citocinas/metabolismo , Células RAW 264.7 , Factor 88 de Diferenciación Mieloide/metabolismo , Factor 88 de Diferenciación Mieloide/genética , Receptores de Lipopolisacáridos/metabolismo , Masculino , Ratones Noqueados , Citoesqueleto de Actina/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/genética , Lesión Pulmonar Aguda/metabolismo , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/patología
12.
Drug Resist Updat ; 73: 101057, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38266355

RESUMEN

AIMS: Lung cancer is the leading cause of cancer mortality and lung adenocarcinoma (LUAD) accounts for more than half of all lung cancer cases. Tumor elimination is mostly hindered by drug resistance and the mechanisms remain to be explored in LUAD. METHODS: CRISPR screens in cell and murine models and single-cell RNA sequencing were conducted, which identified MAF bZIP transcription factor F (MAFF) as a critical factor regulating tumor growth and treatment resistance in LUAD. RNA and ChIP sequencing analyses were performed for transcriptional target expression and specific binding sites of MAFF. Functions of MAFF in inhibiting tumor growth and promoting cisplatin or irradiation efficacy were investigated using cellular and xenograft models. RESULTS: Patients with lung adenocarcinoma and reduced MAFF expression had worse clinical outcomes. MAFF inhibited tumor cell proliferation by regulating the expression of SLC7A11, CDK6, and CDKN2C, promoting ferroptosis and preventing cell cycle progression from G1 to S. MAFF also conferred tumor cells vulnerable to cisplatin-based or ionizing radiation treatments. MAFF reduction was a final event in the acquisition of cisplatin resistance of LUAD cells. The intracellular cAMP/PKA/CREB1 pathway upregulated MAFF in response to cisplatin-based or ionizing radiation treatments. CONCLUSIONS: MAFF suppresses tumor growth, and pharmacological agonists targeting MAFF may improve cisplatin or irradiation therapies for lung adenocarcinoma patients.


Asunto(s)
Adenocarcinoma del Pulmón , Ferroptosis , Neoplasias Pulmonares , Humanos , Animales , Ratones , Cisplatino/farmacología , Cisplatino/uso terapéutico , Ferroptosis/genética , Línea Celular Tumoral , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/radioterapia , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/radioterapia , Proliferación Celular , Ciclo Celular , Proteínas Nucleares/metabolismo , Proteínas Nucleares/uso terapéutico , Factor de Transcripción MafF
13.
Proc Natl Acad Sci U S A ; 119(38): e2203708119, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36095219

RESUMEN

Fucoxanthin is a major light-harvesting pigment in ecologically important algae such as diatoms, haptophytes, and brown algae (Phaeophyceae). Therefore, it is a major driver of global primary productivity. Species of these algal groups are brown colored because the high amounts of fucoxanthin bound to the proteins of their photosynthetic machineries enable efficient absorption of green light. While the structure of these fucoxanthin-chlorophyll proteins has recently been resolved, the biosynthetic pathway of fucoxanthin is still unknown. Here, we identified two enzymes central to this pathway by generating corresponding knockout mutants of the diatom Phaeodactylum tricornutum that are green due to the lack of fucoxanthin. Complementation of the mutants with the native genes or orthologs from haptophytes restored fucoxanthin biosynthesis. We propose a complete biosynthetic path to fucoxanthin in diatoms and haptophytes based on the carotenoid intermediates identified in the mutants and in vitro biochemical assays. It is substantially more complex than anticipated and reveals diadinoxanthin metabolism as the central regulatory hub connecting the photoprotective xanthophyll cycle and the formation of fucoxanthin. Moreover, our data show that the pathway evolved by repeated duplication and neofunctionalization of genes for the xanthophyll cycle enzymes violaxanthin de-epoxidase and zeaxanthin epoxidase. Brown algae lack diadinoxanthin and the genes described here and instead use an alternative pathway predicted to involve fewer enzymes. Our work represents a major step forward in elucidating the biosynthesis of fucoxanthin and understanding the evolution, biogenesis, and regulation of the photosynthetic machinery in algae.


Asunto(s)
Diatomeas , Phaeophyceae , Xantófilas , Vías Biosintéticas/genética , Carotenoides/metabolismo , Diatomeas/genética , Diatomeas/metabolismo , Phaeophyceae/metabolismo , Xantófilas/metabolismo
14.
BMC Genomics ; 25(1): 91, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38253995

RESUMEN

BACKGROUND: Spodoptera litura is a harmful pest that feeds on more than 80 species of plants, and can be infected and killed by Spodoptera litura nucleopolyhedrovirus (SpltNPV). SpltNPV-C3 is a type C SpltNPV clone, that was observed and collected in Japan. Compared with type A or type B SpltNPVs, SpltNPV-C3 can cause the rapid mortality of S. litura larvae. METHODS: In this study, occlusion bodies (OBs) and occlusion-derived viruses (ODVs) of SpltNPV-C3 were purified, and OBs were observed by scanning electron microscopy (SEM). ODVs were observed under a transmission electron microscope (TEM). RESULTS: Both OBs and ODVs exhibit morphological characteristics typical of nucleopolyhedroviruses (NPVs).The genome of SpltNPV-C3 was sequenced and analyzed; the total length was 148,634 bp (GenBank accession 780,426,which was submitted as SpltNPV-II), with a G + C content of 45%. A total of 149 predicted ORFs were found. A phylogenetic tree of 90 baculoviruses was constructed based on core baculovirus genes. LC‒MS/MS was used to analyze the proteins of SpltNPV-C3; 34 proteins were found in the purified ODVs, 15 of which were core proteins. The structure of the complexes formed by per os infectivity factors 1, 2, 3 and 4 (PIF-1, PIF-2, PIF-3 and PIF-4) was predicted with the help of the AlphaFold multimer tool and predicted conserved sequences in PIF-3. SpltNPV-C3 is a valuable species because of its virulence, and the analysis of its genome and proteins in this research will be beneficial for pest control efforts.


Asunto(s)
Nucleopoliedrovirus , Proteoma , Animales , Nucleopoliedrovirus/genética , Spodoptera , Cromatografía Liquida , Filogenia , Espectrometría de Masas en Tándem , Baculoviridae
15.
BMC Genomics ; 25(1): 572, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844832

RESUMEN

KNOXs, a type of homeobox genes that encode atypical homeobox proteins, play an essential role in the regulation of growth and development, hormonal response, and abiotic stress in plants. However, the KNOX gene family has not been explored in sweet potato. In this study, through sequence alignment, genomic structure analysis, and phylogenetic characterization, 17, 12 and 11 KNOXs in sweet potato (I. batatas, 2n = 6x = 90) and its two diploid relatives I. trifida (2n = 2x = 30) and I. triloba (2n = 2x = 30) were identified. The protein physicochemical properties, chromosome localization, phylogenetic relationships, gene structure, protein interaction network, cis-elements of promoters, tissue-specific expression and expression patterns under hormone treatment and abiotic stresses of these 40 KNOX genes were systematically studied. IbKNOX4, -5, and - 6 were highly expressed in the leaves of the high-yield varieties Longshu9 and Xushu18. IbKNOX3 and IbKNOX8 in Class I were upregulated in initial storage roots compared to fibrous roots. IbKNOXs in Class M were specifically expressed in the stem tip and hardly expressed in other tissues. Moreover, IbKNOX2 and - 6, and their homologous genes were induced by PEG/mannitol and NaCl treatments. The results showed that KNOXs were involved in regulating growth and development, hormone crosstalk and abiotic stress responses between sweet potato and its two diploid relatives. This study provides a comparison of these KNOX genes in sweet potato and its two diploid relatives and a theoretical basis for functional studies.


Asunto(s)
Diploidia , Regulación de la Expresión Génica de las Plantas , Ipomoea batatas , Familia de Multigenes , Filogenia , Proteínas de Plantas , Estrés Fisiológico , Ipomoea batatas/genética , Ipomoea batatas/crecimiento & desarrollo , Ipomoea batatas/metabolismo , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Genoma de Planta , Perfilación de la Expresión Génica , Regiones Promotoras Genéticas
16.
J Am Chem Soc ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38848464

RESUMEN

Histone monoaminylation (i.e., serotonylation and dopaminylation) is an emerging category of epigenetic mark occurring on the fifth glutamine (Q5) residue of H3 N-terminal tail, which plays significant roles in gene transcription. Current analysis of histone monoaminylation is mainly based on site-specific antibodies and mass spectrometry, which either lacks high resolution or is time-consuming. In this study, we report the development of chemical probes for bioorthogonal labeling and enrichment of histone serotonylation and dopaminylation. These probes were successfully applied for the monoaminylation analysis of in vitro biochemical assays, cells, and tissue samples. The enrichment of monoaminylated histones by the probes further confirmed the crosstalk between H3Q5 monoaminylation and H3K4 methylation. Finally, combining the ex vivo and in vitro analyses based on the developed probes, we have shown that both histone serotonylation and dopaminylation are highly enriched in tumor tissues that overexpress transglutaminase 2 (TGM2) and regulate the three-dimensional architecture of cellular chromatin.

17.
J Neurochem ; 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39289038

RESUMEN

Glioblastoma (GBM) is one of the most prevalent cancerous brain tumors. Former studies have reported that exosomes derived from M1-polarized macrophages (M1 exosomes) inhibit tumor occurrence and development through delivery of tumor suppressor genes. Also, microRNA-142-3p (miR-142-3p) has been verified to function as a tumor suppressor. GBM cell proliferation was evaluated by Cell Counting Kit-8 (CCK-8), colony formation assay and 5-ethynyl-2'-deoxyuridine (EdU) assay; cell apoptosis was determined by flow cytometry analysis and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Mechanism investigations were conducted for analyzing the molecular mechanism by which miR-142-3p and M1 exosomes affect GBM progression. Upregulation of miR-142-3p expression was detected in M1-polarized macrophages and M1 exosomes. M1 exosomes inhibit GBM cell proliferation and trigger cell apoptosis. Functionally, miR-142-3p silencing promotes the proliferation and inhibits the apoptosis of GBM cells treated with M1 exosomes. As for molecular mechanism, miR-142-3p inhibits GBM cell growth via targeting high-mobility group box 1 (HMGB1). In addition, miR-142-3p/HMGB1 axis affects GBM cell immune escape through modulation of programmed death-1/programmed death ligand-1 (PD-1/PD-L1) checkpoint. Our study demonstrated that exosomal miR-142-3p from M1-polarized macrophages suppresses cell growth and immune escape in GBM through regulating HMGB1-mediated PD-1/PD-L1 checkpoint.

18.
Apoptosis ; 29(5-6): 570-585, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38127283

RESUMEN

Integrin ß6 (ITGB6), a member of the integrin family of proteins, is only present in epithelial tissues and frequently associates with integrin subunit αv to form transmembrane heterodimers named integrin αvß6. Importantly, ITGB6 determines αvß6 expression and availability. In addition to being engaged in organ fibrosis, ITGB6 is also directly linked to the emergence of cancer, periodontitis, and several potential genetic diseases. Therefore, it is of great significance to study the molecular-biological mechanism of ITGB6, which could provide novel insights for future clinical diagnosis and therapy. This review introduces the structure, distribution, and biological function of ITGB6. This review also expounds on ITGB6-related diseases, detailing the known biological effects of ITGB6.


Asunto(s)
Antígenos de Neoplasias , Fibrosis , Neoplasias , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Fibrosis/genética , Fibrosis/metabolismo , Animales , Cadenas beta de Integrinas/metabolismo , Cadenas beta de Integrinas/genética , Integrinas/metabolismo , Integrinas/genética , Periodontitis/genética , Periodontitis/metabolismo , Periodontitis/patología
19.
Am J Hum Genet ; 108(8): 1466-1477, 2021 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-34237282

RESUMEN

Multiple morphological abnormalities of the sperm flagella (MMAF)-induced asthenoteratozoospermia is a common cause of male infertility. Previous studies have identified several MMAF-associated genes, highlighting the condition's genetic heterogeneity. To further define the genetic causes underlying MMAF, we performed whole-exome sequencing in a cohort of 643 Chinese MMAF-affected men. Bi-allelic DNAH10 variants were identified in five individuals with MMAF from four unrelated families. These variants were either rare or absent in public population genome databases and were predicted to be deleterious by multiple bioinformatics tools. Morphological and ultrastructural analyses of the spermatozoa obtained from men harboring bi-allelic DNAH10 variants revealed striking flagellar defects with the absence of inner dynein arms (IDAs). DNAH10 encodes an axonemal IDA heavy chain component that is predominantly expressed in the testes. Immunostaining analysis indicated that DNAH10 localized to the entire sperm flagellum of control spermatozoa. In contrast, spermatozoa from the men harboring bi-allelic DNAH10 variants exhibited an absence or markedly reduced staining intensity of DNAH10 and other IDA components, including DNAH2 and DNAH6. Furthermore, the phenotypes were recapitulated in mouse models lacking Dnah10 or expressing a disease-associated variant, confirming the involvement of DNAH10 in human MMAF. Altogether, our findings in humans and mice demonstrate that DNAH10 is essential for sperm flagellar assembly and that deleterious bi-allelic DNAH10 variants can cause male infertility with MMAF. These findings will provide guidance for genetic counseling and insights into the diagnosis of MMAF-associated asthenoteratozoospermia.


Asunto(s)
Astenozoospermia/complicaciones , Modelos Animales de Enfermedad , Dineínas/genética , Infertilidad Masculina/patología , Mutación , Fenotipo , Espermatozoides/patología , Alelos , Animales , Homocigoto , Humanos , Infertilidad Masculina/etiología , Infertilidad Masculina/metabolismo , Masculino , Ratones , Ratones Noqueados , Espermatozoides/metabolismo , Secuenciación del Exoma
20.
Am J Hum Genet ; 108(2): 324-336, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33508233

RESUMEN

Human infertility is a multifactorial disease that affects 8%-12% of reproductive-aged couples worldwide. However, the genetic causes of human infertility are still poorly understood. Synaptonemal complex (SC) is a conserved tripartite structure that holds homologous chromosomes together and plays an indispensable role in the meiotic progression. Here, we identified three homozygous mutations in the SC coding gene C14orf39/SIX6OS1 in infertile individuals from different ethnic populations by whole-exome sequencing (WES). These mutations include a frameshift mutation (c.204_205del [p.His68Glnfs∗2]) from a consanguineous Pakistani family with two males suffering from non-obstructive azoospermia (NOA) and one female diagnosed with premature ovarian insufficiency (POI) as well as a nonsense mutation (c.958G>T [p.Glu320∗]) and a splicing mutation (c.1180-3C>G) in two unrelated Chinese men (individual P3907 and individual P6032, respectively) with meiotic arrest. Mutations in C14orf39 resulted in truncated proteins that retained SYCE1 binding but exhibited impaired polycomplex formation between C14ORF39 and SYCE1. Further cytological analyses of meiosis in germ cells revealed that the affected familial males with the C14orf39 frameshift mutation displayed complete asynapsis between homologous chromosomes, while the affected Chinese men carrying the nonsense or splicing mutation showed incomplete synapsis. The phenotypes of NOA and POI in affected individuals were well recapitulated by Six6os1 mutant mice carrying an analogous mutation. Collectively, our findings in humans and mice highlight the conserved role of C14ORF39/SIX6OS1 in SC assembly and indicate that the homozygous mutations in C14orf39/SIX6OS1 described here are responsible for infertility of these affected individuals, thus expanding our understanding of the genetic basis of human infertility.


Asunto(s)
Azoospermia/genética , Mutación , Insuficiencia Ovárica Primaria/genética , Adulto , Azoospermia/fisiopatología , Emparejamiento Cromosómico , Codón sin Sentido , Proteínas de Unión al ADN/metabolismo , Femenino , Homocigoto , Humanos , Masculino , Meiosis , Persona de Mediana Edad , Proteínas Nucleares/metabolismo , Linaje , Insuficiencia Ovárica Primaria/fisiopatología , Espermatocitos/metabolismo , Espermatocitos/fisiología , Complejo Sinaptonémico/genética , Complejo Sinaptonémico/metabolismo , Secuenciación Completa del Genoma
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