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Limited exploration in fungal mitochondrial genetics has uncovered diverse inheritance modes. The mitochondrial genomes are inherited uniparentally in the majority of sexual eukaryotes, our discovery of persistent mitochondrial heterogeneity within the natural population of the basidiomycete fungus Thelephora ganbajun represents a significant advance in understanding mitochondrial inheritance and evolution in eukaryotes. Here, we present a comprehensive analysis by sequencing and assembling the complete mitogenomes of 40 samples exhibiting diverse cox1 heterogeneity patterns from various geographical origins. Additionally, we identified heterogeneous variants in the nad5 gene, which, similar to cox1, displayed variability across multiple copies. Notably, our study reveals a distinct prevalence of introns and homing endonucleases in these heterogeneous genes. Furthermore, we detected potential instances of horizontal gene transfer involving homing endonucleases. Population genomic analyses underscore regional variations in mitochondrial genome composition among natural samples exhibiting heterogeneity. Thus, polymorphisms in heterogeneous genes, introns, and homing endonucleases significantly influence mitochondrial structure, structural variation, and evolutionary dynamics in this species. This study contributes valuable insights into mitochondrial genome architecture, population dynamics, and the evolutionary implications of mitochondrial heterogeneity in sexual eukaryotes.
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Evolución Molecular , Genoma Mitocondrial , Filogenia , Intrones/genética , Mitocondrias/genética , Basidiomycota/genética , ADN Mitocondrial/genética , Genómica/métodos , Transferencia de Gen HorizontalRESUMEN
This study explores the impact of RNAi in terms of selectively inhibiting the expression of the OsBBTI5 gene, with the primary objective of uncovering its involvement in the molecular mechanisms associated with salt tolerance in rice. OsBBTI5, belonging to the Bowman-Birk inhibitor (BBI) family gene, is known for its involvement in plant stress responses. The gene was successfully cloned from rice, exhibiting transcriptional self-activation in yeast. A yeast two-hybrid assay confirmed its specific binding to OsAPX2 (an ascorbate peroxidase gene). Transgenic OsBBTI5-RNAi plants displayed insensitivity to varying concentrations of 24-epibrassinolide in the brassinosteroid sensitivity assay. However, they showed reduced root and plant height at high concentrations (10 and 100 µM) of GA3 immersion. Enzyme activity assays revealed increased peroxidase (POD) and superoxide dismutase (SOD) activities and decreased malondialdehyde (MDA) content under 40-60 mM NaCl. Transcriptomic analysis indicated a significant upregulation of photosynthesis-related genes in transgenic plants under salt stress compared to the wild type. Notably, this study provides novel insights, suggesting that the BBI gene is part of the BR signaling pathway, and that OsBBTI5 potentially enhances stress tolerance in transgenic plants through interaction with the salt stress-related gene OsAPX2.
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Oryza , Tolerancia a la Sal , Tolerancia a la Sal/genética , Oryza/metabolismo , Interferencia de ARN , Estrés Salino/genética , Peroxidasas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Regulación de la Expresión Génica de las Plantas , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
Natural rubber (NR) composites containing bio-based chitin nanofibers (ChNFs) exhibit a wide range of mechanical properties - from rubber to plastic behavior - with increasing chitin contents. A constrained 3-dimensional network can be formed by mixing natural rubber latex and a modified zwitterionic rigid chitin counterpart. By inclusion of highly anisotropic chitin nanofibers (30 wt%), strain-induced NR crystallization occurs at a much lower strain of 50%. More intriguingly, 2D-WAXD results reveal that the strain-induced crystallization of NR/ChNFs composites show 3-dimensionally oriented crystallite formation behaving similar to "3D-single crystals orientation" when the content of ChNFs is over 5 wt%. It is suggested that not only c-axis (NR chains) orients along the stretching direction, but also the a- and b-axes deliberately arrange along the normal direction and transverse direction, respectively. Structure and morphology in 3-dimensional spaces after strain-induced crystallization of the NR/ChNFs30 composite are investigated in detail. Therefore, this study might pave a new way to enhance mechanical properties by incorporation of ChNFs, obtaining 3-dimensionally oriented crystallites of novel multifunctional NR/ChNFs composite with shape memory ability.
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BACKGROUND: Magnetic resonance imaging (MRI) is a useful non-invasive modality for observation of ovarian morphologic characteristics. Few studies have focused on the value of MRI-derived indexes in reproductive-aged women with polycystic ovary syndrome (PCOS). PURPOSE: To assess the diagnostic value of MRI in women with PCOS. MATERIAL AND METHODS: This prospective case-control study included 85 women with PCOS and 50 controls who underwent pelvic MRI during 2017-2019. Ovarian volume (OV), follicle count (FC; counts of follicles sizing 2-3, 4-6, 7-9, 2-9â mm, respectively), follicular peripheral distribution, absence of a dominant follicle and stromal to total area ratio (S:A) were determined with MRI. The diagnostic value (sensitivity, specificity, area under the receiver operating characteristic curve [AUC]) of OV, FC2-9, and follicular peripheral distribution for PCOS were assessed. RESULTS: The AUCs were 0.94 for OV, 0.96 for FC2-9, and 0.78 for follicular peripheral distribution. The optimal threshold to detect PCOS was 8.5â mL for OV (sensitivity 78%; specificity 96%) and 26 for FC2-9 (sensitivity 85%; specificity 98%). Sensitivity and specificity were 73% and 82% for follicular peripheral distribution, respectively. Reproducibility was perfect for OV (ICC = 0.96) and absence of a dominant follicle (k = 0.85), substantial for FC2-9 (ICC = 0.79) and S:A (ICC = 0.69), and moderate for follicular peripheral distribution (k = 0.56). CONCLUSION: Detected by MRI, OV >8.5â mL or FC2-9 >26 are accurate for diagnosing PCOS.
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Síndrome del Ovario Poliquístico , Femenino , Humanos , Adulto , Síndrome del Ovario Poliquístico/diagnóstico por imagen , Estudios de Casos y Controles , Reproducibilidad de los Resultados , Imagen por Resonancia MagnéticaRESUMEN
The color of the chili fruit is an important factor that determines the quality of the chili, as red chilies are more popular among consumers. The accumulation of capsanthin is the main cause of reddening of the chili fruit. Capsanthin is an important metabolite in carotenoid metabolism, and its production level is closely linked to the expression of the genes for capsanthin/capsorubin synthase (CCS) and carotenoid hydroxylase (CrtZ). We reported for the first time that the synthesis of capsanthin in chili was enhanced by using a geminivirus (Bean Yellow Dwarf Virus). By expressing heterologous ß-carotenoid hydroxylase (CrtZ) and ß-carotenoid ketolase (CrtW) using codon optimization, the transcription level of the CCS gene and endogenous CrtZ was directly increased. This leads to the accumulation of a huge amount of capsanthin in a very short period of time. Our results provide a platform for the rapid enhancement of endogenous CCS activity and capsanthin production using geminivirus in plants.
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Capsicum , Geminiviridae , Proteínas de Plantas/genética , Capsicum/genética , Capsicum/metabolismo , Carotenoides/metabolismo , Oxigenasas de Función Mixta/metabolismo , Geminiviridae/genética , Geminiviridae/metabolismoRESUMEN
Utilizing carbon quantum dots (CQDs) as biomaterials for delivering small substances has gained significant attention in recent research. However, the interactions and mechanisms of action of CQDs on plants have received relatively little focus. Herein, we investigated the transportation of CQDs into various organs of Arabidopsis thaliana (L.) Heynh. via the vessel system, leading to the epigenetic inheritance of Argonaute family genes. Our findings reveal that CQDs may interact with microRNAs (miRNAs), leading to the repression of post-transcriptional regulation of target genes in the cytoplasm. Transcriptome and quantitative PCR analyses demonstrated consistent gene expression levels in offspring. Moreover, microscopic observations illustrated rapid CQD localization on cell membranes and nuclei, with increased nuclear entry at higher concentrations. Notably, our study identified an alternative regulatory microRNA, microRNA172D, for the Argonaute family genes through methylation analysis, shedding light on the connection between CQDs and microRNAs.
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Arabidopsis , MicroARNs , Puntos Cuánticos , Carbono , Arabidopsis/genética , MicroARNs/genética , Expresión GénicaRESUMEN
OBJECTIVE: This study aimed to develop a novel therapeutic vaccine based on a unique B cell epitope and investigate its therapeutic potential against chronic hepatitis B (CHB) in animal models. METHODS: A series of peptides and carrier proteins were evaluated in HBV-tolerant mice to obtain an optimised therapeutic molecule. The immunogenicity, therapeutic efficacy and mechanism of the candidate were investigated systematically. RESULTS: Among the HBsAg-aa119-125-containing peptides evaluated in this study, HBsAg-aa113-135 (SEQ13) exhibited the most striking therapeutic effects. A novel immunoenhanced virus-like particle carrier (CR-T3) derived from the roundleaf bat HBV core antigen (RBHBcAg) was created and used to display SEQ13, forming candidate molecule CR-T3-SEQ13. Multiple copies of SEQ13 displayed on the surface of this particulate antigen promote the induction of a potent anti-HBs antibody response in mice, rabbits and cynomolgus monkeys. Sera and purified polyclonal IgG from the immunised animals neutralised HBV infection in vitro and mediated efficient HBV/hepatitis B virus surface antigen (HBsAg) clearance in the mice. CR-T3-SEQ13-based vaccination induced long-term suppression of HBsAg and HBV DNA in HBV transgenic mice and eradicated the virus completely in hydrodynamic-based HBV carrier mice. The suppressive effects on HBsAg were strongly correlated with the anti-HBs level after vaccination, suggesting that the main mechanism of CR-T3-SEQ13 vaccination therapy was the induction of a SEQ13-specific antibody response that mediated HBV/HBsAg clearance. CONCLUSIONS: The novel particulate protein CR-T3-SEQ13 suppressed HBsAg effectively through induction of a humoural immune response in HBV-tolerant mice. This B cell epitope-based therapeutic vaccine may provide a novel immunotherapeutic agent against chronic HBV infection in humans.
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Epítopos de Linfocito B/inmunología , Antígenos de Superficie de la Hepatitis B/sangre , Vacunas contra Hepatitis B/inmunología , Hepatitis B Crónica/inmunología , Adyuvantes Inmunológicos , Animales , Antivirales/uso terapéutico , Terapia Combinada , ADN Viral/sangre , Relación Dosis-Respuesta Inmunológica , Femenino , Anticuerpos contra la Hepatitis B/biosíntesis , Vacunas contra Hepatitis B/uso terapéutico , Virus de la Hepatitis B/genética , Hepatitis B Crónica/terapia , Hepatitis B Crónica/virología , Inmunidad Humoral/inmunología , Inmunoterapia/métodos , Macaca fascicularis , Masculino , Ratones Endogámicos BALB C , Ratones Transgénicos , ConejosRESUMEN
Ubiquitin-specific protease 18 (USP18) is an important inhibitor of interferon (IFN) antiviral activity, and the aim of this study was to investigate the association between the USP18 mRNA level change in peripheral blood mononuclear cells (PBMCs) when stimulated with IFN in vitro before initiating treatment and the treatment outcomes in HBeAg-positive chronic hepatitis B (CHB) patients treated with IFN. A total of 44 patients who received standard IFN-based anti-HBV therapy and follow-up were enrolled in the study. The in vitro IFN-induced USP18 mRNA change (USP18IFN-N ) was measured via comparison of quantitative PCR-determined USP18 transcription levels of BPMCs cultured with and without IFN stimulation. Either for virological (VR) or serological response (SR), the baseline USP18IFN-N was significantly higher (P = 0.018 for VR, P = 0.008 for SR) among nonresponders (n = 23 for VR, n = 33 for SR) than that of responders (n = 21 for VR, n = 11 for SR). Multivariate analyses revealed baseline USP18IFN-N was a novel independent predictor for either VR (OR = 0.292, 95% CI = 0.102-0.835, P = 0.022) or SR (OR = 0.173, 95% CI = 0.035-0.849, P = 0.031) in our cohort. In addition, baseline USP18IFN-N in combination with HBV DNA loads or HBeAg levels showed improved accuracy of pretreatment prediction for VR or SR responders, respectively. Baseline USP18IFN-N levels are associated with both virological and serological response, and have the potential to become a clinical predictor for treatment outcomes in HBeAg-positive CHB patients before initiating IFN-α therapy.
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Antivirales/farmacología , Antígenos e de la Hepatitis B/sangre , Hepatitis B Crónica/tratamiento farmacológico , Interferón-alfa/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Activación Transcripcional , Ubiquitina Tiolesterasa/genética , Adulto , Antivirales/uso terapéutico , Femenino , Virus de la Hepatitis B/efectos de los fármacos , Humanos , Técnicas In Vitro , Interferón-alfa/uso terapéutico , Masculino , Resultado del TratamientoRESUMEN
OBJECTIVE: To explore the value of magnetic resonance diffusion-weighted imaging (MR-DWI) for evaluating inflammatory activity of perianal Crohn's fistula.â© Methods: A total of 55 patients, who were diagnosed as perianal Crohn's fistula by surgery and/or endoscopy, were assessed retrospectively. All patients, underwent pelvic magnetic resonance imaging (MRI) before and 32 weeks after the treatment, were divided into 2 groups according to their response to treatment: an effective group (34 cases) and an ineffective group (21 cases). The MRI images of patients in the 2 groups were analyzed. The changes of apparent diffusion coefficient (ADC) values before and after treatment in the 2 groups were measured and compared by a paired t-test. An MRI-based score of perianal Crohn's disease severity was calculated as a reference standard, and the correlation between the ADC value and the MRI-based score was analyzed by using a Pearson correlation coefficient method.â© Results: In the effective group, the ADC values after therapy were significantly greater than those before therapy (P<0.05), but in the ineffective group, there was no significant difference in the ADC value between after and before therapy (P>0.05). There was a strong negative correlation between the ADC values (after and before therapy) and the MRI-based scores in all the patients [in the effective group alone (r=-0.672, P<0.01) or in the effective group + the ineffective group (r=-0.638, P<0.01)].â© Conclusion: Changes in the ADC values of perianal fistula are related to the fistula activity. MR-DWI and ADC value can accurately evaluate the inflammatory activity of perianal Crohn's fistula.
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Enfermedad de Crohn , Imagen de Difusión por Resonancia Magnética , Fístula , Humanos , Estudios RetrospectivosRESUMEN
Non-homologous end joining (NHEJ) is one of the major pathways that repairs double-stranded DNA breaks (DSBs). Activation of DNA-PK is required for NHEJ. However, the mechanism leading to DNA-PKcs activation remains incompletely understood. We provide evidence here that the MEK-ERK pathway plays a role in DNA-PKcs-mediated NHEJ. In comparison to the vehicle control (DMSO), etoposide (ETOP)-induced DSBs in MCF7 cells were more rapidly repaired in the presence of U0126, a specific MEK inhibitor, based on the reduction of γH2AX and tail moments. Additionally, U0126 increased reactivation of luciferase activity, which resulted from the repair of restriction enzyme-cleaved DSBs. Furthermore, while inhibition of ERK activation using the dominant-negative MEK1K97M accelerated the repair of DSBs, enforcing ERK activation with the constitutively active MEK1Q56P reduced DSB repair. In line with MEK activating ERK1 and ERK2 kinases, knockdown of either ERK1 or ERK2 increased DSB repair. Consistent with the activation of DNA-PKcs being required for NHEJ, we demonstrated that inhibition of ERK activation using U0126, MEK1K97M, and knockdown of ERK1 or ERK2 enhanced ETOP-induced activation of DNA-PKcs. Conversely, enforcing ERK activation by MEK1Q56P reduced ETOP-initiated DNA-PKcs activation. Taken together, we demonstrate that ERK reduces NHEJ-mediated repair of DSBs via attenuation of DNA-PKcs activation.
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Roturas del ADN de Doble Cadena/efectos de los fármacos , Reparación del ADN por Unión de Extremidades/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Proteínas Nucleares/agonistas , ARN Interferente Pequeño/farmacología , Antineoplásicos Fitogénicos/farmacología , Proteína Quinasa Activada por ADN/metabolismo , Evaluación Preclínica de Medicamentos , Activación Enzimática/efectos de los fármacos , Etopósido/farmacología , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Proteínas Nucleares/metabolismo , Células Tumorales Cultivadas , Regulación hacia Arriba/efectos de los fármacosRESUMEN
Directed self-assembly of materials into patterned structures is of great importance since the performance of them depends remarkably on their multiscale hierarchical structures. Therefore, purposeful structural regulation at different length scales through crystallization engineering provides an opportunity to modify the properties of polymeric materials. Here, an epitaxy-directed self-assembly strategy for regulating the pattern structures including phase structure as well as crystal modification and orientation of each component for both copolymers and polymer blends is reported. Owing to the specific crystallography registration between the depositing crystalline polymers and the underlying crystalline substrate, not only order phase structure with controlled size at nanometer scale but also the crystal structure and chain orientation of each component within the separated phases for both copolymers and polymer blend systems can be precisely regulated.
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The Lanzhou lily (Lilium davidii var. unicolor) is a variant of the Sichuan lily of the lily family and is a unique Chinese 'medicinal and food' sweet lily. Somatic cell embryogenesis of Lilium has played an important role in providing technical support for germplasm conservation, bulb propagation and improvement of genetic traits. Somatic embryogenesis receptor-like kinases (SERKs) are widely distributed in plants and have been shown to play multiple roles in plant life, including growth and development, somatic embryogenesis and hormone induction. Integrating the results of KEGG enrichment, GO annotation and gene expression analysis, a lily LdSERK1 gene was cloned. The full-length open reading frame of LdSERK1 was 1875 bp, encoding 624 amino acids. The results of the phylogenetic tree analysis showed that LdSERK1 was highly similar to rice, maize and other plant SERKs. The results of the subcellular localisation in the onion epidermis suggested that the LdSERK1 protein was localised at the cell membrane. Secondly, we established the virus-induced gene-silencing (VIGS) system in lily scales, and the results of LdSERK1 silencing by Tobacco rattle virus (TRV) showed that, with the down-regulation of LdSERK1 expression, the occurrence of somatic embryogenesis and callus tissue induction in scales was significantly reduced. Finally, molecular assays from overexpression of the LdSERK1 gene in Arabidopsis showed that LdSERK1 expression was significantly enhanced in the three transgenic lines compared to the wild type, and that the probability of inducing callus tissue in seed was significantly higher than that of the wild type at a concentration of 2 mg/L 2,4-D, which was manifested by an increase in the granularity of the callus tissue.
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Therapeutics for eradicating hepatitis B virus (HBV) infection are still limited and current nucleos(t)ide analogs (NAs) and interferon are effective in controlling viral replication and improving liver health, but they cannot completely eradicate the hepatitis B virus and only a very small number of patients are cured of it. The TCR-like antibodies recognizing viral peptides presented on human leukocyte antigens (HLA) provide possible tools for targeting and eliminating HBV-infected hepatocytes. Here, we generated three TCR-like antibodies targeting three different HLA-A2.1-presented peptides derived from HBV core and surface proteins. Bispecific antibodies (BsAbs) were developed by fuzing variable fragments of these TCR-like mAbs with an anti-CD3ϵ antibody. Our data demonstrate that the BsAbs could act as T cell engagers, effectively redirecting and activating T cells to target HBV-infected hepatocytes in vitro and in vivo. In HBV-persistent mice expressing human HLA-A2.1, two infusions of BsAbs induced marked and sustained suppression in serum HBsAg levels and also reduced the numbers of HBV-positive hepatocytes. These findings highlighted the therapeutic potential of TCR-like BsAbs as a new strategy to cure hepatitis B.
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Anticuerpos Biespecíficos , Modelos Animales de Enfermedad , Virus de la Hepatitis B , Hepatitis B , Hepatocitos , Animales , Anticuerpos Biespecíficos/inmunología , Anticuerpos Biespecíficos/farmacología , Hepatocitos/virología , Hepatocitos/inmunología , Ratones , Humanos , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/genética , Hepatitis B/inmunología , Hepatitis B/virología , Antígeno HLA-A2/inmunología , Antígenos de Superficie de la Hepatitis B/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T/inmunologíaRESUMEN
Five novel perhydrobenzannulated 5,5-spiroketal sesquiterpenes, namely, pleurospiroketals A-E (1-5), were isolated from the culture of the edible mushroom Pleurotus cornucopiae. Pleurospiroketals D (4) and E (5) were obtained as an isomeric mixture with a ratio of 5:4. Their structures were established by NMR, X-ray single-crystal diffraction, and CD data analysis. Pleurospiroketals A-E (1-5) are sesquiterpenoids with a unique benzannulated 5,5-spiroketal skeleton. Compounds 1-3 showed inhibitory activity against nitric oxide production in lipopolysaccharide-activated macrophages with IC(50) values of 6.8, 12.6, and 20.8 µM, respectively.
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Furanos/aislamiento & purificación , Pleurotus/química , Sesquiterpenos/aislamiento & purificación , Compuestos de Espiro/aislamiento & purificación , Animales , Cristalografía por Rayos X , Furanos/química , Furanos/farmacología , Células HeLa , Humanos , Concentración 50 Inhibidora , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Ratones , Conformación Molecular , Estructura Molecular , Óxido Nítrico/biosíntesis , Resonancia Magnética Nuclear Biomolecular , Sesquiterpenos/química , Sesquiterpenos/farmacología , Compuestos de Espiro/química , Compuestos de Espiro/farmacología , EstereoisomerismoRESUMEN
Antibacterial peptides are endogenous polypeptides produced by multicellular organisms to protect the host against pathogenic microbes, they show broad spectrum antimicrobial activities against various microorganisms and possess low propensity for developing resistance. The purpose of this study is to develop recombinant antibacterial peptide cathelicidin-BF by genetic engineering and protein engineering technology, and study its antibacterial activity in vitro and in vivo, so as to provide reference for the production and application of recombinant antibacterial peptide cathelicidin-BF. In this study, on account of Pichia pastoris eukaryotic expression system, we expressed and prepared antibacterial peptide cathelicidin-BF. Then, the minimum inhibitory concentration of antibacterial peptide cathelicidin-BF and the comparison with the antibacterial activity of antibiotics were determined through the antibacterial experiment in vitro. Chickens as infection model were used to verify the antibacterial peptide activity in vivo. The results show that the bacteriostatic ability of antibacterial peptide cathelicidin-BF is similar to that of antibiotics in certain concentration, and can reach the treatment level of antibiotics. Although the mode of administration of antibacterial peptide is still limited, this study can provide reference for the future research of antibacterial peptide.
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The Chinese plum (Prunus salicina L.) is a fruit tree belonging to the Rosaceae family, native to south-eastern China and widely cultivated throughout the world. Fruit sugar metabolism and color change is an important physiological behavior that directly determines flavor and aroma. Our study analyzed six stages of fruit growth and development using RNA-seq, yielding a total of 14,973 DEGs, and further evaluation of key DEGs revealed a focus on sugar metabolism, flavonoid biosynthesis, carotenoid biosynthesis, and photosynthesis. Using GO and KEGG to enrich differential genes in the pathway, we selected 107 differential genes and obtained 49 significant differential genes related to glucose metabolism. The results of the correlation analyses indicated that two genes of the SWEET family, evm.TU.Chr1.3663 (PsSWEET9) and evm.TU.Chr4.676 (PsSWEET2), could be closely related to the composition of soluble sugars, which was also confirmed in the ethylene treatment experiments. In addition, analysis of the TOP 20 pathways between different growth stages and the green stage, as well as transient overexpression in chili, suggested that capsanthin/capsorubin synthase (PsCCS) of the carotenoid biosynthetic pathway contributed to the color change of plum fruit. These findings provide an insight into the molecular mechanisms involved in the ripening and color change of plum fruit.
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The bulb formation of Lilium is affected by many physiological and biochemical phenomena, including flower bud differentiation, starch and sucrose accumulation, photoperiod, carbon fixation, plant hormone transduction, etc. The transcriptome analysis of flower buds of Lilium hybrid 'Siberia' at different maturity stages showed that floral bud formation is associated with the accumulation of anthocyanins. The results of HPLC-MS showed that cyanidin is the major anthocyanin found in Lilium 'Siberia'. Transcriptome KEGG enrichment analysis and qRT-PCR validation showed that two genes related to flavonoid biosynthesis (LhANS-rr1 and LhDFR) were significantly up-regulated. The functional analysis of differential genes revealed that LhMYB114 was directly related to anthocyanin accumulation among 19 MYB transcription factors. Furthermore, the qRT-PCR results suggested that their expression patterns were very similar at different developmental stages of the lily bulbs. Virus-induced gene silencing (VIGS) revealed that down-regulation of LhANS-rr1, LhDFR, and LhMYB114 could directly lead to a decrease in anthocyanin accumulation, turning the purple phenotype into a white color. Moreover, this is the first report to reveal that LhMYB114 can regulate anthocyanin accumulation at the mature stage of lily bulbs. The accumulation of anthocyanins is an important sign of lily maturity. Therefore, these findings have laid a solid theoretical foundation for further discussion on lily bulb development in the future.
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Flores , Lilium , Flores/genética , Flores/metabolismo , Lilium/genética , Lilium/metabolismo , Antocianinas , Regulación de la Expresión Génica de las Plantas , Perfilación de la Expresión GénicaRESUMEN
To achieve the sustainable development of the rubber industry, the substitute of carbon black, the most widely used but non-renewable filler produced from petroleum, has been considered one of the most effective ways. The naturally occurring illite with higher aspect ratio can be easily obtained in large amounts at lower cost and with lower energy consumption. Therefore, the expansion of its application in advanced materials is of great significance. To explore their potential use as an additive for reinforcing rubber, styrene butadiene rubber (SBR) composites with illites of different size with and without 3-mercaptopropyltriethoxysilane (KH580) modification were studied. It was found that the modification of illite by KH580 increases the K-illite/SBR interaction, and thus improves the dispersion of K-illite in the SBR matrix. The better dispersion of smaller size K-illite with stronger interfacial interaction improves the mechanical properties of SBR remarkably, by an increment of about nine times the tensile strength and more than ten times the modulus. These results demonstrate, except for the evident effect of particle size, the great importance of filler-rubber interaction on the performance of SBR composites. This may be of great significance for the potential wide use of the abundant naturally occurring illite as substitute filler for the rubber industry.
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The mitochondrial genomes are generally considered non-recombining and homoplasmic in nature. However, our previous study provided the first evidence of extensive and stable mitochondrial heteroplasmy in natural populations of the basidiomycete fungus Thelephora ganbajun from Yunnan province, China. The heteroplasmy was characterized by the presence of two types of introns residing at adjacent but different sites in the cytochrome oxidase subunits I (cox1) gene within an individual strain. However, the frequencies of these two introns among isolates from different geographical populations and the implications for the genetic structure in natural populations have not been investigated. In this study, we analyzed DNA sequence variation at the internal transcribed spacer (ITS) regions of the nuclear ribosomal RNA gene cluster among 489 specimens from 30 geographic locations from Yunnan and compared that variation with distribution patterns of the two signature introns in the cox1 gene that are indicative of heteroplasmy in this species. In our samples, evidence for gene flow, abundant genetic diversity, and genotypic uniqueness among geographic samples in Yunnan were revealed by ITS sequence variation. While there was insignificant positive correlation between geographic distance and genetic differentiation among the geographic samples based on ITS sequences, a moderate significant correlation was found between ITS sequence variation, geographical distance of sampling sites, and distribution patterns of the two heteroplasmic introns in the cox1 gene. Interestingly, there was a significantly negative correlation between the copy numbers of the two co-existing introns. We discussed the implications of our results for a better understanding of the spread of stable mitochondrial heteroplasmy, mito-nuclear interactions, and conservation of this important gourmet mushroom.
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Agaricales , Heteroplasmia , Agaricales/genética , Basidiomycota , China , Flujo GenéticoRESUMEN
Plant promoters play a vital role in the initiation and regulation of gene transcription. In this study, a rice protein/gene of unknown expression, named Os8GSX7, was gained from a rice T-DNA capture line. The semi-quantitative RT-PCR analysis showed that the gene was only expressed in root, glume, and flower, but not in stem, leaf, embryo, and endosperm of japonica rice. The GUS activity analysis of the GSX7R promoter showed that it was a reverse green tissue expression promoter, except in endosperm. The forward promoter of GSX7 cannot normally drive the expression of the foreign GUS gene, while the reverse promoter of GSX7 is a green tissue-specific expression promoter, which can drive the expression of the foreign GUS gene. The region from -2097 to -1543 bp was the key region for controlling the green tissue-specific expression. The regulatory sequences with different lengths from the 2097 bp reverse sequence from the upstream region of the Os8GSX7 were fused with the GUS reporter gene and stably expressed in rice. Furthermore, transgenic rice plants carrying Cry1Ab encoding Bacillus thuringiensis endotoxin, regulated by GSX7R, were resistant to yellow stem borer. The analysis suggested that 10 light responsive elements of tissue-specific expression were found, including ACE, Box4, CAT-box, G-Box, G-box, GATA motif, GC motif, I-box, Sp1, and chs-unit1 M1. In addition, the results of 5' and 3' deletions further speculated that ACE and I-box may be the key elements for determining the green tissue-specific expression of GSX7R promoter.