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The effects of short-term mindfulness are associated with the different patterns (autonomic, audio guided, or experienced and certified mindfulness instructor guided mindfulness). However, robust evidence for reported the impacts of different patterns of mindfulness on mental health and EEG biomarkers of undergraduates is currently lacking. Therefore, we aimed to test the hypotheses that mindfulness training for undergraduates would improve mental health, and increase alpha power over frontal region and theta power over midline region at the single electrode level. We also describe the distinction among frequency bands patterns in different sites of frontal and midline regions. 70 participants were enrolled and assigned to either 5-day mindfulness or a waiting list group. Subjective questionnaires measured mental health and other psychological indicators, and brain activity was recorded during various EEG tasks before and after the intervention. The 5-day mindfulness training improved trait mindfulness, especially observing (p = 0.001, d = 0.96) and nonreactivity (p = 0.03, d = 0.56), sleep quality (p = 0.001, d = 0.91), and social support (p = 0.001, d = 0.95) while not in affect. Meanwhile, the expected increase in the alpha power of frontal sites (p < 0.017, d > 0.84) at the single electrode level was confirmed by the current data rather than the theta. Interestingly, the alteration of low-beta power over the single electrode of the midline (p < 0.05, d > 0.71) was difference between groups. Short-term mindfulness improves practitioners' mental health, and the potentially electrophysiological biomarkers of mindfulness on neuron oscillations were alpha activity over frontal sites and low-beta activity over midline sites.
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Electroencefalografía , Atención Plena , Humanos , Salud Mental , Encuestas y Cuestionarios , BiomarcadoresRESUMEN
Regulated cell death (RCD) refers to programmed cell death regulated by various protein molecules, such as apoptosis, autophagy-dependent cell death, and necroptosis. Accumulating evidence has recently revealed that RCD subroutines have several links to many types of human cancer; therefore, targeting RCD with pharmacological small-molecule compounds would be a promising therapeutic strategy. Moreover, plant natural compounds, small-molecule compounds synthesized from plant sources, and their derivatives have been widely reported to regulate different RCD subroutines to improve potential cancer therapy. Thus, in this review, we focus on updating the intricate mechanisms of apoptosis, autophagy-dependent cell death, and necroptosis in cancer. Moreover, we further discuss several representative plant natural compounds and their derivatives that regulate the above-mentioned three subroutines of RCD, and their potential as candidate small-molecule drugs for the future cancer treatment.
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Muerte Celular Autofágica , Neoplasias , Muerte Celular Regulada , Humanos , Necroptosis , Apoptosis , Neoplasias/tratamiento farmacológicoRESUMEN
Almost all selenogenes are expressed in the testis, and those have the highest and constant expressions will be the primary candidates for functional analysis of selenium (Se) in male reproduction. This study aimed to profile the mRNA expressions of the testis-abundant selenogenes of rat models in responses to growth and dietary Se concentrations. Forty-eight weaning SD male rats were fed Se deficient basal diet (BD) for 5 weeks and then randomly grouped (n = 12/group) for being fed BD or BD plus 0.25, 3, or 5 mg Se/kg for 4 more weeks before sacrifice. Abundances of selenogenomic mRNAs in the liver and testis were determined with relative qPCR and those of the testis-abundant selenogenes in 13 kinds of tissues were assayed with a molecular beacon-based qPCR. Spatiotemporal expressions of rat selenogenome were also analyzed with the RNA-Seq transcriptomic data published by NCBI. mRNA abundances of glutathione peroxidase 4 (Gpx4), nuclear Gpx4 (nGpx4), selenoprotein V (Selenov), and thioredoxin reductase 3 (Txnrd3) in the testis were significantly higher than that in any other tissues (P < 0.05). Moreover, testicular mRNA abundances of Gpx4, Selenov, and Txnrd3 were not affected by levels of dietary Se supplementation (P > 0.05), and much higher at 6-21 weeks old than at 2 and 104 weeks old (P < 0.05). The result showed that Gpx4, Selenov, and Txnrd3 were most highly expressed in the testis of rats especially at reproductive ages and resistant to the impact of dietary Se levels, which suggested their specific importance in male reproduction.
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Selenio , Testículo , Animales , Masculino , Ratas , Glutatión Peroxidasa/metabolismo , Hígado/metabolismo , Reproducción , ARN Mensajero/genética , ARN Mensajero/metabolismo , Selenio/metabolismo , Selenoproteínas/genética , Selenoproteínas/metabolismo , Testículo/metabolismoRESUMEN
Olfaction and food intake are interrelated and regulated. In the process of feeding, the metabolic signals in the body and the feeding signals produced by food stimulation are first sensed by the arcuate nucleus of hypothalamus and the nucleus tractus solitarius of brain stem, and then these neurons project to the paraventricular nucleus of hypothalamus. The paraventricular nucleus transmits the signals to other brain regions related to feeding and regulates feeding behavior. In this process, olfactory signals can be transmitted to hypothalamus through olfactory bulb and olfactory cortex to regulate feeding behavior. At the same time, gastrointestinal hormones (ghrelin, insulin, leptin, etc.) and some neurotransmitters (acetylcholine, norepinephrine, serotonin, endocannabinoid, etc.) produced in the process of feeding act on the olfactory system to regulate olfactory function, which in turn affects the feeding itself. This review summaries the research progress of the interaction between olfaction and food intake and its internal mechanism from the aspects of neuronal and hormonal regulation.
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Conducta Alimentaria , Olfato , Núcleo Arqueado del Hipotálamo/metabolismo , Conducta Alimentaria/fisiología , Hipotálamo , Núcleo Hipotalámico ParaventricularRESUMEN
Pancreatic cancer is the fourth leading cause of cancer-related death and urgently needs biomarkers for clinical diagnosis and prognosis. It has been reported that myoferlin (MYOF) is implicated in the regulation of proliferation, invasion, and migration of tumor cells in many cancers including pancreatic cancer. To confirm the prognostic value of MYOF in pancreatic cancer, a comprehensive cancer versus healthy people analysis was conducted using public data. MYOF mRNA expression levels were compared in many kinds of cancers including pancreatic cancer via the Oncomine and Gene Expression Profiling Interactive Analysis (GEPIA) databases. The results have shown that MYOF mRNA expression levels were upregulated in most types of cancers, especially in pancreatic cancer, compared with healthy people's tissues. Data from the Cancer Cell Line Encyclopedia (CCLE) and European Bioinformatics Institute (EMBL-EML) database also revealed that MYOF mRNA is highly expressed in most cancer cells, particularly in pancreatic cancer cell lines. Furthermore, the prognostic value of MYOF was evaluated using GEPIA and Long-term Outcome and Gene Expression Profiling Database of pan-cancers (LOGpc) database. Higher expression of MYOF was associated with poorer overall survival, especially in the lower stage and lower grade. Coexpressed genes, possible regulators, and the correlation between MYOF expressions were analyzed via the GEPIA and LinkedOmics database. Nineteen coexpressed genes were identified, and most of these genes were related to cancer. The Tumor Immune Estimation Resource (TIMER) database was used to analyze the correlation between MYOF and immune response. Notably, we found that MYOF might have a potential novel immune regulatory role in tumor immunity. These results support that MYOF is a candidate prognostic biomarker for pancreatic cancer, which calls for further genomics research of pancreatic cancer and deeply functional studies on MYOF.
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Proteínas de Unión al Calcio/genética , Proteínas de la Membrana/genética , Proteínas Musculares/genética , Neoplasias Pancreáticas/genética , Biomarcadores de Tumor/genética , Biología Computacional , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Pronóstico , ARN Mensajero/genética , Neoplasias PancreáticasRESUMEN
OBJECTIVES: Autophagy, a highly conserved lysosomal degradation process in eukaryotic cells, has been widely reported closely related to the progression of many types of human cancers, including LGG; however, the intricate relationship between autophagy and LGG remains to be clarified. MATERIALS AND METHODS: Multi-omics methods were used to integrate omics data to determine potential autophagy regulators in LGG. The expression of ZFP36L2 and RAB13 in SW1088 cells was experimentally manipulated using cDNAs and small interfering RNAs (siRNA). RT-qPCR detects RNAi gene knockout and cDNA overexpression efficiency. The expression levels of proteins in SW1088 cells were evaluated using Western blot analysis and immunofluorescence analysis. Homology modelling and molecular docking were used to identify compounds from Multi-Traditional Chinese Medicine (TCM) Databases. The apoptosis ratios were determined by flow cytometry analysis of Annexin-V/PI double staining. We detect the number of autophagosomes by GFP-MRFP-LC3 plasmid transfection to verify the process of autophagy flow. RESULTS: We integrated various omics data from LGG, including EXP, MET and CNA data, with the SNF method and the LASSO algorithm, and identified ZFP36L2 and RAB13 as positive regulators of autophagy, which are closely related to the core autophagy regulators. Both transcription level and protein expression level of the four autophagy regulators, including ULK1, FIP200, ATG16L1 and ATG2B, and LC3 puncta were increased by ZFP36L2 and RAB13 overexpression. In addition, RAB13 participates in autophagy through ATG2B, FIP200, ULK1, ATG16L1 and Beclin-1. Finally, we screened multi-TCM databases and identified gallic acid as a novel potential RAB13 inhibitor, which was confirmed to negatively regulate autophagy as well as to induce cell death in SW1088 cells. CONCLUSION: Our study identified the key autophagic regulators ZFP36L2 and Rab13 in LGG progression, and demonstrated that gallic acid is a small molecular inhibitor of RAB13, which negatively regulates autophagy and provides a possible small molecular medicine for the subsequent treatment of LGG.
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Autofagia , Bases de Datos Factuales , Glioma , Medicina Tradicional China , Simulación del Acoplamiento Molecular , Proteínas de Unión al GTP rab , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Glioma/tratamiento farmacológico , Glioma/enzimología , Humanos , Proteínas de Unión al GTP rab/antagonistas & inhibidores , Proteínas de Unión al GTP rab/metabolismoRESUMEN
Myocardial fibrosis is well-known to be the aberrant deposition of extracellular matrix (ECM), which may cause cardiac dysfunction, morbidity, and death. Traditional Chinese medicine formula Si-Miao-Yong-An Decoction (SMYAD), which is used clinically in cardiovascular diseases has been recently reported to able to resist myocardial fibrosis. The anti-fibrosis effects of SMYAD have been evaluated; however, its intricate mechanisms remain to be clarified. Here, we found that SMYAD treatment reduced the fibrosis injury and collagen fiber deposition that could improve cardiac function in isoprenaline (ISO)-induced fibrosis rat models. Combined with our systematic RNA-seq data of SMYAD treatment, we demonstrated that the remarkable up-regulation or down-regulation of several genes were closely related to the functional enrichment of TGF-ß and AMPK pathways that were involved in myocardial fibrosis. Accordingly, we further explored the molecular mechanisms of SMYAD were mainly caused by AMPK activation and thereby suppressing its downstream Akt/mTOR and TGF-ß/SMAD3 pathways. Moreover, we showed that the ECM deposition and secretion process were attenuated, suggesting that the fibrosis pathological features are changed. Interestingly, we found the similar AMPK-driven pathways in NIH-3T3 mouse fibroblasts treated with ISO. Taken together, these results demonstrate that SMYAD may be a new candidate agent by regulating AMPK-driven Akt/mTOR and TGF-ß/SMAD3 pathways for potential therapeutic implications of myocardial fibrosis.
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Agonistas Adrenérgicos beta , Cardiomiopatías/prevención & control , Medicamentos Herbarios Chinos/uso terapéutico , Isoproterenol , Transducción de Señal/efectos de los fármacos , Animales , Cardiomiopatías/inducido químicamente , Cardiomiopatías/diagnóstico por imagen , Colágeno , Medicamentos Herbarios Chinos/farmacología , Ecocardiografía , Matriz Extracelular/efectos de los fármacos , Fibrosis , Expresión Génica/efectos de los fármacos , Masculino , Ratones , Quinasas de Proteína Quinasa Activadas por Mitógenos/efectos de los fármacos , Células 3T3 NIH , Proteína Oncogénica v-akt/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Transducción de Señal/genética , Proteína smad3/efectos de los fármacos , Serina-Treonina Quinasas TOR/efectos de los fármacos , Factor de Crecimiento Transformador beta/efectos de los fármacosRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Si-Miao-Yong-An decoction (SMYAD) is a traditional Chinese herbal formulation. SMYAD first appeared in the Eastern Han Dynasty according to the "Shen Yi Mi Zhuan". Then the formula was recorded in the "Yan Fang Xin Bian" edited by medical scientist Bao Xiangao in the Qing Dynasty. This well-known prescription has been traditionally used for gangrene and vascular vasculitis. It is mainly used for cardiovascular and endocrine diseases in current clinical applications and research. AIM OF STUDY: In this study, the potential mechanisms of SMYAD against cardiac fibrosis and hypertrophy in the ß-adrenoceptor agonist isoprenaline induced heart failure model were investigated. MATERIALS AND METHODS: The heart failure animal model was established via injected isoprenaline in rats. Echocardiography was used to detect the structure and function of the heart. HE staining and Masson's trichrome staining was performed to assess myocardial tissue morphology. The serum biochemical indexes were detected by dedicated biochemical kit. BNP was tested by ELISA kit. The levels of mRNA were detected by RT-qPCR. Cardiomyocyte morphology was assessed by immunofluorescence. Phosphorylated and total p38, Akt were analyzed by Western blot. The production of reactive oxygen species (ROS) was tested by CM-H2DCFDA probe. Formula identification of chemical constituents of SMYAD in plasma was disclosed through ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF-MS). RESULTS: SMYAD was able to improve the heart function in ISO induced heart failure rat model via protecting rat from developing cardiac hypertrophy and fibrosis. SMYAD also decreased plasma expression of these biochemical indexes. It was found that SMYAD could regulate cardiac hypertrophy and fibrosis makers' mRNA levels in vitro and vivo. In addition, SMYAD inhibited the phosphorylation of p38 and Akt, which are key mediators in the pathological process of ISO-induced cardiac hypertrophy and myocardial fibrosis. It also showed that the components of SMYAD in rat plasma exerted myocardial cell protective activity. CONCLUSION: In summary, SMYAD may comprise more than one active ingredient to the pursuit of combination therapies instead of specifically target a single disease-causing molecule. These experimental results suggest that SMYAD may be a potential drug candidate in diseases of cardiac hypertrophy and myocardial fibrosis caused by ß-adrenoceptor abnormalities.
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Cardiomegalia/prevención & control , Medicamentos Herbarios Chinos/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Animales , Cardiomegalia/etiología , Línea Celular , Doxorrubicina , Medicamentos Herbarios Chinos/farmacología , Fibrosis , Insuficiencia Cardíaca/inducido químicamente , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/metabolismo , Isoproterenol , Masculino , Miocardio/citología , Miocardio/metabolismo , Miocardio/patología , Fitoquímicos/análisis , Fitoquímicos/farmacología , Fitoquímicos/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Mindfulness is described as the non-judgmental awareness of experiences in the present moment. The sustained practice of mindfulness may also have beneficial effects on an individual's well-being. For instance, mindfulness meditation is an effective approach for improving emotion regulation. Specifically, the early stage of mindfulness meditation training enhances emotional monitoring systems related to attention regulation and executive function. Reduced activity in the default mode network (DMN) would probably be observed corresponding to the attenuated mind wandering. In the present study, we hypothesized that alterations in functional activity in the frontal-parietal cortex and DMN may be induced by short-term mindfulness meditation. In this study, before and after 8 weeks of weekly Mindfulness-Based Stress Reduction (MBSR) training, healthy participants were evaluated using a mindfulness questionnaire and an affect schedule, as well as via resting-state functional magnetic resonance imaging. Sixteen right-handed non-meditators were enrolled. Another 16 demographically matched healthy adults without any meditation experience were recruited as controls. Pre- and post-MBSR assessments were compared. Increased regional homogeneity in the right superior parietal lobule and left postcentral gyrus (PoCG), as well as altered functional connectivity in PoCG-related networks, were observed post-MBSR. The mindfulness questionnaire scores also improved and negative affect was significantly decreased after MBSR. Together with reduced involvement of the posterior brain, our results suggest a tendency toward stronger involvement of the parietal cortex in mindfulness beginners. This study provides novel evidence regarding the optimization of emotional processing with short-term mindfulness meditation.
RESUMEN
BACKGROUND: Berberine (BBR), a Chinese traditional herbal medicine, has many pharmacologic benefits such as anti-inflammation and anti-oxidation. It is widely used in clinical treatment of cardiovascular diseases such as hypertension. However, the mechanism of how BBR attenuates hypertension through affecting central neural system is not clear. PURPOSE: This study was designed to determine whether chronic infusion of BBR into the hypothalamic paraventricular nucleus (PVN) attenuates hypertension and sympathoexcitation via the ROS/Erk1/2/iNOS pathway. METHODS: Two-kidney, one-clip (2K1C) renovascular hypertensive rats were randomly assigned and treated with bilateral PVN infusion of BBR (2µg/h) or vehicle (artificial cerebrospinal fluid) via osmotic minipumps for 28 days. RESULTS: 2K1C rats showed higher mean arterial pressure (MAP) and PVN Fra-like activity, plasma levels of norepinephrine (NE), PVN levels of NOX2, NOX4, Erk1/2 and iNOS, and lower PVN levels of copper/zinc superoxide dismutase (Cu/Zn-SOD). Chronic infusion of BBR reduced MAP, PVN Fra-like activity and plasma levels of NE, reduced NOX2, NOX4, Erk1/2, iNOS and induced Cu/Zn-SOD in the PVN. CONCLUSIONS: These results suggest that BBR attenuates hypertension and sympathoexcitation via the ROS/Erk1/2/iNOS pathway in 2K1C renovascular hypertensive rats.
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Berberina/farmacología , Hipertensión/tratamiento farmacológico , Sistema de Señalización de MAP Quinasas , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Animales , Presión Arterial , Masculino , NADPH Oxidasa 2/metabolismo , NADPH Oxidasa 4/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Norepinefrina/sangre , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa-1/metabolismoRESUMEN
Two new tetranorlabdane diterpenoids, named botryosphaerins G (1) and H (2), were isolated from the solid fermentation products of Botryosphaeria sp. P483 along with seven known tetranorlabdane diterpenes (3-9). Their structures were elucidated by extensive analysis, including 1D and 2D nuclear magnetic resonance (NMR) spectroscopy, and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS). Their absolute configuration was confirmed by single-crystal X-ray diffraction analyses using the anomalous scattering of Cu Kα radiation. All of the isolated compounds were tested for activity against phytopathogenic fungi and nematodes. Compounds 2 and 3 showed antifungal activity and compound 2 showed weak nematicidal activity.
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Antifúngicos/farmacología , Antinematodos/farmacología , Diterpenos/química , Diterpenos/aislamiento & purificación , Saccharomycetales/química , Antifúngicos/química , Antinematodos/química , Cristalografía por Rayos X , Diterpenos/farmacología , Endófitos/química , Endófitos/fisiología , Huperzia/microbiología , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Conformación Molecular , Saccharomycetales/fisiología , Espectrometría de Masa por Ionización de ElectrosprayRESUMEN
Plant virus coat proteins (CPs) play a fundamental role in protection of genomic RNAs, virion assembly, and viral movement. Although phosphorylation of several CPs during virus infection have been reported, little information is available about CP phosphorylation of the spherical RNA plant viruses. Here, we demonstrate that the CP of Beet black scorch virus (BBSV), a member of the genus Necrovirus, can be phosphorylated at threonine-41 (T41) by cAMP-dependent protein kinase (PKA)-like kinase in vivo and in vitro. Mutant viruses containing a T41A non-phosphorylatable alanine substitution, and a T41E glutamic acid substitution to mimic threonine phosphorylation were able to replicate but were unable to move systemically in Nicotiana benthamiana. Interestingly, the T41A and T41E mutants generated unstable 17 nm virus-like particles that failed to package viral genomic (g) RNA, compared with wild-type BBSV with 30 nm virions during viral infection in N. benthamiana. Further analyses showed that the T41 mutations had little effect on the gRNA-binding activity of the CP. Therefore, we propose a model whereby CP phosphorylation plays an essential role in long-distance movement of BBSV that involves formation of stable virions.
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Proteínas de la Cápside/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Virión/metabolismo , Ensamble de Virus , Alanina/genética , Alanina/metabolismo , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Beta vulgaris/virología , Proteínas de la Cápside/genética , Immunoblotting , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Mutación , Fosforilación , Enfermedades de las Plantas/virología , Virus de Plantas/genética , Virus de Plantas/metabolismo , Virus de Plantas/patogenicidad , Homología de Secuencia de Aminoácido , Treonina/genética , Treonina/metabolismo , Nicotiana/virología , Virión/genética , Virión/ultraestructura , Virulencia/genéticaRESUMEN
In most studies regarding the improving or therapeutical effects induced by enriched environment (EE), EE was performed after the stress treatment or in patients with certain diseases. In the current study, the effects of chronic restraint stress (6h/day) in mice living in an enriched environment or standard environment (SE) were tested. Mice were randomly divided into 4 groups: non-stressed or stressed mice housed in SE or EE conditions (SE, stress+SE, EE, stress+EE). Prepulse inhibition (PPI) of startle was tested after the 2 weeks or 4 weeks stress and/or EE treatment and 1 or 2 weeks withdrawal from the 4 weeks treatment. After the 4 weeks treatment, spatial recognition memory in Y-maze was also tested. The results showed that EE increased PPI in stressed and non-stressed mice after 2 weeks treatment. No effect of EE on PPI was found after the 4 weeks treatment. 4 weeks chronic restraint stress increased PPI in mice housed in standard but not EE conditions. Stressed mice showed deficits on the 1h delay version of the Y-maze which could be prevented by living in an enriched environment. Our results indicated that living in an enriched environment reversed the impairing effects of chronic restraint stress on spatial recognition memory. However, EE did not change the effects of stress on PPI.
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Ambiente , Aprendizaje por Laberinto/fisiología , Inhibición Neural/fisiología , Reconocimiento en Psicología/fisiología , Estrés Psicológico/fisiopatología , Estrés Psicológico/terapia , Estimulación Acústica/efectos adversos , Análisis de Varianza , Animales , Peso Corporal/fisiología , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos ICR , Distribución Aleatoria , Reflejo de Sobresalto/fisiología , Restricción Física/métodos , Factores de TiempoRESUMEN
Ca2+-calmodulin (Ca2+-CaM) is a critical molecule that mediates cellular functions by interacting with various metabolic and signaling pathways. However, the protein expression patterns and accompanying serial cytological responses in Ca2+-CaM signaling deficiency remain enigmatic. Here, we provide a global analysis of the cytological responses and significant alterations in protein expression profiles after trifluoperazine treatment in Picea meyeri, which abrogates Ca2+-CaM signaling. Ninety-three differentially displayed proteins were identified by comparative proteomics at different development stages and were assigned to different functional categories closely related to tip growth machinery. The inhibition of Ca2+-CaM signaling rapidly induced an increase in extracellular Ca2+ influx, resulting in dramatically increased cytosolic Ca2+ concentrations and ultrastructural abnormalities in organelles as the primary responses. Secondary and tertiary alterations included actin filament depolymerization, disrupted patterns of endocytosis and exocytosis, and cell wall remodeling, ultimately resulting in perturbed pollen tube extension. In parallel with these cytological events, time-course experiments revealed that most differentially expressed proteins showed time-dependent quantitative changes (i.e. some signaling proteins and proteins involved in organelle functions and energy production changed first, followed by alterations in proteins related to cytoskeletal organization, secretory pathways, and polysaccharide synthesis). Taken together, Ca2+-CaM dysfunction induced serial cytological responses and temporal changes in protein expression profiles, indicating the pivotal role of Ca2+-CaM in the regulation of tip growth machinery.
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Calcio/metabolismo , Calmodulina/metabolismo , Picea/metabolismo , Polen/fisiología , Proteoma , Actinas/efectos de los fármacos , Actinas/metabolismo , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Arabidopsis/metabolismo , Citosol/metabolismo , Citosol/ultraestructura , Evolución Molecular , Germinación , Picea/efectos de los fármacos , Picea/genética , Proteínas de Plantas/efectos de los fármacos , Proteínas de Plantas/metabolismo , Polen/efectos de los fármacos , Polen/crecimiento & desarrollo , Transducción de Señal , Trifluoperazina/farmacologíaRESUMEN
Ca (2+) is an essential ion in the control of pollen germination and tube growth. However, the control of pollen tube development by Ca (2+) signaling and its interactions with cytoskeletal components, energy-providing pathways, and cell-expansion machinery remain elusive. Here, we used nifedipine (Nif) to study Ca (2+) functions in differential protein expression and other cellular processes in Pinus bungeana pollen tube growth. Proteomics analysis indicated that 50 proteins showed differential expression with varying doses of Nif. Thirty-four of these were homologous to previously reported proteins and were classified into different functional categories closely related to tip-growth machinery. Blocking the L-type Ca (2+) channel with Nif in the pollen tube membrane induced several early alterations within a short time, including a reduction of extracellular Ca (2+) influx and a subsequently dramatic decrease in cytosolic free Ca (2+) concentration ([Ca (2+)] c), concomitant with ultrastructural abnormalities and changes in the abundance of proteins involved in energy production and signaling. Secondary alterations included actin filament depolymerization, disrupted patterns of endocytosis/exocytosis, and cell wall remodeling, along with changes in the proteins involved in these processes. These results suggested that extracellular Ca (2+) influx was necessary for the maintenance of the typical tip-focused [Ca (2+)] c gradient in the P. bungeana pollen tube, and that reduced adenosine triphosphate production (ATP), depolymerization of the cytoskeleton, and abnormal endocytosis/exocytosis, together with enhanced rigidity of cell walls, were responsible for the growth arrest observed in pollen tubes treated with Nif.
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Calcio/metabolismo , Pinus , Proteínas de Plantas/análisis , Tubo Polínico/química , Tubo Polínico/crecimiento & desarrollo , Proteoma/análisis , Actinas/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Pared Celular/metabolismo , Pared Celular/ultraestructura , Células Cultivadas , Citoesqueleto/metabolismo , Metabolismo Energético , Colorantes Fluorescentes/metabolismo , Nifedipino/farmacología , Compuestos Orgánicos/metabolismo , Pinus/anatomía & histología , Pinus/química , Pinus/fisiología , Polen/citología , Polen/metabolismo , Tubo Polínico/efectos de los fármacos , Tubo Polínico/ultraestructuraRESUMEN
To investigate roles of the actin cytoskeleton in growth of the pollen tube of Picea meyeri, we used the actin polymerization inhibitor latrunculin B (LATB) under quantitatively controlled conditions. At low concentrations, LATB inhibited polymerization of the actin cytoskeleton in the growing pollen tube, which rapidly inhibited tip growth. The proteomic approach was used to analyse protein expression-profile changes during pollen germination and subsequent pollen-tube development with disturbed organization of the actin cytoskeleton. Two-dimensional electrophoresis and staining with Coomassie Brilliant Blue revealed nearly 600 protein spots. A total of 84 of these were differentially displayed at different hours with varying doses of LATB, and 53 upregulated or downregulated proteins were identified by mass spectrometry. These proteins were grouped into distinct functional categories including signalling, actin cytoskeleton organization, cell expansion and carbohydrate metabolism. Moreover, actin disruption affected the morphology of Golgi stacks, mitochondria and amyloplasts, along with a differential expression of proteins involved in their functions. These findings provide new insights into the multifaceted mechanism of actin cytoskeleton functions and its interaction with signalling, cell-expansion machinery and energy-providing pathways.