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1.
Sci Rep ; 10(1): 20255, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33219240

RESUMO

The majority of genes encoding photosynthesis-associated proteins in the nucleus are induced by light during photomorphogenesis, allowing plants to establish photoautotrophic growth. Therefore, optimizing the protein import apparatus of plastids, designated as the translocon at the outer and inner envelope membranes of chloroplast (TOC-TIC) complex, upon light exposure is a prerequisite to the import of abundant nuclear-encoded photosynthesis-associated proteins. However, the mechanism that coordinates the optimization of the TOC-TIC complex with the expression of nuclear-encoded photosynthesis-associated genes remains to be characterized in detail. To address this question, we investigated the mechanism by which plastid protein import is regulated by light during photomorphogenesis in Arabidopsis. We found that the albino plastid protein import2 (ppi2) mutant lacking Toc159 protein import receptors have active photoreceptors, even though the mutant fails to induce the expression of photosynthesis-associated nuclear genes upon light illumination. In contrast, many TOC and TIC genes are rapidly induced by blue light in both WT and the ppi2 mutant. We uncovered that this regulation is mediated primarily by cryptochrome 1 (CRY1). Furthermore, deficiency of CRY1 resulted in the decrease of some TOC proteins in vivo. Our results suggest that CRY1 plays key roles in optimizing the content of the TOC-TIC apparatus to accommodate the import of abundant photosynthesis-associated proteins during photomorphogenesis.

2.
Elife ; 92020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32894222

RESUMO

Actin filaments and microtubules create diverse cellular protrusions, but intermediate filaments, the strongest and most stable cytoskeletal elements, are not known to directly participate in the formation of protrusions. Here we show that keratin intermediate filaments directly regulate the morphogenesis of microridges, elongated protrusions arranged in elaborate maze-like patterns on the surface of mucosal epithelial cells. We found that microridges on zebrafish skin cells contained both actin and keratin filaments. Keratin filaments stabilized microridges, and overexpressing keratins lengthened them. Envoplakin and periplakin, plakin family cytolinkers that bind F-actin and keratins, localized to microridges, and were required for their morphogenesis. Strikingly, plakin protein levels directly dictate microridge length. An actin-binding domain of periplakin was required to initiate microridge morphogenesis, whereas periplakin-keratin binding was required to elongate microridges. These findings separate microridge morphogenesis into distinct steps, expand our understanding of intermediate filament functions, and identify microridges as protrusions that integrate actin and intermediate filaments.

3.
Sci Rep ; 10(1): 2353, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-32047175

RESUMO

To improve the photosynthetic performance of C3 plants, installing cyanobacterial bicarbonate transporters to the chloroplast inner envelope membrane (IEM) has been proposed for years. In our previous study, we successfully introduced chimeric cyanobacterial sodium-dependent bicarbonate transporters, BicA or SbtA, to the chloroplast IEM of Arabidopsis. However, the installation of authentic BicA and SbtA to the chloroplast IEM has not been achieved yet. In this study, we examined whether or not tobacco etch virus (TEV) protease targeted within chloroplasts can cleave chimeric proteins and produce authentic bicarbonate transporters. To this end, we constructed a TEV protease that carried the transit peptide and expressed it with chimeric BicA or SbtA proteins containing a TEV cleavage site in planta. Chimeric proteins were cleaved only when the TEV protease was co-expressed. The authentic forms of hemagglutinin-tagged BicA and SbtA were detected in the chloroplast IEM. In addition, cleavage of chimeric proteins at the TEV recognition site seemed to occur after the targeting of chimeric proteins to the chloroplast IEM. We conclude that the cleavage of chimeric proteins within chloroplasts is an efficient way to install authentic bicarbonate transporters to the chloroplast IEM. Furthermore, a similar approach can be applied to other bacterial plasma membrane proteins.


Assuntos
Arabidopsis/genética , Proteínas de Bactérias/metabolismo , Cloroplastos/metabolismo , Simportadores de Sódio-Bicarbonato/metabolismo , Proteínas de Bactérias/genética , Cloroplastos/genética , Peptídeo Hidrolases/metabolismo , Potyvirus/enzimologia , Engenharia de Proteínas/métodos , Proteólise , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Simportadores de Sódio-Bicarbonato/genética , Transgenes , Proteínas Virais/metabolismo
4.
Plant Physiol ; 180(2): 743-756, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30918084

RESUMO

Cone thermogenesis is a widespread phenomenon in cycads and may function to promote volatile emissions that affect pollinator behavior. Given their large population size and intense and durable heat-producing effects, cycads are important organisms for comprehensive studies of plant thermogenesis. However, knowledge of mitochondrial morphology and function in cone thermogenesis is limited. Therefore, we investigated these mitochondrial properties in the thermogenic cycad species Cycas revoluta Male cones generated heat even in cool weather conditions. Female cones produced heat, but to a lesser extent than male cones. Ultrastructural analyses of the two major tissues of male cones, microsporophylls and microsporangia, revealed the existence of a population of mitochondria with a distinct morphology in the microsporophylls. In these cells, we observed large mitochondria (cross-sectional area of 2 µm2 or more) with a uniform matrix density that occupied >10% of the total mitochondrial volume. Despite the size difference, many nonlarge mitochondria (cross-sectional area <2 µm2) also exhibited a shape and a matrix density similar to those of large mitochondria. Alternative oxidase (AOX) capacity and expression levels in microsporophylls were much higher than those in microsporangia. The AOX genes expressed in male cones revealed two different AOX complementary DNA sequences: CrAOX1 and CrAOX2 The expression level of CrAOX1 mRNA in the microsporophylls was 100 times greater than that of CrAOX2 mRNA. Collectively, these results suggest that distinctive mitochondrial morphology and CrAOX1-mediated respiration in microsporophylls might play a role in cycad cone thermogenesis.


Assuntos
Cycadopsida/enzimologia , Cycadopsida/fisiologia , Mitocôndrias/enzimologia , Proteínas Mitocondriais/metabolismo , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo , Pólen/enzimologia , Termogênese , Respiração Celular , Cycadopsida/genética , Cycadopsida/ultraestrutura , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Mitocôndrias/ultraestrutura , Membranas Mitocondriais/metabolismo , Especificidade de Órgãos/genética , Pólen/ultraestrutura , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Temperatura
5.
Front Plant Sci ; 8: 310, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28360917

RESUMO

Plastids are DNA-containing organelles and can have unique differentiation states depending on age, tissue, and environment. Plastid biogenesis is optimized by bidirectional communication between plastids and the nucleus. Import of nuclear-encoded proteins into plastids serves as anterograde signals and vice versa, plastids themselves send retrograde signals to the nucleus, thereby controlling de novo synthesis of nuclear-encoded plastid proteins. Recently, it has become increasingly evident that the ubiquitin-proteasome system regulates both the import of anterograde plastid proteins and retrograde signaling from plastids to the nucleus. Targets of ubiquitin-proteasome regulation include unimported chloroplast precursor proteins in the cytosol, protein translocation machinery at the chloroplast surface, and transcription factors in the nucleus. This review will focus on the mechanism through which the ubiquitin-proteasome system optimizes plastid biogenesis and plant development through the regulation of nuclear-plastid interactions.

6.
Plant Physiol ; 173(1): 524-535, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27821720

RESUMO

Arabidopsis (Arabidopsis thaliana) GOLDEN2-LIKE (GLK) transcription factors promote chloroplast biogenesis by regulating the expression of photosynthesis-related genes. Arabidopsis GLK1 is also known to participate in retrograde signaling from chloroplasts to the nucleus. To elucidate the mechanism by which GLK1 is regulated in response to plastid signals, we biochemically characterized Arabidopsis GLK1 protein. Expression analysis of GLK1 protein indicated that GLK1 accumulates in aerial tissues. Both tissue-specific and Suc-dependent accumulation of GLK1 were regulated primarily at the transcriptional level. In contrast, norflurazon- or lincomycin-treated gun1-101 mutant expressing normal levels of GLK1 mRNA failed to accumulate GLK1 protein, suggesting that plastid signals directly regulate the accumulation of GLK1 protein in a GUN1-independent manner. Treatment of the glk1glk2 mutant expressing functional GFP-GLK1 with a proteasome inhibitor, MG-132, induced the accumulation of polyubiquitinated GFP-GLK1. Furthermore, the level of endogenous GLK1 in plants with damaged plastids was partially restored when those plants were treated with MG-132. Collectively, these data indicate that the ubiquitin-proteasome system participates in the degradation of Arabidopsis GLK1 in response to plastid signals.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Plastídeos/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Leupeptinas/farmacologia , Plantas Geneticamente Modificadas , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/farmacologia , Fatores de Transcrição/genética
7.
Sci Rep ; 6: 29440, 2016 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-27389636

RESUMO

Floral thermogenesis has been found in dozens of primitive seed plants and the reproductive organs in these plants produce heat during anthesis. Thus, characterization of the molecular mechanisms underlying flowering is required to fully understand the role of thermogenesis, but this aspect of thermogenic plant development is largely unknown. In this study, extensive database searches and cloning experiments suggest that thermogenic skunk cabbage (Symplocarpus renifolius), which is a member of the family Araceae, possesses two genes encoding phosphatidyl ethanolamine-binding proteins (PEBP), FLOWERING LOCUS T (SrFT) and MOTHER OF FT AND TFL1 (SrMFT). Functional analyses of SrFT and SrMFT in Arabidopsis indicate that SrFT promotes flowering, whereas SrMFT does not. In S. renifolius, the stage- and tissue-specific expression of SrFT was more evident than that of SrMFT. SrFT was highly expressed in flowers and leaves and was mainly localized in fibrovascular tissues. In addition, microarray analysis revealed that, within floral tissues, SrFT was co-regulated with the genes associated with cellular respiration and mitochondrial function, including ALTERNATIVE OXIDASE gene proposed to play a major role in floral thermogenesis. Taken together, these data suggest that, among the PEBP genes, SrFT plays a role in flowering and floral development in the thermogenic skunk cabbage.


Assuntos
Araceae/crescimento & desenvolvimento , Proteína de Ligação a Fosfatidiletanolamina/genética , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Análise de Sequência de DNA/métodos , Araceae/genética , Araceae/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Especificidade de Órgãos , Filogenia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
8.
Genes Cells ; 21(7): 728-39, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27353389

RESUMO

Lrrc6 encodes a cytoplasmic protein that is expressed specifically in cells with motile cilia including the node, trachea and testes of the mice. A mutation of Lrrc6 has been identified in human patients with primary ciliary dyskinesia (PCD). Mutant mice lacking Lrrc6 show typical PCD defects such as hydrocephalus and laterality defects. We found that in the absence of Lrrc6, the morphology of motile cilia remained normal, but their motility was completely lost. The 9 + 2 arrangement of microtubules remained normal in Lrrc6(-/-) mice, but the outer dynein arms (ODAs), the structures essential for the ciliary beating, were absent from the cilia. In the absence of Lrrc6, ODA proteins such as DNAH5, DNAH9 and IC2, which are assembled in the cytoplasm and transported to the ciliary axoneme, remained in the cytoplasm and were not transported to the ciliary axoneme. The IC2-IC1 interaction, which is the first step of ODA assembly, was normal in Lrrc6(-/-) mice testes. Our results suggest that ODA proteins may be transported from the cytoplasm to the cilia by an Lrrc6-dependent mechanism.


Assuntos
Cílios/genética , Síndrome de Kartagener/genética , Proteínas/genética , Animais , Dineínas do Axonema/genética , Axonema/genética , Axonema/patologia , Cílios/patologia , Citoplasma/genética , Citoplasma/metabolismo , Proteínas do Citoesqueleto , Modelos Animais de Doenças , Dineínas/genética , Humanos , Síndrome de Kartagener/patologia , Camundongos , Camundongos Transgênicos , Mutação
9.
Front Plant Sci ; 7: 16, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26870048

RESUMO

Installation of cyanobacterial bicarbonate transporters to the inner envelope membrane (IEM) of chloroplasts in C3 plants has been thought to improve photosynthetic performance. However, the method to deliver cyanobacterial bicarbonate transporters to the chloroplast IEM remains to be established. In this study, we provide evidence that the cyanobacterial bicarbonate transporters, BicA and SbtA, can be specifically installed into the chloroplast IEM using the chloroplast IEM targeting signal in conjunction with the transit peptide. We fused the transit peptide and the mature portion of Cor413im1, whose targeting mechanism to the IEM has been characterized in detail, to either BicA or SbtA isolated from Synechocystis sp. PCC6803. Among the seven chimeric constructs tested, we confirmed that four chimeric bicarbonate transporters, designated as BicAI, BicAII, SbtAII, and SbtAIII, were expressed in Arabidopsis. Furthermore, these chimeric transporters were specifically targeted to the chloroplast IEM. They were also resistant to alkaline extraction but can be solubilized by Triton X-100, indicating that they are integral membrane proteins in the chloroplast IEM. One of the transporters, BicA, could reside in the chloroplast IEM even after removal of the IEM targeting signal. Taken together, our results indicate that the addition of IEM targeting signal, as well as the transit peptide, to bicarbonate transporters allows us to efficiently target nuclear-encoded chimeric bicarbonate transporters to the chloroplast IEM.

10.
J Exp Bot ; 65(18): 5257-65, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25013120

RESUMO

The inner envelope membrane (IEM) of the chloroplast plays crucial roles in forming an osmotic barrier and controlling metabolite exchange between the organelle and the cytosol. The IEM therefore harbours a number of membrane proteins and requires the import and integration of these nuclear-encoded proteins for its biogenesis. Recent studies have demonstrated that the transmembrane segment of single-spanning IEM proteins plays key roles in determining their IEM localization. However, few studies have focused on the molecular mechanisms by which polytopic membrane proteins are targeted to the IEM. In this study, we investigated the targeting mechanism of polytopic IEM proteins using the protein Cor413im1 as a model substrate. Cor413im1 does not utilize a soluble intermediate for its targeting to the IEM. Furthermore, we show that the putative fifth transmembrane segment of Cor413im1 is necessary for its targeting to the IEM. The C-terminal portion containing this transmembrane segment is also able to deliver Cor413im1 protein to the IEM. However, the fifth transmembrane segment of Cor413im1 itself is insufficient to target a fusion protein to the IEM. These data suggest that the targeting of polytopic membrane proteins to the chloroplast IEM in vivo involves multiple transmembrane segments and that chloroplasts have evolved a unique mechanism for the integration of polytopic proteins to the IEM.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Cloroplastos/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de Membrana/metabolismo , Transporte Proteico/fisiologia
11.
Nihon Ronen Igakkai Zasshi ; 50(6): 788-96, 2013.
Artigo em Japonês | MEDLINE | ID: mdl-24622227

RESUMO

AIM: The objective of the present study was to evaluate the long-term effectiveness of an exercise program in modifying the exercise behavior of the community-dwelling elderly subjects. METHODS: This study was a single-blinded randomized controlled trial. The subjects included 52 males and 65 females 65 years of age or over who were randomly assigned to an exercise-intervention group or a health-education group. The stages of change in exercise behavior were evaluated before and one-year after the intervention period. The subjects' physical function (muscle strength, balance, walking speed) and self-efficacy in each domain of the physical function were measured during the intervention period. RESULTS: There were no significant differences in the stages of change before the intervention between the two groups. Significant differences in the stages of change were observed in "relapse" of stages at two points in time between the two groups (p<.01). A logistic regression analysis showed that "progression" of stages was associated with improvements in the timed up and go test (AOR 2.7; 95% CI 1.3-5.8) and sit and reach (AOR 1.14; 95%CI 1.0-1.3), while "relapse" of stages was associated with the group allocation (AOR 4.6; 95%CI 1.1-18.8), self-efficacy in "Walking" (AOR 1.54; 95%CI 1.0-2.3) and "Stair climbing" (AOR 0.68; 95%CI 0.5-0.9) with respect to physical activity during the intervention period. CONCLUSIONS: The results suggest that exercise intervention in community-dwelling elderly subjects is effective in preventing "relapse" of exercise behavior over long periods.


Assuntos
Exercício Físico , Autoeficácia , Idoso , Exercício Físico/psicologia , Feminino , Humanos , Vida Independente , Masculino , Força Muscular , Caminhada
12.
Biosci Biotechnol Biochem ; 76(10): 1990-2, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23047088

RESUMO

Skunk cabbage (Symplocarpus renifolius) spadices contain abundant transcripts for cysteine protease (CP). From thermogenic spadices, we isolated SrCPA, a highly expressed CP gene that encoded a papain-type CP. SrCPA is structurally similar to other plant CPs, including the senescence-associated CPs found in aroids. The expression of SrCPA increased during floral development, and was observed in all floral tissues except for the stamens.


Assuntos
Araceae/enzimologia , Araceae/genética , Regulação da Expressão Gênica de Plantas , Papaína/genética , Sequência de Aminoácidos , Araceae/crescimento & desenvolvimento , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Dados de Sequência Molecular , Papaína/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
13.
J Exp Bot ; 63(1): 251-60, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21926093

RESUMO

Retrograde signalling from the plastid to the nucleus, also known as plastid signalling, plays a key role in coordinating nuclear gene expression with the functional state of plastids. Inhibitors that cause plastid dysfunction have been suggested to generate specific plastid signals related to their modes of action. However, the molecules involved in plastid signalling remain to be identified. Genetic studies indicate that the plastid-localized pentatricopeptide repeat protein GUN1 mediates signalling under several plastid signalling-related conditions. To elucidate further the nature of plastid signals, investigations were carried out to determine whether different plastid signal-inducing treatments had similar effects on plastids and on nuclear gene expression. It is demonstrated that norflurazon and lincomycin treatments and the plastid protein import2-2 (ppi2-2) mutation, which causes a defect in plastid protein import, all resulted in similar changes at the gene expression level. Furthermore, it was observed that these three treatments resulted in defective RNA editing in plastids. This defect in RNA editing was not a secondary effect of down-regulation of pentatricopeptide repeat protein gene expression in the nucleus. The results indicate that these three treatments, which are known to induce plastid signals, affect RNA editing in plastids, suggesting an unprecedented link between plastid signalling and RNA editing.


Assuntos
Plastídeos , Transdução de Sinais , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Genes de Plantas , Mutação , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição/genética , Transcrição Genética
14.
Arch Gerontol Geriatr ; 54(2): e175-80, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22100108

RESUMO

Although it is more important to assess the muscular power of the lower extremities than the strength, no simplified method for doing so has been found. The aim of this study was to assess the validity of the assessment of the angular velocity of KE using a gyroscope. Participants included 105 community-dwelling older people (55 women, 50 men, age ± standard deviation (SD) 75±5.3). Pearson correlation coefficients and Spearman rank-correlation coefficients were used to examine the relationships between the angular velocity of KE and functional performance measurements, a self-efficacy scale and health-related quality of life (HRQOL). The data from the gyroscope were significantly correlated with some physical functions such as muscle strength (r=0.304, p<0.01), and walking velocity (r=0.543, p<0.001). In addition, the joint angular velocity was significantly correlated with self-efficacy (r=0.219-0.329, p<0.01-0.05) and HRQOL (r=0.207-0.359, p<0.01-0.05). The absolute value of the correlation coefficient of angular velocity tended to be greater than that of the muscle strength for mobility functions such as walking velocity and the timed-up-and-go (TUG) test. In conclusion, it was found that the assessment of the angular velocity of the knee joint using a gyroscope could be a feasible and meaningful measurement in the geriatrics field.


Assuntos
Articulação do Joelho/fisiologia , Força Muscular/fisiologia , Idoso , Feminino , Avaliação Geriátrica , Humanos , Masculino , Movimento/fisiologia , Equipamentos Ortopédicos , Ortopedia/métodos , Aptidão Física , Qualidade de Vida , Reprodutibilidade dos Testes , Autoeficácia
15.
Plant Cell Environ ; 35(3): 554-66, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21955303

RESUMO

Floral thermogenesis has been described in several plant species. Because of the lack of comprehensive gene expression profiles in thermogenic plants, the molecular mechanisms by which floral thermogenesis is regulated remain to be established. We examined the gene expression landscape of skunk cabbage (Symplocarpus renifolius) during thermogenic and post-thermogenic stages and identified expressed sequence tags from different developmental stages of the inflorescences using super serial analysis of gene expression (SuperSAGE). In-depth analysis suggested that cellular respiration and mitochondrial functions are significantly enhanced during the thermogenic stage. In contrast, genes involved in stress responses and protein degradation were significantly up-regulated during post-thermogenic stages. Quantitative comparisons indicated that the expression levels of genes involved in cellular respiration were higher in thermogenic spadices than in Arabidopsis inflorescences. Thermogenesis-associated genes seemed to be expressed abundantly in the peripheral tissues of the spadix. Our results suggest that cellular respiration and mitochondrial metabolism play key roles in heat production during floral thermogenesis. On the other hand, vacuolar cysteine protease and other degradative enzymes seem to accelerate senescence and terminate thermogenesis in the post-thermogenic stage.


Assuntos
Araceae/genética , Flores/fisiologia , Mitocôndrias/metabolismo , Temperatura , Vacúolos/metabolismo , Araceae/fisiologia , Respiração Celular , Análise por Conglomerados , Etiquetas de Sequências Expressas , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , RNA de Plantas/genética , Transcriptoma
16.
Int Rev Cell Mol Biol ; 290: 167-204, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21875565

RESUMO

Plastids are a diverse group of organelles found in plants and some parasites. Because genes encoding plastid proteins are divided between the nuclear and plastid genomes, coordinated expression of genes in two separate genomes is indispensable for plastid function. To coordinate nuclear gene expression with the functional or metabolic state of plastids, plant cells have acquired a retrograde signaling pathway from plastid to nucleus, also known as the plastid signaling pathway. To date, several metabolic processes within plastids have been shown to affect the expression of nuclear genes. Recent progress in this field has also revealed that the plastid signaling pathway interacts and shares common components with other intracellular signaling pathways. This review summarizes our current knowledge on retrograde signaling from plastid to nucleus in plant cells and its role in plant growth and development.


Assuntos
Núcleo Celular/metabolismo , Células Vegetais/metabolismo , Plastídeos/metabolismo , Transdução de Sinais , Núcleo Celular/genética , Desenvolvimento Vegetal , Plantas/metabolismo , Plastídeos/genética , Transdução de Sinais/efeitos dos fármacos
17.
Allergol Int ; 60(1): 97-101, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21252619

RESUMO

A 13-year-old girl who had had pollinosis since the age of eight began to experience itching of the ears and vomiting after eating fresh fruits such as peach, apple and watermelon. This occurred at 10 years of age. The girl displayed positive reactions to six kinds of pollens, eleven kinds of fruits, numerous vegetables and to recombinant: rBet v2 present in specific IgE antibodies. She also reacted positively to several pollens, fruits and rBet v2 in the skin prick test. In the component-resolved diagnosis (CRD) using microarray technology, she also tested positive for profilin, a pan-allergen among plants. It is reported that profilin cross-reacts between pollen, fruits, vegetables and latex. From these results, we concluded that the allergic reactions to multiple kinds of foodstuff and pollens observed in this subject were due to cross-reactivity induced by profilin. Our results demonstrate that CRD by microarray is a reliable test in the diagnosis of PFAS.


Assuntos
Alérgenos/imunologia , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/imunologia , Pólen/imunologia , Rinite Alérgica Sazonal/diagnóstico , Rinite Alérgica Sazonal/imunologia , Adolescente , Reações Cruzadas/imunologia , Feminino , Humanos , Imunoglobulina E/sangue , Técnicas de Imunoadsorção , Análise Serial de Proteínas , Testes Cutâneos , Síndrome
18.
Plant Cell Physiol ; 51(11): 1847-53, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20889507

RESUMO

Plastids, found in plants and some parasites, are of endosymbiotic origin. The best-characterized plastid is the plant cell chloroplast. Plastids provide essential metabolic and signaling functions, such as the photosynthetic process in chloroplasts. However, the role of plastids is not limited to production of metabolites. Plastids affect numerous aspects of plant growth and development through biogenesis, varying functional states and metabolic activities. Examples include, but are not limited to, embryogenesis, leaf development, gravitropism, temperature response and plant-microbe interactions. In this review, we summarize the versatile roles of plastids in plant growth and development.


Assuntos
Desenvolvimento Vegetal , Plastídeos , Fotossíntese , Plantas/embriologia , Plantas/metabolismo , Sementes/crescimento & desenvolvimento , Transdução de Sinais
19.
Planta ; 231(1): 121-30, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19859730

RESUMO

Thermogenesis during the blooming of inflorescence is found in several but not all aroids. To understand what is critical for thermogenesis, we investigated the difference between thermogenic and non-thermogenic skunk cabbages (Symplocarpus renifolius and Lysichiton camtschatcensis), which are closely related in morphology and phylogeny. Critical parameters of mitochondrial biogenesis, including density, respiratory activity, and protein expression were compared between these two species. Mitochondrial density, respiratory activity, and the amount of alternative oxidase (AOX) in L. camtschatcensis spadix mitochondria were lower than in S. renifolius spadix mitochondria, while the level of uncoupling protein (UCP) was higher. AOX and UCP mRNAs in L. camtschatcensis were constitutively expressed in various tissues, such as the spadix, the spathe, the stalk, and the leaves. cDNA encoding two putative thermogenic proteins, AOX and UCP were isolated from L. camtschatcensis, and their primary structure was analyzed by multiple alignment and phylogenetic tree reconstruction. AOX and UCP protein of two the skunk cabbage species are closely related in structure, compared with other isoforms in thermogenic plants. Our results suggest that mitochondrial density, respiratory activity, and protein expression, rather than the primary structure of AOX or UCP proteins, may play critical roles in thermogenesis in plants.


Assuntos
Araceae/fisiologia , Regulação da Expressão Gênica de Plantas , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Araceae/citologia , Araceae/enzimologia , Araceae/genética , Respiração Celular , Perfilação da Expressão Gênica , Canais Iônicos/química , Canais Iônicos/genética , Canais Iônicos/metabolismo , Mitocôndrias/enzimologia , Proteínas Mitocondriais/química , Proteínas Mitocondriais/genética , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Oxirredutases/química , Oxirredutases/genética , Oxirredutases/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Temperatura , Proteína Desacopladora 1
20.
J Exp Bot ; 60(13): 3909-22, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19640927

RESUMO

Sex-dependent thermogenesis during reproductive organ development in the inflorescence is a characteristic feature of some of the protogynous arum species. One such plant, skunk cabbage (Symplocarpus renifolius), can produce massive heat during the female stage but not during the subsequent male stage in which the stamen completes development, the anthers dehisce, and pollen is released. Unlike other thermogenic species, skunk cabbage belongs to the bisexual flower group. Although recent studies have identified the spadix as the thermogenic organ, it remains unclear how individual tissues or intracellular structures are involved in thermogenesis. In this study, reproductive organ development and organelle biogenesis were examined during the transition from the female to the male stage. During the female stage, the stamens exhibit extensive structural changes including changes in organelle structure and density. They accumulate high levels of mitochondrial proteins, including possible thermogenic factors, alternative oxidase, and uncoupling protein. By contrast, the petals and pistils do not undergo extensive changes during the female stage. However, they contain a larger number of mitochondria than during the male stage in which they develop large cytoplasmic vacuoles. Comparison between female and male spadices suggests that mitochondrial number rather than their level of activity correlates with thermogenesis. Their spadices, even in the male, contain a larger amount of mitochondria that had greater oxygen consumption, compared with non-thermogenic plants. Taken together, our data suggest that the extensive maturation process in stamens produces massive heat through increased metabolic activities. The possible mechanisms by which petal and pistil metabolism may affect thermogenesis are also discussed.


Assuntos
Araceae/crescimento & desenvolvimento , Araceae/fisiologia , Organelas/fisiologia , Araceae/química , Araceae/genética , Flores/química , Flores/genética , Flores/crescimento & desenvolvimento , Flores/fisiologia , Temperatura Alta , Organelas/química , Organelas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reprodução
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