Programmed cell death (PCD) occurs during vegetative and reproductive plant growth, as typified by autumnal leaf senescence and the terminal differentiation of the endosperm of cereals which provide our major source of food. PCD also occurs in response to environmental stress and pathogen attack, and these inducible PCD forms are intensively studied due their experimental tractability. In general, evidence exists for plant cell death pathways which have similarities to the apoptotic, autophagic and necrotic forms described in yeast and metazoans. Recent research aiming to understand these pathways and their molecular components in plants are reviewed here.
"Dichos procesos tienen que ver con mecanismos propios de diferentes estados de la planta, como, por ejemplo, la muerte de células aleurónicas durante la germi- Figura 5. a) Micrografía del grano que muestra aleurona de las células del endospermo diferenciadas terminalmente llenas de almidón; b) células de xilema diferenciadas; c) senescencia de la hoja de arce. Fuente:  nación (figura 5a); procesos de diferenciación del xilema (figura 5b); la reproducción y el desarrollo floral; diferenciación sexual de plantas hermafroditas en angiospermas  y durante el desarrollo de procesos de senescencia (figura 5c), la cual comienza con disminución de la rapidez fotosintética, caracterizada por una participación muy activa de las vacuolas y procesos de autofagia  "
[Show abstract][Hide abstract] ABSTRACT: La comprensión de los mecanismos de defensa de las plantas permite generar conocimiento
básico para la conservación y el uso de los recursos filogenéticos, así como para
la seguridad alimentaria. Un mecanismo importante en la vida de las plantas es la muerte
celular programada, una especie de suicidio celular, reacción hipersensitiva parecida
a la apoptosis animal. Este proceso les permite a las plantas el desarrollo de múltiples cambios
durante su ciclo biológico, como también la defensa frente al ataque de patógenos y combatir el estrés.
"This gene is proposed to be a negative regulator of the defense mechanism and cell death in barley, as a loss-of-function mutation leads to resistance against biotrophic pathogens such as powdery mildews , . Other MLO proteins have been suggested to act as negative regulators of cell-wall apposition formation during non-host resistance , . Furthermore, MLO has been suggested to be a sensor and effector of cellular redox status . "
[Show abstract][Hide abstract] ABSTRACT: The plant cell cuticle serves as the first barrier protecting plants from mechanical injury and invading pathogens. The cuticle can be breached by cutinase-producing pathogens and the degradation products may activate pathogenesis signals in the invading pathogens. Cuticle degradation products may also trigger the plant's defense responses. Botrytis cinerea is an important plant pathogen, capable of attacking and causing disease in a wide range of plant species. Arabidopsis thaliana shn1-1D is a gain-of-function mutant, which has a modified cuticular lipid composition. We used this mutant to examine the effect of altering the whole-cuticle metabolic pathway on plant responses to B. cinerea attack. Following infection with B. cinerea, the shn1-1D mutant discolored more quickly, accumulated more H2O2, and showed accelerated cell death relative to wild-type (WT) plants. Whole transcriptome analysis of B. cinerea-inoculated shn1-1D vs. WT plants revealed marked upregulation of genes associated with senescence, oxidative stress and defense responses on the one hand, and genes involved in the magnitude of defense-response control on the other. We propose that altered cutin monomer content and composition of shn1-1D plants triggers excessive reactive oxygen species accumulation and release which leads to a strong, unique and uncontrollable defense response, resulting in plant sensitivity and death.
PLoS ONE 07/2013; 8(7):e70146. DOI:10.1371/journal.pone.0070146 · 3.23 Impact Factor
"In plants, the hypersensitive reaction, which can be regarded as a type of cell apoptosis, is induced by the presence of incompatible microbes or various elicitors from microbes. ROS production, the expression of defense genes, and antimicrobial secondary metabolite production are known to be induced during the hypersensitive reaction . A few studies have indicated that fungal elicitors are able to induce cell apoptosis and the production of secondary metabolites, including taxol, artemisinin, and β-thujaplicin, in Taxus chinensis, Artemisia annua, and Cupressus lusitanica, respectively –. "
[Show abstract][Hide abstract] ABSTRACT: Ganoderma lucidum is one of most widely used herbal medicine and functional food in Asia, and ganoderic acids (GAs) are its active ingredients. Regulation of GA biosynthesis and enhancing GA production are critical to using G. lucidum as a medicine. However, regulation of GA biosynthesis by various signaling remains poorly understood. This study investigated the role of apoptosis signaling on GA biosynthesis and presented a novel approach, namely apoptosis induction, to increasing GA production. Aspirin was able to induce cell apoptosis in G. lucidum, which was identified by terminal deoxynucleotidyl transferase mediated dUPT nick end labeling assay positive staining and a condensed nuclear morphology. The maximum induction of lanosta-7,9(11), 24-trien-3α-01-26-oic acid (ganoderic acid 24, GA24) production and total GA production by aspirin were 2.7-fold and 2.8-fold, respectively, after 1 day. Significantly lower levels of GA 24 and total GAs were obtained after regular fungal culture for 1.5 months. ROS accumulation and phosphorylation of Hog-1 kinase, a putative homolog of MAPK p38 in mammals, occurred after aspirin treatment indicating that both factors may be involved in GA biosynthetic regulation. However, aspirin also reduced expression of the squalene synthase and lanosterol synthase coding genes, suggesting that these genes are not critical for GA induction. To the best of our knowledge, this is the first report showing that GA biosynthesis is linked to fungal apoptosis and provides a new approach to enhancing secondary metabolite production in fungi.
PLoS ONE 01/2013; 8(1):e53616. DOI:10.1371/journal.pone.0053616 · 3.23 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.