Abstract ATHB-8, -9, -14, -15, and IFL1/REV are members of a small homeodomain-leucine zipper family whose genes characterized by expression in the vascular tissue. gene positively regulated auxin (Baima et al., 1995), is considered an early marker procambial cells cambium during regeneration after wounding. Here, we demonstrate that although formation system not affected inathb8 mutants, ectopic ATHB-8 Arabidopsis plants increased production xylem In particular, careful anatomical analysis...

Abstract We provide evidence on the localization, synthesis, transport, and effects of auxin processes occurring late in Arabidopsis thaliana stamen development: anther dehiscence, pollen maturation, preanthesis filament elongation. Expression auxin-sensitive reporter constructs suggests that begin anthers between end meiosis bilocular stage somatic tissues involved first step dehiscence as well microspores junction region filament. In situ hybridizations biosynthetic genes YUC2 YUC6 suggest...

The heavy metal cadmium (Cd) is a widespread environmental contaminant with harmful effects on living cells. In plants, phytochelatin (PC)-dependent Cd detoxification requires that PC–Cd complexes are transported into vacuoles. Here, it shown Arabidopsis thaliana seedlings defective in the ABCC transporter AtABCC3 (abcc3) have an increased sensitivity to different concentrations, and overexpressing (AtABCC3ox) tolerance. cellular distribution of was analysed protoplasts from abcc3 mutants...

Abstract MADS box transcription factors controlling flower development have been isolated and studied in a wide variety of organisms. These studies shown that homologous genes from different species often similar functions. OsMADS18 rice (Oryza sativa) belongs to the phylogenetically defined AP1/SQUA group. The this group functions plant development, like transition vegetative reproductive growth, determination floral organ identity, regulation fruit maturation. In paper we report functional...

Adventitious roots (ARs) are part of the root system in numerous plants, and required for successful micropropagation. In Arabidopsis thaliana primary (PR) lateral (LRs), quiescent centre (QC) stem cell niche meristem controls apical growth with involvement auxin cytokinin. arabidopsis, ARs emerge planta from hypocotyl pericycle, different tissues vitro cultured explants, e.g. endodermis thin layer (TCL) explants. The aim this study was to investigate establishment maintenance QC arabidopsis...

Previous studies demonstrated that expression of the Arabidopsis phytochelatin (PC) biosynthetic gene AtPCS1 in Nicotiana tabacum plants increases Cd tolerance presence exogenous glutathione (GSH). In this paper, over-expressing (AtPCSox lines) has been analysed and differences between tobacco are shown. Based on analysis seedling fresh weight, primary root length, alterations anatomy, evidence is provided that, at relatively low concentrations, AtPCSox lines lower than wild type, while more...

Cadmium (Cd) and arsenic (As), non essential, but toxic, elements for animals plants are frequently present in paddy fields. Oryza sativa L., a staple food at least the half of world population, easily absorbs As Cd by root, this organ pollutants evoke consistent damages, reducing/modifying root system. Auxins key hormones regulating all developmental processes, including organogenesis. Moreover, respond to environmental stresses, such as those caused As, changing levels distribution...

Summary It has been suggested that, in A rabidopsis, auxin controls the timing of anther dehiscence, possibly by preventing premature endothecium lignification. We show here that content anthers peaks before beginning dehiscence and decreases when lignification occurs. auxin‐perception mutants afb1‐3 tir1 afb2 afb3 , occur earlier than wild‐type, gene encoding transcription factor MYB 26, which is required for lignification, over‐expressed specifically at early stages; agreement, 26...

The olive tree lacks dormancy and is low temperature sensitive, with differences in cold tolerance oil quality among genotypes. produced the drupe, unsaturated fatty acids contribute to its quality. aim of present research was investigate relationship development, response, expression acid desaturase (FAD) genes, composition drupes belonging genotypes differing leaf tolerance, but producing good (i.e. non-hardy Moraiolo, semi-hardy Frantoio, hardy Canino). In all genotypes, sensitivity,...

In plant cells, cadmium (Cd) and arsenic (As) exert toxicity mainly by inducing oxidative stress through an imbalance between the production of reactive oxygen species (ROS) nitrogen (RNS), their detoxification. Nitric oxide (NO) is a RNS acting as signalling molecule coordinating development responses, but also inducer, depending on its cellular concentration. Peroxisomes are versatile organelles involved in metabolism signalling, with role redox balance thanks to antioxidant enzymes,...

Overexpression of the proline biosynthetic gene P5CS1 results in early flowering Arabidopsis. However, p5cs1 loss-of-function mutant exhibits a modest delay flowering, suggesting that P5CS2, duplicated present Arabidopsis, may also play role flower transition. In situ mRNA hybridizations and quantitative reverse transcription-polymerase chain reaction (RT-PCR) revealed P5CS2 are expressed at similar levels with same pattern expression vegetative floral shoot apical meristems as well axillary...

The concentrations of three classes polyamines, trichloroacetic acid‐soluble (free), TCA‐soluble conjugated (to small molecules) and TCA‐insoluble macromolecules), was examined during de novo floral vegetative bud formation in thin cell layers Nicotiana tabacum L. cv. Samsun. Explants (consisting 5–6 epidermal, subepidermal parenchyma cells) were excised either from pedicels or stem internodes at the unripe fruit stage cultured on same medium. In former, first formed flower buds appeared day...

The research was focussed on the effects of cadmium (Cd) and arsenic (As), alone or combined, Arabidopsis post-embryonic roots, with attention to quiescent centre formation development in relation auxin homeostasis. To aim, morphological histochemical analyses were carried out seedlings, exposed not Cd and/or As, wild type, transgenic lines useful for monitoring identity, localization cellular influx efflux. Moreover, levels expression YUC6 biosynthetic gene monitored As type seedlings....

To date, almost no information is available in roots and shoots of the model plant Arabidopsis thaliana about hierarchic relationship between metal accumulation, phytohormone levels, glutathione/phytochelatin content, how this relation affects root development. For purpose, specific concentrations cadmium, copper zinc, alone or triple combination, were supplied for 12 days to vitro growing seedlings. The accumulation these metals was measured shoots, a significant competition uptake...

The heterologous expression of AtPCS1 in tobacco plants exposed to arsenic plus cadmium enhances phytochelatin levels, root As/Cd accumulation and pollutants detoxification, but does not prevent cyto-histological damages. High (PC) levels may be involved detoxification both (Cd) (As) numerous plants. Although polluted environments are frequently characterized by As Cd coexistence, how increased PC affect the adaptation entire plant response its cells/tissues a combined contamination needs...

Adventitious roots (ARs) are post-embryonic essential for plant survival and propagation. Indole-3-acetic acid (IAA) is the auxin that controls AR formation; however, its precursor indole-3-butyric (IBA) known to enhance it. Ethylene affects many auxin-dependent processes by affecting IAA synthesis, transport and/or signaling, but role in formation has not been elucidated. This research investigated of ethylene dark-grown Arabidopsis thaliana seedlings, interaction with IAA/IBA. A number...

Indole-3-acetic acid (IAA), and its precursor indole-3-butyric (IBA), control adventitious root (AR) formation in planta. Adventitious roots are also crucial for propagation via cuttings. However, IBA role(s) is/are still far to be elucidated. In Arabidopsis thaliana stem cuttings, 10 μM is more AR-inductive than IAA, and, thin cell layers (TCLs), induces ARs when combined with 0.1 kinetin (Kin). It unknown whether arabidopsis TCLs produce under alone (10 μM) or IAA μM), they contain...

Adventitious roots (ARs) are essential for vegetative propagation. The Arabidopsis thaliana transcription factors SHORT ROOT (SHR) and SCARECROW (SCR) affect primary/lateral root development, but their involvement in AR formation is uncertain. LAX3 AUX1 auxin influx carriers contribute to development. expression regulated by SHR, contributes tip maximum. In contrast, development unknown. Xylogenesis induced plus cytokinin as formation, the genes involved largely Stem thin cell layers (TCLs)...

L. is a worldwide food-crop frequently growing in cadmium (Cd)/arsenic (As) polluted soils, with its root-system as the first target of pollutants. Root-system development involves establishment optimal indole-3-acetic acid (IAA) levels, also requiring conversion IAA natural precursor indole-3-butyric (IBA) into IAA, causing nitric oxide (NO) formation. Nitric stress-signaling molecule. In rice, negative interaction Cd or As endogenous auxin has been demonstrated, some NO protective effects....

Adventitious roots (ARs) are often necessary for plant survival, and essential successful micropropagation. In Arabidopsis thaliana dark-grown seedlings AR-formation occurs from the hypocotyl is enhanced by application of indole-3-butyric acid (IBA) combined with kinetin (Kin). The same IBA + Kin-treatment induces in thin cell layers (TCLs). Auxin main inducer xylogenesis numerous species experimental systems. Xylogenesis competitive to hypocotyls TCLs. Jasmonates (JAs) negatively affect...

Nitric oxide (NO) has signalling roles in plant stress responses. Cadmium (Cd) and arsenic (As) soil pollutants alter development, mainly the root-system, by increasing NO-content, triggering reactive oxygen species (ROS), forming peroxynitrite NO-reaction with superoxide anion. Interactions of NO ROS seem important for tolerance to heavy metal(oid)s, but mechanisms underlying this process remain unclear. Our goal was investigate NO-involvement rice (Oryza sativa L.) root-system after...

The effect of methyl jasmonate (MJ) on de novo shoot formation and polyamine metabolism was investigated in thin layer explants tobacco (Nicotiana tabacum L. cv. Samsun). A relatively low concentration MJ (0.1 microM) enhanced explant fresh weight, but had no the final number shoots per while higher concentrations (1 10 significantly inhibited organogenesis. histological study revealed that, with increasing MJ, meristemoids domes declined incidence cell hypertrophy increased. In cultured...