Riccardo Angelini - Academia.edu (original) (raw)

Papers by Riccardo Angelini

Research paper thumbnail of Cytotoxic effect induced by maize polyamine oxidase in presence of spermine in human cancer cells

Research paper thumbnail of Comparative analysis of the role of the different Arabidopsis polyamine oxidases in plant defense responses to environmental stresses

Research paper thumbnail of Polyamine Catabolism in Arabidopsis Thaliana

Research paper thumbnail of The apoplastic copper amine oxidase AtCuAOβ plays a role in stomatal closure induced by wounding, jasmonate or Microbe Associated Molecular Patterns (MAMPS)

Research paper thumbnail of Arabidopsis N-acetyltransferase activity 2 preferentially acetylates 1,3-diaminopropane and thialysine

Plant Physiology and Biochemistry

Research paper thumbnail of A New Player in Jasmonate-Mediated Stomatal Closure: The Arabidopsis thaliana Copper Amine Oxidase β

Cells

Plant defence responses to adverse environmental conditions include different stress signalling, ... more Plant defence responses to adverse environmental conditions include different stress signalling, allowing plant acclimation and survival. Among these responses one of the most common, immediate, and effective is the modulation of the stomatal aperture, which integrates different transduction pathways involving hydrogen peroxide (H2O2), calcium (Ca2+), nitric oxide (NO), phytohormones and other signalling components. The Arabidopsis thaliana copper amine oxidases β (AtCuAOβ) encodes an apoplastic CuAO expressed in guard cells and root protoxylem tissues which oxidizes polyamines to aminoaldehydes with the production of H2O2 and ammonia. Here, its role in stomatal closure, signalled by the wound-associated phytohormone methyl-jasmonate (MeJA) was explored by pharmacological and genetic approaches. Obtained data show that AtCuAOβ tissue-specific expression is induced by MeJA, especially in stomata guard cells. Interestingly, two Atcuaoβ T-DNA insertional mutants are unresponsive to thi...

Research paper thumbnail of Microbiological Quality of Ready-To-Eat Salads During Shelf Life and Home Refrigeration

The market of ready-to-eat salads is experiencing a noticeable growth in Europe. Since they are i... more The market of ready-to-eat salads is experiencing a noticeable growth in Europe. Since they are intended to be consumed without additional treatments, these ready-to-eat products are associated with a high microbiological risk. The aim of this work was to evaluate the microbiological quality and safety of ready-to-eat salads sold in widespread supermarket chains in Lazio, Italy, at the packaging date, during shelf-life and during home-refrigeration. The study also aimed to determine the differences between low, medium, and high cost products. Salmonella spp., L. monocytogenes were chosen as safety indicators as specified by European regulations while total aerobic mesophilic bacteria and Escherichia coli were chosen as quality indicators as suggested by national guidelines. Analyses were performed following the ISO standards and in parallel, for the evaluation of total aerobic mesophilic bacteria, with an alternative colorimetric system, the Micro Biological Survey method, in order ...

Research paper thumbnail of Maize polyamine oxidase: antibody development and ultrastuctural localization

Research paper thumbnail of Studies on the Vicia faba diamine oxidase system and its role in the response to Ascochyta fabae and to wounding

Research paper thumbnail of Plant Copper Amine Oxidases: Key Players in Hormone Signaling Leading to Stress-Induced Phenotypic Plasticity

International Journal of Molecular Sciences

Polyamines are ubiquitous, low-molecular-weight aliphatic compounds, present in living organisms ... more Polyamines are ubiquitous, low-molecular-weight aliphatic compounds, present in living organisms and essential for cell growth and differentiation. Copper amine oxidases (CuAOs) oxidize polyamines to aminoaldehydes releasing ammonium and hydrogen peroxide, which participates in the complex network of reactive oxygen species acting as signaling molecules involved in responses to biotic and abiotic stresses. CuAOs have been identified and characterized in different plant species, but the most extensive study on a CuAO gene family has been carried out in Arabidopsis thaliana. Growing attention has been devoted in the last years to the investigation of the CuAO expression pattern during development and in response to an array of stress and stress-related hormones, events in which recent studies have highlighted CuAOs to play a key role by modulation of a multilevel phenotypic plasticity expression. In this review, the attention will be focused on the involvement of different AtCuAOs in ...

Research paper thumbnail of Determination of Copper Amine Oxidase Activity in Plant Tissues

Methods in Molecular Biology

If you can submit your illustrations in an electronic form, please submit the original graphic fi... more If you can submit your illustrations in an electronic form, please submit the original graphic files. Do not insert figures into your Word document. Humana Press prefers that files be submitted in TIFF or EPS format, with at least 300 dpi resolution. PDF, JPG, Excel, and PowerPoint files may also be acceptable. Please check with your editor if you have questions regarding specific figures. Humana Press prefers that art be submitted as electronic files rather than as hard copies; however, scanned images may not be of sufficient quality for reproduction, and authors/editors should expect to submit hard copies of scanned art along with their manuscript. Please scan art at 600 dpi. Remember when considering figures that they will probably be reduced to fit onto a book page, so pay particular attention to making labels highly legible and not too small. You may want to photocopy your figures to the expected final size as a test to determine legibility. The usable page size of the book will usually be about 4.5 x 7.5 inches. Most figures (including their caption) will occupy half a page. Labels should be in a sans-serif font, preferably Helvetica. When at final reduction the size should be no smaller than 8 point. Please ensure that your figures are clearly labeled. Number tables separately.

Research paper thumbnail of Microbiological Quality of Ready-to-Eat Leafy Green Salads during Shelf-Life and Home-Refrigeration

Foods

The market of ready-to-eat leafy green salads is experiencing a noticeable growth in Europe. Sinc... more The market of ready-to-eat leafy green salads is experiencing a noticeable growth in Europe. Since they are intended to be consumed without additional treatments, these ready-to-eat products are associated with a high microbiological risk. The aim of this work was to evaluate the microbiological quality and safety of ready-to-eat leafy green salads sold in widespread supermarket chains in Lazio, Italy, on the packaging date during shelf-life and during home-refrigeration. The study also aimed to determine the differences between low-, medium-, and high-cost products. Salmonella spp. and L. monocytogenes were chosen as safety indicators as specified by European regulations while total aerobic mesophilic bacteria and Escherichia coli were chosen as quality indicators as suggested by national guidelines. Analyses were performed following the ISO standards and in parallel for the evaluation of total aerobic mesophilic bacteria, with an alternative colorimetric system, the Micro Biologic...

Research paper thumbnail of Microbiological Quality of Ready-To-Eat Salads During Shelf Life and Home Refrigeration

The market of ready-to-eat salads is experiencing a noticeable growth in Europe. The commercial s... more The market of ready-to-eat salads is experiencing a noticeable growth in Europe. The commercial success of these products is linked to the growing demand for fresh, healthy and nutritionally valuable products that can be consumed without preparation time and are perceived as safe and very high-quality products. Since they are intended to be consumed without additional treatments, these ready-to-eat products are associated with a high microbiological risk. The aim of this work was to evaluate the microbiological quality and safety of ready-to-eat salads sold in widespread supermarket chains in Lazio, Italy, at the packaging date, during shelf-life and during home-refrigeration. The study also aimed to determine the differences between low, medium and high cost products. Salmonella spp., L. monocytogenes were chosen as safety indicators as specified by European regulations while total aerobic mesophilic bacteria and Escherichia coli were chosen as quality indicators as suggested by na...

Research paper thumbnail of Determination of Copper Amine Oxidase Activity in Plant Tissues

Polyamines, Oct 28, 2017

If you can submit your illustrations in an electronic form, please submit the original graphic fi... more If you can submit your illustrations in an electronic form, please submit the original graphic files. Do not insert figures into your Word document. Humana Press prefers that files be submitted in TIFF or EPS format, with at least 300 dpi resolution. PDF, JPG, Excel, and PowerPoint files may also be acceptable. Please check with your editor if you have questions regarding specific figures. Humana Press prefers that art be submitted as electronic files rather than as hard copies; however, scanned images may not be of sufficient quality for reproduction, and authors/editors should expect to submit hard copies of scanned art along with their manuscript. Please scan art at 600 dpi. Remember when considering figures that they will probably be reduced to fit onto a book page, so pay particular attention to making labels highly legible and not too small. You may want to photocopy your figures to the expected final size as a test to determine legibility. The usable page size of the book will usually be about 4.5 x 7.5 inches. Most figures (including their caption) will occupy half a page. Labels should be in a sans-serif font, preferably Helvetica. When at final reduction the size should be no smaller than 8 point. Please ensure that your figures are clearly labeled. Number tables separately.

Research paper thumbnail of Leaf-Wounding Long-Distance Signaling Targets AtCuAOβ Leading to Root Phenotypic Plasticity

Plants

The Arabidopsis gene AtCuAOβ (At4g14940) encodes an apoplastic copper amine oxidase (CuAO) highly... more The Arabidopsis gene AtCuAOβ (At4g14940) encodes an apoplastic copper amine oxidase (CuAO) highly expressed in guard cells of leaves and flowers and in root vascular tissues, especially in protoxylem and metaxylem precursors, where its expression is strongly induced by the wound signal methyl jasmonate (MeJA). The hydrogen peroxide (H2O2) derived by the AtCuAOβ-driven oxidation of the substrate putrescine (Put), mediates the MeJA–induced early root protoxylem differentiation. Considering that early root protoxylem maturation was also induced by both exogenous Put and leaf wounding through a signaling pathway involving H2O2, in the present study we investigated the role of AtCuAOβ in the leaf wounding-induced early protoxylem differentiation in combination with Put treatment. Quantitative and tissue specific analysis of AtCuAOβ gene expression by RT-qPCR and promoter::green fluorescent protein-β-glucuronidase fusion analysis revealed that wounding of the cotiledonary leaf induced AtC...

Research paper thumbnail of Developmental, hormone- and stress-modulated expression profiles of four members of the Arabidopsis copper-amine oxidase gene family

Plant Physiology and Biochemistry

Copper-containing amine oxidases (CuAOs) catalyze polyamines (PAs) terminal oxidation producing a... more Copper-containing amine oxidases (CuAOs) catalyze polyamines (PAs) terminal oxidation producing ammonium, an aminoaldehyde and hydrogen peroxide (H2O2). Plant CuAOs are induced by stress-related hormones, methyl-jasmonate (MeJA), abscisic acid (ABA) and salicylic acid (SA). In the Arabidopsis genome, eight genes encoding CuAOs have been identified. Here, a comprehensive investigation of the expression pattern of four genes encoding AtCuAOs from the α and γ phylogenetic subfamilies, the two peroxisomal AtCuAOα2 (At1g31690) and AtCuAOα3 (At1g31710) and the two apoplastic AtCuAOγ1 (At1g62810) and AtCuAOγ2 (At3g43670), has been carried out by RT-qPCR and promoter::green fluorescent protein-β-glucuronidase fusion (GFP-GUS). Expression in hydathodes of new emerging leaves (AtCuAOγ1 and AtCuAOγ2) and/or cotyledons (AtCuAOα2, AtCuAOγ1 and AtCuAOγ2) as well as in vascular tissues of new emerging leaves and in cortical root cells at the division/elongation transition zone (AtCuAOγ1), columella cells (AtCuAOγ2) or hypocotyl and root (AtCuAOα3) was identified. Quantitative and tissue-specific gene expression analysis performed by RT-qPCR and GUS-staining in 5- and 7-day-old seedlings under stress conditions or after treatments with hormones or PAs, revealed that all four AtCuAOs were induced during dehydration recovery, wounding, treatment with indoleacetic acid (IAA) and putrescine (Put). AtCuAOα2, AtCuAOα3, AtCuAOγ1 and AtCuAOγ2 expression in vascular tissues and hydathodes involved in water supply and/or loss, along with a dehydration-recovery dependent gene expression, would suggest a role in water balance homeostasis. Moreover, occurrence in zones where an auxin maximum has been observed along with an IAA-induced alteration of expression profiles, support a role in tissue maturation and xylem differentiation events.

Research paper thumbnail of The Copper Amine Oxidase AtCuAOδ Participates in Abscisic Acid-Induced Stomatal Closure in Arabidopsis

Plants

Plant copper amine oxidases (CuAOs) are involved in wound healing, defense against pathogens, met... more Plant copper amine oxidases (CuAOs) are involved in wound healing, defense against pathogens, methyl-jasmonate-induced protoxylem differentiation, and abscisic acid (ABA)-induced stomatal closure. In the present study, we investigated the role of the Arabidopsis thaliana CuAOδ (AtCuAOδ; At4g12290) in the ABA-mediated stomatal closure by genetic and pharmacological approaches. Obtained data show that AtCuAOδ is up-regulated by ABA and that two Atcuaoδ T-DNA insertional mutants are less responsive to this hormone, showing reduced ABA-mediated stomatal closure and H2O2 accumulation in guard cells as compared to the wild-type (WT) plants. Furthermore, CuAO inhibitors, as well as the hydrogen peroxide (H2O2) scavenger N,N1-dimethylthiourea, reversed most of the ABA-induced stomatal closure in WT plants. Consistently, AtCuAOδ over-expressing transgenic plants display a constitutively increased stomatal closure and increased H2O2 production compared to WT plants. Our data suggest that AtCu...

Research paper thumbnail of Stress-Triggered Long-Distance Communication Leads to Phenotypic Plasticity: The Case of the Early Root Protoxylem Maturation Induced by Leaf Wounding in Arabidopsis

Plants

Root architecture and xylem phenotypic plasticity influence crop productivity by affecting water ... more Root architecture and xylem phenotypic plasticity influence crop productivity by affecting water and nutrient uptake, especially under those environmental stress, which limit water supply or imply excessive water losses. Xylem maturation depends on coordinated events of cell wall lignification and developmental programmed cell death (PCD), which could both be triggered by developmental- and/or stress-driven hydrogen peroxide (H2O2) production. Here, the effect of wounding of the cotyledonary leaf on root protoxylem maturation was explored in Arabidopsis thaliana by analysis under Laser Scanning Confocal Microscope (LSCM). Leaf wounding induced early root protoxylem maturation within 3 days from the injury, as after this time protoxylem position was found closer to the tip. The effect of leaf wounding on protoxylem maturation was independent from root growth or meristem size, that did not change after wounding. A strong H2O2 accumulation was detected in root protoxylem 6 h after leaf...

Research paper thumbnail of Editorial: Molecular Mechanisms Underlying Polyamine Functions in Plants

Frontiers in Plant Science, 2017

Research paper thumbnail of Copper-Containing Amine Oxidases and FAD-Dependent Polyamine Oxidases Are Key Players in Plant Tissue Differentiation and Organ Development

Frontiers in Plant Science, 2016

Plant polyamines are catabolized by two classes of amine oxidases, the copper amine oxidases (CuA... more Plant polyamines are catabolized by two classes of amine oxidases, the copper amine oxidases (CuAOs) and the flavin adenine dinucleotide (FAD)-dependent polyamine oxidases (PAOs). These enzymes differ to each other in substrate specificity, catalytic mechanism and subcellular localization. CuAOs and PAOs contribute to several physiological processes both through the control of polyamine homeostasis and as sources of biologically-active reaction products. CuAOs and PAOs have been found at high level in the cell-wall of several species belonging to Fabaceae and Poaceae families, respectively, especially in tissues fated to undertake extensive wall loosening/stiffening events and/or in cells undergoing programmed cell death (PCD). Apoplastic CuAOs and PAOs have been shown to play a key role as a source of H 2 O 2 in light-or developmentally-regulated differentiation events, thus influencing cell-wall architecture and maturation as well as PCD. Moreover, growing evidence suggests a key role of intracellular CuAOs and PAOs in several facets of plant development. Here, we discuss recent advances in understanding the contribution of different CuAOs/PAOs, as well as their cross-talk with different intracellular and apoplastic metabolic pathways, in tissue differentiation and organ development.

Research paper thumbnail of Cytotoxic effect induced by maize polyamine oxidase in presence of spermine in human cancer cells

Research paper thumbnail of Comparative analysis of the role of the different Arabidopsis polyamine oxidases in plant defense responses to environmental stresses

Research paper thumbnail of Polyamine Catabolism in Arabidopsis Thaliana

Research paper thumbnail of The apoplastic copper amine oxidase AtCuAOβ plays a role in stomatal closure induced by wounding, jasmonate or Microbe Associated Molecular Patterns (MAMPS)

Research paper thumbnail of Arabidopsis N-acetyltransferase activity 2 preferentially acetylates 1,3-diaminopropane and thialysine

Plant Physiology and Biochemistry

Research paper thumbnail of A New Player in Jasmonate-Mediated Stomatal Closure: The Arabidopsis thaliana Copper Amine Oxidase β

Cells

Plant defence responses to adverse environmental conditions include different stress signalling, ... more Plant defence responses to adverse environmental conditions include different stress signalling, allowing plant acclimation and survival. Among these responses one of the most common, immediate, and effective is the modulation of the stomatal aperture, which integrates different transduction pathways involving hydrogen peroxide (H2O2), calcium (Ca2+), nitric oxide (NO), phytohormones and other signalling components. The Arabidopsis thaliana copper amine oxidases β (AtCuAOβ) encodes an apoplastic CuAO expressed in guard cells and root protoxylem tissues which oxidizes polyamines to aminoaldehydes with the production of H2O2 and ammonia. Here, its role in stomatal closure, signalled by the wound-associated phytohormone methyl-jasmonate (MeJA) was explored by pharmacological and genetic approaches. Obtained data show that AtCuAOβ tissue-specific expression is induced by MeJA, especially in stomata guard cells. Interestingly, two Atcuaoβ T-DNA insertional mutants are unresponsive to thi...

Research paper thumbnail of Microbiological Quality of Ready-To-Eat Salads During Shelf Life and Home Refrigeration

The market of ready-to-eat salads is experiencing a noticeable growth in Europe. Since they are i... more The market of ready-to-eat salads is experiencing a noticeable growth in Europe. Since they are intended to be consumed without additional treatments, these ready-to-eat products are associated with a high microbiological risk. The aim of this work was to evaluate the microbiological quality and safety of ready-to-eat salads sold in widespread supermarket chains in Lazio, Italy, at the packaging date, during shelf-life and during home-refrigeration. The study also aimed to determine the differences between low, medium, and high cost products. Salmonella spp., L. monocytogenes were chosen as safety indicators as specified by European regulations while total aerobic mesophilic bacteria and Escherichia coli were chosen as quality indicators as suggested by national guidelines. Analyses were performed following the ISO standards and in parallel, for the evaluation of total aerobic mesophilic bacteria, with an alternative colorimetric system, the Micro Biological Survey method, in order ...

Research paper thumbnail of Maize polyamine oxidase: antibody development and ultrastuctural localization

Research paper thumbnail of Studies on the Vicia faba diamine oxidase system and its role in the response to Ascochyta fabae and to wounding

Research paper thumbnail of Plant Copper Amine Oxidases: Key Players in Hormone Signaling Leading to Stress-Induced Phenotypic Plasticity

International Journal of Molecular Sciences

Polyamines are ubiquitous, low-molecular-weight aliphatic compounds, present in living organisms ... more Polyamines are ubiquitous, low-molecular-weight aliphatic compounds, present in living organisms and essential for cell growth and differentiation. Copper amine oxidases (CuAOs) oxidize polyamines to aminoaldehydes releasing ammonium and hydrogen peroxide, which participates in the complex network of reactive oxygen species acting as signaling molecules involved in responses to biotic and abiotic stresses. CuAOs have been identified and characterized in different plant species, but the most extensive study on a CuAO gene family has been carried out in Arabidopsis thaliana. Growing attention has been devoted in the last years to the investigation of the CuAO expression pattern during development and in response to an array of stress and stress-related hormones, events in which recent studies have highlighted CuAOs to play a key role by modulation of a multilevel phenotypic plasticity expression. In this review, the attention will be focused on the involvement of different AtCuAOs in ...

Research paper thumbnail of Determination of Copper Amine Oxidase Activity in Plant Tissues

Methods in Molecular Biology

If you can submit your illustrations in an electronic form, please submit the original graphic fi... more If you can submit your illustrations in an electronic form, please submit the original graphic files. Do not insert figures into your Word document. Humana Press prefers that files be submitted in TIFF or EPS format, with at least 300 dpi resolution. PDF, JPG, Excel, and PowerPoint files may also be acceptable. Please check with your editor if you have questions regarding specific figures. Humana Press prefers that art be submitted as electronic files rather than as hard copies; however, scanned images may not be of sufficient quality for reproduction, and authors/editors should expect to submit hard copies of scanned art along with their manuscript. Please scan art at 600 dpi. Remember when considering figures that they will probably be reduced to fit onto a book page, so pay particular attention to making labels highly legible and not too small. You may want to photocopy your figures to the expected final size as a test to determine legibility. The usable page size of the book will usually be about 4.5 x 7.5 inches. Most figures (including their caption) will occupy half a page. Labels should be in a sans-serif font, preferably Helvetica. When at final reduction the size should be no smaller than 8 point. Please ensure that your figures are clearly labeled. Number tables separately.

Research paper thumbnail of Microbiological Quality of Ready-to-Eat Leafy Green Salads during Shelf-Life and Home-Refrigeration

Foods

The market of ready-to-eat leafy green salads is experiencing a noticeable growth in Europe. Sinc... more The market of ready-to-eat leafy green salads is experiencing a noticeable growth in Europe. Since they are intended to be consumed without additional treatments, these ready-to-eat products are associated with a high microbiological risk. The aim of this work was to evaluate the microbiological quality and safety of ready-to-eat leafy green salads sold in widespread supermarket chains in Lazio, Italy, on the packaging date during shelf-life and during home-refrigeration. The study also aimed to determine the differences between low-, medium-, and high-cost products. Salmonella spp. and L. monocytogenes were chosen as safety indicators as specified by European regulations while total aerobic mesophilic bacteria and Escherichia coli were chosen as quality indicators as suggested by national guidelines. Analyses were performed following the ISO standards and in parallel for the evaluation of total aerobic mesophilic bacteria, with an alternative colorimetric system, the Micro Biologic...

Research paper thumbnail of Microbiological Quality of Ready-To-Eat Salads During Shelf Life and Home Refrigeration

The market of ready-to-eat salads is experiencing a noticeable growth in Europe. The commercial s... more The market of ready-to-eat salads is experiencing a noticeable growth in Europe. The commercial success of these products is linked to the growing demand for fresh, healthy and nutritionally valuable products that can be consumed without preparation time and are perceived as safe and very high-quality products. Since they are intended to be consumed without additional treatments, these ready-to-eat products are associated with a high microbiological risk. The aim of this work was to evaluate the microbiological quality and safety of ready-to-eat salads sold in widespread supermarket chains in Lazio, Italy, at the packaging date, during shelf-life and during home-refrigeration. The study also aimed to determine the differences between low, medium and high cost products. Salmonella spp., L. monocytogenes were chosen as safety indicators as specified by European regulations while total aerobic mesophilic bacteria and Escherichia coli were chosen as quality indicators as suggested by na...

Research paper thumbnail of Determination of Copper Amine Oxidase Activity in Plant Tissues

Polyamines, Oct 28, 2017

If you can submit your illustrations in an electronic form, please submit the original graphic fi... more If you can submit your illustrations in an electronic form, please submit the original graphic files. Do not insert figures into your Word document. Humana Press prefers that files be submitted in TIFF or EPS format, with at least 300 dpi resolution. PDF, JPG, Excel, and PowerPoint files may also be acceptable. Please check with your editor if you have questions regarding specific figures. Humana Press prefers that art be submitted as electronic files rather than as hard copies; however, scanned images may not be of sufficient quality for reproduction, and authors/editors should expect to submit hard copies of scanned art along with their manuscript. Please scan art at 600 dpi. Remember when considering figures that they will probably be reduced to fit onto a book page, so pay particular attention to making labels highly legible and not too small. You may want to photocopy your figures to the expected final size as a test to determine legibility. The usable page size of the book will usually be about 4.5 x 7.5 inches. Most figures (including their caption) will occupy half a page. Labels should be in a sans-serif font, preferably Helvetica. When at final reduction the size should be no smaller than 8 point. Please ensure that your figures are clearly labeled. Number tables separately.

Research paper thumbnail of Leaf-Wounding Long-Distance Signaling Targets AtCuAOβ Leading to Root Phenotypic Plasticity

Plants

The Arabidopsis gene AtCuAOβ (At4g14940) encodes an apoplastic copper amine oxidase (CuAO) highly... more The Arabidopsis gene AtCuAOβ (At4g14940) encodes an apoplastic copper amine oxidase (CuAO) highly expressed in guard cells of leaves and flowers and in root vascular tissues, especially in protoxylem and metaxylem precursors, where its expression is strongly induced by the wound signal methyl jasmonate (MeJA). The hydrogen peroxide (H2O2) derived by the AtCuAOβ-driven oxidation of the substrate putrescine (Put), mediates the MeJA–induced early root protoxylem differentiation. Considering that early root protoxylem maturation was also induced by both exogenous Put and leaf wounding through a signaling pathway involving H2O2, in the present study we investigated the role of AtCuAOβ in the leaf wounding-induced early protoxylem differentiation in combination with Put treatment. Quantitative and tissue specific analysis of AtCuAOβ gene expression by RT-qPCR and promoter::green fluorescent protein-β-glucuronidase fusion analysis revealed that wounding of the cotiledonary leaf induced AtC...

Research paper thumbnail of Developmental, hormone- and stress-modulated expression profiles of four members of the Arabidopsis copper-amine oxidase gene family

Plant Physiology and Biochemistry

Copper-containing amine oxidases (CuAOs) catalyze polyamines (PAs) terminal oxidation producing a... more Copper-containing amine oxidases (CuAOs) catalyze polyamines (PAs) terminal oxidation producing ammonium, an aminoaldehyde and hydrogen peroxide (H2O2). Plant CuAOs are induced by stress-related hormones, methyl-jasmonate (MeJA), abscisic acid (ABA) and salicylic acid (SA). In the Arabidopsis genome, eight genes encoding CuAOs have been identified. Here, a comprehensive investigation of the expression pattern of four genes encoding AtCuAOs from the α and γ phylogenetic subfamilies, the two peroxisomal AtCuAOα2 (At1g31690) and AtCuAOα3 (At1g31710) and the two apoplastic AtCuAOγ1 (At1g62810) and AtCuAOγ2 (At3g43670), has been carried out by RT-qPCR and promoter::green fluorescent protein-β-glucuronidase fusion (GFP-GUS). Expression in hydathodes of new emerging leaves (AtCuAOγ1 and AtCuAOγ2) and/or cotyledons (AtCuAOα2, AtCuAOγ1 and AtCuAOγ2) as well as in vascular tissues of new emerging leaves and in cortical root cells at the division/elongation transition zone (AtCuAOγ1), columella cells (AtCuAOγ2) or hypocotyl and root (AtCuAOα3) was identified. Quantitative and tissue-specific gene expression analysis performed by RT-qPCR and GUS-staining in 5- and 7-day-old seedlings under stress conditions or after treatments with hormones or PAs, revealed that all four AtCuAOs were induced during dehydration recovery, wounding, treatment with indoleacetic acid (IAA) and putrescine (Put). AtCuAOα2, AtCuAOα3, AtCuAOγ1 and AtCuAOγ2 expression in vascular tissues and hydathodes involved in water supply and/or loss, along with a dehydration-recovery dependent gene expression, would suggest a role in water balance homeostasis. Moreover, occurrence in zones where an auxin maximum has been observed along with an IAA-induced alteration of expression profiles, support a role in tissue maturation and xylem differentiation events.

Research paper thumbnail of The Copper Amine Oxidase AtCuAOδ Participates in Abscisic Acid-Induced Stomatal Closure in Arabidopsis

Plants

Plant copper amine oxidases (CuAOs) are involved in wound healing, defense against pathogens, met... more Plant copper amine oxidases (CuAOs) are involved in wound healing, defense against pathogens, methyl-jasmonate-induced protoxylem differentiation, and abscisic acid (ABA)-induced stomatal closure. In the present study, we investigated the role of the Arabidopsis thaliana CuAOδ (AtCuAOδ; At4g12290) in the ABA-mediated stomatal closure by genetic and pharmacological approaches. Obtained data show that AtCuAOδ is up-regulated by ABA and that two Atcuaoδ T-DNA insertional mutants are less responsive to this hormone, showing reduced ABA-mediated stomatal closure and H2O2 accumulation in guard cells as compared to the wild-type (WT) plants. Furthermore, CuAO inhibitors, as well as the hydrogen peroxide (H2O2) scavenger N,N1-dimethylthiourea, reversed most of the ABA-induced stomatal closure in WT plants. Consistently, AtCuAOδ over-expressing transgenic plants display a constitutively increased stomatal closure and increased H2O2 production compared to WT plants. Our data suggest that AtCu...

Research paper thumbnail of Stress-Triggered Long-Distance Communication Leads to Phenotypic Plasticity: The Case of the Early Root Protoxylem Maturation Induced by Leaf Wounding in Arabidopsis

Plants

Root architecture and xylem phenotypic plasticity influence crop productivity by affecting water ... more Root architecture and xylem phenotypic plasticity influence crop productivity by affecting water and nutrient uptake, especially under those environmental stress, which limit water supply or imply excessive water losses. Xylem maturation depends on coordinated events of cell wall lignification and developmental programmed cell death (PCD), which could both be triggered by developmental- and/or stress-driven hydrogen peroxide (H2O2) production. Here, the effect of wounding of the cotyledonary leaf on root protoxylem maturation was explored in Arabidopsis thaliana by analysis under Laser Scanning Confocal Microscope (LSCM). Leaf wounding induced early root protoxylem maturation within 3 days from the injury, as after this time protoxylem position was found closer to the tip. The effect of leaf wounding on protoxylem maturation was independent from root growth or meristem size, that did not change after wounding. A strong H2O2 accumulation was detected in root protoxylem 6 h after leaf...

Research paper thumbnail of Editorial: Molecular Mechanisms Underlying Polyamine Functions in Plants

Frontiers in Plant Science, 2017

Research paper thumbnail of Copper-Containing Amine Oxidases and FAD-Dependent Polyamine Oxidases Are Key Players in Plant Tissue Differentiation and Organ Development

Frontiers in Plant Science, 2016

Plant polyamines are catabolized by two classes of amine oxidases, the copper amine oxidases (CuA... more Plant polyamines are catabolized by two classes of amine oxidases, the copper amine oxidases (CuAOs) and the flavin adenine dinucleotide (FAD)-dependent polyamine oxidases (PAOs). These enzymes differ to each other in substrate specificity, catalytic mechanism and subcellular localization. CuAOs and PAOs contribute to several physiological processes both through the control of polyamine homeostasis and as sources of biologically-active reaction products. CuAOs and PAOs have been found at high level in the cell-wall of several species belonging to Fabaceae and Poaceae families, respectively, especially in tissues fated to undertake extensive wall loosening/stiffening events and/or in cells undergoing programmed cell death (PCD). Apoplastic CuAOs and PAOs have been shown to play a key role as a source of H 2 O 2 in light-or developmentally-regulated differentiation events, thus influencing cell-wall architecture and maturation as well as PCD. Moreover, growing evidence suggests a key role of intracellular CuAOs and PAOs in several facets of plant development. Here, we discuss recent advances in understanding the contribution of different CuAOs/PAOs, as well as their cross-talk with different intracellular and apoplastic metabolic pathways, in tissue differentiation and organ development.