Jasmonic acid methyl ester induces the synthesis of a cytoplasmic/nuclear chito-oligosaccharide binding lectin in tobacco leaves.

In contrast to animal lectins, no evidence has indicated the occurrence of plant lectins, which recognize and bind "endogenous" receptors and accordingly are involved in recognition mechanisms within the organism itself. Here we show that the plant hormone jasmonic acid methyl ester (JAME) induces in leaves of Nicotiana tabacum (var. Samsun NN) the expression of a lectin that is absent from untreated plants.

Immunolocalization of 1- O-sinapoylglucose:malate sinapoyltransferase in Arabidopsis thaliana.

The serine carboxypeptidase-like protein 1- O-sinapoylglucose:malate sinapoyltransferase (SMT) catalyzes the transfer of the sinapoyl moiety of 1- O-sinapoylglucose to malate in the formation of sinapoylmalate in some members of the Brassicaceae. Rabbit polyclonal monospecific antibodies were raised against the recombinant SMT produced in Escherichia coli from the corresponding Arabidopsis thaliana (L.) Heynh.

Occurrence and localization of apocarotenoids in arbuscular mycorrhizal plant roots.

The core structure of the yellow pigment from arbuscular mycorrhizal (AM) maize roots contains the apocarotenoids mycorradicin (an acyclic C14 polyene) and blumenol C cellobioside (a C13 cyclohexenone diglucoside). The pigment seems to be a mixture of different esterification products of these apocarotenoids. It is insoluble in water and accumulates as hydrophobic droplets in the vacuoles of root cortical cells.

Purification, characterization, immunolocalization and structural analysis of the abundant cytoplasmic beta-amylase from Calystegia sepium (hedge bindweed) rhizomes.

An abundant catalytically active beta-amylase (EC 3.2.1.

Reorganization of tobacco root plastids during arbuscule development.

In the present paper we analyzed plastid populations labeled by the green fluorescent protein in non-mycorrhizal and mycorrhizal roots of tobacco (Nicotiana tahacum L.). We show by confocal laser scanning microscopy (i) a dramatic increase in these plastids in mycorrhizal roots and (ii) the formation of dense plastid networks covering the symbiotic interface of the arbuscular mycorrhiza, the arbuscule.

Tomato ribonuclease LX with the functional endoplasmic reticulum retention motif HDEF is expressed during programmed cell death processes, including xylem differentiation, germination, and senescence.

We have studied the subcellular localization of the acid S-like ribonuclease (RNase) LX in tomato (Lycopersicon esculentum Mill.) cells using a combination of biochemical and immunological methods. It was found that the enzyme, unexpectedly excluded from highly purified vacuoles, accumulates in the endoplasmic reticulum.

Iris bulbs express type 1 and type 2 ribosome-inactivating proteins with unusual properties.

Two closely related lectins from bulbs of the Dutch iris (Iris hollandica var. Professor Blaauw) have been isolated and cloned. Both lectins, called Iris agglutinin b and Iris agglutinin r, possess N-glycosidase activity and share a high sequence similarity with previously described type 2 ribosome-inactivating proteins (RIP).

Tissue-specific oxylipin signature of tomato flowers: allene oxide cyclase is highly expressed in distinct flower organs and vascular bundles.

A crucial step in the biosynthesis of jasmonic acid (JA) is the formation of its correct stereoisomeric precursor, cis(+)12-oxophytodienoic acid (OPDA). This step is catalysed by allene oxide cyclase (AOC), which has been recently cloned from tomato. In stems, young leaves and young flowers, AOC mRNA accumulates to a low level, contrasting with a high accumulation in flower buds, flower stalks and roots.

The galactose-binding and mannose-binding jacalin-related lectins are located in different sub-cellular compartments.

A galactose-specific and a mannose-specific lectin of the family of the jacalin-related lectins have been localized by immunofluorescence microscopy. The present localization studies provide for the first time unambiguous evidence for the cytoplasmic location of the mannose-specific jacalin-related lectin from rhizomes of Calystegia sepium, which definitely differs from the vacuolar location of the galactose-specific jacalin from Artocarpus integrifolia. These observations support the hypothesis that the galactose-specific jacalin-related lectins evolved from their mannose-specific homologues through the acquisition of vacuolar targeting sequences.

Expression of cucumber lipid-body lipoxygenase in transgenic tobacco: lipid-body lipoxygenase is correctly targeted to seed lipid bodies.

A particular isoform of lipoxygenase (LOX, EC 1.13.11.

Molecular cloning of allene oxide cyclase. The enzyme establishing the stereochemistry of octadecanoids and jasmonates.

Allene oxide cyclase (EC ) catalyzes the stereospecific cyclization of an unstable allene oxide to (9S,13S)-12-oxo-(10,15Z)-phytodienoic acid, the ultimate precursor of jasmonic acid. This dimeric enzyme has previously been purified, and two almost identical N-terminal peptides were found, suggesting allene oxide cyclase to be a homodimeric protein. Furthermore, the native protein was N-terminally processed.

Allene oxide synthases of barley (Hordeum vulgare cv. Salome): tissue specific regulation in seedling development.

Allene oxide synthase (AOS) is the first enzyme in the lipoxygenase (LOX) pathway which leads to formation of jasmonic acid (JA). Two full-length cDNAs of AOS designated as AOS1 and AOS2, respectively, were isolated from barley (H. vulgare cv.

Nuclear gamma-tubulin during acentriolar plant mitosis.

Neither the molecular mechanism by which plant microtubules nucleate in the cytoplasm nor the organization of plant mitotic spindles, which lack centrosomes, is well understood. Here, using immunolocalization and cell fractionation techniques, we provide evidence that gamma-tubulin, a universal component of microtubule organizing centers, is present in both the cytoplasm and the nucleus of plant cells. The amount of gamma-tubulin in nuclei increased during the G(2) phase, when cells are synchronized or sorted for particular phases of the cell cycle.

Cloning and expression of a new cDNA from monocotyledonous plants coding for a diadenosine 5',5'''-P1,P4-tetraphosphate hydrolase from barley (Hordeum vulgare).

From a cDNA library generated from mRNA of white leaf tissues of the ribosome-deficient mutant 'albostrians' of barley (Hordeum vulgare cv. Haisa) a cDNA was isolated carrying 54.2% identity to a recently published cDNA which codes for the diadenosine-5',5'''-P1,P4-tetraphosphate (Ap4A) hydrolase of Lupinus angustifolius (Maksel et al.

Amino acid conjugates of jasmonic acid induce jasmonate-responsive gene expression in barley (Hordeum vulgare L.) leaves.

Leaves of barley (Hordeum vulgare L. cv. Salome) treated with jasmonic acid (JA), its methyl ester (JM), or its amino acid conjugates exhibit up-regulation of specific genes and down-regulation of house-keeping genes.

Methyl jasmonate induces an O-methyltransferase in barley.

We have previously described a truncated cDNA clone for a barley (Hordeum vulgare L. cv. Salome) jasmonate regulated gene, JRG5, which shows homology to caffeic acid O-methyltransferase (COMT).

Expression of the ribosome-inactivating protein JIP60 from barely in transgenic tobacco leads to an abnormal phenotype and alterations on the level of translation.

In this paper we report the in-planta activity of the ribosome-inactivating protein JIP60, a 60-kDa jasmonate-induced protein from barley (Hordeum vulgare L.), in transgenic tobacco (Nicotiana tabacum L.) plants.

Developmental and tissue-specific expression of JIP-23, a jasmonate-inducible protein of barley.

Developmental expression of a 23 kDa jasmonate-induced protein (JIP-23) of barley leaves (Hordeum vulgare cv. Salome) was studied by measuring the time-dependent accumulation of transcript and protein during germination. Tissue-specific expression of JIP-23 was analyzed immunocytochemically and by in situ hybridizations, respectively.

Nuclear DNA synthesis during the induction of embryogenesis in cultured microspores and pollen of Brassica napus L.

The dynamics of nuclear DNA synthesis were analysed in isolated microspores and pollen of Brassica napus that were induced to form embryos. DNA synthesis was visualized by the immunocytochemical labelling of incorporated Bromodeoxyuridine (BrdU), applied continuously or as a pulse during the first 24 h of culture under embryogenic (32 °C) and non-embryogenic (18 °C) conditions. Total DNA content of the nuclei was determined by microspectrophotometry.

Compartmentation of uridine 5'-triphosphate occurs during synthesis of cytoplasmic and mitochondrial ribosomal RNAs of cultured tomato cells but not during synthesis of cytoplasmic ribosomal and transfer RNAs.

Compartmentation of uridine 5'-triphosphate (UTP) was studied during the nucleolar synthesis of cytoplasmic ribosomal RNA (cyt-rRNA) and the synthesis of cytoplasmic transfer RNA (cyt-tRNA) in the nuclear matrix as well as the synthesis of mitochondrial ribosomal RNA (mt-rRNA) in tomato (Lycopersicon esculentum Mill. cv. Lukullus) cell-suspension culture using the approach of Wiegers et al.