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1.
Tomato (Lycopersicon esculentum Mill. cv. Moneymaker) plants have been wounded to induce the accumulation of proteinase-inhibitor proteins (PI proteins) at the local site of injury and systemically in unwounded tissues. To determine the range of genes affected in the wound-response, polysomal mRNA has been isolated from the damaged leaves and from systemically responding leaves over a time-course of 2, 4, 10 and 24 h after wounding. Changes in the pattern of 35S-translation products indicate that the events that occur at the local wound-site are different from those that occur systemically, both with respect to the number of genes that are regulated and the timing of their regulation. In order to compare the effects of wounding and an endogenous systemic signal generated at the wound-site with those of elicitor (proteinase-inhibitor-inducing factor, PIIF) treatment of excised plants, polysomal mRNA has also been isolated from leaves of plants over a time-course of 2, 4, 10 and 24 h after PIIF-treatment. Changes in the pattern of 35S-translation products indicates that the events induced by PIIF resemble those induced by mechanical injury, rather than those induced by the endogenous systemic signal.Abbreviations IFF
isoelectric focussing
- PI proteins
proteinase inhibitor proteins
- PIIF
proteinase-inhibitor-inducing factor
- ssRubisco
small subunit of ribulose-1,5-bisphosphate carboxylase 相似文献
2.
Dr. Frederick Grinnell Akira Takashima Cheryl Lamke-Seymour 《Cell and tissue research》1986,246(1):13-21
Summary Human foreskin fibroblasts were used to reorganize hydrated collagen gels into a dermal-like matrix, after which freshly isolated keratinocytes isolated from rabbit ear skin were placed on the surfaces of the matrices and cultured for up to 12 days. Transmission electron microscopy revealed 8–12 cell layers of epidermal cells organized in three distinct strata. The basal stratum consisted of cuboidal to columnar cells with typical complement of organelles, oval nuclei, and prominent tonofilaments inserting into desmosomes. Mitotic cells often were found at this level. There was no well-defined basement membrane region; rather, many of the cells appeared to be in close contact with collagen fibrils. The intermediate stratum of suprabasal cells consisted of elongated cells that had reduced organelles, but still were connected to each other by desmosomes. Finally, the superficial stratum of suprabasal cells contained cells that were completely flattened and often appeared to be sloughing off the apical surfaces of the cultures. Indirect immunofluorescence studies carried out on frozen sections revealed bullous pemphigoid antigen associated with basal epidermal cells; pemphigus vulgaris antigen around the epidermal cells of all strata, and keratin present in the epidermal cells of all strata. Filaggrin was observed in punctate and fibrillar arrangements in suprabasal cells. Fibronectin was found in a linear deposit at the dermal-epidermal junction and around the fibroblasts in the reorganized collagen gels. Type-IV collagen and laminin, however, were not detected. 相似文献
3.
4.
Anne Marpeau Jocelyne Walter Jacqueline Launay Jacqueline Charon Philippe Baradat Michel Gleizes 《Trees - Structure and Function》1989,3(4):220-226
Summary The effect of wounds on the volatile terpene composition of the living bark of Pinus pinaster Ait. (maritime pine) twigs was investigated with respect to the processes of mono- and sesquiterpene hydrocarbon biosynthesis. The large increase in the amounts of - and -pinene is a characteristic feature after a mechanical injury, whereas the quantities of the other terpenes are only slightly increased. This is due to the reactivation of the resin duct secretory cells of primary origin located in cortical tissues. The effect of wounding is observed over a long period and the terpene profiles are very different at the end of the experiments as compared with the initial profiles of the same tissues. The traumatic essential oil (obtained after mechanical traumatism) resembles an oleoresin extracted from tissues of secondary origin. Statistical analysis underlines the effects of the between-tree variations and of the dates of application of the wound. 相似文献
5.
Gap junction-mediated intercellular communication was analyzed in a model system in which tissue necrosis and remodeling could be modulated. This in vitro system, previously used for analysis of epithelial-mesenchymal tissue interaction, was modified to permit analysis of the presence and extent of intercellular communition by monitoring intercellular transfer of the micro-injected fluorescent dye, Lucifer Yellow. Light and transmission electronmicroscopy were employed to correlate the presence and degree of gap junctional communication (coupling) with tissue morphology. Digital image analysis was used to determine cell density and mitotic indices within the outgrowths of explants. Our results indicated that cell communication in outgrowths adjacent to necrotic foci within an explant was minimal or absent. Cell-coupling in outgrowths adjacent to a compartment of viable mesenchyme was significantly higher-equivalent to unseparated control cultures. A time-course study demonstrated correlation of increased levels of cell-coupling in outgrowths with the level of tissue remodeling within an explant. Our conclusions from these studies are that embryonic mesenchymal cell populations may be selectively uncoupled as a result of alterations in the microenvironment produced by a proximate impaired cell population. It is proposed that endogenous factors in the microenvironment (wound signals), emanating from impaired cell populations, regulate gap junction-mediated intercellular communication in adjacent viable tissue. Normal, unimpaired populations of cells surrounding an area of injury are thereby isolated from the effects of a potentially toxic environment. This could serve as a protective function in development and may represent, in a more general sense, part of the repertoire of events associated with tissue repair and remodeling. 相似文献
6.
Light-and electron-microscopic autoradiography have been used to study fibroblast transformation into endothelial cells in the formation of new blood vessels during wound healing in rabbit ear chambers. When cultured fibroblasts labeled with tritium thymidine were transplanted autologously into the chambers, newly formed blood vessels contained endothelial cells labeled with tritium thymidine. This result suggests that fibroblasts play a pivotal role in angiogenesis, as progenitors of endothelial cells in newly formed blood vessels. 相似文献
7.
The main barriers to the movement of water and ions in young roots of Zea mays were located by observing the effects of wounding various cell layers of the cortex on the roots' hydraulic conductivities and root pressures. These parameters were measured with a root pressure probe. Injury to the epidermis and cortex caused no significant change in hydraulic conductivity and either no change or a slight decline in root pressure. Injury to a small area of the endodermis did not change the hydraulic conductivity but caused an immediate and substantial drop in root pressure. When large areas of epidermis and cortex were removed (15–38% of total root mass), the endodermis was always injured and root pressure fell. The hydraulic conductance of the root increased but only by a factor of 1.2–2.7. The results indicate that the endodermis is the main barrier to the radial movement of ions but not water. The major barrier to water is the membranes and apoplast of all the living tissue. These conclusions were drawn from experiments in which hydrostatic-pressure differences were used to induce water flows across young maize roots which had an immature exodermis and an endodermis with Casparian bands but no suberin lamellae or secondary walls. The different reactions of water and ions to the endodermis can be explained by the huge difference in the permeability of membranes to these substances. A hydrophobic wall barrier such as the Casparian band should have little effect on the movement of water, which permeates membranes and, perhaps, also the Casparian bands easily. However, hydrophobic wall depositions largely prevent the movement of ions. Several hours after wounding the endodermis, root pressure recovered to some extent in most of the experiments, indicating that the wound in the endodermis had been partially healed.Abbreviations Lpr
hydraulic conductivity of root; T1/2 = half-time of water exchange between root xylem and external medium
This research was supported by a grant from EUROSILVA (project no. 39473C) to E.S., and by a Bilateral Exchange Grant jointly funded by the Deutsche Forschungsgemeinschaft and the Natural Sciences and Engineering Research Council of Canada to C.A.P. We thank Mr. Burkhard Stumpf for his excellent technicial assistance. 相似文献
8.
Summary Taurine which has antioxidant effects is also known to have effects on cell proliferation, inflammation and collagenogenesis. The aim of this study was to investigate the effect of taurine on incisional skin wounds.The mice incised on the dorsal area were divided into control and experimental groups. Saline was injected intraperitoneally to half of the animals in the control group and locally applied to the other half. Fifty mM taurine solution was given intraperitoneally to the first half of the experimental animals and locally to the second half of the experimental group.After four days of treatment, malondialdehyde (MDA) and histamine levels as well as the tensile strength of the wound tissue were measured. Structural alterations in epidermis and dermis were histologically evaluated.The locally administreated taurine significantly increased wound tensile strength by decreasing the MDA and histamine levels and prevented the degranulation of the mast cells. These observations suggest that taurine may be useful on wound healing. 相似文献
9.
Takao Sibaoka 《Journal of plant research》1997,110(4):485-487
A wound stimulus evoked a number of repetivite action potentials in the leaf ofBiophytum sensitivum. When the cut end of a leaf was immersed in a leaf extract, the resulting repetitive action potentials continue for a long
time. These repetitive action potentials disappeared immediately when the leaf extract, which contains a proposed stimulant,
was removed and the cut end was washed with water. 相似文献
10.
Summary Wound repair and proliferation were examined in the injured newt atrium with light- and electron-microscopic techniques including autoradiography. Hearts were injured by removing a piece approximately 0.5 mm2 of the atrial wall. The five-day wound was an endothelial and mesothelial-lined blood clot bordered by a 150-m necrotic zone. Repair progressed from the periphery inward with areas of macrophage activity replaced by fibroblasts and connective tissue. The wound at 25 days consisted of a scar with few myocytes. There was no difference in the proliferative behavior between the right and left atria. Proliferative cells were localized to a 500-m reactive zone surrounding the wound. The maximum mesothelial cell thymidine-labeling index of 20.5% and mitotic index of 1.4% were seen 5 days after injury. The peak connective tissue cell thymidine-labeling index of 10.2% and mitotic index of 0.4% were seen 10 days after wounding. The peak thymidine-labeling index of 9.8% for myocardial cells was recorded 10 days after injury with a mitotic index of 0.2%. Proliferation returned to control levels by 25 days post-injury. Electron microscopy demonstrated that myocytes engaged in DNA synthesis were indistinguishable from control myocytes. Z-band material was not observed in mitotic myocytes, but myofilaments and junctions were present. 相似文献