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81.
The gene coding for the green fluorescent protein (GFP) from jellyfish was introduced into conifer tissues by microprojectile bombardment and its transient expression was detected. Two versions of the GFP gene, wild-type GFP and modified GFP with a cryptic intron removed, were directly compared for their expression in black spruce pollen. While the wild-type GFP gene resulted in a low level of expression, the modified GFP gene gave a dramatic increase in amount of expression (>100 times). The expression of GFP was detected in all the tissues tested : pollen, embryonal masses, suspension culture, and somatic embryos. Also, the GFP gene was introduced and expressed in three different conifer species (black spruce, white spruce, and white pine). The successful expression of the GFP gene in various tissues and different species suggests that it will be a useful reporter/marker gene for conifers.Abbreviations GUS
-glucuronidase
- NOS
nopaline synthase
- NPTII
neomycin phosphotransferase
- CaMV
cauliflower mosaic virus
Communicated by S. Gleddie 相似文献
82.
Séguin Armand Laible G?tz Leyva Antonio Dixon Richard A. Lamb Christopher J. 《Plant molecular biology》1997,35(3):281-291
83.
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Recurrent fruit harvesting reduces seedling density but increases the frequency of clonal reproduction in a tropical tree 下载免费PDF全文
Studies on the ecological impacts of non‐timber forest products (NTFP) harvest reveal that plants are often more resilient to fruit and seed harvest than to bark and root harvest. Several studies indicate that sustainable fruit harvesting limits can be set very high (>80% fruit harvesting intensity). For species with clonal and sexual reproduction, understanding how fruit harvest affects clonal reproduction can shed light on the genetic risks and sustainability of NTFP harvest. We studied 18 populations of a gallery forest tree, Pentadesma butyracea (Clusiaceae), to test the impact of fruits harvest, climate and habitat size (gallery forest width) on the frequency of sexual or clonal recruitment in Benin, West Africa. We sampled populations in two ecological regions (Sudanian and Sudano‐Guinean) and in each region, we selected sites with low, moderate and high fruit harvesting intensities. These populations were selected in gallery forests with varying width to sample the natural variation in P. butyracea habitat size. Heavily harvested populations produced significantly less seedlings but had the highest density and proportion of clonal offspring. Our study suggests that for plant species with dual reproductive strategy (via seeds and clonal), fruit harvesting and associated disturbances that come with it can lead to an increase in the proportion of clonal offspring. This raises the issue that excessive fruit harvest by increasing the proportion of clonal offspring to the detriment of seed originated offspring may lead to a reduction in genetic diversity with consequence on harvested species capability to withstand environmental stochasticity. 相似文献
86.
Mixed Phase Solid‐State Plastic Crystal Electrolytes Based on a Phosphonium Cation for Sodium Devices 下载免费PDF全文
Faezeh Makhlooghiazad Daniel Gunzelmann Matthias Hilder Douglas R. MacFarlane Michel Armand Patrick C. Howlett Maria Forsyth 《Liver Transplantation》2017,7(2)
Na batteries are seen as a feasible alternative technology to lithium ion batteries due to the greater abundance of sodium and potentially similar electrochemical behavior. In this work, mixed phase electrolyte materials based on solid‐state compositions of a tri methylisobutylphosphonium (P111i4) bis(tri fluromethanesulphonyl)amide (NTf2) organic ionic plastic crystal (OIPC) and high concentration of NaNTf2 that support safe, sodium metal electrochemistry are demonstrated. A Na symmetric cell can be cycled efficiently, even in the solid state (at 50 °C and 60 °C), for a 25 mol% (P111i4NTf2)–75 mol% NaNTf2 composition at 0.1 mA cm?2 for 100 cycles. Thus, these mixed phase materials can be potentially used in Na‐based devices under moderate temperature conditions. It is also investigated that the phase behavior, conductivity, and electrochemical properties of mixtures of NaNTf2 with this OIPC. It is observed that these mixtures have complex phase behavior. For high compositions of the Na salt, the materials are solid at room temperature and retain a soft solid consistency even at 50 °C with remarkably high conductivity, approaching that of the pure ionic liquid at 50 °C, i.e., 10?3–10?2 S cm?1. 相似文献
87.
88.
Fluorescently labeled type-3 copper proteins have been proposed previously as solution oxygen sensors by using a FRET mechanism. Herein, we describe how this principle can be adapted to sense O2 by means of proteins immobilized in optically transparent silica matrices. Specifically, the protein, hemocyanin from Octopus vulgaris N-terminally labeled with Cy5, is immobilized in two different kinds of optically transparent silica matrices, which appear to be a promising platform for enzyme encapsulation. The presented results provide proof of principle that fluorescently labeled proteins immobilized in a silica matrix can be implemented in a reusable, biocompatible and stable oxygen measuring device that might lead to new developments in the field of optical biosensing. 相似文献
89.
90.
Frank Bedon Caroline Levasseur Jacqueline Grima-Pettenati Armand Séguin John MacKay 《Plant cell reports》2009,28(5):787-800
The enzyme Cinnamyl
Alcohol
Dehydrogenase (CAD) catalyses the last step of lignin monomer synthesis, and is considered as a molecular marker of cell wall lignification
in different plants species. Here, we report the isolation and analysis of 5′ flanking genomic DNA regions upstream to the
CAD gene, from two conifers, i.e. white spruce (Picea
glauca (Moench) Voss) and loblolly pine (Pinus
taeda L.). Sequence comparisons with available CAD gene promoters from angiosperms highlighted the conservation of cis-elements matching MYB, WRKY and bHLH binding sites. Functional characterization of the P.
glauca
CAD promoter used P.
glauca seedlings stably transformed with a DNA fragment of 1,163 base pairs (PgCAD) fused to the β-glucuronidase (GUS) gene. Histochemical observations of different vegetative organs of the transgenic trees showed that this sequence was sufficient
to drive GUS expression in lignifying tissues, and more specifically in differentiating xylem cells. Quantitative RT-PCR experiments
also indicated that the native CAD gene was preferentially expressed in differentiating xylem both in stems and roots. In addition, GUS expression driven by
the PgCAD promoter was wound-inducible which was consistent with the accumulation of CAD mRNA in response to jasmonate application and mechanical wounding. The spruce CAD promoter represents a valuable tool for research and biotechnology applications related to xylem and wood.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献