The 'ideology and culture' of the Resistance is contained in the verbal and written utterances of participants, and in the visual testimonies of attitudes and stance which remain to us. The historical survey of the Resistance was considered as contextual, providing a framework for analysis of the literature. In all cases the approach used was close textual analysis, the texts grouped around themes: the fall of France, the Occupation, the beginning of the Resistance, the political development of the Resistance and the Liberation. For the historian, the study of such documents provides, as do other sources, concrete examples of Resistance, including the strength and development of movements, and general statements of intent and policy. The descriptor turns out a long list of journals, from the famous to the obscure in which there are major references to women, their groups and Resistance activities.

Reactive oxygen species (ROS) can act as signaling molecules involved in the acclimation of plants to various abiotic and biotic stresses. However, it is not clear how the generalized increases in ROS and downstream signaling events that occur in response to stressful conditions are coordinated to modify plant growth and development. Previous studies of maize (Zea mays L.) primary root growth under water deficit stress showed that cell elongation is maintained in the apical region of the growth zone but progressively inhibited further from the apex, and that the rate of cell production is also decreased. It was observed that apoplastic ROS, particularly hydrogen peroxide (H2O2), increased specifically in the apical region of the growth zone under water stress, resulting at least partly from increased oxalate oxidase activity in this region. To assess the function of the increase in apoplastic H2O2 in root growth regulation, transgenic maize lines constitutively expressing a wheat oxalate oxidase were utilized in combination with kinematic growth analysis to examine effects of increased apoplastic H2O2 on the spatial pattern of cell elongation and on cell production in well-watered and water-stressed roots. Effects of H2O2 removal (via scavenger pretreatment) specifically from the apical region of the growth zone were also assessed. The results show that apoplastic H2O2 positively modulates cell production and root elongation under well-watered conditions, whereas the normal increase in apoplastic H2O2 in water-stressed roots is causally related to down-regulation of cell production and root growth inhibition. The effects on cell production were accompanied by changes in spatial profiles of cell elongation and in the length of the growth zone. However, effects on overall cell elongation, as reflected in final cell lengths, were minor. These results reveal a fundamental role of apoplastic H2O2 in regulating cell production and root elongation in both well-watered and water-stressed conditions.

Cold-induced inhibition of CO(2) assimilation in maize (Zea mays L.) is associated with a persistent depression of the photochemical efficiency of PSII. However, very limited information is available on PSI photochemistry and PSI-dependent electron flow in cold-stressed maize. The extent of the absorbance change (ΔA(820)) used for in vivo quantitative estimation of photooxidizable P700(+) indicated a 32% lower steady-state oxidation level of the PSI reaction center P700 (P700(+)) in cold-stressed compared with control maize leaves. This was accompanied by a 2-fold faster re-reduction rate of P700(+) in the dark, indicating a higher capacity for cyclic electron flow (CEF) around PSI in cold-stressed maize leaves. Furthermore, the increased PSI-dependent CEF(s) was associated with a much higher stromal electron pool size and 56% lower capacity for state transitions compared with control plants. To examine NADP(H) dehydrogenase (NDH)- and ferredoxin:plastoquinone oxidoreductase (FQR)-dependent CEF in vivo, the post-illumination transient increase of F(o)' was measured in the presence of electron transport inhibitors. The results indicate that under optimal growth conditions the relatively low CEF in the maize mesophyll cells is mostly due to the NDH-dependent pathway. However, the increased CEF in cold-stressed plants appears to originate from the up-regulated FQR pathway. The physiological role of PSI down-regulation, the increased capacity for CEF and the shift of preferred CEF mode in modulating the photosynthetic electron fluxes and distribution of excitation light energy in maize plants under cold stress conditions are discussed.

Analysis of the partitioning of absorbed light energy within PSII into fractions utilised by PSII photochemistry (ΦPSII), thermally dissipated via ΔpH- and zeaxanthin-dependent energy quenching (ΦNPQ) and constitutive non-photochemical energy losses (Φf,D) was performed in control and cold-stressed maize (Zea mays L.) leaves. The estimated energy partitioning of absorbed light to various pathways indicated that the fraction of ΦPSII was twofold lower, whereas the proportion of thermally dissipated energy through ΦNPQ was only 30% higher, in cold-stressed plants compared with control plants. In contrast, Φf,D, the fraction of absorbed light energy dissipated by additional quenching mechanism(s), was twofold higher in cold-stressed leaves. Thermoluminescence measurements revealed that the changes in energy partitioning were accompanied by narrowing of the temperature gap (ΔTM) between S2/3QB- and S2QA- charge recombinations in cold-stressed leaves to 8°C compared with 14.4°C in control maize plants. These observations suggest an increased probability for an alternative non-radiative P680+QA- radical pair recombination pathway for energy dissipation within the reaction centre of PSII in cold-stressed maize plants. This additional quenching mechanism might play an important role in thermal energy dissipation and photoprotection when the capacity for the primary, photochemical (ΦPSII) and zeaxanthin-dependent non-photochemical quenching (ΦNPQ) pathways are thermodynamically restricted in maize leaves exposed to cold temperatures.

An alteration in the secondary metabolism of maize (Zea mays L.) genetically modified with the wheat oxalate oxidase (OxO) gene was observed using HPLC and fluorescence microscopy. Phenolic concentrations in the OxO lines were significantly increased, but DIMBOA synthesis was reduced due to a diversion in the shikimate pathway leading to phenolic and hydroxamic acids. Ferulic acid exhibited the largest increase and accounted for 80.4% of the total soluble phenolics. Transcription of a 13-lipoxygenase gene, coding for a key enzyme involved in the regulation of secondary metabolism, was substantially higher in the OxO line than in the null line. To test whether the high levels of soluble phenolic acids, in particular ferulic acid, contributed to the insect resistance in the OxO maize, ferulic acid was administered in meridic diets to European corn borer (ECB). A significant negative correlation between ferulic acid concentration and ECB larval growth rate was found. Field testing during 2001 showed that OxO maize was more resistant to ECB, with leaf consumption and stalk-tunneling damage significantly reduced by 28-34 and 37-39%, respectively, on all of the OxO lines tested and confirming published 2000 findings.

We present a series of 14 binary vectors suitable for Agrobacterium-mediated transformation of dicotyledonous plants and adaptable for biolistic transformation of monocotyledonous plants. The vector size has been minimized by eliminating all non-essential elements from the vector backbone and T-DNA regions while maintaining the ability to replicate independently. The smallest of the vector series is 6.3 kb and possesses an extensive multiple cloning site with 21 unique restriction endonuclease sites that are compatible with common cloning, protein expression, yeast two-hybrid and other binary vectors. The T-DNA region was engineered using a synthetic designer oligonucleotide resulting in an entirely modular system whereby any vector element can be independently exchanged. The high copy number ColE1 origin of replication has been included to enhance plasmid yield in Escherichia coli. FRT recombination sites flank the selectable marker cassette regions and allow for in planta excision by FLP recombinase. The pORE series consists of three basic types; an 'open' set for general plant transformation, a 'reporter' set for promoter analysis and an 'expression' set for constitutive expression of transgenes. The sets comprise various combinations of promoters (P (HPL), P (ENTCUP2) and P (TAPADH)), selectable markers (nptII and pat) and reporter genes (gusA and smgfp).

Cytochrome f from the psychrophile Chlamydomonas raudensis UWO 241 has a lower thermostability of its c-type heme and an apparent molecular mass that is 7 kDa lower than that of the model mesophilic green alga Chlamydomonas reinhardtii. We combined chloroplast transformation, site-directed mutagensis, and the creation of chimeric fusion constructs to assess the contribution of specific domains and (or) amino acids residues to the structure, stability, and accumulation of cytochrome f, as well as its function in photosynthetic intersystem electron transport. We demonstrate that differences in the amino acid sequence of the small domain and specific charged amino acids in the large domain of cytochrome f alter the physical properties of this protein but do not affect either the thermostability of the c-type heme, the apparent half-life of cytochrome f in the presence of the chloroplastic protein synthesis inhibitor chloramphenicol, or the capacity for photosynthetic intersystem electron transport, measured as e–/P700. However, pulse-labeling with [14C]acetate, combined with immunoblotting, indicated that the negative autoregulation of cytochrome f accumulation observed in mesophilic C. reinhardtii transformed with chimeric constructs from the psychrophile was likely the result of the defective association of the chimeric forms of cytochrome f with the other subunits of the cytochrome b6/f complex native to the C. reinhardtii wild type. These results are discussed in terms of the unique fatty acid composition of the thylakoid membranes of C. raudensis UWO 241 adapted to cold environments.

Cytochrome f from the psychrophile Chlamydomonas raudensis UWO 241 has a lower thermostability of its c-type heme and an apparent molecular mass that is 7 kDa lower than that of the model mesophilic green alga Chlamydomonas reinhardtii. We combined chloroplast transformation, site-directed mutagensis, and the creation of chimeric fusion constructs to assess the contribution of specific domains and (or) amino acids residues to the structure, stability, and accumulation of cytochrome f, as well as its function in photosynthetic intersystem electron transport. We demonstrate that differences in the amino acid sequence of the small domain and specific charged amino acids in the large domain of cytochrome f alter the physical properties of this protein but do not affect either the thermostability of the c-type heme, the apparent half-life of cytochrome f in the presence of the chloroplastic protein synthesis inhibitor chloramphenicol, or the capacity for photosynthetic intersystem electron transport, measured as e-/P700. However, pulse-labeling with [14C]acetate, combined with immunoblotting, indicated that the negative autoregulation of cytochrome f accumulation observed in mesophilic C. reinhardtii transformed with chimeric constructs from the psychrophile was likely the result of the defective association of the chimeric forms of cytochrome f with the other subunits of the cytochrome b6/f complex native to the C. reinhardtii wild type. These results are discussed in terms of the unique fatty acid composition of the thylakoid membranes of C. raudensis UWO 241 adapted to cold environments.

Although cytochrome f from the Antarctic psychrophile, Chlamydomonas raudensis UWO 241, exhibits a lower apparent molecular mass (34 kD) than that of the mesophile C. reinhardtii (41 kD) based on SDS-PAGE, both proteins are comparable in calculated molecular mass and show 79% identity in amino acid sequence. The difference in apparent molecular mass was maintained after expression of petA from both Chlamydomonas species in either E. coli or a C. reinhardtii DeltapetA mutant and after substitution of a unique third cysteine-292 to phenylalanine in the psychrophilic cytochrome f. Moreover, the heme of the psychrophilic form of cytochrome f was less stable upon heating than that of the mesophile. In contrast to C. raudensis, a C. reinhardtii DeltapetA mutant transformed with petA from C. raudensis exhibited the ability to undergo state transitions and a capacity for intersystem electron transport comparable to that of C. reinhardtii wild type. However, the C. reinhardtii petA transformants accumulated lower levels of cytochrome b ( 6 ) /f complexes and exhibited lower light saturated rates of O(2) evolution than C. reinhardtii wild type. We show that the presence of an altered form of cytochrome f in C. raudensis does not account for its inability to undergo state transitions or its impaired capacity for intersystem electron transport as previously suggested. A combined survey of the apparent molecular mass, thermal stability and amino acid sequences of cytochrome f from a broad range of mesophilic species shows unequivocally that the observed differences in cytochrome f structure are not related to psychrophilly. Thus, caution must be exercised in relating differences in amino acid sequence and thermal stability to adaptation to cold environments.

Plant tissue culture media, sterilized through commercial filter membrane units, inhibited plant cell growth and development. Embryogenesis was suppressed in microspore cultures of Brassica napus and anther cultures of Triticum aestivum, and in vitro pollen development was suppressed in B. napus. Inhibition of growth and development occurred on media that had been filter-sterilized in low volumes through non-washed filter membrane units of all brands tested, including Nalgene, Corning, Millipore, and Sartorius membrane products. Similar results were obtained with Costar Transwells and Millipore inserts (Millicell-CM, -HA, and -PCF). These deleterious effects were eliminated by washing the membranes with water followed by a small volume of the medium. Media sterilized by filtration through washed filters produced significant improvements of growth and development of embryos and pollen.

A wheat germin gene, with oxalate oxidase (OxO) activity, can be used as a sensitive reporter gene in both monocot and dicot transformations. Detection of H2O2 generated from OxO oxidation of oxalate provides simple, rapid detection of gene expression. Inexpensive substrates are required for both assays. OxO activity, could be detected histochemically in minutes, without chlorophyll clearing procedures. This assay was used to optimize transformation procedures and to track stable transgene expression in breeding populations over many generations. A simple spectrophotometric quantitative enzyme activity assay was used to select lines with various levels of transgene expression and to monitor transgene silencing phenomena. The quantitative OxO assay can also be used as an internal DNA delivery standard with a second reporter gene used in gene expression studies. The simplicity of the assay is ideal for screening large populations to identify primary transgenics, for monitoring transgene segregation in large populations in field studies and for assessing stability of transgene expression over numerous generations.

The strategy of targeting expression of a constitutively regulated gene to generate H2O2 in the extracellular matrix, to reduce herbivory of the European corn borer (ECB) [Ostrinia nubilalis (Hübner)] was tested by transforming corn with germin, a wheat oxalate oxidase (OXO) gene, regulated by the rice actin promoter elements (pAct-OXO). With two independent transformation events, enzyme activity was stable over seven generations of backcrossing into three maize inbred lines. Enzyme activity remained associated with the cell wall debris fraction of water extracted tissues. Leaf tissue of the germin transgenics had elevated levels of H2O2. In vitro leaf feeding bioassays demonstrated that ECB larvae feeding was significantly reduced and larval growth and development were delayed on all ECB infested germin transgenic lines. This reduced ECB feeding was confirmed under field conditions. Most significantly, stalk tunneling damage, measured at plant harvest, was substantially reduced in all germin transgenic lines. The reduction of tunneling by 50% in the transgenic lines is indicative of lower levels of ECB survival which should be significant in ECB epidemiology. Possible mechanisms of resistance include modifications in plant cell wall chemistry, activation of pathogen resistance genes and effects of H2O2 and germin on insect physiology are discussed.

A limited number of constitutive promoters have been used to direct transgene expression in plants and they are often derived from non-plant sources. Here, we describe novel gene-regulatory elements which are associated with a cryptic constitutive promoter from tobacco, tCUP, and modifications that were made to create a strong gene-expression system that is effective across all living cell types from a wide range of plant species, including several important crops (Arabidopsis, canola, flax, alfalfa, tobacco). The tCUP 5′ untranslated region was mutated to eliminate translational interference by upstream ATGs, and the influence of the Kozak consensus sequence on the levels of a β-glucuronidase (GUS) reporter gene activity was demonstrated. These modifications resulted in expression that was greatly enhanced in all organs. A TATA consensus sequence was added to the core promoter to complement an existing Initiator (Inr) sequence. Although this addition was known to elevate core promoter activity by 3-fold the additive effect on the overall gene-expression system was marginal in all of the transgenic plants tested. Two transcriptional enhancers were identified and the region containing them were oligomerized, yielding a significant increase in marker gene-expression in some but not all plant species. In general, the enhanced tCUP gene-expression system generated levels of GUS activity which exceeded that of the 35S promoter in most plant species and the elevation in activity occurred uniformly among the various plant organs. The potential benefit of cryptic elements for the construction of gene-expression systems for crop species is discussed

Protein kinases play a central role in signal transduction in all organisms and to study signal transduction in response to salt stress we have identified and characterized a gene encoding a protein kinase that is induced by salt stress and abscisic acid (ABA) in the salt-tolerant wild wheatgrass Lophopyrum elongatum (Host) A. Love. The product of the early salt stress-induced gene, Esi47, was found to belong to the "novel Arabidopsis protein kinase" group of plant serine/threonine protein kinases. Transient gene expression assays in barley aleurone tissue showed Esi47 to suppress the gibberellin induction of the barley low-pI alpha-amylase gene promoter, thus providing evidence for the role of this protein kinase gene in plant hormone signaling. Esi47 contains a small upstream open reading frame in the 5'-untranslated region of its transcript that is implicated in mediating the repression of the basal level of the gene expression and in regulating the ABA inducibility of the gene, as shown in the transient gene expression assay in maize callus. Three Arabidopsis homologs of Esi47 were identified, and different members of this clade of genes showed differential patterns of regulation by salt stress and ABA in Arabidopsis roots and leaves. At least one of the Arabidopsis homologs contains a small open reading frame in its 5'-untranslated region, indicating that the unusual regulatory mechanism identified in Esi47 may be widely conserved.