Transformation of chicory and expression of the bacterial uidA and nptll genes in the transgenic regenerants

Transgenic chicory plants were obtained from different explantsco-cultured with Agrobacterium tumefaciens. Among tap-root,leaf and cotyledonary tissues, etiolated cotyledons showed thegreatest competence for transformation. The Agrobacterium strainsused contained either pGSGLUC1 or pTDE4 as a vector which carryboth the neomycin phosphotransferase II gene (nptll) for kanamycinresistance and ß-glucuronidase gene (uidA) under thecontrol of different promoters. Transformation was confirmedby NPTII enzymatic assay, histochemical analysis of GUS activityand DNA hybridization. Transgenic plants expressed both markergenes in root and shoot tissues. In leaves, GUS activity wasexpressed in all tissue types, whatever the nature of the promoter.Nevertheless, variable heterogeneous patterns of expressionwere observed in the different root tissues. Differential expression of the GUS fusions controlled by thedual TR or the CaMV 35S promoters are discussed. Key words: Chicory, genetic transformation, GUS activity, kanamycin resistance     

Defining the Range of Pathogens Susceptible to Ifitm3 Restriction Using a Knockout Mouse Model

The interferon-inducible transmembrane (IFITM) family of proteins has been shown to restrict a broad range of viruses in vitro and in vivo by halting progress through the late endosomal pathway. Further, single nucleotide polymorphisms (SNPs) in its sequence have been linked with risk of developing severe influenza virus infections in humans. The number of viruses restricted by this host protein has continued to grow since it was first demonstrated as playing an antiviral role; all of which enter cells via the endosomal pathway. We therefore sought to test the limits of antimicrobial restriction by Ifitm3 using a knockout mouse model. We showed that Ifitm3 does not impact on the restriction or pathogenesis of bacterial (Salmonella typhimurium, Citrobacter rodentium, Mycobacterium tuberculosis) or protozoan (Plasmodium berghei) pathogens, despite in vitro evidence. However, Ifitm3 is capable of restricting respiratory syncytial virus (RSV) in vivo either through directly restricting RSV cell infection, or by exerting a previously uncharacterised function controlling disease pathogenesis. This represents the first demonstration of a virus that enters directly through the plasma membrane, without the need for the endosomal pathway, being restricted by the IFITM family; therefore further defining the role of these antiviral proteins.     

Inbreeding depression of sperm traits in the zebra finch Taeniopygia guttata

Inbreeding depression, or the reduction in fitness due to mating between close relatives, is a key issue in biology today. Inbreeding negatively affects many fitness‐related traits, including survival and reproductive success. Despite this, very few studies have quantified the effects of inbreeding on vertebrate gamete traits under controlled breeding conditions using a full‐sib mating approach. Here, we provide comprehensive evidence for the negative effect of inbreeding on sperm traits in a bird, the zebra finch Taeniopygia guttata. We compared sperm characteristics of both inbred (pedigree F = 0.25) and outbred (pedigree F = 0) individuals from two captive populations, one domesticated and one recently wild‐derived, raised under standardized conditions. As normal spermatozoa morphology did not differ consistently between inbred and outbred individuals, our study confirms the hypothesis that sperm morphology is not particularly susceptible to inbreeding depression. Inbreeding did, however, lead to significantly lower sperm motility and a substantially higher percentage of abnormal spermatozoa in ejaculate. These results were consistent across both study populations, confirming the generality and reliability of our findings.     

Spatially Distinct Pools of TORC1 Balance Protein Homeostasis

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Semisynthetic Triterpenes Derived from Euphorbia officinarum as Plant Growth Promoters and Inducers of Disease Resistance

This study evaluated the effect of application of the semisynthetic triterpenes 3β-acetoxy-norlup-20-one (F4) and 3-chloro-4α,14α-dimethyl-5α-cholest-8-ene (F6) triterpene derivatives from Euphorbia officinarum on the growth of tomato seedlings under normal conditions and when challenged with the pathogens Verticillium dahliae and Agrobacterium tumefaciens. Foliar spray of F4 and F6 significantly improved growth rate, fresh weight, dry weight, and leaf area. In addition, they enhanced several physiological parameters including photosynthetic pigments, proline content, and nitrate reductase activity. Moreover, they induced H₂O₂ accumulation and increased the activity of several antioxidant enzymes such as catalase, ascorbate peroxidase, and guaiacol peroxidase. They also enhanced disease resistance against V. dahliae and A. tumefaciens. These results suggest that the two semisynthetic triterpenes represent new plant growth regulators and inducers of plant disease resistance.

     

Interactions between Hox-negative cephalic neural crest cells and the foregut endoderm in patterning the facial skeleton in the vertebrate head

The vertebrate face contains bones that differentiate from mesenchymal cells of neural crest origin, which colonize the median nasofrontal bud and the first branchial arches. The patterning of individual facial bones and their relative positions occurs through mechanisms that remained elusive. During the early stages of head morphogenesis, an endodermal cul-de-sac, destined to become Sessel's pouch, underlies the nasofrontal bud. Reiterative outpocketings of the foregut then form the branchial pouches. We have tested the capacity of endoderm of the avian neurula to specify the facial skeleton by performing ablations or grafts of defined endodermal regions. Neural crest cells that do not express Hox genes respond to patterning cues produced regionally in the anterior endoderm to yield distinct skeletal components of the upper face and jaws. However, Hox-expressing neural crest cells do not respond to these cues. Bone orientation is likewise dependent on the position of the endoderm relative to the embryonic axes. Our findings thus indicate that the endoderm instructs neural crest cells as to the size, shape and position of all the facial skeletal elements, whether they are cartilage or membrane bones.     

Synthesis of new pseudonucleosides containing chiral cyclosulfamides as agycone

A series of chiral cyclosulfamides have been synthesized in four steps, starting from N-benzoylaminoacids. Regioselective glycosylation of these pseudopyrimidic heterocycles was carried out after deprotection. Best glycosylation results were obtained by preliminary silylation of cyclosulfamides, and their condensation with a tetraacetylribofuranose and pentaacetylglucopyranose is described, which yielded the pseudonucleosides in a beta-anomeric configuration.