The likely impact of elevated [CO2], nitrogen deposition, increased temperature and management on carbon sequestration in temperate and boreal forest ecosystems: a literature review

Temperate and boreal forest ecosystems contain a large part of the carbon stored on land, in the form of both biomass and soil organic matter. Increasing atmospheric [CO2], increasing temperature, elevated nitrogen deposition and intensified management will change this C store. Well documented single-factor responses of net primary production are: higher photosynthetic rate (the main [CO2] response); increasing length of growing season (the main temperature response); and higher leaf-area index (the main N deposition and partly [CO2] response). Soil organic matter will increase with increasing litter input, although priming may decrease the soil C stock initially, but litter quality effects should be minimal (response to [CO2], N deposition, and temperature); will decrease because of increasing temperature; and will increase because of retardation of decomposition with N deposition, although the rate of decomposition of high-quality litter can be increased and that of low-quality litter decreased. Single-factor responses can be misleading because of interactions between factors, in particular those between N and other factors, and indirect effects such as increased N availability from temperature-induced decomposition. In the long term the strength of feedbacks, for example the increasing demand for N from increased growth, will dominate over short-term responses to single factors. However, management has considerable potential for controlling the C store.     

Purification and characterisation of a jacalin-related, coleoptile specific lectin from Hordeum vulgare

A plant lectin was isolated from barley (Hordeum vulgare) coleoptiles using acidic extraction and different chromatographic methods. Sequencing of more than 50% of the protein sequence by Edman degradation confirmed a full-length cDNA clone. The subsequently identified open reading frame encodes for a 15 kDa protein which could be found in the soluble fraction of barley coleoptiles. This protein exhibited specificity towards mannose sugar and is therefore, accordingly named as Horcolin (Hordeum vulgare coleoptile lectin). Database searches performed with the Horcolin protein sequence revealed a sequence and structure homology to the lectin family of jacalin-related lectins. Together with its affinity towards mannose, Horcolin is now identified as a new member of the mannose specific subgroup of jacalin-related lectins in monocot species. Horcolin shares a high amino acid homology to the highly light-inducible protein HL#2 and, in addition to two methyl jasmonic acid-inducible proteins of 32.6 and 32.7 kDa where the jasmonic acid-inducible proteins are examples of bitopic chimerolectins containing a dirigent and jacalin-related domain. Immunoblot analysis with a cross-reactive anti-HL#2 antibody in combination with Northern blot analysis of the Horcolin cDNA revealed tissue specific expression of Horcolin in the coleoptiles. The function of Horcolin is discussed in the context of its particular expression in coleoptiles and is then compared to other lectins, which apparently share a related response to biotic or abiotic stress factors.     

Effects on neurite outgrowth and cell survival of a secreted fibroblast growth factor binding protein upregulated during spinal cord injury

The fibroblast growth factor binding protein (FGF-BP; GenBank accession no. NP_005121) is a secreted protein that mobilizes FGFs from the extracellular matrix, protects them from degradation, and enhances their biological activity. Several previous studies reported that FGF-BP is an early response gene upregulated during tissue repair processes including wound healing and atherogenesis. In this study we analyzed whether FGF-BP expression was impacted by spinal cord injury and could have an effect on neuronal cell viability. Immunohistochemical and in situ hybridization studies revealed a dramatic upregulation of FGF-BP protein and mRNA levels following unilateral hemisection and contusion injury of adult rat spinal cord. In spinal cord sections of laminectomized rats, increased FGF-BP expression was observed in the fibers and cell bodies ipsilateral to the lesion site but was absent in the uninjured spinal cord tissue contralateral to the lesion. Increased expression of FGF-BP was observed at all postinjury time points, examined with peak levels occurring at day 4, a time when injury-induced increased levels of FGF2 have also been reported to be maximal. Moreover, using PC12 cells as a neuronal model, we observed that exogenous FGF-BP increased the capacity of FGF2 to stimulate neurite outgrowth and to increase cell survival. At the molecular level, FGF-BP enhanced FGF2-induced protein tyrosine phosphorylation and AKT/PKB activation. Collectively, these results suggest that FGF-BP is an early response gene after spinal cord injury and that its upregulation in regenerating spinal cord tissue may provide a molecular mechanism for enhancing the initial FGF2-mediated neurotrophic effects occurring after such tissue damage.     

Spiralian phylogenomics supports the resurrection of Bryozoa comprising Ectoprocta and Entoprocta

Phylogenetic analyses based on 79 ribosomal proteins of 38 metazoans, partly derived from 6 new expressed sequence tag projects for Ectoprocta, Entoprocta, Sipuncula, Annelida, and Acanthocephala, indicate the monophyly of Bryozoa comprising Ectoprocta and Entoprocta, 2 taxa that have been separated for more than a century based on seemingly profound morphological differences. Our results also show that bryozoans are more closely related to Neotrochozoa, including molluscs and annelids, than to Syndermata, the latter comprising Rotifera and Acanthocephala. Furthermore, we find evidence for the position of Sipuncula within Annelida. These findings suggest that classical developmental and morphological key characters such as cleavage pattern, coelomic cavities, gut architecture, and body segmentation are subject to greater evolutionary plasticity than traditionally assumed.     

Compartmentalised expression of <Emphasis Type="Italic">Delta-like 1</Emphasis> in epithelial somites is required for the formation of intervertebral joints

Background  

Expression of the mouse Delta-like 1 (Dll1) gene in the presomitic mesoderm and in the caudal halves of somites of the developing embryo is required for the formation of epithelial somites and for the maintenance of caudal somite identity, respectively. The rostro-caudal polarity of somites is initiated early on within the presomitic mesoderm in nascent somites. Here we have investigated the requirement of restricted Dll1 expression in caudal somite compartments for the maintenance of rostro-caudal somite polarity and the morphogenesis of the axial skeleton. We did this by overexpressing a functional copy of the Dll1 gene throughout the paraxial mesoderm, in particular in anterior somite compartments, during somitogenesis in transgenic mice.     

Selection of vimentin-specific antibodies from the HuCAL phage display library by subtractive panning on formalin-fixed, paraffin-embedded tissue

We describe the direct isolation of specific antibodies on formalin-fixed, paraffin-embedded (FFPE) tissue. The technique involves subtractive selection of a large and highly diverse combinatorial human antibody phage library (HuCAL) on lymphocyte FFPE tissue sections. Tissue sections from normal human tonsil tissue were used to deplete the library of binders to most housekeeping proteins. Mantle-cell lymphoma tissue was used for positive selection and enrichment of mantle cell or tumor-specific antibody phage. We established a high-throughput immunohistochemical method for screening of antibody clones selected from FFPE tissue. One recombinant antibody showed specific staining for interfollicular and mantle cells in FFPE tissue. Immunoprecipitation with this antibody and subsequent mass spectrometric analysis revealed specificity for vimentin.     

Synthesis and in vitro hydroxyapatite binding of peptides conjugated to calcium-binding moieties

To confer bone-binding properties to proteins and other biological agents that lack specific targeting capacity, model peptide-based molecules were synthesized containing poly(aspartic acid), poly(glutamic acid), or a bisphosphonate (pamidronate). These motifs have well-documented affinities to hydroxyapatite, a property desirable for the targeting of molecules to bone for drug delivery and tissue engineering applications. Model peptides of increasing molecular mass (5-33 amino acids) were directly conjugated to eight aspartic acids (Asp8), eight glutamic acids (Glu8), or pamidronate, purified by high-performance liquid chromatography, and characterized by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectroscopy. The modified peptides were incubated with hydroxyapatite in phosphate-buffered saline at physiological conditions over 24 h. This study revealed a significant amount (>90%) of conjugated peptides adsorbed to the hydroxyapatite as compared to unmodified peptides (<5%). It was found that while there were significant differences between the different hydroxyapatite-binding and control groups for all time points, the size of the peptide had no statistical effect on peptide-hydroxyapatite binding. These results demonstrate that bisphosphonate and oligopeptide conjugates hold great promise for the development of new bioactive molecules for bone-specific applications.