Sequencing type material resolves the identity and distribution of the generitype Lithophyllum incrustans,and related European species L. hibernicum and L. bathyporum (Corallinales,Rhodophyta)

DNA sequences from type material in the nongeniculate coralline genus Lithophyllum were used to unambiguously link some European species names to field‐collected specimens, thus providing a great advance over morpho‐anatomical identifi‐cation. In particular, sequence comparisons of rbcL, COI and psbA genes from field‐collected specimens allowed the following conclusion: the generitype species, L. incrustans, occurs mostly as subtidal rhodoliths and crusts on both Atlantic and Mediterranean coasts, and not as the common, NE Atlantic, epilithic, intertidal crust reported in the literature. The heterotypic type material of L. hibernicum was narrowed to one rhodolith belonging in Lithophyllum. As well as occurring as a subtidal rhodolith, L. hibernicum is a common, epilithic and epizoic crust in the intertidal zone from Ireland south to Mediterranean France. A set of four features distinguished L. incrustans from L. hibernicum, including epithallial cell diameter, pore canal shape of sporangial conceptacles and sporangium height and diameter. An rbcL sequence of the lectotype of Lithophyllum bathyporum, which was recently proposed to accommodate Atlantic intertidal collections of L. incrustans, corresponded to a distinct taxon hitherto known only from Brittany as the subtidal, bisporangial, lectotype, but also occurs intertidally in Atlantic Spain. Specimens from Ireland and France morpho‐anatomically identified as L. fasciculatum and a specimen from Cornwall likewise identified as L. duckerae were resolved as L. incrustans and L. hibernicum, respectively.     

Diversity,biogeography and host specificity of kelp endophytes with a focus on the genera Laminarionema and Laminariocolax (Ectocarpales,Phaeophyceae)

Endophytic filamentous brown algae are known to invade stipes and fronds of kelps with potentially negative effects for the hosts. They have simple filamentous thalli and are difficult to identify based on morphology. We investigated the molecular diversity of 56 endophytes isolated from seven different kelp species from Europe, Chile, Korea and New Zealand by sequencing two unlinked molecular markers (5’COI and ITS1). A majority of 49 of the isolated endophytes (88%) belonged to the genera Laminarionema and Laminariocolax. The endophyte Laminarionema elsbetiae was isolated from Saccharina latissima and S. japonica tissues in Europe and Korea, respectively, and showed highly similar sequences in both regions. Three different species of the genus Laminariocolax were identified, the most common of which was L. aecidioides, an endophyte with a worldwide distribution and a broad host range. The other two species, L. tomentosoides and a species described here as Laminariocolax atlanticus sp. nov., were associated with different kelp species in the northern hemisphere and the North Atlantic, respectively. Our results suggest that specific host-endophyte patterns could exist locally, as found in kelps in Brittany where all endophytes isolated from S. latissima were L. elsbetiae, all endophytes isolated from Laminaria digitata were Laminariocolax tomentosoides, and those isolated from Laminaria hyperborea were Laminariocolax atlanticus and L. aecidioides. However, this pattern was not consistent with the results from other places, such as Western Scotland and Helgoland where the same kelp species are present.     

Eosinophils and Megakaryocytes Support the Early Growth of Murine MOPC315 Myeloma Cells in Their Bone Marrow Niches

Multiple myeloma is a bone marrow plasma cell tumor which is supported by the external growth factors APRIL and IL-6, among others. Recently, we identified eosinophils and megakaryocytes to be functional components of the micro-environmental niches of benign bone marrow plasma cells and to be important local sources of these cytokines. Here, we investigated whether eosinophils and megakaryocytes also support the growth of tumor plasma cells in the MOPC315.BM model for multiple myeloma. As it was shown for benign plasma cells and multiple myeloma cells, IL-6 and APRIL also supported MOPC315.BM cell growth in vitro, IL-5 had no effect. Depletion of eosinophils in vivo by IL-5 blockade led to a reduction of the early myeloma load. Consistent with this, myeloma growth in early stages was retarded in eosinophil-deficient ΔdblGATA-1 mice. Late myeloma stages were unaffected, possibly due to megakaryocytes compensating for the loss of eosinophils, since megakaryocytes were found to be in contact with myeloma cells in vivo and supported myeloma growth in vitro. We conclude that eosinophils and megakaryocytes in the niches for benign bone marrow plasma cells support the growth of malignant plasma cells. Further investigations are required to test whether perturbation of these niches represents a potential strategy for the treatment of multiple myeloma.     

Tracking Functional Brain Changes in Patients with Depression under Psychodynamic Psychotherapy Using Individualized Stimuli

Objective

Neurobiological models of depression posit limbic hyperactivity that should normalize after successful treatment. For psychotherapy, though, brain changes in patients with depression show substantial variability. Two critical issues in relevant studies concern the use of unspecific stimulation experiments and relatively short treatment protocols. Therefore changes in brain reactions to individualized stimuli were studied in patients with depression after eight months of psychodynamic psychotherapy.

Methods

18 unmedicated patients with recurrent major depressive disorder were confronted with individualized and clinically derived content in a functional MRI experiment before (T1) and after eight months (T2) of psychodynamic therapy. A control group of 17 healthy subjects was also tested twice without intervention. The experimental stimuli were sentences describing each participant''s dysfunctional interpersonal relationship patterns derived from clinical interviews based on Operationalized Psychodynamic Diagnostics (OPD).

Results

At T1 patients showed enhanced activation compared to controls in several limbic and subcortical regions, including amygdala and basal ganglia, when confronted with OPD sentences. At T2 the differences in brain activity between patients and controls were no longer apparent. Concurrently, patients had improved significantly in depression scores.

Conclusions

Using ecologically valid stimuli, this study supports the model of limbic hyperactivity in depression that normalizes after treatment. Without a control group of untreated patients measured twice, though, changes in patients'' brain activity could also be attributed to other factors than psychodynamic therapy.     

A novel reporter system for bacterial and mammalian cells based on the non-ribosomal peptide indigoidine

The biosynthesis of non-ribosomal peptides, many of which have pharmaceutical activities, is an evolutionary privilege of microorganisms. Capitalizing on the universal set of the Streptomyces lavendulae non-ribosomal peptide synthase BpsA and the Streptomyces verticillus 4'-phosphopantetheinyl transferase Svp, we have engineered Escherichia coli as well as mammalian cells, including human stem cells, to produce the blue 3,3'-bipyridyl pigment keto-indigoidine and the reduced colorless but fluorescent leuco-isoform. Detailed characterization of a tailored substrate-free chromogenic assay and FACS analysis showed that indigoidine's blue color and fluorescence could be reliably profiled in bacteria and mammalian cells using standard multiwell-compatible detection equipment. Besides serving as an inexpensive, reliable, versatile and easy-to-assay cross-kingdom reporter system, the potential of having mammalian cells produce non-ribosomal peptides, preferably ones with biopharmaceutical activities, may provide novel treatment opportunities in future gene- and cell-based therapies.     

Basics in paleodemography: a comparison of age indicators applied to the early medieval skeletal sample of Lauchheim

Recent advances in the methods of skeletal age estimation have rekindled interest in their applicability to paleodemography. The current study contributes to the discussion by applying several long established as well as recently developed or refined aging methods to a subsample of 121 adult skeletons from the early medieval cemetery of Lauchheim. The skeletal remains were analyzed by 13 independent observers using a variety of aging techniques (complex method and other multimethod approaches, Transition Analysis, cranial suture closure, auricular surface method, osteon density method, tooth root translucency measurement, and tooth cementum annulation counting). The age ranges and mean age estimations were compared and results indicate that all methods showed smaller age ranges for the younger individuals, but broader age ranges for the older age groups.     

The functional role of the second NPXY motif of the LRP1 beta-chain in tissue-type plasminogen activator-mediated activation of N-methyl-D-aspartate receptors

The low density lipoprotein receptor-related protein 1 (LRP1) emerges to play fundamental roles in cellular signaling pathways in the brain. One of its prominent ligands is the serine proteinase tissue-type plasminogen activator (tPA), which has been shown to act as a key activator of neuronal mitogen-activated protein kinase pathways via the N-methyl-D-aspartate (NMDA) receptor. However, here we set out to examine whether LRP1 and the NMDA receptor might eventually act in a combined fashion to mediate tPA downstream signaling. By blocking tPA from binding to LRP1 using the receptor-associated protein, we were able to completely inhibit NMDA receptor activation. Additionally, inhibition of NMDA receptor calcium influx with MK-801 resulted in dramatic reduction of tPA-mediated downstream signaling. This indicates a functional interaction between the two receptors, since both experimental approaches resulted in strongly reduced calcium influx and Erk1/2 phosphorylation. Additionally, we were able to inhibit Erk1/2 activation by competing for the LRP1 C-terminal binding motif with a truncated PSD95 construct resembling its PDZ III domain. Furthermore, we identified the distal NPXY amino acid motif in the C terminus of LRP1 as the crucial element for LRP1-NMDA receptor interaction via the adaptor protein PSD95. These results provide new insights into the mechanism of a tPA-induced, LRP1-mediated gating mechanism for NMDA receptors.     

Interaction of Xiphophorus and murine Fyn with focal adhesion kinase

The Src family kinase/Focal Adhesion Kinase (FAK) complex is a signaling platform playing a crucial role in transformation downstream of oncogenic growth factor receptors. In the case of melanoma in Xiphophorus fish, the oncogenic EGF receptor orthologue Xiphophorus melanoma receptor kinase (Xmrk) effects continuous activation of the Src family kinase Fyn, but not of the other family members Src or Yes. Here, Fyn is strongly involved in promoting many tumorigenic events. Although Fyn is expressed in most mammalian tissues, there are only few reports of its involvement in the development of solid tumors. To find out whether the prominent role of Xiphophorus Fyn is based on an altered binding to its important binding partner FAK when compared to its mammalian Fyn counterparts, we performed yeast-two-hybrid analyses. We compared Xiphophorus and murine Fyn with respect to their binding to full-length and truncated FAK constructs. We found that interaction with FAK occurs similarly for Xiphophorus and mouse Fyn. Both phosphorylated FAK residue Y397 and FAK proline-rich domain are involved in Fyn binding. We also found interaction of FAK and Fyn in human melanoma cell lines. These data suggest a possible, yet unrecognized role of Fyn in the tumorigenesis of human melanoma, too.     

Lineage-specific co-evolution of the Egf receptor/ligand signaling system

Background  

The epidermal growth factor receptor (Egfr) with its numerous ligands has fundamental roles in development, cell differentiation and physiology. Dysfunction of the receptor-ligand system contributes to many human malignancies. Consistent with such various tasks, the Egfr gene family has expanded during vertebrate evolution as a consequence of several rounds of whole genome duplication. Of particular interest is the effect of the fish-specific whole genome duplication (FSGD) on the ligand-receptor system, as it has supplied this largest group of vertebrates with additional opportunities for sub- and/or neofunctionalization in this signaling system.