The planarian <Emphasis Type="Italic">nanos</Emphasis>-like gene Smednos is expressed in germline and eye precursor cells during development and regeneration

Planarians are highly regenerative organisms with the ability to remake all their cell types, including the germ cells. The germ cells have been suggested to arise from totipotent neoblasts through epigenetic mechanisms. Nanos is a zinc-finger protein with a widely conserved role in the maintenance of germ cell identity. In this work, we describe the expression of a planarian nanos-like gene Smednos in two kinds of precursor cells namely, primordial germ cells and eye precursor cells, during both development and regeneration of the planarian Schmidtea mediterranea. In sexual planarians, Smednos is expressed in presumptive male primordial germ cells of embryos from stage 8 of embryogenesis and throughout development of the male gonads and in the female primordial germ cells of the ovary. Thus, upon hatching, juvenile planarians do possess primordial germ cells. In the asexual strain, Smednos is expressed in presumptive male and female primordial germ cells. During regeneration, Smednos expression is maintained in the primordial germ cells, and new clusters of Smednos-positive cells appear in the regenerated tissue. Remarkably, during the final stages of development (stage 8 of embryogenesis) and during regeneration of the planarian eye, Smednos is expressed in cells surrounding the differentiating eye cells, possibly corresponding to eye precursor cells. Our results suggest that similar genetic mechanisms might be used to control the differentiation of precursor cells during development and regeneration in planarians. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Complex media from processing of agricultural crops for microbial fermentation

This mini-review describes the concept of the green biorefinery and lists a number of suitable agricultural by-products, which can be used for production of bioenergy and/or biochemicals. A process, in which one possible agricultural by-product from the green crop drying industry, brown juice, is converted to a basic, universal fermentation medium by lactic acid fermentation, is outlined. The resulting all-round fermentation medium can be used for the production of many useful fermentation products when added a carbohydrate source, which could possibly be another agricultural by-product. Two examples of such products—polylactic acid and l-lysine—are given. A cost calculation shows that this fermentation medium can be produced at a very low cost ≈1.7 Euro cent/kg, when taking into account that the green crop industry has expenses amounting to 270,000 Euro/year for disposal of the brown juice. A newly built lysine factory in Esbjerg, Denmark, can benefit from this process by buying a low price medium for the fermentation process instead of more expensive traditional fermentation liquids such as corn steep liquor.     

Gene expression of LOX-1, VCAM-1, and ICAM-1 in pre-atherosclerotic mice

To identify markers of the earliest stage of atherosclerosis, endothelial dysfunction, we evaluated the gene expression of lectin-like oxidized-low-density-lipoprotein receptor-1 (LOX-1), vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) in very young pre-atherosclerotic mice. Furthermore, the plasma levels of the soluble VCAM-1 and ICAM-1 were compared to the gene expression profiles. Gene expressions of LOX-1 and VCAM-1 were up-regulated in young apoE^−/− mice, and thus, it seems probable that these genes play a role in pre-atherosclerosis. Contrarily, the gene expression profile of ICAM-1 did not show any apparent differences between the groups, questioning the involvement of this molecule in the early development of atherosclerosis. Plasma levels of sVCAM-1 and sICAM-1 were similar in all mice and did not correlate with the vascular gene expression of the corresponding genes. It therefore seems likely that these circulating markers are not suited to detect early atherosclerosis.     

Elevated CO2 increases fungal-based micro-foodwebs in soils of contrasting plant species

Plant and Soil - As different plant species support different soil communities, assessment of climate change impacts on soil communities must consider how these impacts depend on the vegetation. We...     

Partial functional complementation between human and mouse cytomegalovirus chemokine receptor homologues

The human cytomegalovirus (CMV) proteins US28 and UL33 are homologous to chemokine receptors (CKRs). Knockout of the mouse CMV M33 protein (UL33 homologue) results in substantial attenuation of salivary gland infection/replication and reduced efficiency of reactivation from tissue explants. M33-mediated G protein-coupled signaling is critical for the salivary gland phenotype. In this report, we demonstrate that US28 and (to a lesser degree) UL33 restore reactivation from tissue explants and partially restore replication in salivary glands (compared to a signaling-deficient M33 mutant). These studies provide a novel small animal model for evaluation of therapies targeting the human CMV CKRs.