Lipoprotein-associated phospholipase A(2) : review of its role as a marker and a potential participant in coronary endothelial dysfunction

The role of inflammation in atherosclerosis continues to emerge. Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)), a novel plasma biomarker, circulates in the blood bound mainly to low-density lipoprotein (LDL) and promotes vascular inflammation. Several epidemiological studies have shown that circulating levels of Lp-PLA(2) are an independent risk factor for cardiovascular events. Recent studies demonstrate that Lp-PLA(2) is also associated with endothelial dysfunction and early atherosclerosis. This review provides an overview of these studies, suggests plausible mechanisms for the association between endothelial dysfunction and Lp-PLA(2), and highlights future potential therapies.     

Flowers respond to pollinator sound within minutes by increasing nectar sugar concentration

Can plants sense natural airborne sounds and respond to them rapidly? We show that Oenothera drummondii flowers, exposed to playback sound of a flying bee or to synthetic sound signals at similar frequencies, produce sweeter nectar within 3 min, potentially increasing the chances of cross pollination. We found that the flowers vibrated mechanically in response to these sounds, suggesting a plausible mechanism where the flower serves as an auditory sensory organ. Both the vibration and the nectar response were frequency‐specific: the flowers responded and vibrated to pollinator sounds, but not to higher frequency sound. Our results document for the first time that plants can rapidly respond to pollinator sounds in an ecologically relevant way. Potential implications include plant resource allocation, the evolution of flower shape and the evolution of pollinators sound. Finally, our results suggest that plants may be affected by other sounds as well, including anthropogenic ones.     

Deciphering Axonal Pathways of Genetically Defined Groups of Neurons in the Chick Neural Tube Utilizing in ovo Electroporation

Employment of enhancer elements to drive expression of reporter genes in neurons is a widely used paradigm for tracking axonal projection. For tracking axonal projection of spinal interneurons in vertebrates, germ line-targeted reporter genes yield bilaterally symmetric labeling. Therefore, it is hard to distinguish between the ipsi- and contra-laterally projecting axons. Unilateral electroporation into the chick neural tube provides a useful means to restrict expression of a reporter gene to one side of the central nervous system, and to follow axonal projection on both sides ^{1 ,2-5}. This video demonstrates first how to handle the eggs prior to injection. At HH stage 18-20, DNA is injected into the sacral level of the neural tube, then tungsten electrodes are placed parallel to the embryo and short electrical pulses are administered with a pulse generator. The egg is sealed with tape and placed back into an incubator for further development. Three days later (E6) the spinal cord is removed as an open book preparation from embryo, fixed, and processed for whole mount antibody staining. The stained spinal cord is mounted on slide and visualized using confocal microscopy.     

Iontophoretic Terbinafine HCL 1.0% Delivery Across Porcine and Human Nails

Background  

Onychomycosis is a common disease. Topical treatment is usually not effective due to limitation of trans-nail delivery of antifungal drugs. Successful treatment of deep-seated nail infections remains elusive as the delivery of efficacious levels of antifungal drug to the site of action is very difficult.     

Toxoplasma gondii Toc75 Functions in Import of Stromal but not Peripheral Apicoplast Proteins

Apicomplexa are unicellular parasites causing important human and animal diseases, including malaria and toxoplasmosis. Most of these pathogens possess a relict but essential plastid, the apicoplast. The apicoplast was acquired by secondary endosymbiosis between a red alga and a flagellated eukaryotic protist. As a result the apicoplast is surrounded by four membranes. This complex structure necessitates a system of transport signals and translocons allowing nuclear encoded proteins to find their way to specific apicoplast sub‐compartments. Previous studies identified translocons traversing two of the four apicoplast membranes. Here we provide functional support for the role of an apicomplexan Toc75 homolog in apicoplast protein transport. We identify two apicomplexan genes encoding Toc75 and Sam50, both members of the Omp85 protein family. We localize the respective proteins to the apicoplast and the mitochondrion of Toxoplasma and Plasmodium. We show that the Toxoplasma Toc75 is essential for parasite growth and that its depletion results in a rapid defect in the import of apicoplast stromal proteins while the import of proteins of the outer compartments is affected only as the secondary consequence of organelle loss. These observations along with the homology to Toc75 suggest a potential role in transport through the second innermost membrane.     

Lipid kinases are essential for apicoplast homeostasis in Toxoplasma gondii

Phosphoinositides regulate numerous cellular processes by recruiting cytosolic effector proteins and acting as membrane signalling entities. The cellular metabolism and localization of phosphoinositides are tightly regulated by distinct lipid kinases and phosphatases. Here, we identify and characterize a unique phosphatidylinositol 3 kinase (PI3K) in Toxoplasma gondii, a protozoan parasite belonging to the phylum Apicomplexa. Conditional depletion of this enzyme and subsequently of its product, PI(3)P, drastically alters the morphology and inheritance of the apicoplast, an endosymbiotic organelle of algal origin that is a unique feature of many Apicomplexa. We searched the T. gondii genome for PI(3)P‐binding proteins and identified in total six PX and FYVE domain‐containing proteins including a PIKfyve lipid kinase, which phosphorylates PI(3)P into PI(3,5)P₂. Although depletion of putative PI(3)P‐binding proteins shows that they are not essential for parasite growth and apicoplast biology, conditional disruption of PIKfyve induces enlarged apicoplasts, as observed upon loss of PI(3)P. A similar defect of apicoplast homeostasis was also observed by knocking down the PIKfyve regulatory protein ArPIKfyve, suggesting that in T. gondii, PI(3)P‐related function for the apicoplast might mainly be to serve as a precursor for the synthesis of PI(3,5)P₂. Accordingly, PI3K is conserved in all apicomplexan parasites whereas PIKfyve and ArPIKfyve are absent in Cryptosporidium species that lack an apicoplast, supporting a direct role of PI(3,5)P₂ in apicoplast homeostasis. This study enriches the already diverse functions attributed to PI(3,5)P₂ in eukaryotic cells and highlights these parasite lipid kinases as potential drug targets.     

Increased sugar concentration in response to a wide range of pollinator sounds can be adaptive for the plant: answer to Raguso et al

In Veits et al., we showed that flowers respond to a range of pollinator sounds by increased nectar sugar concentration. Here we clarify that (1) our argument is relevant to most pollinators, and not limited to bees (2) specifically, bees do access Oenothera Drumondii nectar in this area.