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Kilian, N.

Publications and source records attributed to Kilian, N..

4 recordsLinked to original sources

A silicon rhodamine-fused glibenclamide to label and detect malaria-infected red blood cells

The malaria parasite Plasmodium falciparum affects the lives of millions of people worldwide every year. The detection of replicating parasites within human red blood cells is of paramount importance, requiring appropriate diagnostic tools. Herein, we design and apply a silicon rhodamine-fused glibenclamide (SiR-glib). We first test this far-red fluorescent, fluorogenic and endoplasmic reticulum-targeting sulfonylurea in mammalian cells and pancreatic tissues, before characterizing its labeling performance in red blood cells infected with the asexual developmental stages of Plasmodium falciparum. We further combine SiR-glib with a portable smartphone-based microscope to easily and rapidly identify parasitized red blood cells, providing proof of principle for diagnostic use in rural endemic areas without major healthcare facilities.

biochemistry↗

KAHRP dynamically relocalizes to remodeled actin junctions and associates with knob spirals in P. falciparum-infected erythrocytes

The knob-associated histidine-rich protein (KAHRP) plays a pivotal role in the pathophysiology of Plasmodium falciparum malaria by forming membrane protrusions in infected erythrocytes, which anchor parasite-encoded adhesins to the membrane skeleton. The resulting sequestration of parasitized erythrocytes in the microvasculature leads to severe disease. Despite KAHRP being an important virulence factor, its physical location within the membrane skeleton is still debated, as is its function in knob formation. Here, we show by super-resolution microscopy that KAHRP initially associates with various skeletal components, including ankyrin bridges, but eventually co-localizes with remnant actin junctions. We further present a 35[A] map of the spiral scaffold underlying knobs and show that a KAHRP-targeting nanoprobe binds close to the spiral scaffold. Single-molecule localization microscopy detected [~]60 KAHRP molecules per knob. We propose a dynamic model of KAHRP organization and a function of KAHRP in attaching other factors to the spiral scaffold.

microbiology↗

Mitochondrial fission governed by Drp1 regulates exogenous fatty acid usage and storage

The bioenergetic function of mitochondrial fission is associated with uncoupled respiration or elimination of damaged mitochondria to maintain a healthy mitochondrial population. In the presence of a high abundance of exogenous fatty acids, cells can either store fatty acids in lipid droplets or oxidize them in mitochondria. Even though carnitine palmitoyltransferase-1 (CPT1) controls the respiratory capacity of mitochondria in fatty acid oxidation, we observed that it did not dictate the balance of storage and usage of lipids in HeLa cells. On the other hand, inhibition of mitochondrial fission by silencing dynamic-related protein 1 (DRP1) resulted in an increase in fatty acid content of lipid droplets and a decrease in fatty acid oxidation. Mitochondrial fission was not only reflective of the amount of exogenous fatty acid being processed by mitochondria, but also found to be actively involved in the distribution of fatty acids between mitochondria and lipid droplets. Our data reveals a novel function for mitochondrial fission in balancing exogenous fatty acids between usage and storage, assigning a role for mitochondrial dynamics in control of intracellular fuel utilization and partitioning.

cell biology↗

Sinoseris (Crepidinae, Cichorieae, Asteraceae), a new genus endemic to China of three species, two of them new to science

Elucidating the systematic position of two Chinese species described originally as Lactuca hirsuta and L. scandens, of which only historical specimens from the late 19th and early 20th century were known, field work confirmed the occurrence of three different species. Molecular phylogenetic analysis of these species based on sequences of the nuclear ribosomal internal transcribed spacer (nrITS) region uncovered a hitherto unknown lineage in a phylogenetic backbone of the subtribe Crepidinae of the sunflower family tribe Cichorieae. Substantiated by comparative morphological studies, this lineage is described as genus new to science, named Sinoseris, endemic to the Chinese provinces Sichuan and Yunnan. Two of its three species are new to science, while the third is conspecific with both L. hirsuta and L. scandens.

plant biology↗