AtxA, a neurotoxic PLA2 from the venom of Vipera a. ammodytes, was conjugated to a nanogold particle and inoculated into the antero-lateral aspect of one hind limb of female mice. Eight hours later the mice were killed and the soleus muscles prepared for transmission electron microscopy. The results suggest that the presynaptic neurotoxicity of snake venom PLA2 involves several components of the neuromuscular apparatus, including intracellular organelles of the motor nerve terminal.
COBISS.SI-ID: 22771239
We showed that calmodulin (CaM) behaves as an activator of Atx, a snake venom sPLA2, under both nonreducing and reducing (cytosol-like) conditions. Kinetic analysis revealed that CaM influences both the catalytic and the vesicle binding properties of the enzyme. Upon exposure to cytosol-like conditions, Atx undergoes a slow hysteretic transition to a less active state. CaM stabilizes the conformation of Atx and thereby restores its activity. These results provide insights into the neurotoxic action of Atx and the mechanisms involved in the regulation of sPLA2s activity within the cytosol.
COBISS.SI-ID: 23138087
The cystatin superfamily comprises cysteine protease inhibitors that play key regulatory roles in protein degradation processes. We traced the genesis and expansion of the cystatin superfamily through comparative genomic and phylogenomic analyses, using publicly available whole-genome information from more than 2100 prokaryotic and eukaryotic genomes, and from the numerous transcriptomic and proteomic databases. This study challenges the current view on the classification, origin and evolution of the cystatin superfamily and provides valuable insights into their functional diversification.
COBISS.SI-ID: 23152679
Imaging-based phenotypic analysis is becoming one of the most important areas of development in functional genomics. In the paper we described an imaging-based method in intact cells to screen yeast mutant libraries for abnormal morphology and distribution of fluorescently labelled organelles, peroxisomes. The study resulted in the identification of two novel proteins, as well as of all previously known proteins required for import of proteins into yeast peroxisomes. This is thus a pioneering study demonstrating the utility of a highly accurate genome-wide image-based screening method.
COBISS.SI-ID: 22360871
Paper describes an all-atom molecular dynamics simulation study of processes in lipid bilayers with different cholesterol/sphingomyelin molar ratios. Results revealed structural and dynamical changes, suggesting that the random distribution of lipids along the bilayer planes is supplanted by the formation of the liquid ordered phase at concentrations of )30 mol% cholesterol. The found critical cholesterol content corresponds well with literature experimental data on formation of the lipid lo-phase, however, it also coincides with ostreolysin binding to such cholesterol-enriched lipid bilayers.
COBISS.SI-ID: 4303642