Enhanced Cellular Uptake of G-Rich Oligonucleotides

Abstract

Sequence-dependency of cellular uptake of oligonucleotides into Vero cells has been studied. Cellular uptake of 5′-[³⁵S]-labelled homopolymers decreased in the order (dG)₁₆ >> (dT)₁₆> (dA)₁₆ > (dC)₁₆. The change of two base-pairs (dG → dA) in a dG-rich antisense oligonucleotide with good antiviral activity dramatically decreased cellular uptake and abolished antiviral activity.     

The effect of cereal seed extracts on amylase activity of the rose sawfly,Arge rosae Linnaeus (Hymenoptera: Argidae)

The sawfly, Arge rosae Linnaeus (Hymenoptera: Argidae) is a serious pest of rose plants in a vast area of the world including Iran. Pesticides are applied in order to control in areas where infestation is high. So, there is a need for more environmentally benign alternatives to control this insect pest in urban areas. Therefore, the aim of the current study was to study the effect of cereal seed proteinaceous extracts including wheat and triticale on the insect α-amylase. Wheat and triticale seed proteins as well as fourth instars larvae α-amylase were extracted. The results showed that there are two different α-amylase isoenzymes in the insect gut, one major band and the other minor band, which had optimal activity at alkaline pH (pH 8.0). The effect of five concentrations including 0.42, 0.21, 0.105, 0.05 and 0.025?mg?ml^?1 of each seed extract was tested on α-amylase activity of the larvae gut. At the highest concentration (0.42?mg?ml^?1), wheat seed extract caused 74% inhibition of the enzyme activity while triticale seed extract inhibited 62% enzyme activity. Experiments proved that seed proteinaceous extract affected the enzyme activity in a pH-dependant manner.     

Simultaneous two-photon calcium imaging at different depths with spatiotemporal multiplexing

In vivo two-photon calcium imaging would benefit from the use of multiple excitation beams to increase scanning speed, signal-to-noise ratio and field of view or to image different axial planes simultaneously. Using spatiotemporal multiplexing we circumvented light-scattering ambiguity inherent to deep-tissue multifocal two-photon microscopy. We demonstrate calcium imaging at multiple axial planes in the intact mouse brain to monitor network activity of ensembles of cortical neurons in three spatial dimensions.     

Requirement of podocalyxin in TGF-beta induced epithelial mesenchymal transition

Epithelial mesenchymal transition (EMT) is characterized by the development of mesenchymal properties such as a fibroblast-like morphology with altered cytoskeletal organization and enhanced migratory potential. We report that the expression of podocalyxin (PODXL), a member of the CD34 family, is markedly increased during TGF-β induced EMT. PODXL is enriched on the leading edges of migrating A549 cells. Silencing of podocalyxin expression reduced cell ruffle formation, spreading, migration and affected the expression patterns of several proteins that normally change during EMT (e.g., vimentin, E-cadherin). Cytoskeleton assembly in EMT was also found to be dependent on the production of podocalyin. Compositional analysis of podocalyxin containing immunoprecipitates revealed that collagen type 1 was consistently associated with these isolates. Collagen type 1 was also found to co-localize with podocalyxin on the leading edges of migrating cells. The interactions with collagen may be a critical aspect of podocalyxin function. Podocalyxin is an important regulator of the EMT like process as it regulates the loss of epithelial features and the acquisition of a motile phenotype.