Cell biology Light-activated ion channels for remote control of neuronal firing Banghart et al. describe a specialized chemical gating molecule capable of undergoing light-induced photoisomerization, resulting in the reversible inhibition of ion channel function. They successfully demonstrate the use of the compound, MAL-AZO-QA, to block the action of the voltage-gated Shaker potassium channel in Xenopus laevis oocytes and cultured rat hippocampal neurons.
Banghart, M.et al. Nat. Neurosci., published online 21 November 2004.
Microarrays Printed covalent glycan array for ligand profiling of diverse glycan binding proteins Several different kinds of glycan-based arrays have been developed to assess the specificities of glycan binding proteins (GBPs). Blixt et al. present an approach that enables the generation of such arrays by the same robotic printing process used for DNA arrays. Studies conducted with such arrays show high sensitivity and reproducibility, with consistently low background.
Genomics DNA methylation profiling of the human major histocompatibility complex: A pilot study for the human epigenome project The Human Epigenome Project was launched just over a year ago with the aim of assembling an atlas of DNA methylation within the regulatory regions of all human genes. Rakyan et al. present the outcome of the pilot phase of this project, a DNA methylation profile for the human major histocompatibility complex.
Rakyan, V.K.et al. PLoS Biology, published online 23 November 2004.
Gene transfer Baculovirus expression system for heterologous multiprotein complexes Baculoviral vectors can contain large amounts of exogenous DNA, making them appealing candidates for the assembly of multicistronic expression constructs. Berger et al. describe a 'multiplication module' strategy for the rapid, iterative assembly of multiple promoter-gene sets within a transfer vector, which can then be recombined into a bacmid for efficient expression.
Berger, I.et al. Nat. Biotechnol., published online 28 November 2004.
RNA interference Highly efficient small interfering RNA delivery to primary mammalian neurons induces microRNA-like effects before mRNA degradation Although RNA interference (RNAi) can be an extremely powerful tool for gene silencing, its use in nervous system studies has been limited by the difficulties involved in transfecting neurons. By conjugating the vector peptide Penetratin 1 to their small interfering RNAs, Davidson et al. achieve effective and nontoxic delivery into cultured neurons, and demonstrate successful RNAi for several genes.
