Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
Du et al. describe a bead-based method for high-throughput detection of phosphorylated tyrosine kinases and use it to profile 130 human cancer lines. They show that the tyrosine kinase SRC is frequently activated in glioblastoma cells and that a SRC inhibitor blocks the growth of glioblastoma tumors.
Foudi et al. report a method for monitoring the turnover of hematopoietic stem cells that has several advantages over BrdU labeling. Using drug-inducible expression of a histone 2B–GFP fusion protein, which permits a more sensitive analysis of division history, the authors detect hematopoietic stem cells that cycle at a very slow rate.
Gene silencing by siRNA generally relies on short RNA duplexes containing two strands of the same length. Sun et al. show that an asymmetric duplex with a shortened passenger strand silences its target gene effectively while reducing off-target effects mediated by this strand.
Fan et al. describe a microfluidic chip for multiplexed analysis of proteins in a finger prick of blood. The chip separates plasma from diluted whole blood and quantifies panels of serum proteins in about 10 minutes, minimizing protein degradation.
Fruit-specific overexpression of a pair of snapdragon transcription factors produces tomatoes that uniformly accumulate anthocyanins at levels unprecedented for metabolic engineering. When included as a dietary supplement, the purple tomatoes increase the life spans of tumorigenic p53 knockout mice.
The HIV-1 protein Vif, which promotes degradation of the host cell's antiviral APOBEC3 proteins, has yet to be targeted for therapeutic intervention. Nathans et al. use a high-throughput fluorescence screen to identify a small molecule that inhibits HIV replication in cultured cells by antagonizing Vif in an APOBEC3-dependent manner.
The current reversibly switchable fluorescent proteins (RSFPs) can not be multiplexed. Jakobs and colleagues create two RSFPs with novel switching characteristics that can be used simultaneously in fluorescence microscopy experiments using only one detection color.
PDZ domains represent one of the largest families of interaction domains. Chen et al. develop a scoring matrix that enables prediction of peptide–PDZ domain interactions. Unlike previous methods, the model works to some extent for PDZ domains that were not part of the training set.
Metagenomics, or shotgun sequencing of environmental DNA, is used to study complex microbial communities. Kalyuzhnaya et al. describe a method for targeting specific microbial subpopulations in environmental samples and use it to analyze microbes that metabolize C1 compounds.
Microarray platforms usually rely on fluorescence detection. Clack et al. present an equally sensitive, label-free technique that electrostatically detects DNA or RNA hybridization after randomly dispersing charged microspheres onto the microarray surface.
The targets of a microRNA (miRNA) are usually identified by computational analysis of sequences complementary to the miRNA. Working with inflorescence tissue of Arabidopsis, German et al. devise an experimental approach in which the products of miRNA-mediated cleavage are sequenced and used to identify miRNA–target RNA pairs.