Different imaging modalities always have unique strengths and weaknesses. The combination of two popular in vivo imaging methods shows that combining them gives you the best of both.
Researchers present a method to generate protein structures using NMR chemical shift data in combination with powerful modeling software, simplifying and shortening the process of NMR-based structure determination.
Capitalizing on the imperfection of error-prone DNA repair, researchers generated knockout mammalian cell lines by targeting a nuclease to a gene of interest via a zinc-finger DNA-binding domain.
A new antibody to monoubiquitinated histone H2B (ubH2B) allows chromatin immunoprecipitation (ChIP) from mammalian cells to map ubiquitination patterns across the genome or to follow the modification of individual genes.
A high-throughput pipeline to engineer bacterial artificial chromosomes (BACs) expressing tagged genes of higher eukaryotes allows large-scale protein localization and interaction studies.
A spheroid assay that recapitulates angiogenesis in vivo and a ring assay to measure lymphangiogenesis in vitro expand the toolbox of techniques to investigate these processes during development and tumor progression.
Microscopic resolution far beyond the diffraction limit is possible by localizing single molecules individually. This approach has now been demonstrated on living cells.
Low efficiency of transfection limits the ability to genetically manipulate human embryonic stem cells (hESCs), and differences in cell derivation and culture methods require optimization of transfection protocols. We transiently transferred multiple independent hESC lines with different growth requirements to standardized feeder-free culture, and optimized conditions for clonal growth and efficient gene transfer without loss of pluripotency. Stably transfected lines retained differentiation potential, and most lines displayed normal karyotypes.
We present a high-throughput method that enables efficient delivery of biomolecules into cells. The device consists of an array of 96 suspended electrode pairs, where small sample volumes are top-loaded, electroporated and bottom-ejected into 96-well plates. We demonstrate the use of this suspended-drop electroporation (SDE) device to effectively introduce fluorescent dextran, small interfering RNA (siRNA) or cDNA into primary neurons, differentiated neutrophils and other cell types with conventionally low transfection rates.
We describe a method to generate monovalent quantum dots (QDs) using agarose gel electrophoresis. We passivated QDs with a carboxy-terminated polyethylene-glycol ligand, yielding particles with half the diameter of commercial QDs, which we conjugated to a single copy of a high-affinity targeting moiety (monovalent streptavidin or antibody to carcinoembryonic antigen) to label cell-surface proteins. The small size improved access of QD-labeled glutamate receptors to neuronal synapses, and monovalency prevented EphA3 tyrosine kinase activation.
