Research Highlights in 2009

Gold nanoparticles are used to monitor caspase activity at the single-molecule level in living cells.

Researchers observe that cells of the post-implantation mouse epiblast can revert to an embryonic stem cell–like state without the addition of exogenous genes.

New chemical microarrays capture a comprehensive snapshot of the various enzymatic activities contained within a biological sample.

An imaging platform based on stimulated emission helps researchers to lead nonfluorescent chromophores out of the shadows.

Two methods enable the drawing of genome-wide chromatin interaction maps: one looks at protein-independent folding principles, the other at protein-mediated functional interactions.

With a modified polymerase and optimized oligonucleotide chemistry, Helicos' single-molecule sequencer takes on RNA.

Researchers use atomic force microscopy to image the chemical structure of the small molecule pentacene, with atomic resolution.

Certain yeast previously assumed to lack RNA interference machinery instead have alternative enzyme variants, which can in turn be transplanted to truly deficient species.

By monitoring the size-dependence of particle distribution in the lamellipodium, fluid flow in moving cells can be measured.

A new in vivo imaging strategy produces detailed maps of tumor microvasculature and lymphatic vessels without injected labels.

The development of leader sequences that stimulate mRNA translation in a species-independent manner could offer new possibilities for eukaryotic protein production and proteomic research.

Visualization of choline-containing phospholipids in cells and in vivo is made possible by the metabolic incorporation of a choline analog with an alkyne handle for click chemistry–based labeling.

Bacterial genomes shuttled into yeast can be easily altered before transplantation back into bacteria.

Channelrhodopsin-2 can be efficiently activated by infrared two-photon excitation light and stimulates action potentials in cultured neurons.

By fusing a light-sensitive domain of an oat plant protein to Rac1, researchers created a genetically encoded protein fusion that can be reversibly activated with blue light and control cell movement—an attractive alternative to current caging tools.

A phenotype prediction tool helps 'fill in the blanks' for expression microarrays, extending their predictive power and uncovering once-hidden biases.

Researchers develop a strategy to improve the intracellular retention of fluorescent probes and thus their imaging sensitivity.