Volume 6 Issue 5, May 2009

By directly delivering light deep into the brain, scientists can now study the basis of neurological therapy and animal behavior.

Pairing bisulfite conversion of the human genome with targeted enrichment and high-throughput sequencing allows a quantitative assessment of DNA methylation at base-pair resolution.

A new algorithm for identifying evolutionary constraint incorporates information on local DNA topology, and leads to the finding that this topology is conserved across species.

Researchers show that superpositively charged GFP enters mammalian cells with ease and can be used as a nucleic acid delivery vehicle.

Fake fingertips provide insights into how fingerprints help humans to feel fine details of surface texture.

DNA hydrogels improve the efficiency of cell-free protein production.

A transposon-based approach has been added to the growing arsenal of technologies to produce transgene-free and potentially safer induced pluripotent stem cells.

The use of a spatial light modulator for illuminating the sample in structured-illumination microscopy (SIM) increases imaging speed by three orders of magnitude. The resulting 100-nm resolution and 11-Hz frame rate allowed video imaging of tubulin polymerization and depolymerization as well as kinesin movement on microtubules.

The combination of 5′ exonuclease, DNA polymerase and ligase with overlapping DNA fragments facilitates the in vitro assembly of large DNA constructs, including an entire bacterial genome.

Upon binding multiple fluorophores and being complexed into tetramers, these RNA imaging probes show high sensitivity and can detect single endogenous RNA molecules at low probe concentration.

A fluorescent protein, Sirius, with the most blue-shifted emission spectrum to date, is reported. Sirius allows extended multicolor imaging as well as imaging in acidic environments owing to its pH insensitivity.

Several red and orange fluorescent proteins are reported to be photoconvertible. Specifically, three red fluorescent proteins that can be switched to green, and two orange fluorescent proteins that can be switched to far red are reported.

A method, filter-aided sample preparation (FASP) combines the advantages of in-gel and in-solution digestion for mass spectrometry–based proteomics, allowing deeper proteomic coverage in a shorter analysis time, using small sample amounts.

piggyBac transposons carrying reprogramming factors are used to reprogram mouse embryonic fibroblasts, with efficiencies equivalent to retroviral transduction, and then removed from the induced pluripotent state cell genome without a trace.

Lentiviral vectors that express a fluorescent reporter and a selectable marker in pluripotent cells improve and simplify isolation of induced pluripotent stem cell lines in mouse and human.

Previous whole-transcriptome analysis by RNA-Seq required hundreds of thousands of cells or microgram amounts of RNA. A modification of the cDNA library preparation method now allows unbiased capture of the majority of genes expressed in a single blastomere and oocyte. cDNA sequencing on the SOLiD platform facilitates the quantitative analysis of the transcriptome complexity in a single cell.

An atomic force microscope with a side-view fluorescent imaging path facilitates the direct correlation of mechanical force measurements with observations of changes in cell shape and cytoskeleton rearrangements resulting from the applied forces or during active generation of forces by the cell. The combined instrument could help lead to insights in understanding cell mechanics, contractility and cell-cell adhesion.

Surface plasmon resonance sensing has entered the next phase of development as researchers advance array-based applications using the technique. Could these new approaches change the way scientists explore protein interactions?