In an early online publication, James Thomson has derived human iPS cells using non-integrating episomal vectors. After removing the episome, his team was able to derive iPS cells that were free of vector and transgene sequences and that were similar to human embryonic stem cells.
Scientists have found genes that are critical for protein folding in the endoplasmic reticulum. Studying the unfolded protein response, they found several hundred yeast genes with roles in endoplasmic reticulum folding. Using double mutants, they characterized several involved, including genes in the later secretory pathway, a six-protein transmembrane complex, and a co-chaperone complex.
At the Mount Sinai School of Medicine, researchers have used a combination of imaging techniques to visualize HIV transfer across virological synapses. Using a fluorescent clone of HIV, they tracked the movement of Gag in CD4 T cells and watched HIV move across the synapse. They used quantitative, high-speed 3D video microscopy to watch micrometer-sized "buttons" containing oligomerized viral Gag protein form, and then electron microscopy to see that these buttons contained budding viral crescents.
University of Minnesota scientists used a transposon-based genetic screen in mice to identify candidate genes for human colorectal cancers. Crossing mice with mutagenic Sleeping Beauty transposons to mice with SB transposase in gastrointestinal tract epithelium, they were able to analyze more than 16,000 transposon insertions and identify 77 candidate CRC genes. They also identified 17 candidate genes that had not previously been associated with CRC, including POLI, PTPRK, and RSPO2.
And over at Science Insider, the presidential Council on Bioethics fights back with an editorial clarifying its policy in response to President Obama's recent decision to remove restrictions on federal funding of research on embryonic stem cell lines derived in ways that destroy human embryos. They say they never meant to derail any train and in fact, "the aim of this policy was not to shackle scientific research but to find a way to reconcile the need for research with the moral concerns people have." They also say that an emphasis was always put on finding alternate ways to get stem cells, including reprogramming somatic cells to pluripotency.