Volume 8 Issue 10, October 2011

Two-gram microscopes make brain images in moving mice.

In vitro reconstitution of mouse germ cell development makes it possible to convert mouse pluripotent stem cells into primordial germ cells, which go on to generate functional sperm in vivo.

Researchers describe a GFP mimic for fluorescently labeling RNA molecules.

A gene-counting method can be used to profile gene expression differences in an organism that lacks a sequenced genome.

A fluorescence-compatible tissue-clearing reagent enables light microscopy–based imaging deep in the mouse brain.

Using a sheet of light to perform fluorescence-correlation analysis, scientists can track protein dynamics in entire cellular 'neighborhoods'.

Engineering the genetic code of bacteria and worms opens up new possibilities.

The toughest work is not sequencing a genome: it is finding the mutations that matter.

Induced pluripotent stem cells have been derived from two endangered wildlife species. There are exciting possibilities, yet formidable challenges, for these cells to contribute to real-life species preservation.

A comparison of embryonic stem cells and induced pluripotent stem cells on the proteome level reveals subtle distinctions between these cell types that might explain differences in their ability to differentiate into specific lineages.

The combination of optogenetics with feedback control counteracts variability in cellular signaling responses to promote a deeper understanding of the biochemical mechanisms involved.

Presented is a Review of the principles and practice of optical sectioning microscopy using planar illumination or structured illumination with descriptions of the advantages and disadvantages of these techniques.

A comparison of the proteomes and phosphoproteomes of four human embryonic stem cell lines and four induced pluripotent stem cell lines is reported, revealing subtle differences in these cell types at the protein level. Also introduced is the Stem Cell-Omics Repository (SCOR), a database of quantitative information for transcripts, proteins and post-translational modifications.

Reprogramming to induced pluripotency of cells from the endangered silver-maned drill and the northern white rhinoceros is reported. Induced pluripotent stem cells from endangered species may prove useful for species preservation in the future.

An algorithm for linear mixed models substantially reduces memory usage and run time for genome-wide association studies. The improved algorithm scales linearly in cohort size, allowing the application of these models to much larger samples.

Feedback control of a light-gated protein-protein interaction is used to deliver precisely tuned intracellular signals to cultured cells.

Expression profiles of several hundred microRNAs in the blood of individuals with disease, including autoimmune disease, cancers, cardiovascular disease and chronic inflammatory disease are reported.

A method for performing quantitative proteomics experiments in Caenorhabditis elegans using stable-isotope labeling of lysine is described. The method can be coupled with RNA interference to examine global effects on the proteome. Also in this issue, Larance et al. describe a very similar method.

A method for performing quantitative proteomics experiments in Caenorhabditis elegans using stable-isotope labeling with amino acids in cell culture (SILAC) is described. The authors used the method to identify heat shock–responsive proteins in worms. Also in this issue, Fredens et al. describe a very similar method.

This paper reports transgenesis by genetic modification of gametes in the domestic cat. The approach is used to generate transgenic cats expressing a virus restriction factor from rhesus macaque.

Presented is an experimental analysis of the stability of transgene expression, the perturbation of endogenous expression and the perturbation of epigenetic organization upon site-directed delivery of transgenes to the CCR5 and AAVS1 loci in human cells. It provides guidelines for optimal cassette design for stable and nonperturbative gene transfer.

An integrated, miniature (1.9 g) fluorescence microscope containing light source, optics and sensor allows high-speed, wide field of view imaging of calcium spiking in hundreds of neurons in freely moving mice. The mass-producible portable microscope is also useful for a variety of fluorescence assays for which size, cost and portability can be concerns.

Destabilized mutants of firefly luciferase are characterized as sensors for protein homeostasis (proteostasis). Their use as tools for comparisons of proteostasis capacity is demonstrated in cells and in Caenorhabditis elegans.