Imaging and visualization

Guidelines for reporting gene expression localization

Deutsch et al. present guidelines for authors reporting gene expression localization experiments, the minimum information specification for in situ hybridization and immunohistochemistry experiments (MISFISHIE). Six types of information—including experimental design, specimens and treatments, reporters, staining, imaging data, and image characterization—should be provided to allow experiments to be reproduced.

Deutsch, E.W. et al. Nat. Biotechnol. 26, 305–312 (2008).

Gene regulation

Transgene combinatorics

For Caenorhabditis elegans, researchers primarily rely on endogenous enhancers to regulate transgene expression, but this approach restricts them to the spatiotemporal activity of those enhancers during development. Davis et al. created a system to turn on transgene activity when a site-specific recombinase removes an intervening marker gene. Different regulatory regions for the transgene and recombinase create a combinatorial code that can better target transgene expression.

Davis, M.W. et al. PLoS Genet. 4, e1000028 (2008).

Protein biochemistry

Monitoring by SPR transcription

Each step of transcription—from initiation to termination—is dictated by the sequence of the nucleic acids involved and by the proteins comprising the RNA polymerase (RNAP) complex. Greive et al. applied surface plasmon resonance (SPR) technology to quantitate these steps in solution and determine their rate constants. Using this method they observed processes including RNAP binding DNA as well as transcript release and RNAP dissociation at terminators.

Greive, S.J. et al. Proc. Natl. Acad. Sci. USA 105, 3315–3320 (2008).

Microscopy

Pushing the resolution of electron cryomicroscopy

Though electron cryomicroscopy does not usually yield structures with resolution as high as crystallography, no crystallization is needed, and structures can be observed under near-native conditions. Jiang et al. report a 4.5 Å resolution structure for the infectious epsilon15 virus capsid using single-particle electron cryomicroscopy. They obtained this very high resolution for the 22 MDa structure by collecting 20,000 individual particle images and using distributed computing for image processing.

Jiang, W. et al. Nature 451, 1130–1134 (2008).

Microbiology

Complete ORF collection for Vibrio cholerae

Cholera, caused by the bacterium V. cholerae, is still a major public health issue in many parts of the world where it is easily spread through contaminated water. Rolfs et al. report a complete FLEXGene clone set containing full-length open reading frames for a pathogenic V. cholerae strain, with each clone verified by sequencing to ensure high quality. The authors hope that this resource will stimulate research on cholera, and perhaps lead to new vaccines and therapeutic strategies.

Rolfs, A. et al. Proc. Natl. Acad. Sci. USA 105, 4364–4369 (2008).