Cell biology of the neuron

Trafficking of prion proteins through a caveolae-mediated endosomal pathway. Peters, P. J. et al. J. Cell Biol. 162, 703–717 (2003)

Peters et al. used immunoelectron microscopy to analyse the trafficking of the prion protein PrPC in CHO cells, and found that it uses an atypical endocytic pathway to reach the lysosomes. This pathway does not involve clathrin-coated vesicles, but contains caveolin-1, a protein that is characteristic of caveolae. The data raise the possibility that transit through this unusual pathway might be involved in the conversion of PrPC to the pathogenic form PrPSc.

Cognitive neuroscience

Features of neuronal synchrony in mouse visual cortex. Nase, G. et al. J. Neurophysiol. 90, 1115–1123 (2003)

Gamma oscillations and their relevance to feature binding have been largely studied in primates and in vitro. Here, the authors investigated whether the mouse would be a suitable model for the study of gamma oscillations, and found that different stimuli elicited oscillations and neuronal synchronization that were similar to what has been found in other models. These results open up the possibility of bringing the strengths of the mouse as a genetic model to bear on the problem of perceptual binding.

Neurophysiology

Sensitivity of neurons to weak electric fields. Francis, J. T. et al. J. Neurosci. 23, 7255–7261 (2003)

Weak electric fields can modulate neuronal activity, but the sensitivity threshold of neurons has not been clearly defined. Here, the authors measured the sensitivity of hippocampal networks to weak fields and found, first, that networks are more sensitive than single neurons and, second, that the sensitivity threshold is one order of magnitude below what was previously thought. As weak electric fields are a common environmental feature, these results might have implications for the assessment of their effect on public health.

Neurodegenerative diseases

Isolation of drugs active against mammalian prions using a yeast-based screening assay. Bach, S. et al. Nature Biotechnol. 21, 1075–1081 (2003)

Yeast prions cause specific phenotypes in this organism, and Bach et al. took advantage of them to develop a two-step, high-throughput assay to screen for drugs that interfere with prion action. They found that two previously known anti-prion agents were effective in their assay, and identified a new class of compounds — the kastellpaolitines — as similarly effective drugs. The authors found that these molecules also acted against mammalian prions, indicating that the pathways that control prion accumulation might be conserved between yeast and mammals.