biofilm development.

Nogo receptor antagonists promote axonal regeneration after spinal cord trauma and may improve functional recovery.

Single silvereye colonization events are rarely accompanied by severe founder effects, suggesting new species arise gradually.

channel function.

The variola virus overcomes human viral clearance by inactivation of complement components C3b and C4b.

RAGE (receptor for advanced glycation end-products) and its proinflammatory ligands are commonly identified in the joints of patients with rheumatoid arthritis (RA), but their role in the disease has been unclear. In May Genes and Immunity, Hofmann and colleagues from Columbia University, New York, show that a polymorphism in the RAGE gene within the ligand-binding domain of the receptor (RAGE 82S) may contribute to enhanced proinflammatory mechanisms in immune/inflammatory diseases (Genes Immun

A novel population of muscle stem cells from mice could hold the key to the treatment of muscle-wasting diseases.

A short daytime nap may contribute to the consolidation of learning and improve performance in visual discrimination tasks.

Most of the physiological and behavioral processes in mammals exhibit a daily rhythm, maintained by a central 'clock' in the brain, but the molecules that connect the brain clock with the body remain unknown. In 23 May Nature, Michelle Cheng and colleagues from University of California, Irvine, show that prokineticin 2, a cysteine-rich secreted protein, functions as an output molecule from the suprachiasmatic nucleus to the rest of the body.Cheng et al. studied mice under dark and light conditio

Considerable debate still exists bout the precise nature of the mechanisms involved in the process of natural selection. In 23 May Nature, Patrik Nosil and colleagues from Simon Fraser University, Burnaby, Canada, show that divergent selection for host adaptation, and not genetic drift, has promoted the parallel evolution of sexual isolation in the walking-stick insect Timema cristinae (Nature 2002, 417:440-443).Nosil et al. studied populations of T. cristinae from eight study sites in the Santa

Direct activation of mast cells via Toll-like receptors 2 or 4 by respective microligands contributes to innate and allergic immune responses.

Antibody responses by B cells become more specific over time in a process known as 'affinity maturation', but the role of antibody affinity for antigens in controlling B lymphocyte selection remains unclear. In 20 May Nature Immunology, Tien-An Yang Shih and colleagues from Rockefeller University, New York, show that strict selection for high-affinity B cell clones is imposed at an early stage of the T cell-dependent immune response in vivo (Nat Immunol 2002, DOI: 10.1038/ni803).Shih et al. comp