Sperm go slow without a crucial protein.

The discovery of a protein that is crucial to sperm swimming in mice could lead to new male or female contraceptives or fertility treatments.

The protein forms a channel through the membrane of the sperm tail. It controls the inflow of calcium ions that trigger swimming.

All humans have the gene that encodes the channel, but it is switched on only in sperm cells. This would lessen the risk of side-effects from any channel-blo

Chemists copy bacterial tricks for making clean fuel.

Bacteria are teaching chemists their tips for creating lean, green fuel. US researchers have developed a catalyst based on a bacterial enzyme that converts cheap acids to hydrogen, the ultimate clean power source.

Unlike other fuels, hydrogen is non-polluting: its combustion makes only water, instead of greenhouse gas carbon dioxide or the poison carbon monoxide. Thomas Rauchfuss and colleagues at the University of Illino

Cosmic lens magnifies faint galactic building-block.

Astronomers have peered deep into space and time and spotted a baby galaxy. Their results suggest that the tiny star-forming region may have helped to build today’s Universe 1 .

“We believe this is one of the galactic building-blocks that join together to make larger galaxies,” says Konrad Kuijken, of the Kapteyn Institute in Groningen, the Netherlands, a member of the team that found the object. The mergin

Sequencers expose secret chromosome centre.

February’s celebrations hid a dark secret: the human genome sequencers hadn’t touched the hearts of our chromosomes. Now, at last, one chromosome’s inscrutable midpoint, its centromere, has given up its genetic secrets.

Centromeres look like the ’waist’ in an X. They share out chromosomes fairly when a cell divides. Defective centromeres may underlie many cancers, in which problems with chromosome movement

Stripes help chemists shop for molecules.

Scientists may soon be sticking bar-coded metal rods into molecules to see what they do in a crowd 1 . The rods could help to track the functions and interactions of genes, and may aid drug discovery.

At only a few thousandths of a millimetre long, the rods are small enough to fit inside a single red blood cell. Christine Keating, of Pennsylvania State University, and colleagues cast them inside cylindrical pores in a

A new way to find genes and map disease.

A new technique should aid the hunt for genes in the human genome sequence. The method, which tracks only switched-on genes in cells, will help researchers to distinguish between diseased and normal tissues, and could point the way to new treatments.

Andrew Simpson, of the Ludwig Institute for Cancer Research in Sao Paulo, Brazil, and colleagues have produced a whopping 700,000 DNA tags, representing the genes that are active in 24 no