Hugh Pickens writes: "The Telegraph reports that 4,000 microscopic worms were onboard Space Shuttle Atlantis when it launched today. Their mission — to help experts in human physiology understand more about what triggers the body to build and lose muscle. The worms are bound for the Japanese Experiment Module ''Kibo'' on the International Space Station (ISS) where they will experience the same weightless conditions which can cause dramatic muscle loss, one of the major health concerns for astronauts. ''If we can identify what causes the body to react in certain ways in space we establish new pathways for research back on earth," says Dr Nathaniel Szewczyk. The worms, Caenorhabditis elegans, have been carefully selected and brought to a dormant state for the journey, traveling in special cell culture bags. Once in space they will be brought back from their dormant state with the release of food, exposed to conditions in space for four days and then frozen in preparation for the return journey. The effect of this journey on their muscle mass will be investigated once the worms are returned to earth. "Some of our worms will be treated with RNAi against specific proteases to see if we can stop muscle protein degradation in space," adds Szewczyk. ''The CERISE payload is an important space medicine experiment as it will establish if RNAi, which was the subject of the 2006 Nobel Prize in Medicine, is a viable technique for altering the biological response to space flight."