OBITUARY:Roy Cuthbertson

Fertilisation of the egg is said to be the only aspect of cell biology familiar to the lay person. But how, precisely, does a sperm switch on the egg, a thousand-fold bigger, to start the cell divisions that result in formation of the early embryo? Roy Cuthbertson showed in 1985 that the sperm induces the egg to generate a series of brief rises in the calcium level in the egg; these calcium "spikes" are a mandatory signal for egg development.

Just two weeks ago, a few days after Cuthbertson's death, a London group reported in the scientific journal Nature that they had identified a protein which is injected into the egg by the sperm and which is responsible, somehow, for initiating the calcium spiking. Cuthbertson's 1985 discovery, also published in Nature, was fundamental to the identification of the sperm protein.

Roy Cuthbertson was born in 1954 and educated at Tonbridge and King's College, Cambridge, where he read Mathematics; he then took an MSc in Genetics at University College London. He began his research career with D.G. Whittingham in the Mammalian Development Unit at UCL.

He gained his doctorate in 1981 and after a year at Harvard came to Liverpool University determined to take on the technical challenge of measuring the egg's calcium levels during fertilisation. He used an extract from a luminous jellyfish that glowed when given calcium. By injecting this extract into an egg and measuring the glow from the egg with light-detecting instruments he showed that a fertilised egg generates about 12 brief spikes in its calcium level over the three-hour period after the sperm binds. A year later, with Niall Woods and myself, he used the same technique to show, much to everyone's surprise (except his own), that a liver cell responds to several hormones by generating calcium spikes. In these cells the calcium spiking switches on the release of glucose into the bloodstream, not cell division.

This work, again published in Nature, firmly established his reputation in cell signalling internationally and he was awarded a Royal Society 1983 University Research Fellowship.

Cuthbertson had the intellect, confidence and determination to forge his own path in science; not for him the easy next step, or following the latest fashionable topic. All he lacked was time, as the leukaemia which he had battled against for several years overwhelmed him.

Roy Cuthbertson was a cellist with the Chester Philharmonic Orchestra, and an active campaigner for the Green Party. His concern for the planet's problems befits a scientist who contributed much to our understanding of the cellular events that initiate human procreation.

Peter Cobbold

Kevin Siward Roy Cuthbertson, cell biologist and mathematician: born Sevenoaks 2 May 1954; Royal Society 1983 University Research Fellow, Liverpool University 1987-96; married Anne Tebbs (one son, one daughter); died Liverpool 11 January 1996.