New Worlds: Aging and the worm

Studies on the tiny C. elegans worm comprise a step towards understanding cell mutations that cause a variety of human diseases.

By JUDY SIEGEL-ITZKOVICH
Studies on the tiny C. elegans worm comprise a step towards understanding cell mutations that cause a variety of human diseases, particularly in children including that which brings about premature aging and early death. The research was conducted by researchers at the Hebrew University of Jerusalem's Silberman Institute of Life Sciences and the John Hopkins University School of Medicine. They focused on induced mutations in the nuclear envelope of cells from the much-studied worm, with the aim of providing clues to a better understanding of mutations in proteins of the cell nucleus envelope in humans. Such mutations, particularly in lamin (nuclear envelope) proteins A and C, cause many different diseases, including Hutchison Gilford progeria syndrome. Young victims of this disease develop premature aging and die usually before the age of 13. Other diseases brought about by these mutations include a form of muscular dystrophy, cardiomyopathy (a weakening of the heart muscle) and various other forms of irregular or retarded growth in childhood. A report on the lamin research project was published in a recent issue of the Proceedings of the [US] National Academy of Sciences and carried out primarily by Ayelet Margalit, a HU doctoral student in genetics, working under the supervision of Prof. Yosef Gruenbaum, and in cooperation with Prof. Katherine Wilson and Dr. Miriam Segura-Totten of Johns Hopkins. Experimenting with removal of the worm's lamin protein or its interacting protein partners emerin, MAN1 or BAF, the researchers have described "down-the-line" consequences, including the disruption of various proteins necessary for normal cell reproduction. Even though the C. elegans worm has only one lamin protein and few proteins that interact with it, the processes that occur there are similar to what happens in humans and provide clues to the laminopathic diseases affecting people. The results seen from these disruptions are a halted process of cell division, resulting in a static "bridge" structure between cells that should have separated, plus damage to the gonad cell structure. In both cases, the ability of the organism to grow and to reproduce is severely impaired. The researchers hope that through further laboratory experimentation with the worm they will be able to better understand the functions of lamin-based complexes and why mutations in these proteins cause a variety of laminopathic diseases, such as progeria and muscular dystrophy in humans. DOGGED COACH KEEPS DIETERS ON LEASH A robot dog that monitors one's daily food intake and exercise levels and warns you not to eat that cheesecake could encourage people to stick to their diets. The health-conscious pooch connects wirelessly to the dieter's pedometer and an electronic diary of his eating habits, to calculate his daily calorie intake and expenditure. While it may sound frivolous, its US developers hope the robot, a souped-up version of Sony's dog Aibo, could ultimately help in the fight against the Western world's obesity epidemic. The system is being designed by Cynthia Breazeal at the MIT Media Lab in Cambridge, Massachusetts, who is famed for creating the emotional robot Kismet. It would use a pedometer, bathroom scales and a PDA connected by Bluetooth or Wi-Fi to gather information about weight, activity and eating habits that people generally have trouble calculating, remembering and reporting. A computer will then accurately analyze the data and present the results to the person through the friendly face of a robot, says Breazeal's student Cory Kidd, who is working with her to develop the system, which is still at an early stage. Kidd presented the idea at the recent UbiComp conference in Tokyo and will begin a study on 30 overweight Bostonians next spring. Past studies have shown that people who accurately record what they eat and how much they exercise are more likely to keep their weight down, and that a real 3-D robot is more convincing than an on-screen character. A robot could also offer support that humans don't have the time, patience or desire to provide. Aibo does not talk. Instead he has been programmed to exhibit four different behaviors, representing lethargy, energy and two stages in between, in response to a verbal cue such as "How am I?" Aibo will choose his response to mirror how the person should be feeling. If you have stuck to your daily calories, he will jump up and down, wag his tail, play vibrant music and flash the brightly colored LEDs that pepper his 50-centimeter-tall plastic body. But if you have already had too many, he will move slowly and lethargically and play low-energy music. "It's promising to look at mobile robots for defining behavioral change," says Tim Bickmore, a computer scientist at the Boston University School of Medicine, who showed recently that an animated computer companion could encourage people to exercise more.