all Michael Levin stories

Brain chemical serotonin involved in early embryo patterning

70652986 — Mon, 26 Mar 2007 06:18:11 -0400

A study published in the May 10, 2005, Current Biology has ramifications for neuroscience, developmental genetics, evolutionary biology and, possibly, human teratology (a branch of pathology and embryology concerned with abnormal development and congenital malformations). Among other results, the study, which was carried on frog and chick embryos: • Provides the first molecular support for the idea that serotonin is utilized as a large-scale left-right patterning mechanism, thus offering new insight into the basis of position of the heart and other asymmetric, visceral organs. • Identifies a possible novel serotonin signaling pathway, providing evidence that serotonin can signal inside the cell. If also found in mammals, such signaling, which may be important in brain functioning, would suggest numerous new roles and possible targets for serotonin-related drugs like the selective serotonin reuptake inhibitors (SSRI antidepressants such as Prozac and Zoloft) or the monoamine oxidase inhibitors (MAOIs). • Could lead to a greater understanding of potential health risks from drug families that target the serotonin pathway in human patients. • Sheds light on the evolutionary origin of a crucial neurological control system, suggesting that neuronal synapses using serotonin as a neurotransmitter may have arisen through the adaptation of ancient, fundamental cell-cell signals to a new purpose as nervous systems evolved. The team was led by principal investigator Michael Levin, assistant professor at Harvard Medical School. The study was funded by the National Science Foundation and the American Heart Association.

Is your heart in the right place?

70652986 — Mon, 26 Mar 2007 05:32:57 -0400

In a frog, the position of the heart is determined within the first hour in the womb, Harvard scientists have discovered. Researchers all over the world believe that frogs and humans develop in a similar way. Experiments show, for example, that some of the same mechanisms put the hearts of both creatures on the left side. The proteins responsible for shifting around a frog embryo's heart, gut, gall bladder, and other organs are also found in abundance in human embryos. "Our research shows the same protein family, known as 14-3-3, plays important roles across the three kingdoms of living things, fungi, plants, and animals," says Michael Levin, a biologist at the Harvard School of Dental Medicine and the Forsyth Institute in Boston. "Our latest findings provide strong evidence that the determination of right-left asymmetry in vertebrates, possibly including humans, occurs at a much earlier time than previously believed." Levin and two colleagues from the Netherlands described their newest experiments in the Oct. 20, 2003 issue of the journal Development.

How your heart got where it is

70652986 — Mon, 26 Mar 2007 05:24:06 -0400

A team of scientists at the Harvard School of Dental Medicine and The Forsyth Institute in Boston believes it has found the answer to how bodily organs are formed. And it's electrifying. "All living things generate all sorts of electric fields inside themselves," explains Michael Levin, an assistant professor at the Dental School and a researcher at The Forsyth Institute. "That's part of life. We have discovered a whole new role for these fields, not expected or explored before. We've found that they control the geometric arrangement, the shape, of visceral organs such as the heart, stomach, liver, spleen, and probably the brain." The researchers have also identified the genes that hold the blueprints of this organ geometry.