Discovery opens way to new treatment of metabolic disordersDecember 8th, 2008 - 12:45 pm ICT by IANS
London, Dec 8 (IANS) Researchers have uncovered an important new mechanism with which cells detect nutrients, offering promising new possibilities for treatment of metabolic disorders. About half the drugs are transmitted to cells via receptors, found on exteriors of skin cells (pain and pressure receptors, for example) as well as on the cells of other tissues and organs -the best targets for medicines.
These receptor proteins help cells to communicate with one another and with the outside world. By binding with substances like hormones, receptors that pick up signals from outside the cell, transmit them to cell interiors, setting up all kinds of reactions.
Receptors can be stimulated or blocked to evoke or prevent a certain effect. Foreign substances, such as medicines, can also bind to a receptor and cause a particular effect.
For some time now, scientists have suspected that cells can also detect the presence of food via one or another receptor but no one has known how that happens.
In addition to receptors, cells also have transport proteins that can carry nutrients through the cell membrane to the inside of the cell, where they can be put to use.
Furthermore so-called ‘transceptors’ have been discovered that sense and transport food simultaneously.
Now, Flanders Institute for Biotechnology (VIB) (Belgium) researcher Griet Van Zeebroeck and her colleagues in Johan Thevelein’s group have shown for the first time how one of these transceptors (called Gap1) works.
Gap1 transports amino acids (protein’s building blocks) to the inside of a cell. At the same time, via the same mechanisms that cells use to transmit signals from hormones, Gap1 sends the cell a signal that food is present.
The transceptor apparently uses the same binding site to recognise the food as it uses to grasp the food for transport, according to a VIB release.
This research has been conducted on yeast cells, as yeast (Saccharomyces cerevisiae) is a micro-organism that is used as a model organism. Yeast cells are surprisingly similar to human cells, but they are easier to cultivate and manipulate.