Depending on the environment in which the worm grows, the larva of the roundworm Pristionchus pacificus develops into either a wide-mouthed predator or a narrow-mouthed bacteria eater. A team of researchers at the Max Planck Institute for Evolutionary Biology in Tbingen, Germany, headed by Ralf J. Sommer have now discovered a developmental biological switch that determines the worm's mouth form. According to this, the scientists are now able to explain how organisms adapt to different surrounding conditions.
When it comes to survival, flexibility is a trump card. This principle also applies to the microscopic roundworm Pristionchus pacificus, which is being researched by scientists at the Max Planck Institute for Developmental Biology in a study headed by Ralf Sommer. Depending on the environment in which Pristionchus grows, it develops either a short wide mouth or a long narrow one. The wide-mouthed variant, which has a single, characteristic tooth, is suitable for carrying out predatory attacks. The narrow version, in contrast, is mainly used for grazing on bacterial food sources. The developmental path taken by a Pristionchus larva is not decided by its genes but by the environment. When the animals were starved or when too many worms crowded the Petri dish, the researchers observed the increased development of the wide-mouthed variant.
Erik Ragsdale, Manuela Mller, Christian Rdelsperger and Ralf Sommer have now discovered a crucial interface between the worm's environment and its developmental genes. The Tbingen-based scientists found a gene which functions like a switch and selects the suitable variant from the two possible mouth forms.
The discovery of this gene was the crowning success of a genetic experiment, to which roundworms are particularly suited due to their short generation time. Ragsdale and Mller discovered mutated worm lines which only produce worms with narrow mouths, irre
|Contact: Erik Ragsdale|