The action of neurotrophins, factors that modulate the differentiation, maturation and neuronal regeneration, and even death of neurons, is carried out through specific receptors. Among them, the Trk A tyrosine kinase with activity. After activation, these receptors give rise to an intracellular signaling cascade, which culminates with the expression of certain genes.

So far, these receptors were found only in vertebrates, and the search had been barren of invertebrates, made in the two most widely used models, Drosophila melanogaster and Caenorhabditis elegans, as their appearance was related to the evolution of early vertebrates. However, a paper published in Development, in collaboration between the universities of Barcelona and Lleida, has identified the Trk

A team of researchers from the Autonomous University of Barcelona published a study showing that transposons can silence genes adjacent to or significantly reduce its expression by induction of synthesis of an antisense RNA. This new mechanism is now described, unknown until now, has been observed in the genome of Drosophila buzzatii. In the human genome sequences corresponding to transposons may account for up to 45% of genetic material.

The work discussed is the extension of some previous studies by this group of the Department of Genetics and Microbiology at the UAB, which earned them a 1999 article in Science, which showed that the activity of the transposon generated a chromosomal inversion in D. Buzzatii,